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Sample records for improved pharmaceutical properties

  1. Eutectics as improved pharmaceutical materials: design, properties and characterization.

    PubMed

    Cherukuvada, Suryanarayan; Nangia, Ashwini

    2014-01-28

    Eutectics are a long known class of multi-component solids with important and useful applications in daily life. In comparison to other multi-component crystalline solids, such as salts, solid solutions, molecular complexes and cocrystals, eutectics are less studied in terms of molecular structure organization and bonding interactions. Classically, a eutectic is defined based on its low melting point compared to the individual components. In this article, we attempt to define eutectics not just based on thermal methods but from a structural organization view point, and discuss their microstructures and properties as organic materials vis-a-vis solid solutions and cocrystals. The X-ray crystal structure of a cocrystal is different from that of the individual components whereas the unit cell of a solid solution is similar to that of one of the components. Eutectics are closer to the latter species in that their crystalline arrangement is similar to the parent components but they are different with respect to the structural integrity. A solid solution possesses structural homogeneity throughout the structure (single phase) but a eutectic is a heterogeneous ensemble of individual components whose crystal structures are like discontinuous solid solutions (phase separated). Thus, a eutectic may be better defined as a conglomerate of solid solutions. A structural analysis of cocrystals, solid solutions and eutectics has led to an understanding that materials with strong adhesive (hetero) interactions between the unlike components will lead to cocrystals whereas those having stronger cohesive (homo/self) interactions will more often give rise to solid solutions (for similar structures of components) and eutectics (for different structures of components). We demonstrate that the same crystal engineering principles which have been profitably utilized for cocrystal design in the past decade can now be applied to make eutectics as novel composite materials, illustrated by

  2. Exploration of crystal simulation potential by fluconazole isomorphism and its application in improvement of pharmaceutical properties

    NASA Astrophysics Data System (ADS)

    Thakur, Amitha; Kumar, Dinesh; Thipparaboina, Rajesh; Shastri, Nalini R.

    2014-11-01

    Control of crystal morphology during crystallization is a paramount challenge in pharmaceutical processing. Hence, there is need to introduce computational methods for morphology prediction to manage production cost of drugs and improve related pharmaceutical and biopharmaceutical properties. Layer docking approach with molecular dynamics opens a new avenue for crystal habit prediction in presence of solvent. In the present study, attempts were made to correlate predicted and experimental crystal habits of fluconazole considering solvent interactions using layer docking approach. Simulated results from layer docking approach with methanol as solvent gave two dominant facets (0 1 1) and (1 0 1) with a surface area 22.43% and 19.82% respectively, which were in agreement with the experimental results. Experimentally grown modified crystal habit of fluconazole in methanol showed enhanced dissolution rate (p<0.05) when compared to plain drug. This was attributed to the increased surface area on the specified facets caused by interactions with the solvent. Furthermore, Differential Scanning Calorimetry, Fourier Transform Infrared (FTIR) Spectroscopy and powder X-ray Diffraction of recrystallized samples confirmed only a habit change and absence of any polymorphs, hydrates or solvates. Flow and compressibility of fluconazole recrystallized in methanol was significantly improved when compared to plain drug. This study demonstrates a methodical approach using computational tools for prediction and modification of crystal habit, to enhance dissolution of poorly soluble drugs, for future pharmaceutical applications.

  3. Improved blend and tablet properties of fine pharmaceutical powders via dry particle coating.

    PubMed

    Huang, Zhonghui; Scicolone, James V; Han, Xi; Davé, Rajesh N

    2015-01-30

    The improvements in the flow and packing of fine pharmaceutical powder blends due to dry coating of micronized acetaminophen (mAPAP, ∼11μm), a model poorly flowing drug, are quantified. Poor flow and packing density of fine excipients (∼20μm) allowed testing the hypothesis that dry coating of cohesive API may counteract poor flow and packing of fine pharmaceutical powder blends. Further, fine excipients could improve compaction and reduce segregation tendency. It was found that flow function coefficient (FFC) and bulk density enhancements for 10%, 30%, and 60% (w/w), API loading blends with dry coated API are significantly higher than those without coated silica. At the highest API loading, for which coarser excipients were also used as reference, the flow and packing of dry coated mAPAP blends were significantly increased regardless of the excipient particle size, exceeding those of a well compacting excipient, Avicel 102. In addition, tensile strength of tablets with fine excipients was significantly higher, indicating improved compactibility. These results show for the first time that dry coating of fine, cohesive API powder leads to significantly improved flow and packing of high API loading blends consisting of fine excipients, while achieving improved tablet compactibility, suggesting suitability for direct compaction.

  4. Pharmaceutical Cocrystals and Their Physicochemical Properties

    PubMed Central

    2009-01-01

    Over the last 20 years, the number of publications outlining the advances in design strategies, growing techniques, and characterization of cocrystals has continued to increase significantly within the crystal engineering field. However, only within the last decade have cocrystals found their place in pharmaceuticals, primarily due to their ability to alter physicochemical properties without compromising the structural integrity of the active pharmaceutical ingredient (API) and thus, possibly, the bioactivity. This review article will highlight and discuss the advances made over the last 10 years pertaining to physical and chemical property improvements through pharmaceutical cocrystalline materials and, hopefully, draw closer the fields of crystal engineering and pharmaceutical sciences. PMID:19503732

  5. Characterization of the surface properties of a model pharmaceutical fine powder modified with a pharmaceutical lubricant to improve flow via a mechanical dry coating approach.

    PubMed

    Zhou, Qi Tony; Denman, John A; Gengenbach, Thomas; Das, Shyamal; Qu, Li; Zhang, Hailong; Larson, Ian; Stewart, Peter J; Morton, David A V

    2011-08-01

    The aim of this study is to investigate the changes in physical and chemical surface properties of a fine lactose powder, which has been processed by a mechanical dry coating approach. A commercially available milled lactose monohydrate powder (median diameter around 20 μm) was dry coated with a pharmaceutical lubricant, magnesium stearate (MgSt). Substantial changes in bulk behavior have been shown previously and the purpose of the current work was to understand the relationship between these bulk changes and physico-chemical changes in the surface. X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry results demonstrated both qualitatively and quantitatively how the chemical properties of the lactose particle surfaces had been altered. The characterization results indicated that a high-level coverage of a thin coating layer of MgSt has been created through the coating. Inverse gas chromatography was used to probe the surface energetic changes, and at conditions of finite dilution, provided a new insight into surface energy changes. This work demonstrated that the modifications of the surface physical and chemical properties correlated with the reduction in powder cohesion and improvement in powder flow.

  6. Thermal properties of food and pharmaceutical powders

    NASA Astrophysics Data System (ADS)

    Abiad, Mohamad Ghassan

    Foods and pharmaceuticals are complex systems usually exposed to various environmental conditions during processing and thus storage, stability, functionality and quality are key attributes that deserve careful attention. The quality and stability of foods and pharmaceuticals are mainly affected by environmental conditions such as temperature, humidity, time, and processing conditions (e.g. shear, pressure) under which they may undergo physical and/or chemical transformations. Glass transition as well as other thermal properties is a key to understand how external conditions affect physical changes of such materials. Development of new materials and understanding the physico-chemical behavior of existing ones require a scientific foundation that translates into safe and high quality foods, improved quality of pharmaceuticals and nutraceuticals with lower risk to patients and functional efficacy of polymers used in food and medicinal products. This research provides an overview of the glass transition and other thermal properties and introduces novel methods developed to characterize such properties.

  7. Improving environmental risk assessment of human pharmaceuticals.

    PubMed

    Ågerstrand, Marlene; Berg, Cecilia; Björlenius, Berndt; Breitholtz, Magnus; Brunström, Björn; Fick, Jerker; Gunnarsson, Lina; Larsson, D G Joakim; Sumpter, John P; Tysklind, Mats; Rudén, Christina

    2015-05-01

    This paper presents 10 recommendations for improving the European Medicines Agency's guidance for environmental risk assessment of human pharmaceutical products. The recommendations are based on up-to-date, available science in combination with experiences from other chemical frameworks such as the REACH-legislation for industrial chemicals. The recommendations concern: expanding the scope of the current guideline; requirements to assess the risk for development of antibiotic resistance; jointly performed assessments; refinement of the test proposal; mixture toxicity assessments on active pharmaceutical ingredients with similar modes of action; use of all available ecotoxicity studies; mandatory reviews; increased transparency; inclusion of emission data from production; and a risk management option. We believe that implementation of our recommendations would strengthen the protection of the environment and be beneficial to society. Legislation and guidance documents need to be updated at regular intervals in order to incorporate new knowledge from the scientific community. This is particularly important for regulatory documents concerning pharmaceuticals in the environment since this is a research field that has been growing substantially in the last decades.

  8. Purified guar galactomannan as an improved pharmaceutical excipient.

    PubMed

    Gebert, M S; Friend, D R

    1998-08-01

    The purpose of this study was to assess certain pharmaceutical attributes of guar galactomannan, a hydrocolloid polysaccharide obtained from the endosperm of the leguminous plant Cyamopsis tetragonolobus (L.), following purification using both literature procedures and new processes. Experiments were performed to measure viscosity, hydration rate, tablet hardness, and dissolution profiles of guar galactomannan both before and after purification. The viscosity of an aqueous 1% purified galactomannan solution is typically 40-50% higher than its unpurified guar galactomannan precursor. The hydration rate of an aqueous 1% purified galactomannan solution increases by 100% after purification. These physicochemical changes resulted in improvements in pharmaceutical properties such as better stir speed independence in both tablet and capsule dissolution profiles and improved tablet hardness. For instance, time to 50% dissolution of ranitidine HCl from capsules containing unpurified guar gum was 0.4 and 1.8 hr at 20 and 40 rpm, respectively, using USP Apparatus II. Using the same amount of purified guar gum and the same conditions (20 and 40 rpm), these values were increased to 2.9 and 3.8 hr, respectively. These data demonstrate a reduced effect of changing agitation conditions and the need for less guar gum to sustain the release of a water-soluble drug. Tablet hardness of purified guar gum (particle size < 75 microns) was about 7 kP and the same unpurified guar gum of equal particle size and hydration gave a hardness of less than 1 kP. PMID:9742552

  9. Pharmaceutical and Toxicological Properties of Engineered Nanomaterials for Drug Delivery

    PubMed Central

    Palombo, Matthew; Deshmukh, Manjeet; Myers, Daniel; Gao, Jieming; Szekely, Zoltan; Sinko, Patrick J.

    2014-01-01

    Novel engineered nanomaterials (ENMs) are being developed to enhance therapy. The physicochemical properties of ENMs can be manipulated to control/direct biodistribution and target delivery, but these alterations also have implications for toxicity. It is well known that size plays a significant role in determining ENM effects since simply nanosizing a safe bulk material can render it toxic. However, charge, shape, rigidity, and surface modifications also have a significant influence on the biodistribution and toxicity of nanoscale drug delivery systems (NDDSs). In this review, NDDSs are considered in terms of platform technologies, materials, and physical properties that impart their pharmaceutical and toxicological effects. Moving forward, the development of safe and effective nanomedicines requires standardized protocols for determining the physical characteristics of ENMs as well as assessing their potential long-term toxicity. When such protocols are established, the remarkable promise of nanomedicine to improve the diagnosis and treatment of human disease can be fulfilled. PMID:24160695

  10. Does Intellectual Property Restrict Output? An Analysis of Pharmaceutical Markets.

    PubMed

    Lakdawalla, Darius; Philipson, Tomas

    2012-02-01

    Standard normative analysis of intellectual property focuses on the balance between incentives for research and the static welfare costs of reduced price-competition from monopoly. However, static welfare loss from patents is not universal. While patents restrict price competition, they may also provide static welfare benefits by improving incentives for marketing, which is a form of non-price competition. We show theoretically how stronger marketing incentives mitigate, and can even offset, the static costs of monopoly pricing. Empirical analysis in the pharmaceutical industry context suggests that, in the short-run, patent expirations reduce consumer welfare as a result of decreased marketing effort. In the long-run, patent expirations do benefit consumers, but by 30% less than would be implied by the reduction in price alone. The social value of monopoly marketing to consumers alone is roughly on par with its costs to firms. PMID:25221349

  11. Does Intellectual Property Restrict Output? An Analysis of Pharmaceutical Markets*

    PubMed Central

    Lakdawalla, Darius; Philipson, Tomas

    2013-01-01

    Standard normative analysis of intellectual property focuses on the balance between incentives for research and the static welfare costs of reduced price-competition from monopoly. However, static welfare loss from patents is not universal. While patents restrict price competition, they may also provide static welfare benefits by improving incentives for marketing, which is a form of non-price competition. We show theoretically how stronger marketing incentives mitigate, and can even offset, the static costs of monopoly pricing. Empirical analysis in the pharmaceutical industry context suggests that, in the short-run, patent expirations reduce consumer welfare as a result of decreased marketing effort. In the long-run, patent expirations do benefit consumers, but by 30% less than would be implied by the reduction in price alone. The social value of monopoly marketing to consumers alone is roughly on par with its costs to firms. PMID:25221349

  12. Design, synthesis, and analysis of a polyethelene glycol-modified (PEGylated) small molecule inhibitor of integrin {alpha}4{beta}1 with improved pharmaceutical properties.

    PubMed

    Pepinsky, R B; Lee, W-C; Cornebise, M; Gill, A; Wortham, K; Chen, L L; Leone, D R; Giza, K; Dolinski, B M; Perper, S; Nickerson-Nutter, C; Lepage, D; Chakraborty, A; Whalley, E T; Petter, R C; Adams, S P; Lobb, R R; Scott, D M

    2005-02-01

    Integrin alpha4beta1 plays an important role in inflammatory processes by regulating the migration of leukocytes into inflamed tissues. Previously, we identified BIO5192 [2(S)-{[1-(3,5-dichloro-benzenesulfonyl)-pyrrolidine-2(S)-carbonyl]-amino}-4-[4-methyl-2(S)-(methyl-{2-[4-(3-o-tolyl-ureido)-phenyl]-acetyl}-amino)-pentanoylamino]-butyric acid], a highly selective and potent (K(D) of 9 pM) small molecule inhibitor of alpha4beta1. Although BIO5192 is efficacious in various animal models of inflammatory disease, high doses and daily treatment of the compound are needed to achieve a therapeutic effect because of its relatively short serum half-life. To address this issue, polyethylene glycol modification (PEGylation) was used as an approach to improve systemic exposure. BIO5192 was PEGylated by a targeted approach in which derivatizable amino groups were incorporated into the molecule. Two sites were identified that could be modified, and from these, five PEGylated compounds were synthesized and characterized. One compound, 2a-PEG (K(D) of 19 pM), was selected for in vivo studies. The pharmacokinetic and pharmacodynamic properties of 2a-PEG were dramatically improved relative to the unmodified compound. The PEGylated compound was efficacious in a rat model of experimental autoimmune encephalomyelitis at a 30-fold lower molar dose than the parent compound and required only a once-a-week dosing regimen compared with a daily treatment for BIO5192. Compound 2a-PEG was highly selective for alpha4beta1. These studies demonstrate the feasibility of PEGylation of alpha4beta1-targeted small molecules with retention of activity in vitro and in vivo. 2a-PEG, and related compounds, will be valuable reagents for assessing alpha4beta1 biology and may provide a new therapeutic approach to treatment of human inflammatory diseases.

  13. Improving Pharmaceutical Protein Production in Oryza sativa

    PubMed Central

    Kuo, Yu-Chieh; Tan, Chia-Chun; Ku, Jung-Ting; Hsu, Wei-Cho; Su, Sung-Chieh; Lu, Chung-An; Huang, Li-Fen

    2013-01-01

    Application of plant expression systems in the production of recombinant proteins has several advantages, such as low maintenance cost, absence of human pathogens, and possession of complex post-translational glycosylation capabilities. Plants have been successfully used to produce recombinant cytokines, vaccines, antibodies, and other proteins, and rice (Oryza sativa) is a potential plant used as recombinant protein expression system. After successful transformation, transgenic rice cells can be either regenerated into whole plants or grown as cell cultures that can be upscaled into bioreactors. This review summarizes recent advances in the production of different recombinant protein produced in rice and describes their production methods as well as methods to improve protein yield and quality. Glycosylation and its impact in plant development and protein production are discussed, and several methods of improving yield and quality that have not been incorporated in rice expression systems are also proposed. Finally, different bioreactor options are explored and their advantages are analyzed. PMID:23615467

  14. Integrated analysis of toxicity data of two pharmaceutical immunosuppressants and two environmental pollutants with immunomodulating properties to improve the understanding of side effects-A toxicopathologist׳s view.

    PubMed

    Kuper, C Frieke; Vogels, Jack; Kemmerling, Jessica; Fehlert, Ellen; Rühl-Fehlert, Christine; Vohr, Hans-Werner; Krul, Cyrille

    2015-07-15

    Data in a toxicity test are evaluated generally per parameter. Information on the response per animal in addition to per parameter can improve the evaluation of the results. The results from the six studies in rats, described in the paper by Kemmerling, J., Fehlert, E., Rühl-Fehlert, C., Kuper, C.F., Stropp, G., Vogels, J., Krul, C., Vohr, H.-W., 2015. The transferability from rat subacute 4-week oral toxicity study to translational research exemplified by two pharmaceutical immunosuppressants and two environmental pollutants with immunomodulating properties (In this issue), have been subjected to principal component analysis (PCA) and principal component discriminant analysis (PC-DA). The two pharmaceuticals azathioprine (AZA) and cyclosporine A (CSA) and the two environmental pollutants hexachlorobenzene (HCB) and benzo(a)pyrene (BaP) all modulate the immune system, albeit that their mode of immunomodulation is quite diverse. PCA illustrated the similarities between the two independent studies with AZA (AZA1 and AZA2) and CSA (CSA1 and CSA2). The PC-DA on data of the AZA2 study did not increase substantially the information on dose levels. In general, the no-effect levels were lower upon single parameter analysis than indicated by the distances between the dose groups in the PCA. This was mostly due to the expert judgment in the single parameter evaluation, which took into account outstanding pathology in only one or two animals. The PCA plots did not reveal sex-related differences in sensitivity, but the key pathology for males and females differed. The observed variability in some of the control groups was largely a peripheral blood effect. Most importantly, PCA analysis identified several animals outside the 95% confidence limit indicating high-responders; also low-to-non-responders were identified. The key pathology enhanced the understanding of the response of the animals to the four model compounds. PMID:25824899

  15. Structure-Property Relationships of Solids in Pharmaceutical Processing

    NASA Astrophysics Data System (ADS)

    Chattoraj, Sayantan

    Pharmaceutical development and manufacturing of solid dosage forms is witnessing a seismic shift in the recent years. In contrast to the earlier days when drug development was empirical, now there is a significant emphasis on a more scientific and structured development process, primarily driven by the Quality-by-Design (QbD) initiatives of US Food and Drug Administration (US-FDA). Central to such an approach is the enhanced understanding of solid materials using the concept of Materials Science Tetrahedron (MST) that probes the interplay between four elements, viz., the structure, properties, processing, and performance of materials. In this thesis work, we have investigated the relationships between the structure and those properties of pharmaceutical solids that influence their processing behavior. In all cases, we have used material-sparing approaches to facilitate property assessment using very small sample size of materials, which is a pre-requisite in the early stages of drug development when the availability of materials, drugs in particular, is limited. The influence of solid structure, either at the molecular or bulk powder levels, on crystal plasticity and powder compaction, powder flow, and solid-state amorphization during milling, has been investigated in this study. Through such a systematic evaluation, we have captured the involvement of structure-property correlations within a wide spectrum of relevant processing behaviors of pharmaceutical solids. Such a holistic analysis will be beneficial for addressing both regulatory and scientific issues in drug development.

  16. Effects of Manufacturing Conditions on Pharmaceutical Properties of Petrolatum Ointment.

    PubMed

    Ashizuka, Yuki; Horisawa, Eijiro

    2016-08-01

    Oleaginous white petrolatum ointment (WP ointment) is one of the most commonly used dosage forms in the preparation of topical products. In general, WP ointments containing medium chain fatty acid triglycerides (MCT) are manufactured through a process of melting, mixing, agitating, and cooling. To investigate the pharmaceutical properties of WP ointments in greater detail, we examined manufacturing factors which could potentially influence the pharmaceutical properties of the finished product. WP ointment samples containing 10% MCT were stirred with a homogenizer and a paddle mixer at 65°C, then the homogenizer was stopped. Next, the paddle-mixer was stopped at several planned temperature points at which different samples were taken. Each sample was then cooled under the following planned conditions: rapid-cooling [-50°C/h] and slow-cooling [-7.5°C/h]. The pharmaceutical properties of each WP ointment sample, along with the appearance (Optical/digital microscope), hardness (Rheometer), and bleeding ability (100 Mesh wire-net cone) were measured. Then, release profiles were performed with a WP ointment using the model active ingredient Vitamin D. As a result, high hardness, low bleeding ability and low release profile were observed in the WP ointment samples that were manufactured under the condition of stopping the paddle-mixer at 40°C. However, the influence of cooling speed was observed to affect only hardness. Through optical microscopic observation, it was found that the appearance of WP ointment samples differed depending on the conditions under which they were manufactured. In this study, it was clear that the pharmaceutical properties of WP ointment samples were particularly influenced by the paddle-mixer stopping temperature. PMID:27193304

  17. Effects of Manufacturing Conditions on Pharmaceutical Properties of Petrolatum Ointment.

    PubMed

    Ashizuka, Yuki; Horisawa, Eijiro

    2016-08-01

    Oleaginous white petrolatum ointment (WP ointment) is one of the most commonly used dosage forms in the preparation of topical products. In general, WP ointments containing medium chain fatty acid triglycerides (MCT) are manufactured through a process of melting, mixing, agitating, and cooling. To investigate the pharmaceutical properties of WP ointments in greater detail, we examined manufacturing factors which could potentially influence the pharmaceutical properties of the finished product. WP ointment samples containing 10% MCT were stirred with a homogenizer and a paddle mixer at 65°C, then the homogenizer was stopped. Next, the paddle-mixer was stopped at several planned temperature points at which different samples were taken. Each sample was then cooled under the following planned conditions: rapid-cooling [-50°C/h] and slow-cooling [-7.5°C/h]. The pharmaceutical properties of each WP ointment sample, along with the appearance (Optical/digital microscope), hardness (Rheometer), and bleeding ability (100 Mesh wire-net cone) were measured. Then, release profiles were performed with a WP ointment using the model active ingredient Vitamin D. As a result, high hardness, low bleeding ability and low release profile were observed in the WP ointment samples that were manufactured under the condition of stopping the paddle-mixer at 40°C. However, the influence of cooling speed was observed to affect only hardness. Through optical microscopic observation, it was found that the appearance of WP ointment samples differed depending on the conditions under which they were manufactured. In this study, it was clear that the pharmaceutical properties of WP ointment samples were particularly influenced by the paddle-mixer stopping temperature.

  18. Impact of soil properties on selected pharmaceuticals adsorption in soils

    NASA Astrophysics Data System (ADS)

    Kodesova, Radka; Kocarek, Martin; Klement, Ales; Fer, Miroslav; Golovko, Oksana; Grabic, Roman; Jaksik, Ondrej

    2014-05-01

    The presence of human and veterinary pharmaceuticals in the environment has been recognized as a potential threat. Pharmaceuticals may contaminate soils and consequently surface and groundwater. Study was therefore focused on the evaluation of selected pharmaceuticals adsorption in soils, as one of the parameters, which are necessary to know when assessing contaminant transport in soils. The goals of this study were: (1) to select representative soils of the Czech Republic and to measure soil physical and chemical properties; (2) to measure adsorption isotherms of selected pharmaceuticals; (3) to evaluate impact of soil properties on pharmaceutical adsorptions and to propose pedotransfer rules for estimating adsorption coefficients from the measured soil properties. Batch sorption tests were performed for 6 selected pharmaceuticals (beta blockers Atenolol and Metoprolol, anticonvulsant Carbamazepin, and antibiotics Clarithromycin, Trimetoprim and Sulfamethoxazol) and 13 representative soils (soil samples from surface horizons of 11 different soil types and 2 substrates). The Freundlich equations were used to describe adsorption isotherms. The simple correlations between measured physical and chemical soil properties (soil particle density, soil texture, oxidable organic carbon content, CaCO3 content, pH_H2O, pH_KCl, exchangeable acidity, cation exchange capacity, hydrolytic acidity, basic cation saturation, sorption complex saturation, salinity), and the Freundlich adsorption coefficients were assessed using Pearson correlation coefficient. Then multiple-linear regressions were applied to predict the Freundlich adsorption coefficients from measured soil properties. The largest adsorption was measured for Clarithromycin (average value of 227.1) and decreased as follows: Trimetoprim (22.5), Metoprolol (9.0), Atenolol (6.6), Carbamazepin (2.7), Sulfamethoxazol (1.9). Absorption coefficients for Atenolol and Metoprolol closely correlated (R=0.85), and both were also

  19. Intellectual property rights: An overview and implications in pharmaceutical industry

    PubMed Central

    Saha, Chandra Nath; Bhattacharya, Sanjib

    2011-01-01

    Intellectual property rights (IPR) have been defined as ideas, inventions, and creative expressions based on which there is a public willingness to bestow the status of property. IPR provide certain exclusive rights to the inventors or creators of that property, in order to enable them to reap commercial benefits from their creative efforts or reputation. There are several types of intellectual property protection like patent, copyright, trademark, etc. Patent is a recognition for an invention, which satisfies the criteria of global novelty, non-obviousness, and industrial application. IPR is prerequisite for better identification, planning, commercialization, rendering, and thereby protection of invention or creativity. Each industry should evolve its own IPR policies, management style, strategies, and so on depending on its area of specialty. Pharmaceutical industry currently has an evolving IPR strategy requiring a better focus and approach in the coming era. PMID:22171299

  20. [Adhesive properties and related phenomena for powdered pharmaceuticals].

    PubMed

    Otsuka, A

    1998-04-01

    This report deals with adhesive properties and related phenomena of powdered materials including pharmaceuticals. The adhesive force between a powder particle and substrate as well as the tensile strength of a powder bed and tablet was measured. Various factors were found to affect powder adhesion. Physical properties such as the size, shape and surface roughness were examined. The adhesive force between a particle and substrate decreased remarkably in the presence of ultrafine particles, which is of interest since the addition of adequate amount of "glidant" causes an increase in powder fluidity. From a pharmaceutical point of view, temperature and humidity were essential to particle adhesion. For several organic substances, the adhesive force increased significantly at homologous temperatures more than ca. 0.7, suggesting the sintering mechanism to be operative. The adhsive force between polymer films and glass beads varied according to polymer and relative humidity. A close correlation of water sorbed by the polymer film with adhesive force was noted. In connection with powder fluidity, compaction properties were studied by the centrifugal and tapping methods. Apparent adhesion defined as the ratio of the adhesive force between two contacting particles to the external force acting on a particle was noted to be the primary determinant of the void fraction or the porosity of the powder bed, indicating that the probability of particle displacement essentially depended on apparent adhesion.

  1. Antisolvent precipitation of novel xylitol-additive crystals to engineer tablets with improved pharmaceutical performance.

    PubMed

    Kaialy, Waseem; Maniruzzaman, Mohammad; Shojaee, Saeed; Nokhodchi, Ali

    2014-12-30

    The purpose of this work was to develop stable xylitol particles with modified physical properties, improved compactibility and enhanced pharmaceutical performance without altering polymorphic form of xylitol. Xylitol was crystallized using antisolvent crystallization technique in the presence of various hydrophilic polymer additives, i.e., polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA) at a range of concentrations. The crystallization process did not influence the stable polymorphic form or true density of xylitol. However, botryoidal-shaped crystallized xylitols demonstrated different particle morphologies and lower powder bulk and tap densities in comparison to subangular-shaped commercial xylitol. Xylitol crystallized without additive and xylitol crystallized in the presence of PVP or PVA demonstrated significant improvement in hardness of directly compressed tablets; however, such improvement was observed to lesser extent for xylitol crystallized in the presence of PEG. Crystallized xylitols produced enhanced dissolution profiles for indomethacin in comparison to original xylitol. The influence of additive concentration on tablet hardness was dependent on the type of additive, whereas an increased concentration of all additives provided an improvement in the dissolution behavior of indomethacin. Antisolvent crystallization using judiciously selected type and concentration of additive can be a potential approach to prepare xylitol powders with promising physicomechanical and pharmaceutical properties.

  2. Improvement of flow and bulk density of pharmaceutical powders using surface modification.

    PubMed

    Jallo, Laila J; Ghoroi, Chinmay; Gurumurthy, Lakxmi; Patel, Utsav; Davé, Rajesh N

    2012-02-28

    Improvement in flow and bulk density, the two most important properties that determine the ease with which pharmaceutical powders can be handled, stored and processed, is done through surface modification. A limited design of experiment was conducted to establish a standardized dry coating procedure that limits the extent of powder attrition, while providing the most consistent improvement in angle of repose (AOR). The magnetically assisted impaction coating (MAIC) was considered as a model dry-coater for pharmaceutical powders; ibuprofen, acetaminophen, and ascorbic acid. Dry coated drug powders were characterized by AOR, particle size as a function of dispersion pressure, particle size distribution, conditioned bulk density (CBD), Carr index (CI), flow function coefficient (FFC), cohesion coefficient using different instruments, including a shear cell in the Freeman FT4 powder rheometer, and Hansen flowability index. Substantial improvement was observed in all the measured properties after dry coating relative to the uncoated powders, such that each powder moved from a poorer to a better flow classification and showed improved dispersion. The material intrinsic property such as cohesion, plotted as a function of particle size, gave a trend similar to those of bulk flow properties, AOR and CI. Property improvement is also illustrated in a phase map of inverse cohesion (or FFC) as a function of bulk density, which also indicated a significant positive shift due to dry coating. It is hoped that such phase maps are useful in manufacturing decisions regarding the need for dry coating, which will allow moving from wet granulation to roller compaction or to direct compression based formulations. PMID:22197769

  3. Improvement of flow and bulk density of pharmaceutical powders using surface modification.

    PubMed

    Jallo, Laila J; Ghoroi, Chinmay; Gurumurthy, Lakxmi; Patel, Utsav; Davé, Rajesh N

    2012-02-28

    Improvement in flow and bulk density, the two most important properties that determine the ease with which pharmaceutical powders can be handled, stored and processed, is done through surface modification. A limited design of experiment was conducted to establish a standardized dry coating procedure that limits the extent of powder attrition, while providing the most consistent improvement in angle of repose (AOR). The magnetically assisted impaction coating (MAIC) was considered as a model dry-coater for pharmaceutical powders; ibuprofen, acetaminophen, and ascorbic acid. Dry coated drug powders were characterized by AOR, particle size as a function of dispersion pressure, particle size distribution, conditioned bulk density (CBD), Carr index (CI), flow function coefficient (FFC), cohesion coefficient using different instruments, including a shear cell in the Freeman FT4 powder rheometer, and Hansen flowability index. Substantial improvement was observed in all the measured properties after dry coating relative to the uncoated powders, such that each powder moved from a poorer to a better flow classification and showed improved dispersion. The material intrinsic property such as cohesion, plotted as a function of particle size, gave a trend similar to those of bulk flow properties, AOR and CI. Property improvement is also illustrated in a phase map of inverse cohesion (or FFC) as a function of bulk density, which also indicated a significant positive shift due to dry coating. It is hoped that such phase maps are useful in manufacturing decisions regarding the need for dry coating, which will allow moving from wet granulation to roller compaction or to direct compression based formulations.

  4. Innovative pharmaceutical development based on unique properties of nanoscale delivery formulation.

    PubMed

    Kumar, Anil; Chen, Fei; Mozhi, Anbu; Zhang, Xu; Zhao, Yuanyuan; Xue, Xiangdong; Hao, Yanli; Zhang, Xiaoning; Wang, Paul C; Liang, Xing-Jie

    2013-09-21

    The advent of nanotechnology has reignited interest in the field of pharmaceutical science for the development of nanomedicine. Nanomedicinal formulations are nanometer-sized carrier materials designed for increasing the drug tissue bioavailability, thereby improving the treatment of systemically applied chemotherapeutic drugs. Nanomedicine is a new approach to deliver the pharmaceuticals through different routes of administration with safer and more effective therapies compared to conventional methods. To date, various kinds of nanomaterials have been developed over the years to make delivery systems more effective for the treatment of various diseases. Even though nanomaterials have significant advantages due to their unique nanoscale properties, there are still significant challenges in the improvement and development of nanoformulations with composites and other materials. Here in this review, we highlight the nanomedicinal formulations aiming to improve the balance between the efficacy and the toxicity of therapeutic interventions through different routes of administration and how to design nanomedicine for safer and more effective ways to improve the treatment quality. We also emphasize the environmental and health prospects of nanomaterials for human health care.

  5. Innovative pharmaceutical development based on unique properties of nanoscale delivery formulation

    NASA Astrophysics Data System (ADS)

    Kumar, Anil; Chen, Fei; Mozhi, Anbu; Zhang, Xu; Zhao, Yuanyuan; Xue, Xiangdong; Hao, Yanli; Zhang, Xiaoning; Wang, Paul C.; Liang, Xing-Jie

    2013-08-01

    The advent of nanotechnology has reignited interest in the field of pharmaceutical science for the development of nanomedicine. Nanomedicinal formulations are nanometer-sized carrier materials designed for increasing the drug tissue bioavailability, thereby improving the treatment of systemically applied chemotherapeutic drugs. Nanomedicine is a new approach to deliver the pharmaceuticals through different routes of administration with safer and more effective therapies compared to conventional methods. To date, various kinds of nanomaterials have been developed over the years to make delivery systems more effective for the treatment of various diseases. Even though nanomaterials have significant advantages due to their unique nanoscale properties, there are still significant challenges in the improvement and development of nanoformulations with composites and other materials. Here in this review, we highlight the nanomedicinal formulations aiming to improve the balance between the efficacy and the toxicity of therapeutic interventions through different routes of administration and how to design nanomedicine for safer and more effective ways to improve the treatment quality. We also emphasize the environmental and health prospects of nanomaterials for human health care.

  6. Innovative pharmaceutical development based on unique properties of nanoscale delivery formulation

    PubMed Central

    Mozhi, Anbu; Zhang, Xu; Zhao, Yuanyuan; Xue, Xiangdong; Hao, Yanli; Zhang, Xiaoning; Wang, Paul C.; Liang, Xing-Jie

    2014-01-01

    The advent of nanotechnology has reignited interest in the field of pharmaceutical science for the development of nanomedicine. Nanomedicinal formulations are nanometer-sized carrier materials designed for increasing the drug tissue bioavailability, thereby improving the treatment of systemically applied chemotherapeutic drugs. Nanomedicine is a new approach to deliver the pharmaceuticals through different routes of administration with safer and more effective therapies compared to conventional methods. To date, various kinds of nanomaterials have been developed over the years to make delivery systems more effective for the treatment of various diseases. Even though nanomaterials have significant advantages due to their unique nanoscale properties, there are still significant challenges in the improvement and development of nanoformulations with composites and other materials. Here in this review, we highlight the nanomedicinal formulations aiming to improve the balance between the efficacy and the toxicity of therapeutic interventions through different routes of administration and how to design nanomedicine for safer and more effective ways to improve the treatment quality. We also emphasize the environmental and health prospects of nanomaterials for human health care. PMID:23860639

  7. Determination of flow properties of pharmaceutical powders by near infrared spectroscopy.

    PubMed

    Sarraguça, Mafalda C; Cruz, Ana V; Soares, Sandra O; Amaral, Helena R; Costa, Paulo C; Lopes, João A

    2010-08-01

    The physical properties of pharmaceutical powders are of upmost importance in the pharmaceutical industry. The knowledge of their flow properties is of critical significance in operations such as blending, tablet compression, capsule filling, transportation, and in scale-up operations. Powders flow properties are measured using a number of parameters such as, angle of repose, compressibility index (Carr's index) and Hausner ratio. To estimate these properties, specific and expensive equipment with time-consuming analysis is required. Near infrared spectroscopy is a fast and low-cost analytical technique thoroughly used in the pharmaceutical industry in the quantification and qualification of products. To establish the potential of this technique to determine the parameters associated with the flow properties of pharmaceutical powders, blended powders based on paracetamol as the active pharmaceutical ingredient were constructed in pilot scale. Spectra were recorded on a Fourier-transform near infrared spectrometer in reflectance mode. The parameters studied were the angle of repose, aerated and tapped bulk density. The correlation between the reference method values and the near infrared spectrum was performed by partial least squares and optimized in terms of latent variables using cross-validation. The near infrared based properties predictions were compared with the reference methods results. Prediction errors, which varied between 2.35% for the angle of repose, 2.51% for the tapped density and 3.18% for the aerated density, show the potential of NIR spectroscopy in the determination of physical properties affecting the flowability of pharmaceutical powders.

  8. Effect of colloidal silica on rheological properties of common pharmaceutical excipients.

    PubMed

    Majerová, Diana; Kulaviak, Lukáš; Růžička, Marek; Štěpánek, František; Zámostný, Petr

    2016-09-01

    In pharmaceutical industry, the use of lubricants is mostly based on historical experiences or trial and error methods even these days. It may be demanding in terms of the material consumption and may result in sub-optimal drug composition. Powder rheology enables more accurate monitoring of the flow properties and because the measurements need only a small sample it is perfectly suitable for the rare or expensive substances. In this work, rheological properties of four common excipients (pregelatinized maize starch, microcrystalline cellulose, croscarmellose sodium and magnesium stearate) were studied by the FT4 Powder Rheometer, which was used for measuring the compressibility index by a piston and flow properties of the powders by a rotational shear cell. After an initial set of measurements, two excipients (pregelatinized maize starch and microcrystalline cellulose) were chosen and mixed, in varying amounts, with anhydrous colloidal silicon dioxide (Aerosil 200) used as a glidant. The bulk (conditioned and compressed densities, compressibility index), dynamic (basic flowability energy) and shear (friction coefficient, flow factor) properties were determined to find an optimum ratio of the glidant. Simultaneously, the particle size data were obtained using a low-angle laser light scattering (LALLS) system and scanning electron microscopy was performed in order to examine the relationship between the rheological properties and the inner structure of the materials. The optimum of flowability for the mixture composition was found, to correspond to empirical findings known from general literature. In addition the mechanism of colloidal silicone dioxide action to improve flowability was suggested and the hypothesis was confirmed by independent test. New findings represent a progress towards future application of determining the optimum concentration of glidant from the basic characteristics of the powder in the pharmaceutical research and development.

  9. Effect of colloidal silica on rheological properties of common pharmaceutical excipients.

    PubMed

    Majerová, Diana; Kulaviak, Lukáš; Růžička, Marek; Štěpánek, František; Zámostný, Petr

    2016-09-01

    In pharmaceutical industry, the use of lubricants is mostly based on historical experiences or trial and error methods even these days. It may be demanding in terms of the material consumption and may result in sub-optimal drug composition. Powder rheology enables more accurate monitoring of the flow properties and because the measurements need only a small sample it is perfectly suitable for the rare or expensive substances. In this work, rheological properties of four common excipients (pregelatinized maize starch, microcrystalline cellulose, croscarmellose sodium and magnesium stearate) were studied by the FT4 Powder Rheometer, which was used for measuring the compressibility index by a piston and flow properties of the powders by a rotational shear cell. After an initial set of measurements, two excipients (pregelatinized maize starch and microcrystalline cellulose) were chosen and mixed, in varying amounts, with anhydrous colloidal silicon dioxide (Aerosil 200) used as a glidant. The bulk (conditioned and compressed densities, compressibility index), dynamic (basic flowability energy) and shear (friction coefficient, flow factor) properties were determined to find an optimum ratio of the glidant. Simultaneously, the particle size data were obtained using a low-angle laser light scattering (LALLS) system and scanning electron microscopy was performed in order to examine the relationship between the rheological properties and the inner structure of the materials. The optimum of flowability for the mixture composition was found, to correspond to empirical findings known from general literature. In addition the mechanism of colloidal silicone dioxide action to improve flowability was suggested and the hypothesis was confirmed by independent test. New findings represent a progress towards future application of determining the optimum concentration of glidant from the basic characteristics of the powder in the pharmaceutical research and development. PMID:27163240

  10. Improving efficiencies in pharmaceutical distribution channels using the economic order quantity model.

    PubMed

    Sullivan, D L; Schommer, J C

    1993-01-01

    The purpose of this study was to investigate empirically the potential cost savings to a pharmaceutical wholesaler using the Economic Order Quantity (EOQ) model. This model allows for calculating the order quantity that minimizes both ordering and holding costs. A regional pharmaceutical wholesaler was selected for a case analysis study using the EOQ model. Eleven brand name products were randomly selected for the analysis. The average yearly cost savings using EOQ was $31.92 per product. The potential yearly cost savings based on 8500 brand name stock-keeping units was $271,320. Using EOQ can therefore assist pharmaceutical wholesalers in minimizing holding and ordering costs and improve efficiency for pharmaceutical distribution channels.

  11. Impacts of compound properties and sediment characteristics on the sorption behaviour of pharmaceuticals in aquatic systems.

    PubMed

    Al-Khazrajy, Omar S A; Boxall, Alistair B A

    2016-11-01

    Sorption is a key factor in determining the persistence, attenuation and bioavailability of sediment-associated contaminants. However, our understanding of the sorption behaviour of pharmaceuticals in sediments is poor. In this study, we investigated the sorption behaviour of a diverse set of pharmaceuticals in a range sediment types. Sorption affinity of pharmaceuticals for all sediments was found to increase in the order mefenamic acidpharmaceuticals. Multiple linear regression analysis was therefore used to develop new models for estimating sorption of individual pharmaceuticals based on sediment properties. The analyses indicated that sorption is related to properties such as Log Dow of a compound in the sediment (lipophilicity corrected for the sediment pH), cation exchange capacity, clay%, organic carbon content and exchangeable Ca(2+), although, with the exception of atenolol, robust relationships between sediment properties and sorption were not obtained. Overall, the results demonstrate how complex the processes are that drive the sorption of pharmaceuticals in sediments and highlight the need for generation of further experimental data and further model development work. PMID:27270139

  12. Impacts of compound properties and sediment characteristics on the sorption behaviour of pharmaceuticals in aquatic systems.

    PubMed

    Al-Khazrajy, Omar S A; Boxall, Alistair B A

    2016-11-01

    Sorption is a key factor in determining the persistence, attenuation and bioavailability of sediment-associated contaminants. However, our understanding of the sorption behaviour of pharmaceuticals in sediments is poor. In this study, we investigated the sorption behaviour of a diverse set of pharmaceuticals in a range sediment types. Sorption affinity of pharmaceuticals for all sediments was found to increase in the order mefenamic acidpharmaceuticals. Multiple linear regression analysis was therefore used to develop new models for estimating sorption of individual pharmaceuticals based on sediment properties. The analyses indicated that sorption is related to properties such as Log Dow of a compound in the sediment (lipophilicity corrected for the sediment pH), cation exchange capacity, clay%, organic carbon content and exchangeable Ca(2+), although, with the exception of atenolol, robust relationships between sediment properties and sorption were not obtained. Overall, the results demonstrate how complex the processes are that drive the sorption of pharmaceuticals in sediments and highlight the need for generation of further experimental data and further model development work.

  13. Effects of soil properties on the uptake of pharmaceuticals into earthworms.

    PubMed

    Carter, Laura J; Ryan, Jim J; Boxall, Alistair B A

    2016-06-01

    Pharmaceuticals can enter the soil environment when animal slurries and sewage sludge are applied to land as a fertiliser or during irrigation with contaminated water. These pharmaceuticals may then be taken up by soil organisms possibly resulting in toxic effects and/or exposure of organisms higher up the food chain. This study investigated the influence of soil properties on the uptake and depuration of pharmaceuticals (carbamazepine, diclofenac, fluoxetine and orlistat) in the earthworm Eisenia fetida. The uptake and accumulation of pharmaceuticals into E. fetida changed depending on soil type. Orlistat exhibited the highest pore water based bioconcentration factors (BCFs) and displayed the largest differences between soil types with BCFs ranging between 30.5 and 115.9. For carbamazepine, diclofenac and fluoxetine BCFs ranged between 1.1 and 1.6, 7.0 and 69.6 and 14.1 and 20.4 respectively. Additional analysis demonstrated that in certain treatments the presence of these chemicals in the soil matrices changed the soil pH over time, with a statistically significant pH difference to control samples. The internal pH of E. fetida also changed as a result of incubation in pharmaceutically spiked soil, in comparison to the control earthworms. These results demonstrate that a combination of soil properties and pharmaceutical physico-chemical properties are important in terms of predicting pharmaceutical uptake in terrestrial systems and that pharmaceuticals can modify soil and internal earthworm chemistry which may hold wider implications for risk assessment. PMID:27049789

  14. Effects of soil properties on the uptake of pharmaceuticals into earthworms.

    PubMed

    Carter, Laura J; Ryan, Jim J; Boxall, Alistair B A

    2016-06-01

    Pharmaceuticals can enter the soil environment when animal slurries and sewage sludge are applied to land as a fertiliser or during irrigation with contaminated water. These pharmaceuticals may then be taken up by soil organisms possibly resulting in toxic effects and/or exposure of organisms higher up the food chain. This study investigated the influence of soil properties on the uptake and depuration of pharmaceuticals (carbamazepine, diclofenac, fluoxetine and orlistat) in the earthworm Eisenia fetida. The uptake and accumulation of pharmaceuticals into E. fetida changed depending on soil type. Orlistat exhibited the highest pore water based bioconcentration factors (BCFs) and displayed the largest differences between soil types with BCFs ranging between 30.5 and 115.9. For carbamazepine, diclofenac and fluoxetine BCFs ranged between 1.1 and 1.6, 7.0 and 69.6 and 14.1 and 20.4 respectively. Additional analysis demonstrated that in certain treatments the presence of these chemicals in the soil matrices changed the soil pH over time, with a statistically significant pH difference to control samples. The internal pH of E. fetida also changed as a result of incubation in pharmaceutically spiked soil, in comparison to the control earthworms. These results demonstrate that a combination of soil properties and pharmaceutical physico-chemical properties are important in terms of predicting pharmaceutical uptake in terrestrial systems and that pharmaceuticals can modify soil and internal earthworm chemistry which may hold wider implications for risk assessment.

  15. Review: Chios mastic gum: a plant-produced resin exhibiting numerous diverse pharmaceutical and biomedical properties.

    PubMed

    Dimas, Konstantinos S; Pantazis, Panayotis; Ramanujam, Rama

    2012-01-01

    Chios mastic gum (CMG) is a resin produced by the plant Pistacia lentiscus var. chia. CMG is used to extract the mastic gum essential oil (MGO). CMG and MGO consist of nearly 70 constituents and have demonstrated numerous and diverse biomedical and pharmacological properties including (a) eradication of bacteria and fungi that may cause peptic ulcers, tooth plaque formation and malodor of the mouth and saliva; (b) amelioration or dramatic reduction of symptoms of autoimmune diseases by inhibiting production of pro-inflammatory substances by activated macrophages, production of cytokines by peripheral blood mononuclear cells in patients with active Crohn's disease, and suppression of production of inflammatory cytokines and chemokines in an asthma model in mice; (c) protection of the cardiovascular system by effectively lowering the levels of total serum cholesterol, low-density lipoprotein and triglycerides in rats, and protection of low-density lipoprotein from oxidation in humans; (d) induction of apoptosis in human cancer cells in vitro and extensive inhibition of growth of human tumors xenografted in immunodeficient mice; and (e) improvement of symptoms in patients with functional dyspepsia. Collectively taken, these numerous and diverse medical and pharmaceutical properties of CMG and MGO warrant further research in an effort to enhance specific properties and identify specific constituent(s) that might be associated with each property. PMID:22949590

  16. Review: Chios mastic gum: a plant-produced resin exhibiting numerous diverse pharmaceutical and biomedical properties.

    PubMed

    Dimas, Konstantinos S; Pantazis, Panayotis; Ramanujam, Rama

    2012-01-01

    Chios mastic gum (CMG) is a resin produced by the plant Pistacia lentiscus var. chia. CMG is used to extract the mastic gum essential oil (MGO). CMG and MGO consist of nearly 70 constituents and have demonstrated numerous and diverse biomedical and pharmacological properties including (a) eradication of bacteria and fungi that may cause peptic ulcers, tooth plaque formation and malodor of the mouth and saliva; (b) amelioration or dramatic reduction of symptoms of autoimmune diseases by inhibiting production of pro-inflammatory substances by activated macrophages, production of cytokines by peripheral blood mononuclear cells in patients with active Crohn's disease, and suppression of production of inflammatory cytokines and chemokines in an asthma model in mice; (c) protection of the cardiovascular system by effectively lowering the levels of total serum cholesterol, low-density lipoprotein and triglycerides in rats, and protection of low-density lipoprotein from oxidation in humans; (d) induction of apoptosis in human cancer cells in vitro and extensive inhibition of growth of human tumors xenografted in immunodeficient mice; and (e) improvement of symptoms in patients with functional dyspepsia. Collectively taken, these numerous and diverse medical and pharmaceutical properties of CMG and MGO warrant further research in an effort to enhance specific properties and identify specific constituent(s) that might be associated with each property.

  17. Improved metabolites of pharmaceutical ingredient grade Ginkgo biloba and the correlated proteomics analysis.

    PubMed

    Zheng, Wen; Li, Ximin; Zhang, Lin; Zhang, Yanzhen; Lu, Xiaoping; Tian, Jingkui

    2015-06-01

    Ginkgo biloba is an attractive and traditional medicinal plant, and has been widely used as a phytomedicine in the prevention and treatment of cardiovascular and cerebrovascular diseases. Flavonoids and terpene lactones are the major bioactive components of Ginkgo, whereas the ginkgolic acids (GAs) with strong allergenic properties are strictly controlled. In this study, we tested the content of flavonoids and GAs under ultraviolet-B (UV-B) treatment and performed comparative proteomic analyses to determine the differential proteins that occur upon UV-B radiation. That might play a crucial role in producing flavonoids and GAs. Our phytochemical analyses demonstrated that UV-B irradiation significantly increased the content of active flavonoids, and decreased the content of toxic GAs. We conducted comparative proteomic analysis of both whole leaf and chloroplasts proteins. In total, 27 differential proteins in the whole leaf and 43 differential proteins in the chloroplast were positively identified and functionally annotated. The proteomic data suggested that enhanced UV-B radiation exposure activated antioxidants and stress-responsive proteins as well as reduced the rate of photosynthesis. We demonstrate that UV-B irradiation pharmaceutically improved the metabolic ingredients of Ginkgo, particularly in terms of reducing GAs. With high UV absorption properties, and antioxidant activities, the flavonoids were likely highly induced as protective molecules following UV-B irradiation.

  18. Improved metabolites of pharmaceutical ingredient grade Ginkgo biloba and the correlated proteomics analysis.

    PubMed

    Zheng, Wen; Li, Ximin; Zhang, Lin; Zhang, Yanzhen; Lu, Xiaoping; Tian, Jingkui

    2015-06-01

    Ginkgo biloba is an attractive and traditional medicinal plant, and has been widely used as a phytomedicine in the prevention and treatment of cardiovascular and cerebrovascular diseases. Flavonoids and terpene lactones are the major bioactive components of Ginkgo, whereas the ginkgolic acids (GAs) with strong allergenic properties are strictly controlled. In this study, we tested the content of flavonoids and GAs under ultraviolet-B (UV-B) treatment and performed comparative proteomic analyses to determine the differential proteins that occur upon UV-B radiation. That might play a crucial role in producing flavonoids and GAs. Our phytochemical analyses demonstrated that UV-B irradiation significantly increased the content of active flavonoids, and decreased the content of toxic GAs. We conducted comparative proteomic analysis of both whole leaf and chloroplasts proteins. In total, 27 differential proteins in the whole leaf and 43 differential proteins in the chloroplast were positively identified and functionally annotated. The proteomic data suggested that enhanced UV-B radiation exposure activated antioxidants and stress-responsive proteins as well as reduced the rate of photosynthesis. We demonstrate that UV-B irradiation pharmaceutically improved the metabolic ingredients of Ginkgo, particularly in terms of reducing GAs. With high UV absorption properties, and antioxidant activities, the flavonoids were likely highly induced as protective molecules following UV-B irradiation. PMID:25604066

  19. Pharmaceutical services as a tool to improve outcomes in patients with cardiovascular diseases.

    PubMed

    Swieczkowski, Damian; Mogielnicki, Mariusz; Merks, Piotr; Gruchala, Marcin; Jaguszewski, Milosz

    2016-11-01

    Despite the presence of effective and safe pharmacotherapy, and availability of multidimensional non-pharmacological treatment, the overall rate of major adverse cardiovascular outcomes remains still unsatisfactory. The clinical pharmacy activities and pharmaceutical care available in the community pharmacy settings have a significant impact on outcomes in cardiovascular patients, e.g. adherence, the level of blood pressure, total cholesterol or patients' health literacy. Pharmaceutical care in patients diagnosed with cardiovascular diseases remains beneficial both to the patients and the entire health care system. However, the prediction of results of pharmacists' interventions is particularly difficult and random. Many factors contribute to outcomes of community pharmacy services, e.g. time spent with the patients or quality of communication between patients and healthcare professionals. The most important issue in delivering effective pharmaceutical care is to develop an evidence-based model. Globally, the development of interprofessional collaboration between physicians and pharmacists, and preparing more sophisticated pharmacoeconomics analyses in the scope of pharmaceutical care are the next step in the improvement of advanced pharmaceutical services. Further research, particularly based on real data on this highly interesting topic is needed and recommended.

  20. Characterization and adsorptive properties of pharmaceutical grade clays.

    PubMed

    Browne, J E; Feldkamp, J R; White, J L; Hem, S L

    1980-07-01

    The adsorption of tetracycline by clays commonly used in pharmacy can be predicted if the identity and character of the commerical clay sample are established. X-ray diffraction. IR spectroscopy, and chemical analysis were used to identify the clay component and any nonclay diluents present in a series of commerical pharmaceutical grade clays. The major clay components were montmorillonite, hectorite, attapulgite, saponite, and kaolinite. The clay structure, the nature of the exchangeable cation, and the presence of nonclay components are important factors affecting the tetracycline-clay interaction. In general, clay structures with a high surface charge lead to a greater interaction with the protonated form of tetracycline, while interaction with the zwitterionic form of tetracycline occurs in clay structures with minimal surface charge. The presence of multivalent, exchangeable cations on the clay surface diminishes interaction with the protonated form of tetracycline. Nonclay components such as calcite and dolomite increase the interactions of the zwitterionic and anionic forms of tetracycline with the clay.

  1. Drug delivery systems improve pharmaceutical profile and facilitate medication adherence.

    PubMed

    Wertheimer, Albert I; Santella, Thomas M; Finestone, Albert J; Levy, Richard A

    2005-01-01

    Innovations in dosage forms and dose delivery systems across a wide range of medications offer substantial clinical advantages, including reduced dosing frequency and improved patient adherence; minimized fluctuation of drug concentrations and maintenance of blood levels within a desired range; localized drug delivery; and the potential for reduced adverse effects and increased safety. The advent of new large-molecule drugs for previously untreatable or only partially treatable diseases is stimulating the development of suitable delivery systems for these agents. Although advanced formulations may be more expensive than conventional dosage forms, they often have a more favorable pharmacologic profile and can be cost-effective. Inclusion of these dosage forms on drug formulary lists may help patients remain on therapy and reduce the economic and social burden of care.

  2. [Examination of the properties of amphotensides with potential use as pharmaceuticals].

    PubMed

    Bialik, W

    1992-01-01

    Basic biological, surface-active and emulsifying properties of manufactured amphotensides in comparison with commercial products have been determined. It has been shown that the compounds investigated should be utilized as auxiliary substances in pharmaceutical technology. There is especially advisable to apply them as emulsifiers for o/w emulsions. PMID:8769083

  3. Pharmaceutical properties of freeze-dried formulations of egg albumin, several drugs and olive oil.

    PubMed

    Tsuji, Y; Kakegawa, H; Miyataka, H; Nishiki, M; Matsumoto, H; Satoh, T

    1996-04-01

    The freeze-dried ternary formulations of meclizine (MZ, an anti-motion sickness drug), prednisolone (PRED, an anti-inflammatory drug) and norfloxacin (NFLX, an anti-microbial drug) which are poorly water-soluble and are low bioavailability drugs, were prepared using egg albumin and olive oil. The powder X-ray diffractions, the dissolution rate and the bioavailabilities in vivo of these formulations were studied in comparison with each drug alone. By forming ternary formulations of these drugs, the dissolution rates of the drugs from the formulations were significantly improved compared with each drug alone. The results of their powder X-ray diffraction measurements showed that these drugs in the ternary formulations presented in an amorphous form, indicating increased dissolution rates. On the other hand, the plasma concentrations of these drugs increased significantly after oral administration in formulations to rats, except for the NFLX formulation, and the areas under the concentration-time curves (AUC) of the ternary formulations of MZ, PRED and NFLX were 2.1, 1.6 and 1.3 times those of the drugs alone, respectively. From these results, it was proven that formulations consisting of egg albumin, olive oil and poorly water-soluble drugs were useful preparations for improving the drug's disadvantageous pharmaceutical properties. PMID:9132174

  4. Managing the interface with marketing to improve delivery of pharmacovigilance within the pharmaceutical industry.

    PubMed

    Edwards, Brian

    2004-01-01

    The pharmaceutical industry is under pressure to improve the scientific quality of its decisions concerning the benefit and risks of its products while ensuring compliance with acceptable standards of marketing. All those in a pharmaceutical company who currently work within pharmacovigilance should be encouraged to lead from the front to examine ongoing marketing activities to see how they can be adapted more towards pharmacovigilance and risk management. The current irony is that the personnel who have the greatest influence on benefit-risk decisions of a product are not necessarily those who acknowledge that they are performing pharmacovigilance. Indeed, for all concerned, whether their orientation is scientific and commercial, effective communication with prescribers and consumers usually underpins product success. Also, a substantial 'marketing' budget is culturally acceptable for the pharmaceutical industry so it is logical to assume that resource for postmarketing activity is often made available. Given these realities, I suggest we should strive for an integrated marketing and risk-management plan based on the best available evidence and that being fully aware and in control of the safety issues for your products is the best way to commercialise them successfully. This approach can still be consistent with other corporate responsibilities such as trying to reduce the financial burden of product development. If this article stimulates further debate about how the pharmaceutical industry can more effectively organise resources and operations to support pharmacovigilance, risk management, and marketing, then it will have achieved its purpose.

  5. Managing the interface with marketing to improve delivery of pharmacovigilance within the pharmaceutical industry.

    PubMed

    Edwards, Brian

    2004-01-01

    The pharmaceutical industry is under pressure to improve the scientific quality of its decisions concerning the benefit and risks of its products while ensuring compliance with acceptable standards of marketing. All those in a pharmaceutical company who currently work within pharmacovigilance should be encouraged to lead from the front to examine ongoing marketing activities to see how they can be adapted more towards pharmacovigilance and risk management. The current irony is that the personnel who have the greatest influence on benefit-risk decisions of a product are not necessarily those who acknowledge that they are performing pharmacovigilance. Indeed, for all concerned, whether their orientation is scientific and commercial, effective communication with prescribers and consumers usually underpins product success. Also, a substantial 'marketing' budget is culturally acceptable for the pharmaceutical industry so it is logical to assume that resource for postmarketing activity is often made available. Given these realities, I suggest we should strive for an integrated marketing and risk-management plan based on the best available evidence and that being fully aware and in control of the safety issues for your products is the best way to commercialise them successfully. This approach can still be consistent with other corporate responsibilities such as trying to reduce the financial burden of product development. If this article stimulates further debate about how the pharmaceutical industry can more effectively organise resources and operations to support pharmacovigilance, risk management, and marketing, then it will have achieved its purpose. PMID:15154832

  6. Excipient foods: designing food matrices that improve the oral bioavailability of pharmaceuticals and nutraceuticals.

    PubMed

    McClements, David Julian; Xiao, Hang

    2014-07-25

    The oral bioavailability of many lipophilic bioactive agents (pharmaceuticals and nutraceuticals) is limited due to various physicochemical and physiological processes: poor release from food or drug matrices; low solubility in gastrointestinal fluids; metabolism or chemical transformation within the gastrointestinal tract; low epithelium cell permeability. The bioavailability of these agents can be improved by specifically designing food matrices that control their release, solubilization, transport, metabolism, and absorption within the gastrointestinal tract. This article discusses the impact of food composition and structure on oral bioavailability, and how this knowledge can be used to design excipient foods for improving the oral bioavailability of lipophilic bioactives. Excipient foods contain ingredients or structures that may have no bioactivity themselves, but that are able to promote the bioactivity of co-ingested bioactives. These bioactives may be lipophilic drugs in pharmaceutical preparations (such as capsules, pills, or syrups) or nutraceuticals present within food matrices (such as natural or processed foods and beverages). PMID:24760211

  7. Intellectual property rights and the Canadian pharmaceutical marketplace: where do we go from here?

    PubMed

    Lexchin, Joel

    2005-01-01

    Patent protection for prescription drugs has a long and contentious history in Canada. Bills C-22 and C-91, passed as part of Canada's commitment to various trade deals, first weakened and then abolished compulsory licensing. In order to decide on a future course of action that Canada should take on intellectual property rights (IPRs), it is useful to review downstream effects that resulted from C-22 and C-91. This article examines changes to employment, Canada's balance of trade in pharmaceuticals, investment in research and development, and drug expenditures. The author then reviews the arguments advanced by the pharmaceutical industry in favor of stronger protection for IPRs, the recent complaints made against Canada at the World Trade Organization regarding pharmaceutical IPRs, and the continuing argument about the "evergreening" of patents. Also discussed are the second-draft text agreement of the Free Trade Area of the Americas, which will, if implemented, have significant repercussions for pharmaceutical IPRs in Canada, and some ways in which patents distort the marketplace for drugs. The article concludes with some alternative recommendations on the future of IPRs.

  8. Pharmaceutical and physical properties of paclitaxel (Taxol) complexes with cyclodextrins.

    PubMed

    Sharma, U S; Balasubramanian, S V; Straubinger, R M

    1995-10-01

    Paclitaxel (as Taxol) is under clinical investigation for treatment of a variety of cancers. Because of its low aqueous solubility, paclitaxel is administered in polyethoxylated castor oil (Cremophor EL) and ethanol, a vehicle associated with severe hypersensitivity reactions. Cyclodextrins (CyDs) are molecular complexing agents that can increase the solubility and stability of some poorly soluble drugs and were investigated here as a means to obviate the requirement for Cremophor. A variety of beta- and gamma-cyclodextrins were tested; (hydroxypropyl)-(HP beta CyD), (hydroxyethyl)-(HE beta CyD), and dimethyl-(DM beta CyD) beta CyD increased paclitaxel solubility 2 x 10(3)-fold or more and did not alter the cytostatic properties of paclitaxel in vitro. The quantity of drug solubilized increased with the CyD concentration, but precipitation upon dilution occurred with some CyDs or stoichiometries. Thermal and spectroscopic (fluorescence, IR, NMR, and circular dichroism) analyses provided evidence of complex formation that was stable in the solid state but weak in solution, suggesting an explanation for the observed precipitation upon dilution. DM beta CyD solutions of < or = 3.7 mol % (mole of drug:mole of CyD) showed no precipitation upon dilution, nor did HP beta CyD solutions of < or = 0.14 mol %. Maximum tolerated dose (MTD) experiments showed uncomplexed DM beta CyD to be toxic in mice at doses of 2 g CyD/kg body weight, the quantity required to administer paclitaxel at 10 mg/kg. HP beta CyD allowed paclitaxel administration at higher doses and had an MTD of 25 mg drug/kg. The CyDs tested are marginal in feasibility for paclitaxel administration, and their use in taxane formulation will require a reduction of the dose-limiting toxicity of the CyD itself.

  9. [Creation and evaluation of the respective rank problem solution worksheet for improvement pharmaceutical management quality].

    PubMed

    Tanaka, Masayo; Orii, Takao; Kawai, Noriko; Kondo, Yoshiko

    2002-08-01

    A respective rank problem solution worksheet was developed focusing on problem solution in training in pharmaceutical management. How the training influenced the instructions given to patients was then evaluated in two pharmacists in the NTT East Kanto Medical Center and three in an Ofuna central hospital. After the five pharmacists underwent the training, the records of 10 medication instructions to patients given by each before and after the training were compared. The records were analyzed based on a point calculation table, and the number of acquisition points was computed. The acquisition points increased significantly after training for all five pharmacists, from a mean of 3.56 before training to a mean of 8.34 after training. Although the acquisition points related to patient education were high, those for intervention during therapeutic monitoring, such as for adverse drug reaction or the selection of appropriate pharmaceuticals were acceptable, increasing to a mean 8.4 items after training compared with 4.4 items before. The respective rank problem solution worksheet is therefore considered useful in improving the quality of training pharmaceutical management.

  10. Improving Energy Efficiency in Pharmaceutical ManufacturingOperations -- Part I: Motors, Drives and Compressed Air Systems

    SciTech Connect

    Galitsky, Christina; Chang, Sheng-chien; Worrell, Ernst; Masanet,Eric

    2006-04-01

    In Part I of this two-part series, we focus on efficient use of motors, drives and pumps, both for process equipment and compressed air systems. Pharmaceutical manufacturing plants in the U.S. spend nearly $1 billion each year for the fuel and electricity they need to keep their facilities running (Figure 1, below). That total that can increase dramatically when fuel supplies tighten and oil prices rise, as they did last year. Improving energy efficiency should be a strategic goal for any plant manager or manufacturing professional working in the drug industry today. Not only can energy efficiency reduce overall manufacturing costs, it usually reduces environmental emissions, establishing a strong foundation for a corporate greenhouse-gas-management program. For most pharmaceutical manufacturing plants, Heating, Ventilation and Air Conditioning (HVAC) is typically the largest consumer of energy, as shown in Table 1 below. This two-part series will examine energy use within pharmaceutical facilities, summarize best practices and examine potential savings and return on investment. In this first article, we will focus on efficient use of motors, drives and pumps, both for process equipment and compressed air systems. Part 2, to be published in May, will focus on overall HVAC systems, building management and boilers.

  11. [Rheologic properties of some pharmaceutical excipients in drug forms and cosmetic preparation technology].

    PubMed

    Tsagareishvili, G V; Bashura, A A; Alekseeva, M A; Bashura, G S

    2012-06-01

    The establishment of mechanisms and principles of the formation of deformation (fracture) of spatial structure of bentonite solutions and various solutions and disperse systems is one or the most important problems of modern pharmaceutical technology. The article presents the results of a long-term research of influence of high-molecular compounds and surfactants on the properties of designed dosage drug forms and cosmetic preparation. Research data, as the basis for drug combinations "gel" with dekamitoksin, extract Aesculus hippocastanum L and probiotics. PMID:22859452

  12. Using information technology for an improved pharmaceutical care delivery in developing countries. Study case: Benin.

    PubMed

    Edoh, Thierry Oscar; Teege, Gunnar

    2011-10-01

    One of the problems in health care in developing countries is the bad accessibility of medicine in pharmacies for patients. Since this is mainly due to a lack of organization and information, it should be possible to improve the situation by introducing information and communication technology. However, for several reasons, standard solutions are not applicable here. In this paper, we describe a case study in Benin, a West African developing country. We identify the problem and the existing obstacles for applying standard ECommerce solutions. We develop an adapted system approach and describe a practical test which has shown that the approach has the potential of actually improving the pharmaceutical care delivery. Finally, we consider the security aspects of the system and propose an organizational solution for some specific security problems. PMID:21519942

  13. Using information technology for an improved pharmaceutical care delivery in developing countries. Study case: Benin.

    PubMed

    Edoh, Thierry Oscar; Teege, Gunnar

    2011-10-01

    One of the problems in health care in developing countries is the bad accessibility of medicine in pharmacies for patients. Since this is mainly due to a lack of organization and information, it should be possible to improve the situation by introducing information and communication technology. However, for several reasons, standard solutions are not applicable here. In this paper, we describe a case study in Benin, a West African developing country. We identify the problem and the existing obstacles for applying standard ECommerce solutions. We develop an adapted system approach and describe a practical test which has shown that the approach has the potential of actually improving the pharmaceutical care delivery. Finally, we consider the security aspects of the system and propose an organizational solution for some specific security problems.

  14. [Rising attention to the market to ratio meet demand of improving efficiency of pharmaceutical circulation--based on complicated variety and specification of drugs].

    PubMed

    Chen, Zhaoxing; Sun, Lihua

    2010-05-01

    Analyzing the complicated variety and specification of drugs and the objective demand of pharmaceutical circulation, to seek out the key factors in improving the efficiency of pharmaceutical circulation, for putting forward suggestions to promote the development of pharmaceutical circulation in China. The conclusion is drawed from industrial organization theory and successful experience of foreign countries, high market attention met with the demand of complicated variety and specification of drugs in pharmaceutical circulation.

  15. Micro-mechanical properties of drying material bridges of pharmaceutical excipients.

    PubMed

    Farber, Leon; Tardos, Gabriel I; Michaels, James N

    2005-12-01

    This work is part of a larger research effort to elucidate the properties and morphology of pharmaceutical granules produced by wet-granulation. In this work, we measure forces exerted by the drying interparticle bridges. The bridges were formed from aqueous solutions of common pharmaceutical excipients both non-polymeric (lactose, mannitol) and polymeric (hydroxypropyl cellulose (HPC), hydroxypropyl methylcellulose (HPMC), polyvinylpyrrolidone (povidone) (PVP)). We also study the morphology, microstructure and crystalline structure of solidifying bridges. We find that the solidifying behavior and final properties of bridges differ dramatically, depending on the composition of the solution. Bridges containing only lactose or mannitol tend to expand upon solidification, pushing the ends of the bridge apart; in contrast, pure HPC, HPMC, or PVP bridges tend to contract. Bridges crystallized from solution of the pure non-polymeric excipients are polycrystalline, brittle, and have low strength; bridges from the polymeric excipients are amorphous, strong and tough. When the polymeric and non-polymeric excipients are used together, behavior closer to either one or the other extreme takes place. This depends on the relative amount of polymer in the bridge. It was also found that the different polymers impart different behavior on the bridge. The observed differences in solidification behavior have important implications for granule formation, drying and ultimate bridge and granule properties; these are discussed at some length in the paper. PMID:16274947

  16. Co-Crystals: A Novel Approach to Modify Physicochemical Properties of Active Pharmaceutical Ingredients

    PubMed Central

    Yadav, A. V.; Shete, A. S.; Dabke, A. P.; Kulkarni, P. V.; Sakhare, S. S.

    2009-01-01

    Crystal form can be crucial to the performance of a dosage form. This is especially true for compounds that have intrinsic barriers to drug delivery, such as low aqueous solubility, slow dissolution in gastrointestinal media, low permeability and first-pass metabolism. The nature of the physical form and formulation tends to exhibit the greatest effect on bioavailability parameters of water insoluble compounds that need to be given orally in high doses. An alternative approach available for the enhancement of drug solubility, dissolution and bioavailability is through the application of crystal engineering of co-crystals. The physicochemical properties of the active pharmaceutical ingredients and the bulk material properties can be modified, whilst maintaining the intrinsic activity of the drug molecule. This article covers the advantages of co-crystals over salts, solvates (hydrates), solid dispersions and polymorphs, mechanism of formation of co-crystals, methods of preparation of co-crystals and application of co-crystals to modify physicochemical characteristics of active pharmaceutical ingredients along with the case studies. The intellectual property implications of creating co-crystals are also highly relevant. PMID:20502540

  17. Improving pharmaceutical innovation by building a more comprehensive database on drug development and use.

    PubMed

    Daniel, Gregory W; Cazé, Alexis; Romine, Morgan H; Audibert, Céline; Leff, Jonathan S; McClellan, Mark B

    2015-02-01

    New drugs and biologics have had a tremendous impact on the treatment of many diseases. However, available measures suggest that pharmaceutical innovation has remained relatively flat, despite substantial growth in research and development spending. We review recent literature on pharmaceutical innovation to identify limitations in measuring and assessing innovation, and we describe the framework and collaborative approach we are using to develop more comprehensive, publicly available metrics for innovation. Our research teams at the Brookings Institution and Deerfield Institute are collaborating with experts from multiple areas of drug development and regulatory review to identify and collect comprehensive data elements related to key development and regulatory characteristics for each new molecular entity approved over the past several decades in the United States and the European Union. Subsequent phases of our effort will add data on downstream product use and patient outcomes and will also include drugs that have failed or been abandoned in development. Such a database will enable researchers to better analyze the drivers of drug innovation, trends in the output of new medicines, and the effect of policy efforts designed to improve innovation.

  18. Improving pharmaceutical innovation by building a more comprehensive database on drug development and use.

    PubMed

    Daniel, Gregory W; Cazé, Alexis; Romine, Morgan H; Audibert, Céline; Leff, Jonathan S; McClellan, Mark B

    2015-02-01

    New drugs and biologics have had a tremendous impact on the treatment of many diseases. However, available measures suggest that pharmaceutical innovation has remained relatively flat, despite substantial growth in research and development spending. We review recent literature on pharmaceutical innovation to identify limitations in measuring and assessing innovation, and we describe the framework and collaborative approach we are using to develop more comprehensive, publicly available metrics for innovation. Our research teams at the Brookings Institution and Deerfield Institute are collaborating with experts from multiple areas of drug development and regulatory review to identify and collect comprehensive data elements related to key development and regulatory characteristics for each new molecular entity approved over the past several decades in the United States and the European Union. Subsequent phases of our effort will add data on downstream product use and patient outcomes and will also include drugs that have failed or been abandoned in development. Such a database will enable researchers to better analyze the drivers of drug innovation, trends in the output of new medicines, and the effect of policy efforts designed to improve innovation. PMID:25646113

  19. Trust: Need for an Improved Communication between the Public World and the Pharmaceutical Companies

    PubMed Central

    Heinemann, Lutz

    2009-01-01

    In the industrialized world, the negative image that many people (including politicians) have of pharmaceutical companies not only makes the life for those working in this field more difficult, in a sense it is a road block. Without an improvement in communication between the public world and the pharmaceutical industry, one can foresee this industry steadily becoming a more difficult environment to work in. There is a clear need for knowing more about all the work done inside these companies before a new drug is approved (it is not all about marketing…). That society has no understanding of the ever-increasing costs of new drugs is also related to this lack of understanding of how tricky and cumbersome the process is to take a new idea for treating a certain disease to production of a marketed drug. With a relatively small investment of money, but with an investment of much good will, brain power, and trust, it should be possible to bring all relevant parties together and make a change. PMID:20046667

  20. Non-destructive determination of anisotropic mechanical properties of pharmaceutical solid dosage forms.

    PubMed

    Akseli, I; Hancock, B C; Cetinkaya, C

    2009-07-30

    The mechanical property anisotropy of compacts made from four commercially available pharmaceutical excipient powders (microcrystalline cellulose, lactose monohydrate, ascorbic acid, and aspartame) was evaluated. The speed of pressure (longitudinal) waves in the uni-axially compressed cubic compacts of each excipient in the three principle directions was determined using a contact ultrasonic method. Average Young's moduli of each compact in the axial (x) and radial (y and z) directions were characterized. The contact ultrasonic measurements revealed that average Young's modulus values vary with different testing orientations which indicate Young's modulus anisotropy in the compacts. The extent of Young's modulus anisotropy was quantified by using a dimensionless ratio and was found to be significantly different for each material (microcrystalline cellulose>lactose>aspartame>ascorbic acid). It is also observed that using the presented contact method, compacts at high solid fraction (0.857-0.859) could be differentiated than those at the solid fraction of 0.85 in their groups. The presented contact ultrasonic method is an attractive tool since it has the advantages of being sensitive to solid fraction ratio, non-destructive, requiring small amount of material and rapid. It is noteworthy that, since the approach provides insight into the performance of common pharmaceutical materials and fosters increased process knowledge, it can be applied to broaden the understanding of the effect of the mechanical properties on the performance (e.g., disintegration profiles) of solid oral dosage forms.

  1. Active Pharmaceutical Ingredients: Prediction of Physical-Chemical Properties from First Principles

    NASA Astrophysics Data System (ADS)

    Valenzano, Loredana

    2013-03-01

    Polymorphism in active pharmaceutical ingredients (APIs) plays a crucial role both for medical and intellectual property concerns but despite ongoing efforts, experimental and computational investigations of the existence and the physical-chemical properties of the same compound in different forms is still an open question.While comparison between computed and experimental values for properties derived from differences between states is often promising (such as bulk modulus), results are disappointing for absolute values (such as density). Quantum mechanical computational methods describe the systems at 0K, experimentally properties are often evaluated at room temperature. Therefore it is not surprising that results determined from first principles dramatically differ from those obtained experimentally. By applying a quantum mechanical periodic approach that takes into account long range London dispersion forces fitted for solid materials, and by imposing different cell volumes corresponding to different thermodynamic conditions, we show how results from calculations at 0K (structures, vibrational spectra, elastic constants) may be compared to experimental values at higher temperatures, helping to foster a stronger linkage between computational and experimental work on systems such as APIs. Where experimental results are not available, our work represents an innovative approach in addressing the properties of APIs. Our results can also serve as foundation for the developing of new force fields to be adopted within a multi-scale computational approach.

  2. Significant Improvement in Sleep in People with Intellectual Disabilities Living in Residential Settings by Non-Pharmaceutical Interventions

    ERIC Educational Resources Information Center

    Hylkema, T.; Vlaskamp, C.

    2009-01-01

    Background: Although about 15 to 50 percent of people with intellectual disabilities (ID) living in residential settings suffer from sleep problems, scant attention is paid to these problems. Most available studies focus on pharmaceutical solutions. In this study we focus on improving sleep in people with intellectual disabilities living in…

  3. Improving the Practical Education of Chemical and Pharmaceutical Engineering Majors in Chinese Universities

    ERIC Educational Resources Information Center

    Zhao, Feng-qing; Yu, Yi-feng; Ren, Shao-feng; Liu, Shao-jie; Rong, Xin-yu

    2014-01-01

    Practical education in chemical engineering has drawn increasing attention in recent years. This paper discusses two approaches to teaching and learning about experiments among upper-level chemical and pharmaceutical engineering majors in China. On the basis of years of experience in teaching chemical and pharmaceutical engineering, we propose the…

  4. Deformation properties of pharmaceutical excipients determined using an in-die and out-die method.

    PubMed

    Ilić, Ilija; Govedarica, Biljana; Šibanc, Rok; Dreu, Rok; Srčič, Stane

    2013-03-25

    This study investigated deformation mechanisms of some commonly used pharmaceutical fillers, such as microcrystalline cellulose, lactose, dicalcium phosphate, isomalt and cornstarch, using a combination of the in-die and out-die method with the Heckel and Walker models. The tableting mixtures contained of 98.5% (w/w) filler, the rest consisted of dry binder and an antiadhesive agent. Our results showed that plasticity and elasticity may be considered independent deformation properties as highly plastic materials (microcrystalline cellulose, cornstarch) also exhibited high elasticity. Particular emphasis was placed on explaining the differences observed between the in-die and out-die method-comparison revealed that the differences are a consequence of the material's elastic properties. Larger error of in-die results can be expected for more elastic materials, and thus in-die Heckel should be used with some considerations. In contrast, the Walker model was found to be more robust and smaller differences were observed between the two methods. We consider the most correct results to have been obtained by the out-die approach, which excludes the elastic properties of the material evaluated. An excellent correlation between elastic determination at the single-particle level and multiple-particle scale was demonstrated, suggesting a great potential of nanoscale determination of a material's mechanical properties for better elucidation of deformation mechanisms.

  5. Energy Efficiency Improvement and Cost Saving Opportunities for the Pharmaceutical Industry. An ENERGY STAR Guide for Energy and Plant Managers

    SciTech Connect

    Galitsky, Christina; Galitsky, Christina; Chang, Sheng-chieh; Worrell, Ernst; Masanet, Eric

    2008-03-01

    The U.S. pharmaceutical industry consumes almost $1 billion in energy annually. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. pharmaceutical industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy efficient technologies that can be implemented at the component, process, system, and organizational levels. A discussion of the trends, structure, and energy consumption characteristics of the U.S. pharmaceutical industry is provided along with a description of the major process steps in the pharmaceutical manufacturing process. Expected savings in energy and energy-related costs are given for many energy efficiency measures, based on case study data from real-world applications in pharmaceutical and related facilities worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. The information in this Energy Guide is intended to help energy and plant managers reduce energy consumption in a cost-effective manner while meeting regulatory requirements and maintaining the quality of products manufactured. At individual plants, further research on the economics of the measures?as well as their applicability to different production practices?is needed to assess potential implementation of selected technologies.

  6. The challenge of improved secretory production of active pharmaceutical ingredients in Saccharomyces cerevisiae: a case study on human insulin analogs.

    PubMed

    Kazemi Seresht, Ali; Palmqvist, Eva A; Schluckebier, Gerd; Pettersson, Ingrid; Olsson, Lisbeth

    2013-10-01

    The yeast Saccharomyces cerevisiae has widely been used as a host for the production of heterologous proteins. Great attention has been put on improved secretory production of active pharmaceutical ingredients, and the secretory pathway of this eukaryotic host has been the playground of diverse strain engineering studies, aiming at enhanced cellular capacities for folding and trafficking of the target proteins. However, the cellular quality assessment for secretory proteins remains mostly unpredictable, and different target proteins often do not picture similar secretion yields, underlining the dependency of efficient secretion on the physicochemical properties of the protein of interest. In this study, two human insulin analog precursors (IAPs) with minor differences in their amino acid sequences were used as model secretory proteins. No differences between cells expressing these two proteins were found in the IAP transcript levels, gene copy numbers, or intra-cellularly accumulated proteins, yet a more than sevenfold difference in their secretion yields was found. Physiological characterization of cells expressing these proteins in batch processes revealed no significant difference in their specific growth rate, but an altered overflow metabolism. Global transcriptome analysis carried out in chemostat experiments pinpointed distinct steps during the protein maturation pathway to be differentially regulated and indicated an increased degradation of the IAP with the low secretion yield. In silico protein structure modeling of the IAPs suggested a difference in conformational stability, induced by the amino acid substitution, which most likely resulted in disparity in trafficking through the secretory pathway and thus a large difference in secretion yields. PMID:23592021

  7. Cyclodextrins in pharmaceutical formulations I: structure and physicochemical properties, formation of complexes, and types of complex.

    PubMed

    Jambhekar, Sunil S; Breen, Philip

    2016-02-01

    Cyclodextrins are cyclic oligosaccharides that have been recognized as pharmaceutical adjuvants for the past 20 years. The molecular structure of these glucose derivatives, which approximates a truncated cone, bucket, or torus, generates a hydrophilic exterior surface and a nonpolar interior cavity. Cyclodextrins can interact with appropriately sized drug molecules to yield an inclusion complex. These noncovalent inclusion complexes offer a variety of advantages over the noncomplexed form of a drug. Cyclodextrins are primarily used to enhance the aqueous solubility, physical chemical stability, and bioavailability of drugs. Their other applications include preventing drug-drug interactions, converting liquid drugs into microcrystalline powders, minimizing gastrointestinal and ocular irritation, and reducing or eliminating unpleasant taste and smell. Here, we discuss the physical chemical properties of various cyclodextrins, including the effects of substitutions on these properties. Additionally, we report on the regulatory status of their use, commercial products containing cyclodextrins, toxicological considerations, and the forces involved in complex formation. We also highlight the types of complex formed and discuss the methods used to determine the types of complex present. PMID:26686054

  8. Dielectric properties of pharmaceutical materials relevant to microwave processing: effects of field frequency, material density, and moisture content.

    PubMed

    Heng, Paul W S; Loh, Z H; Liew, Celine V; Lee, C C

    2010-02-01

    The rising popularity of microwaves for drying, material processing and quality sensing has fuelled the need for knowledge concerning dielectric properties of common pharmaceutical materials. This article represents one of the few reports on the density and moisture content dependence of the dielectric properties of primary pharmaceutical materials and their relevance to microwave-assisted processing. Dielectric constants (epsilon') and losses (epsilon'') of 13 pharmaceutical materials were measured over a frequency range of 1 MHz-1 GHz at 23 +/- 1 degrees C using a parallel-electrode measurement system. Effects of field frequency, material density and moisture content on dielectric properties were studied. Material dielectric properties varied considerably with frequency. At microwave frequencies, linear relationships were established between cube-root functions of the dielectric parameters [symbols: see text] and density which enabled dielectric properties of materials at various densities to be estimated by regression. Moisture content was the main factor that contributed to the disparities in dielectric properties and heating capabilities of the materials in a laboratory microwave oven. The effectiveness of a single frequency density-independent dielectric function for moisture sensing applications was explored and found to be suitable within low ranges of moisture contents for a model material.

  9. Patent and intellectual property rights related to pharmaceuticals: global future perspectives: Japan.

    PubMed

    Komatani, Takeshi S

    2016-07-01

    The Japanese patent system is reviewed and summarized from pharmaceutical industrial point of view. Current systems and practice are introduced and current problems in pharma patent are discussed, and perspective for future patent system in the field of pharmaceutical industry is discussed and proposed.

  10. Patent and intellectual property rights related to pharmaceuticals: global future perspectives: Japan.

    PubMed

    Komatani, Takeshi S

    2016-07-01

    The Japanese patent system is reviewed and summarized from pharmaceutical industrial point of view. Current systems and practice are introduced and current problems in pharma patent are discussed, and perspective for future patent system in the field of pharmaceutical industry is discussed and proposed. PMID:27334256

  11. The Chinese pharmaceutical market at the crossroads: pro-competition solutions to improve access, quality and affordability.

    PubMed

    Wang, Y Richard

    2005-01-01

    The Chinese pharmaceutical market is large in absolute size (the second largest in Asia), but it faces similar problems to those that plague other developing countries, such as a lack of adequate patent protection, low pharmaceutical spending per capita, but high pharmaceutical expenditure as a proportion of total medical spending, and a lack of health insurance coverage. In this article, the pros and cons of two pro-competition policy proposals for China are explored. The first proposal is to follow the E5 guideline of the International Conference on Harmonisation and waive unnecessary local clinical trials for global new drugs that have been approved by the US Food and Drug Administration or the European Medicines Agency (except for drugs for which there is a real possibility of there being ethnic differences in patient responses). The second proposal is to tighten the standards for generic drugs and approve only bioequivalent ones. While the first proposal encourages price competition between similar compounds in the same therapeutic class, the second proposal enhances generic competition for off-patent drugs. Working together, these two proposals would improve access to and the quality and affordability of pharmaceuticals in China.

  12. Multivariate analysis in the pharmaceutical industry: enabling process understanding and improvement in the PAT and QbD era.

    PubMed

    Ferreira, Ana P; Tobyn, Mike

    2015-01-01

    In the pharmaceutical industry, chemometrics is rapidly establishing itself as a tool that can be used at every step of product development and beyond: from early development to commercialization. This set of multivariate analysis methods allows the extraction of information contained in large, complex data sets thus contributing to increase product and process understanding which is at the core of the Food and Drug Administration's Process Analytical Tools (PAT) Guidance for Industry and the International Conference on Harmonisation's Pharmaceutical Development guideline (Q8). This review is aimed at providing pharmaceutical industry professionals an introduction to multivariate analysis and how it is being adopted and implemented by companies in the transition from "quality-by-testing" to "quality-by-design". It starts with an introduction to multivariate analysis and the two methods most commonly used: principal component analysis and partial least squares regression, their advantages, common pitfalls and requirements for their effective use. That is followed with an overview of the diverse areas of application of multivariate analysis in the pharmaceutical industry: from the development of real-time analytical methods to definition of the design space and control strategy, from formulation optimization during development to the application of quality-by-design principles to improve manufacture of existing commercial products.

  13. 30 years of pharmaceutical cost-utility analyses: growth, diversity and methodological improvement.

    PubMed

    Neumann, Peter J; Fang, Chi-Hui; Cohen, Joshua T

    2009-01-01

    To review and critically evaluate published cost-utility analyses (CUAs) pertaining to pharmaceuticals for the past 3 decades. We examined data from the Tufts Medical Center Cost-Effectiveness Analysis Registry (www.cearegistry.org), which contains detailed information on English-language CUAs and their ratios (in $US, year 2008 values) published in peer-reviewed journals. We summarized study features using descriptive statistics for articles published from 1976 to 2006. Changes in study methodology over time were analysed by trend test. Analysis of ratios was restricted to those published from 2000 to 2006 from studies that correctly discounted future costs and benefits. Factors associated with having a favourable value (defined to be more than the median for all included ratios) were identified by logistic regression. Of 1393 CUAs published through 2006, 640 (45.9%) pertained to pharmaceuticals. The proportion of CUAs that focussed on pharmaceuticals increased from 34% for the period 1990-5 to 47% for the period 2001-5. Investigations with a US perspective accounted for 51% of all CUAs, although this proportion has decreased over time. The UK perspective investigations accounted for nearly 16% of all studies, and this portion has increased over time. About 24% of all CUAs were sponsored by industry, 48% were sponsored by non-industry sources, and 28% did not disclose their funding. Adherence to good methodological practices is roughly similar for studies with industry and non-industry sponsorship. Adherence to these practices has increased over time. Among the 1969 ratios meeting our inclusion criteria, the median value was $US22 000 per QALY. Logistic regression revealed that, while controlling for the intervention category (e.g. pharmaceutical, medical device, screening), ratios were more likely to be favourable if they were from studies sponsored by a pharmaceutical or device manufacturer (OR 1.53; 95% CI 1.07, 2.19). Ratios for pharmaceutical CUAs were less

  14. Understanding solid-state properties of triglycerides used in pharmaceutical and food microencapsulation.

    PubMed

    Elviri, Lisa; Mangia, Mattia; Menabeni, Roberta; Della Bella, Andrea; Camellini, Claudia; Beltrami, Diego; Arduini, Lauro; Bettini, Ruggero

    2015-01-01

    Hydrophobic materials, in particular hydrogenated vegetable oils, HVO, are extensively used as coating materials in food and pharmaceutical systems. Correct application of these coatings requires an evaluation of their behaviour as a function of various parameters such as melting temperature, solubility, concentration and/or pH. The purpose of this study was to assess the physico-chemical properties of an HVO in terms of composition, crystallisation, phase transition and polymorphism using a variety of analytical techniques, such as electrospray mass spectrometry (ESI-MS), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). High-resolution ESI-MS allowed establishment of the HVO main composition of long-chain triglycerides (average molecular weight 1183 Da). DSC results showed that thermal history determines the formation of at least two polymorphs of HVO, namely two different crystal forms, assigned as form α, melting point (m.p.) 48 °C, and form β', m.p. 60 °C. A third polymorph, the more thermodynamically stable β-form, having a melting point at 62 °C, is obtained by solution-mediated re-crystallisation. Phase transformation paths were investigated by isothermal DSC experiments, which evidenced that the α-form is kinetically stable at temperatures lower than 25 °C. These data are of particular interest in practical applications such as spray freezing or pan coating where significant heat transfer phenomena are involved.

  15. Comparison of pharmaceutical properties of topical non-steroidal anti-inflammatory drug preparations on quality of life.

    PubMed

    Shibata, Yuuka; Ikeda, Hiroaki; Kondou, Yoshihiro; Kihira, Kenji

    2005-05-01

    To compare the effects of different pharmaceutical properties of commercially available topical nonsteroidal antiinflammatory drugs (NSAIDs) on the quality of life, we administered a questionnaire to 65 healthy volunteers. We investigated five creams, five gels, and four solutions of topical NSAID preparations in this study. The survey was conducted to clarify the relationship of their answers and pharmaceutical properties of the topical NSAID preparations. Questions addressed spreadability, smell, viscosity, and comfort level of the topical NSAID preparations. Among the five creams, Napageln had lower spreadability, less smell, and greater viscosity than the other preparations. Because of its easy spreadability, weak smell, and low viscosity, the volunteers favored Sector cream among the cream preparations. Among the five gel preparations, Inteban had less spreadability, stronger smell, and higher viscosity than the other preparations. The volunteers favored Epatec over the other gel preparations. All four solutions had the odor of menthol and other artificial ingredients, except for Napageln. These findings indicate that information on the pharmaceutical properties of commercially available topical NSAID preparations will be helpful to physicians and pharmacists in conducting medical treatment and prescribing.

  16. Physicochemical and Antimicrobial Properties of Cocoa Pod Husk Pectin Intended as a Versatile Pharmaceutical Excipient and Nutraceutical.

    PubMed

    Adi-Dako, Ofosua; Ofori-Kwakye, Kwabena; Frimpong Manso, Samuel; Boakye-Gyasi, Mariam El; Sasu, Clement; Pobee, Mike

    2016-01-01

    The physicochemical and antimicrobial properties of cocoa pod husk (CPH) pectin intended as a versatile pharmaceutical excipient and nutraceutical were studied. Properties investigated include pH, moisture content, ash values, swelling index, viscosity, degree of esterification (DE), flow properties, SEM, FTIR, NMR, and elemental content. Antimicrobial screening and determination of MICs against test microorganisms were undertaken using agar diffusion and broth dilution methods, respectively. CPH pectin had a DE of 26.8% and exhibited good physicochemical properties. Pectin had good microbiological quality and exhibited pseudoplastic, shear thinning behaviour, and high swelling capacity in aqueous media. The DE, FTIR, and NMR results were similar to those of previous studies and supported highly acetylated low methoxy pectin. CPH pectin was found to be a rich source of minerals and has potential as a nutraceutical. Pectin showed dose-dependent moderate activity against gram positive and gram negative microorganisms but weak activity against Listeria spp. and A. niger. The MICs of pectin ranged from 0.5 to 4.0 mg/mL, with the highest activity against E. coli and S. aureus (MIC: 0.5-1.0 mg/mL) and the lowest activity against A. niger (MIC: 2.0-4.0 mg/mL). The study has demonstrated that CPH pectin possesses the requisite properties for use as a nutraceutical and functional pharmaceutical excipient. PMID:27066294

  17. Physicochemical and Antimicrobial Properties of Cocoa Pod Husk Pectin Intended as a Versatile Pharmaceutical Excipient and Nutraceutical

    PubMed Central

    Adi-Dako, Ofosua; Frimpong Manso, Samuel; Boakye-Gyasi, Mariam EL; Sasu, Clement; Pobee, Mike

    2016-01-01

    The physicochemical and antimicrobial properties of cocoa pod husk (CPH) pectin intended as a versatile pharmaceutical excipient and nutraceutical were studied. Properties investigated include pH, moisture content, ash values, swelling index, viscosity, degree of esterification (DE), flow properties, SEM, FTIR, NMR, and elemental content. Antimicrobial screening and determination of MICs against test microorganisms were undertaken using agar diffusion and broth dilution methods, respectively. CPH pectin had a DE of 26.8% and exhibited good physicochemical properties. Pectin had good microbiological quality and exhibited pseudoplastic, shear thinning behaviour, and high swelling capacity in aqueous media. The DE, FTIR, and NMR results were similar to those of previous studies and supported highly acetylated low methoxy pectin. CPH pectin was found to be a rich source of minerals and has potential as a nutraceutical. Pectin showed dose-dependent moderate activity against gram positive and gram negative microorganisms but weak activity against Listeria spp. and A. niger. The MICs of pectin ranged from 0.5 to 4.0 mg/mL, with the highest activity against E. coli and S. aureus (MIC: 0.5–1.0 mg/mL) and the lowest activity against A. niger (MIC: 2.0–4.0 mg/mL). The study has demonstrated that CPH pectin possesses the requisite properties for use as a nutraceutical and functional pharmaceutical excipient. PMID:27066294

  18. Comparison of solute-binding properties of plastic materials used as pharmaceutical product containers.

    PubMed

    Jenke, Dennis; Couch, Tom; Gillum, Amy

    2010-01-01

    Material/water equilibrium binding constants (E(b)) were determined for 11 organic solutes and 2 plastic materials commonly used in pharmaceutical product containers (plasticized polyvinyl chloride and polyolefin). In general, solute binding by the plasticized polyvinyl chloride material was greater, by nearly an order of magnitude, than the binding by the polyolefin (on an equal weight basis). The utilization of the binding constants to facilitate container compatibility assessments (e.g., drug loss by container binding) for drug-containing products is discussed.

  19. Pharmacological Properties and Therapeutic Potential of Naringenin: A Citrus Flavonoid of Pharmaceutical Promise.

    PubMed

    Rani, Neha; Bharti, Saurabh; Krishnamurthy, Bhaskar; Bhatia, Jagriti; Sharma, Charu; Kamal, Mohammad Amjad; Ojha, Shreesh; Arya, Dharamvir Singh

    2016-01-01

    Naringenin chemically known as 5,7-dihydroxy-2-(4-hydroxyphenyl)chroman-4-one is a common dietary polyphenolic constituent of the citrus fruits. It has received considerable attention for pharmaceutical and nutritional development due to potent pharmacological activities and therapeutic potential. Accruing evidence from both in vitro and in vivo studies have unraveled numerous biological targets along with complex underlying mechanisms suggesting possible therapeutic applications of naringenin in various neurological, cardiovascular, gastrointestinal, rheumatological, metabolic and malignant disorders. Functionally, this ameliorative effect of naringenin is primarily attributed to its antiinflammatory (via inhibiting recruitment of cytokines and inflammatory transcription factors) and anti-oxidant (via scavenging of free radicals, bolstering of endogenous antioxidant defense system and metal ion chelation) effects. The present article provides a comprehensive review of the various studies that have evaluated the therapeutic potential of naringenin and its actions at the molecular level. It also summarizes the pharmacokinetic data and issues and challenges involved in pharmaceutical development and suggest that it may be a potential agent for further exploration as well as may be useful as a dietary adjunct in treatment of various human ailments.

  20. Removal of caffeine from pharmaceutical wastewater by adsorption: influence of NOM, textural and chemical properties of the adsorbent.

    PubMed

    Álvarez-Torrellas, Silvia; Rodríguez, Araceli; Ovejero, Gabriel; Gómez, José María; García, Juan

    2016-01-01

    This work involves the study of the influence of textural and chemical adsorbent properties on natural organic matter (NOM) removal and the simultaneous adsorption of caffeine and NOM in pharmaceutical wastewater. The performance of a microporous activated carbon, Calgon F400, a synthesized mesoporous carbon from peach stones and a commercial sepiolite in the removal of NOM of a WWTP effluent, and the competitive adsorption of caffeine/NOM were evaluated. It was evidenced that the microporous structure of the adsorbents significantly conditioned the removal of NOM, finding that F400 activated carbon (microporous volume of 0.46 cm(3) g(-1)) led to a NOM removal of 45%. The presence of NOM in the aqueous medium led to worse adsorption parameters, including adsorption capacity at breakthrough time, mass transfer zone length and fractional bed utilization. Additionally, an overshooting in the Total Organic Carbon concentration (TOC/TOC0 = 1.05) was observed in the sepiolite adsorption fixed-bed experiment, due to the displacement of the background NOM. The tested adsorbents were efficient in the removal of caffeine from a pharmaceutical wastewater, finding a competitive effect between the target compound and the background NOM for the active sites. PMID:26593681

  1. Removal of caffeine from pharmaceutical wastewater by adsorption: influence of NOM, textural and chemical properties of the adsorbent.

    PubMed

    Álvarez-Torrellas, Silvia; Rodríguez, Araceli; Ovejero, Gabriel; Gómez, José María; García, Juan

    2016-01-01

    This work involves the study of the influence of textural and chemical adsorbent properties on natural organic matter (NOM) removal and the simultaneous adsorption of caffeine and NOM in pharmaceutical wastewater. The performance of a microporous activated carbon, Calgon F400, a synthesized mesoporous carbon from peach stones and a commercial sepiolite in the removal of NOM of a WWTP effluent, and the competitive adsorption of caffeine/NOM were evaluated. It was evidenced that the microporous structure of the adsorbents significantly conditioned the removal of NOM, finding that F400 activated carbon (microporous volume of 0.46 cm(3) g(-1)) led to a NOM removal of 45%. The presence of NOM in the aqueous medium led to worse adsorption parameters, including adsorption capacity at breakthrough time, mass transfer zone length and fractional bed utilization. Additionally, an overshooting in the Total Organic Carbon concentration (TOC/TOC0 = 1.05) was observed in the sepiolite adsorption fixed-bed experiment, due to the displacement of the background NOM. The tested adsorbents were efficient in the removal of caffeine from a pharmaceutical wastewater, finding a competitive effect between the target compound and the background NOM for the active sites.

  2. PICA Variants with Improved Mechanical Properties

    NASA Technical Reports Server (NTRS)

    Thornton, Jeremy; Ghandehari, Ehson M.; Fan, Wenhong; Stackpoole, Margaret; Chavez-Garcia, Jose

    2011-01-01

    Phenolic Impregnated Carbon Ablator (PICA) is a member of the family of Lightweight Ceramic Ablators (LCAs) and was developed at NASA Ames Research Center as a thermal protection system (TPS) material for the Stardust mission probe that entered the Earth s atmosphere faster than any other probe or vehicle to date. PICA, carbon fiberform base and phenolic polymer, shows excellent thermal insulative properties at heating rates from about 250 W/sq cm to 1000 W/sq cm. The density of standard PICA - 0.26 g/cu cm to 0.28 g/cu cm - can be changed by changing the concentration of the phenolic resin. By adding polymers to the phenolic resin before curing it is possible to significantly improve the mechanical properties of PICA without significantly increasing the density.

  3. Improving near-infrared prediction model robustness with support vector machine regression: a pharmaceutical tablet assay example.

    PubMed

    Igne, Benoît; Drennen, James K; Anderson, Carl A

    2014-01-01

    Changes in raw materials and process wear and tear can have significant effects on the prediction error of near-infrared calibration models. When the variability that is present during routine manufacturing is not included in the calibration, test, and validation sets, the long-term performance and robustness of the model will be limited. Nonlinearity is a major source of interference. In near-infrared spectroscopy, nonlinearity can arise from light path-length differences that can come from differences in particle size or density. The usefulness of support vector machine (SVM) regression to handle nonlinearity and improve the robustness of calibration models in scenarios where the calibration set did not include all the variability present in test was evaluated. Compared to partial least squares (PLS) regression, SVM regression was less affected by physical (particle size) and chemical (moisture) differences. The linearity of the SVM predicted values was also improved. Nevertheless, although visualization and interpretation tools have been developed to enhance the usability of SVM-based methods, work is yet to be done to provide chemometricians in the pharmaceutical industry with a regression method that can supplement PLS-based methods. PMID:25358108

  4. Modeling of the solution interaction properties of plastic materials used in pharmaceutical product container systems.

    PubMed

    Jenke, Dennis; Couch, Tom; Gillum, Amy; Sadain, Salma

    2009-01-01

    Material/water equilibrium binding constants (Eb) were determined for 14 organic solutes and 17 plastic raw materials that could be used in pharmaceutical product container systems. Correlations between the measured binding constants and the organic solute's octanol/water and hexane/water partition coefficients were obtained. In general, while the materials examined exhibited a wide range of binding characteristics, the tested materials by and large fell within two broad classes: (1) those that were octanol-like in their binding characteristics, and (2) those that were hexane-like. Materials of the same class (e.g., polypropylenes) generally had binding models that were very similar. Rank ordering of the materials in terms of their magnitude of drug binding (least binding to most binding) was as follows: polypropylene < polyethylene < polyamide < styrene-ethylene-butylene-styrene < copolyester ether elastomer approximately equal to amine-terminated poly fatty acid amide polymer. The utilization of the developed models to estimate drug loss via sorption by the container is discussed.

  5. First report about pharmaceutical properties and phytochemicals analysis of Rosa abyssinica R. Br. ex Lindl. (Rosaceae).

    PubMed

    Moustafa, Mahmoud Fawzy; Alrumman, Sulaiman Abdullah

    2015-11-01

    In vitro antimicrobial efficacy of seven solvent extracts from leaves and hips of Saudi Arabian weed Rosa abyssinica against a variety of human pathogenic bacteria and Candida species have been evaluated using well diffusion methods. Phytochemicals present in the leaves and hips of Rosa abyssinica has been characterized using Gas Chromatogram Mass spectrometry analysis. The extracts comparative efficacy against tested microbes gained from the fresh and dry leaves exhibited more prominent activity than fresh and dry hips. The methanol, chloroform, petroleum ether, acetone and diethyl ether extracts have a greater lethal effect on pathogenic microbes than hot water extracts, while cold-water extracts showed no activity. Twenty-four phytochemicals have been characterized from ethanol extract of the leaves of Rosa abyssinica and fifteen from hips by GC-MS. The major compounds detected in the leaves were squalene (38.21%), ethane, 1,1-diethoxy- (9.65%), β-D-glucopyranose, 1,6-anhydro- (8.55%), furfural (5.50%) and 2-furancarboxaldehyde 5-(hydroxymethyl)- (5.19%). The major compounds in the hips were 2-furancarboxaldehyde 5-(hydroxymethyl)- (51.27%), β-D-glucopyranose, 1,6-anhydro- (8.18%), 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl- (7.42%), 2,5-furandione, dihydro-3-methylene- (6.79%) and furfural (5.99%). Current findings indicate that extract from leaves and hips of Rosa abyssinica and the bioactive components present could be used as pharmaceutical agents.

  6. Towards a new method of assessing the antithrombotic properties of pharmaceutical compounds.

    PubMed

    Hartley, R W

    1992-01-01

    This paper describes the initial development of a novel technique which, following further work, may prove suitable for the in vivo screening of pharmaceutical compounds for evidence of antithrombotic activity. Its inception is shown to be a consequence of an amalgamation of those ultrasonic methods associated with the clinical detection of occlusions and laser Doppler velocimetry. Both topics are discussed and then brought together through a concept whereby the efficacy of compounds might be evaluated in animal models by measuring the velocity of blood in the fluid jet formed distal to an induced thrombus. In accord with the evolved measurement rationale there then follows a description of a laser Doppler microscope, an analyser for extracting the required velocity information from the Doppler shift spectrum and a series of experiments using a thrombus analogue in a narrow-bore glass flow tube. Finally, the results from one in vivo experiment are presented. Speculation about how the method might be developed further is contained within the discussion. PMID:1533255

  7. Lorentz contact resonance spectroscopy for nanoscale characterisation of structural and mechanical properties of biological, dental and pharmaceutical materials.

    PubMed

    Khanal, Dipesh; Dillon, Eoghan; Hau, Herman; Fu, Dong; Ramzan, Iqbal; Chrzanowski, Wojciech

    2015-12-01

    Scanning probe microscopy has been widely used to obtain topographical information and to quantify nanostructural properties of different materials. Qualitative and quantitative imaging is of particular interest to study material-material interactions and map surface properties on a nanoscale (i.e. stiffness and viscoelastic properties). These data are essential for the development of new biomedical materials. Currently, there are limited options to map viscoelastic properties of materials at nanoscale and at high resolutions. Lorentz contact resonance (LCR) is an emerging technique, which allows mapping viscoelasticity of samples with stiffness ranging from a few hundred Pa up to several GPa. Here we demonstrate the applicability of LCR to probe and map the viscoelasticity and stiffness of 'soft' (biological sample: cell treated with nanodiamond), 'medium hard' (pharmaceutical sample: pMDI canister) and 'hard' (human teeth enamel) specimens. The results allowed the identification of nanodiamond on the cells and the qualitative assessment of its distribution based on its nanomechanical properties. It also enabled mapping of the mechanical properties of the cell to demonstrate variability of these characteristics in a single cell. Qualitative imaging of an enamel sample demonstrated variations of stiffness across the specimen and precise identification of enamel prisms (higher stiffness) and enamel interrods (lower stiffness). Similarly, mapping of the pMDI canister wall showed that drug particles were adsorbed to the wall. These particles showed differences in stiffness at nanoscale, which suggested variations in surface composition-multiphasic material. LCR technique emerges as a valuable tool for probing viscoelasticity of samples of varying stiffness's. PMID:26518012

  8. Lorentz contact resonance spectroscopy for nanoscale characterisation of structural and mechanical properties of biological, dental and pharmaceutical materials.

    PubMed

    Khanal, Dipesh; Dillon, Eoghan; Hau, Herman; Fu, Dong; Ramzan, Iqbal; Chrzanowski, Wojciech

    2015-12-01

    Scanning probe microscopy has been widely used to obtain topographical information and to quantify nanostructural properties of different materials. Qualitative and quantitative imaging is of particular interest to study material-material interactions and map surface properties on a nanoscale (i.e. stiffness and viscoelastic properties). These data are essential for the development of new biomedical materials. Currently, there are limited options to map viscoelastic properties of materials at nanoscale and at high resolutions. Lorentz contact resonance (LCR) is an emerging technique, which allows mapping viscoelasticity of samples with stiffness ranging from a few hundred Pa up to several GPa. Here we demonstrate the applicability of LCR to probe and map the viscoelasticity and stiffness of 'soft' (biological sample: cell treated with nanodiamond), 'medium hard' (pharmaceutical sample: pMDI canister) and 'hard' (human teeth enamel) specimens. The results allowed the identification of nanodiamond on the cells and the qualitative assessment of its distribution based on its nanomechanical properties. It also enabled mapping of the mechanical properties of the cell to demonstrate variability of these characteristics in a single cell. Qualitative imaging of an enamel sample demonstrated variations of stiffness across the specimen and precise identification of enamel prisms (higher stiffness) and enamel interrods (lower stiffness). Similarly, mapping of the pMDI canister wall showed that drug particles were adsorbed to the wall. These particles showed differences in stiffness at nanoscale, which suggested variations in surface composition-multiphasic material. LCR technique emerges as a valuable tool for probing viscoelasticity of samples of varying stiffness's.

  9. Ovation Pharmaceuticals, Inc.

    PubMed

    Deutsch, Barry

    2002-11-01

    Ovation Pharmaceuticals, Inc. is a privately held specialty pharmaceutical company that focuses on products in central nervous system (CNS) disorders, oncology and other therapeutic areas where a small number of specialized physicians treat patients. Ovation serves unmet medical needs by acquiring underpromoted branded pharmaceutical products and promising late-stage development products no longer being actively promoted or developed by larger companies. Ovation supports acquired products through active sales and marketing activities and a clinical development program focused on new formulations, new indications and other product improvements. In April 2002, Ovation received a US$150 million commitment in private equity financing, believed to be the largest private equity investment received to date by an early-stage specialty pharmaceutical firm. Ovation used a portion of those funds to purchase its first two products from a major pharmaceutical company in August 2002.

  10. Comprehensive summary--Predict-IV: A systems toxicology approach to improve pharmaceutical drug safety testing.

    PubMed

    Mueller, Stefan O; Dekant, Wolfgang; Jennings, Paul; Testai, Emanuela; Bois, Frederic

    2015-12-25

    This special issue of Toxicology in Vitro is dedicated to disseminating the results of the EU-funded collaborative project "Profiling the toxicity of new drugs: a non animal-based approach integrating toxicodynamics and biokinetics" (Predict-IV; Grant 202222). The project's overall aim was to develop strategies to improve the assessment of drug safety in the early stage of development and late discovery phase, by an intelligent combination of non animal-based test systems, cell biology, mechanistic toxicology and in silico modeling, in a rapid and cost effective manner. This overview introduces the scope and overall achievements of Predict-IV. PMID:25450741

  11. Comprehensive summary--Predict-IV: A systems toxicology approach to improve pharmaceutical drug safety testing.

    PubMed

    Mueller, Stefan O; Dekant, Wolfgang; Jennings, Paul; Testai, Emanuela; Bois, Frederic

    2015-12-25

    This special issue of Toxicology in Vitro is dedicated to disseminating the results of the EU-funded collaborative project "Profiling the toxicity of new drugs: a non animal-based approach integrating toxicodynamics and biokinetics" (Predict-IV; Grant 202222). The project's overall aim was to develop strategies to improve the assessment of drug safety in the early stage of development and late discovery phase, by an intelligent combination of non animal-based test systems, cell biology, mechanistic toxicology and in silico modeling, in a rapid and cost effective manner. This overview introduces the scope and overall achievements of Predict-IV.

  12. Improving Pharmaceutical Aerosol Delivery During Noninvasive Ventilation: Effects of Streamlined Components

    PubMed Central

    Longest, P. Worth; Golshahi, Laleh; Hindle, Michael

    2013-01-01

    Aerosol delivery efficiency during noninvasive ventilation (NIV) is known to be low (~10%) and is associated with poor outcomes of aerosol therapy. The objective of this study was to demonstrate the benefit of redesigning ventilation circuit components using a streamlining approach to improve aerosol delivery during nasal high flow therapy in adults with a conventional-sized aerosol from a mesh nebulizer. The ventilation circuit consisted of a humidifier, mesh nebulizer, mixing T-connector (with 90° angle), 10 mm tubing, and nasal cannula interface. In vitro experiments and computational fluid dynamics analyses were used to evaluate depositional losses in a system of existing components and a newly proposed streamlined T-connector and cannula at flow rates of 30 and 45 LPM. Streamlined designs reduced deposition in the T-connector by a factor of 4. In the nasal cannula, the streamlined designs reduced depositional losses by factors of 1.25–2.0. With the streamlined designs, the highest emitted dose achieved was >40% for a conventional-sized aerosol at 30 LPM. Streamlined geometries offer an effective method to significantly improve the delivery of aerosols through components of NIV systems. This increase in delivery efficiency is important for new inhaled medications with narrow therapeutic windows, increased costs, or long delivery times. PMID:23423706

  13. First report about pharmaceutical properties and phytochemicals analysis of Rosa abyssinica R. Br. ex Lindl. (Rosaceae).

    PubMed

    Moustafa, Mahmoud Fawzy; Alrumman, Sulaiman Abdullah

    2015-11-01

    In vitro antimicrobial efficacy of seven solvent extracts from leaves and hips of Saudi Arabian weed Rosa abyssinica against a variety of human pathogenic bacteria and Candida species have been evaluated using well diffusion methods. Phytochemicals present in the leaves and hips of Rosa abyssinica has been characterized using Gas Chromatogram Mass spectrometry analysis. The extracts comparative efficacy against tested microbes gained from the fresh and dry leaves exhibited more prominent activity than fresh and dry hips. The methanol, chloroform, petroleum ether, acetone and diethyl ether extracts have a greater lethal effect on pathogenic microbes than hot water extracts, while cold-water extracts showed no activity. Twenty-four phytochemicals have been characterized from ethanol extract of the leaves of Rosa abyssinica and fifteen from hips by GC-MS. The major compounds detected in the leaves were squalene (38.21%), ethane, 1,1-diethoxy- (9.65%), β-D-glucopyranose, 1,6-anhydro- (8.55%), furfural (5.50%) and 2-furancarboxaldehyde 5-(hydroxymethyl)- (5.19%). The major compounds in the hips were 2-furancarboxaldehyde 5-(hydroxymethyl)- (51.27%), β-D-glucopyranose, 1,6-anhydro- (8.18%), 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl- (7.42%), 2,5-furandione, dihydro-3-methylene- (6.79%) and furfural (5.99%). Current findings indicate that extract from leaves and hips of Rosa abyssinica and the bioactive components present could be used as pharmaceutical agents. PMID:26639478

  14. Abuse-deterrent formulations: transitioning the pharmaceutical market to improve public health and safety

    PubMed Central

    Worthy, Stacey L.; Barnes, Michael C.; Tarbell, Benjamin

    2015-01-01

    This article evaluates abuse-deterrent formulations (ADFs) as a method to reduce prescription drug abuse while ensuring access to vital medications for individuals with legitimate need; assesses the pros and cons of ADFs and the current state of ADF adoption in the market; and develops policy recommendations to transition the market to ADFs. Although abuse-deterrent technology is still in its nascent stages, ADFs have been proven to reduce prescription drug abuse and its consequences, and even an incremental reduction in abuse can have a significant impact on the nation by reducing the costly social, physical, mental, and public health problems resulting from abuse. Federal ADF policy does not reflect the urgency of the prescription drug abuse epidemic and does not go far enough toward changing the status quo. Policies must be implemented to encourage innovation and a market shift toward ADFs by ensuring any generic medication that references a branded ADF demonstrates that it does not have abuse-deterrent properties inferior to the branded ADF product. Policies must also require federal prescription drug benefit plans to cover ADFs to ensure consumers have access to such medications. PMID:25922655

  15. Improvement in Flavonoids and Phenolic Acids Production and Pharmaceutical Quality of Sweet Basil (Ocimum basilicum L.) by Ultraviolet-B Irradiation.

    PubMed

    Ghasemzadeh, Ali; Ashkani, Sadegh; Baghdadi, Ali; Pazoki, Alireza; Jaafar, Hawa Z E; Rahmat, Asmah

    2016-09-09

    -B treated leaves presented the highest DPPH activity and antiproliferative activity with a half-maximal inhibitory concentration (IC50) value of 56.0 and 40.8 µg/mL, respectively, over that of the control plants (78.0 and 58.2 µg/mL, respectively). These observations suggest that post-harvest irradiation with UV-B can be considered a promising technique to improve the healthy-nutritional and pharmaceutical properties of sweet basil leaves.

  16. Improvement in Flavonoids and Phenolic Acids Production and Pharmaceutical Quality of Sweet Basil (Ocimum basilicum L.) by Ultraviolet-B Irradiation.

    PubMed

    Ghasemzadeh, Ali; Ashkani, Sadegh; Baghdadi, Ali; Pazoki, Alireza; Jaafar, Hawa Z E; Rahmat, Asmah

    2016-01-01

    -B treated leaves presented the highest DPPH activity and antiproliferative activity with a half-maximal inhibitory concentration (IC50) value of 56.0 and 40.8 µg/mL, respectively, over that of the control plants (78.0 and 58.2 µg/mL, respectively). These observations suggest that post-harvest irradiation with UV-B can be considered a promising technique to improve the healthy-nutritional and pharmaceutical properties of sweet basil leaves. PMID:27618000

  17. Improving the performance of an aerobic membrane bioreactor (MBR) treating pharmaceutical wastewater with powdered activated carbon (PAC) addition.

    PubMed

    Kaya, Yasemin; Bacaksiz, A Murat; Golebatmaz, Ugur; Vergili, Ilda; Gönder, Z Beril; Yilmaz, Gulsum

    2016-04-01

    In this study, the effects of organic loading rate (OLR) and the addition of powdered activated carbon (PAC) on the performance and membrane fouling of MBR were conducted to treat real pharmaceutical process wastewater. Over 145 days of operation, the MBR system was operated at OLRs ranging from 1 to 2 kg COD m(-3) day(-1) without sludge wasting. The addition of PAC provided an improvement in the flux, despite an increase in the OLR:PAC ratio. The results demonstrated that the hybrid PAC-MBR system maintained a reduced amount of membrane fouling and steadily increased the removal performance of etodolac. PAC addition reduced the deposition of extracellular polymeric substance and organic matter on the membrane surface and resulted an increase in COD removal even at higher OLRs with low PAC addition. Membrane fouling mechanisms were investigated using combined adsorption fouling models. Modified fouling index values and normalized mass transfer coefficient values indicated that predominant fouling mechanism was cake adsorption. PMID:26846538

  18. Prediction of the Carcinogenic Potential of Human Pharmaceuticals Using Repeated Dose Toxicity Data and Their Pharmacological Properties

    PubMed Central

    van der Laan, Jan Willem; Buitenhuis, Wenny H. W.; Wagenaar, Laura; Soffers, Ans E. M. F.; van Someren, Eugene P.; Krul, Cyrille A. M.; Woutersen, Ruud A.

    2016-01-01

    In an exercise designed to reduce animal use, we analyzed the results of rat subchronic toxicity studies from 289 pharmaceutical compounds with the aim to predict the tumor outcome of carcinogenicity studies in this species. The results were obtained from the assessment reports available at the Medicines Evaluation Board of the Netherlands for 289 pharmaceutical compounds that had been shown to be non-genotoxic. One hundred forty-three of the 239 compounds not inducing putative preneoplastic lesions in the subchronic study did not induce tumors in the carcinogenicity study [true negatives (TNs)], whereas 96 compounds were categorized as false negatives (FNs) because tumors were observed in the carcinogenicity study. Of the remaining 50 compounds, 31 showed preneoplastic lesions in the subchronic study and tumors in the carcinogenicity study [true positives (TPs)], and 19 only showed preneoplastic lesions in subchronic studies but no tumors in the carcinogenicity study [false positives (FPs)]. In addition, we then re-assessed the prediction of the tumor outcome by integrating the pharmacological properties of these compounds. These pharmacological properties were evaluated with respect to the presence or absence of a direct or indirect proliferative action. We found support for the absence of cellular proliferation for 204 compounds (TN). For 67 compounds, the presence of cellular hyperplasia as evidence for proliferative action could be found (TP). Therefore, this approach resulted in an ability to predict non-carcinogens at a success rate of 92% and the ability to detect carcinogens at 98%. The combined evaluation of pharmacological and histopathological endpoints eventually led to only 18 unknown outcomes (17 categorized as FN and 1 as FP), thereby enhancing both the negative and positive predictivity of an evaluation based upon histopathological evaluation only. The data show the added value of a consideration of the pharmacological properties of compounds in

  19. Photorefractive polymer device with improved sensitizing property

    NASA Astrophysics Data System (ADS)

    Nguyen, Tam V.; Giang, Ha N.; Kinashi, K.; Sakai, W.; Tsutsumi, N.

    2015-09-01

    photorefractive (PR) application because of a fast hole mobility. In most of the previous studies, phenyl-C61-butyric acid methyl ester (PCBM) was used as a sensitizer. In this study, a high-performance charge generator perylene bisimide (PBI) is synthesized and added into the composite. PBI derivatives owning a large core of π-conjugated rings provide a high electron affinity and high charge carrier mobility. These features are promising to improve PR properties. To the best of our knowledge, it is the first time for using a combine of PCBM and PBI to improve the PR performance of PDAA-based composites. 2-(4-(azepan-1-yl)benzylidene)malononitrile (7-DCST) is used as a nonlinear optical chromophore. (4-diphenylamino)phenyl)methanol (TPAOH) is used as a plasticizer. Consequently, a diffraction efficiency of 76 % and a response time of 8 ms were obtained with 532 nm green laser under the electric field of 55 V μm-1. As a conclusion, the introduction of PBI is a promising approach for the photorefractive composite owning the video rate response.

  20. Adsorption of pharmaceutical excipients onto microcrystals of siramesine hydrochloride: effects on physicochemical properties.

    PubMed

    Zimmermann, Anne; Millqvist-Fureby, Anna; Elema, Michiel Ringkjøbing; Hansen, Tue; Müllertz, Anette; Hovgaard, Lars

    2009-01-01

    A common challenge in the development of new drug substances is poor dissolution characteristics caused by low aqueous solubility. In this study, microcrystals with optimized physicochemical properties were prepared by precipitation in the presence of excipients, which adsorbed to the particle surface and altered particle size, morphology, and dissolution rate. The poorly water-soluble drug siramesine hydrochloride was precipitated by the antisolvent method in the presence of each of various polymeric and surface active excipients. Powder dissolution studies of six of the resulting particle systems showed a significant increase in percent dissolved after 15 min compared to the starting material. A quantitative determination of the amount of excipient adsorbed to the surface of the drug particles proved that only a very small amount of excipient was needed to exert a marked effect on particle properties. The adsorbed amount of excipient constituted less than 1.4% (w/w) of the total particle weight, and thus powders of very high drug loads were obtained. Sodium lauryl sulphate (SLS), hydroxypropyl methylcellulose (HPMC), and hydroxypropyl cellulose (HPC), which exhibited the greatest degree of adsorption, also had the greatest effect on the physicochemical properties of the particles. X-ray Photoelectron Spectroscopy (XPS) analysis of the surface composition and scanning electron microscopy studies on particle morphology suggested that the excipients adsorbed to specific faces of the crystals.

  1. Pharmaceutical Psychology.

    ERIC Educational Resources Information Center

    Dolinsky, Donna

    1979-01-01

    Defines areas that could comprise pharmaceutical psychology. The discussion includes a review of literature, outline of areas in pharmacy in which psychologists could become involved, description of a project involving the application of psychology to pharmacy, and analysis of the concept of pharmaceutical psychology. A 99-item bibliography is…

  2. Preparation of a novel positively charged nanofiltration composite membrane incorporated with silver nanoparticles for pharmaceuticals and personal care product rejection and antibacterial properties.

    PubMed

    Huang, Zhong-Hua; Yin, Yan-Na; Aikebaier, Gu-li-mi-la; Zhang, Yan

    2016-01-01

    A novel positively charged N-[(2-hydroxy-3-trimethylammonium)propyl] chloride chitosan (HTCC)-Ag/polyethersulfone (PES) composite nanofiltration membrane was easily prepared by coating the active layer, HTCC, onto PES as the support through epichlorohydrin as the cross-linking reagent and nano-Ag particles as the introduced inorganic components. Scanning election microscopy, X-ray photoelectron spectroscopy, atomic force microscopy, and X-ray diffraction were employed to characterize the morphology of the resultant membranes, of which the molecular weight cut-off was about 941 Da. At 25 °C, the pure water permeability is 16.27 L/h·m(2)·MPa. Our results showed that the rejection of pharmaceuticals and personal care products (PPCPs) followed the sequence: atenolol > carbamazepine > ibuprofen, confirming that the membranes were positively charged. The antibacterial properties of the membranes were compared to elucidate the existence of Ag nanoparticles which help to improve antibacterial activity against Gram-negative Escherichia coli (DH5α, Rosetta) and Gram-positive Bacillus subtilis. The inhibition zone diameters of HTCC-Ag/PES membranes towards E. coli DH5α, E. coli Rosetta and Bacillus subtilis were 17.77, 16.18, and 15.44 mm, respectively. It was found that HTCC-Ag/PES membrane has a better antibacterial activity against E. coli than against Bacillus subtilis, especially for E. coli DH5α. PMID:27120646

  3. Preparation of a novel positively charged nanofiltration composite membrane incorporated with silver nanoparticles for pharmaceuticals and personal care product rejection and antibacterial properties.

    PubMed

    Huang, Zhong-Hua; Yin, Yan-Na; Aikebaier, Gu-li-mi-la; Zhang, Yan

    2016-01-01

    A novel positively charged N-[(2-hydroxy-3-trimethylammonium)propyl] chloride chitosan (HTCC)-Ag/polyethersulfone (PES) composite nanofiltration membrane was easily prepared by coating the active layer, HTCC, onto PES as the support through epichlorohydrin as the cross-linking reagent and nano-Ag particles as the introduced inorganic components. Scanning election microscopy, X-ray photoelectron spectroscopy, atomic force microscopy, and X-ray diffraction were employed to characterize the morphology of the resultant membranes, of which the molecular weight cut-off was about 941 Da. At 25 °C, the pure water permeability is 16.27 L/h·m(2)·MPa. Our results showed that the rejection of pharmaceuticals and personal care products (PPCPs) followed the sequence: atenolol > carbamazepine > ibuprofen, confirming that the membranes were positively charged. The antibacterial properties of the membranes were compared to elucidate the existence of Ag nanoparticles which help to improve antibacterial activity against Gram-negative Escherichia coli (DH5α, Rosetta) and Gram-positive Bacillus subtilis. The inhibition zone diameters of HTCC-Ag/PES membranes towards E. coli DH5α, E. coli Rosetta and Bacillus subtilis were 17.77, 16.18, and 15.44 mm, respectively. It was found that HTCC-Ag/PES membrane has a better antibacterial activity against E. coli than against Bacillus subtilis, especially for E. coli DH5α.

  4. Pharmaceutical properties of supramolecular assembly of co-loaded cardanol/triazole-halloysite systems.

    PubMed

    Massaro, Marina; Colletti, Carmelo G; Noto, Renato; Riela, Serena; Poma, Paola; Guernelli, Susanna; Parisi, Filippo; Milioto, Stefana; Lazzara, Giuseppe

    2015-01-30

    Halloysite nanotubes were explored as drug carrier for cardanol, which is considered as a promising natural anticancer active species. To this aim, besides the pristine nanoclay, a chemical modification of the nanocarrier was performed by attaching triazolium salts with different hydrophobicity at the outer surface of the hollow nanotubes. The interaction between cardanol and nanotubes was highlighted in solution by HPLC. This method proved the loading of the drug into the nanotubes. The solid dried complexes formed by pristine and modified halloysite with the cardanol were characterized by IR spectroscopy, thermogravimetric analysis as well as water contact angle to evidence the structure, thermal properties and wettability of the obtained materials. The kinetics of cardanol release as well as cell viability experiments provided promising results that put forward a new strategy for potential applications of cardanol as active antiproliferative molecule and clay nanotubes as drug carrier. PMID:25498322

  5. The properties and the use of substituted benzofuroxans in pharmaceutical and medicinal chemistry: a comprehensive review.

    PubMed

    Jovené, Cyril; Chugunova, Elena A; Goumont, Régis

    2013-06-01

    Since the synthesis of 4,6-dinitrobenzofuroxan in 1899 by Drost, benzofuroxans have attracted particular attention. This peculiar series of compounds exhibit a broad spectrum of biological activity including antibacterial, antifungal, antileukemic, acaricide and immunodepressive properties. These works embrace a period of more than 50 years since the pioneering paper of Gosh and Whitehouse and papers in this major field of the heterocyclic chemistry are still published in 2013. The review has been built in two independent parts. The first one is directly dedicated to the structure of substituted benzofuroxans and will show many medicinal applications of these compounds such as nitric oxide-releasing abilities, induction of oxidative stress, potent anti-cancer agents, anti-chagas agent, target for antiamoebic agent, Ca2+ channel blockers or cytotoxic, mutagenic and genotoxic agent… The second part of this review will be in close connection with the use of benzofuroxans as synthetic precursors in the preparation of new biological compounds such as quinoxaline dioxide, benzimidazole and phenazine derivatives. The interaction of substituted benzofuroxans with electron rich heterocycles or carbanions is the key step in the synthesis of these new biological active compounds. These derivatives can be used as cytotoxic drugs, antimycobacterial agent and display anti-malarial, antileishmanial and antituberculosis activity. The nature of the substituent linked to the carbocyclic ring of benzofuroxan is of primary importance to understand the medicinal properties of this family of compounds. For example, when benzofuroxans are substituted by electron-releasing substituents, the chemical reactivity is transferred from the carbocyclic ring to the furoxan ring.

  6. Cissus stem gum as potential dispersant in pharmaceutical liquid systems 2: The emulsifying and suspending properties.

    PubMed

    Alfa, J; Chukwu, A; Udeala, O K

    2001-01-01

    The emulsifying and suspending properties of a new gum derived from the stem of cissus rufescence family Amphelidaceae were studied. Stability of the liquid paraffin emulsions prepared using this mucilaginous substance was compared with that containing tragacanth or acacia. The rate of globule coalescence was determined using Sherman's equation for concentrated emulsions. The suspending ability of the polymer was compared with that of tragacanth or compound tragacanth. The rate of deflocculation, K, was found to obey a power law equation: beta t = beta 0 e-kt in zinc oxide suspensions. At concentrations above 0.75% w/v, cissus gum produced liquid paraffin emulsion with minimal separation. The rate of globule coalescence was in the order acacia > cissus > tragacanth and rate of creaming was tragacanth > acacia > cissus. At concentrations of 0.6 to 1.0% w/v, cissus gum produced highly flocculated zinc oxide suspensions, which exhibited good redispersibility. Stability of the agglomerated, dispersed particles was similar to that produced using tagacanth mucilage.

  7. Pharmaceutical cocrystals: walking the talk.

    PubMed

    Bolla, Geetha; Nangia, Ashwini

    2016-06-28

    Pharmaceutical cocrystals belong to a sub-class of cocrystals wherein one of the components is a drug molecule (or an active pharmaceutical ingredient, API) and the second is a benign food or drug grade additive (generally regarded as safe, GRAS). The two components are hydrogen-bonded in a fixed stoichiometric ratio in the crystal lattice. In the past decade, pharmaceutical cocrystals have demonstrated significant promise in their ability to modify the physicochemical and pharmacokinetic properties of drug substances, such as the solubility and dissolution rate, bioavailability, particle morphology and size, tableting and compaction, melting point, physical form, biochemical and hydration stability, and permeability. In this feature review, we highlight some prominent examples of drug cocrystals which exhibit variable hardness/softness and elasticity/plasticity depending on coformer selection, improvement of solubility and permeability in the same cocrystal, increase of the melting point for solid formulation, enhanced color performance, photostability and hydration stability, and a longer half-life. Cocrystals of flavanoids and polyphenols can make improved pharmaceuticals and also extend to the larger class of nutraceuticals. The application of crystal engineering to assemble ternary cocrystals expands this field to drug-drug cocrystals which may be useful in multi-drug resistance, mitigating side effects of drugs, or attenuating/enhancing drug action synergistically by rational selection. The advent of new techniques for structural characterization beyond the standard X-ray diffraction will provide a better understanding of drug phases which are at the borderline of crystalline-amorphous nature and even newer opportunities in the future. PMID:27278109

  8. Systematic screening of common wastewater-marking pharmaceuticals in urban aquatic environments: implications for environmental risk control.

    PubMed

    Zhou, Haidong; Zhang, Qingjun; Wang, Xuelian; Zhang, Qianqian; Ma, Lixin; Zhan, Yong

    2014-01-01

    In this report, we refer to pharmaceuticals that are widespread in the urban aquatic environment and that mainly originate from wastewater treatment plants or non-point source sewage as "wastewater-marking pharmaceuticals" (WWMPs). To some extent, they reflect the condition or trend of water contamination and also contribute to aquatic environmental risk assessment. The method reported here for screening typical WWMPs was proposed based on academic concerns about them and their concentrations present in the urban aquatic environment, as well as their properties of accumulation, persistence, eco-toxicity and related environmental risks caused by them. The screening system consisted of an initial screening system and a further screening system. In the former, pharmaceuticals were categorised into different evaluation levels, and in the latter, each pharmaceutical was given a normalised final evaluation score, which was the sum of every score for its properties of accumulation, persistence, eco-toxicity and environmental risk in the aquatic environment. The system was applied to 126 pharmaceuticals frequently detected in the aquatic environment. In the initial screening procedure, five pharmaceuticals were classified into the "high" category, 16 pharmaceuticals into the "medium" category, 15 pharmaceuticals into the "low" category and 90 pharmaceuticals into the "very low" category. Subsequently, further screening were conducted on 36 pharmaceuticals considered as being of "high", "medium" and "low" categories in the former system. We identified 7 pharmaceuticals with final evaluation scores of 1-10, 10 pharmaceuticals with scores of 11-15, 15 pharmaceuticals with scores from 16 to 20 and 4 pharmaceuticals with scores above 21. The results showed that this screening system could contribute to the effective selection of target WWMPs, which would be important for spatial-temporal dynamics, transference and pollution control of pharmaceuticals in the urban aquatic

  9. Internal multiple-scattering hole-enhanced Raman spectroscopy: improved backscattering Fourier transform Raman sampling in pharmaceutical tablets utilizing cylindrical-conical holes.

    PubMed

    Larkin, Peter J; Santangelo, Matthew; Šašiċ, Slobodan

    2012-08-01

    The benefits of Raman signal enhancement and improved measurement precision are demonstrated using 180° backscattering Fourier transform Raman (FT-Raman) spectroscopy from drilled cylindrical-conical holes within pharmaceutical tablet cores. Multiple scattering of the incident laser light within the holes results in an increased Raman signal due to the larger Raman sampling volume. This is important for overcoming typical sub-sampling issues encountered when employing FT-Raman backscattering of heterogeneous pharmaceutical tablets. Hole depth and diameter were found to be important experimental parameters and were optimized to yield the greatest signal enhancement. The FT-Raman spectra collected using backscattering from cylindrical-conical holes is compared to typical 180° backscattering from flat surfaces using tablet cores of Excedrin® and Vivarin®. Raman chemical images are used to establish a representative sampling area. We observe a three- to five-fold increase in the Raman intensity and a two-fold improvement in the measurement precision when sampling from cylindrical-conical holes rather than classic backscattering from flat tablet cores. Self-absorption effects on analyte band ratios are negligible in the fingerprint region but are more significant at the higher near-infrared (NIR) absorbances found in the C-H/O-H/-N-H stretching region. The sampling technique will facilitate developing quantitative FT-Raman methods for application to pharmaceutical tablets using the fingerprint spectral region.

  10. The extended pharmaceutical enterprise.

    PubMed

    Cavalla, David

    2003-03-15

    The availability of widespread contractual services led to the birth of the virtual company in the 1990s. As the concept has matured, and the biotechnology sector diversified, interchange of intellectual property in the form of collaborative and license arrangements opens up still further the opportunities for outsourced forms of pharmaceutical R&D. PMID:12623241

  11. Response properties of self-improving systems.

    PubMed

    Krakovsky, Andrey

    2016-04-01

    We observe that a sustained positivity (or negativity) of a system's second-order response will result in a directional change of the system's characteristics under the corresponding random exposure. We identify these changes with improvement (or decline) in the state of a system and introduce the concept of self-improving systems as systems which characteristics can sustainably improve under a random exposure. The resulting framework is of a general phenomenological nature and can be applied to complex systems across different areas of knowledge. PMID:27059562

  12. Improving powder flow properties of citric acid by crystal hydration.

    PubMed

    Sun, Changquan

    2009-05-01

    A batch of poorly flowing citric acid anhydrate was exposed to 69.9% relative humidity to prepare pure monohydrate with nearly identical particle size and morphology but different surface properties. Flow properties of the powders were tested using a ring shear cell. Results show the hydration can significantly improve flow properties of anhydrous citric acid.

  13. Search for improved fluorinated stationary phases for separation of fluorine-containing pharmaceuticals from their desfluoro analogs.

    PubMed

    Regalado, Erik L; Makarov, Alexey A; McClain, Ray; Przybyciel, Matthew; Welch, Christopher J

    2015-02-01

    Evaluation of a several fluorine-containing stationary phases for the chromatographic separation of fluorine-containing pharmaceuticals from their corresponding desfluoro analogs revealed a number of perfluoroaryl and perfluoroalky stationary phases that afford good separations. These fluorous stationary phases exhibit greater retention for the fluorine-containing compounds relative to the H-containing analogs, consistent with a fluorophilic retention mechanism. While both perfluoroalkyl and perfluoroaryl stationary phases afford adequate resolution, the perfluoroaryl columns generally exhibit superior separation factor (α) and peak efficiency (N), resulting in faster baseline separations, with the Hypersil Gold PFP and Poroshell 120 PFP columns providing the best overall performance for the test group studied.

  14. Search for improved fluorinated stationary phases for separation of fluorine-containing pharmaceuticals from their desfluoro analogs.

    PubMed

    Regalado, Erik L; Makarov, Alexey A; McClain, Ray; Przybyciel, Matthew; Welch, Christopher J

    2015-02-01

    Evaluation of a several fluorine-containing stationary phases for the chromatographic separation of fluorine-containing pharmaceuticals from their corresponding desfluoro analogs revealed a number of perfluoroaryl and perfluoroalky stationary phases that afford good separations. These fluorous stationary phases exhibit greater retention for the fluorine-containing compounds relative to the H-containing analogs, consistent with a fluorophilic retention mechanism. While both perfluoroalkyl and perfluoroaryl stationary phases afford adequate resolution, the perfluoroaryl columns generally exhibit superior separation factor (α) and peak efficiency (N), resulting in faster baseline separations, with the Hypersil Gold PFP and Poroshell 120 PFP columns providing the best overall performance for the test group studied. PMID:25595532

  15. Analyzing and improving viscoelastic properties of high density polyethylene

    NASA Astrophysics Data System (ADS)

    Ahmed, Reaj Uddin

    2011-12-01

    High Density Polyethylene (HDPE) is closely packed, less branched polyethylene having higher mechanical properties, chemical resistance, and heat resistance than Low Density Polyentylene (LDPE). Better properties and cost effectiveness make it an important raw material over LDPE in packaging industries. Stacked containers made of HDPE experience static loading and deformation strain during their storage period in a warehouse. As HDPE is a viscoelastic material, dimensional stability of stacked HDPE containers depends on time dependent properties such as creep and stress relaxation. Now, light weighting is a driving force in packaging industries, which results in lower production costs but performance of the product becomes a challenge. Proper understanding of the viscoelastic properties of HDPE, with relevant FE simulation can facilitate improved designs. This research involves understanding and improving viscoelastic properties, creep behavior, and stress relaxation of HDPE. Different approaches were carried out to meet the objectives. Organic filler CaCO3 was added to HDPE at increasing weight fractions and corresponding property changes were investigated. Annealing heat treatments were also carried out for potential property improvements. The effect of ageing was also investigated on both annealed and non annealed HDPE. The related performance of different water bottles against squeeze pressure was also characterized. Both approaches, incorporation of CaCO3 and annealing, showed improvements in the properties of HDPE over neat HDPE. This research aids finding the optimum solution for improving viscoelastic properties, stress relaxation, and creep behavior of HDPE in manufacturing.

  16. An improved approach to measuring drug innovation finds steady rates of first-in-class pharmaceuticals, 1987-2011.

    PubMed

    Lanthier, Michael; Miller, Kathleen L; Nardinelli, Clark; Woodcock, Janet

    2013-08-01

    For more than a decade, industry analysts and policy makers have raised concerns about declining pharmaceutical innovation, citing declining numbers of new molecular entities (NMEs) approved in the United States each year. Yet there is little consensus on whether this is the best measure of "innovation." We examined NME approvals during 1987-2011 and propose the three distinct subcategories of NMEs--first-in-class, advance-in-class, and addition-to-class--to provide more nuanced and informative insights into underlying trends. We found that trends in NME approvals were largely driven by addition-to-class, or "me too," drug approvals, while first-in-class approvals remained fairly steady over the study period. Moreover, the higher proportion of first-in-class drug approvals over the most recent decade is an encouraging sign of the health of the industry as a whole.

  17. Thin-coating as an alternative approach to improve flow properties of ibuprofen powder.

    PubMed

    Genina, Natalja; Räikkönen, Heikki; Ehlers, Henrik; Heinämäki, Jyrki; Veski, Peep; Yliruusi, Jouko

    2010-03-15

    In the present study, thin-coating as a potential method for improving flow properties of cohesive ibuprofen powder was introduced. Briefly, the technique was based on the successive deposition of ultrasound-assisted fine polymer mist onto the surface of the powdered active pharmaceutical ingredient (API), producing individual particles with a hydrophilic thin-coat. A 0.15% m/V aqueous solution of hydroxypropyl methylcellulose (HPMC) was used. Particle size and surface analysis revealed a decrease in the cohesiveness of ibuprofen powder and an increase in the homogeneity of particle surfaces as a result of polymer treatment. Superficial changes caused a substantial improvement on the flowing characteristics of coated substance over uncoated. The enhancement in flow rate proceeded as the uniformity of the HPMC layer increased. In conclusion, the proposed technique is a simple and effective method that can be used as a continuous process to modify API particle surface properties, which in turn improve the handling of poorly flowable powder.

  18. Improving the electrical properties of graphene layers by chemical doping

    NASA Astrophysics Data System (ADS)

    Farooq Khan, Muhammad; Zahir Iqbal, Muhammad; Waqas Iqbal, Muhammad; Eom, Jonghwa

    2014-10-01

    Although the electronic properties of graphene layers can be modulated by various doping techniques, most of doping methods cost degradation of structural uniqueness or electrical mobility. It is matter of huge concern to develop a technique to improve the electrical properties of graphene while sustaining its superior properties. Here, we report the modification of electrical properties of single- bi- and trilayer graphene by chemical reaction with potassium nitrate (KNO3) solution. Raman spectroscopy and electrical transport measurements showed the n-doping effect of graphene by KNO3. The effect was most dominant in single layer graphene, and the mobility of single layer graphene was improved by the factor of more than 3. The chemical doping by using KNO3 provides a facile approach to improve the electrical properties of graphene layers sustaining their unique characteristics.

  19. Improving Search Properties in Genetic Programming

    NASA Technical Reports Server (NTRS)

    Janikow, Cezary Z.; DeWeese, Scott

    1997-01-01

    developed and implemented methods to use additional problem heuristics to fine-tune the searchable space, and to use typing information to further reduce the search space. Additional improvements have been proposed, but they are yet to be explored and implemented.

  20. Photochemical Mechanism of Riboflavin-Induced Degradation of Famotidine and a Suggested Pharmaceutical Strategy for Improving Photostability.

    PubMed

    Uchida, Atsushi; Onoue, Satomi; Ohtake, Hiroto; Seto, Yoshiki; Teramatsu, Tsuyoshi; Terajima, Tomoko; Oguchi, Toshio

    2016-02-01

    The present study aimed to clarify the mechanism of photodegradation of famotidine with riboflavin (FMT/RF), and to develop a photochemically stabilized formulation of FMT/RF. Photochemical properties of RF were characterized by UV-VIS spectral analysis, reactive oxygen species (ROS) assay, and photostability testing. Pharmacokinetic study was conducted in rats after intravenous administration of FMT (1 mg/kg) formulation containing RF (0.01 mg/kg). The UV-VIS spectral pattern of RF partly overlapped with the sunlight spectrum, and ROS generation from photoirradiated RF was remarkable; thus, RF had high photoreactive potential. In the photostability testing, after irradiation (250 W/m(2)), degradation rate for FMT in FMT/RF was ca. 11-fold higher than that in FMT alone. The addition of radical scavengers to FMT/RF led to attenuated photodegradation of FMT/RF; in particular, the addition of L-ascorbic acid (vitamin C; VC) to FMT/RF showed ca. 86% inhibition of the photodegradation of FMT/RF. The pharmacokinetic study on FMT indicated that the addition of VC (1 mg/kg) to FMT/RF had no significant impact on the pharmacokinetic behavior of FMT. These findings suggest that ROS-mediated photochemical reaction would be involved in the photodegradation pathway of FMT/RF, and the complementary use of VC might be an attractive approach to improve the photostability of FMT/RF. PMID:26505739

  1. Photochemical Mechanism of Riboflavin-Induced Degradation of Famotidine and a Suggested Pharmaceutical Strategy for Improving Photostability.

    PubMed

    Uchida, Atsushi; Onoue, Satomi; Ohtake, Hiroto; Seto, Yoshiki; Teramatsu, Tsuyoshi; Terajima, Tomoko; Oguchi, Toshio

    2016-02-01

    The present study aimed to clarify the mechanism of photodegradation of famotidine with riboflavin (FMT/RF), and to develop a photochemically stabilized formulation of FMT/RF. Photochemical properties of RF were characterized by UV-VIS spectral analysis, reactive oxygen species (ROS) assay, and photostability testing. Pharmacokinetic study was conducted in rats after intravenous administration of FMT (1 mg/kg) formulation containing RF (0.01 mg/kg). The UV-VIS spectral pattern of RF partly overlapped with the sunlight spectrum, and ROS generation from photoirradiated RF was remarkable; thus, RF had high photoreactive potential. In the photostability testing, after irradiation (250 W/m(2)), degradation rate for FMT in FMT/RF was ca. 11-fold higher than that in FMT alone. The addition of radical scavengers to FMT/RF led to attenuated photodegradation of FMT/RF; in particular, the addition of L-ascorbic acid (vitamin C; VC) to FMT/RF showed ca. 86% inhibition of the photodegradation of FMT/RF. The pharmacokinetic study on FMT indicated that the addition of VC (1 mg/kg) to FMT/RF had no significant impact on the pharmacokinetic behavior of FMT. These findings suggest that ROS-mediated photochemical reaction would be involved in the photodegradation pathway of FMT/RF, and the complementary use of VC might be an attractive approach to improve the photostability of FMT/RF.

  2. Pharmaceutical virtue.

    PubMed

    Martin, Emily

    2006-06-01

    In the early history of psychopharmacology, the prospect of developing technologically sophisticated drugs to alleviate human ills was surrounded with a fervor that could be described as religious. This paper explores the subsequent history of the development of psychopharmacological agents, focusing on the ambivalent position of both the industry and its employees. Based on interviews with retired pharmaceutical employees who were active in the industry in the 1950s and 1960s when the major breakthroughs were made in the development of MAOIs and SSRIs, the paper explores the initial development of educational materials for use in sales campaigns. In addition, based on interviews with current employees in pharmaceutical sales and marketing, the paper describes the complex perspective of contemporary pharmaceutical employees who must live surrounded by the growing public vilification of the industry as rapacious and profit hungry and yet find ways to make their jobs meaningful and dignified. The paper will contribute to the understudied problem of how individuals function in positions that require them to be part of processes that on one description constitute a social evil, but on another, constitute a social good.

  3. Trade, TRIPS, and pharmaceuticals.

    PubMed

    Smith, Richard D; Correa, Carlos; Oh, Cecilia

    2009-02-21

    The World Trade Organization's Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) set global minimum standards for the protection of intellectual property, substantially increasing and expanding intellectual-property rights, and generated clear gains for the pharmaceutical industry and the developed world. The question of whether TRIPS generates gains for developing countries, in the form of increased exports, is addressed in this paper through consideration of the importance of pharmaceuticals in health-care trade, outlining the essential requirements, implications, and issues related to TRIPS, and TRIPS-plus, in which increased restrictions are imposed as part of bilateral free-trade agreements. TRIPS has not generated substantial gains for developing countries, but has further increased pharmaceutical trade in developed countries. The unequal trade between developed and developing countries (ie, exporting and importing high-value patented drugs, respectively) raises the issue of access to medicines, which is exacerbated by TRIPS-plus provisions, although many countries have not even enacted provision for TRIPS flexibilities. Therefore this paper focuses on options that are available to the health community for negotiation to their advantage under TRIPS, and within the presence of TRIPS-plus.

  4. Trade, TRIPS, and pharmaceuticals.

    PubMed

    Smith, Richard D; Correa, Carlos; Oh, Cecilia

    2009-02-21

    The World Trade Organization's Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) set global minimum standards for the protection of intellectual property, substantially increasing and expanding intellectual-property rights, and generated clear gains for the pharmaceutical industry and the developed world. The question of whether TRIPS generates gains for developing countries, in the form of increased exports, is addressed in this paper through consideration of the importance of pharmaceuticals in health-care trade, outlining the essential requirements, implications, and issues related to TRIPS, and TRIPS-plus, in which increased restrictions are imposed as part of bilateral free-trade agreements. TRIPS has not generated substantial gains for developing countries, but has further increased pharmaceutical trade in developed countries. The unequal trade between developed and developing countries (ie, exporting and importing high-value patented drugs, respectively) raises the issue of access to medicines, which is exacerbated by TRIPS-plus provisions, although many countries have not even enacted provision for TRIPS flexibilities. Therefore this paper focuses on options that are available to the health community for negotiation to their advantage under TRIPS, and within the presence of TRIPS-plus. PMID:19167054

  5. [Pharmaceutical chemistry of general anaesthetics].

    PubMed

    Szász, György; Takácsné, Novák Krisztina

    2004-01-01

    The paper represents the first part of a planned series of reviews about pharmaceutical chemistry of drugs acting on the central nervous system. The authorial aim and editorial concepts are the same were followed in a former series of papers about pharmaceutical chemistry of agents effecting the heart, blood circulation and vegetative nervous system. Consequently, general anaesthetics are discussed in the present paper through the chapters "history, preparation; structure-properties-activity; application; analysis".

  6. Modification of physicochemical characteristics of active pharmaceutical ingredients and application of supersaturatable dosage forms for improving bioavailability of poorly absorbed drugs.

    PubMed

    Kawakami, Kohsaku

    2012-05-01

    New chemical entities are required to possess physicochemical characteristics that result in acceptable oral absorption. However, many promising candidates need physicochemical modification or application of special formulation technology. This review discusses strategies for overcoming physicochemical problems during the development at the preformulation and formulation stages with emphasis on overcoming the most typical problem, low solubility. Solubility of active pharmaceutical ingredients can be improved by employing metastable states, salt forms, or cocrystals. Since the usefulness of salt forms is well recognized, it is the normal strategy to select the most suitable salt form through extensive screening in the current developmental study. Promising formulation technologies used to overcome the low solubility problem include liquid-filled capsules, self-emulsifying formulations, solid dispersions, and nanosuspensions. Current knowledge for each formulation is discussed from both theoretical and practical viewpoints, and their advantages and disadvantages are presented.

  7. Melding regulatory, pharmaceutical industry, and U.S. payer perspectives on improving approaches to heterogeneity of treatment effect in research and practice.

    PubMed

    Willke, Richard J; Crown, William; Del Aguila, Michael; Cziraky, Mark J; Khan, Zeba M; Migliori, Richard

    2013-01-01

    Effective pursuit of the science and management of heterogeneity of treatment effect (HTE) relies on the mutual understanding of the perspectives of, and collaboration among, the various stakeholders in health care. In this article, we compare, contrast, and endeavor to find areas of alignment across the perspectives of three such stakeholders -regulators, the biopharmaceutical and device industry, and U.S. payers. First, we discuss how evidence of HTE is generated and could be improved upon. For pharmaceuticals, much of the initial research is conducted by the pharmaceutical industry, guided by basic science but also delimited by potential markets, regulatory approval requirements, trial size considerations, and payer expectations for evidence of value. Once a drug is marketed, further evidence can be generated via combining trial data, conducting meta-analysis, and analyzing real-world results through observational research designs; we explore how these efforts can benefit from cooperation across these stakeholders. Second, we discuss the equally important utilization of HTE evidence so that physicians and patients have access to and can benefit from the learnings from this research. Research findings must be translated into actionable information and guidelines that can be incorporated into everyday practice. Doing so requires interaction and collaboration among all involved, based on facilitated communication as well as further evaluation research. We provide examples of several cross-sectorial initiatives that are under way in this area. Finally, we explore some economic aspects of HTE research as part of the drug development, marketing, and treatment process. Understanding the economic incentives present is fundamental to aligning those incentives to improve the availability and utilization of HTE evidence. Clear understandings among regulators, pharma, and payers about high-value targets, methods to efficiently generate and communicate information, and value

  8. Melding regulatory, pharmaceutical industry, and U.S. payer perspectives on improving approaches to heterogeneity of treatment effect in research and practice.

    PubMed

    Willke, Richard J; Crown, William; Del Aguila, Michael; Cziraky, Mark J; Khan, Zeba M; Migliori, Richard

    2013-01-01

    Effective pursuit of the science and management of heterogeneity of treatment effect (HTE) relies on the mutual understanding of the perspectives of, and collaboration among, the various stakeholders in health care. In this article, we compare, contrast, and endeavor to find areas of alignment across the perspectives of three such stakeholders -regulators, the biopharmaceutical and device industry, and U.S. payers. First, we discuss how evidence of HTE is generated and could be improved upon. For pharmaceuticals, much of the initial research is conducted by the pharmaceutical industry, guided by basic science but also delimited by potential markets, regulatory approval requirements, trial size considerations, and payer expectations for evidence of value. Once a drug is marketed, further evidence can be generated via combining trial data, conducting meta-analysis, and analyzing real-world results through observational research designs; we explore how these efforts can benefit from cooperation across these stakeholders. Second, we discuss the equally important utilization of HTE evidence so that physicians and patients have access to and can benefit from the learnings from this research. Research findings must be translated into actionable information and guidelines that can be incorporated into everyday practice. Doing so requires interaction and collaboration among all involved, based on facilitated communication as well as further evaluation research. We provide examples of several cross-sectorial initiatives that are under way in this area. Finally, we explore some economic aspects of HTE research as part of the drug development, marketing, and treatment process. Understanding the economic incentives present is fundamental to aligning those incentives to improve the availability and utilization of HTE evidence. Clear understandings among regulators, pharma, and payers about high-value targets, methods to efficiently generate and communicate information, and value

  9. Recognizing misleading pharmaceutical marketing online.

    PubMed

    De Freitas, Julian; Falls, Brian A; Haque, Omar S; Bursztajn, Harold J

    2014-01-01

    In light of decision-making psychology, this article details how drug marketing operates across established and novel web domains and identifies some common misleading trends and influences on prescribing and patient-initiated medication requests. The Internet has allowed pharmaceutical marketing to become more salient than ever before. Although the Internet's growth has improved the dissemination of pharmaceutical information, it has also led to the increased influence of misleading pharmaceutical marketing. Such mismarketing is of concern, especially in psychiatry, since psychotropics generate considerable revenue for drug companies. In a climate of resource-limited drug regulation and time-strapped physicians, we recommend improving both independent monitoring and consumer awareness of Internet-enabled, potentially misleading, pharmaceutical marketing influences.

  10. Transdermal Drug Delivery: Innovative Pharmaceutical Developments Based on Disruption of the Barrier Properties of the stratum corneum

    PubMed Central

    Zaid Alkilani, Ahlam; McCrudden, Maelíosa T.C.; Donnelly, Ryan F.

    2015-01-01

    The skin offers an accessible and convenient site for the administration of medications. To this end, the field of transdermal drug delivery, aimed at developing safe and efficacious means of delivering medications across the skin, has in the past and continues to garner much time and investment with the continuous advancement of new and innovative approaches. This review details the progress and current status of the transdermal drug delivery field and describes numerous pharmaceutical developments which have been employed to overcome limitations associated with skin delivery systems. Advantages and disadvantages of the various approaches are detailed, commercially marketed products are highlighted and particular attention is paid to the emerging field of microneedle technologies. PMID:26506371

  11. Improvement of materials surface properties by rf glow discharge treatment

    SciTech Connect

    Huang, T.B.; Chen, X.; Tian, X.Q.; Cha, L.Z.

    2006-07-15

    Materials surface properties were improved by the application of a rf glow discharge treatment for vacuum and electronic applications. The surface morphology was studied under different glow discharge treatments and it could be shown by experiments that the roughness of materials surface varied due to the glow discharge treating process and that a clean and smooth surface could be obtained after the treatment. The experimental results revealed that the outgassing rates for different gases decreased and the evacuating properties for the materials improved following the application of the glow discharge treatment.

  12. Pharmaceutical Analysis as a Branch of Pharmaceutics

    ERIC Educational Resources Information Center

    Connors, Kenneth A.

    1977-01-01

    Pharmaceutical analysis is incorporated into the pharmaceutics component of the undergraduate curriculum at the University of Wisconsin. Many collaborative demonstrations, lectures, and laboratory experiments can illustrate the close relationship between analysis and modern pharmacy practice. (Author/LBH)

  13. Generic Selection Criteria for Safety and Patient Benefit [IV] - Physicochemical and pharmaceutical properties of brand-name and generic ketoprofen tapes.

    PubMed

    Wada, Yuko; Kihara, Maki; Nozawa, Mitsuru; Shimokawa, Ken-Ichi; Ishii, Fumiyoshi

    2015-06-01

    The physicochemical and pharmaceutical properties (pH, peel force, water-vapor permeability, and stretchability) of brand-name and generic ketoprofen products were evaluated and compared. The pHs of Mohrus as a brand-name product and Teikoku as a generic product were low (about 4). Among the other generic products, Patell and Nichi-Iko had a pH of about 4.3 while Frestol, Raynanon, BMD, and Touchron showed a pH of 4.6-5.2, which was in the pH range of normal healthy skin (4.5-6.5). The adhesive force was high (≥ 1.38) for Mohrus as a brand-name product as well as for Teikoku and Patell as generic products, but it was low (≤ 0.57) for the other 5 generic products. The water-vapor permeabilities of Mohrus as a brand-name product and Teikoku and Patell as generic products were low, being less than 1/6 of those for the other 5 generic products. Among the 5 generic products, BMD showed the highest water-vapor permeability (1,330 g/m²), and the other products also showed a value ≥ 1,100 g/m². The elongatedness of Mohrus was the lowest (15.5 cm), and that of Raynanon was the highest (24.5 cm); the difference was 9 cm. In this study, the physiochemical and pharmaceutical properties of ketoprofen tapes were clarified, which will allow pharmacists to provide products according to the needs of each patient when a brand-name product is changed to a generic one.

  14. Improving cochlear implant properties through conductive hydrogel coatings.

    PubMed

    Hassarati, Rachelle T; Dueck, Wolfram F; Tasche, Claudia; Carter, Paul M; Poole-Warren, Laura A; Green, Rylie A

    2014-03-01

    Conductive hydrogel (CH) coatings for biomedical electrodes have shown considerable promise in improving electrode mechanical and charge transfer properties. While they have desirable properties as a bulk material, there is limited understanding of how these properties translate to a microelectrode array. This study evaluated the performance of CH coatings applied to Nucleus Contour Advance cochlear electrode arrays. Cyclic voltammetry and biphasic stimulation were carried out to determine electrical properties of the coated arrays. Electrical testing demonstrated that CH coatings supported up to 24 times increase in charge injection limit. Reduced impedance was also maintained for over 1 billion stimulations without evidence of delamination or degradation. Mechanical studies performed showed negligible effect of the coating on the pre-curl structure of the Contour Advance arrays. Testing the coating in a model human scala tympani confirmed that adequate contact was maintained across the lateral wall. CH coatings are a viable, stable coating for improving electrical properties of the platinum arrays while imparting a softer material interface to reduce mechanical mismatch. Ultimately, these coatings may act to minimize scar tissue formation and fluid accumulation around electrodes and thus improve the electrical performance of neural implants.

  15. Optical properties of volcanic ash: improving remote sensing observations.

    NASA Astrophysics Data System (ADS)

    Whelley, Patrick; Colarco, Peter; Aquila, Valentina; Krotkov, Nickolay; Bleacher, Jake; Garry, Brent; Young, Kelsey; Rocha Lima, Adriana; Martins, Vanderlei; Carn, Simon

    2016-04-01

    Many times each year explosive volcanic eruptions loft ash into the atmosphere. Global travel and trade rely on aircraft vulnerable to encounters with airborne ash. Volcanic ash advisory centers (VAACs) rely on dispersion forecasts and satellite data to issue timely warnings. To improve ash forecasts model developers and satellite data providers need realistic information about volcanic ash microphysical and optical properties. In anticipation of future large eruptions we can study smaller events to improve our remote sensing and modeling skills so when the next Pinatubo 1991 or larger eruption occurs, ash can confidently be tracked in a quantitative way. At distances >100km from their sources, drifting ash plumes, often above meteorological clouds, are not easily detected from conventional remote sensing platforms, save deriving their quantitative characteristics, such as mass density. Quantitative interpretation of these observations depends on a priori knowledge of the spectral optical properties of the ash in UV (>0.3μm) and TIR wavelengths (>10μm). Incorrect assumptions about the optical properties result in large errors in inferred column mass loading and size distribution, which misguide operational ash forecasts. Similarly, simulating ash properties in global climate models also requires some knowledge of optical properties to improve aerosol speciation.

  16. 24 CFR 201.20 - Property improvement loan eligibility.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Property improvement loan eligibility. 201.20 Section 201.20 Housing and Urban Development Regulations Relating to Housing and Urban... HOUSING AND URBAN DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND...

  17. Effect of oxygenates blending with gasoline to improve fuel properties

    NASA Astrophysics Data System (ADS)

    Babazadeh Shayan, Soheil; Seyedpour, Seyed Morteza; Ommi, Fathollah

    2012-07-01

    The purpose of this paper is to study the effect of oxygenate additives into gasoline for the improvement of physicochemical properties of blends. Methyl Tertiary Butyl Ether (MTBE), Methanol, Tertiary butyl alcohol (TBA), and Tertiary amyl alcohol (TAA) blend into unleaded gasoline with various blended rates of 2.5%, 5%, 7.5%, 10%, 15%, and 20%. Physicochemical properties of blends are analyzed by the standard American Society of Testing and Materials (ASTM) methods. Methanol, TBA, and TAA increase density of the mixtures, but MTBE decreases density. The addition of oxygenates lead to a distortion of the base gasoline's distillation curves. The Reid vapor pressure (RVP) of gasoline is found to increase with the addition of the oxygenated compounds. All oxygenates improve both motor and research octane numbers. Among these four additives, TBA shows the best fuel properties.

  18. The Pharmaceutical Commons

    PubMed Central

    Lezaun, Javier

    2015-01-01

    In the last decade, the organization of pharmaceutical research on neglected tropical diseases has undergone transformative change. In a context of perceived “market failure,” the development of new medicines is increasingly handled by public-private partnerships. This shift toward hybrid organizational models depends on a particular form of exchange: the sharing of proprietary assets in general and of intellectual property rights in particular. This article explores the paradoxical role of private property in this new configuration of global health research and development. Rather than a tool to block potential competitors, proprietary assets function as a lever to attract others into risky collaborative ventures; instead of demarcating public and private domains, the sharing of property rights is used to increase the porosity of that boundary. This reimagination of the value of property is connected to the peculiar timescape of global health drug development, a promissory orientation to the future that takes its clearest form in the centrality of “virtual” business models and the proliferation of strategies of deferral. Drawing on the anthropological literature on inalienable possessions, we reconsider property’s traditional exclusionary role and discuss the possibility that the new pharmaceutical “commons” proclaimed by contemporary global health partnerships might be the precursor of future enclosures. PMID:25866425

  19. Improvement of physicochemical properties of an antiepileptic drug by salt engineering.

    PubMed

    Rahman, Ziyaur; Zidan, Ahmed S; Samy, Raghu; Sayeed, Vilayat A; Khan, Mansoor A

    2012-09-01

    The focus of the present investigation was to evaluate the feasibility of using cyclamic salt of lamotrigine in order to improve its solubility and intrinsic dissolution rate (IDR). The salt was prepared by solution crystallization method and characterized chemically by fourier transform infrared spectroscopy (FTIR), proton ((1)H) and carbon ((13)C) nuclear magnetic resonance (liquid and solid, NMR) spectroscopy, physically by powder X-ray diffraction (PXRD), thermally by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), physicochemically for solubility, IDR, solution and solid-state stability, and polymorphism by solution recrystallization and slurry conversion studies. The FTIR, NMR, PXRD, DSC, and TGA spectra and thermograms indicated the salt formation. The salt formation increased lamotrigine solubility by 19-fold and IDR by 4.9-fold in water. The solution and solid-state stability were similar to parent molecule and were resistant to polymorphic transformation. In conclusion, cyclamic salt of lamotrigine provides another potential avenue for the pharmaceutical development of lamotrigine with improved physicochemical properties especially for pediatric population. It is also possible that appropriate dosage forms can be formulated with much lower drug amount and better safety profile than existing products. PMID:22588676

  20. Optical Properties of Volcanic Ash: Improving Remote Sensing Observations

    NASA Astrophysics Data System (ADS)

    Whelley, P.; Colarco, P. R.; Aquila, V.; Krotkov, N. A.; Bleacher, J. E.; Garry, W. B.; Young, K. E.; Lima, A. R.; Martins, J. V.; Carn, S. A.

    2015-12-01

    Many times each year explosive volcanic eruptions loft ash into the atmosphere. Global travel and trade rely on aircraft vulnerable to encounters with airborne ash. Volcanic ash advisory centers (VAACs) rely on dispersion forecasts and satellite data to issue timely warnings. To improve ash forecasts model developers and satellite data providers need realistic information about volcanic ash microphysical and optical properties. In anticipation of future large eruptions we can study smaller events to improve our remote sensing and modeling skills so when the next Pinatubo 1991 or larger eruption occurs, ash can confidently be tracked in a quantitative way. At distances >100km from their sources, drifting ash plumes, often above meteorological clouds, are not easily detected from conventional remote sensing platforms, save deriving their quantitative characteristics, such as mass density. Quantitative interpretation of these observations depends on a priori knowledge of the spectral optical properties of the ash in UV (>0.3μm) and TIR wavelengths (>10μm). Incorrect assumptions about the optical properties result in large errors in inferred column mass loading and size distribution, which misguide operational ash forecasts. Similarly, simulating ash properties in global climate models also requires some knowledge of optical properties to improve aerosol speciation. Recent research has identified a wide range in volcanic ash optical properties among samples collected from the ground after different eruptions. The database of samples investigated remains relatively small, and measurements of optical properties at the relevant particle sizes and spectral channels are far from complete. Generalizing optical properties remains elusive, as does establishing relationships between ash composition and optical properties, which are essential for satellite retrievals. We are building a library of volcanic ash optical and microphysical properties. In this presentation we show

  1. Alkyl glucopyranoside-based niosomes containing methotrexate for pharmaceutical applications: evaluation of physico-chemical and biological properties.

    PubMed

    Muzzalupo, Rita; Tavano, Lorena; La Mesa, Camillo

    2013-12-15

    We designed novel niosomes based on alkyl glucopyranoside surfactants and containing methotrexate as anticancer drug, to be used in the pharmaceutical field. The effects of surfactants with chains of different length on niosome size and their distribution, drug entrapment efficiencies and in vitro drug release were determined. Systems made of alkyl glucopyranosides and cholesterol form vesicles whose average size scales with the alkyl chains length of such surfactants. Vesicles size ranges between 300 and 500 nm, with low polydispersity index. In addition, the hemolytic activity of alkyl glucopyranosides as surfactant solutions or vesicular formulations was studied and compared, to identify possible structure-activity relationships. High methotrexate entrapment efficiency was obtained, confirming significant interactions between the drug and the niosomal matrices. After 24h the amount of methotrexate released from niosomal formulations is effectively delayed, compared to the free drug in solution. Hemolytic tests show that sugar-based surfactants are more hemolytic the longer is their alkyl chain. When the surfactants are in vesicular form, the reverse behavior holds. It was also inferred that vesicle formation reduces the surfactant toxicity. These niosomal formulations can be used as methotrexate delivery systems in anticancer therapy.

  2. Improved wear properties of high energy ion-implanted polycarbonate

    SciTech Connect

    Rao, G.R.; Lee, E.H. ); Bhattacharya, R.; McCormick, A.W. )

    1995-01-01

    Polycarbonate (Lexan[sup TM]) (PC) was implanted with 2 MeV B[sup +] and O[sup +] ions separately to fluences of 5[times]10[sup 17], 1[times]10[sup 18], and 5[times]10[sup 18] ions/m[sup 2], and characterized for changes in surface hardness and tribological properties. Results of tests showed that hardness values of all implanted specimens increased over those of the unirradiated material, and the O[sup +] implantation was more effective in improving hardness for a given fluence than the B[sup +] implantation. Reciprocating sliding wear tests using a nylon ball counterface yielded significant improvements for all implanted specimens except for the 5[times]10[sup 17] ions/m[sup 2] B[sup +]-implanted PC. Wear tests conducted with a 52100 steel ball yielded significant improvements for the highest fluence of 5[times]10[sup 18] ions/m[sup 2] for both ions, but not for the two lower fluences. The improvements in properties were related to Linear Energy Transfer (LET) mechanisms, where it was shown that the O[sup +] implantation caused greater ionization, thereby greater cross-linking at the surface corresponding to much better improvements in properties. The results were also compared with a previous study on PC using 200 keV B[sup +] ions. The present study indicates that high energy ion irradiation produces thicker, more cross-linked, harder, and more wear-resistant surfaces on polymers and thereby improves properties to a greater extent and more efficiently than lower energy ion implantation.

  3. Engineered disulfides improve mechanical properties of recombinant spider silk

    PubMed Central

    Grip, S; Johansson, J; Hedhammar, M

    2009-01-01

    Nature's high-performance polymer, spider silk, is composed of specific proteins, spidroins, which form solid fibers. So far, fibers made from recombinant spidroins have failed in replicating the extraordinary mechanical properties of the native material. A recombinant miniature spidroin consisting of four poly-Ala/Gly-rich tandem repeats and a nonrepetitive C-terminal domain (4RepCT) can be isolated in physiological buffers and undergoes self assembly into macrofibers. Herein, we have made a first attempt to improve the mechanical properties of 4RepCT fibers by selective introduction of AA → CC mutations and by letting the fibers form under physiologically relevant redox conditions. Introduction of AA → CC mutations in the first poly-Ala block in the miniature spidroin increases the stiffness and tensile strength without changes in ability to form fibers, or in fiber morphology. These improved mechanical properties correlate with degree of disulfide formation. AA → CC mutations in the forth poly-Ala block, however, lead to premature aggregation of the protein, possibly due to disulfide bonding with a conserved Cys in the C-terminal domain. Replacement of this Cys with a Ser, lowers thermal stability but does not interfere with dimerization, fiber morphology or tensile strength. These results show that mutagenesis of 4RepCT can reveal spidroin structure-activity relationships and generate recombinant fibers with improved mechanical properties. PMID:19388023

  4. Toward a definition of pharmaceutical innovation.

    PubMed

    Morgan, Steven; Lopert, Ruth; Greyson, Devon

    2008-01-01

    ONGOING DEBATES IN THE PHARMACEUTICAL SECTOR ABOUT INTELLECTUAL PROPERTY, PRICING AND REIMBURSEMENT, AND PUBLIC RESEARCH INVESTMENTS HAVE A COMMON DENOMINATOR: the pursuit of innovation. However, there is little clarity about what constitutes a true pharmaceutical innovation, and as a result there is confusion about what kind of new products should be pursued, protected and encouraged through health policy and clinical practice. If the concept of pharmaceutical innovation can be clarified, then it may become easier for health policy-makers and practitioners to evaluate, adopt and procure products in ways that appropriately recognize, encourage and give priority to truly valuable pharmaceutical innovations.

  5. In Silico Models for Ecotoxicity of Pharmaceuticals.

    PubMed

    Roy, Kunal; Kar, Supratik

    2016-01-01

    Pharmaceuticals and their active metabolites are one of the significantly emerging environmental toxicants. The major routes of entry of pharmaceuticals into the environment are industries, hospitals, or direct disposal of unwanted or expired drugs made by the patient. The most important and distinct features of pharmaceuticals are that they are deliberately designed to have an explicit mode of action and designed to exert an effect on humans and other living systems. This distinctive feature makes pharmaceuticals and their metabolites different from other chemicals, and this necessitates the evaluation of the direct effects of pharmaceuticals in various environmental compartments as well as to living systems. In this background, the alarming situation of ecotoxicity of diverse pharmaceuticals have forced government and nongovernment regulatory authorities to recommend the application of in silico methods to provide quick information about the risk assessment and fate properties of pharmaceuticals as well as their ecological and indirect human health effects. This chapter aims to offer information regarding occurrence of pharmaceuticals in the environment, their persistence, environmental fate, and toxicity as well as application of in silico methods to provide information about the basic risk management and fate prediction of pharmaceuticals in the environment. Brief ideas about toxicity endpoints, available ecotoxicity databases, and expert systems employed for rapid toxicity predictions of ecotoxicity of pharmaceuticals are also discussed.

  6. Nanostructured materials in electroanalysis of pharmaceuticals.

    PubMed

    Rahi, A; Karimian, K; Heli, H

    2016-03-15

    Basic strategies and recent developments for the enhancement of the sensory performance of nanostructures in the electroanalysis of pharmaceuticals are reviewed. A discussion of the properties of nanostructures and their application as modified electrodes for drug assays is presented. The electrocatalytic effect of nanostructured materials and their application in determining low levels of drugs in pharmaceutical forms and biofluids are discussed.

  7. Improvement of barrier properties of rotomolded PE containers with nanoclay

    SciTech Connect

    Jamshidi, Shadi; Sundararaj, Uttandaraman

    2015-05-22

    Polyethylene (PE) is widely used to make bulk containers in rotational molding process. The challenge in this study is to improve permeation resistance of PE to hydrocarbon solvents and gases. Adding organomodified clay improves the thermal, barrier and mechanical properties of PE. In fact, clay layers create a tortuous path against the permeant, yielding better barrier properties. Due to the non-polar hydrophobic nature of PE and polar hydrophilic structure of clay minerals, the compatibilizer plays a crucial role to enhance the dispersion level of clay in the matrix. In this study High Density Polyethylene (HDPE) and Linear Low Density Polyethylene (LLDPE) layered silicate nanocomposite were melt-compounded with two concentrations of organomodified clay (2 and 4 wt. %). The interaction between nanoclay, compatibilizer and rotomolding grade of PE were examined by using X-ray diffraction, transmission electron microscopy (TEM) and rheology test. Rheology was used to determine the performance of our material at low shear processing condition.

  8. Improvement of barrier properties of rotomolded PE containers with nanoclay

    NASA Astrophysics Data System (ADS)

    Jamshidi, Shadi; Sundararaj, Uttandaraman

    2015-05-01

    Polyethylene (PE) is widely used to make bulk containers in rotational molding process. The challenge in this study is to improve permeation resistance of PE to hydrocarbon solvents and gases. Adding organomodified clay improves the thermal, barrier and mechanical properties of PE. In fact, clay layers create a tortuous path against the permeant, yielding better barrier properties. Due to the non-polar hydrophobic nature of PE and polar hydrophilic structure of clay minerals, the compatibilizer plays a crucial role to enhance the dispersion level of clay in the matrix. In this study High Density Polyethylene (HDPE) and Linear Low Density Polyethylene (LLDPE) layered silicate nanocomposite were melt-compounded with two concentrations of organomodified clay (2 and 4 wt. %). The interaction between nanoclay, compatibilizer and rotomolding grade of PE were examined by using X-ray diffraction, transmission electron microscopy (TEM) and rheology test. Rheology was used to determine the performance of our material at low shear processing condition.

  9. Low-intermediate dose testosterone replacement therapy by different pharmaceutical preparations improves frailty score in elderly hypogonadal hyperglycaemic patients.

    PubMed

    Strollo, Felice; Strollo, Giovanna; Morè, Massimo; Magni, Paolo; Macchi, Chiara; Masini, Maria Angela; Carucci, Iarba; Celotti, Fabio; Ruscica, Massimiliano; Gentile, Sandro

    2013-06-01

    An open-label follow-up study of low-to-intermediate dose testosterone replacement therapy (TRT) was conducted in 64 overweight patients (aged 65-75 years) with late onset hypogonadism (LOH) and increased fasting plasma glucose (FPG). Patients were subdivided into four treatment groups: oral testosterone (T) (T undecanoate, 80 mg/d), transmucosal T (60 mg/d), transdermal T (30 mg/d) or no treatment (control), and evaluated at 0 and 6 months. FPG, hemoglobin (Hb), prostate-specific antigen (PSA) and total T were measured and the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) index was calculated. Body mass index (BMI), waist circumference, fitness level (6-min walking test), Aging Males' Symptoms (AMS) scale, handgrip strength and energy expenditure with physical activity (Minnesota questionnaire for Leisure Time Physical Activity (LTPA)) were evaluated and a "frailty score" (based on: grip strength, gait speed and LTPA) was calculated. T levels increased in all treatment groups; the oral T group had values still in the hypogonadal range (5.9 ± 1.1 nmol/L). PSA and Hb concentrations did not change in any group. BMI, waist circumference, FPG and HOMA-IR improved in all T-treated groups after 6 months, with a greater effect seen with transmucosal and transdermal T compared with oral T. This study indicates that low-to-intermediate dose TRT may be safely utilized in LOH patients to ameliorate somatic and psychological frailty symptoms in association with improved anthropometric and glycometabolic parameters in aging, overweight men with LOH and impaired fasting glucose. PMID:23517433

  10. Improvement of vehicle roll stability by varying suspension properties

    NASA Astrophysics Data System (ADS)

    Shim, Taehyun; Velusamy, Pradheep C.

    2011-02-01

    Vehicle roll dynamics are strongly influenced by suspension properties such as roll centre height, roll steer, and roll camber. In this paper, the effects of suspension properties on vehicle roll response have been investigated using a multi-body vehicle dynamics programme. Roll dynamics of a vehicle model with MacPherson (front) and multilink (rear) suspensions were evaluated for the fishhook manoeuvre and variations of its roll response due to changes in the suspension properties were assessed by quantitatively analysing the vehicle response through simulation. Critical suspension design parameters for vehicle roll dynamics were identified and adjusted to improve roll stability of the vehicle model with passive suspension. Design of experiments has been used for identifying critical hardpoints affecting the suspension parameters, and optimisation techniques were employed for parameter optimisation. This approach provides a viable alternative to costlier active control systems for economy-class vehicles.

  11. The surface layer of pharmaceutical compacts: the role of the punch surface and its impact on the mechanical properties of the compacts.

    PubMed

    Mazel, V; Busignies, V; Diarra, H; Reiche, I; Tchoreloff, P

    2013-02-14

    During pharmaceutical compaction, the interaction between the punch and the powder determines the formation and the aspect of the surface of the compact. In industry, the properties of the punch surface, which play a key role in this interaction, are sometimes changed by fixing an intermediate layer onto the punch to prevent sticking problems. In this article, the case of a polymer insert layer was studied. Firstly, sugar spheres were compacted with and without the polymer insert fixed onto the punches. After compaction with uncovered punches, the surface particles, which had been subjected to high deformation, were flattened on one side. However, it was observed, using confocal X-ray microfluorescence, that this kind of deformation was limited to the surface and that the bulk particles, which underwent a more isotropic deformation, still exhibited an approximately round shape. Secondly, the influence of the surface structure on the mechanical properties of the compacts was studied. The indentation hardness and the tensile strength of compacts of microcrystalline cellulose (MCC) and anhydrous calcium phosphate (aCP) were studied. No differences were found for the compacts of MCC produced with the two kinds of punches, but the compacts of aCP obtained with uncovered punches presented a higher hardness and a higher tensile strength than those obtained with covered punches.

  12. Petitioning the FDA to Improve Pharmaceutical, Device and Public Health Safety by Ordinary Citizens: A Descriptive Analysis

    PubMed Central

    Yang, Y. Tony; Cheng, Xi; Bian, John; Bennett, Charles L.

    2016-01-01

    The United States Constitution protects the right of citizens to petition the government for “a redress of grievances.” This right has important implications for citizens desiring to advance the public health by petitioning administrative agencies, such as the Food and Drug Administration, to take safety actions. We examined a total of 1,915 petitions filed between 2001 and 2013 to investigate the outcomes of citizen petitions that address public health concerns. We found that most petitions were filed by manufacturers against other manufacturers. Only 346 (18%) of all petitions were submitted by individuals and non-profit organizations, and 178 (87.3%) of these petitions with a final response were denied. On average, these petitions required 2.85 years for a final agency decision, and many decisions remain pending 10–13 years after their initial submission. The great majority of the approved requests included some form of risk communication, such as labeling changes, boxed warnings or placement of a drug into a Risk Evaluation and Mitigation Strategy. As a policy instrument to improve the safety of medical and food products, the citizen petition process requires sophisticated legal and scientific expertise, and may not represent a viable route for ordinary citizens to petition the FDA to “redress grievances.” PMID:27171162

  13. MULTIFUNCTIONAL AND STIMULI-SENSITIVE PHARMACEUTICAL NANOCARRIERS

    PubMed Central

    Torchilin, Vladimir

    2011-01-01

    Currently used pharmaceutical nanocarriers, such as liposomes, micelles, and polymeric nanoparticles, demonstrate a broad variety of useful properties, such as longevity in the body; specific targeting to certain disease sites; enhanced intracellular penetration; contrast properties allowing for direct carrier visualization in vivo; stimili-sensitivity, and others. Some of those pharmaceutical carriers have already made their way into clinic, while others are still under preclinical development. In certain cases, the pharmaceutical nanocarriers combine several of the listed properties. Long-circulating immunoliposomes capable of prolonged residence in the blood and specific target recognition represent one of examples of this kind. The engineering of multifunctional pharmaceutical nanocarriers combining several useful properties in one particle can significantly enhance the efficacy of many therapeutic and diagnostic protocols. This paper considers the current status and possible future directions in the emerging area of multifunctional nanocarriers with primary attention on the combination of such properties as longevity, targetability, intracellular penetration, contrast loading, and stimuli sensitivity. PMID:18977297

  14. Improvement of thymol properties by complexation with cyclodextrins: in vitro and in vivo studies.

    PubMed

    Nieddu, Maria; Rassu, Giovanna; Boatto, Gianpiero; Bosi, Paolo; Trevisi, Paolo; Giunchedi, Paolo; Carta, Antonio; Gavini, Elisabetta

    2014-02-15

    Thymol, an effective agent for microbial diseases, has a low aqueous solubility and a strong bitter/irritating taste. These physicochemical characteristics need to be improved to develop pharmaceutical preparations. This study evaluates whether β-cyclodextrin and a copolymer based on dimethylaminoethyl methacrylate (DMAEMA) interact with thymol in order to control powderization, solubilization, and taste-masking properties. The thymol-β-cyclodextrin complex was prepared by co-precipitation and sealed-heating methods. The DMAEMA copolymer was mixed with the complex using a new approach, instead of spray coating, to decrease thymol volatility. In vivo studies were performed. Sealed-heating is a suitable method for including thymol in β-cyclodextrin with a good loading efficiency; thymol volatility control is achieved by mixing the complex with the DMAEMA copolymer. β-Cyclodextrin accelerates the in vivo thymol absorption rate compared with the free drug; the thymol half-life is still long. Therefore, a low number of administrations per day are required. Although bioavailability is unchanged with respect to free thymol, high doses could be administered of a selected formulation without compromising the compliance. Furthermore, thymol that is not absorbed is held along the intestine, where it can useful in the treatment and/or prevention of intestinal bacterial diseases. PMID:24507296

  15. Optimization of the cyclotide framework to improve cell penetration properties

    PubMed Central

    Huang, Yen-Hua; Chaousis, Stephanie; Cheneval, Olivier; Craik, David J.; Henriques, Sónia T.

    2015-01-01

    Cell penetrating peptides have been regarded as promising vectors to deliver hydrophilic molecules inside cells. Although they are great tools for research and have high potential as drug delivery systems, their application as drugs is impaired by their low stability in serum. Cyclotides, cyclic disulfide-rich peptides from plants, are ultra-stable molecules that have inspired applications in drug design as they can be used as scaffolds to stabilize linear bioactive sequences. Recently, they have also been shown to possess cell-penetrating properties. The combination of their remarkable stability and cell-penetrating properties opens new avenues for the application of peptides to bind to and inhibit intracellular proteins. Nevertheless, for a broader application of these molecules as vectors is of utmost importance to improve their cellular internalization efficiency. In this study we successfully modified MCoTI-II, one of the most widely studied cyclotide scaffolds in drug design, and improved its internalization properties. The internalization of the newly designed MCoTI-II is as efficient as the gold standard cell-penetrating peptide (CPP) TAT and maintains all the required features as a template to graft desired bioactivities. PMID:25709580

  16. Optimization of the cyclotide framework to improve cell penetration properties.

    PubMed

    Huang, Yen-Hua; Chaousis, Stephanie; Cheneval, Olivier; Craik, David J; Henriques, Sónia T

    2015-01-01

    Cell penetrating peptides have been regarded as promising vectors to deliver hydrophilic molecules inside cells. Although they are great tools for research and have high potential as drug delivery systems, their application as drugs is impaired by their low stability in serum. Cyclotides, cyclic disulfide-rich peptides from plants, are ultra-stable molecules that have inspired applications in drug design as they can be used as scaffolds to stabilize linear bioactive sequences. Recently, they have also been shown to possess cell-penetrating properties. The combination of their remarkable stability and cell-penetrating properties opens new avenues for the application of peptides to bind to and inhibit intracellular proteins. Nevertheless, for a broader application of these molecules as vectors is of utmost importance to improve their cellular internalization efficiency. In this study we successfully modified MCoTI-II, one of the most widely studied cyclotide scaffolds in drug design, and improved its internalization properties. The internalization of the newly designed MCoTI-II is as efficient as the gold standard cell-penetrating peptide (CPP) TAT and maintains all the required features as a template to graft desired bioactivities. PMID:25709580

  17. Pharmaceutical properties of a low-substituted hydroxypropyl cellulose (L-HPC) hydrogel as a novel external dressing.

    PubMed

    Ogawa, Atsushi; Nakayama, Sachie; Uehara, Mami; Mori, Yasuhiro; Takahashi, Mai; Aiba, Tetsuya; Kurosaki, Yuji

    2014-12-30

    Controlling the moisture balance between exudates and their transpiration from the surface of wounded skin is important for healing. Low-substituted hydroxypropyl cellulose (L-HPC) hydrogel sheets (HGSs) possessing high water retention and water vapor transmission properties were prepared by neutralizing the highly viscous alkaline liquid of 7-10% L-HPC. Glycerol-impregnated L-HPC hydrogel sheets (L-HPC G-HGSs) were obtained by exchanging aqueous liquid in L-HPC HGSs. The physical characteristics required for wound dressings, i.e., mechanical strength, adhesive strength, and water retention properties, as well as the water vapor transmission (WVT) properties of L-HPC HGSs and L-HPC G-HGSs were evaluated. The mechanical strengths of L-HPC HGSs were enhanced with increases in the L-HPC content. The impregnation of glycerol in L-HPC HGSs yielded a significantly elasticated sheet. The adhesive strengths of L-HPC HGSs were significantly lower than those of commercial medical dressings. Water retention in L-HPC HGSs after being stored for 2h at 37°C was approximately 50%. The WVT rate of 7% L-HPC HGS was approximately 40g/m(2)/h, which was markedly higher than that of silicone gel type medical dressings. In conclusion, L-HPC HGSs are promising dressings that maintain an adequate moisture balance by transpiring excessive wound exudates with less damage to the healing wound.

  18. Improved properties of micronized genetically modified flax fibers.

    PubMed

    Dymińska, Lucyna; Szatkowski, Michał; Wróbel-Kwiatkowska, Magdalena; Zuk, Magdalena; Kurzawa, Adam; Syska, Wojciech; Gągor, Anna; Zawadzki, Mirosław; Ptak, Maciej; Mączka, Mirosław; Hanuza, Jerzy; Szopa, Jan

    2012-12-15

    The aim of this study was to investigate the effect of micronization on the compound content, crystalline structure and physicochemical properties of fiber from genetically modified (GM) flax. The GM flax was transformed with three bacterial (Ralstonia eutropha) genes coding for enzymes of polyhydroxybutyrate (PHB) synthesis and under the control of the vascular bundle promoter. The modification resulted in fibers containing the 3-hydroxybutyrate polymer bound to cellulose via hydrogen and ester bonds and antioxidant compounds (phenolic acids, vanillin, vitexin, etc.). The fibers appeared to have a significantly decreased particle size after 20h of ball-milling treatment. Micronized fibers showed reduced phenolic contents and antioxidant capacity compared to the results for untreated fibers. An increased level of PHB was also detected. Micronization introduces structural changes in fiber constituents (cellulose, hemicellulose, pectin, lignin, PHB) and micronized fibers exhibit more functional groups (hydroxyl, carboxyl) derived from those constituents. It is thus concluded that micronization treatments improve the functional properties of the fiber components.

  19. Micellar nanocarriers: pharmaceutical perspectives.

    PubMed

    Torchilin, V P

    2007-01-01

    Micelles, self-assembling nanosized colloidal particles with a hydrophobic core and hydrophilic shell are currently successfully used as pharmaceutical carriers for water-insoluble drugs and demonstrate a series of attractive properties as drug carriers. Among the micelle-forming compounds, amphiphilic copolymers, i.e., polymers consisting of hydrophobic block and hydrophilic block, are gaining an increasing attention. Polymeric micelles possess high stability both in vitro and in vivo and good biocompatibility, and can solubilize a broad variety of poorly soluble pharmaceuticals many of these drug-loaded micelles are currently at different stages of preclinical and clinical trials. Among polymeric micelles, a special group is formed by lipid-core micelles, i.e., micelles formed by conjugates of soluble copolymers with lipids (such as polyethylene glycol-phosphatidyl ethanolamine conjugate, PEG-PE). Polymeric micelles, including lipid-core micelles, carrying various reporter (contrast) groups may become the imaging agents of choice in different imaging modalities. All these micelles can also be used as targeted drug delivery systems. The targeting can be achieved via the enhanced permeability and retention (EPR) effect (into the areas with the compromised vasculature), by making micelles of stimuli-responsive amphiphilic block-copolymers, or by attaching specific targeting ligand molecules to the micelle surface. Immunomicelles prepared by coupling monoclonal antibody molecules to p-nitrophenylcarbonyl groups on the water-exposed termini of the micelle corona-forming blocks demonstrate high binding specificity and targetability. This review will discuss some recent trends in using micelles as pharmaceutical carriers. PMID:17109211

  20. Micro-scale measurement of the mechanical properties of compressed pharmaceutical powders. 1: The elasticity and fracture behavior of microcrystalline cellulose.

    PubMed

    Hancock, B C; Clas, S D; Christensen, K

    2000-11-19

    The feasibility of using very small compacts ( approximately 8.0 x 4.5 x 0.4 mm; approximately 20 mg) to determine the elasticity and fracture behavior of compressed pharmaceutical powders using the three-point beam-bending technique was evaluated. Compacts of microcrystalline cellulose with a range of porosities were tested using a thermomechanical analyzer and values for the Young's modulus and critical stress intensity factor at zero porosity (E(0) and K(IC0)) were determined by extrapolation. The value of E(0) measured at ambient relative humidity on un-notched beams was found to be in close agreement with that reported for much larger samples, and the value of K(IC0) for the small notched compacts was at the lower limit of the accepted range of values for microcrystalline cellulose. The fracture toughness (R) and total energy of fracture (U) for the notched specimens were also determined and used to estimate the apparent surface energies for crack initiation (gamma(i)) and for total fracture (gamma(f)). To further probe the utility of the micro-scale mechanical testing techniques, the effects of humidity on the various mechanical properties of the small microcrystalline compacts were examined and it was found that E(0), K(IC0), R(0), gamma(i0) and gamma(f0) each decreased as the surrounding humidity (and water content of the samples) increased.

  1. Investigation of the photoionization properties of pharmaceutically relevant substances by resonance-enhanced multiphoton ionization spectroscopy and single-photon ionization spectroscopy using synchrotron radiation.

    PubMed

    Kleeblatt, Juliane; Ehlert, Sven; Hölzer, Jasper; Sklorz, Martin; Rittgen, Jan; Baumgärtel, Peter; Schubert, Jochen K; Zimmermann, Ralf

    2013-08-01

    The photoionization properties of the pharmaceutically relevant substances amantadine, diazepam, dimethyltryptamine, etomidate, ketamine, mescaline, methadone, and propofol were determined. At beamline U125/2-10m-NIM of the BESSY II synchrotron facility (Berlin, Germany) vacuum ultraviolet (VUV) photoionization spectra were recorded in the energy range 7.1 to 11.9 eV (174.6 to 104.2 nm), showing the hitherto unknown ionization energies and fragmentation appearance energies of the compounds under investigation. Furthermore, (1+1)-resonance-enhanced multiphoton ionization (REMPI) spectra of selected compounds (amantadine, diazepam, etomidate, ketamine, and propofol) were recorded by a continuous scan in the energy range between 3.6 and 5.7 eV (345 to 218 nm) using a tunable optical parametric oscillator (spectral resolution: 0.1 nm) laser system. The resulting REMPI wavelength spectra of these compounds are discussed and put into context with already known UV absorption data. Time-of-flight mass spectrometry was used for ion detection in both experiments. Finally, the implications of the obtained physical-chemical results for potential analytical applications are discussed. In this context, fast detection approaches for the considered compounds from breath gas using photoionization mass spectrometry and a rapid pre-concentration step (e.g., needle trap device) are of interest.

  2. Improving satellite retrieved aerosol microphysical properties using GOCART data

    NASA Astrophysics Data System (ADS)

    Li, S.; Kahn, R.; Chin, M.; Garay, M. J.; Chen, L.; Liu, Y.

    2014-09-01

    The Multi-Angle Imaging Spectro-Radiometer (MISR) instrument on NASA's Terra satellite can provide more reliable Aerosol Optical Depth (AOD, τ) and more particle information, such as constraints on particle size (Angström exponent or ANG, α), particle shape, and single-scattering albedo (SSA, ω), than many other satellite instruments. However, MISR's ability to retrieve aerosol properties is weakened at low AOD levels. When aerosol-type information content is low, many candidate aerosol mixtures can match the observed radiances. We propose an algorithm to improve MISR aerosol retrievals by constraining MISR mixtures' ANG and absorbing AOD (AAOD) with Goddard Chemistry Aerosol Radiation and Transport (GOCART) model-simulated aerosol properties. To demonstrate this approach, we calculated MISR aerosol optical properties over the contiguous US from 2006 to 2009. Sensitivities associated with the thresholds of MISR-GOCART differences were analyzed according to the agreement between our results (AOD, ANG, and AAOD) and AErosol RObotic NETwork (AERONET) observations. Overall, our AOD has a good agreement with AERONET because the MISR AOD retrieval is not sensitive to different mixtures under many retrieval conditions. The correlation coefficient (r) between our ANG and AERONET improves to 0.45 from 0.29 for the MISR Version 22 standard product and 0.43 for GOCART when all data points are included. However, when only cases having AOD > 0.2, the MISR product itself has r ~ 0.40, and when only AOD > 0.2 and the best-fitting mixture are considered, r ~ 0.49. So as expected, the ANG improvement occurs primarily when the model constraint is applied in cases where the particle type information content of the MISR radiances is low. Regression analysis for AAOD shows that MISR Version 22 and GOCART misestimate AERONET by a ratio (mean retrieved AAOD to mean AERONET AAOD) of 0.5; our method improves this ratio to 0.74. Large discrepancies are found through an inter

  3. Improved Properties of Pb Based BLZT Ferroelectric Ceramics

    SciTech Connect

    Kumar, Parveen; Singh, Sangeeta; Juneja, J. K.; Raina, K. K.; Prakash, Chandra

    2011-11-22

    Present report is concerning with investigation of effect of different sintering profiles on Pb based BLZT ceramics. The material powder of selected composition (Ba{sub 0.795}La{sub 0.005}Pb{sub 0.20}Ti{sub 0.90}Zr{sub 0.10}O{sub 3}) was prepared by solid state reaction route and then powder was compacted in the form of circular discs. The discs were then sintered at different temperatures (1325 deg. C for 4h, 1325 deg. C for 15min+1200 deg. C for 4h). Improved dielectric and ferroelectric properties were observed for samples sintered at 1200 deg. C. Shifting in T{sub c} to higher temperature could be related to enhanced tetragonality, which was further confirmed by X-ray diffraction analysis. All these improvements evidences that there is less Pb loss in case of modified sintering profile.

  4. Nano hydroxyapatite-coated implants improve bone nanomechanical properties.

    PubMed

    Jimbo, R; Coelho, P G; Bryington, M; Baldassarri, M; Tovar, N; Currie, F; Hayashi, M; Janal, M N; Andersson, M; Ono, D; Vandeweghe, S; Wennerberg, A

    2012-12-01

    Nanostructure modification of dental implants has long been sought as a means to improve osseointegration through enhanced biomimicry of host structures. Several methods have been proposed and demonstrated for creating nanotopographic features; here we describe a nanoscale hydroxyapatite (HA)-coated implant surface and hypothesize that it will hasten osseointegration and improve its quality relative to that of non-coated implants. Twenty threaded titanium alloy implants, half prepared with a stable HA nanoparticle surface and half grit-blasted, acid-etched, and heat-treated (HT), were inserted into rabbit femurs. Pre-operatively, the implants were morphologically and topographically characterized. After 3 weeks of healing, the samples were retrieved for histomorphometry. The nanomechanical properties of the surrounding bone were evaluated by nanoindentation. While both implants revealed similar bone-to-implant contact, the nanoindentation demonstrated that the tissue quality was significantly enhanced around the HA-coated implants, validating the postulated hypothesis.

  5. Novel pharmaceuticals in the management of postoperative pain.

    PubMed

    Palmer, Pamela

    2015-01-01

    Novel pharmaceutical advances in postoperative pain management include both non-opioid adjuvants as well as opioid analgesics. Optimizing postoperative analgesics includes improving onset of action, matching duration of analgesia to the setting of use, and minimizing adverse events. To improve on the current standard of care, the physicochemical properties of new analgesics and route of administration must be taken into consideration in order to achieve these three goals. Appropriately, patient satisfaction with postoperative pain is a key emphasis in hospital-focused patient satisfaction surveys, thereby focusing much-needed attention on improvement of care in the postoperative setting from both an analgesic efficacy and safety standpoint.

  6. [Application of microwave irradiation technology to the field of pharmaceutics].

    PubMed

    Zhang, Xue-Bing; Shi, Nian-Qiu; Yang, Zhi-Qiang; Wang, Xing-Lin

    2014-03-01

    Microwaves can be directly transformed into heat inside materials because of their ability of penetrating into any substance. The degree that materials are heated depends on their dielectric properties. Materials with high dielectric loss are more easily to reach a resonant state by microwaves field, then microwaves can be absorbed efficiently. Microwave irradiation technique with the unique heating mechanisms could induce drug-polymer interaction and change the properties of dissolution. Many benefits such as improving product quality, increasing energy efficiency and reducing times can be obtained by microwaves. This paper summarized characteristics of the microwave irradiation technique, new preparation techniques and formulation process in pharmaceutical industry by microwave irradiation technology. The microwave technology provides a new clue for heating and drying in the field of pharmaceutics.

  7. Reprint of "Characterisation and modelling of the thermorheological properties of pharmaceutical polymers and their blends using capillary rheometry: Implications for hot melt processing of dosage forms".

    PubMed

    Jones, David S; Margetson, Daniel N; McAllister, Mark S; Andrews, Gavin P

    2015-12-30

    Given the growing interest in thermal processing methods, this study describes the use of an advanced rheological technique, capillary rheometry, to accurately determine the thermorheological properties of two pharmaceutical polymers, Eudragit E100 (E100) and hydroxypropylcellulose JF (HPC) and their blends, both in the presence and absence of a model therapeutic agent (quinine, as the base and hydrochloride salt). Furthermore, the glass transition temperatures (Tg) of the cooled extrudates produced using capillary rheometry were characterised using Dynamic Mechanical Thermal Analysis (DMTA) thereby enabling correlations to be drawn between the information derived from capillary rheometry and the glass transition properties of the extrudates. The shear viscosities of E100 and HPC (and their blends) decreased as functions of increasing temperature and shear rates, with the shear viscosity of E100 being significantly greater than that of HPC at all temperatures and shear rates. All platforms were readily processed at shear rates relevant to extrusion (approximately 200-300s(-1)) and injection moulding (approximately 900s(-1)). Quinine base was observed to lower the shear viscosities of E100 and E100/HPC blends during processing and the Tg of extrudates, indicative of plasticisation at processing temperatures and when cooled (i.e. in the solid state). Quinine hydrochloride (20% w/w) increased the shear viscosities of E100 and HPC and their blends during processing and did not affect the Tg of the parent polymer. However, the shear viscosities of these systems were not prohibitive to processing at shear rates relevant to extrusion and injection moulding. As the ratio of E100:HPC increased within the polymer blends the effects of quinine base on the lowering of both shear viscosity and Tg of the polymer blends increased, reflecting the greater solubility of quinine within E100. In conclusion, this study has highlighted the importance of capillary rheometry in

  8. Characterisation and modelling of the thermorheological properties of pharmaceutical polymers and their blends using capillary rheometry: Implications for hot melt processing of dosage forms.

    PubMed

    Jones, David S; Margetson, Daniel N; McAllister, Mark S; Andrews, Gavin P

    2015-09-30

    Given the growing interest in thermal processing methods, this study describes the use of an advanced rheological technique, capillary rheometry, to accurately determine the thermorheological properties of two pharmaceutical polymers, Eudragit E100 (E100) and hydroxypropylcellulose JF (HPC) and their blends, both in the presence and absence of a model therapeutic agent (quinine, as the base and hydrochloride salt). Furthermore, the glass transition temperatures (Tg) of the cooled extrudates produced using capillary rheometry were characterised using Dynamic Mechanical Thermal Analysis (DMTA) thereby enabling correlations to be drawn between the information derived from capillary rheometry and the glass transition properties of the extrudates. The shear viscosities of E100 and HPC (and their blends) decreased as functions of increasing temperature and shear rates, with the shear viscosity of E100 being significantly greater than that of HPC at all temperatures and shear rates. All platforms were readily processed at shear rates relevant to extrusion (approximately 200-300 s(-1)) and injection moulding (approximately 900 s(-1)). Quinine base was observed to lower the shear viscosities of E100 and E100/HPC blends during processing and the Tg of extrudates, indicative of plasticisation at processing temperatures and when cooled (i.e. in the solid state). Quinine hydrochloride (20% w/w) increased the shear viscosities of E100 and HPC and their blends during processing and did not affect the Tg of the parent polymer. However, the shear viscosities of these systems were not prohibitive to processing at shear rates relevant to extrusion and injection moulding. As the ratio of E100:HPC increased within the polymer blends the effects of quinine base on the lowering of both shear viscosity and Tg of the polymer blends increased, reflecting the greater solubility of quinine within E100. In conclusion, this study has highlighted the importance of capillary rheometry in

  9. Targeting the Biophysical Properties of the Myeloma Initiating Cell Niches: A Pharmaceutical Synergism Analysis Using Multi-Scale Agent-Based Modeling

    PubMed Central

    Su, Jing; Zhang, Le; Zhang, Wen; Choi, Dong Song; Wen, Jianguo; Jiang, Beini; Chang, Chung-Che; Zhou, Xiaobo

    2014-01-01

    Multiple myeloma, the second most common hematological cancer, is currently incurable due to refractory disease relapse and development of multiple drug resistance. We and others recently established the biophysical model that myeloma initiating (stem) cells (MICs) trigger the stiffening of their niches via SDF-1/CXCR4 paracrine; The stiffened niches then promote the colonogenesis of MICs and protect them from drug treatment. In this work we examined in silico the pharmaceutical potential of targeting MIC niche stiffness to facilitate cytotoxic chemotherapies. We first established a multi-scale agent-based model using the Markov Chain Monte Carlo approach to recapitulate the niche stiffness centric, pro-oncogenetic positive feedback loop between MICs and myeloma-associated bone marrow stromal cells (MBMSCs), and investigated the effects of such intercellular chemo-physical communications on myeloma development. Then we used AMD3100 (to interrupt the interactions between MICs and their stroma) and Bortezomib (a recently developed novel therapeutic agent) as representative drugs to examine if the biophysical properties of myeloma niches are drugable. Results showed that our model recaptured the key experimental observation that the MBMSCs were more sensitive to SDF-1 secreted by MICs, and provided stiffer niches for these initiating cells and promoted their proliferation and drug resistance. Drug synergism analysis suggested that AMD3100 treatment undermined the capability of MICs to modulate the bone marrow microenvironment, and thus re-sensitized myeloma to Bortezomib treatments. This work is also the first attempt to virtually visualize in 3D the dynamics of the bone marrow stiffness during myeloma development. In summary, we established a multi-scale model to facilitate the translation of the niche-stiffness centric myeloma model as well as experimental observations to possible clinical applications. We concluded that targeting the biophysical properties of stem

  10. Improving drug candidates by design: a focus on physicochemical properties as a means of improving compound disposition and safety.

    PubMed

    Meanwell, Nicholas A

    2011-09-19

    The development of small molecule drug candidates from the discovery phase to a marketed product continues to be a challenging enterprise with very low success rates that have fostered the perception of poor productivity by the pharmaceutical industry. Although there have been significant advances in preclinical profiling that have improved compound triaging and altered the underlying reasons for compound attrition, the failure rates have not appreciably changed. As part of an effort to more deeply understand the reasons for candidate failure, there has been considerable interest in analyzing the physicochemical properties of marketed drugs for the purpose of comparing with drugs in discovery and development as a means capturing recent trends in drug design. The scenario that has emerged is one in which contemporary drug discovery is thought to be focused too heavily on advancing candidates with profiles that are most easily satisfied by molecules with increased molecular weight and higher overall lipophilicity. The preponderance of molecules expressing these properties is frequently a function of increased aromatic ring count when compared with that of the drugs launched in the latter half of the 20th century and may reflect a preoccupation with maximizing target affinity rather than taking a more holistic approach to drug design. These attributes not only present challenges for formulation and absorption but also may influence the manifestation of toxicity during development. By providing some definition around the optimal physicochemical properties associated with marketed drugs, guidelines for drug design have been developed that are based largely on calculated parameters and which may readily be applied by medicinal chemists as an aid to understanding candidate quality. The physicochemical properties of a molecule that are consistent with the potential for good oral absorption were initially defined by Lipinski, with additional insights allowing further

  11. Improvement of thermoelectric properties of alkaline-earth hexaborides

    SciTech Connect

    Takeda, Masatoshi . E-mail: takeda@mech.nagaokaut.ac.jp; Terui, Manabu; Takahashi, Norihito; Ueda, Noriyoshi

    2006-09-15

    Thermoelectric (TE) and transport properties of alkaline-earth hexaborides were examined to investigate the possibility of improvement in their TE performance. As carrier concentration increased, electrical conductivity increased and the absolute value of the Seebeck coefficient decreased monotonically, while carrier mobility was almost unchanged. These results suggest that the electrical properties of the hexaboride depend largely on carrier concentration. Thermal conductivity of the hexaboride was higher than 10 W/m K even at 1073 K, which is relatively high among TE materials. Alloys of CaB{sub 6} and SrB{sub 6} were prepared in order to reduce lattice thermal conductivity. Whereas the Seebeck coefficient and electrical conductivity of the alloys were intermediate between those of CaB{sub 6} and SrB{sub 6} single phases, the thermal conductivities of the alloys were lower than those of both single phases. The highest TE performance was obtained in the vicinity of Ca{sub 0.5}Sr{sub 0.5}B{sub 6}, indicating that alloying is effective in improving the performance. - Graphical abstract: Thermoelectric figure-of-merit, ZT, for (Ca,Sr)B{sub 6} alloys. The highest ZT value of 0.35 at 1073 K was obtained due to effective reduction of thermal conductivity by alloying.

  12. Phosphonic Acid-Functionalized Polyurethane Dispersions with Improved Adhesion Properties.

    PubMed

    Breucker, Laura; Landfester, Katharina; Taden, Andreas

    2015-11-11

    A facile route to phosphorus-functionalized polyurethane dispersions (P-PUDs) with improved adhesion properties is presented. (Bis)phosphonic acid moieties serve as adhesion promoting sites that are covalently attached via an end-capping reaction to isocyanate-reactive polyurethane particles under aqueous conditions. The synthetic approach circumvents solubility issues, offers great flexibility in terms of polyurethane composition, and allows for the synthesis of semicrystalline systems with thermomechanical response due to reversible physical cross-linking. Differential scanning calorimetry (DSC) is used to investigate the effect of functionalization on the semicrystallinity. The end-capping conversion was determined via inductively-coupled plasma optical emission spectroscopy (ICP-OES) and was surprisingly found to be almost independent of the stoichiometry of reaction, suggesting an adsorption-dominated process. Particle charge detection (PCD) experiments reveal that a dense surface coverage of phosphonic acid groups can be attained and that, at high functionalization degrees, the phosphonic adhesion moieties are partially dragged inside the colloidal P-PUD particle. Quartz crystal microbalance with dissipation (QCMD) investigations conducted with hydroxyapatite (HAP) and stainless steel sensors as model surfaces show a greatly enhanced affinity of the aqueous P-PUDs and furthermore indicate polymer chain rearrangements and autonomous film formation under wet conditions. Due to their facile synthesis, significantly improved adhesion, and variable film properties, P-PUD systems such as the one described here are believed to be of great interest for multiple applications, e.g., adhesives, paints, anticorrosion, or dentistry. PMID:26491881

  13. Modified β-Cyclodextrin Inclusion Complex to Improve the Physicochemical Properties of Albendazole. Complete In Vitro Evaluation and Characterization

    PubMed Central

    García, Agustina; Leonardi, Darío; Salazar, Mario Oscar; Lamas, María Celina

    2014-01-01

    The potential use of natural cyclodextrins and their synthetic derivatives have been studied extensively in pharmaceutical research and development to modify certain properties of hydrophobic drugs. The ability of these host molecules of including guest molecules within their cavities improves notably the physicochemical properties of poorly soluble drugs, such as albendazole, the first chosen drug to treat gastrointestinal helminthic infections. Thus, the aim of this work was to synthesize a beta cyclodextrin citrate derivative, to analyze its ability to form complexes with albendazole and to evaluate its solubility and dissolution rate. The synthesis progress of the cyclodextrin derivative was followed by electrospray mass spectrometry and the acid-base titration of the product. The derivative exhibited an important drug affinity. Nuclear magnetic resonance experiments demonstrated that the tail and the aromatic ring of the drug were inside the cavity of the cyclodextrin derivative. The inclusion complex was prepared by spray drying and full characterized. The drug dissolution rate displayed exceptional results, achieving 100% drug release after 20 minutes. The studies indicated that the inclusion complex with the cyclodextrin derivative improved remarkably the physicochemical properties of albendazole, being a suitable excipient to design oral dosage forms. PMID:24551084

  14. Improving satellite-retrieved aerosol microphysical properties using GOCART data

    NASA Astrophysics Data System (ADS)

    Li, S.; Kahn, R.; Chin, M.; Garay, M. J.; Liu, Y.

    2015-03-01

    The Multi-angle Imaging SpectroRadiometer (MISR) aboard the NASA Earth Observing System's Terra satellite can provide more reliable aerosol optical depth (AOD) and better constraints on particle size (Ångström exponent, or ANG), sphericity, and single-scattering albedo (SSA) than many other satellite instruments. However, many aerosol mixtures pass the algorithm acceptance criteria, yielding a poor constraint, when the particle-type information in the MISR radiances is low, typically at low AOD. We investigate adding value to the MISR aerosol product under these conditions by filtering the list of MISR-retrieved mixtures based on agreement between the mixture ANG and absorbing AOD (AAOD) values, and simulated aerosol properties from the Goddard Chemistry Aerosol Radiation and Transport (GOCART) model. MISR-GOCART ANG difference and AAOD ratio thresholds for applying GOCART constraints were determined based on coincident AOD, ANG, and AAOD measurements from the AErosol RObotic NETwork (AERONET). The results were validated by comparing the adjusted MISR aerosol optical properties over the contiguous USA between 2006 and 2009 with additional AERONET data. The correlation coefficient (r) between the adjusted MISR ANG derived from this study and AERONET improves to 0.45, compared to 0.29 for the MISR Version 22 standard product. The ratio of the adjusted MISR AAOD to AERONET increases to 0.74, compared to 0.5 for the MISR operational retrieval. These improvements occur primarily when AOD < 0.2 for ANG and AOD < 0.5 for AAOD. Spatial and temporal differences among the aerosol optical properties of MISR V22, GOCART, and the adjusted MISR are traced to (1) GOCART underestimation of AOD and ANG in polluted regions; (2) aerosol mixtures lacking in the MISR Version 22 algorithm climatology; (3) low MISR sensitivity to particle type under some conditions; and (4) parameters and thresholds used in our method.

  15. Synthesis and evaluation of the structural and physicochemical properties of carboxymethyl pregelatinized starch as a pharmaceutical excipient

    PubMed Central

    Lefnaoui, Sonia; Moulai-Mostefa, Nadji

    2015-01-01

    A pregelatinized starch (PGS) was derivatized with sodium chloroacetate (SCA) in alcoholic medium under alkaline condition to produce carboxymethyl pregelatinized starch (CMPGS) with various degrees of substitution (DS). Influence of the molar ratio of SCA to the glucopyranose units (SCA/GU), reaction time, temperature and the amount of sodium hydroxide on the degree of substitution (DS) and the reaction efficiency (RE) was studied. An optimal concentration of 30% of NaOH, for a reaction time of 1 h at 50 °C and molar ratio (SCA/GU) equal to 1.0, yielded an optimal DS of 0.55 and a RE of 55%. SEM micrographs revealed that the carboxymethylation assigned the structural arrangement of CMPGS and caused the granular disintegration. Wide angle diffraction X-ray (XRD) showed that the crystallinity of starch was obviously varied after carboxymethylation. New bands in FTIR spectra at 1417 and 1603 cm−1 indicated the presence of carboxymethyl groups. The solubility and viscosity of CMPGS increased with an increase in the degree of modification. In order to investigate the influence of DS on physical and drug release properties, CMPGS obtained with DS in the range of 0.12–0.55 was evaluated as tablet excipient for sustained drug release. Dissolution tests performed in phosphate buffer (pH 6.8), with Ibuprofen as drug model (25% loading) showed that CMPGS seems suitable to be used as sustained release excipient since the drug release was driven over a period up to 8 h. The in vitro release kinetics studies revealed that all formulations fit well with Korsmeyer-Peppas model and the mechanism of drug release is non-Fickian diffusion. PMID:26702266

  16. Improvement in properties of plastic teeth by electron beam irradiation

    NASA Astrophysics Data System (ADS)

    Sano, Yuko; Ishikawa, Shun-ichi; Seguchi, Tadao

    2011-11-01

    Improvement of the comfort and esthetics of artificial plastic teeth is desirable for the recently increasing numbers of elderly in society. Plastic teeth made of polycarbonate (PC) were modified by electron beam (EB) irradiation under specific conditions, and the change in the chemical properties of the PC was investigated. The water absorption, glucose attachment, level of bis-phenol-A (BPA) extraction, maltose adhesion, and mucin adhesion on the PC teeth were measured before and after EB irradiation. EB irradiation to a dose of 3.5 kGy at 150 °C in a nitrogen gas atmosphere reduced the water absorption by 20%, glucose absorption by 40%, maltose adhesion by 20%, and the amount of various amino acids, formed as the hydrolysis products of mucin, adhering on the PC teeth were reduced by 60-99%. The BPA content was lower than the detection limit for analysis of both the original and the EB irradiated PC teeth.

  17. Improving properties of Mg with Al–Cu additions

    SciTech Connect

    Rashad, Muhammad; Pan, Fusheng; Asif, Muhammad; Hussain, Shahid; Saleem, Muhammad

    2014-09-15

    The present work reports improvement in tensile properties of the Mg matrix reinforced with micron-sized copper–aluminum particulate hybrids. The Al–Cu particulate hybrids were incorporated into the Mg matrix through powder metallurgy method. The synthesized alloys exhibited homogeneously dispersed Mg{sub 2}Cu particles in the matrix, therefore leading to a 110% increase in yield strength (221 MPa) and a 72% enhancement in ultimate tensile strength (284 MPa) by addition of 1.0 wt.%Al–0.6 wt.%Cu particle hybrids. Optical microscopy, scanning election microscopy, transmission electron microscopy and X-ray diffraction were used to investigate the microstructure and intermetallic phases of the synthesized alloys. - Highlights: • Mg matrix is reinforced with Al–Cu particulate hybrids. • Powder metallurgic method is used to fabricate the alloys. • Tensile strength and ductility were increased simultaneously.

  18. Montmorillonite-levan nanocomposites with improved thermal and mechanical properties.

    PubMed

    Chen, Xiaoming; Gao, Hongsheng; Ploehn, Harry J

    2014-01-30

    This work reports on the structure and properties of novel nanocomposites composed of exfoliated montmorillonite clay blended with levan, a polysaccharide produced by Bacillus sp. Dry levan is very brittle, making it difficult to obtain stand-alone films. MMT-levan composites were prepared by solution blending in water, coating on plastic surfaces, partial drying at 50°C, and conditioning in air at 50-60% relative humidity. This process results in freestanding, transparent, and flexible films of pure levan and MMT-levan composites plasticized by 10-15 wt% water. XRD patterns from levan-MMT composites indicate an MMT interlayer spacing 0.62 nm greater than that of the starting MMT, suggesting re-stacking of MMT platelets coated by adsorbed, uncoiled levan molecules. FTIR results suggest that levan adheres to MMT via water-mediated hydrogen bonding between the levan's hydroxyl groups and MMT surface oxygens. MMT-levan composites have improved thermal stability and a well-defined glass transition temperature that increases with MMT loading. The tensile moduli of levan-MMT composites increase by as much as 480% relative to pure levan. The XRD and mechanical property results suggest that MMT reinforces levan through a filler network structure composed of MMT platelets bridged by adsorbed levan molecules, enhanced when the MMT loading becomes high enough (5-10wt% MMT) to induce an isotropic-nematic transition in MMT platelet orientation. PMID:24299812

  19. Stealth Properties to Improve Therapeutic Efficacy of Drug Nanocarriers

    PubMed Central

    Caliceti, Paolo

    2013-01-01

    Over the last few decades, nanocarriers for drug delivery have emerged as powerful tools with unquestionable potential to improve the therapeutic efficacy of anticancer drugs. Many colloidal drug delivery systems are underdevelopment to ameliorate the site specificity of drug action and reduce the systemic side effects. By virtue of their small size they can be injected intravenously and disposed into the target tissues where they release the drug. Nanocarriers interact massively with the surrounding environment, namely, endothelium vessels as well as cells and blood proteins. Consequently, they are rapidly removed from the circulation mostly by the mononuclear phagocyte system. In order to endow nanosystems with long circulation properties, new technologies aimed at the surface modification of their physicochemical features have been developed. In particular, stealth nanocarriers can be obtained by polymeric coating. In this paper, the basic concept underlining the “stealth” properties of drug nanocarriers, the parameters influencing the polymer coating performance in terms of opsonins/macrophages interaction with the colloid surface, the most commonly used materials for the coating process and the outcomes of this peculiar procedure are thoroughly discussed. PMID:23533769

  20. Ni-Flash-Coated Galvannealed Steel Sheet with Improved Properties

    NASA Astrophysics Data System (ADS)

    Pradhan, D.; Dutta, M.; Venugopalan, T.

    2016-09-01

    In the last several years, automobile industries have increasingly focused on galvannealed (GA) steel sheet due to their superior properties such as weldability, paintability and corrosion protection. To improve the properties further, different coatings on GA have been reported. In this context, an electroplating process (flash coating) of bright and adherent Ni plating was developed on GA steel sheet for covering the GA defects and enhancing the performances such as weldability, frictional behavior, corrosion resistance and phosphatability. For better illustration, a comparative study with bare GA steel sheet has also been carried out. The maximum electroplating current density of 700 A/m2 yielded higher cathode current efficiency of 95-98%. The performances showed that Ni-coated (coating time 5-7 s) GA steel sheet has better spot weldability, lower dynamic coefficient of friction (0.07 in lubrication) and three times more corrosion resistance compared to bare GA steel sheet. Plate-like crystal of phosphate coating with size of 10-25 µm was obtained on the Ni-coated GA. The main phase in the phosphate compound was identified as hopeite (63.4 wt.%) along with other phases such as spencerite (28.3 wt.%) and phosphophyllite (8.3 wt.%).

  1. Pharmaceutical applications of hot-melt extrusion: part I.

    PubMed

    Crowley, Michael M; Zhang, Feng; Repka, Michael A; Thumma, Sridhar; Upadhye, Sampada B; Battu, Sunil Kumar; McGinity, James W; Martin, Charles

    2007-09-01

    Interest in hot-melt extrusion techniques for pharmaceutical applications is growing rapidly with well over 100 papers published in the pharmaceutical scientific literature in the last 12 years. Hot-melt extrusion (HME) has been a widely applied technique in the plastics industry and has been demonstrated recently to be a viable method to prepare several types of dosage forms and drug delivery systems. Hot-melt extruded dosage forms are complex mixtures of active medicaments, functional excipients, and processing aids. HME also offers several advantages over traditional pharmaceutical processing techniques including the absence of solvents, few processing steps, continuous operation, and the possibility of the formation of solid dispersions and improved bioavailability. This article, Part I, reviews the pharmaceutical applications of hot-melt extrusion, including equipment, principles of operation, and process technology. The raw materials processed using this technique are also detailed and the physicochemical properties of the resultant dosage forms are described. Part II of this review will focus on various applications of HME in drug delivery such as granules, pellets, immediate and modified release tablets, transmucosal and transdermal systems, and implants.

  2. Mimicking mussel adhesion to improve interfacial properties in composites.

    PubMed

    Hamming, L M; Fan, X W; Messersmith, P B; Brinson, L C

    2008-07-01

    The macroscale properties of polymer-matrix composites depend immensely on the quality of the interaction between the reinforcement phase and the bulk polymer. This work presents a method to improve the interfacial adhesion between metal-oxides and a polymer matrix by performing surface-initiated polymerization (SIP) by way of a biomimetic initiator. The initiator was modeled after 3,4-dihydroxy-L-phenylalanine (dopa), an amino acid that is highly concentrated in mussel foot adhesive proteins. Mechanical pull out tests of NiTi and Ti-6Al-4V wires from poly (methyl methacrylate) (PMMA) were performed to directly test the interfacial adhesion. These tests demonstrated improvements in maximum interfacial shear stress of 116% for SIP-modified NiTi wires and 60% for SIP-modified Ti-6Al-4V wires over unmodified specimens. Polymer chain growth from the metal oxides was validated using x-ray photoemission spectroscopy (XPS), ellipsometry, scanning electron microscopy (SEM), and contact angle analysis. PMID:19578545

  3. Wet-preserved hemp fibreboard properties improvement with veneering

    NASA Astrophysics Data System (ADS)

    Kirilovs, E.; Kukle, S.; Gusovius, H.-J.

    2015-03-01

    The initial research describes a new type of fiber boards for the furniture interior design, developed in cooperation with ATB (Leibniz-Institute for Agricultural Engineering) by using a new method of raw materials preparation and specific production technologies of ATB. The main raw materials are aerobically aged hemp stalks. The samples are made of hemp chips with a long preservation time and fastened together with the UF glue. Specimens are 8 mm thick and correspond to a medium-density fiberboard, fitting standard EN622. Due to the fact that non-veneered material can be used only in non-load-bearing constructions, material improving technologies were studied, such as increase of board density, increase of glue percentage, partially substitution of wet-preserved hemp chips with a dry hemp and/or wooden chips to equalize moisture content of obtained mixture. The particular article describes how the new material is veneered with the oak veneer obtaining three-ply composite board with the improved mechanical properties that allows to use these boards in a load-bearing constructions. Tests are performed with the veneered material to determine such parameters as static bending strength (MOR), modulus of elasticity in static bending (MOE), swelling in thickness and hardness.

  4. Electron microscopy of pharmaceutical systems.

    PubMed

    Klang, Victoria; Valenta, Claudia; Matsko, Nadejda B

    2013-01-01

    During the last decades, the focus of research in pharmaceutical technology has steadily shifted towards the development and optimisation of nano-scale drug delivery systems. As a result, electron microscopic methods are increasingly employed for the characterisation of pharmaceutical systems such as nanoparticles and microparticles, nanoemulsions, microemulsions, solid lipid nanoparticles, different types of vesicles, nanofibres and many more. Knowledge of the basic properties of these systems is essential for an adequate microscopic analysis. Classical transmission and scanning electron microscopic techniques frequently have to be adapted for an accurate analysis of formulation morphology, especially in case of hydrated colloidal systems. Specific techniques such as environmental scanning microscopy or cryo preparation are required for their investigation. Analytical electron microscopic techniques such as electron energy-loss spectroscopy or energy-dispersive X-ray spectroscopy are additional assets to determine the elemental composition of the systems, but are not yet standard tools in pharmaceutical research. This review provides an overview of pharmaceutical systems of interest in current research and strategies for their successful electron microscopic analysis. Advantages and limitations of the different methodological approaches are discussed and recent findings of interest are presented. PMID:22921788

  5. The World Bank and pharmaceuticals.

    PubMed

    Falkenberg, T; Tomson, G

    2000-03-01

    Within less than a decade the World Bank has become the largest single source of finance (loans) for health in low and middle income countries as well as a major player in the field of pharmaceuticals. Often 20-50% of the recurrent government health budget in developing countries is used to procure drugs. Drugs are among the most salient and cost-effective elements of health care and often a key factor for the success of a health sector reform. However, pharmaceuticals are frequently being used irrationally, mainly due to market imperfections in health care, such as information asymmetries, leading to serious health problems and a heavy financial burden on the health system. Lending priorities set by the World Bank could be used to promote public health sector reform, leading to the rational use of affordable and available drugs of good quality in developing countries. This report provides the first analysis of World Bank activity in the pharmaceutical sector worldwide. The analysis of 77 staff appraisal reports, describing the planning phase of World Bank country projects, shows that 16% of the total World Bank health, nutrition and population budget, or approximately US$1.3 billion, has been committed to loans or credits supporting pharmaceutical activities in the programme countries between 1989-95. Roughly US$1.05 billion has been committed to procurement of drugs and medical equipment. Only 5% of the total pharmaceutical sector lending is committed to software components such as drug policy work and rational use of drugs. No more than 45% of the projects were developed in collaboration with pharmaceutical expertise. The World Bank is recommended to improve its pharmaceutical sector involvement by promoting drug policy research and development including national and international dialogue on pharmaceutical issues to ensure rational use of both drugs and loans. In this, the World Bank has an advantage given its experience from working with both the private and

  6. The World Bank and pharmaceuticals.

    PubMed

    Falkenberg, T; Tomson, G

    2000-03-01

    Within less than a decade the World Bank has become the largest single source of finance (loans) for health in low and middle income countries as well as a major player in the field of pharmaceuticals. Often 20-50% of the recurrent government health budget in developing countries is used to procure drugs. Drugs are among the most salient and cost-effective elements of health care and often a key factor for the success of a health sector reform. However, pharmaceuticals are frequently being used irrationally, mainly due to market imperfections in health care, such as information asymmetries, leading to serious health problems and a heavy financial burden on the health system. Lending priorities set by the World Bank could be used to promote public health sector reform, leading to the rational use of affordable and available drugs of good quality in developing countries. This report provides the first analysis of World Bank activity in the pharmaceutical sector worldwide. The analysis of 77 staff appraisal reports, describing the planning phase of World Bank country projects, shows that 16% of the total World Bank health, nutrition and population budget, or approximately US$1.3 billion, has been committed to loans or credits supporting pharmaceutical activities in the programme countries between 1989-95. Roughly US$1.05 billion has been committed to procurement of drugs and medical equipment. Only 5% of the total pharmaceutical sector lending is committed to software components such as drug policy work and rational use of drugs. No more than 45% of the projects were developed in collaboration with pharmaceutical expertise. The World Bank is recommended to improve its pharmaceutical sector involvement by promoting drug policy research and development including national and international dialogue on pharmaceutical issues to ensure rational use of both drugs and loans. In this, the World Bank has an advantage given its experience from working with both the private and

  7. Improvement of the soy formate dehydrogenase properties by rational design.

    PubMed

    Kargov, I S; Kleimenov, S Y; Savin, S S; Tishkov, V I; Alekseeva, A A

    2015-06-01

    Previous experiments on substitution of the residue Phe290 to Asp, Asn and Ser in NAD(+)-dependent formate dehydrogenase from soya Glycine max (SoyFDH) showed important role of the residue in enzyme thermal stability and catalytic properties (Alekseeva et al. Prot. Eng. Des. Sel., 2012a; 25: :781-88). In this work, we continued site-directed mutagenesis experiments of the Phe290 and the residue was changed to Ala, Thr, Tyr, Glu and Gln. All amino acid changes resulted in increase of catalytic constant from 2.9 to 3.5-4.7 s(-1). The substitution Phe290Ala led to KM (NAD+) decrease from 13.3 to 8.6 μM, and substitutions Phe290Tyr and Phe290Glu resulted in decrease and increase of KM (HCOO-) from 1.5 to 0.9 and -2.9 mM, respectively. The highest improvement of catalytic properties was observed for SoyFDH Phe290Ala which showed 2-fold higher catalytic efficiency with both substrates. Stability of mutants was examined by study of thermal inactivation kinetics and differential scanning calorimetry (DSC). All five amino acids provided increase of thermal stability of mutant SoyFDH in comparison with wild-type enzyme. Mutant SoyFDH Phe290Glu showed the highest improvement-the stabilization effect was 43 at 56°C. The DSC data agree with results of thermal inactivation kinetics. Substitutions Phe290Tyr, Phe290Thr, Phe290Gln and Phe290Glu provided Tm value increase 0.6°-6.6°. SoyFDH Phe290Glu and previously prepared SoyFDH Phe290Asp show similar thermal stability as enzymes from Candida boidinii and Mycobacterium vaccae N10 and have higher catalytic efficiency with NAD(+) compared with all described FDHs. Therefore, these mutants are very perspective enzymes for coenzyme regeneration in processes of chiral synthesis with dehydrogenases.

  8. Pharmaceutical care in smoking cessation.

    PubMed

    Marín Armero, Alicia; Calleja Hernandez, Miguel A; Perez-Vicente, Sabina; Martinez-Martinez, Fernando

    2015-01-01

    As a determining factor in various diseases and the leading known cause of preventable mortality and morbidity, tobacco use is the number one public health problem in developed countries. Facing this health problem requires authorities and health professionals to promote, via specific programs, health campaigns that improve patients' access to smoking cessation services. Pharmaceutical care has a number of specific characteristics that enable the pharmacist, as a health professional, to play an active role in dealing with smoking and deliver positive smoking cessation interventions. The objectives of the study were to assess the efficacy of a smoking cessation campaign carried out at a pharmaceutical care center and to evaluate the effects of pharmaceutical care on patients who decide to try to stop smoking. The methodology was an open, analytical, pre-post intervention, quasi-experimental clinical study performed with one patient cohort. The results of the study were that the promotional campaign for the smoking cessation program increased the number of patients from one to 22, and after 12 months into the study, 43.48% of the total number of patients achieved total smoking cessation. We can conclude that advertising of a smoking cessation program in a pharmacy increases the number of patients who use the pharmacy's smoking cessation services, and pharmaceutical care is an effective means of achieving smoking cessation. PMID:25678779

  9. Pharmaceutical care in smoking cessation

    PubMed Central

    Marín Armero, Alicia; Calleja Hernandez, Miguel A; Perez-Vicente, Sabina; Martinez-Martinez, Fernando

    2015-01-01

    As a determining factor in various diseases and the leading known cause of preventable mortality and morbidity, tobacco use is the number one public health problem in developed countries. Facing this health problem requires authorities and health professionals to promote, via specific programs, health campaigns that improve patients’ access to smoking cessation services. Pharmaceutical care has a number of specific characteristics that enable the pharmacist, as a health professional, to play an active role in dealing with smoking and deliver positive smoking cessation interventions. The objectives of the study were to assess the efficacy of a smoking cessation campaign carried out at a pharmaceutical care center and to evaluate the effects of pharmaceutical care on patients who decide to try to stop smoking. The methodology was an open, analytical, pre–post intervention, quasi-experimental clinical study performed with one patient cohort. The results of the study were that the promotional campaign for the smoking cessation program increased the number of patients from one to 22, and after 12 months into the study, 43.48% of the total number of patients achieved total smoking cessation. We can conclude that advertising of a smoking cessation program in a pharmacy increases the number of patients who use the pharmacy’s smoking cessation services, and pharmaceutical care is an effective means of achieving smoking cessation. PMID:25678779

  10. Biological and Pharmaceutical Nanomaterials

    NASA Astrophysics Data System (ADS)

    Kumar, Challa S. S. R.

    2006-01-01

    This first comprehensive yet concise overview of all important classes of biological and pharmaceutical nanomaterials presents in one volume the different kinds of natural biological compounds that form nanomaterials or that may be used to purposefully create them. This unique single source of information brings together the many articles published in specialized journals, which often remain unseen by members of other, related disciplines. Covering pharmaceutical, nucleic acid, peptide and DNA-Chitosan nanoparticles, the book focuses on those innovative materials and technologies needed for the continued growth of medicine, healthcare, pharmaceuticals and human wellness. For chemists, biochemists, cell biologists, materials scientists, biologists, and those working in the pharmaceutical and chemical industries.

  11. [Healthy pharmaceutical policy].

    PubMed

    González Pier, Eduardo

    2008-01-01

    Today, the pharmaceutical industry is experiencing a profound transition. Globalization and technological advancement represent the principal pressures for change in the market, where it is increasingly more difficult for this type of industry to efficiently recoup the growing cost of innovation. Mexico needs to analyze the policy implications of these change factors and promote, in the pharmaceutical market, policies that maximize health gains on invested resources. Pharmaceutical policy offers a rare example for a complementary approach between a sound health policy and an efficient economic policy; that is, a "healthy pharmaceutical policy."

  12. [Pharmaceuticals as pollution].

    PubMed

    Grung, Merete; Langford, Katherine; Thomas, Kevin V

    2012-05-29

    The pharmaceuticals we humans use to treat illness and disease typically enter the aquatic environment via the sewer network and wastewater treatment works. Understanding the risks posed to the aquatic environment by these chemicals requires an understanding of the concentrations that exist in the environment and whether they are sufficiently high to have adverse effects on aquatic organisms. The main source of pharmaceuticals to wastewater treatment works is pharmaceuticals used by the general population. Only a small contribution is believed to come from hospitals. The predicted environmental concentrations of pharmaceuticals suggest that certain pharmaceuticals may pose a risk to the environment, but measurement of the actual concentrations present in effluents and recipient waters suggest that sophisticated wastewater treatment is effective for significantly reducing effluent concentrations, and that environmental concentrations of pharmaceuticals, in the Oslo Fjord, for example, are generally low. Humans also excrete the metabolites of the pharmaceuticals that they have used and these too may be released into the environment, sometimes in greater concentrations than the parent drug. The occurrence of most pharmaceuticals and their metabolites in the environment poses little acute environmental risk. However, the effects of long-term chronic exposure to these compounds are still poorly understood and the long-terms risks to the environment are still not clear. What is clear is that certain pharmaceuticals pose a greater environmental risk than others, and that where possible this knowledge should be used to inform users of more environmentally friendly alternatives.

  13. Metrology in Pharmaceutical Industry - A Case Study

    NASA Astrophysics Data System (ADS)

    Yuvamoto, Priscila D.; Fermam, Ricardo K. S.; Nascimento, Elizabeth S.

    2016-07-01

    Metrology is recognized by improving production process, increasing the productivity, giving more reliability to the measurements and consequently, it impacts in the economy of a country. Pharmaceutical area developed GMP (Good Manufacture Practice) requeriments, with no introduction of metrological concepts. However, due to Nanomedicines, it is expected this approach and the consequent positive results. The aim of this work is to verify the level of metrology implementation in a Brazilian pharmaceutical industry, using a case study. The purpose is a better mutual comprehension by both areas, acting together and governmental support to robustness of Brazilian pharmaceutical area.

  14. Drug information residency rotation with pharmaceutical industry.

    PubMed

    Cramer, R L

    1986-01-01

    A drug information rotation in pharmaceutical industry may be elected as a component of a hospital pharmacy residency program. Program objectives include improving communication between the pharmaceutical industry and hospital pharmacy/academia, exposing the resident to the challenges the pharmaceutical industry encounters, improving proficiency in drug information practice, and providing insight into the working relationships of various departments within the company. During the rotation, the resident serves as a member of the Drug Information Service. Resident activities include participating in interviews with corporate professionals, updating pharmacokinetic profiles, responding to drug information requests and participating in other information projects. This rotation enables the resident to better understand pharmaceutical industry's concerns and relate these concerns to clinical pharmacy practice. PMID:10277398

  15. Improving Thermomechanical Properties of SiC/SiC Composites

    NASA Technical Reports Server (NTRS)

    DiCarlo, James A.; Bhatt, Ramakrishna T.

    2006-01-01

    Today, a major thrust toward improving the thermomechanical properties of engine components lies in the development of fiber-reinforced silicon carbide matrix composite materials, including SiC-fiber/SiC-matrix composites. These materials are lighter in weight and capable of withstanding higher temperatures, relative to state-of-the-art metallic alloys and oxide-matrix composites for which maximum use temperatures are in the vicinity of 1,100 C. In addition, the toughness or damage tolerance of the SiC-matrix composites is significantly greater than that of unreinforced silicon-based monolithic ceramics. For successful application in advanced engine systems, the SiC-matrix composites should be able to withstand component service stresses and temperatures for the desired component lifetimes. Inasmuch as the high-temperature structural lives of ceramic materials are typically limited by creep-induced growth of flaws, a key property required of such composite materials is high resistance to creep under conditions of use. Also, the thermal conductivity of the materials should be as high as possible so as to minimize component thermal gradients and thermal stresses. A state-of-the-art SiC-matrix composite is typically fabricated in a three-step process: (1) fabrication of a component-shaped architectural preform reinforced by thermally stable high-performance fibers, (2) chemical-vapor infiltration (CVI) of a fiber-coating material such as boron nitride (BN) into the preform, and (3) infiltration of an SiC-based matrix into the remaining porosity in the preform. Generally, the matrices of the highest-performing composites are fabricated by initial use of a CVI SiC matrix component that is typically more thermally stable and denser than matrix components formed by processes other than CVI. As such, the initial SiC matrix component made by CVI provides better environmental protection to the coated fibers embedded within it. Also, the denser CVI SiC imparts to the

  16. Biosafe Nanoscale Pharmaceutical Adjuvant Materials

    PubMed Central

    Jin, Shubin; Li, Shengliang; Wang, Chongxi; Liu, Juan; Yang, Xiaolong; Wang, Paul C.; Zhang, Xin; Liang, Xing-Jie

    2014-01-01

    Thanks to developments in the field of nanotechnology over the past decades, more and more biosafe nanoscale materials have become available for use as pharmaceutical adjuvants in medical research. Nanomaterials possess unique properties which could be employed to develop drug carriers with longer circulation time, higher loading capacity, better stability in physiological conditions, controlled drug release, and targeted drug delivery. In this review article, we will review recent progress in the application of representative organic, inorganic and hybrid biosafe nanoscale materials in pharmaceutical research, especially focusing on nanomaterial-based novel drug delivery systems. In addition, we briefly discuss the advantages and notable functions that make these nanomaterials suitable for the design of new medicines; the biosafety of each material discussed in this article is also highlighted to provide a comprehensive understanding of their adjuvant attributes. PMID:25429253

  17. Radiation treatment of pharmaceuticals

    NASA Astrophysics Data System (ADS)

    Dám, A. M.; Gazsó, L. G.; Kaewpila, S.; Maschek, I.

    1996-03-01

    Product specific doses were calculated for pharmaceuticals to be radiation treated. Radio-pasteurization dose were determined for some heat sensitive pharmaceutical basic materials (pancreaton, neopancreatin, neopancreatin USP, duodenum extract). Using the new recommendation (ISO standards, Method 1) dose calculations were performed and radiation sterilization doses were determined for aprotinine and heparine Na.

  18. Pharmaceutical technology management--profitable business avenue.

    PubMed

    Puthli, Shivanand P

    2010-01-01

    Growing research expenditure, regulatory framework and generic erosion have forced pharmaceutical companies globally to resort to pharmaceutical technology management (PTM). Indeed, the pharmaceutical industry has witnessed the impact of innovative drug delivery and device technologies and their influence on business. PTM has given a new business insight with greater profits and enhancement of product franchise. Promising breakthrough technologies have not been able to reach a commercial platform largely owing to lack of capital at the preliminary stages of the product development program. Intellectual property plays a considerable role in protecting innovative technologies. Joint ventures and strategic alliances also become important for commercializing a new technology. The synergy of PTM with options of in-licensing is expected to infuse newer opportunities to the pharmaceutical business. PMID:20017657

  19. FDA pharmaceutical quality oversight.

    PubMed

    Yu, Lawrence X; Woodcock, Janet

    2015-08-01

    The launch of the Center for Drug Evaluation and Research (CDER) Office of Pharmaceutical Quality (OPQ) is a milestone in FDA's efforts to assure that quality medicines are available to the American public. As a new super-office within CDER, OPQ is strategically organized to streamline regulatory processes, advance regulatory standards, align areas of expertise, and originate surveillance of drug quality. Supporting these objectives will be an innovative and systematic approach to product quality knowledge management and informatics. Concerted strategies will bring parity to the oversight of innovator and generic drugs as well as domestic and international facilities. OPQ will promote and encourage the adoption of emerging pharmaceutical technology to enhance pharmaceutical quality and potentially reinvigorate the pharmaceutical manufacturing sector in the United States. With a motto of "One Quality Voice," OPQ embodies the closer integration of review, inspection, surveillance, policy, and research for the purpose of strengthening pharmaceutical quality on a global scale.

  20. Component morphology, size, and compositional impact on pharmaceutical powder blend flowability

    NASA Astrophysics Data System (ADS)

    Goldfarb, David; Nakagawa, Hirotaka; Conway, Stephen

    2014-11-01

    Through analysis of particle morphology, particle size, and compositional influences, we present experimental case studies revealing unexpected transitions in flowability and cohesion of pharmaceutical powder blends. We explore interactions between the needle-like API (Active Pharmaceutical Ingredient) and the more spherical remaining components (excipients) in the blend to explain these transitions, and optimal concentrations are identified. A range of particle sizes, aspect ratios (for API), and compositions were examined. Surprisingly, under certain conditions, a blend with a low API concentration exhibits less cohesive flowability properties than a placebo blend containing no API. Effective volume and coordination number models are tested by investigation of particle geometry, particle contact, and Van der Waals force factors. These results should translate both to the improved understanding of mixed component morphology systems and to a novel approach towards pharmaceutical product formulation optimization.

  1. Another development in pharmaceuticals: an introduction.

    PubMed

    Streky, G

    1985-01-01

    The provision of appropriate medicines of the right kind, quality and quantity, and at reasonable prices is a central concern for any government. Simultaneously, there is increasing recognition of the serious problems inherent in the existing systems of pharmaceutical development, promotion, marketing, distribution and use in all countries and particularly in the 3rd World. The vast majority of people in most 3rd World countries have little or no access to effective and safe medicines. The Dag Hammarskjold Foundation organized a consultation on Another Development in Pharmaceuticals in June 1985. It was based on some papers commissioned for that occasion with a view to developing new approaches to fundamental problems in this field and involving both national and international actors and institutions. The basic concern of these papers was to place the debate on pharmaceuticals in its proper historical, contemporary and future context. The 5 major areas discussed were: 1) man and medicines: a historical perspective; 2) towards a healthy use of pharmaceuticals; 3) towards a healthy pharmaceutical industry by the year 2000; 4) 1st principles for the prescription, promotion and use of pharmaceuticals: towards a code of conduct; and 5) monitoring Another Development in Pharmaceuticals. 90% of the world's production of pharmaceuticals originates in the industrialized countries, which also accounts for 80% of the consumption. 3rd World countries have been supplied with a very inappropriate assortment of products by the pharmaceutical industry. There is a growing demand for improved practices that are conducive to health development. An international harmonization of regulatory standards is needed. PMID:12341048

  2. Pharmaceutical prospects of phytoestrogens.

    PubMed

    Usui, Takeshi

    2006-02-01

    Interest in the physiologic and pharmacologic role of bioactive compounds present in plants has increased dramatically over the last decade. Of particular interest in relation to human health are the classes of compounds known as the phytoestrogens, which embody several groups of non-steroidal estrogens, including isoflavones and lignans that are widely distributed within nature. The impact of dietary phytoestrogens on normal biologic processes was first recognized in sheep. Observations of sheep grazing on fields rich in clover and cheetahs fed high soy diets in zoos suggested that flavonoids and related phytochemicals can affect mammalian health. Endogenous estrogens have an important role not only in the hypothalamic-pituitary-gonadal axis, but also in various non-gonadal systems, such as cardiovascular systems, bone, and central nervous systems, and lipid metabolism. There have been several clinical studies of hormone replacement therapy (HRT) in post-menopausal women to examine whether HRT has beneficial effects on the cardiovascular system, bone fractures, lipid metabolism, and Alzheimer's disease. In addition, estrogen contributes to the development of some estrogen-dependent cancers, such as breast cancer and prostate cancer and the number of patients with these cancers is increasing in developed countries. Although recent mega-studies showed negative results for classical HRT in the prevention of some of these diseases, the molecules that interact with estrogen receptors are candidate drugs for various diseases, including hormone-dependent cancers. This review focuses on the molecular properties and pharmaceutical potential of phytoestrogens.

  3. Behavior of selected pharmaceuticals in topsoil of Greyic Phaeozem

    NASA Astrophysics Data System (ADS)

    Kodesova, Radka; Klement, Ales; Kocarek, Martin; Fer, Miroslav; Golovko, Oksana; Grabic, Roman; Jaksik, Ondrej

    2014-05-01

    It has been documented in several studies that soil may be contaminated by human or veterinary pharmaceuticals. Some of pharmaceutical ingredient may be retained in soils. The rest can be transported to the surface and groundwater through surface runoff and infiltration. Mobility of contaminants in soils is dependent on many soil and pharmaceutical properties (e.g. pharmaceutical adsorption on soil particles and pharmaceutical degradation). The goals of this study were: (1) to measure adsorption isotherms of selected pharmaceuticals in one soil; (2) to evaluate degradation of selected pharmaceuticals in this soil, and (3) to evaluate impact of applied pharmaceuticals on biological activity in soil, which influences pharmaceutical decomposition. Batch sorption tests were performed for 7 selected pharmaceuticals (beta blockers Atenolol and Metoprolol, anticonvulsant Carbamazepin, and antibiotics Clarithromycin, Clindamycin, Trimetoprim and Sulfamethoxazol) and one soil (topsoil of Greyic Phaeozem from Čáslav). The same concentrations (0.5, 1, 2.5, 5 and 10 mg/l) were used for almost all pharmaceuticals except Clarithromycin (0.033, 0.08, 0.165, 0.25, 0.33 mg/l). The Freundlich equations were used to describe adsorption isotherms. Degradation of all 7 pharmaceuticals was also studied. Solutes of different pharmaceuticals (concentration of 8.3 mg/l) were added into the plastic bottles (one pharmaceutical per bottle) with soil. Concentrations of pharmaceuticals remaining in soil 1, 2, 5, 12, 23, 40 and 61 days after the pharmaceutical application were analyzed. Colony forming unites were evaluated to describe microbial activity in time affected by different pharmaceuticals. Adsorption of studied pharmaceuticals on soil particles decreasing as follows: Clarithromycin, Trimetoprim, Metoprolol, Clindamycin, Atenolol, Carbamazepin, Sulfamethoxazol. Degradation rates in some degree reflected adsorption of studied pharmaceuticals on soil particles and increased with

  4. Improved austenitic stainless steel for high temperature applications. [Improved stress-rupture properties

    DOEpatents

    Not Available

    This invention describes a composition for an austenitic stainless steel which has been found to exhibit improved high temperature stress rupture properties. The composition of this alloy is about (in wt. %): 12.5 to 14.5 Cr; 14.5 to 16.5 Ni; 1.5 to 2.5 Mo; 1.5 to 2.5 Mn; 0.1 to 0.4 Ti; 0.02 to 0.08 C; 0.5 to 1.0 Si; 0.01 maximum, N; 0.02 to 0.08 P; 0.002 to 0.008 B; 0.004-0.010 S; 0.02-0.05 Nb; .01-.05 V; 0.005-0.02 Ta; 0.02-0.05 Al; 0.01-0.04 Cu; 0.02-0.05 Co; .03 maximum, As; 0.01 maximum, 0; 0.01 maximum, Zr; and with the balance of the alloy being essentially iron. The carbon content of the alloy is adjusted such that wt. % Ti/(wt. % C+wt. % N) is between 4 and 6, and most preferably about 5. In addition the sum of the wt. % P + wt. % B + wt. % S is at least 0.03 wt. %. This alloy is believed to be particularly well suited for use as fast breeder reactor fuel element cladding.

  5. Do technical and commercial biases contribute to the pharmaceutical industry's productivity problems? An analysis of how reordering priorities can improve productivity.

    PubMed

    Fryburg, David A

    2010-09-01

    Of the many issues that contribute to the pharmaceutical industry's productivity problems, biases in the drug discovery and development (DDD) process should be included on the list. The dominant bias pervading the early DDD process is the requirement to identify and develop a commercializable molecule, long before the importance of the target in human disease is understood. That requirement filters out many potentially valuable projects. By changing the emphasis from identifying a commercializable molecule to using molecular tools to test the relevance of the mechanism in humans, the projected number of proofs of concept and subsequent launches could increase up to fivefold. Because this tool paradigm requires resources, one consideration is to form a consortium to share the burden, benefiting both the industry and patients in need.

  6. Pharmaceuticals: pharmaceutical cost controls--2005. End of Year Issue Brief.

    PubMed

    Seay, Melicia; Varma, Priya

    2005-12-31

    The enactment of the Omnibus Budget Reconciliation Act of 1990 (OBRA '90) gave states the option of offering pharmaceutical benefits within their Medicaid programs. But the law placed restrictions on states' flexibility to control what prescriptions they would cover and required the states to reimburse outpatient prescription drugs from manufacturers that signed rebate agreements with the U.S. Department of Health and Human Services. Forty-nine states--Arizona is excluded, based on its program structure--and the District of Columbia currently offer prescription drug coverage under the Medicaid Drug Rebate Program. During the past four years, states all over the country have been plagued with revenue shortfalls in their state Medicaid budgets. While the fiscal situation improved for most states in the 2004 legislative session, many states still face budget pressures in 2005. Compounding existing budget pressures are threats from the Bush Administration to shift increased costs of the Medicaid program on to the states. All things considered, the economic pressure of funding Medicaid is at the top of legislative agendas in 2005. As in previous years, states are attempting to reduce costs to their Medicaid programs by seeking savings in their pharmaceutical programs. Prescription drug costs are highly attributed as a contributing factor to the fiscal climate of state Medicaid programs. Currently, prescription drug spending outpaces that of every other category of health care and drug prices are rising faster than inflation. In response, states are instituting a variety of pharmaceutical cost control measures such as creating preferred drug lists (PDLs), negotiating supplemental rebates, forming bulk purchasing pools, promoting generic drug substitution and implementing price controls. As prescription drug cost containment tools have gained acceptance and momentum, they continue to be controversial. This issue brief explores the debate, history, methodology, utilization

  7. Optimization of microtubule affinity regulating kinase (MARK) inhibitors with improved physical properties.

    PubMed

    Sloman, David L; Noucti, Njamkou; Altman, Michael D; Chen, Dapeng; Mislak, Andrea C; Szewczak, Alexander; Hayashi, Mansuo; Warren, Lee; Dellovade, Tammy; Wu, Zhenhua; Marcus, Jacob; Walker, Deborah; Su, Hua-Poo; Edavettal, Suzanne C; Munshi, Sanjeev; Hutton, Michael; Nuthall, Hugh; Stanton, Matthew G

    2016-09-01

    Inhibition of microtubule affinity regulating kinase (MARK) represents a potentially attractive means of arresting neurofibrillary tangle pathology in Alzheimer's disease. This manuscript outlines efforts to optimize a pyrazolopyrimidine series of MARK inhibitors by focusing on improvements in potency, physical properties and attributes amenable to CNS penetration. A unique cylcyclohexyldiamine scaffold was identified that led to remarkable improvements in potency, opening up opportunities to reduce MW, Pgp efflux and improve pharmacokinetic properties while also conferring improved solubility. PMID:27491711

  8. Chitosan fibers with improved biological and mechanical properties for tissue engineering applications.

    PubMed

    Albanna, Mohammad Z; Bou-Akl, Therese H; Blowytsky, Oksana; Walters, Henry L; Matthew, Howard W T

    2013-04-01

    The low mechanical properties of hydrogel materials such as chitosan hinder their broad utility for tissue engineering applications. Previous research efforts improved the mechanical properties of chitosan fiber through chemical and physical modifications; however, unfavorable toxicity effects on cells were reported. In this paper, we report the preparation of chitosan fibers with improved mechanical and biocompatibility properties. The structure-property relationships of extruded chitosan fibers were explored by varying acetic acid (AA) concentration, ammonia concentration, annealing temperature and degree of heparin crosslinking. Results showed that optimizing AA concentration to 2vol% improved fiber strength and stiffness by 2-fold. Extruding chitosan solution into 25wt% of ammonia solution reduced fiber diameters and improved fiber strength by 2-fold and stiffness by 3-fold, due to an increase in crystallinity as confirmed by XRD. Fiber annealing further reduced fiber diameter and improved fiber strength and stiffness as temperature increased. Chitosan fibers crosslinked with heparin had increased diameter but lower strength and stiffness properties and higher breaking strain values. When individual parameters were combined, further improvement in fiber mechanical properties was achieved. All mechanically improved fibers and heparin crosslinked fibers promoted valvular interstitial cells (VIC) attachment and growth over 10 day cultures. Our results demonstrate the ability to substantially improve the mechanical properties of chitosan fibers without adversely affecting their biological properties. The investigated treatments offer numerous advantages over previous physical/chemical modifications and thus are expected to expand the utility of chitosan fibers with tunable mechanical properties in various tissue engineering applications.

  9. Rejection of pharmaceuticals by forward osmosis membranes.

    PubMed

    Jin, Xue; Shan, Junhong; Wang, Can; Wei, Jing; Tang, Chuyang Y

    2012-08-15

    Rejection of four pharmaceutical compounds, carbamazepine, diclofenac, ibuprofen and naproxen, by forward osmosis (FO) membranes was investigated in this study. For the first time, the rejection efficiency of the pharmaceutical compounds was compared between commercial cellulose triacetate (CTA) based membranes and thin film composite (TFC) polyamide based membranes. The rejection behavior was related to membrane interfacial properties, physicochemical characteristics of the pharmaceutical molecules and feed solution pH. TFC polyamide membranes exhibited excellent overall performance, with high water flux, excellent pH stability and great rejection of all pharmaceuticals investigated (>94%). For commercial CTA based FO membranes, hydrophobic interaction between the compounds and membranes exhibited strong influence on their rejection under acidic conditions. The pharmaceuticals rejection was well correlated to their hydrophobicity (log D). Under alkaline conditions, both electrostatic repulsion and size exclusion contributed to the removal of deprotonated molecules. The pharmaceuticals rejection by CTA-HW membrane at pH 8 followed the order: diclofenac (99%)>carbamazepine (95%)>ibuprofen (93%) ≈ naproxen (93%). These results can be important for FO membrane synthesis, modification and their application in water purification. PMID:22640821

  10. Drug Information Residency Rotation with Pharmaceutical Industry.

    ERIC Educational Resources Information Center

    Cramer, Richard L.

    1986-01-01

    Program objectives of a drug information rotation at the Upjohn Company include improving communication between the pharmaceutical industry and hospital pharmacy/academia, exposing the resident to the challenges the industry encounters, improving proficiency in drug information practice, and providing insight into the working relationships of…

  11. Pharmaceutical Industry in Syria

    PubMed Central

    2010-01-01

    The aim of this article is to present the development of the pharmaceutical industry in Syria using national and international public data sources. At the end of the 80ies, the pharmaceutical industry in Syria was very poor, covering 6% of the national needs. In less than 20 years, with the government support in terms of legal frame and strategic political engagement, the Syrian pharmaceutical industry finally covered almost 90% of the national needs, in terms of drugs, and exported drugs in around 52 Arabian countries. Beyond covering the local market, the main added values of this huge development consisted in exporting drugs in amount of 150 million dollars per year and providing jobs for 17000 Syrian people, out of which around 85% are women. Strong and weak points of the pharmaceutical sector are taken into consideration in the article and further interventions to support a sustainable development are proposed by the author. PMID:20945828

  12. Understanding pharmaceutical quality by design.

    PubMed

    Yu, Lawrence X; Amidon, Gregory; Khan, Mansoor A; Hoag, Stephen W; Polli, James; Raju, G K; Woodcock, Janet

    2014-07-01

    This review further clarifies the concept of pharmaceutical quality by design (QbD) and describes its objectives. QbD elements include the following: (1) a quality target product profile (QTPP) that identifies the critical quality attributes (CQAs) of the drug product; (2) product design and understanding including identification of critical material attributes (CMAs); (3) process design and understanding including identification of critical process parameters (CPPs), linking CMAs and CPPs to CQAs; (4) a control strategy that includes specifications for the drug substance(s), excipient(s), and drug product as well as controls for each step of the manufacturing process; and (5) process capability and continual improvement. QbD tools and studies include prior knowledge, risk assessment, mechanistic models, design of experiments (DoE) and data analysis, and process analytical technology (PAT). As the pharmaceutical industry moves toward the implementation of pharmaceutical QbD, a common terminology, understanding of concepts and expectations are necessary. This understanding will facilitate better communication between those involved in risk-based drug development and drug application review.

  13. Halogenases: A Biotechnological Alternative for the Synthesis of Halogenated Pharmaceuticals.

    PubMed

    Ayala, Marcela; Segovia, Lorenzo; Torres, Eduardo

    2016-01-01

    The role of halogen atoms in pharmaceutical compounds has been recently revised, due to the weak interaction through the so called "halogen bond" between small molecules and proteins or other biomacromolecules, which could be fundamental for binding at a particular site within the macromolecule. Moreover, thousands of natural halogenated compounds have been described to date, pointing to a functional role of halogen atoms in these compounds, as well as a diversity of halogenating enzymes involved in the synthesis of these halogenated metabolites. In this mini-review the different halogenases described to date are presented, particularly those catalyzing halogenation reactions with potential applications in the pharmaceutical field. Oxidative halogenases following an electrophilic halogenation mechanism are the oldest and best characterized halogenases; however, novel halogenases following a nucleophilic halogenation mechanism have been recently described. The catalytic properties as well as the selectivity of some of these enzymes can be modulated through protein engineering, both by single point mutations or by directed evolution; on the other hand, metabolic pathway engineering has been used to improve the production of halogenated metabolites, as well as to produce novel halogenated compounds, potentially important in the pharmaceutical field. Recent advances and prospective on the field of enzymatic halogenation are covered.

  14. Methods for improving the gas barrier properties of polymeric containers

    SciTech Connect

    Hahn, G.J.

    1984-10-23

    Methods are disclosed for the treatment of food, beverage, and medicine containers and the like, which are made of organic polymeric resins, to greatly increase the gas barrier properties thereof. The containers are ion-plated with a very thin flexible layer of an inorganic oxide.

  15. Using glucosamine to improve the properties of photocrosslinked gelatin scaffolds.

    PubMed

    Suo, Hairui; Xu, Kedi; Zheng, Xiaoxiang

    2015-02-01

    The use of hydrogel-based cell transport scaffolds holds great promise in regenerative medicine, such as treating osteoarthritis. Gelatin and glucosamine are the ideal materials to be used in the hydrogel scaffolds for cartilage regeneration for they could act as compositions of cartilage. To overcome the weak strength of traditional gelatin hydrogels and down-regulate cell toxicity of glucosamine, gelatin and glucosamine molecules were grafted with acrylate groups and covalently crosslinked under photo-radiation to form hydrogels. Hydrogels with tuning physiochemical properties were produced according to different proportions of methacrylate gelatin (GelMA) and N-acryloyl glucosamine (AGA). The process of photocrosslinking was elaborated, and the hypothesis of increasing AGA concentration leading to higher strength of hydrogels was corroborated by testing rheological property and scanning micro-morphological features. A serial of properties, including smaller swelling ratio, lower gelatin dissolution and slower degradation of GelMA/AGA hydrogels with higher AGA concentration further proved our hypothesis. Moreover, AGA molecules showed less cytotoxicity than unmodified glucosamine molecules and the incorporation of AGA molecules in GelMA/AGA hydrogels upregulated cell adhesion and spreading on the hydrogel surface. All of these results indicated that addition of AGA molecules could significantly alter the physiochemical properties of GelMA/AGA hydrogels, which may have broad application prospects in the future.

  16. IMPROVED PHYSICAL PROPERTIES OF ZEIN USING GLYOXAL AS A CROSSLINKER

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of crosslinkers glyoxal, methylglyoxal and formaldehyde on physical properties of zein films was studied. Zein was solubilized in 90%(v/v) aqueous ethanol and the pH was adjusted with either hydrochloric acid or sodium hydroxide. Crosslinkers were added to 0.3, 1, 3 and 6%(w/w by zein w...

  17. IMPROVED PHYSICAL PROPERTIES OF ZEIN USING GLYOXAL AS A CROSSLINKER

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of crosslinkers glyoxal, methylglyoxal and formaldehyde on physical properties of zein films was studied. Crosslinker concentrations varied from 0.3 to 6% by zein weight. Films crosslinked with glyoxal and formaldehyde showed a significant increase in tensile strength under certain pH c...

  18. Improving the cold flow properties of biodiesel by fractionation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production of biodiesel is increasing world-wide and contributing to the growing development of renewable alternative fuels. Biodiesel has many fuel properties such as density, viscosity, lubricity, and cetane number that make it compatible for combustion in compression-ignition (diesel) engines. ...

  19. Human pharmaceutical products in the environment - the "problem" in perspective.

    PubMed

    Taylor, David; Senac, Thomas

    2014-11-01

    Concerns about the potential for significant environmental impact from residues of human pharmaceuticals emerged at the beginning of the 21st century. Since then there has been an exponential rise in the number of publications and conferences on this "problem". However, this intense focus on human pharmaceuticals is misplaced. Pharmaceuticals do not consist of a coherent group of substances with similar chemical, structural, biological or toxicological properties. Pharmaceuticals are only identifiable from their use: in other words substances can be divided into two classes, those that are used as pharmaceuticals and those for which a possible pharmaceutical use has not yet been discovered. For example, nitro-glycerine, Warfarin and dimethyl fumarate, initially sold respectively as an explosive, a rodenticide and a mould inhibitor have subsequently all been used as pharmaceuticals. As analytical science advances, an increasing range of environmental contaminants, including pharmaceuticals, is being identified at sub μgL(-1) concentrations. Although, human and environmental exposure to these contaminants will be low, all of them need to be subjected to risk assessment on a case by case basis. Many of these substances, including human pharmaceuticals, may have little, if any, impact on human health or the environment, however for some substances there may be a significant risk and in these cases appropriate action should be taken. However considering all human pharmaceuticals as a special case, isolated from the wider range of emerging contaminants, is scientifically unjustifiable and diverts resources away from the consideration of other substances that may be of considerably more significance.

  20. [Social change and Pharmaceutical Affairs Law (PAL)].

    PubMed

    Masuyama, Koichi; Isobe, Soichiro

    2010-01-01

    Former Japanese pharmaceutical laws, originally based on the Pharmaceutical Marketing and Handling Regulations enacted in 1874 were in operation for many years before World War II. However, in order to address several drug issues, such as poor drug quality and insufficiences regarding the role of pharmacists during the War, the laws needed to be unified and revised. In this paper, we analyzed the record of discussions held by the Imperial Diet on the bill for the Pharmaceutical Affairs Law (PAL) in 1943. This is also regarded as the origin of the current PAL (LawNo.145 in 1960). Through this analysis, we tried to clarify the relationship between the social change and the role of PAL in society. During the War, the bill was discussed, aiming at the improvement of both human resources who treated drugs, and the quality of drug materials. Diet members discussed three main points, namely, "the duty of pharmacists", "the mission of the Japan Pharmaceutical Association" and "the quality control of pharmaceutical products". Notably, the bill pharmacists are required not only to dispense drugs, a role they had previously, but also to manage drug and food hygiene through the quality control of pharmaceutical products and the inspection of food and drink, in order to improve the public health in Japan. Originally, the law was passed to deal with the extraordinary circumstances during the War, but through our analysis, we found that they proactively improved the role of the law to comply with various drug issues raised during the War, the rapid change of the pharmaceutical hygiene concept and the social transformation. PMID:21032892

  1. Fate and mobility of pharmaceuticals in solid matrices.

    PubMed

    Drillia, Panagiota; Stamatelatou, Katerina; Lyberatos, Gerasimos

    2005-08-01

    The sorption and mobility of six pharmaceuticals were investigated in two soil types with different organic carbon and clay content, and in bacterial biomass (aerobic and anaerobic). The pharmaceuticals examined were carbamazepine, propranolol, diclofenac sodium, clofibric acid, sulfamethoxazole and ofloxacin. The sorption experiments were performed according to the OECD test Guideline 106. The distribution coefficients determined by this batch equilibrium method varied with the pharmaceutical tested and the solid matrix type. Ofloxacin was particularly strongly adsorbed (except of the case of using anaerobic biomass for the solid matrix) while clofibric acid was found to be weakly adsorbed. The fate of pharmaceuticals in soil was also assessed using lysimeters. Important parameters that were studied were: the pharmaceutical loading rate and the hydraulic loading rate for adsorption and the rate and duration of a "rain" event for desorption. Major differences in the mobility of the six pharmaceuticals were observed and correlated with the adsorption/desorption properties of the compounds.

  2. Terahertz study on porosity and mass fraction of active pharmaceutical ingredient of pharmaceutical tablets.

    PubMed

    Bawuah, Prince; Tan, Nicholas; Tweneboah, Samuel Nana A; Ervasti, Tuomas; Axel Zeitler, J; Ketolainen, Jarkko; Peiponen, Kai-Erik

    2016-08-01

    In this study, terahertz time-domain spectroscopic (THz-TDS) technique has been used to ascertain the change in the optical properties, as a function of changing porosity and mass fraction of active pharmaceutical ingredient (API), of training sets of pharmaceutical tablets. Four training sets of pharmaceutical tablets were compressed with microcrystalline cellulose (MCC) excipient and indomethacin API by varying either the porosity, height, and API mass fraction or all three tablet parameters. It was observed, as far as we know, for the first time, that the THz time-domain and frequency-domain effective refractive index, as well as, the frequency-domain effective absorption coefficient both show linear correlations with the porosity and API mass fraction for training sets of real pharmaceutical tablets. We suggest that, the observed linear correlations can be useful in basic research and quality inspection of pharmaceutical tablets. Additionally, we propose a novel optical strain parameter, based on THz measurement, which yields information on the conventional strain parameter of a tablet as well as on the change of fill fraction of solid material during compression of porous pharmaceutical tablets. We suggest that the THz measurement and proposed method of data analysis, in addition to providing an efficient tool for basic research of porous media, can serve as one of the novel quality by design (QbD) implementation techniques to predict critical quality attributes (CQA) such as porosity, API mass fraction and strain of flat-faced pharmaceutical tablets before production. PMID:27288937

  3. Cultivation and characterization of bacterial isolates capable of degrading pharmaceutical and personal care products for improved removal in activated sludge wastewater treatment.

    PubMed

    Zhou, Nicolette A; Lutovsky, April C; Andaker, Greta L; Gough, Heidi L; Ferguson, John F

    2013-11-01

    Pharmaceutical and personal care products (PPCPs) discharged with wastewater treatment plant (WWTP) effluents are an emerging surface water quality concern. Biological transformation has been identified as an important removal mechanism during wastewater treatment. The aim of this research was the identification of bacteria with characteristics for potential bioaugmentation to enhance PPCP removal. We report here the cultivation and characterization of bacteria capable of degrading PPCPs to ng/L concentrations. An isolation approach was developed using serial enrichment in mineral medium containing 1 mg/L of an individual PPCP as the sole organic carbon source available to heterotrophs until the original activated sludge inocula was diluted to ~10(-8) of its initial concentration, followed by colony growth on solid R2A agar. Eleven bacteria were isolated, eight that could remove triclosan, bisphenol A, ibuprofen, or 17β-estradiol to below 10 ng/L, one that could remove gemfibrozil to below 60 ng/L, and two that could remove triclosan or E2, but not to ng/L concentrations. Most bacterial isolates degraded contaminants during early growth when grown utilizing rich carbon sources and were only able to degrade the PPCPs on which they were isolated. Seven of the bacterial isolates were sphingomonads, including all the triclosan and bisphenol A degraders and the ibuprofen degrader. The study results indicate that the isolated bacteria may have a positive influence on removal in WWTPs if present at sufficient concentrations and may be useful for bioaugmentation.

  4. 24 CFR 201.20 - Property improvement loan eligibility.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... improvements that are started after loan approval, unless: (i) The prior approval of the Secretary is obtained... preservation of historic structures. (2) Where the proceeds are to be used for a fire safety equipment loan... jurisdiction over the fire safety requirements of health care facilities prior to making application for a loan....

  5. In-vivo mechanical tissue property measurement for improved simulations

    NASA Astrophysics Data System (ADS)

    Ottensmeyer, Mark P.; Salisbury, J. Kenneth, Jr.

    2000-08-01

    Surgical training today, beyond what can be learned in didactic form or practice on animal or other models, is subject to the availability of appropriate training cases from which students can learn. This is especially true for battlefield surgery, as civilian hospitals may not expose doctors to frequent examples of relevant injuries. To provide a more uniform training experience, covering a standard suite of typical operations without relying on the misfortune of patients requiring surgery, many groups are developing computer-based surgical simulation systems. One of the current areas of development is the implementation of force and tactile (haptic) feedback in simulations. To create a model with realistic haptic feedback, knowledge of the material properties of the tissues in question is essential. While there is much data from tissue samples in vitro, the properties of living tissue in situ are mostly unknown. From the data that is available, it is clear that living tissue and tissue in vitro can have radically different mechanical properties. For this reason, our group is developing surgical tools that will be able to measure the force-displacement characteristics of a variety of tissues in living organisms. Taking these data over the range of frequencies relevant to haptic simulation provides information to extract stiffness and material damping parameters of different kinds of tissue. The tools are being designed for use during minimally invasive surgery, but will permit data to be acquired either during MIS or open procedures. Animal tests are expected to commence in early 2000, but the tools are being designed with safety considerations in mind for eventual use in humans. Data will be taken both for solid organs and for selected elements of the vasculature. These data will be used in simulation systems under development at the Center for Innovative Minimally Invasive Therapy at Massachusetts General Hospital and the Laboratory for Human and Machine Haptics

  6. Iron aluminide alloys with improved properties for high temperature applications

    DOEpatents

    McKamey, Claudette G.; Liu, Chain T.

    1990-01-01

    An improved iron aluminide alloy of the DO.sub.3 type that has increased room temperature ductility and improved high elevated temperature strength. The alloy system further is resistant to corrosive attack in the environments of advanced energy corrosion systems such as those using fossil fuels. The resultant alloy is relatively inexpensive as contrasted to nickel based and high nickel steels currently utilized for structural components. The alloy system consists essentially of 26-30 at. % aluminum, 0.5-10 at. % chromium, 0.02-0.3 at. % boron plus carbon, up to 2 at. % molybdenum, up to 1 at. % niobium, up to 0.5 at. % zirconium, up to 0.1 at. % yttrium, up to 0.5 at. % vanadium and the balance iron.

  7. Iron aluminide alloys with improved properties for high temperature applications

    DOEpatents

    McKamey, C.G.; Liu, C.T.

    1990-10-09

    An improved iron aluminide alloy of the DO[sub 3] type is described that has increased room temperature ductility and improved high elevated temperature strength. The alloy system further is resistant to corrosive attack in the environments of advanced energy conversion systems such as those using fossil fuels. The resultant alloy is relatively inexpensive as contrasted to nickel based and high nickel steels currently utilized for structural components. The alloy system consists essentially of 26--30 at. % aluminum, 0.5--10 at. % chromium, 0.02--0.3 at. % boron plus carbon, up to 2 at. % molybdenum, up to 1 at. % niobium, up to 0.5 at. % zirconium, up to 0.1 at. % yttrium, up to 0.5 at. % vanadium and the balance iron. 3 figs.

  8. Improved Icephobic Properties on Surfaces with a Hydrophilic Lubricating Liquid.

    PubMed

    Ozbay, Salih; Yuceel, Cigdem; Erbil, H Yildirim

    2015-10-01

    Slippery liquid-infused porous surfaces were developed recently for icephobic surface applications. Perfluorinated liquids, silicone oil, hydrocarbon, and water were used as lubricating liquids to form a continuous layer on a suitable substrate to prevent icing. However, ice accretion performances of these surfaces have not been reported previously depending on the type of the lubricant. In this work, fluorinated aliphatics, polyalphaolefin, silicone oil, and decamethylcyclopenta siloxane were used as hydrophobic lubricants; water, ethylene glycol, formamide, and water-glycerine mixture were used as hydrophilic lubricants to be impregnated by hydrophobic polypropylene and hydrophilic cellulose-based filter paper surfaces; ice accretion, drop freezing delay time, and ice adhesion strength properties of these surfaces were examined; and the results were compared to those of the reference surfaces such as aluminum, copper, polypropylene, and polytetrafluoroethylene. An ice accretion test method was also developed to investigate the increase of the mass of formed ice gravimetrically by spraying supercooled water onto these surfaces at different subzero temperatures ranging between -1 and -5 °C. It was determined that hydrophilic solvents (especially a water-glycerine mixture) that impregnated hydrophilic porous surfaces would be a promising candidate for anti-icing applications at -2 °C and 56-83% relative humidity because ice accretion and ice adhesion strength properties of these surface decreased simultaneously in these conditions. PMID:26375386

  9. Improved Carrier-Transport Properties of Passivated Cdmnte Crystals

    SciTech Connect

    Kim, K.; Camarda, G; Bolotnikov, A; James, R; Hong, J; Kim, S

    2009-01-01

    By analyzing photoconductive decay curves, we compared the surface recombination velocities of semi-insulating CdMnTe:In crystals grown by the vertical Bridgman method with or without surface passivation. Sulfur passivation effectively prevents the formation of a conductive Te oxide layer on the CdMnTe surface and reduces the surface recombination velocities by about one third. We demonstrated, from IR observations of the distribution maps of Te precipitates, that their configuration affects the anomalous photoconductive decay curves and the gamma-ray spectrum in some areas of the CdMnTe crystal. Notably, not only the size but also the spatial configuration of the Te precipitates modulates the carrier-transport properties.

  10. Magnetic nanoparticles supported ionic liquids improve firefly luciferase properties.

    PubMed

    Noori, Ali Reza; Hosseinkhani, Saman; Ghiasi, Parisa; Akbari, Jafar; Heydari, Akbar

    2014-03-01

    Ionic liquids as neoteric solvents, microwave irradiation, and alternative energy source are becoming as a solvent for many enzymatic reactions. We recently showed that the incubation of firefly luciferase from Photinus pyralis with various ionic liquids increased the activity and stability of luciferase. Magnetic nanoparticles supported ionic liquids have been obtained by covalent bonding of ionic liquids-silane on magnetic silica nanoparticles. In the present study, the effects of [γ-Fe2O3@SiO2][BMImCl] and [γ-Fe2O3@SiO2][BMImI] were investigated on the structural properties and function of luciferase using circular dichroism, fluorescence spectroscopy, and bioluminescence assay. Enzyme activity and structural stability increased in the presence of magnetic nanoparticles supported ionic liquids. Furthermore, the effect of ingredients which were used was not considerable on K(m) value of luciferase for adenosine-5'-triphosphate and also K(m) value for luciferin.

  11. Hydroxyapatite reinforced collagen scaffolds with improved architecture and mechanical properties.

    PubMed

    Kane, Robert J; Weiss-Bilka, Holly E; Meagher, Matthew J; Liu, Yongxing; Gargac, Joshua A; Niebur, Glen L; Wagner, Diane R; Roeder, Ryan K

    2015-04-01

    Hydroxyapatite (HA) reinforced collagen scaffolds have shown promise for synthetic bone graft substitutes and tissue engineering scaffolds. Freeze-dried HA-collagen scaffolds are readily fabricated and have exhibited osteogenicity in vivo, but are limited by an inherent scaffold architecture that results in a relatively small pore size and weak mechanical properties. In order to overcome these limitations, HA-collagen scaffolds were prepared by compression molding HA reinforcements and paraffin microspheres within a suspension of concentrated collagen fibrils (∼ 180 mg/mL), cross-linking the collagen matrix, and leaching the paraffin porogen. HA-collagen scaffolds exhibited an architecture with high porosity (85-90%), interconnected pores ∼ 300-400 μm in size, and struts ∼ 3-100 μm in thickness containing 0-80 vol% HA whisker or powder reinforcements. HA reinforcement enabled a compressive modulus of up to ∼ 1 MPa, which was an order of magnitude greater than unreinforced collagen scaffolds. The compressive modulus was also at least one order of magnitude greater than comparable freeze-dried HA-collagen scaffolds and two orders of magnitude greater than absorbable collagen sponges used clinically. Moreover, scaffolds reinforced with up to 60 vol% HA exhibited fully recoverable elastic deformation upon loading to 50% compressive strain for at least 100,000 cycles. Thus, the scaffold mechanical properties were well-suited for surgical handling, fixation, and bearing osteogenic loads during bone regeneration. The scaffold architecture, permeability, and composition were shown to be conducive to the infiltration and differentiation of adipose-derive stromal cells in vitro. Acellular scaffolds were demonstrated to induce angiogenesis and osteogenesis after subcutaneous ectopic implantation by recruiting endogenous cell populations, suggesting that the scaffolds were osteoinductive.

  12. Improved field emission property of graphene paper by plasma treatment

    SciTech Connect

    Liu Jianlong; Zeng Baoqing; Wu Zhe; Zhu Jinfeng; Liu Xingchong

    2010-07-19

    Lateral orientation and aggregation of the graphene sheets limited field enhancement of graphene paper (GP). To improve the field enhancement of GP, argon plasma treatment was induced to destroy the aggregation and cause formation of surface protrusions. After Ar plasma treatment, turn-on field and threshold field of GP were reduced from 2.3 V/mum to 1.6 V/mum and 4.4 V/mum to 3.0 V/mum, respectively. The enhancement was attributed to the protrusions. Scanning electron microscopy and hydrophobicity had been used to prove the morphology change after plasma treatment.

  13. [Fourcroy and pharmaceutical journals].

    PubMed

    Bonnemain, Bruno

    2011-04-01

    Cadet de Gassicourt wrote a brief Eloge of Fourcroy in January 1810 as he died in December of 1809. Fourcroy had a major role concerning the new ideas on the place of pharmacy at the beginning of the 19th century. Fourcroy has had a key influence for the start of several pharmaceutical journals that wanted to emphasize the link between the new chemistry and pharmacy. None of these journals created with him will survive and one has to wait for 1909 to see the creation, without Fourcroy, of a new pharmaceutical journal, the "Journal de Pharmacie" that will become "Journal de Pharmacie et des Sciences accessoires", then "Journal de Pharmacie et de Chimie", before taking the name of"Annales Pharmaceutiques Françaises", the present official journal of the French Academy of Pharmacy. In spite of the essential role of Fourcroy at the start of pharmaceutical journals, Cadet did not even mention it in his Eloge of 1810.

  14. Polymer/Silicate Nanocomposites Developed for Improved Thermal Stability and Barrier Properties

    NASA Technical Reports Server (NTRS)

    Campbell, Sandi G.

    2001-01-01

    The nanoscale reinforcement of polymers is becoming an attractive means of improving the properties and stability of polymers. Polymer-silicate nanocomposites are a relatively new class of materials with phase dimensions typically on the order of a few nanometers. Because of their nanometer-size features, nanocomposites possess unique properties typically not shared by more conventional composites. Polymer-layered silicate nanocomposites can attain a certain degree of stiffness, strength, and barrier properties with far less ceramic content than comparable glass- or mineral-reinforced polymers. Reinforcement of existing and new polyimides by this method offers an opportunity to greatly improve existing polymer properties without altering current synthetic or processing procedures.

  15. Improvement of the energetic properties of the GPR

    NASA Astrophysics Data System (ADS)

    Pochanin, Gennadiy P.; Ruban, Vadim P.; Kholod, Pavlo V.; Shuba, Alexander A.; Pochanin, Alexander G.; Orlenko, Alexander A.

    2014-05-01

    The necessary condition for the expansion of the impulse Ground Penetrating Radar (GPR) applications is to improve the GPR energy performance for the detection of signals on the background of noise. Digital signal processing techniques allow suppressing the noise largely, but they work only when the GPR is able to register the reflected signals. The majority of the modern GPRs use sampling receivers. They allow recording signals of a very short du- ration. However, very large energy losses are inherent to this method. To improve the signal to noise ratio it is possible to increase the power of the probing signal and to de- crease the noise level of the receiver. In GPR, the transmitting and receiving antennas are usually electrodynamically coupled because they are situated quite close to each other. The sensitive input circuit of the receiver does not allow the excess of the signal amplitude typically more than 1 V. Thus, the increase of the intensity of the probing signal is possible only up to a certain level. To overcome this limitation, it was proposed to design an antenna in such a way that the coupling between the transmitting and receiving sections was absent or minimal. A special method that provided the decoupling below -64 dB was invented (theoretically the isolation is absolute and frequency independent). In order to register as short as possible signals, researchers strive to make sample duration of the sampling converter as short as possible. However, the shorter the sample duration, the smaller the energy of the signal that can be received and the larger the noise. Due to the dispersive absorption of electromagnetic waves in the ground, the high-frequency part of the signal spectrum is attenuated faster than the low-frequency part. It makes no sense to expect the arrival of very short pulses from deep reflectors. Thus, it is possible to increase the duration of the samples at reception of the signals from the deep objects. The authors proposed to

  16. New cement additive improves slurry properties and saves cost

    SciTech Connect

    Pollard, R.; Hibbeler, J.; DiLullo, G.; Shotton, E.A.

    1994-12-31

    A new cement additive has been developed which improves slurry performance and reduces cost. The additive is a vitrified aggregate of calcium-magnesium aluminosilicates with potential cementitious reactivity, hereafter abbreviated CMAS. CMAS has been used successfully on oil and gas wells throughout Indonesia. The purpose of this paper is to illustrate the technical enhancements and cost effectiveness of slurries incorporating CMAS. Laboratory data is presented and working mechanisms are defined to highlight CMAS`s positive effect on; compressive strength, fluid loss control, free water control, gas migration control, resistance to strength retrogression and aggressive fluids. Finally, case studies and an economic analysis are presented to show the cost savings for actual well applications.

  17. Hydrolysis by Alcalase Improves Hypoallergenic Properties of Goat Milk Protein

    PubMed Central

    Yun, Sung-Seob; Lee, Won-Jae; Kim, Jin-Wook; Ha, Ho-Kyung; Yoo, Michelle

    2016-01-01

    Goat milk is highly nutritious and is consumed in many countries, but the development of functional foods from goat milk has been slow compared to that for other types of milk. The aim of this study was to develop a goat milk protein hydrolysate (GMPH) with enhanced digestibility and better hypoallergenic properties in comparison with other protein sources such as ovalbumin and soy protein. Goat milk protein was digested with four commercial food-grade proteases (separately) under various conditions to achieve the best hydrolysis of αs -casein and β-lactoglobulin. It was shown that treatment with alcalase (0.4%, 60℃ for 30 min) effectively degraded these two proteins, as determined by SDS-PAGE, measurement of nonprotein nitrogen content, and reverse-phase high-performance liquid chromatography. Hydrolysis with alcalase resulted in a significant decrease in β-lactoglobulin concentration (almost to nil) and a ~40% reduction in the level of αs-casein. Quantification of histamine and TNF-α released from HMC-1 cells (human mast cell line) showed that the GMPH did not induce an allergic response when compared to the control. Hence, the GMPH may be useful for development of novel foods for infants, the elderly, and convalescent patients, to replace cow milk. PMID:27621693

  18. Hydrolysis by Alcalase Improves Hypoallergenic Properties of Goat Milk Protein.

    PubMed

    Jung, Tae-Hwan; Yun, Sung-Seob; Lee, Won-Jae; Kim, Jin-Wook; Ha, Ho-Kyung; Yoo, Michelle; Hwang, Hyo-Jeong; Jeon, Woo-Min; Han, Kyoung-Sik

    2016-01-01

    Goat milk is highly nutritious and is consumed in many countries, but the development of functional foods from goat milk has been slow compared to that for other types of milk. The aim of this study was to develop a goat milk protein hydrolysate (GMPH) with enhanced digestibility and better hypoallergenic properties in comparison with other protein sources such as ovalbumin and soy protein. Goat milk protein was digested with four commercial food-grade proteases (separately) under various conditions to achieve the best hydrolysis of αs -casein and β-lactoglobulin. It was shown that treatment with alcalase (0.4%, 60℃ for 30 min) effectively degraded these two proteins, as determined by SDS-PAGE, measurement of nonprotein nitrogen content, and reverse-phase high-performance liquid chromatography. Hydrolysis with alcalase resulted in a significant decrease in β-lactoglobulin concentration (almost to nil) and a ~40% reduction in the level of αs-casein. Quantification of histamine and TNF-α released from HMC-1 cells (human mast cell line) showed that the GMPH did not induce an allergic response when compared to the control. Hence, the GMPH may be useful for development of novel foods for infants, the elderly, and convalescent patients, to replace cow milk.

  19. Hydrolysis by Alcalase Improves Hypoallergenic Properties of Goat Milk Protein

    PubMed Central

    Yun, Sung-Seob; Lee, Won-Jae; Kim, Jin-Wook; Ha, Ho-Kyung; Yoo, Michelle

    2016-01-01

    Goat milk is highly nutritious and is consumed in many countries, but the development of functional foods from goat milk has been slow compared to that for other types of milk. The aim of this study was to develop a goat milk protein hydrolysate (GMPH) with enhanced digestibility and better hypoallergenic properties in comparison with other protein sources such as ovalbumin and soy protein. Goat milk protein was digested with four commercial food-grade proteases (separately) under various conditions to achieve the best hydrolysis of αs -casein and β-lactoglobulin. It was shown that treatment with alcalase (0.4%, 60℃ for 30 min) effectively degraded these two proteins, as determined by SDS-PAGE, measurement of nonprotein nitrogen content, and reverse-phase high-performance liquid chromatography. Hydrolysis with alcalase resulted in a significant decrease in β-lactoglobulin concentration (almost to nil) and a ~40% reduction in the level of αs-casein. Quantification of histamine and TNF-α released from HMC-1 cells (human mast cell line) showed that the GMPH did not induce an allergic response when compared to the control. Hence, the GMPH may be useful for development of novel foods for infants, the elderly, and convalescent patients, to replace cow milk.

  20. Hydrolysis by Alcalase Improves Hypoallergenic Properties of Goat Milk Protein.

    PubMed

    Jung, Tae-Hwan; Yun, Sung-Seob; Lee, Won-Jae; Kim, Jin-Wook; Ha, Ho-Kyung; Yoo, Michelle; Hwang, Hyo-Jeong; Jeon, Woo-Min; Han, Kyoung-Sik

    2016-01-01

    Goat milk is highly nutritious and is consumed in many countries, but the development of functional foods from goat milk has been slow compared to that for other types of milk. The aim of this study was to develop a goat milk protein hydrolysate (GMPH) with enhanced digestibility and better hypoallergenic properties in comparison with other protein sources such as ovalbumin and soy protein. Goat milk protein was digested with four commercial food-grade proteases (separately) under various conditions to achieve the best hydrolysis of αs -casein and β-lactoglobulin. It was shown that treatment with alcalase (0.4%, 60℃ for 30 min) effectively degraded these two proteins, as determined by SDS-PAGE, measurement of nonprotein nitrogen content, and reverse-phase high-performance liquid chromatography. Hydrolysis with alcalase resulted in a significant decrease in β-lactoglobulin concentration (almost to nil) and a ~40% reduction in the level of αs-casein. Quantification of histamine and TNF-α released from HMC-1 cells (human mast cell line) showed that the GMPH did not induce an allergic response when compared to the control. Hence, the GMPH may be useful for development of novel foods for infants, the elderly, and convalescent patients, to replace cow milk. PMID:27621693

  1. Improving powder flow properties of a direct compression formulation using a two-step glidant mixing process.

    PubMed

    Abe, Hidaka; Yasui, Shinichiro; Kuwata, Aya; Takeuchi, Hirofumi

    2009-07-01

    To improve powder flow of a high-dose direct compression formulation (drug content 30%), we compared a two-step operation for mixing glidants with a conventional one-step glidant mixing process. This two-step mixing operation was studied with two kinds of mixtures; an active pharmaceutical ingredient (API)-glidant combination and a direct compression excipient-glidant combination. The two-step operation permitted the selection of the optimum glidant type and concentration in each glidant-mixing procedure even though the formulation had different powder properties such as micronized API and enlarged direct compression vehicles, whereas the conventional approaches forced the selection of a certain glidant type and concentration at one-step mixing. The addition of 0.5% nonporous silica markedly improved API flow. In contrast, 1.0% porous silica was the appropriate glidant to enhance excipient flow at direct compression excipient-glidant mixing. The two-step operation dominantly enhanced powder flow when the appropriate API-glidant mixture and the suitable direct compression excipients-glidant mixture were blended compared to the one-step operation with its optimum glidant concentration. The results showed that the angle of repose was 43 degrees and the critical orifice diameter was 10 mm in the two-step operation, whereas it was 47 degrees and 16 mm in the one-step operation. The two-step operation of glidant mixing enhanced powder flow of the high-dose direct compression formulation compared with the one-step operation. The two-step operation eliminates the bottleneck of powder flow and allows direct compression to be more worth applying for formulation and process development trials.

  2. Improving powder flow properties of a cohesive lactose monohydrate powder by intensive mechanical dry coating.

    PubMed

    Zhou, Qi; Armstrong, Brian; Larson, Ian; Stewart, Peter J; Morton, David A V

    2010-02-01

    The objective of this study was to improve the cohesive lactose powder flowability. A cohesive lactose monohydrate powder was processed in either a tumbling blender or an intensive mechanical processor with either magnesium stearate or fumed silica. No substantial changes in particle size were detected by laser diffraction following either treatment. The untreated lactose sample exhibited very poor powder flow. Only limited improvements in powder flowability were indicated after the tumbling blending, intensive mechanical processing with the fumed silica or without additives. However, the intensive mechanical processing of the lactose sample with magnesium stearate demonstrated exceptionally large increases in both poured and tapped density as well as notable improvements in all powder flowability indicators examined. Our findings support the use of intensive mechanical processing technique as an effective method to coat cohesive pharmaceutical powders with selected additives, modify the surface nature of the particles, reduce the interparticle cohesive forces and hence improve powder flowability. The subtle differences in powder flow behaviour of lactose samples between the untreated and tumbling blended powders with magnesium stearate were only detected by the powder rheometer using its dynamic mode, indicating its potential advantages over traditional powder flow characterisation approaches.

  3. An Innovative Pharmaceutical Care Practical Course

    ERIC Educational Resources Information Center

    Bulatova, N. R.; Aburuz, S.; Yousef, A. M.

    2007-01-01

    The innovative practical course was developed to improve the students' ability to acquire pharmaceutical care skills. The primary components of the course were in-school training using small group discussions and hospital experience including identification, analysis, prevention and resolution of drug-therapy problems, patient counseling on their…

  4. Opportunities for pharmaceutical care with critical pathways.

    PubMed

    Koch, K E

    1995-01-01

    Critical pathways are multidisciplinary tools designed to improve patient care and efficiency. Almost every path requires some type of pharmacotherapeutic intervention, from selection of surgical prophylaxis to management of anticoagulation. Pharmacists should become involved with the critical pathway process because it offers an excellent opportunity to incorporate pharmaceutical care and to meet Joint Commission on Accreditation of Healthcare Organization compliance criteria.

  5. GW-1000. GW Pharmaceuticals.

    PubMed

    Smith, Paul F

    2004-07-01

    GW Pharmaceuticals is developing GW-1000 (Sativex), a narrow ratio delta9-tetrahydrocannabinol:cannabidiol product for the potential treatment of multiple sclerosis, spinal cord injury, neurogenic pain and peripheral neuropathy. In March 2003, the company filed for approval for the treatment of MS with the UK Medicines Control Agency, and in May 2004, filed for new drug submission with Health Canada. PMID:15298072

  6. 26 CFR 1.1019-1 - Property on which lessee has made improvements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Basis Rules of General Application § 1.1019-1 Property on... value of such property attributable to such buildings or improvements, the basis of each portion of such... building would have a depreciated value of $50,000, which value the lessor elected to report (beginning...

  7. Method for improving the extraction properties of a tributyl phosphate solution

    DOEpatents

    Martin, Earl C.; Bruns, Lester E.

    1976-01-01

    A method for improving the extraction properties of a tributyl phosphate extractant used for reprocessing irradiated nuclear reactor fuel (Purex Process) containing degradation products of tributyl phosphate by contacting the extractant with diazomethane in a suitable solvent whereby the degradation products are esterified to triester phosphates which have extraction properties similar to those of tributyl phosphate.

  8. 77 FR 23272 - Proposed Information Collection; Comment Request: FHA Insured Title I Property Improvement and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-18

    ... URBAN DEVELOPMENT Proposed Information Collection; Comment Request: FHA Insured Title I Property... information: Title of Proposal: Title I Property Improvement and Manufactured Home Loan Programs. OMB Control Number, if applicable: 2502-0328. Description of the need for the information and proposed use: Title...

  9. Pharmaceutical care education in Kuwait: pharmacy students’ perspectives

    PubMed Central

    Katoue, Maram G.; Awad, Abdelmoneim I.; Schwinghammer, Terry L.; Kombian, Samuel B.

    2014-01-01

    Background Pharmaceutical care is defined as the responsible provision of medication therapy to achieve definite outcomes that improve patients’ quality of life. Pharmacy education should equip students with the knowledge, skills, and attitudes they need to practise pharmaceutical care competently. Objective To investigate pharmacy students’ attitudes towards pharmaceutical care, perceptions of their preparedness to perform pharmaceutical care competencies, opinions about the importance of the various pharmaceutical care activities, and the barriers to its implementation in Kuwait. Methods A descriptive, cross-sectional survey of pharmacy students (n=126) was conducted at Faculty of Pharmacy, Kuwait University. Data were collected via a pre-tested self-administered questionnaire. Descriptive statistics including percentages, medians and means Likert scale rating (SD) were calculated and compared using SPSS, version 19. Statistical significance was accepted at a p value of 0.05 or lower. Results The response rate was 99.2%. Pharmacy students expressed overall positive attitudes towards pharmaceutical care. They felt prepared to implement the various aspects of pharmaceutical care, with the least preparedness in the administrative/management aspects. Perceived pharmaceutical care competencies grew as students progressed through the curriculum. The students also appreciated the importance of the various pharmaceutical care competencies. They agreed/strongly agreed that the major barriers to the integration of pharmaceutical care into practice were lack of private counseling areas or inappropriate pharmacy layout (95.2%), lack of pharmacist time (83.3%), organizational obstacles (82.6%), and pharmacists’ physical separation from patient care areas (82.6%). Conclusion Pharmacy students’ attitudes and perceived preparedness can serve as needs assessment tools to guide curricular change and improvement. Student pharmacists at Kuwait University understand and

  10. Electrostatics of Pharmaceutical Aerosols for Pulmonary Delivery.

    PubMed

    Lip Kwok, Philip Chi

    2015-01-01

    This paper provides a review on key research findings in the rapidly developing area of pharmaceutical aerosol electrostatics. Solids and liquids can become charged without electric fields, the former by contact or friction and the latter by flowing or spraying. Therefore, charged particles and droplets carrying net charges are produced from pharmaceutical inhalers (e.g. dry powder inhalers, metered dose inhalers, and nebulisers) due to the mechanical processes involved in aerosolisation. The charging depends on many physicochemical factors, such as formulation composition, solid state properties, inhaler material and design, and relative humidity. In silico, in vitro, and limited in vivo studies have shown that electrostatic charges may potentially influence particle deposition in the airways. However, the evidence is not yet conclusive. Furthermore, there are currently no regulatory requirements on the characterisation and control of the electrostatic properties of inhaled formulations. Besides the need for further investigations on the relationship between physicochemical factors and charging characteristics of the aerosols, controlled and detailed in vivo studies are also required to confirm whether charges can affect particle deposition in the airways. Since pharmaceutical aerosol electrostatics is a relatively new research area, much remains to be explored. Thus there is certainly potential for development. New findings in the future may contribute to the advancement of pharmaceutical aerosol formulations and respiratory drug delivery.

  11. Electrostatics of Pharmaceutical Aerosols for Pulmonary Delivery.

    PubMed

    Lip Kwok, Philip Chi

    2015-01-01

    This paper provides a review on key research findings in the rapidly developing area of pharmaceutical aerosol electrostatics. Solids and liquids can become charged without electric fields, the former by contact or friction and the latter by flowing or spraying. Therefore, charged particles and droplets carrying net charges are produced from pharmaceutical inhalers (e.g. dry powder inhalers, metered dose inhalers, and nebulisers) due to the mechanical processes involved in aerosolisation. The charging depends on many physicochemical factors, such as formulation composition, solid state properties, inhaler material and design, and relative humidity. In silico, in vitro, and limited in vivo studies have shown that electrostatic charges may potentially influence particle deposition in the airways. However, the evidence is not yet conclusive. Furthermore, there are currently no regulatory requirements on the characterisation and control of the electrostatic properties of inhaled formulations. Besides the need for further investigations on the relationship between physicochemical factors and charging characteristics of the aerosols, controlled and detailed in vivo studies are also required to confirm whether charges can affect particle deposition in the airways. Since pharmaceutical aerosol electrostatics is a relatively new research area, much remains to be explored. Thus there is certainly potential for development. New findings in the future may contribute to the advancement of pharmaceutical aerosol formulations and respiratory drug delivery. PMID:26290198

  12. Improving the antifouling property of polysulfone ultrafiltration membrane by incorporation of isocyanate-treated graphene oxide.

    PubMed

    Zhao, Haiyang; Wu, Liguang; Zhou, Zhijun; Zhang, Lin; Chen, Huanlin

    2013-06-21

    In this paper, isocyanate-treated graphene oxide (iGO), which can be well dispersed in organic solvent, was prepared in a simple manner and showed excellent compatibility with polysulfone (PSF). iGO-PSF ultrafiltration membranes were prepared by the classical phase inversion method. The separation performance and the antifouling property of the prepared membranes were investigated in detail. The antifouling property of the prepared membranes was found to be greatly enhanced by the addition of iGO, and we attributed the enhanced antifouling property to the improved hydrophilicity, the more negative zeta potential and the improved smoothness of the membrane surface.

  13. Artificial neural networks: theoretical background and pharmaceutical applications: a review.

    PubMed

    Wesolowski, Marek; Suchacz, Bogdan

    2012-01-01

    In recent times, there has been a growing interest in artificial neural networks, which are a rough simulation of the information processing ability of the human brain, as modern and vastly sophisticated computational techniques. This interest has also been reflected in the pharmaceutical sciences. This paper presents a review of articles on the subject of the application of neural networks as effective tools assisting the solution of various problems in science and the pharmaceutical industry, especially those characterized by multivariate and nonlinear dependencies. After a short description of theoretical background and practical basics concerning the computations performed by means of neural networks, the most important pharmaceutical applications of neural networks, with suitable references, are demonstrated. The huge role played by neural networks in pharmaceutical analysis, pharmaceutical technology, and searching for the relationships between the chemical structure and the properties of newly synthesized compounds as candidates for drugs is discussed.

  14. EU pharmaceutical expenditure forecast

    PubMed Central

    Urbinati, Duccio; Rémuzat, Cécile; Kornfeld, Åsa; Vataire, Anne-Lise; Cetinsoy, Laurent; Aballéa, Samuel; Mzoughi, Olfa; Toumi, Mondher

    2014-01-01

    Background and Objectives With constant incentives for healthcare payers to contain their pharmaceutical budgets, forecasting has become critically important. Some countries have, for instance, developed pharmaceutical horizon scanning units. The objective of this project was to build a model to assess the net effect of the entrance of new patented medicinal products versus medicinal products going off-patent, with a defined forecast horizon, on selected European Union (EU) Member States’ pharmaceutical budgets. This model took into account population ageing, as well as current and future country-specific pricing, reimbursement, and market access policies (the project was performed for the European Commission; see http://ec.europa.eu/health/healthcare/key_documents/index_en.htm). Method In order to have a representative heterogeneity of EU Member States, the following countries were selected for the analysis: France, Germany, Greece, Hungary, Poland, Portugal, and the United Kingdom. A forecasting period of 5 years (2012–2016) was chosen to assess the net pharmaceutical budget impact. A model for generics and biosimilars was developed for each country. The model estimated a separate and combined effect of the direct and indirect impacts of the patent cliff. A second model, estimating the sales development and the risk of development failure, was developed for new drugs. New drugs were reviewed individually to assess their clinical potential and translate it into commercial potential. The forecast was carried out according to three perspectives (healthcare public payer, society, and manufacturer), and several types of distribution chains (retail, hospital, and combined retail and hospital). Probabilistic and deterministic sensitivity analyses were carried out. Results According to the model, all countries experienced drug budget reductions except Poland (+€41 million). Savings were expected to be the highest in the United Kingdom (−€9,367 million), France

  15. Two-phase chromium-niobium alloys exhibiting improved mechanical properties at high temperatures

    DOEpatents

    Liu, C.T.; Takeyama, Masao.

    1994-02-01

    The specification discloses chromium-niobium alloys which exhibit improved mechanical properties at high temperatures in the range of 1250 C and improved room temperature ductility. The alloys contain a Cr[sub 2]Nb-rich intermetallic phase and a Cr-rich phase with an overall niobium concentration in the range of from about 5 to about 18 at. %. The high temperature strength is substantially greater than that of state of the art nickel-based superalloys for enhanced high temperature service. Further improvements in the properties of the compositions are obtained by alloying with rhenium and aluminum; and additional rare-earth and other elements. 14 figures.

  16. Two-phase chromium-niobium alloys exhibiting improved mechanical properties at high temperatures

    DOEpatents

    Liu, Chain T.; Takeyama, Masao

    1994-01-01

    The specification discloses chromium-niobium alloys which exhibit improved mechanical properties at high temperatures in the range of 1250.degree. C. and improved room temperature ductility. The alloys contain a Cr.sub.2 Nb-rich intermetallic phase and a Cr-rich phase with an overall niobium concentration in the range of from about 5 to about 18 at. %. The high temperature strength is substantially greater than that of state of the art nickel-based superalloys for enhanced high temperature service. Further improvements in the properties of the compositions are obtained by alloying with rhenium and aluminum; and additional rare-earth and other elements.

  17. Pharmaceutical cocrystals: a novel approach for oral bioavailability enhancement of drugs.

    PubMed

    Chadha, Renu; Saini, Anupam; Arora, Poonam; Bhandari, Swati

    2012-01-01

    Solid dosage forms are by far the preferred drug delivery systems. However, these often face the problem of poor and erratic bioavailability during the drug development process. Numerous formulation strategies for drug delivery are currently under development, among which the solid forms such as polymorphs, solvates, salts, and cocrystals have been considered to be the most important for improving dissolution rate and bioavailability. Cocrystallization is a fairly new approach in pharmaceutical industry that can improve the solubility and, consequently, the bioactivity of the active pharmaceutical ingredient (API) without compromising its structural integrity. Pharmaceutical cocrystals have found their place in drug delivery, primarily due to their ability to produce alternative, viable solid forms when a more standard approach of salt and polymorph formation fails to deliver the desired objectives. Over the past few years, a number of papers have been published focusing on a broad range of subjects, from traditional crystal engineering to structure-property relationships of cocrystals. The present review, however, illustrates how the cocrystalline forms of APIs have improved their in vitro dissolution rate and in vivo bioavailability, often correlating well with their improved solubility as well.

  18. Pharmaceutical spray freeze drying.

    PubMed

    Wanning, Stefan; Süverkrüp, Richard; Lamprecht, Alf

    2015-07-01

    Pharmaceutical spray-freeze drying (SFD) includes a heterogeneous set of technologies with primary applications in apparent solubility enhancement, pulmonary drug delivery, intradermal ballistic administration and delivery of vaccines to the nasal mucosa. The methods comprise of three steps: droplet generation, freezing and sublimation drying, which can be matched to the requirements given by the dosage form and route of administration. The objectives, various methods and physicochemical and pharmacological outcomes have been reviewed with a scope including related fields of science and technology.

  19. Hot-Melt Extrusion: from Theory to Application in Pharmaceutical Formulation.

    PubMed

    Patil, Hemlata; Tiwari, Roshan V; Repka, Michael A

    2016-02-01

    Hot-melt extrusion (HME) is a promising technology for the production of new chemical entities in the developmental pipeline and for improving products already on the market. In drug discovery and development, industry estimates that more than 50% of active pharmaceutical ingredients currently used belong to the biopharmaceutical classification system II (BCS class II), which are characterized as poorly water-soluble compounds and result in formulations with low bioavailability. Therefore, there is a critical need for the pharmaceutical industry to develop formulations that will enhance the solubility and ultimately the bioavailability of these compounds. HME technology also offers an opportunity to earn intellectual property, which is evident from an increasing number of patents and publications that have included it as a novel pharmaceutical formulation technology over the past decades. This review had a threefold objective. First, it sought to provide an overview of HME principles and present detailed engineered extrusion equipment designs. Second, it included a number of published reports on the application of HME techniques that covered the fields of solid dispersions, microencapsulation, taste masking, targeted drug delivery systems, sustained release, films, nanotechnology, floating drug delivery systems, implants, and continuous manufacturing using the wet granulation process. Lastly, this review discussed the importance of using the quality by design approach in drug development, evaluated the process analytical technology used in pharmaceutical HME monitoring and control, discussed techniques used in HME, and emphasized the potential for monitoring and controlling hot-melt technology. PMID:26159653

  20. Improvements of physical, mechanical and biodegradation properties of polybutadiene rubber insulators by chitosan and silica nanoparticles.

    PubMed

    Saboktakin, Amin; Saboktakin, Mohammadreza

    2016-10-01

    1,4-cis-Polybutadiene rubber(1,4-cis pBR) as an insulation material is developing that will provide superior thermal insulation properties, flexibility, toughness by natural polymers such as chitosan(CS) and silica nanoparticles. This material is widely used in the insulation industries specially architecture. This research concerns physical, mechanical properties and also biodegradation of 1,4-cis pBR, which to be composed with the natural polymers such as CS. Silica nanoparticles were used as filler to improve the physical and mechanical properties of 1,4-cis pBR. To evaluating its physical and mechanical properties, stretching and bending and impact tests were used and the results show some improvement in these properties. Our observations show that temperature plays an important role as main factor in order to improve the mechanical properties of nanocomposites. Similar improvements in tensile modulus and strength have been observed for 1,4-cis pBR/CS-silica nanoparticles.

  1. Thermoplastic impact property improvement in hybrid natural fibre epoxy composite bumper beam

    NASA Astrophysics Data System (ADS)

    Davoodi, M. M.; Sapuan, S. M.; Ali, Aidy; Ahmad, D.; Khalina, A.

    2010-05-01

    Utilization of thermoset resin as a bumper beam composite matrix is currently more dominated in car manufacturer suppliers, because of availability, easy processing, low material cost and production equipment investment. Moreover, low viscosity, shrinkage and excellent flow facilitate better fibre impregnation and proper surface resin wetting. Three-dimensional cross linking curing increase impact, creep and environmental stress cracking resistance properties. Low impact properties of natural fibre epoxy composite, are main issues in its employment for automotive structural components. Impact properties in epoxy composite bumper beam could be increased by modifying the resin, reinforcement and manufacturing process as well as geometry parameters such as cross section, thickness, added ribs and fixing method optimizations could strengthen impact resistance. There are two main methods, flexibilisation and toughening, as modifying the resin in order to improve the impact properties of epoxy composite, which form single phase or two-phase morphology to make modifier as epoxy or from separate phase to keep the thermo-mechanical properties. Liquid rubber, thermoplastic, core shell particle and rigid particle are different methods of toughening improvements. In this research, thermoplastic toughening has used to improve impact properties in hybrid natural fibre epoxy composite for automotive bumper beam and has achieved reasonable impact improvements.

  2. Improvements of physical, mechanical and biodegradation properties of polybutadiene rubber insulators by chitosan and silica nanoparticles.

    PubMed

    Saboktakin, Amin; Saboktakin, Mohammadreza

    2016-10-01

    1,4-cis-Polybutadiene rubber(1,4-cis pBR) as an insulation material is developing that will provide superior thermal insulation properties, flexibility, toughness by natural polymers such as chitosan(CS) and silica nanoparticles. This material is widely used in the insulation industries specially architecture. This research concerns physical, mechanical properties and also biodegradation of 1,4-cis pBR, which to be composed with the natural polymers such as CS. Silica nanoparticles were used as filler to improve the physical and mechanical properties of 1,4-cis pBR. To evaluating its physical and mechanical properties, stretching and bending and impact tests were used and the results show some improvement in these properties. Our observations show that temperature plays an important role as main factor in order to improve the mechanical properties of nanocomposites. Similar improvements in tensile modulus and strength have been observed for 1,4-cis pBR/CS-silica nanoparticles. PMID:27353394

  3. [Study thought of pharmaceutical preparations quality standards by dynamic quality control technology].

    PubMed

    Yu, Dan-Hong; Mao, Chen-Mei; Lv, Cheng-Zhe; Jin, Hui-Zhen; Yao, Xin; Jia, Xiao-Bin

    2014-07-01

    Pharmaceutical preparations, particularly as a "secret recipe" of traditional Chinese medicine in medical institutions, are the product of China's medical and health industry, and they are also an important means of competing of different medical institutions. Although pharmaceutical preparations have advantages and characteristics than institutes for drug and pharmaceutical companies, the quality standards of pharmaceutical preparations in medical institutions has not reached the desired level over the years. As we all know, the quality of pharmaceutical preparations is important to ensure the efficacy, especially under the environment of people pay more sttention on drug safety and effectiveness and contry increase emphasis on the stste of pharmaceutical preparations. In view of this, we will improve the grade, stability, and clinical efficacy of pharmaceutical preparations by the advanced equipment, testing instruments and the process dynamic quality control technology. Finally, we hope we can provide new ideas for the quality control of pharmaceutical preparations.

  4. [Study thought of pharmaceutical preparations quality standards by dynamic quality control technology].

    PubMed

    Yu, Dan-Hong; Mao, Chen-Mei; Lv, Cheng-Zhe; Jin, Hui-Zhen; Yao, Xin; Jia, Xiao-Bin

    2014-07-01

    Pharmaceutical preparations, particularly as a "secret recipe" of traditional Chinese medicine in medical institutions, are the product of China's medical and health industry, and they are also an important means of competing of different medical institutions. Although pharmaceutical preparations have advantages and characteristics than institutes for drug and pharmaceutical companies, the quality standards of pharmaceutical preparations in medical institutions has not reached the desired level over the years. As we all know, the quality of pharmaceutical preparations is important to ensure the efficacy, especially under the environment of people pay more sttention on drug safety and effectiveness and contry increase emphasis on the stste of pharmaceutical preparations. In view of this, we will improve the grade, stability, and clinical efficacy of pharmaceutical preparations by the advanced equipment, testing instruments and the process dynamic quality control technology. Finally, we hope we can provide new ideas for the quality control of pharmaceutical preparations. PMID:25272516

  5. Improving the Dielectric Properties of Ethylene-Glycol Alkanethiol Self-Assembled Monolayers

    PubMed Central

    2014-01-01

    Self-assembled monolayers (SAMs) can be formed at the interface between solids and fluids, and are often used to modify the surface properties of the solid. One of the most widely employed SAM systems is exploiting thiol-gold chemistry, which, together with alkane-chain-based molecules, provides a reliable way of SAM formation to modify the surface properties of electrodes. Oligo ethylene-glycol (OEG) terminated alkanethiol monolayers have shown excellent antifouling properties and have been used extensively for the coating of biosensor electrodes to minimize nonspecific binding. Here, we report the investigation of the dielectric properties of COOH-capped OEG monolayers and demonstrate a strategy to improve the dielectric properties significantly by mixing the OEG SAM with small concentrations of 11-mercaptoundecanol (MUD). The monolayer properties and composition were characterized by means of impedance spectroscopy, water contact angle, ellipsometry and X-ray photoelectron spectroscopy. An equivalent circuit model is proposed to interpret the EIS data and to determine the conductivity of the monolayer. We find that for increasing MUD concentrations up to about 5% the resistivity of the SAM steadily increases, which together with a considerable decrease of the phase of the impedance, demonstrates significantly improved dielectric properties of the monolayer. Such monolayers will find widespread use in applications which depend critically on good dielectric properties such as capacitive biosensor. PMID:24447311

  6. Improvement of mechanical properties of acrylic bone cement by fiber reinforcement.

    PubMed

    Saha, S; Pal, S

    1984-01-01

    Acrylic bone cement is significantly weaker and less stiff than compact bone. Bone cement is also weaker in tension than in compression. This limits its use in orthopaedics to areas where tensile stresses are minimum. We have attempted to improve the mechanical properties of PMMA by reinforcing it with metal wires, and graphite and aramid fibers. Normal, carbon fiber reinforced and aramid fiber reinforced bone cement specimens were tested in compression. Addition of a small percentage (1-2% by weight for carbon and up to 6% for aramid) of these fibers improved the mechanical properties significantly. Due to the improved mechanical properties of fiber reinforced bone cement, its clinical use may reduce the incidence of cement fracture and thus loosening of the prosthesis. PMID:6480622

  7. Wheat Gluten Blends with Maleic Anhydride-Functionalized Polyacrylate Cross-Linkers for Improved Properties.

    PubMed

    Diao, Cheng; Xia, Hongwei; Parnas, Richard S

    2015-10-14

    A family of polyacrylate-based cross-linkers was synthesized to maximize the toughness of high Tg, high modulus wheat gluten blends in the glassy state. Mechanical testing and damping measurements were conducted to provide an example where the work of fracture and strength of the blend substantially exceeds polystyrene while maintaining flexure stiffness in excess of 3 GPa. The new rubbery cross-linkers, polymethyl acrylate-co-maleic anhydride and polyethyl acrylate-co-maleic anhydride, improve WG mechanical properties and reduce water absorption simultaneously. MDSC, FTIR, HPLC, and NMR data confirmed the cross-linking reaction with wheat gluten. Flexural, DMA, and water absorption testing were carried out to characterize the property improvements. DMA was conducted to investigate the relationship between energy damping and mechanical property improvement. If the cross-linker damping temperature is close to the testing temperature, the entire sample exhibits high damping, toughness, and strength.

  8. Improved Conservation Properties for Particle-in-cell Simulations with Kinetic Electrons

    SciTech Connect

    J.L.V. Lewandowski

    2003-06-19

    It is shown that a simple algorithm which exactly segregates between adiabatic and non-adiabatic electrons in particle-in-cell simulations of drift modes yields excellent conservation properties (e.g. particle number, energy) compared to the conventional df scheme. The removal of the free streaming term in the evolution of the marker weight is shown to be responsible for the improved linear and nonlinear properties of the simulated plasma.

  9. Improved gas sensing and dielectric properties of Fe doped hydroxyapatite thick films: Effect of molar concentrations

    SciTech Connect

    Mene, Ravindra U.; Mahabole, Megha P.; Mohite, K.C.; Khairnar, Rajendra S.

    2014-02-01

    Highlights: • We report improved gas sensing and dielectric characteristics of Fe ion exchanged HAp films. • Fe doped HAp film shows maximum gas response at relatively lower temperature. • Response and gas uptake capacity of sensors is improved for appropriate amount of Fe ions in HAp matrix. • Fe-HAp films exhibit remarkable improvement in dielectric properties compared to pure HAp. • Fe doped HAp films show significant improvement in gas sensing as well as in dielectric properties. - Abstract: In the present work Fe doped hydroxyapatite (Fe-HAp) thick films has been successfully utilized to improve the gas sensing as well as its dielectric properties. Initially, HAp nano powder is synthesized by chemical precipitation process and later on Fe ions are doped in HAp by ion exchange process. Structural and morphological modifications are observed by means of X-ray diffraction and scanning electron microscopy analysis. The sensing parameters such as operating temperature, response/recovery time and gas uptake capacity are experimentally determined. The Fe-HAp (0.05 M) film shows improved CO and CO{sub 2} gas sensing capacity at lower operating temperature compared to pure HAp. Moreover, variation of dielectric constant and dielectric loss for pure and Fe-HAp thick films are studied as a function of frequency in the range of 10 Hz–1 MHz. The study reveals that Fe doped HAp thick films improve the sensing and dielectric characteristics as compared to pure HAp.

  10. Pharmaceutical applications of graphene-based nanosheets.

    PubMed

    Kim, Mi-Gyeong; Park, Joo Y; Shon, Yuna; Shim, Gayong; Oh, Yu-Kyoung

    2014-01-01

    Graphene-based nanosheets (GNS) are atomic-thickness monolayers of hexagonally arranged, graphite-derived carbon atoms that may be composed of graphene, graphene oxide, or reduced graphene oxide. They have attracted tremendous interest for their potential in pharmaceutical applications, due to their unique physical, chemical, and mechanical properties GNS exhibit highly uniform surface areas and may have hydroxyl (-OH), epoxide (-O-), and carboxyl functional groups at their basal surfaces and plane edges, depending on their oxidized and reduced surface properties. GNS show high-level optical absorption of near infrared (NIR) light and elevate the temperature of nearby environments. Furthermore, they can be loaded with anticancer drugs via hydrophobic interactions, π-π stacking, or electrostatic binding. Given these properties, GNS can be used in chemotherapy, photodynamic therapy, photothermal therapy, and theranostics. However, although GNS appear to have far-reaching potential in the field of biomedical research, their widespread pharmaceutical application has been limited by issues such as poor stability in physiological buffers, undefined mechanisms of cellular uptake, toxicity problems, and a lack of standard preparation methods. Here, we review the current pharmaceutical applications of GNS, focusing on chemotherapy, phototherapy, combo therapy and theranostic applications with challenging issues.

  11. Chitin and Chitosan as Direct Compression Excipients in Pharmaceutical Applications

    PubMed Central

    Badwan, Adnan A.; Rashid, Iyad; Al Omari, Mahmoud M.H.; Darras, Fouad H.

    2015-01-01

    Despite the numerous uses of chitin and chitosan as new functional materials of high potential in various fields, they are still behind several directly compressible excipients already dominating pharmaceutical applications. There are, however, new attempts to exploit chitin and chitosan in co-processing techniques that provide a product with potential to act as a direct compression (DC) excipient. This review outlines the compression properties of chitin and chitosan in the context of DC pharmaceutical applications. PMID:25810109

  12. Process for improving mechanical properties of epoxy resins by addition of cobalt ions

    NASA Technical Reports Server (NTRS)

    Stoakley, D. M.; St.clair, A. K. (Inventor)

    1984-01-01

    A resin product useful as an adhesive, composite or casting resin is described as well as the process used in its preparation to improve its flexural strength mechanical property characteristics. Improved flexural strength is attained with little or no change in density, thermal stability or moisture resistance by chemically incorporating 1.2% to 10.6% by weight Co(3) ions in an epoxidized resin system.

  13. Relevance of variation in use of terminology to define generic pharmaceutical products.

    PubMed

    Fonseca, Elize Massard da

    2015-02-01

    The World Health Organization (WHO) promotes the use of generic drug policies to foster competition in the pharmaceutical sector, reduce drug prices, and increase access to therapeutic drugs. However, little is known about how countries implement these policies. This article describes different terminology adopted by national regulatory authorities to define generic versus proprietary drug products in developing countries, including those in Latin America, and challenges that arise in their application of WHO guidelines, such as labeling issues. The author concludes that variation in generics terminology in these countries is a result of institutional context (i.e., the public sector setting as well as the body of laws and regulations that exists in the country) and policy legacies, such as intellectual property regimes, and highlights the need for further analysis of pharmaceutical regulations to improve understanding of the barriers and political implications of generic drug policies.

  14. [Adhesive cutaneous pharmaceutical forms].

    PubMed

    Gafiţanu, E; Matei, I; Mungiu, O C; Pavelescu, M; Mîndreci, I; Apostol, I; Ionescu, G

    1989-01-01

    The adhesive cutaneous pharmaceutical forms aimed to local action release the drug substance in view of a dermatological, traumatological, antirheumatic, cosmetic action. Two such preparations were obtained and their stability, consistency and pH were determined. The "in vitro" tests of their bioavailability revealed the dynamics of calcium ions release according to the associations of each preparation. The bioavailability determined by evaluating the pharmacological response demonstrated the antiinflammatory action obtained by the association of calcium ions with the components extracted from poplar muds. The therapeutical efficiency of the studied preparations has proved in the treatment of some sport injuries.

  15. Bolaamphiphiles: A Pharmaceutical Review

    PubMed Central

    Fariya, Mayur; Jain, Ankitkumar; Dhawan, Vivek; Shah, Sanket; Nagarsenker, Mangal S.

    2014-01-01

    The field of drug discovery is ever growing and excipients play a major role in it. A novel class of amphiphiles has been discussed in the review. The review focuses on natural as well as synthetic bolaamphiphiles, their chemical structures and importantly, their ability to self assemble rendering them of great use to pharmaceutical industry. Recent reports on their ability to be used in fabrication of suitable nanosized carriers for drug as well as genes to target site, has been discussed substantially to understand the potential of bolaamphiphiles in field of drug delivery. PMID:25671179

  16. Novel Radiofrequency-Assisted Thermal Processing Improves the Gelling Properties of Standard Egg White Powder.

    PubMed

    Boreddy, Sreenivasula Reddy; Thippareddi, Harshavardhan; Froning, Glenn; Subbiah, Jeyamkondan

    2016-03-01

    Effect of radiofrequency (RF)-assisted thermal processing on quality and functional properties of high-foaming standard egg white powder (std. EWP, pH approximately 7.0) was investigated and compared with traditional processing (heat treatment in a hot room at 58 °C for at least 14 d). The RF-assisted thermal treatments were selected to meet the pasteurization requirements and to improve the functional properties of the std. EWP. The treatment conditions were: RF heating to 60, 70, 80, and 90 °C followed by holding in a hot air oven at those temperatures for different periods ranging from 4 h at 90 °C to 72 h at 60 °C. The quality (color and solubility) and functional properties (foaming properties: foaming capacity and foam stability; and gelling properties: water holding capacity and gel-firmness) of the std. EWP were investigated. RF-assisted thermal processing did not affect the color and solubility of std. EWP at any of the treatment conditions. In general, the foaming and gelling properties of RF-assisted thermally processed std. EWP increased with an increase in temperature and treatment duration. The optimal RF-assisted treatment conditions to produce std. EWP with similar functional properties as the traditionally processed (hot room processed) std. EWP were 90 °C for ≥8 h. These optimal conditions were similar to those for high gel egg white powder (HG-EWP, pH approximately 9.5). The RF-assisted thermal pasteurization improved the gelling properties of std. EWP to the levels of HG-EWP, leading to newer applications of this functionally improved safe product. The RF-assisted thermal processing allows the processor to produce a HG-EWP from std. EWP subsequent to processing while simultaneously pasteurizing the product, thus assuring the product safety. PMID:26869145

  17. Novel Radiofrequency-Assisted Thermal Processing Improves the Gelling Properties of Standard Egg White Powder.

    PubMed

    Boreddy, Sreenivasula Reddy; Thippareddi, Harshavardhan; Froning, Glenn; Subbiah, Jeyamkondan

    2016-03-01

    Effect of radiofrequency (RF)-assisted thermal processing on quality and functional properties of high-foaming standard egg white powder (std. EWP, pH approximately 7.0) was investigated and compared with traditional processing (heat treatment in a hot room at 58 °C for at least 14 d). The RF-assisted thermal treatments were selected to meet the pasteurization requirements and to improve the functional properties of the std. EWP. The treatment conditions were: RF heating to 60, 70, 80, and 90 °C followed by holding in a hot air oven at those temperatures for different periods ranging from 4 h at 90 °C to 72 h at 60 °C. The quality (color and solubility) and functional properties (foaming properties: foaming capacity and foam stability; and gelling properties: water holding capacity and gel-firmness) of the std. EWP were investigated. RF-assisted thermal processing did not affect the color and solubility of std. EWP at any of the treatment conditions. In general, the foaming and gelling properties of RF-assisted thermally processed std. EWP increased with an increase in temperature and treatment duration. The optimal RF-assisted treatment conditions to produce std. EWP with similar functional properties as the traditionally processed (hot room processed) std. EWP were 90 °C for ≥8 h. These optimal conditions were similar to those for high gel egg white powder (HG-EWP, pH approximately 9.5). The RF-assisted thermal pasteurization improved the gelling properties of std. EWP to the levels of HG-EWP, leading to newer applications of this functionally improved safe product. The RF-assisted thermal processing allows the processor to produce a HG-EWP from std. EWP subsequent to processing while simultaneously pasteurizing the product, thus assuring the product safety.

  18. Life cycle analysis within pharmaceutical process optimization and intensification: case study of active pharmaceutical ingredient production.

    PubMed

    Ott, Denise; Kralisch, Dana; Denčić, Ivana; Hessel, Volker; Laribi, Yosra; Perrichon, Philippe D; Berguerand, Charline; Kiwi-Minsker, Lioubov; Loeb, Patrick

    2014-12-01

    As the demand for new drugs is rising, the pharmaceutical industry faces the quest of shortening development time, and thus, reducing the time to market. Environmental aspects typically still play a minor role within the early phase of process development. Nevertheless, it is highly promising to rethink, redesign, and optimize process strategies as early as possible in active pharmaceutical ingredient (API) process development, rather than later at the stage of already established processes. The study presented herein deals with a holistic life-cycle-based process optimization and intensification of a pharmaceutical production process targeting a low-volume, high-value API. Striving for process intensification by transfer from batch to continuous processing, as well as an alternative catalytic system, different process options are evaluated with regard to their environmental impact to identify bottlenecks and improvement potentials for further process development activities.

  19. Peroxidase mediated conjugation of corn fibeer gum and bovine serum albumin to improve emulsifying properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The emulsifying properties of corn fiber gum (CFG), a naturally-occurring polysaccharide protein complex, were improved by kinetically controlled formation of hetero-covalent linkages with bovine serum albumin (BSA), using horseradish peroxidase. The formation of hetero-crosslinked CFG-BSA conjugate...

  20. The Acoustic Properties of Vowels: A Tool for Improving Articulation and Comprehension of English

    ERIC Educational Resources Information Center

    McCombs, Candalene J.

    2006-01-01

    Correct pronunciation is often a later step in the process of teaching English as a second language. However, a focus on the correct articulation of vowels can significantly improve listening and comprehension skills as well as articulatory skills. Vowels and consonants differ in their acoustic properties. Unlike consonants, vowel sounds are…

  1. Experimental and theoretical investigation of the molecular structure, conformational stability, hyperpolarizability, electrostatic potential, thermodynamic properties and NMR spectra of pharmaceutical important molecule: 4'-methylpropiophenone.

    PubMed

    Karunakaran, V; Balachandran, V

    2014-07-15

    Combined experimental and theoretical studies have been performed on the structure and vibrational spectra (IR and Raman spectra) of 4'-methylpropiophenone (MPP). The FT-IR and FT-Raman spectra of 4'-methylpropiophenone (MPP) have been recorded in the region 4000-400 cm(-1) and 3500-100 cm(-1), respectively. The harmonic vibrational frequencies were calculated and the scaled values have been compared with experimental FT-IR and FT-Raman spectra. A detailed interpretation of the infrared and Raman spectra of MPP are also reported based on total energy distribution (TED). The observed and the calculated frequencies are found to be in good agreement. The (1)H and (13)C NMR chemical shifts have been calculated by Gauge-Independent Atomic Orbital (GIAO) method with B3LYP/6-311++G(d,p). The natural bond orbital (NBO), natural hybrid orbital (NHO) analysis and electronic properties, such as HOMO and LUMO energies, were performed by DFT approach. The calculated HOMO and LUMO energies show that charge transfer occurs within molecule. The first order hyperpolarizability (β0) of the novel molecular system and related properties (βtot, α0 and Δα) of MPP are calculated using DFT/6-311++G(d,p) method on the finite-field approach. The Mulliken charges, the values of electric dipole moment (μ) of the molecule were computed using DFT calculations. The thermodynamic functions of the title compound were also performed at the above method and basis set.

  2. Physical exercise improves properties of bone and its collagen network in growing and maturing mice.

    PubMed

    Isaksson, Hanna; Tolvanen, Viivi; Finnilä, Mikko A J; Iivarinen, Jarkko; Tuukkanen, Juha; Seppänen, Kari; Arokoski, Jari P A; Brama, Pieter A; Jurvelin, Jukka S; Helminen, Heikki J

    2009-09-01

    This study characterized bone structure, composition, and mechanical properties in growing male mice. The development of the collagen network during maturation was monitored, and the effect of voluntary physical exercise was investigated. We hypothesized that increased bone loading from exercise would increase the amount and improve the properties of the collagen network during growth and maturation. Half of the mice (total n = 168) had access to running wheels, while half were kept sedentary. Weight and running activity were recorded, and groups of mice were killed at 1, 2, 4, and 6 months of age. The collagen network was assessed by biochemical evaluation of collagen content and cross-links and by tensile testing of decalcified bone. Mineralized femur was analyzed with pQCT and three-point-bending and femoral neck-strength tests. After 6 months, the exercising mice had 10% lower body weight than the sedentary group. There was no difference in the amount of collagen or collagen cross-links, while tensile testing had higher breaking force and stiffness of the collagen network in runners after 4 months but not after 6 months. The bone mineral density and cross-sectional area were higher in the running group after 6 months. Runners also showed higher breaking force and stiffness of the diaphysis and the femoral neck at 2 and 6 months. The significant modulation of mechanical properties of the collagen network without any change in collagen content indicates that physical exercise improves properties of the collagen network in maturing bone. The improvement after exercise of the properties of mineralized bone appears to be more pronounced and long-lasting compared to the early improved properties of the collagen network.

  3. Effective executive management in the pharmaceutical industry.

    PubMed

    Tran, Hoang; Kleiner, Brian H

    2005-01-01

    Along with the boom in information technology and vast development in genomic and proteomic discoveries, the pharmaceutical and biotech industries have been provided the means and tools to create a new page in medicinal history. They are now able to alter the classic ways to cure complex diseases thanks to the completion of the human genome project. To be able to compete in this industry, pharmaceutical management has to be effective not only internally but also externally in socially acceptable conduct. The first department that requires focus is marketing and sales. As the main driving force to increase revenues and profits, marketing and sales employees should be highly motivated by compensation. Also, customer relationships should be maintained for long-term gain. As important as marketing, research and development requires the financial support as well as the critical decision making to further expand the product pipeline. Similarly, finance and technologies should be adequately monitored and invested to provide support as well as prepare for future expansion. On top of that, manufacturing processes and operations are operated per quality systems and FDA guidelines to ensure high quality. Human Resources, on the other hand, should carry the managing and motivation from upper management through systematic recruitment, adequate training, and fair compensation. Moreover, effective management in a pharmaceutical would also require the social welfare and charity to help patients who cannot afford the treatment as well as improving the organization's image. Last but not least, the management should also prepare for the globalization of the industry. Inevitably, large pharmaceutical companies are merging with each other or acquiring smaller companies to enhance the competitive advantages as well as expand their product mix. For effectiveness in a pharmaceutical industry, management should focus more than just the daily routine tasks and short-term goals. Rather, they

  4. Effective executive management in the pharmaceutical industry.

    PubMed

    Tran, Hoang; Kleiner, Brian H

    2005-01-01

    Along with the boom in information technology and vast development in genomic and proteomic discoveries, the pharmaceutical and biotech industries have been provided the means and tools to create a new page in medicinal history. They are now able to alter the classic ways to cure complex diseases thanks to the completion of the human genome project. To be able to compete in this industry, pharmaceutical management has to be effective not only internally but also externally in socially acceptable conduct. The first department that requires focus is marketing and sales. As the main driving force to increase revenues and profits, marketing and sales employees should be highly motivated by compensation. Also, customer relationships should be maintained for long-term gain. As important as marketing, research and development requires the financial support as well as the critical decision making to further expand the product pipeline. Similarly, finance and technologies should be adequately monitored and invested to provide support as well as prepare for future expansion. On top of that, manufacturing processes and operations are operated per quality systems and FDA guidelines to ensure high quality. Human Resources, on the other hand, should carry the managing and motivation from upper management through systematic recruitment, adequate training, and fair compensation. Moreover, effective management in a pharmaceutical would also require the social welfare and charity to help patients who cannot afford the treatment as well as improving the organization's image. Last but not least, the management should also prepare for the globalization of the industry. Inevitably, large pharmaceutical companies are merging with each other or acquiring smaller companies to enhance the competitive advantages as well as expand their product mix. For effectiveness in a pharmaceutical industry, management should focus more than just the daily routine tasks and short-term goals. Rather, they

  5. Improvement of adhesion properties of low density polyethylene (LDPE) substrate using atmospheric plasma

    SciTech Connect

    Sanchez-Nacher, L.; Garcia-Sanoguera, D.; Fenollar, O.; Balart, J.; Fombuena, V.

    2010-06-02

    In this work we have used atmospheric plasma technology on polyethylene surface with different treatment conditions. These modify surface pre-treatments on polyethylene, thus having a positive effect on overall surface activity of polymer surface and, consequently, adhesion properties can be remarkably improved. We have evaluated the influence of the nozzle/substrate distance and atmospheric plasma speed on wettability changes and adhesion properties. Wettability changes have been studied by contact angle measurements and subsequent surface energy calculation. Mechanical characterization of adhesion joints has been carried out in two different ways: peel and shear tensile test. The overall results show a remarkable increase in mechanical properties of adhesion joints for low nozzle/substrate distances and low speed. So plasma atmospheric technology is highly useful to increase adhesion properties of polypropylene.

  6. Improvements of reinforced silica aerogel nanocomposites thermal properties for architecture applications.

    PubMed

    Saboktakin, Amin; Saboktakin, Mohammad Reza

    2015-01-01

    An 1,4-cis polybutadiene rubber/carboxymethyl starch (CMS)-based silica aerogel nanocomposites as a insulation material was developed that will provide superior thermal insulation properties, flexibility, toughness, durability of the parent polymer, yet with the low density and superior insulation properties associated with the aerogels. In this study, reinforced 1,4-cis polybutadiene-CMS-silica aerogel nanocomposites were prepared from a silica aerogel with a surface area 710 m(2) g(-1), a pore size of 25.3 nm and a pore volume of 4.7 cm(3) g(-1). The tensile properties and dynamic mechanical properties of 1,4-cis polybutadiene/CMS nanocomposites were systematically enhanced at low silica loading. Similar improvements in tensile modulus and strength have been observed for 1,4-cis polybutadiene/CMS mesoporous silica aerogel nanocomposites. PMID:25172161

  7. Improvements of reinforced silica aerogel nanocomposites thermal properties for architecture applications.

    PubMed

    Saboktakin, Amin; Saboktakin, Mohammad Reza

    2015-01-01

    An 1,4-cis polybutadiene rubber/carboxymethyl starch (CMS)-based silica aerogel nanocomposites as a insulation material was developed that will provide superior thermal insulation properties, flexibility, toughness, durability of the parent polymer, yet with the low density and superior insulation properties associated with the aerogels. In this study, reinforced 1,4-cis polybutadiene-CMS-silica aerogel nanocomposites were prepared from a silica aerogel with a surface area 710 m(2) g(-1), a pore size of 25.3 nm and a pore volume of 4.7 cm(3) g(-1). The tensile properties and dynamic mechanical properties of 1,4-cis polybutadiene/CMS nanocomposites were systematically enhanced at low silica loading. Similar improvements in tensile modulus and strength have been observed for 1,4-cis polybutadiene/CMS mesoporous silica aerogel nanocomposites.

  8. Pharmaceutical study of Yashadabhasma

    PubMed Central

    Bhojashettar, Santhosh; Jadar, P. G.; Rao, V. Nageswara

    2012-01-01

    Background: Rasashastra is a branch which deals with the pharmaceutics of Rasaoushadhis. Bhasmas are one among such Rasaoushadhis which are known for their low doses and fast action. A verse from Rasaratnasamuchchaya says that the bhasma prepared by using Mercury as media is of best quality. Materials and Methods: Following this principle, Yashadabhasma (Zinc calx) was prepared by subjecting it to Samanya shodhana (general purification method for all metals), Vishesha shodhana (specific putification method for Zinc), Jarana (roasting) and Marana (incineration) with Parada(Mercury) as a media under Gajaputa (classical heating system with 1000 cowdung cakes). Results and Conclusion: Yellow colored Yashadabhasma which passed all the classical bhasmaparikshas (tests for properly prepared calx) was obtained after two putas. The bhasma did not pass Nishchandratva(free from shining particles) test after 1stputa but was passed after giving it 2ndputa. PMID:23284213

  9. Rubisco catalytic properties of wild and domesticated relatives provide scope for improving wheat photosynthesis.

    PubMed

    Prins, Anneke; Orr, Douglas J; Andralojc, P John; Reynolds, Matthew P; Carmo-Silva, Elizabete; Parry, Martin A J

    2016-03-01

    Rubisco is a major target for improving crop photosynthesis and yield, yet natural diversity in catalytic properties of this enzyme is poorly understood. Rubisco from 25 genotypes of the Triticeae tribe, including wild relatives of bread wheat (Triticum aestivum), were surveyed to identify superior enzymes for improving photosynthesis in this crop. In vitro Rubisco carboxylation velocity (V c), Michaelis-Menten constants for CO2 (K c) and O2 (K o) and specificity factor (S c/o) were measured at 25 and 35 °C. V c and K c correlated positively, while V c and S c/o were inversely related. Rubisco large subunit genes (rbcL) were sequenced, and predicted corresponding amino acid differences analysed in relation to the corresponding catalytic properties. The effect of replacing native wheat Rubisco with counterparts from closely related species was analysed by modelling the response of photosynthesis to varying CO2 concentrations. The model predicted that two Rubisco enzymes would increase photosynthetic performance at 25 °C while only one of these also increased photosynthesis at 35 °C. Thus, under otherwise identical conditions, catalytic variation in the Rubiscos analysed is predicted to improve photosynthetic rates at physiological CO2 concentrations. Naturally occurring Rubiscos with superior properties amongst the Triticeae tribe can be exploited to improve wheat photosynthesis and crop productivity. PMID:26798025

  10. Rubisco catalytic properties of wild and domesticated relatives provide scope for improving wheat photosynthesis.

    PubMed

    Prins, Anneke; Orr, Douglas J; Andralojc, P John; Reynolds, Matthew P; Carmo-Silva, Elizabete; Parry, Martin A J

    2016-03-01

    Rubisco is a major target for improving crop photosynthesis and yield, yet natural diversity in catalytic properties of this enzyme is poorly understood. Rubisco from 25 genotypes of the Triticeae tribe, including wild relatives of bread wheat (Triticum aestivum), were surveyed to identify superior enzymes for improving photosynthesis in this crop. In vitro Rubisco carboxylation velocity (V c), Michaelis-Menten constants for CO2 (K c) and O2 (K o) and specificity factor (S c/o) were measured at 25 and 35 °C. V c and K c correlated positively, while V c and S c/o were inversely related. Rubisco large subunit genes (rbcL) were sequenced, and predicted corresponding amino acid differences analysed in relation to the corresponding catalytic properties. The effect of replacing native wheat Rubisco with counterparts from closely related species was analysed by modelling the response of photosynthesis to varying CO2 concentrations. The model predicted that two Rubisco enzymes would increase photosynthetic performance at 25 °C while only one of these also increased photosynthesis at 35 °C. Thus, under otherwise identical conditions, catalytic variation in the Rubiscos analysed is predicted to improve photosynthetic rates at physiological CO2 concentrations. Naturally occurring Rubiscos with superior properties amongst the Triticeae tribe can be exploited to improve wheat photosynthesis and crop productivity.

  11. Rubisco catalytic properties of wild and domesticated relatives provide scope for improving wheat photosynthesis

    PubMed Central

    Prins, Anneke; Orr, Douglas J.; Andralojc, P. John; Reynolds, Matthew P.; Carmo-Silva, Elizabete; Parry, Martin A. J.

    2016-01-01

    Rubisco is a major target for improving crop photosynthesis and yield, yet natural diversity in catalytic properties of this enzyme is poorly understood. Rubisco from 25 genotypes of the Triticeae tribe, including wild relatives of bread wheat (Triticum aestivum), were surveyed to identify superior enzymes for improving photosynthesis in this crop. In vitro Rubisco carboxylation velocity (V c), Michaelis–Menten constants for CO2 (K c) and O2 (K o) and specificity factor (S c/o) were measured at 25 and 35 °C. V c and K c correlated positively, while V c and S c/o were inversely related. Rubisco large subunit genes (rbcL) were sequenced, and predicted corresponding amino acid differences analysed in relation to the corresponding catalytic properties. The effect of replacing native wheat Rubisco with counterparts from closely related species was analysed by modelling the response of photosynthesis to varying CO2 concentrations. The model predicted that two Rubisco enzymes would increase photosynthetic performance at 25 °C while only one of these also increased photosynthesis at 35 °C. Thus, under otherwise identical conditions, catalytic variation in the Rubiscos analysed is predicted to improve photosynthetic rates at physiological CO2 concentrations. Naturally occurring Rubiscos with superior properties amongst the Triticeae tribe can be exploited to improve wheat photosynthesis and crop productivity. PMID:26798025

  12. Energy requirements for methods improving gas detection by modulating physical properties of resistive gas sensors

    NASA Astrophysics Data System (ADS)

    Trawka, M.; Kotarski, M.

    2016-01-01

    One of the most important disadvantage of resistive gas sensors is their limited gas selectivity. Therefore, various methods modulating their physical properties are used to improve gas detection. These methods are usually limited to temperature modulation or UV light irradiation for the layers exhibiting photocatalytic effect. These methods cause increased energy consumption. In our study we consider how much energy has to be supplied to utilize such methods and what kind of additional information can be gathered. We present experimental results of selected resistive gas sensors, including commercial and prototype constructions, and practical solutions of modulating their physical properties.

  13. Improvement of the biomedical properties of titanium using SMAT and thermal oxidation.

    PubMed

    Wen, Ming; Wen, Cuie; Hodgson, Peter; Li, Yuncang

    2014-04-01

    Titanium and its alloys are excellent candidates for biomedical implant. However, they exhibit relatively poor tribological properties. In this study, a two-step treatment including surface mechanical attrition treatment (SMAT) combined with thermal oxidation process has been developed to improve the tribological properties and biocompatibility of Ti. Ti after two-step treatment shows excellent wear-resistance and biocompatibility among all Ti samples, which can be ascribed to the highest surface energy, well crystallinity of rutile layer on its surface. Overall, the two-step treatment is a prospective method to produce excellent biomedical Ti materials.

  14. Improved Electronic Properties of Laser-Doped Emitters by Reducing Surface Roughness

    NASA Astrophysics Data System (ADS)

    Nishimura, Hideki; Hirata, Kenji; Hasegawa, Mitsuhiro; Katagiri, Takuya; Fuyuki, Takashi

    2012-10-01

    Laser doping (LD) can help form emitters at low cost and in high throughput because it operates in air atmosphere and at room temperature. Moreover, LD makes high-efficiency structures in a very simple way by melting and diffusing impurities on selective areas. In this study, evaluation of the relationship between multicrystalline silicon (mc-Si) surface conditions and electric properties is carried out. The results show that the surface electric properties were improved and conversion efficiencies were increased. This was accomplished by changing the surface conditions from rough to smooth by surface etching and vacuum treatment before LD.

  15. Bioplex technology: novel synthetic gene delivery pharmaceutical based on peptides anchored to nucleic acids.

    PubMed

    Simonson, Oscar E; Svahn, Mathias G; Törnquist, Elisabeth; Lundin, Karin E; Smith, C I E

    2005-01-01

    Non-viral gene delivery is an important approach in order to establish safe in vivo gene therapy in the clinic. Although viral vectors currently exhibit superior gene transfer efficacy, the safety aspect of viral gene delivery is a concern. In order to improve non-viral in vivo gene delivery we have designed a pharmaceutical platform called Bioplex (biological complex). The concept of Bioplex is to link functional entities via hybridising anchors, such as Peptide Nucleic Acids (PNA), directly to naked DNA. In order to promote delivery functional entities consisting of biologically active peptides or carbohydrates, are linked to the PNA anchor. The PNA acts as genetic glue and hybridises with DNA in a sequence specific manner. By using functional entities, which elicit receptor-mediated endocytosis, improved endosomal escape and enhance nuclear entry we wish to improve the transfer of genetic material into the cell. An important aspect is that the functional entities should also have tissue-targeting properties in vivo. Examples of functional entities investigated to date are the Simian virus 40 nuclear localisation signal to improve nuclear uptake and different carbohydrate ligands in order to achieve receptor specific uptake. The delivery system is also endowed with regulatory capability, since the release of functional entities can be controlled. The aim is to create a safe, pharmaceutically defined and stable delivery system for nucleic acids with enhanced transfection properties that can be used in the clinic.

  16. [Chapter 1. A contemporary history of the Japanese pharmaceutical industry (1980-2010). A contemporary history of the Japanese Pharmaceutical Industry (1980-2010) Task Force].

    PubMed

    2014-01-01

    This publication, commemorating the sixty years since the founding of Japan Society for the History of Pharmacy (JSHP), provides an overview of the Japanese pharmaceutical industry over a thirty-year span from 1980 to 2010. In the first section, entitled Medical Evolution: The Growth Period for Pharmaceutical Products, and the second section, "Patient-Based Medicine: The Period of Information Prioritization, the following themes are examined. Changes in Drug Pricing Policies, Promotion of Bungyō (separation of prescription from dispensing), Measures to Improve the Safety of Pharmaceutical Products; Appropriate Use of Pharmaceutical Products, Drug Discovery: Changes in Pharmaceutical Product Development and Actual Conditions in the Domestic Launch of New Medicines; Marketing (Medical Representative) Reforms, Pharmaceutical Industry Mergers and Acquisitions, Internationalization of the Pharmaceutical Industry. The following papers are provided as further references to support the conclusions made in the sections above. Changes in Japanese Drug Discovery Technologies and Drug Development. Japan's Pharmaceutical Market and Shifts in Manufacturing and Sales. Changes in Clinical Trials in Japan and Appropriate Use of Pharmaceuticals. Internationalization of the Japanese Pharmaceutical Industry.

  17. [Chapter 1. A contemporary history of the Japanese pharmaceutical industry (1980-2010). A contemporary history of the Japanese Pharmaceutical Industry (1980-2010) Task Force].

    PubMed

    2014-01-01

    This publication, commemorating the sixty years since the founding of Japan Society for the History of Pharmacy (JSHP), provides an overview of the Japanese pharmaceutical industry over a thirty-year span from 1980 to 2010. In the first section, entitled Medical Evolution: The Growth Period for Pharmaceutical Products, and the second section, "Patient-Based Medicine: The Period of Information Prioritization, the following themes are examined. Changes in Drug Pricing Policies, Promotion of Bungyō (separation of prescription from dispensing), Measures to Improve the Safety of Pharmaceutical Products; Appropriate Use of Pharmaceutical Products, Drug Discovery: Changes in Pharmaceutical Product Development and Actual Conditions in the Domestic Launch of New Medicines; Marketing (Medical Representative) Reforms, Pharmaceutical Industry Mergers and Acquisitions, Internationalization of the Pharmaceutical Industry. The following papers are provided as further references to support the conclusions made in the sections above. Changes in Japanese Drug Discovery Technologies and Drug Development. Japan's Pharmaceutical Market and Shifts in Manufacturing and Sales. Changes in Clinical Trials in Japan and Appropriate Use of Pharmaceuticals. Internationalization of the Japanese Pharmaceutical Industry. PMID:25272635

  18. Improving charge transport property and energy transfer with carbon quantum dots in inverted polymer solar cells

    SciTech Connect

    Liu, Chunyu; Chang, Kaiwen; Guo, Wenbin E-mail: chenwy@jlu.edu.cn Li, Hao; Shen, Liang; Chen, Weiyou E-mail: chenwy@jlu.edu.cn; Yan, Dawei E-mail: chenwy@jlu.edu.cn

    2014-08-18

    Carbon quantum dots (Cdots) are synthesized by a simple method and introduced into active layer of polymer solar cells (PSCs). The performance of doped devices was apparently improved, and the highest power conversion efficiency of 7.05% was obtained, corresponding to a 28.2% enhancement compared with that of the contrast device. The charge transport properties, resistance, impedance, and transient absorption spectrum are systematically investigated to explore how the Cdots affect on PSCs performance. This study reveals the importance of Cdots in enhancing the efficiency of PSCs and gives insight into the mechanism of charge transport improvement.

  19. Boron nitride nanotubes included thermally cross-linked gelatin-glucose scaffolds show improved properties.

    PubMed

    Şen, Özlem; Culha, Mustafa

    2016-02-01

    Boron nitride nanotubes (BNNTs) are increasingly investigated for their medical and biomedical applications due to their unique properties such as resistance to oxidation, thermal and electrical insulation, and biocompatibility. BNNTs can be used to enhance mechanical strength of biomedical structures such as scaffolds in tissue engineering applications. In this study, we report the use of BNNTs and hydroxylated BNNTs (BNNT-OH) to improve the properties of gelatin-glucose scaffolds prepared with electrospinning technique. Human dermal fibroblast (HDF) cells are used for the toxicity assessment and cell seeding studies. It is found that the addition of BNNTs into the scaffold does not influence cell viability, decreases the scaffold degradation rate, and improves cell attachment and proliferation compared to only-gelatin scaffold.

  20. Improvement in mechanical properties of plasma sprayed hydroxyapatite coatings by Al2O3 reinforcement.

    PubMed

    Mittal, Manoj; Nath, S K; Prakash, Satya

    2013-07-01

    Thermal sprayed hydroxyapatite coatings suffer from poor mechanical properties like tensile strength, wear resistance, hardness, toughness and fatigue. The mechanical properties of hydroxyapatite coatings can be enhanced via incorporation of secondary bioinert reinforcement material. In this study an attempt has been made to improve the mechanical properties of plasma sprayed hydroxyapatite by reinforcing it with 10, 20 and 30% Al2O3. The plasma sprayed coatings have been characterized using FE-SEM/EDAX, XRD, AFM and FTIR spectroscopy. Corrosion studies have been done in simulated body fluid and abrasive wear studies have been performed on flat specimens on a disk wear tester. Microhardness, tensile strength and wear resistance are found to be increased with increasing Al2O3 content. All types of coatings show superior resistance against corrosion in simulated body fluid.

  1. Improvement of Light Fastness Properties of Dyed Jute Fabrics Through Pretreatment

    NASA Astrophysics Data System (ADS)

    Shahidullah, Md.; Rabiul Islam, Md.; Alamgir Sayeed, M. M.; Kamal Uddin, Md.; Abdullah, A. B. M.

    The chemical treatments such as desizing, scouring, caustic soda mercerization, ammonia mercerization at -33°C and bleaching were carried out on jute fabrics. Then dyeing was done with various reactive dyes applying by standard procedure to investigate the change in different properties like light fastness, moisture regain and nitrogen content has been done on undyed and dyed jute products. It was observed that the moisture regain percentage of the jute fabrics increased after different treatments and the moisture regain percentage of dyed fabrics decreased in all the cases. The nitrogen content percentage of the ammonia treated and dyed fabrics were higher than other treated and undyed jute fabrics. Therefore light fastness properties of the ammonia treated and dyed fabrics will be adequate. So, it can be concluded that anhydrous liquid ammonia (-33°C) treatment improves light fastness properties of dyed jute fabrics for the diversification of jute for value addition.

  2. Catechin-Modified Polylactide Stereocomplex at Chain End Improved Antibiobacterial Property.

    PubMed

    Ajiro, Hiroharu; Ito, Shogo; Kan, Kai; Akashi, Mitsuru

    2016-05-01

    Using different type of initiators, the antibacterial moieties are introduced at the chain end of poly(L,L-lactide) (PLLA) and poly(D,D-lactide) (PDLA), and the thermal properties are simultaneously improved using the stereocomplex approach. The physical interaction of polymers and antibacterial compounds is investigated. The double bonds at the chain end are utilized for the interaction of silver ion; however, the silver ions are not detected after stereocomplexation of PLLA and PDLA. On the other hand, catechin (CT) is selected as an initiator precursor of lactide polymerization, protecting the phenolic hydroxyl groups. The linear PLLA and PDLA are obtained by the initiator, resulting in CT conjugated PLAs at the chain end groups after deprotection of phenolic hydroxyl groups. The antibacterial properties are determined by proliferation tests of staphylococcus aureus. The results suggest that the antibacterial properties of CT modified PLAs are derived from the original CT parts. PMID:26789009

  3. Improved dynamic properties of natural rubber filled with irradiation-modified carbon black

    NASA Astrophysics Data System (ADS)

    Wu, Yongpeng; Wen, Shipeng; Shen, Jing; Jiang, Jian; Hu, Shui; Zhang, Liqun; Liu, Li

    2015-06-01

    In this work, carbon black particles (CBs) were modified by high-energy electron beam (EB) irradiation at different doses. The influence of EB irradiation on the surface and particle size of CBs was investigated. Then, the CBs were compounded with natural rubber (NR), and the mechanical properties and dynamic properties of CBs/NR composite were further researched. The results showed that the irradiated CBs had more oxygen-containing groups and smaller particle sizes than original CBs. After irradiation, the content of bound rubber around the irradiated CBs increased, and the mechanical properties of CBs/NR composite were improved. Most importantly, NR filled with irradiated CBs has lower abrasion, higher wet skid resistance, and lower rolling resistance than NR filled with untreated CBs.

  4. Specific properties improvement of polycarbonate induced by irradiation at elevated particular temperature

    NASA Astrophysics Data System (ADS)

    Tang, Zhongfeng; Youshuang, Chen; Mouhua, Wang

    2014-03-01

    The properties and structures of polycarbonate (PC) changed by electron beam irradiation at the glass transition temperature (Tg) were investigated using the various measurements as thermal analysis, X-ray diffraction (XRD), and mechanical tests (tensile, hardness, wear, and impact properties). The Tg of irradiated PC sheets increases around 10 kGy, then decreases at high doses. Meanwhile, the ordered structure in the amorphous phase of samples was almost same up to 70 kGy by XRD. The wear resistance, hardness, and impact strength increased with dose and reached the maximum at around 10 kGy, then decreased at the higher doses. The tensile strength changed similar to impact strength, but the elongation at break decreased to the half at 10 kGy. The improvement of specific properties is explained to be dense molecular packing in matrix by re-arrangement of molecules with synergistic effects of radiation and thermal mobility via high temperature irradiation.

  5. Biaxial Stretch Improves Elastic Fiber Maturation, Collagen Arrangement, and Mechanical Properties in Engineered Arteries.

    PubMed

    Huang, Angela H; Balestrini, Jenna L; Udelsman, Brooks V; Zhou, Kevin C; Zhao, Liping; Ferruzzi, Jacopo; Starcher, Barry C; Levene, Michael J; Humphrey, Jay D; Niklason, Laura E

    2016-06-01

    Tissue-engineered blood vessels (TEVs) are typically produced using the pulsatile, uniaxial circumferential stretch to mechanically condition and strengthen the arterial grafts. Despite improvements in the mechanical integrity of TEVs after uniaxial conditioning, these tissues fail to achieve critical properties of native arteries such as matrix content, collagen fiber orientation, and mechanical strength. As a result, uniaxially loaded TEVs can result in mechanical failure, thrombus, or stenosis on implantation. In planar tissue equivalents such as artificial skin, biaxial loading has been shown to improve matrix production and mechanical properties. To date however, multiaxial loading has not been examined as a means to improve mechanical and biochemical properties of TEVs during culture. Therefore, we developed a novel bioreactor that utilizes both circumferential and axial stretch that more closely simulates loading conditions in native arteries, and we examined the suture strength, matrix production, fiber orientation, and cell proliferation. After 3 months of biaxial loading, TEVs developed a formation of mature elastic fibers that consisted of elastin cores and microfibril sheaths. Furthermore, the distinctive features of collagen undulation and crimp in the biaxial TEVs were absent in both uniaxial and static TEVs. Relative to the uniaxially loaded TEVs, tissues that underwent biaxial loading remodeled and realigned collagen fibers toward a more physiologic, native-like organization. The biaxial TEVs also showed increased mechanical strength (suture retention load of 303 ± 14.53 g, with a wall thickness of 0.76 ± 0.028 mm) and increased compliance. The increase in compliance was due to combinatorial effects of mature elastic fibers, undulated collagen fibers, and collagen matrix orientation. In conclusion, biaxial stretching is a potential means to regenerate TEVs with improved matrix production, collagen organization, and mechanical

  6. Two different electrical properties can improve transoceanic cable-route mapping

    USGS Publications Warehouse

    Wynn, J.; McGinnis, T.

    2001-01-01

    Induced polarization (IP) measurements made in the marine environment were investigated to map and remotely characterize the top 6-10 meters of the seafloor. The continuous resistivity profiling with cone-penetrometer tests, providing important information to engineers planning transoceanic cable routes, was also described. The IP effect and resistivity were identified as the two electric properties to improve transoceanic cable-route mapping. The measurement of IP and resistivity was found to depend on electrical current.

  7. Xylan-cellulose films: improvement of hydrophobicity, thermal and mechanical properties.

    PubMed

    Gordobil, Oihana; Egüés, Itziar; Urruzola, Iñaki; Labidi, Jalel

    2014-11-01

    Xylan-rich hemicellulose from corn cob has been used for new material elaboration. Commercial cellulose was used as reinforcement in different percentages to improve properties of the films. Two types of composites were elaborated by solvent casting. Hydrophilic films, composed by bleached hemicellulose (BH), unmodified cellulose and glycerol as plasticizer, and hydrophobic films formed by acetylated bleached hemicellulose (BAH) and acetylated cellulose. The degree of substitution of BAH was 1.8 and acetylated cellulose presented a degree of substitution of 0.54. Thermal and mechanical properties of films were analyzed. A significant improvement was observed in the thermal behavior of hydrophobic films (Tmax ∼ 368 °C) respect to hydrophilic films (Tmax ∼ 300 °C). Although the addition of cellulose clearly increase the properties of both type of films, hydrophobic films (Young's modulus ∼ 2300 MPa, strength ∼ 44.1MPa, strain at break ∼ 5.7%) showed better mechanical properties than hydrophilic films (Young's modulus ∼ 3 MPa, strength ∼ 3.3 MPa, strain at break ∼ 5.3%). PMID:25129716

  8. Ferrocene Containing Copolymers with Improved Electrostatic Dissipation Properties for Advanced Applications

    NASA Technical Reports Server (NTRS)

    Smith, T. M.; Nelson, G. L.

    2005-01-01

    Electrostatic dissipative polymers are used for a variety of functions. Typical methods utilized to transform electrically insulating polymers into either charge dissipative or conductive materials involve incorporating a conductive filler, conductive polymer, oxidizing the surface using plasma, or incorporating surfactants that act as surface wetting agents. Another approach is to synthesize a block copolymer that is expected to result in better electrical properties with minimal impacts to physical, fire, and thermal properties. One such block that can be added into the main chain of polymers is a diol terminated ferrocene oligomer, which is expected to impart electrostatic dissipative properties into the host polymer while concurrently improving the overall fire properties. Previous work with polyurethanes incorporating a ferrocene oligomer into the main chain resulted in much improved fire retardancy. In dealing with electrostatic dissipative materials the important questions are: how easily does the material charge and how quickly can the charge move to ground. One normally describes the materials conductivity, but conductivity only measures the fastest path for an electron not the slowest path. The slowest path is the one of interest, since it is left on the surface and thus can cause discharges. In order to assess ease of charging and decay times corona charge dissipation measurements can accurately assess these properties by introducing a charge on the surface of the material then measuring the surface voltage and the amount of charge deposited. The charge decay curve then will give an indication of a materials electrostatic dissipation properties. Normally, triboelectric testing can be performed, but results vary. Corona charge dissipation results are more repeatable.

  9. Improvements of Thermal, Mechanical, and Water-Resistance Properties of Polybenzoxazine/Boron Carbide Nanocomposites

    NASA Astrophysics Data System (ADS)

    Ramdani, Noureddine; Derradji, Mehdi; Wang, Jun; Mokhnache, El-Oualid; Liu, Wen-Bin

    2016-07-01

    Novel kinds of nanocomposites based on bisphenol A-aniline based polybenzoxazine matrix P(BA-a) and 0 wt.%-20 wt.% boron carbide (B4C) nanoparticles were produced and their properties were evaluated in terms of the nano-B4C content. The thermal conductivity of the P(BA-a) matrix was improved approximately three times from 0.18 W/m K to 0.86 W/m K at 20 wt.% nano-B4C loading, while its coefficient of thermal expansion (CTE) was deceased by 47% with the same nanofiller content. The microhardness properties were significantly improved by adding the B4C nanoparticles. At 20 wt.% of nano-B4C content, dynamic mechanical analysis (DMA) revealed a marked increase in the storage modulus and the glass transition temperature (T g) of the nanocomposites, reaching 3.9 GPa and 204°C, respectively. Hot water uptake tests showed that the water-resistance of the polybenzoxazine matrix was increased by filling with nano-B4C nano-filler. The morphological analysis reflected that the improvements obtained in the mechanical and thermal properties are related to the uniform dispersion of the nano-B4C particles and their strong adhesion to the P(BA-a) matrix.

  10. Improvements of Thermal, Mechanical, and Water-Resistance Properties of Polybenzoxazine/Boron Carbide Nanocomposites

    NASA Astrophysics Data System (ADS)

    Ramdani, Noureddine; Derradji, Mehdi; Wang, Jun; Mokhnache, El-Oualid; Liu, Wen-Bin

    2016-09-01

    Novel kinds of nanocomposites based on bisphenol A-aniline based polybenzoxazine matrix P(BA-a) and 0 wt.%-20 wt.% boron carbide (B4C) nanoparticles were produced and their properties were evaluated in terms of the nano-B4C content. The thermal conductivity of the P(BA-a) matrix was improved approximately three times from 0.18 W/m K to 0.86 W/m K at 20 wt.% nano-B4C loading, while its coefficient of thermal expansion (CTE) was deceased by 47% with the same nanofiller content. The microhardness properties were significantly improved by adding the B4C nanoparticles. At 20 wt.% of nano-B4C content, dynamic mechanical analysis (DMA) revealed a marked increase in the storage modulus and the glass transition temperature ( T g) of the nanocomposites, reaching 3.9 GPa and 204°C, respectively. Hot water uptake tests showed that the water-resistance of the polybenzoxazine matrix was increased by filling with nano-B4C nano-filler. The morphological analysis reflected that the improvements obtained in the mechanical and thermal properties are related to the uniform dispersion of the nano-B4C particles and their strong adhesion to the P(BA-a) matrix.

  11. Assimilation of remotely-sensed optical properties to improve marine biogeochemistry modelling

    NASA Astrophysics Data System (ADS)

    Ciavatta, Stefano; Torres, Ricardo; Martinez-Vicente, Victor; Smyth, Timothy; Dall'Olmo, Giorgio; Polimene, Luca; Allen, J. Icarus

    2014-09-01

    In this paper we evaluate whether the assimilation of remotely-sensed optical data into a marine ecosystem model improves the simulation of biogeochemistry in a shelf sea. A localized Ensemble Kalman filter was used to assimilate weekly diffuse light attenuation coefficient data, Kd(443) from SeaWiFs, into an ecosystem model of the western English Channel. The spatial distributions of (unassimilated) surface chlorophyll from satellite, and a multivariate time series of eighteen biogeochemical and optical variables measured in situ at one long-term monitoring site were used to evaluate the system performance for the year 2006. Assimilation reduced the root mean square error and improved the correlation with the assimilated Kd(443) observations, for both the analysis and, to a lesser extent, the forecast estimates, when compared to the reference model simulation. Improvements in the simulation of (unassimilated) ocean colour chlorophyll were less evident, and in some parts of the Channel the simulation of this data deteriorated. The estimation errors for the (unassimilated) in situ data were reduced for most variables with some exceptions, e.g. dissolved nitrogen. Importantly, the assimilation adjusted the balance of ecosystem processes by shifting the simulated food web towards the microbial loop, thus improving the estimation of some properties, e.g. total particulate carbon. Assimilation of Kd(443) outperformed a comparative chlorophyll assimilation experiment, in both the estimation of ocean colour data and in the simulation of independent in situ data. These results are related to relatively low error in Kd(443) data, and because it is a bulk optical property of marine ecosystems. Assimilation of remotely-sensed optical properties is a promising approach to improve the simulation of biogeochemical and optical variables that are relevant for ecosystem functioning and climate change studies.

  12. Nanocrystalline CuNi alloys: improvement of mechanical properties and thermal stability

    NASA Astrophysics Data System (ADS)

    Nogues, Josep; Varea, A.; Pellicer, E.; Sivaraman, K. M.; Pane, S.; Nelson, B. J.; Surinach, S.; Baro, M. D.; Sort, J.

    2014-03-01

    Nanocrystalline metallic films are known to benefit from novel and enhanced physical and chemical properties. In spite of these outstanding properties, nanocrystalline metals typically show relatively poor thermal stability which leads to deterioration of the properties due to grain coarsening. We have studied nanocrystalline Cu1-xNix (0.56 < x < 1) thin films (3 μm-thick) electrodeposited galvanostatically onto Cu/Ti/Si (100) substrates. CuNi thin films exhibit large values of hardness (6.15 < H < 7.21 GPa), which can be tailored by varying the composition. However, pure Ni films (x = 1) suffer deterioration of their mechanical and magnetic properties after annealing during 3 h at relatively low temperatures (TANN > 475 K) due to significant grain growth. Interestingly, alloying Ni with Cu clearly improves the thermal stability of the material because grain coarsening is delayed due to segregation of a Cu-rich phase at grain boundaries, thus preserving both the mechanical and magnetic properties up to higher TANN.

  13. Plasma treatment of electrospun PCL random nanofiber meshes (NFMs) for biological property improvement.

    PubMed

    Yan, D; Jones, J; Yuan, X Y; Xu, X H; Sheng, J; Lee, J C-M; Ma, G Q; Yu, Q S

    2013-04-01

    In this article, the plasma surface modification effects on the chemical, mechanical, and biological properties of electrospun poly (ε-caprolactone) (PCL) random nanofiber meshes (NFMs) were investigated by adjusting plasma chemistry, that is, using glow discharges of N(2) +H(2), NH(3) +O(2), and Ar+O(2) gas mixtures. The surface property changes of electrospun PCL NFMs after those plasma treatments were examined by water contact angle measurements and X-ray photoelectron spectroscopy. The experimental results showed that the plasma treatments introduced polar groups onto the surfaces and thus increased the surface hydrophilicity. From tensile test data, plasma treatment had limited effect on the mechanical properties of PCL random NFMs. The biological properties of the plasma-treated PCL NFMs were examined by cell proliferation assays using mouse osteoblast cells (MC3T3-E1). It was found that the plasma-treated PCL NFMs gave a higher proliferation rate and improved cell adhesion properties as compared with the untreated controls. PMID:22965926

  14. Carbon-Encapsulated Hollow Porous Vanadium-Oxide Nanofibers for Improved Lithium Storage Properties.

    PubMed

    An, Geon-Hyoung; Lee, Do-Young; Ahn, Hyo-Jin

    2016-08-01

    Carbon-encapsulated hollow porous vanadium-oxide (C/HPV2O5) nanofibers have been fabricated using electrospinning and postcalcination. By optimized postcalcination of vanadium-nitride and carbon-nanofiber composites at 400 °C for 30 min, we synthesized a unique architecture electrode with interior void spaces and well-defined pores as well as a uniform carbon layer on the V2O5 nanofiber surface. The optimized C/HPV2O5 electrode postcalcined at 400 °C for 30 min showed improved lithium storage properties with high specific discharge capacities, excellent cycling durability (241 mA h g(-1) at 100 cycles), and improved high-rate performance (155 mA h g(-1) at 1000 mA g(-1)), which is the highest performance in comparison with previously reported V2O5-based cathode materials. The improved electrochemical feature is due to the attractive properties of the carbon-encapsulated hollow porous structure: (I) excellent cycling durability with high specific capacity relative to the adoption of carbon encapsulation as a physical buffer layer and the effective accommodation of volume changes due to the hollow porous structure, (II) improved high-rate performance because of a shorter Li-ion diffusion pathway resulting from interior void spaces and well-defined pores at the surface. This unique electrode structure can potentially provide new cathode materials for high-performance lithium-ion batteries.

  15. Carbon-Encapsulated Hollow Porous Vanadium-Oxide Nanofibers for Improved Lithium Storage Properties.

    PubMed

    An, Geon-Hyoung; Lee, Do-Young; Ahn, Hyo-Jin

    2016-08-01

    Carbon-encapsulated hollow porous vanadium-oxide (C/HPV2O5) nanofibers have been fabricated using electrospinning and postcalcination. By optimized postcalcination of vanadium-nitride and carbon-nanofiber composites at 400 °C for 30 min, we synthesized a unique architecture electrode with interior void spaces and well-defined pores as well as a uniform carbon layer on the V2O5 nanofiber surface. The optimized C/HPV2O5 electrode postcalcined at 400 °C for 30 min showed improved lithium storage properties with high specific discharge capacities, excellent cycling durability (241 mA h g(-1) at 100 cycles), and improved high-rate performance (155 mA h g(-1) at 1000 mA g(-1)), which is the highest performance in comparison with previously reported V2O5-based cathode materials. The improved electrochemical feature is due to the attractive properties of the carbon-encapsulated hollow porous structure: (I) excellent cycling durability with high specific capacity relative to the adoption of carbon encapsulation as a physical buffer layer and the effective accommodation of volume changes due to the hollow porous structure, (II) improved high-rate performance because of a shorter Li-ion diffusion pathway resulting from interior void spaces and well-defined pores at the surface. This unique electrode structure can potentially provide new cathode materials for high-performance lithium-ion batteries. PMID:27404906

  16. Molecular level materials design for improvements of actuation properties of dielectric elastomer actuators

    NASA Astrophysics Data System (ADS)

    Kofod, G.; Stoyanov, H.; Kollosche, M.; Risse, S.; Ragusch, H.; McCarthy, D. N.; Waché, R.; Rychkov, D.; Dansachmüller, M.

    2011-04-01

    Dielectric elastomer actuators are soft electro-mechanical transducers with possible uses in robotic, orthopaedic and automotive applications. The active material must be soft and have a high ability to store electrical energy. Hence, three properties of the elastic medium in a dielectric elastomer actuator affect the actuation properties directly: dielectric constant, electric breakdown strength, and mechanical stiffness. The dielectric constant of a given elastomer can be improved by mixing it with other components with a higher dielectric constant, which can be classified as insulating or conducting. In this paper, an overview of all approaches proposed so far for dielectric constant improvement in these soft materials will be provided. Insulating particles such as TiO2 nanoparticles can raise the dielectric constant, but may also lead to stiffening of the composite, such that the overall actuation is lowered. It is shown here how a chemical coating of the TiO2 nanoparticles leads to verifiable improvements. Conducting material can also lead to improvements, as has been shown in several cases. Simple percolation, relying on the random distribution of conducting nanoparticles, commonly leads to drastic lowering of the breakdown strength. On the other hand, conducting polymer can also be employed, as has been demonstrated. We show here how an approach based on a specific chemical reaction between the conducting polymer and the elastomer network molecules solves the problem of premature breakdown which is otherwise typically found.

  17. Reducing pharmaceutical risk.

    PubMed

    Spilker, B

    1998-08-01

    This article describes several types of risk encountered in drug discovery, development and marketing, as well as the overall business risks in the pharmaceutical industry. Discovery risk refers to the risk companies face if they are partly or totally dependent on discovering new drugs; many avenues are presented for companies to pursue in order to decrease discovery risk. Development risk is defined as the risk that drug discoveries that enter development will not reach the market and become commercially viable drugs. To decrease development risk, it is possible to pursue one or more of the approaches presented. Significant marketing risks for a company include that the sales forecasts will not be met, the positioning of a drug may not be correct or optimal and the sales force is not performing adequately. At the corporate level there are numerous major risks involved in pursuing the specific mission, objectives, strategies and tactics of the overall company as well as those in the functional areas. Many aspects of the company's business can be adjusted or changed to decrease corporate risk. Selected issues concerning risk include venture capital funds, the appetite for risk within a company and the influence of senior and middle level managers' personalities on risk.

  18. Reducing pharmaceutical risk.

    PubMed

    Spilker, B

    1998-08-01

    This article describes several types of risk encountered in drug discovery, development and marketing, as well as the overall business risks in the pharmaceutical industry. Discovery risk refers to the risk companies face if they are partly or totally dependent on discovering new drugs; many avenues are presented for companies to pursue in order to decrease discovery risk. Development risk is defined as the risk that drug discoveries that enter development will not reach the market and become commercially viable drugs. To decrease development risk, it is possible to pursue one or more of the approaches presented. Significant marketing risks for a company include that the sales forecasts will not be met, the positioning of a drug may not be correct or optimal and the sales force is not performing adequately. At the corporate level there are numerous major risks involved in pursuing the specific mission, objectives, strategies and tactics of the overall company as well as those in the functional areas. Many aspects of the company's business can be adjusted or changed to decrease corporate risk. Selected issues concerning risk include venture capital funds, the appetite for risk within a company and the influence of senior and middle level managers' personalities on risk. PMID:15616620

  19. Prioritizing pharmaceuticals in municipal wastewater

    EPA Science Inventory

    Oral presentation at SETAC North America 32nd annual meeting, describing our prioritization of active pharmaceutical ingredients (APIs), based on estimates of risks posed by API residues originating from municipal wastewater. Goals of this project include prioritization of APIs f...

  20. Metalcone Chemistry: In pursuit of improved mechanical properties in thin film deposition

    NASA Astrophysics Data System (ADS)

    Hall, Robert A.

    Atomic Layer Deposition (ALD) and its subset, Molecular layer deposition (MLD), is a thin film deposition technique using alternating self-limiting precursors to grow thin films on a substrates. Recent research has expanded MLD to use reactive metal alkyls/halides and organic fragments containing alcohol groups such as ethylene glycol for use in protective barriers. Unfortunately using ethylene glycol as a precursor causes film stability issues and does not provide adequate mechanical properties for projected uses. The current research looks into the investigation of using different metal alkyls and metal halides with the trifunctional precursor glycerol. The three main films investigated were the AlGL using trimethylaluminum and glycerol, ZnGL using diethyl zinc and glycerol and TIGL using titanium (IV) chloride and glycerol. The films were investigated using quartz crystal microbalance, X-ray reflectivity, and spectroscopic ellipsometry for characterization of their film growth. All films exhibited linear growth at a range of temperatures above 130°C with AlGL, ZnGL and TiGL displaying a growth rate at 150°C of ˜2.34A/cycle, ˜1.29A/cycle, and ˜2.2A/cycle respectfully. Initially film growth was investigated in situ using quartz crystal microbalance and then the growth rates confirmed ex situ using X-ray reflectivity. Once the film growth and mechanism were investigated, the mechanical properties were investigated to determine if there was an improvement in cross-linking in the films. The mechanical properties of these MLD films were also investigated using a mechanical testing system and nanoindenter. The mechanical properties for AlGL and ZnGL showed a large improvement from 0.69% to 1.2% for their critical tensile strain compared to previous MLD films. The films also showed an increase in mechanical properties from their nanoindentation results consistent with an increase in cross-linking.

  1. Globalization in the pharmaceutical industry, Part II.

    PubMed

    Casadio Tarabusi, C; Vickery, G

    1998-01-01

    This is the second of a two-part report on the pharmaceutical industry. Part II begins with a discussion of foreign direct investment and inter-firm networks, which covers international mergers, acquisitions, and minority participation; market shares of foreign-controlled firms; international collaboration agreements (with a special note on agreements in biotechnology); and licensing agreements. The final section of the report covers governmental policies on health and safety regulation, price regulation, industry and technology, trade, foreign investment, protection of intellectual property, and competition. PMID:9595345

  2. What drives success for specialty pharmaceuticals?

    PubMed

    Gudiksen, Mark; Fleming, Edd; Furstenthal, Laura; Ma, Philip

    2008-07-01

    Specialty pharmaceuticals have become increasingly important in the global pharmaceutical landscape. Numerous large pharmaceutical companies are moving towards developing therapies for specialty markets, which are attractive owing to factors including the established commercial track record and lower commercial infrastructure costs. In this article, we analyse the key drivers of commercial success and failure for specialty pharmaceuticals.

  3. Dropwise additive manufacturing of pharmaceutical products for solvent-based dosage forms.

    PubMed

    Hirshfield, Laura; Giridhar, Arun; Taylor, Lynne S; Harris, Michael T; Reklaitis, Gintaras V

    2014-02-01

    In recent years, the US Food and Drug Administration has encouraged pharmaceutical companies to develop more innovative and efficient manufacturing methods with improved online monitoring and control. Mini-manufacturing of medicine is one such method enabling the creation of individualized product forms for each patient. This work presents dropwise additive manufacturing of pharmaceutical products (DAMPP), an automated, controlled mini-manufacturing method that deposits active pharmaceutical ingredients (APIs) directly onto edible substrates using drop-on-demand (DoD) inkjet printing technology. The use of DoD technology allows for precise control over the material properties, drug solid state form, drop size, and drop dynamics and can be beneficial in the creation of high-potency drug forms, combination drugs with multiple APIs or individualized medicine products tailored to a specific patient. In this work, DAMPP was used to create dosage forms from solvent-based formulations consisting of API, polymer, and solvent carrier. The forms were then analyzed to determine the reproducibility of creating an on-target dosage form, the morphology of the API of the final form and the dissolution behavior of the drug over time. DAMPP is found to be a viable alternative to traditional mass-manufacturing methods for solvent-based oral dosage forms.

  4. Quantitative on-line preconcentration-liquid chromatography coupled with tandem mass spectrometry method for the determination of pharmaceutical compounds in water.

    PubMed

    Idder, Salima; Ley, Laurent; Mazellier, Patrick; Budzinski, Hélène

    2013-12-17

    One of the current environmental issues concerns the presence and fate of pharmaceuticals in water bodies as these compounds may represent a potential environmental problem. The characterization of pharmaceutical contamination requires powerful analytical method able to quantify these pollutants at very low concentration (few ng L(-1)). In this work, a multi-residue analytical methodology (on-line solid phase extraction-liquid chromatography-triple quadrupole mass spectrometry using positive and negative electrospray ionization) has been developed and validated for 40 multi-class pharmaceuticals and metabolites for tap and surface waters. This on-line SPE method was very convenient and efficient compared to classical off-line SPE method because of its shorter total run time including sample preparation and smaller sample volume (1 mL vs up to 1 L). The optimized method included several therapeutic classes as lipid regulators, antibiotics, beta-blockers, non-steroidal anti-inflammatories, antineoplastic, etc., with various physicochemical properties. Quantification has been achieved with the internal standards. The limits of detection are between 0.7 and 15 ng L(-1) for drinking waters and 2-15 ng L(-1) for surface waters. The inter-day precision values are below 20% for each studied level. The improvement and strength of the analytical method has been verified along a monitoring of these 40 pharmaceuticals in Isle River, a French stream located in the South West of France. During this survey, 16 pharmaceutical compounds have been detected.

  5. Elemental Impurities in Pharmaceutical Excipients.

    PubMed

    Li, Gang; Schoneker, Dave; Ulman, Katherine L; Sturm, Jason J; Thackery, Lisa M; Kauffman, John F

    2015-12-01

    Control of elemental impurities in pharmaceutical materials is currently undergoing a transition from control based on concentrations in components of drug products to control based on permitted daily exposures in drug products. Within the pharmaceutical community, there is uncertainty regarding the impact of these changes on manufactures of drug products. This uncertainty is fueled in part by a lack of publically available information on elemental impurity levels in common pharmaceutical excipients. This paper summarizes a recent survey of elemental impurity levels in common pharmaceutical excipients as well as some drug substances. A widely applicable analytical procedure was developed and was shown to be suitable for analysis of elements that are subject to United States Pharmacopoeia Chapter <232> and International Conference on Harmonization's Q3D Guideline on Elemental Impurities. The procedure utilizes microwave-assisted digestion of pharmaceutical materials and inductively coupled plasma mass spectrometry for quantitative analysis of these elements. The procedure was applied to 190 samples from 31 different excipients and 15 samples from eight drug substances provided through the International Pharmaceutical Excipient Council of the Americas. The results of the survey indicate that, for the materials included in the study, relatively low levels of elemental impurities are present. PMID:26398581

  6. Elemental Impurities in Pharmaceutical Excipients.

    PubMed

    Li, Gang; Schoneker, Dave; Ulman, Katherine L; Sturm, Jason J; Thackery, Lisa M; Kauffman, John F

    2015-12-01

    Control of elemental impurities in pharmaceutical materials is currently undergoing a transition from control based on concentrations in components of drug products to control based on permitted daily exposures in drug products. Within the pharmaceutical community, there is uncertainty regarding the impact of these changes on manufactures of drug products. This uncertainty is fueled in part by a lack of publically available information on elemental impurity levels in common pharmaceutical excipients. This paper summarizes a recent survey of elemental impurity levels in common pharmaceutical excipients as well as some drug substances. A widely applicable analytical procedure was developed and was shown to be suitable for analysis of elements that are subject to United States Pharmacopoeia Chapter <232> and International Conference on Harmonization's Q3D Guideline on Elemental Impurities. The procedure utilizes microwave-assisted digestion of pharmaceutical materials and inductively coupled plasma mass spectrometry for quantitative analysis of these elements. The procedure was applied to 190 samples from 31 different excipients and 15 samples from eight drug substances provided through the International Pharmaceutical Excipient Council of the Americas. The results of the survey indicate that, for the materials included in the study, relatively low levels of elemental impurities are present.

  7. CSI-EPT: A Contrast Source Inversion Approach for Improved MRI-Based Electric Properties Tomography.

    PubMed

    Balidemaj, Edmond; van den Berg, Cornelis A T; Trinks, Johan; van Lier, Astrid L H M W; Nederveen, Aart J; Stalpers, Lukas J A; Crezee, Hans; Remis, Rob F

    2015-09-01

    Electric properties tomography (EPT) is an imaging modality to reconstruct the electric conductivity and permittivity inside the human body based on B1(+) maps acquired by a magnetic resonance imaging (MRI) system. Current implementations of EPT are based on the local Maxwell equations and assume piecewise constant media. The accuracy of the reconstructed maps may therefore be sensitive to noise and reconstruction errors occur near tissue boundaries. In this paper, we introduce a multiplicative regularized CSI-EPT method (contrast source inversion-electric properties tomography) where the electric tissue properties are retrieved in an iterative fashion based on a contrast source inversion approach. The method takes the integral representations for the electromagnetic field as a starting point and the tissue parameters are obtained by iteratively minimizing an objective function which measures the discrepancy between measured and modeled data and the discrepancy in satisfying a consistency equation known as the object equation. Furthermore, the objective function consists of a multiplicative Total Variation factor for noise suppression during the reconstruction process. Finally, the presented implementation is able to simultaneously include more than one B1(+) data set acquired by complementary RF excitation settings. We have performed in vivo simulations using a female pelvis model to compute the B1(+) fields. Three different RF excitation settings were used to acquire complementary B1(+) fields for an improved overall reconstruction. Numerical results illustrate the improved reconstruction near tissue boundaries and the ability of CSI-EPT to reconstruct small tissue structures. PMID:25706578

  8. Improved antifouling properties of polyamide nanofiltration membranes by reducing the density of surface carboxyl groups.

    PubMed

    Mo, Yinghui; Tiraferri, Alberto; Yip, Ngai Yin; Adout, Atar; Huang, Xia; Elimelech, Menachem

    2012-12-18

    Carboxyls are inherent functional groups of thin-film composite polyamide nanofiltration (NF) membranes, which may play a role in membrane performance and fouling. Their surface presence is attributed to incomplete reaction of acyl chloride monomers during the membrane active layer synthesis by interfacial polymerization. In order to unravel the effect of carboxyl group density on organic fouling, NF membranes were fabricated by reacting piperazine (PIP) with either isophthaloyl chloride (IPC) or the more commonly used trimesoyl chloride (TMC). Fouling experiments were conducted with alginate as a model hydrophilic organic foulant in a solution, simulating the composition of municipal secondary effluent. Improved antifouling properties were observed for the IPC membrane, which exhibited lower flux decline (40%) and significantly greater fouling reversibility or cleaning efficiency (74%) than the TMC membrane (51% flux decline and 40% cleaning efficiency). Surface characterization revealed that there was a substantial difference in the density of surface carboxyl groups between the IPC and TMC membranes, while other surface properties were comparable. The role of carboxyl groups was elucidated by measurements of foulant-surface intermolecular forces by atomic force microscopy, which showed lower adhesion forces and rupture distances for the IPC membrane compared to TMC membranes in the presence of calcium ions in solution. Our results demonstrated that a decrease in surface carboxyl group density of polyamide membranes fabricated with IPC monomers can prevent calcium bridging with alginate and, thus, improve membrane antifouling properties. PMID:23205860

  9. Development of Problem Sets for K-12 and Engineering on Pharmaceutical Particulate Systems

    ERIC Educational Resources Information Center

    Savelski, Mariano J.; Slater, C. Stewart; Del Vecchio, Christopher A.; Kosteleski, Adrian J.; Wilson, Sarah A.

    2010-01-01

    Educational problem sets have been developed on structured organic particulate systems (SOPS) used in pharmaceutical technology. The sets present topics such as particle properties and powder flow and can be integrated into K-12 and college-level curricula. The materials educate students in specific areas of pharmaceutical particulate processing,…

  10. Improved Estimation of Orbits and Physical Properties of Objects in GEO

    NASA Astrophysics Data System (ADS)

    Bradley, B.; Axelrad, P.

    2013-09-01

    Orbital debris is a major concern for satellite operators, both commercial and military. Debris in the geosynchronous (GEO) belt is of particular concern because this unique region is such a valuable, limited resource, and, from the ground we cannot reliably track and characterize GEO objects smaller than 1 meter in diameter. Space-based space surveillance (SBSS) is required to observe GEO objects without weather restriction and with improved viewing geometry. SBSS satellites have thus far been placed in Sun-synchronous orbits. This paper investigates the benefits to GEO orbit determination (including the estimation of mass, area, and shape) that arises from placing observing satellites in geosynchronous transfer orbit (GTO) and a sub-GEO orbit. Recently, several papers have reported on simulation studies to estimate orbits and physical properties; however, these studies use simulated objects and ground-based measurements, often with dense and long data arcs. While this type of simulation provides valuable insight into what is possible, as far as state estimation goes, it is not a very realistic observing scenario and thus may not yield meaningful accuracies. Our research improves upon simulations published to date by utilizing publicly available ephemerides for the WAAS satellites (Anik F1R and Galaxy 15), accurate at the meter level. By simulating and deliberately degrading right ascension and declination observations, consistent with these ephemerides, a realistic assessment of the achievable orbit determination accuracy using GTO and sub-GEO SBSS platforms is performed. Our results show that orbit accuracy is significantly improved as compared to a Sun-synchronous platform. Physical property estimation is also performed using simulated astrometric and photometric data taken from GTO and sub-GEO sensors. Simulations of SBSS-only as well as combined SBSS and ground-based observation tracks are used to study the improvement in area, mass, and shape estimation

  11. Hybrid systems based on "drug - in cyclodextrin - in nanoclays" for improving oxaprozin dissolution properties.

    PubMed

    Mura, Paola; Maestrelli, Francesca; Aguzzi, Carola; Viseras, César

    2016-07-25

    A combined approach based on drug complexation with cyclodextrins, and complex entrapment in nanoclays has been investigated, to join in a single delivery system the benefits of these carriers and potentiate their ability to improve the dissolution properties of oxaprozin (OXA), a poorly water-soluble anti-inflammatory drug. Based on previous studies, randomly methylated ß-cyclodextrin (RAMEB) was chosen as the most effective cyclodextrin for OXA complexation. Adsorption equilibrium studies performed on three different clays (sepiolite, attapulgite, bentonite) allowed selection of sepiolite (SV) for its greater adsorption power towards OXA. DSC and XRPD studies indicated drug amorphization in both binary OXA-RAMEB coground and OXA-SV cofused products, due to its complexation or very fine dispersion in the clay structure, respectively. The drug amorphous state was maintained also in the ternary OXA-RAMEB-SV cofused system. Dissolution studies evidenced a clear synergistic effect of RAMEB complexation and clay nanoencapsulation in improving the OXA dissolution properties, with an almost 100% increase in percent dissolved and dissolution efficiency compared to the OXA-RAMEB coground system. Therefore, the proposed combined approach represents an interesting tool for improving the therapeutic effectiveness of poorly soluble drugs, and reducing the CD amount necessary for obtaining the desired drug solubility and dissolution rate increase. PMID:27188644

  12. Improving wet and dry strength properties of recycled old corrugated carton (OCC) pulp using various polymers.

    PubMed

    Hamzeh, Yahya; Sabbaghi, Sanaz; Ashori, Alireza; Abdulkhani, Ali; Soltani, Farshid

    2013-04-15

    In this study, the application of different dosages of low and high molecular weights (MW) of chitosan (Ch), cationic starch (CS) and poly vinyl alcohol (PVA) were systematically investigated using old corrugated carton (OCC) furnishes. Various sequences of above-mentioned polymeric additives were also examined to find out the optimal combination for improving both wet and dry tensile strength. For each treatment, 4 handsheets, each having basis weight of 100 g/m(2), were made. In general, the tensile strength of handsheets was significantly affected by the addition of polymeric agents. The enhancing effect of additives on dry tensile property was much higher than wet condition. The results also showed that the tensile strength of the samples made from OCC furnishes were improved upon the addition of high molecular weight chitosan (ChI) compared to the untreated ones (control). The low MW chitosan did not change the properties of handsheets dramatically. Application of polymeric agents moderately decreased the stretch to rupture, however with increasing dosage the stretch was improved. Sequential addition of used polymers showed that triple application of polymers was beneficial to both dry and wet tensile strength, although the effect was larger for dry. The best results in wet and dry tensile strengths were achieved using sequential of PVA-ChI-CS. Sequential addition of oppositely charged polymers forms a macromolecular layered structure of polyelectrolytes. PMID:23544577

  13. Cross-linked chitosan improves the mechanical properties of calcium phosphate-chitosan cement

    PubMed Central

    Aryaei, Ashkan; Liu, Jason; Jayatissa, Ahalapitiya. H.; Jayasuriya, A. Champa

    2015-01-01

    Calcium phosphate (CaP) cements are highly applicable and valuable materials for filling bone defects by minimally invasive procedures. Chitosan (CS) biopolymer is also considered as one of the promising biomaterial candidates in bone tissue engineering. In the present study, some key features of CaP-CS were significantly improved by developing a novel CaP-CS composite. For this purpose, CS was the first cross-linked with tripolyphosphate (TPP) and then mixed with CaP matrix. A group of CaP-CS samples without cross-linking was also prepared. Samples were fabricated and tested based on the known standards. Additionally, the effect of different powder (P) to liquid (L) ratios was also investigated. Both cross-linked and uncross-linked CaP-CS samples showed excellent washout resistance. The most significant effects were observed on Young's modulus and compressive strength in wet condition as well as surface hardness. In dry conditions, the Young's modulus of cross-linked samples were slightly improved. Based on the presented results, cross-linking does not have significant effect on porosity. As expected, by increasing the P/L ratio of sample, ductility and injectabilty were decreased. However, in the most cases, mechanical properties were enhanced. The results have shown that cross-linking can be improved the mechanical properties of CaP-CS and hence it can be used for bone tissue engineering applications. PMID:26046262

  14. Effects of Constituent Properties on Performance Improvement of a Quenching and Partitioning Steel

    SciTech Connect

    Choi, Kyoo Sil; Hu, Xiaohua; Sun, Xin; Taylor, Mark D.; De Moor, Emmanuel; Speer, John; Matlock, David K.

    2014-04-01

    In this paper, a two-dimensional microstructure-based finite element modeling method is adopted to investigate the effects of material parameters of the constituent phases on the macroscopic tensile behavior of Q&P steel and then to do a computational materials design approach for its performance improvement. For this purpose, a model Q&P steel is first produced and various experiments are then performed to characterize the steel. Actual microstructure-based model is generated based on the information from EBSD, SEM and nano-indentation test, and the material properties for the constituent phases are determined based on the initial constituents’ properties from HEXRD test and the subsequent calibration of model prediction to tensile test results. Influence of various material parameters of the constituents on the macroscopic behaviors is then investigated by separately adjusting them by small amount. Based on the observation on the respective influence of constituents’ material parameters, a new set of material parameters are devised, which results in better performance in ductility. The results indicate that various material parameters may need to be concurrently adjusted in a cohesive way in order to improve the performance of Q&P steel. In summary, higher austenite stability, less strength difference between the phases, higher hardening exponents of the phases are generally beneficial for the performance improvement. The information from this study can be used to devise new Q&P heat-treating parameters to produce the Q&P steels with better performance.

  15. Using Liquid Smoke to Improve Mechanical and Water Resistance Properties of Gelatin Films.

    PubMed

    Wang, Wenwang; Li, Cong; Zhang, Hongjie; Ni, Yonghao

    2016-05-01

    Improvement of mechanical and water barrier properties is critical for gelatin films when applied to edible food packaging. A liquid smoke (LS) obtained from hawthorn nucleus was used to improve the performance of gelatin film based on its abundant compounds. Through SPME-GC-MS analysis, 86 volatile and semi-volatile chemical compounds was detected in LS, in which the total carbonyl compounds were 27.60%, with the main aldehyde as 2-furaldehyde (9.83%). For gelatin films, an observable influence of LS on film transparency was observed in gelatin films, but not for its thickness and microstructure. Desirably, adding LS into gelatin solution increased the tensile strength of the films, with a better value of 16.38 MPa as 3 wt% LS added, compared with the control (10.30 MPa). Accordingly, film elongation decreased with a LS dependent manner. Furthermore, the water resistance properties of gelatin film were improved by the LS addition, which was supported by the results of water contact angle, water vapor permeability. Moreover, the addition of LS also led to a higher insolubility for gelatin films. Also, thermal stability of the LS treated gelatin films was slightly enhanced with the DSC analysis. According to the FTIR spectra and crosslinking degree detection results, all the above enhancing of gelatin film should be attributed to the crosslinking between carbonyl groups in LS and amide functionalities in gelatin based on nucleophilic reaction. PMID:27061211

  16. Using Liquid Smoke to Improve Mechanical and Water Resistance Properties of Gelatin Films.

    PubMed

    Wang, Wenwang; Li, Cong; Zhang, Hongjie; Ni, Yonghao

    2016-05-01

    Improvement of mechanical and water barrier properties is critical for gelatin films when applied to edible food packaging. A liquid smoke (LS) obtained from hawthorn nucleus was used to improve the performance of gelatin film based on its abundant compounds. Through SPME-GC-MS analysis, 86 volatile and semi-volatile chemical compounds was detected in LS, in which the total carbonyl compounds were 27.60%, with the main aldehyde as 2-furaldehyde (9.83%). For gelatin films, an observable influence of LS on film transparency was observed in gelatin films, but not for its thickness and microstructure. Desirably, adding LS into gelatin solution increased the tensile strength of the films, with a better value of 16.38 MPa as 3 wt% LS added, compared with the control (10.30 MPa). Accordingly, film elongation decreased with a LS dependent manner. Furthermore, the water resistance properties of gelatin film were improved by the LS addition, which was supported by the results of water contact angle, water vapor permeability. Moreover, the addition of LS also led to a higher insolubility for gelatin films. Also, thermal stability of the LS treated gelatin films was slightly enhanced with the DSC analysis. According to the FTIR spectra and crosslinking degree detection results, all the above enhancing of gelatin film should be attributed to the crosslinking between carbonyl groups in LS and amide functionalities in gelatin based on nucleophilic reaction.

  17. Mechanical properties improvement of silica aerogel through aging: Role of solvent type, time and temperature

    NASA Astrophysics Data System (ADS)

    Omranpour, H.; Dourbash, A.; Motahari, S.

    2014-05-01

    Effective parameters that enhance mechanical properties during aging were investigated in the present study. Silica aerogels were made from tetraethyl orthosilicate (TEOS), water, methanol and NH4F in molar ratio 1:4:8:2×10-3 using a one-step method. Different time, temperature and aging solvents in aging stage were studied. Subsequently, solvent exchange with n-hexane, modification under TMCS solution and ambient pressure drying (APD) were performed for all samples. The aerogels had densities within the range of 0.1 and 0.6 g/cm3. The FTIR, mechanical properties, density and BET results, porosity, pore volume, pore diameter and surface area of the samples, were discussed. The compression properties of the gel increased with the increase in the time and temperature of aging. It was observed that solvents with more polarity improved polymerization, which enhanced the mechanical properties of the related samples. However, the stresses and capillary forces of water during drying were so large that inhibited "spring-back effect" during APD, and consequently a collapsed silica network with higher density was fabricated. In other words, the specific compression strength and modulus declined drastically. For methanol, alcohols inhibit the reactions inconveniently causing more shrinkage. In aging by n-hexane, capillary pressure declined significantly and thereby shrinkage was eliminated and silica aerogels with low bulk densities (0.095 g/cm3), high specific surface areas (600 m2/g), and large pore volumes (2.6 cm3/g) were synthesized.

  18. Electronic structures and optical properties of TiO2: Improved density-functional-theory investigation

    NASA Astrophysics Data System (ADS)

    Gong, Sai; Liu, Bang-Gui

    2012-05-01

    TiO2 has been recently used to realize high-temperature ferromagnetic semiconductors. In fact, it has been widely used for a long time as white pigment and sunscreen because of its whiteness, high refractive index, and excellent optical properties. However, its electronic structures and the related properties have not been satisfactorily understood. Here, we use Tran and Blaha's modified Becke-Johnson (TB-mBJ) exchange potential (plus a local density approximation correlation potential) within the density functional theory to investigate electronic structures and optical properties of rutile and anatase TiO2. Our comparative calculations show that the energy gaps obtained from mBJ method agree better with the experimental results than that obtained from local density approximation (LDA) and generalized gradient approximation (GGA), in contrast with substantially overestimated values from many-body perturbation (GW) calculations. As for optical dielectric functions (both real and imaginary parts), refractive index, and extinction coefficients as functions of photon energy, our mBJ calculated results are in excellent agreement with the experimental curves. Our further analysis reveals that these excellent improvements are achieved because mBJ potential describes accurately the energy levels of Ti 3d states. These results should be helpful to understand the high temperature ferromagnetism in doped TiO2. This approach can be used as a standard to understand electronic structures and the related properties of such materials as TiO2.

  19. Improvement in mechanical and barrier properties of polyethylene blown films using atomic layer deposition

    SciTech Connect

    Lee, Gyeong Beom; Hak Song, Seung; Wook Moon, Sung; Woo Kim, Jun; Hyung Shim, Joon; Choi, Byoung-Ho; Moo Heo, Young

    2014-01-15

    Recently, thin films deposited on polymer substrates have been widely utilized as encapsulation barriers in electronic applications such as flexible displays, packaging films, and organic light-emitting diodes. The barrier and mechanical properties of these films are critical aspects when using them for protecting the inner modules of electronic devices from environmental factors such as moisture, oxygen, and sunlight. In particular, polymers can be degraded or decomposed more easily than other materials under such environmental conditions. Therefore, polymer films can be deposited using thin functional materials; however, suitable deposition methods for polymers are scarce owing to many limitations such as low melting/glass transition temperature, thermal degradation, and oxidation. In this study, a thin alumina oxide film was deposited on a high-density polyethylene blown film by using atomic layer deposition. The mechanical and barrier properties of the alumina oxide film deposited on the polyethylene film were characterized by a microtensile test and water vapor transmission rate test. Process conditions such as process temperature, plasma surface treatment, and number of cycles were varied to ascertain the reliability of the thin alumina oxide film deposited on the high-density polyethylene blown film. The results showed that the barrier property of the deposited film improved upon the application of plasma surface treatment, and that its mechanical properties varied under different process conditions.

  20. Optimal pultrusion process conditions for improving the dynamic properties of graphite-epoxy composite beams

    SciTech Connect

    Kowsika, M.V.S.L.N.; Mantena, P.R.

    1996-03-01

    The manufacturing process variables significantly influence the mechanical properties of pultruded composites. In this study, a statistical central composite design (CCD) test pattern has been used to manufacture unidirectional graphite-epoxy pultruded composite beams under carefully controlled process conditions. The influences of significant pultrusion process variables and their effects/interactions on the dynamic mechanical properties were investigated. The pultruded specimens were subjected to free vibration decay tests to determine nondestructively the dynamic flexural modulus and loss factor (a measure of internal damping). Mathematical models were derived based on the observed values of the dynamic properties using regression analysis procedures. These models were used to determine the optimal pultrusion process conditions for improving the dynamic mechanical properties of the finished product. A theoretical model postulating varying distribution of fiber content through the thickness of the pultruded composite is also presented. Static flexural tests and microscopic evaluation were employed to validate the assumption that a thin distinct layer of matrix material is formed on the outer surface of these pultruded products.

  1. Combined chemical treatment of pharmaceutical effluents from medical ointment production.

    PubMed

    Kulik, Niina; Trapido, Marina; Goi, Anna; Veressinina, Yelena; Munter, Rein

    2008-02-01

    Three wastewater samples from a pharmaceutical plant formulating medical ointments were subjected to lab-scale treatment by a Fenton-like system in combination with lime coagulation. All samples were plant pre-treated by adsorption/flocculation/filtration processes with utilization of bentonite, but the quality of effluents did not comply with the regulations for wastewater discharged to local sewerage. The optimization of Fenton-like oxidation demonstrated the highest process efficacy at H(2)O(2)/COD weight ratio of 2:1, H(2)O(2)/Fe(2+) molar ratio of 10:1 and 2h of treatment time. The fast pH decrease to acidic values approximately 3 during first min of oxidation for all effluents suggested that pH adjustment was unnecessary. Combination of Fe(III) precipitation and lime coagulation proved feasible to improve considerably COD and residual iron concentration reduction in pharmaceutical effluents. Additionally, considerable BOD(7) reduction and BOD(7)/COD ratio improvement of pharmaceutical wastewater samples was achieved by combined treatment. The application of Fenton-like oxidation with subsequent iron (III)/lime coagulation did not only enhance the quality of pharmaceutical effluents with different chemical characteristics and help to meet the requirements for wastewater discharged to sewage, but also improve the biodegradability of pharmaceutical effluents.

  2. Effects of Glycosylation on the Stability of Protein Pharmaceuticals

    PubMed Central

    SOLÁ, RICARDO J.; GRIEBENOW, KAI

    2008-01-01

    In recent decades, protein-based therapeutics have substantially expanded the field of molecular pharmacology due to their outstanding potential for the treatment of disease. Unfortunately, protein pharmaceuticals display a series of intrinsic physical and chemical instability problems during their production, purification, storage, and delivery that can adversely impact their final therapeutic efficacies. This has prompted an intense search for generalized strategies to engineer the long-term stability of proteins during their pharmaceutical employment. Due to the well known effect that glycans have in increasing the overall stability of glycoproteins, rational manipulation of the glycosylation parameters through glycoengineering could become a promising approach to improve both the in vitro and in vivo stability of protein pharmaceuticals. The intent of this review is therefore to further the field of protein glycoengineering by increasing the general understanding of the mechanisms by which glycosylation improves the molecular stability of protein pharmaceuticals. This is achieved by presenting a survey of the different instabilities displayed by protein pharmaceuticals, by addressing which of these instabilities can be improved by glycosylation, and by discussing the possible mechanisms by which glycans induce these stabilization effects. PMID:18661536

  3. Combined chemical treatment of pharmaceutical effluents from medical ointment production.

    PubMed

    Kulik, Niina; Trapido, Marina; Goi, Anna; Veressinina, Yelena; Munter, Rein

    2008-02-01

    Three wastewater samples from a pharmaceutical plant formulating medical ointments were subjected to lab-scale treatment by a Fenton-like system in combination with lime coagulation. All samples were plant pre-treated by adsorption/flocculation/filtration processes with utilization of bentonite, but the quality of effluents did not comply with the regulations for wastewater discharged to local sewerage. The optimization of Fenton-like oxidation demonstrated the highest process efficacy at H(2)O(2)/COD weight ratio of 2:1, H(2)O(2)/Fe(2+) molar ratio of 10:1 and 2h of treatment time. The fast pH decrease to acidic values approximately 3 during first min of oxidation for all effluents suggested that pH adjustment was unnecessary. Combination of Fe(III) precipitation and lime coagulation proved feasible to improve considerably COD and residual iron concentration reduction in pharmaceutical effluents. Additionally, considerable BOD(7) reduction and BOD(7)/COD ratio improvement of pharmaceutical wastewater samples was achieved by combined treatment. The application of Fenton-like oxidation with subsequent iron (III)/lime coagulation did not only enhance the quality of pharmaceutical effluents with different chemical characteristics and help to meet the requirements for wastewater discharged to sewage, but also improve the biodegradability of pharmaceutical effluents. PMID:17897701

  4. [Pharmaceutical prescription in primary care. SESPAS report 2012].

    PubMed

    Sanfélix-Gimeno, Gabriel; Peiró, Salvador; Meneu, Ricard

    2012-03-01

    In 2010, the Spanish National Health Service (NHS) paid for 958 million prescriptions. Given the massive population exposure to medication, the risks associated with drug consumption are highly significant from the perspective of public health. Areas requiring improvement in primary care prescription include overtreatment of patients in low risk situations, undertreatment of those in whom medication is indicated, poor patient information, polymedication, self-medication and the appreciable percentage of preventable adverse effects. Surprisingly, most of the pharmaceutical strategies in the NHS have not aimed to address these problems but have instead concentrated on reducing pharmaceutical expenditure, which is not a problem of pharmaceutical expenditure per se but is rather a consequence of "the problems" of prescription (and of the regulation and management of pharmaceutical services). Some key elements to improve this situation include more integrated healthcare, the development of electronic medical records systems, overall strategies to improve safety, and reducing the role of the pharmaceutical industry. Macro strategies include creating an agency able to objectively assess the additional value provided by a new drug and its additional cost, price fixing in line with cost-effectiveness, and exclusion of drugs with little or no added value from coverage, etc. Managing prescription involves the development of longitudinal patient care programs that incorporate clinical actions from different professionals, including whom to treat, how much to treat and how to treat. PMID:22138282

  5. Chitosan/poly (vinyl pyrollidone) coatings improve the antibacterial properties of poly(ethylene terephthalate)

    NASA Astrophysics Data System (ADS)

    Wang, Bai-liang; Wang, Jin-lei; Li, Dan-dan; Ren, Ke-feng; Ji, Jian

    2012-08-01

    Chitosan/poly (vinyl pyrollidone) (CHI/PVP) coatings were prepared to improve the antibacterial properties of poly (ethylene terephthalate) (PET) by a simple dip-coating method. The binding capability of CHI/PVP coatings was enhanced by successively pretreatment of PET by polyetherimide and polyacrylic acid and crosslinking. Measurements of water contact angle and atomic force microscope revealed that the coatings created a highly hydrophilic surface with low roughness. Adherences of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) on PET with CHI/PVP coating were significantly reduced. Bactericidal activity of CHI/PVP coatings was good against E. coli and S. aureus and the adding of PVP obviously increased its antiadhesion property. In vitro cytotoxicity tests, cell morphology and activity evaluation of human umbilical vein endothelial cells showed that CHI/PVP coatings had good biocompatibility.

  6. Improving the O/W emusifying properties of rapeseed lecithin ethanol insoluble fraction by acetylation.

    PubMed

    Sosada, Marian; Pasker, Beata; Bogocz, Marzena

    2003-01-01

    The effect of acetylation of rapeseed lecithin ethanol insoluble fraction (LEIF) containing 25% phosphatidylethanolamine (PE) on the O/W emulsifying properties was reported. In the study, acetic anhydride (50-150 mmol/100 g) and pyridine (0-30 mmole/100 g) were used. The PE conversion to N-acetyl-PE in LEIF determined by the HPLC method was varied from 18.2 to 84.7% and depended essentially on the acetylating agent amount and pyridine quantity used in acetylation. Emulsions of the O/W systems containing lecithin emulsifiers with different PE conversion degree were prepared and evaluated for its stability. It was found that the acetylation of LEIF improves its emulsifying properties and in the formation of emulsions containing soya oil, provided a decrease in oil droplet size and polydispersity index.

  7. Development of process technologies for improvement of electroless nickel coatings properties

    NASA Astrophysics Data System (ADS)

    Barba-Pingarrón, A.; Bolarín-Miró, A.; Sánchez – de Jesús, F.; Vargas-Mendoza, L.; Trujillo-Barragán, M.; Molera-Sola, P.; Hernandez-Gallegos, M. A.; Valdez-Navarro, R.

    2013-06-01

    This paper describes research and technology developments that enable to improve nickel electroless coating properties. This work deals with: (a) different methods in order to achieve Ni-P-Mo coatings. (b) Other development is related with coatings with addition of hard particles such as SiC, WC or Al2O3,(c) Electroless nickel deposits on PBT and austempered ductile iron (ADI). (d) In addition, nickel coatings were deposited on powder metallic pieces and finally, electroless nickel coatings, in conjunction with layers from thermal spray process were formed. Characterization of all coatings by means of optical microscopy, scanning electron microscopy, micro-hardness, wear and corrosion tests were carried out. Results indicate positive increment in both mechanical and electrochemical properties which enhance field applications in Mexican industry.

  8. Method of manipulating the chemical properties of water to improve the effectiveness of a desired process

    DOEpatents

    Hawthorne, Steven B.; Miller, David J.; Lagadec, Arnaud Jean-Marie; Hammond, Peter James; Clifford, Anthony Alan

    2002-01-01

    The method of the present invention is adapted to manipulate the chemical properties of water in order to improve the effectiveness of a desired process. The method involves heating the water in the vessel to subcritical temperatures between 100.degree. to 374.degree. C. while maintaining sufficient pressure to the water to maintain the water in the liquid state. Various physiochemical properties of the water can be manipulated including polarity, solute solubility, surface tension, viscosity, and the disassociation constant. The method of the present invention has various uses including extracting organics from solids and semisolids such as soil, selectively extracting desired organics from liquids, selectively separating organics using sorbent phases, enhancing reactions by controlling the disassociation constant of water, cleaning waste water, removing organics from water using activated carbon or other suitable sorbents, and degrading various compounds.

  9. High-Intensity Ultrasound to Improve Physical and Functional Properties of Lipids.

    PubMed

    Wagh, Ashwini; Birkin, Peter; Martini, Silvana

    2016-01-01

    High-intensity ultrasound (HIU) has been used in recent years to change the crystallization behavior of edible lipids. This technique can be used in combination with other processing technologies to tailor lipids' functional properties and broaden their application for various food products. In general, sonication induces crystallization, increases crystallization rate, and generates a harder and more elastic crystalline network characterized by smaller crystals with a sharper melting profile. An important application of HIU is to improve the hardness and elasticity of shortenings that have a low content of saturated fatty acids and are free of trans-fats. This review summarizes recent research that used HIU to change the physical and functional properties of edible lipids and focuses on the importance of controlling processing variables such as sonication power level and duration and crystallization temperature.

  10. Chemically Derived Dense Alumina-Zirconia Composites for Improved Mechanical and Wear Erosion Properties

    NASA Technical Reports Server (NTRS)

    1998-01-01

    As a result of this funded project high purity Zirconia-Toughened Alumina (ZTA) ceramic powders with and without yttria were produced using metal alkoxide precursors. ZTA ceramic powders with varying volume percents of zirconia were prepared (7, 15, and 22%). Aluminum tri-sec butoxide, zirconium propoxide, and yttrium isopropoxide were the reagents used. Synthesis conditions were varied to control the hydrolysis and the aging conditions for the sol to gel transition. FTIR analysis and rheological characterization were used to follow the structural evolution during the sol to gel transition. The greater extent of hydrolysis and the build-up of structure measured from viscoelastic properties were consistent. Heat treatment was conducted to produce submicron grain fully crystalline ZTA ceramic powders. This improved materials should have enhanced properties such strength, toughness, and wear resistance for advanced structural applications, for example engine components in high technology aerospace applications.

  11. Reinforcement of polyetheretherketone polymer with titanium for improved mechanical properties and in vitro biocompatibility.

    PubMed

    Jung, Hyun-Do; Park, Hui-Sun; Kang, Min-Ho; Li, Yuanlong; Kim, Hyoun-Ee; Koh, Young-Hag; Estrin, Yuri

    2016-01-01

    Blends of ductile Ti metal with polyetheretherketone (PEEK) polymer were studied with regard to their mechanical properties and in vitro biocompatibility. PEEK/Ti composites with various Ti contents, ranging from 0 vol % to 60 vol %, were produced by compression molding at 370°C. In all composites produced, regardless of the initial Ti content, Ti particles were well distributed in the PEEK matrix. Addition of Ti led to a significant increase in mechanical properties of PEEK. Specifically, an increase in Ti content enhanced compressive strength and stiffness, while preserving ductile fracture behavior. In addition, the use of Ti for reinforcement of PEEK provided the composites with improved in vitro biocompatibility in terms of the attachment, proliferation, and differentiation of MC3T3-E1 cells.

  12. Electrospun PS/PAN fibers with improved mechanical property for removal of oil from water.

    PubMed

    Li, Peng; Qiao, Ying; Zhao, Lili; Yao, Dahu; Sun, Haixiang; Hou, Yingfei; Li, Shuo; Li, Qi

    2015-04-15

    A mechanically robust and high-capacity oil sorbent is prepared by electrospinning a blend of polystyrene (PS) and polyacrylonitrile (PAN). The morphology, oil sorption capacity and mechanical property of the fibers formed in different compositions are investigated in detail. It is shown that the oil sorption capacity is a result of both the chemical composition and the specific surface area which related to diameter size. The addition of PAN as a component in fibrous sorbents can significantly improve the mechanical properties of PS fibers. Moreover, the oil sorption capacity increases with decreasing fiber diameter. The results also show that the maximum sorption capacities of the PS/PAN sorbent for pump oil, peanut oil, diesel, and gasoline were 194.85, 131.70, 66.75, and 43.38 g g(-1), respectively. Additionally, the sorbent exhibits quick oil sorption speed as well as high buoyancy, which make it a promising candidate for use as an oil spill cleanup sorbent.

  13. Improved Relationships for the Thermodynamic Properties of Carbon Phases at Detonation Conditions

    NASA Astrophysics Data System (ADS)

    Stiel, Leonard; Baker, Ernest; Murphy, Daniel

    2013-06-01

    In order to improve the procedures utilized in the Jaguar thermochemical program for carbon, volumetric and heat capacity relationships have been developed for graphite, diamond, and liquid carbon forms. Available experimental thermodynamic property and Hugoniot data have been analyzed to establish optimum equations of state for the carbon phases. The appropriate carbon form or multiple forms at equilibrium results from the minimization of the Gibbs free energy of the system. The resulting relationships are utilized to examine the phase behavior of carbon at elevated temperatures and pressures. The behavior of metastable carbon states is optimized by analyses of Hugoniot data for hydrocarbons, and C-J and cylinder velocities for a database of CHNO explosives. The accuracy of the resulting relationships is demonstrated by comparisons for several properties, including the Hugoniot behavior of oxygen-deficient explosives at overdriven conditions.

  14. Improving global access to new vaccines: intellectual property, technology transfer, and regulatory pathways.

    PubMed

    Crager, Sara Eve

    2014-11-01

    The 2012 World Health Assembly Global Vaccine Action Plan called for global access to new vaccines within 5 years of licensure. Current approaches have proven insufficient to achieve sustainable vaccine pricing within such a timeline. Paralleling the successful strategy of generic competition to bring down drug prices, a clear consensus is emerging that market entry of multiple suppliers is a critical factor in expeditiously bringing down prices of new vaccines. In this context, key target objectives for improving access to new vaccines include overcoming intellectual property obstacles, streamlining regulatory pathways for biosimilar vaccines, and reducing market entry timelines for developing-country vaccine manufacturers by transfer of technology and know-how. I propose an intellectual property, technology, and know-how bank as a new approach to facilitate widespread access to new vaccines in low- and middle-income countries by efficient transfer of patented vaccine technologies to multiple developing-country vaccine manufacturers.

  15. [Improving global access to new vaccines: intellectual property, technology transfer, and regulatory pathways].

    PubMed

    Crager, Sara Eve

    2015-01-01

    The 2012 World Health Assembly Global Vaccine Action Plan called for global access to new vaccines within 5 years of licensure. Current approaches have proven insufficient to achieve sustainable vaccine pricing within such a timeline. Paralleling the successful strategy of generic competition to bring down drug prices, a clear consensus is emerging that market entry of multiple suppliers is a critical factor in expeditiously bringing down prices of new vaccines. In this context, key target objectives for improving access to new vaccines include overcoming intellectual property obstacles, streamlining regulatory pathways for biosimilar vaccines, and reducing market entry timelines for developing-country vaccine manufacturers by transfer of technology and know-how. I propose an intellectual property, technology, and know-how bank as a new approach to facilitate widespread access to new vaccines in low- and middle-income countries by efficient transfer of patented vaccine technologies to multiple developing-country vaccine manufacturers.

  16. Application of bioethanol derived lignin for improving physico-mechanical properties of thermoset biocomposites.

    PubMed

    Bajwa, Dilpreet S; Wang, Xinnan; Sitz, Evan; Loll, Tyler; Bhattacharjee, Sujal

    2016-08-01

    Lignin is the most abundant of renewable polymers next to cellulose with a global annual production of 70million tons, largely produced from pulping and second generation biofuel industries. Low value of industrial lignin makes it an attractive biomaterial for wide range of applications. The study investigated the application of wheat straw and corn stover based lignin derived from ethanol production for use in thermoset biocomposites. The biocomposite matrix constituted a two component low viscosity Araldite(®)LY 8601/Aradur(®) 8602 epoxy resin system and the lignin content varied from 0 to 25% by weight fraction. The analysis of the physical and mechanical properties of the biocomposites show bioethanol derived lignin can improve selective properties such as impact strength, and thermal stability without compromising the modulus and strength attributes. PMID:27131732

  17. Improvement of colour strength and colourfastness properties of gamma irradiated cotton using reactive black-5

    NASA Astrophysics Data System (ADS)

    Ahmad Bhatti, Ijaz; Adeel, Shahid; Nadeem, Raziya; Asghar, Toheed

    2012-03-01

    The dyeing behaviour of gamma irradiated cotton fabric using Reactive Black-5 dye powder has been investigated. The mercerized, bleached and plain weaved cotton fabric was irradiated to different absorbed doses of 100, 200, 300, 400, 500 and 600 Gy using Co-60 gamma irradiator. Dyeing was performed using irradiated and un-irradiated cotton with dye solutions. The dyeing parameters such as temperature of dyeing, time of dyeing and pH of dyeing solutions were optimised. The colour strength values of dyed fabrics were evaluated by comparing irradiated and un-irradiated cotton in CIE Lab system using Spectra flash SF650. Methods suggested by International Standard Organisation (ISO) were employed to study the effect of gamma irradiation on the colourfastness properties of dyed fabric. It is found that gamma irradiated cotton dyed with Reactive Black-5 has not only improved the colour strength but also enhanced the rating of fastness properties.

  18. Improvement of polyvinyl alcohol properties by adding nanocrystalline cellulose isolated from banana pseudostems.

    PubMed

    Pereira, André Luís S; do Nascimento, Diego M; Souza Filho, Men de Sá M; Morais, João Paulo S; Vasconcelos, Niedja F; Feitosa, Judith P A; Brígida, Ana Iraidy S; Rosa, Morsyleide de F

    2014-11-01

    Cellulose nanocrystals (CNCs) isolated from banana pseudostems fibers (BPF) of the Pacovan variety were used as fillers in a polyvinyl alcohol (PVOH) matrix to yield a nanocomposite. The fibers from the external fractions of the BPF were alkaline bleached and hydrolyzed under acidic conditions (H2SO4 62% w/w, 70 min, 45 °C) to obtain CNCs with a length (L) of 135.0 ± 12.0 nm and a diameter (D) of 7.2 ± 1.9 nm to yield an aspect ratio (L/D) of 21.2. The CNCs were applied to PVOH films at different concentrations (0%, 1%, 3%, and 5% w/w, dry basis). With higher concentrations of CNCs, the water-vapor barrier of the films increased, while the optical properties changed very little. Increasing the concentration of the CNCs up to 3% significantly improved the mechanical properties of the nanocomposite.

  19. Improving Global Access to New Vaccines: Intellectual Property, Technology Transfer, and Regulatory Pathways

    PubMed Central

    2014-01-01

    The 2012 World Health Assembly Global Vaccine Action Plan called for global access to new vaccines within 5 years of licensure. Current approaches have proven insufficient to achieve sustainable vaccine pricing within such a timeline. Paralleling the successful strategy of generic competition to bring down drug prices, a clear consensus is emerging that market entry of multiple suppliers is a critical factor in expeditiously bringing down prices of new vaccines. In this context, key target objectives for improving access to new vaccines include overcoming intellectual property obstacles, streamlining regulatory pathways for biosimilar vaccines, and reducing market entry timelines for developing-country vaccine manufacturers by transfer of technology and know-how. I propose an intellectual property, technology, and know-how bank as a new approach to facilitate widespread access to new vaccines in low- and middle-income countries by efficient transfer of patented vaccine technologies to multiple developing-country vaccine manufacturers. PMID:25211753

  20. Improved mechanical and electrical properties in electrospun polyimide/multiwalled carbon nanotubes nanofibrous composites

    SciTech Connect

    Zha, Jun-Wei; Sun, Fang; Wang, Si-Jiao; Wang, Dongrui; Lin, Xiang; Dang, Zhi-Min; Chen, George

    2014-10-07

    Highly aligned polyimide (PI) and PI/multi-walled carbon nanotubes (PI/MWCNTs) nanofibrous composites by incorporating poly(ethylene oxide) as the dispersing medium were fabricated using electrospinning technique. The morphology, mechanical, and electrical properties of the electrospun nanofibrous composites were investigated. Scanning electron microscope showed that the functionalized MWCNTs (f-MWCNTs) were well dispersed and oriented along the nanofiber axis. Analysis of electrical properties indicated a remarkable improvement on the alternating current conductivity by introduction of the aligned f-MWCNTs. Besides, with addition of 3 vol. % f-MWCNTs, the obvious enhancement of tensile modulus and strength was achieved. Thus, the electrospun PI/MWCNTs nanofibrous composites have great potential applications in multifunctional engineering materials.

  1. Improving global access to new vaccines: intellectual property, technology transfer, and regulatory pathways.

    PubMed

    Crager, Sara Eve

    2014-11-01

    The 2012 World Health Assembly Global Vaccine Action Plan called for global access to new vaccines within 5 years of licensure. Current approaches have proven insufficient to achieve sustainable vaccine pricing within such a timeline. Paralleling the successful strategy of generic competition to bring down drug prices, a clear consensus is emerging that market entry of multiple suppliers is a critical factor in expeditiously bringing down prices of new vaccines. In this context, key target objectives for improving access to new vaccines include overcoming intellectual property obstacles, streamlining regulatory pathways for biosimilar vaccines, and reducing market entry timelines for developing-country vaccine manufacturers by transfer of technology and know-how. I propose an intellectual property, technology, and know-how bank as a new approach to facilitate widespread access to new vaccines in low- and middle-income countries by efficient transfer of patented vaccine technologies to multiple developing-country vaccine manufacturers. PMID:25211753

  2. High-Intensity Ultrasound to Improve Physical and Functional Properties of Lipids.

    PubMed

    Wagh, Ashwini; Birkin, Peter; Martini, Silvana

    2016-01-01

    High-intensity ultrasound (HIU) has been used in recent years to change the crystallization behavior of edible lipids. This technique can be used in combination with other processing technologies to tailor lipids' functional properties and broaden their application for various food products. In general, sonication induces crystallization, increases crystallization rate, and generates a harder and more elastic crystalline network characterized by smaller crystals with a sharper melting profile. An important application of HIU is to improve the hardness and elasticity of shortenings that have a low content of saturated fatty acids and are free of trans-fats. This review summarizes recent research that used HIU to change the physical and functional properties of edible lipids and focuses on the importance of controlling processing variables such as sonication power level and duration and crystallization temperature. PMID:26735795

  3. UV resonance Raman sensing of pharmaceutical drugs in hollow fibers

    NASA Astrophysics Data System (ADS)

    Yan, D.; Popp, J.; Frosch, T.

    2014-05-01

    We report about the experimental combination of UV resonance Raman sensing (UV-RRS) and fiber enhanced Raman sensing (FERS) on pharmaceuticals. The results show that the chemical sensitivity is highly improved and at the same time the sample volume is reduced compared to conventional measurements. A hundreds-fold improvement of the limit of detection (LOD) has been achieved with the combination of resonance Raman enhancement and fiber enhancement. The enhanced Raman signal has a reliable linear relationship with the concentration of the analyte, and therefore shows great potential for quantitative analysis of pharmaceuticals.

  4. Inhomogeneous thermoelectric materials: improving overall zT by localized property variations

    NASA Astrophysics Data System (ADS)

    Prasad, Narasimha; Nemir, David; Beck, Jan; Maddux, Jay; Taylor, Patrick

    2015-05-01

    The search for improved thermoelectric materials is driven in part by the desire to convert otherwise wasted lowtemperature heat into useful electricity. In this work, we demonstrate a new path towards materials having higher overall zT, and consequently improved capacity to obtain more electrical power from a given content of heat. We produced alloys of (Bi,Sb)2Te3 using a special gas atomization process that is capable of producing source powder material having nanometer-scale grain size. When impulse-compacted by shockwave consolidation, the obtained dense solid will retain its nanostructure because insufficient time and temperature are available for the kinetics of any appreciable grain growth to proceed. However, if there is initial non-uniformity in the properties of the source powder, or if there is stress non-symmetries during shockwave consolidation, then the obtained consolidated material may have locally inhomogeneous properties distributed throughout the material. Thermoelectric property measurements from selected regions within the consolidated sample indicate a wide distribution of properties. For example, the thermal conductivity at room temperature ranged from as low as 1.30 Watts/m-K in one region to higher than 3.00 Watts/m-K in a neighboring region. The electrical resistivity showed similar variation from as low as 0.5 mΩ-cm to as high as 1.5 mΩ-cm. Individually, those regions exhibited thermoelectric material figure-of-merit, zT values ranging between 0.3 and 0.4. However, when combined into a dense nanocomposite, the overall ensemble zT approaches 0.7 which is nearly a factor of 2 higher.

  5. Furfural and its biochar improve the general properties of a saline soil

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Xu, G.; Shao, H. B.

    2014-07-01

    Organic materials (e.g., furfural residue) are generally believed to improve the physical and chemical properties of saline soils with low fertility. Recently, biochar has been received more attention as a possible measure to improve the carbon balance and improve soil quality in some degraded soils. However, little is known about their different amelioration of a sandy saline soil. In this study, 56 d incubation experiment was conducted to evaluate the influence of furfural and its biochar on the properties of saline soil. The results showed that both furfural and biochar greatly reduced pH, increased soil organic carbon (SOC) content and cation exchange capacity (CEC), and enhanced the available phosphorus (P) in the soil. Furfural is more efficient than biochar in reducing pH: 5% furfural lowered the soil pH by 0.5-0.8 (soil pH: 8.3-8.6), while 5% biochar decreased by 0.25-0.4 due to the loss of acidity in pyrolysis process. With respect to available P, furfural addition at a rate of 5% increased available P content by 4-6 times in comparison to 2-5 times with biochar application. In reducing soil exchangeable sodium percentage (ESP), biochar is slightly superior to furfural because soil ESP reduced by 51% and 43% with 5% furfural and 5% biochar at the end of incubation. In addition, no significant differences were observed between furfural and biochar about their capacity to retain N, P in leaching solution and to increase CEC in soil. These facts may be caused by the relatively short incubation time. In general, furfural and biochar exhibited a different effect depending on the property: furfural was more effective in decreasing pH and increasing available P, whereas biochar played a more important role in increasing SOC and reducing ESP of saline soil.

  6. Improving Coastal Ocean Color Validation Capabilities through Application of Inherent Optical Properties (IOPs)

    NASA Technical Reports Server (NTRS)

    Mannino, Antonio

    2008-01-01

    Understanding how the different components of seawater alter the path of incident sunlight through scattering and absorption is essential to using remotely sensed ocean color observations effectively. This is particularly apropos in coastal waters where the different optically significant components (phytoplankton, detrital material, inorganic minerals, etc.) vary widely in concentration, often independently from one another. Inherent Optical Properties (IOPs) form the link between these biogeochemical constituents and the Apparent Optical Properties (AOPs). understanding this interrelationship is at the heart of successfully carrying out inversions of satellite-measured radiance to biogeochemical properties. While sufficient covariation of seawater constituents in case I waters typically allows empirical algorithms connecting AOPs and biogeochemical parameters to behave well, these empirical algorithms normally do not hold for case I1 regimes (Carder et al. 2003). Validation in the context of ocean color remote sensing refers to in-situ measurements used to verify or characterize algorithm products or any assumption used as input to an algorithm. In this project, validation capabilities are considered those measurement capabilities, techniques, methods, models, etc. that allow effective validation. Enhancing current validation capabilities by incorporating state-of-the-art IOP measurements and optical models is the purpose of this work. Involved in this pursuit is improving core IOP measurement capabilities (spectral, angular, spatio-temporal resolutions), improving our understanding of the behavior of analytical AOP-IOP approximations in complex coastal waters, and improving the spatial and temporal resolution of biogeochemical data for validation by applying biogeochemical-IOP inversion models so that these parameters can be computed from real-time IOP sensors with high sampling rates. Research cruises supported by this project provides for collection and

  7. Fabrication of flexible magnetic papers based on bacterial cellulose and barium hexaferrite with improved mechanical properties

    NASA Astrophysics Data System (ADS)

    Lim, Guh-Hwan; Lee, Jooyoung; Kwon, Nayoung; Bok, Shingyu; Sim, Hwansu; Moon, Kyoung-Seok; Lee, Sang-Eui; Lim, Byungkwon

    2016-09-01

    We report on a simple approach to fabricate mechanically robust magnetic cellulose papers containing M-type barium hexaferrite (BaFe12O19) nanoplates. BaFe12O19 nanoplates were synthesized by a hydrothermal method and then chemically functionalized by using a silane coupling agent. The magnetic cellulose papers prepared with the silane-treated BaFe12O19 nanoplates exhibited improved mechanical properties with tensile strength of 58.5 MPa and Young's modulus of 2.95 GPa.

  8. Improved retrievals of the optical properties of cirrus clouds by a combination of lidar methods.

    PubMed

    Cadet, Bertrand; Giraud, Vincent; Haeffelin, Martial; Keckhut, Philippe; Rechou, Anne; Baldy, Serge

    2005-03-20

    We focus on improvement of the retrieval of optical properties of cirrus clouds by combining two lidar methods. We retrieve the cloud's optical depth by using independently the molecular backscattering profile below and above the cloud [molecular integration (MI) method] and the backscattering profile inside the cloud with an a priori effective lidar ratio [particle integration (PI) method]. When the MI method is reliable, the combined MI-PI method allows us to retrieve the optimal effective lidar ratio. We compare these results with Raman lidar retrievals. We then use the derived optimal effective lidar ratio for retrieval with the PI method for situations in which the MI method cannot be applied.

  9. Improving chiral property of domain-wall fermions by reweighting method

    SciTech Connect

    Ishikawa, T.; Aoki, Y.; Izubuchi, T.

    2009-07-25

    The reweighting method is applied to improve the chiral property of domain-wall fermions. One way to achieve this is to enlarge L{sub s}, the size of fifth dimension, which controls the size of the induced chiral symmetry breaking. While this is a type of reweighting method for shifting the action parameter, it seems non-trivial since this reweighting means change of the five dimensional lattice volume. In this report, we address issues in this direction of reweighting and evaluate its effectiveness.

  10. Improving predictions of root biomechanical properties, is age a better determinant than diameter?

    NASA Astrophysics Data System (ADS)

    Loades, Kenneth; Hallett, Paul; Lynch, Jonathan; Chimungu, Joseph; Bengough, Anthony

    2014-05-01

    Roots mechanically reinforce many soils. Root tensile strength and stiffness is critical for soil stabilisation with plants potentially providing civil engineers a 'green' alternative for soil stabilisation. Relatively little is known on factors influencing root tensile strength. Through a better understanding of these factors the adoption of 'green engineering' techniques by civil engineers will improve. Existing models are limited in their accuracy due to simplistic assumptions to derive root contributions to the resistance of soil to failure. Current models typically use relationships between strength and diameter, however, there are a number of other factors potentially influencing root biomechanical properties. The effects of root age on biomechanical properties have largely been overlooked. Barley (Hordeum vulgare) was grown under differing soil conditions, waterlogged, moderate mechanical impedance and in unimpeded, control, conditions. The root system was excavated and tensile tests performed on root sections along the length of each root axis. Root tensile strength increased with increasing distance along the root axes in control soil from 0.5 MPa to 7.0 MPa at a distance of 800mm from the root tip and from 1.0 Mpa to 8.0 MPa, 500mm from the root tip when under moderate mechanical impedance. Increases in strength were also observed when plants were subjected to waterlogging with tensile strength increasing from 1.0 MPa to 3.0 MPa, 200mm from the root tip. Young's modulus increased from ~10 MPa at the root tip to ~60 MPa 400mm and 800mm from the root tip in mechanically impeded and control treatments respectively. Distance from root tip explained over 47% of the variance in root tensile strength and 34% of root stiffness. Including root diameter in the model led to further improvements in predicting root properties, explaining ~54% of root strength variance and ~49% of root stiffness. Root age has been shown to improve predictions of root tensile strength

  11. Research on the property improvement of PVC using red mud in industrial waste residue

    NASA Astrophysics Data System (ADS)

    Nie, Xiaopeng; Li, Xingang; Shuai, Songxian

    2015-07-01

    Red mud is a red solid power waste that is discharged in the aluminium refinery industry during production. It is a strong alkali and can be categorized as polluting industrial residue. How to make comprehensive use of red mud has become a worldwide issue. In this paper, we put red mud into PVC (polyvinyl chloride polymer), taking advantage of the complicated chemical properties of red mud derived from the Bayer process. The results are compared with silica fume, coal ash and calcium carbonate under the same experimental conditions, which shows that improvement of PVC plastication can be achieved by adding red mud.

  12. Fabrication of flexible magnetic papers based on bacterial cellulose and barium hexaferrite with improved mechanical properties

    NASA Astrophysics Data System (ADS)

    Lim, Guh-Hwan; Lee, Jooyoung; Kwon, Nayoung; Bok, Shingyu; Sim, Hwansu; Moon, Kyoung-Seok; Lee, Sang-Eui; Lim, Byungkwon

    2016-08-01

    We report on a simple approach to fabricate mechanically robust magnetic cellulose papers containing M-type barium hexaferrite (BaFe12O19) nanoplates. BaFe12O19 nanoplates were synthesized by a hydrothermal method and then chemically functionalized by using a silane coupling agent. The magnetic cellulose papers prepared with the silane-treated BaFe12O19 nanoplates exhibited improved mechanical properties with tensile strength of 58.5 MPa and Young's modulus of 2.95 GPa. [Figure not available: see fulltext.

  13. Multifunctional fuel additives derived from aminodiols to improve the low-temperature properties of distillate fuels

    SciTech Connect

    Baillargeon, D.J.; Cardis, A.B.; Heck, D.B.

    1991-03-19

    This patent describes a liquid hydrocarbyl fuel composition comprising a major amount of a combustible liquid hydrocarbon fuel and a minor low-temperature properties improving amount of from about 0.001% to about 10 wt % based on the total weight of the composition of an additive comprising a product of reaction made by reacting comonomers. It comprises: an aminodiol or combination or mixture of aminodiols with a reactive acid/anhydride product alone or in combination with other monomers derived from the reaction of benzophenone tetracarboxylic dianhydride or its acid equivalent.

  14. Influence of surface modified cellulose microfibrils on the improved mechanical properties of poly (lactic acid).

    PubMed

    Johari, Atul P; Kurmvanshi, S K; Mohanty, S; Nayak, S K

    2016-03-01

    Cellulose microfibrils (CMF) were extracted from sisal fiber and characterized. Biocomposites of PLA reinforced with CMF were fabricated employing melt blending technique followed by injection moulding. The biocomposites were subjected to various characterization studies to investigate the effect of CMF within the PLA matrix. Differential scanning calorimetry (DSC) measurements confirmed that the addition of CMF accelerates the crystallization process of PLA matrix. Addition of 5 wt.% of CMF with and without compatibilizers and plasticizers such as maleic anhydride, polyethylene glycol and acetyltributyl citrate in PLA improved the crystallization of PLA up to 100 °C. MA grafting gave moderate effects on both the stiffness and ductility, exhibiting optimum properties. PMID:26708431

  15. Biocomposites of cellulose reinforced starch: improvement of properties by photo-induced crosslinking.

    PubMed

    Kumar, Annamalai Pratheep; Singh, Raj Pal

    2008-12-01

    In the present study, the composite films have been prepared from the aqueous dispersions of starch with microcrystalline cellulose using glycerol as plasticizer and irradiated under ultraviolet (UV) light using sodium benzoate as photo-sensitizer. Photo-crosslinking was characterized by measuring the water absorption under 100% relative humidity, swelling degree and gel fraction in dimethylsulphoxide (DMSO), upon irradiation time. Both, the incorporation of cellulose and photo-irradiation were found to decrease the water absorption, swelling in DMSO and increase the gel fraction. Thermal transitions indicated the anti-plasticization of amylopectin chains at the fiber/matrix interface. With increasing content of cellulose and photo-irradiation time, the tensile modulus and strength were found to improve. It is summarized that the combination of cellulose reinforcement and photo-crosslinking of matrix has improved the physical and mechanical properties.

  16. Improvement of reinforced concrete properties based on modified starch/polybutadiene nanocomposites.

    PubMed

    Saboktakin, Amin; Saboktakin, Mohammad Reza

    2014-09-01

    A novel polymer-modified cement concrete with carboxymethyl starch (CMS) and 1,4-cis polybutadiene (PBD) system by mixing polymer dispersions or redispersible polymer powders with the fresh mixture have been examined. In this paper, the addition of CMS-PBD powders in an aqueous solution is studied. Polymeric molecules are supplied on a molecular scale, improving the approach of the relatively large cement grains by the polymers. The chemical and mechanical properties of CMS-PBD-modified cement concrete have been studied. The additions of very small amounts of CMS-PBD polymeric system results in an improvement of the durability and the adhesion strength of the cementitious materials, which makes them appropriate as repair materials. PMID:25036606

  17. Improvement of mechanical properties by additive assisted laser sintering of PEEK

    SciTech Connect

    Kroh, M. Bonten, C.; Eyerer, P.

    2014-05-15

    The additive assisted laser sintering was recently developed at IKT: A carbon black (CB) additive is used to adjust the polymer's laser absorption behavior with the aim to improve the interconnection of sintered powder layers. In this paper a parameter study, Polyetheretherketone (PEEK) samples were prepared with different contents of carbon black and were laser sintered with varying thermal treatment. The samples were mechanically tested and investigated by optical light and transmission electron microscopy. An influence on the morphology at the border areas of particles and intersections of laser sintered layers was found. Depending on the viscosity of the raw material and CB content, different shapes of lamellae were observed. These (trans-) crystalline or polymorph structures, respectively, influence the thermal and mechanical behavior of the virgin PEEK. Moreover, the thermal treatment during the sintering process caused an improvement of mechanical properties like tensile strength and elongation at break.

  18. Improvement of bleached wheat straw pulp properties by using aspen high-yield pulp.

    PubMed

    Zhang, Hongjie; Li, Jianguo; Hu, Huiren; He, Zhibin; Ni, Yonghao

    2012-09-01

    The bleached wheat straw pulp (BWSP) accounts for about 25% of the virgin fiber supply in the Chinese Pulp and Paper Industry. As a non-wood chemical pulp, BWSP is known to have low bulk, low light scattering coefficient and poor drainage due to its high content of parenchyma cells. In this study, a high-quality aspen high-yield pulp (HYP) was used to improve the BWSP properties at the laboratory scale. The results indicate that adding 5-20% aspen HYP into unrefined or refined BWSP can minimize many of the drawbacks associated with the BWSP: improving its drainage, bulk, light scattering coefficient and opacity. The addition of a small amount (up to 20%) of aspen HYP can also significantly increase the tear index of BWSP with only a slight decrease of the tensile index.

  19. Improvement of reinforced concrete properties based on modified starch/polybutadiene nanocomposites.

    PubMed

    Saboktakin, Amin; Saboktakin, Mohammad Reza

    2014-09-01

    A novel polymer-modified cement concrete with carboxymethyl starch (CMS) and 1,4-cis polybutadiene (PBD) system by mixing polymer dispersions or redispersible polymer powders with the fresh mixture have been examined. In this paper, the addition of CMS-PBD powders in an aqueous solution is studied. Polymeric molecules are supplied on a molecular scale, improving the approach of the relatively large cement grains by the polymers. The chemical and mechanical properties of CMS-PBD-modified cement concrete have been studied. The additions of very small amounts of CMS-PBD polymeric system results in an improvement of the durability and the adhesion strength of the cementitious materials, which makes them appropriate as repair materials.

  20. Improvement of mechanical properties by additive assisted laser sintering of PEEK

    NASA Astrophysics Data System (ADS)

    Kroh, M.; Bonten, C.; Eyerer, P.

    2014-05-01

    The additive assisted laser sintering was recently developed at IKT: A carbon black (CB) additive is used to adjust the polymer's laser absorption behavior with the aim to improve the interconnection of sintered powder layers. In this paper a parameter study, Polyetheretherketone (PEEK) samples were prepared with different contents of carbon black and were laser sintered with varying thermal treatment. The samples were mechanically tested and investigated by optical light and transmission electron microscopy. An influence on the morphology at the border areas of particles and intersections of laser sintered layers was found. Depending on the viscosity of the raw material and CB content, different shapes of lamellae were observed. These (trans-) crystalline or polymorph structures, respectively, influence the thermal and mechanical behavior of the virgin PEEK. Moreover, the thermal treatment during the sintering process caused an improvement of mechanical properties like tensile strength and elongation at break.

  1. An Experimental Investigation towards Improvement of Thermoelectric Properties of Strontium Titanate Ceramics

    NASA Astrophysics Data System (ADS)

    Mehdizadeh Dehkordi, Arash

    The direct energy conversion between heat and electricity based on thermoelectric effects is a topic of long-standing interest in condensed matter materials science. Experimental and theoretical investigations in order to understand the mechanisms involved and to improve the materials properties and conversion efficiency have been ongoing for more than half a century. While significant achievements have been accomplished in improving the properties of conventional heavy element based materials (such as Bi2Te 3 and PbTe) as well as the discovery of new materials systems for the close-to-room temperature and intermediate temperatures, high-temperature applications of thermoelectrics is still limited to one materials system, namely SiGe. Recently, oxides have exhibited great potential to be investigated for high-temperature thermoelectric power generation. The objective of this dissertation is to synthesize and investigate both electronic and thermal transport in strontium titanate (SrTiO3) ceramics in order to experimentally realize its potential and to ultimately investigate the possibility of further improvement of the thermoelectric performance of this perovskite oxide for mid- to high temperature applications. Developing a synthesis strategy and tuning various synthesis parameters to benefit the thermoelectric transport form the foundation of this study. It is worth mentioning that the results of this study has been employed to prepare targets for pulsed-laser deposition (PLD) to study the thermoelectric properties of corresponding thin films and superlattice structures at Dr. Husam Alshareef's group at King Abdullah University of Science and Technology (KAUST), Saudi Arabia. Considering the broad range of functionality of SrTiO3, the findings of this work will surely benefit other fields of research and application of this functional oxide such as photoluminescence, ferroelectricity or mixed-ionic electronic conductivity. This dissertation will ultimately

  2. Improvement of physicomechanical properties of carbamazepine by recrystallization at different pH values.

    PubMed

    Javadzadeh, Yousef; Mohammadi, Ameneh; Khoei, Nazaninossadat Seyed; Nokhodchi, Ali

    2009-06-01

    The morphology of crystals has an appreciable impact role on the physicochemical properties of drugs. Drug properties such as flowability, dissolution, hardness and bioavailability may be affected by crystallinity behaviours of drugs. The objective of this study was to achieve an improved physicomechanical property of carbamazepine powder through recrystallization from aqueous solutions at different pH values. For this purpose, carbamazapine was recrystallized from aqueous solutions at different pH values (1, 7, 11). The morphology of crystals was investigated using scanning electron microscopy; X-ray powder diffraction (XRPD) was used to identify polymorphism; thermodynamic properties were analyzed using differential scanning calorimetery (DSC). Dissolution rate was determined using USP dissolution apparatus. Mechanical behavior of recrystallized carbamazepine powders was investigated by making tablets under different compaction pressure and measuring their hardness. SEM studies showed that the carbamazepine crystallization in different media affected the morphology and size of carbamazepine crystals. The shape of carbamazepine crystals changed from flaky or thin plate-like to needle shape. XRPD and DSC results ruled out any crystallinity changes occurring due to the temperature during recrystallization procedure or pH of crystallization media. The crushing strength of tablets indicated that all of the recrystallized carbamazepine samples had better compactiblity than the original carbamazepine powder. In vitro dissolution studies of carbamazepine samples showed a higher dissolution rate for carbamazepine crystals obtained from media with pH 11 and 1. Carbamazepine particles recrystallized from aqueous solutions of different pH values (all media) appeared to have superior mechanical properties to those of the original carbamazepine sample.

  3. Virtual pharmaceutical companies: collaborating flexibly in pharmaceutical development.

    PubMed

    Forster, Simon P; Stegmaier, Julia; Spycher, Rene; Seeger, Stefan

    2014-03-01

    Research and development (R&D) collaborations represent one approach chosen by the pharmaceutical industry to tackle current challenges posed by declining internal R&D success rates and fading of the blockbuster model. In recent years, a flexible concept to collaborate in R&D has emerged: virtual pharmaceutical companies (VPCs). These differ from other R&D companies, such as biotech start-ups, collaborating with big pharmaceutical companies, because they solely comprise experienced teams of managers. VPCs have only been described anecdotally in literature. Thus, we present here the characteristics of a VPC and suggest how big pharma can leverage the concept of VPCs by introducing five possible modes of collaboration. We find that one mode, investing, is particularly promising for big pharma. PMID:24291787

  4. Virtual pharmaceutical companies: collaborating flexibly in pharmaceutical development.

    PubMed

    Forster, Simon P; Stegmaier, Julia; Spycher, Rene; Seeger, Stefan

    2014-03-01

    Research and development (R&D) collaborations represent one approach chosen by the pharmaceutical industry to tackle current challenges posed by declining internal R&D success rates and fading of the blockbuster model. In recent years, a flexible concept to collaborate in R&D has emerged: virtual pharmaceutical companies (VPCs). These differ from other R&D companies, such as biotech start-ups, collaborating with big pharmaceutical companies, because they solely comprise experienced teams of managers. VPCs have only been described anecdotally in literature. Thus, we present here the characteristics of a VPC and suggest how big pharma can leverage the concept of VPCs by introducing five possible modes of collaboration. We find that one mode, investing, is particularly promising for big pharma.

  5. Recent developments in the experimental investigations of relaxations in pharmaceuticals by dielectric techniques at ambient and elevated pressure.

    PubMed

    Grzybowska, Katarzyna; Capaccioli, Simone; Paluch, Marian

    2016-05-01

    In recent years, there is a growing interest in improving the physicochemical stability of amorphous pharmaceutical solids due to their very promising applications to manufacture medicines characterized by a better water solubility, and consequently by a higher dissolution rate than those of their crystalline counterparts. In this review article, we show that the molecular mobility investigated both in the supercooled liquid and glassy states is the crucial factor required to understand molecular mechanisms that govern the physical stability of amorphous drugs. We demonstrate that pharmaceuticals can be thoroughly examined by means of the broadband dielectric spectroscopy, which is a very useful experimental technique to explore different relaxation processes and crystallization kinetics as well. Such studies conducted in the wide temperature and pressure ranges provide data needed in searching correlations between properties of molecular dynamics and crystallization process, which are aimed at developing effective and efficient methods for stabilizing amorphous drugs. PMID:26705851

  6. Computational methods for improving estimates of motor unit twitch contraction properties.

    PubMed

    Lim, K Y; Thomas, C K; Rymer, W Z

    1995-02-01

    Estimates of mechanical properties of human motor units have usually been made indirectly, using the technique of "spike-triggered averaging" (STA). In this method, a single motor unit action potential is used to synchronize the accumulation of an ensemble average of correlated force transients. However, under most realizable conditions, these transients are recorded during periods of sustained motor unit discharge, in which each motor unit is producing a partially fused tetanus. Therefore, the STA technique extracts the characteristics of the unfused force transient, instead of the desired single motor unit twitch. Although the STA method has been widely used, there is as yet no well-established relation between the force transient in the unfused tetanus, and the twitch contraction properties of the motor unit. To evaluate the accuracy of the STA as a measure of the motor unit mechanical properties, we applied two types of muscle models to the force transients recorded in an unfused tetanus, using data derived from experiments in which the response to a single twitch was also recorded. Our objective was to see whether accurate predictions of single motor unit mechanical characteristics are possible, working backward from the STA. The models chosen for this task were a linear second order model, and the distribution-moment (DM) model. These model predictions were then compared with the STA response, and with the twitch properties of the individual motor units. We also evaluated the utility of extrapolating the initial slope of the STA backward to improve the accuracy of the mechanical estimates. The results of our simulation suggest that there is no straightforward relation between the characteristics of the unfused tetanus and the mechanical properties of the single twitch. Although our attempts to predict the properties of the single twitch from the STA were only partly successful, the results of the simulations were far more accurate than those derived from the

  7. Improved Protection Properties by Using Nanostructured Ceramic Powders for HVOF Coatings

    NASA Astrophysics Data System (ADS)

    Varis, T.; Knuuttila, J.; Turunen, E.; Leivo, J.; Silvonen, J.; Oksa, M.

    2007-12-01

    The potential of the high-velocity oxy-fuel (HVOF) thermal spray process for reduced porosity in coatings compared to those produced by other ambient thermal spray processes is well known. The ability to produce high-density ceramic coatings offers potential in high-performance applications in the field of wear, corrosion resistance, and dielectric coatings. However, due to operational limit of the HVOF process to effectively melt the ceramic particles, the process—structure relationship must be well optimized. It has been also demonstrated that benefits from HVOF ceramic coatings can be obtained only if particles are melted enough and good lamella adhesion is produced. One strategy to improve melting of ceramic particles in relative low-flame temperatures of HVOF process is to modify particle crystal structure and composition. In this paper the effect of the powder manufacturing method and the composition on deposition efficiency of spray process as well as on the mechanical properties of the HVOF sprayed are studied. Effect of fuel gas, hydrogen vs. propane, was also demonstrated. Studied materials were alumina-, chromia-, and titania-based agglomerated powders. Coating properties such as microstructure, hardness, abrasive wear resistance, and relative fracture toughness were compared to the coating manufactured by using conventional fused and crushed powders. It can be concluded that powder size distribution and microstructure should be optimized to fulfill process requirements very carefully to produce coatings with high deposition efficiency, dense structure, improved fracture toughness, and adhesion.

  8. A numerical investigation on mechanical property improvement of styrene butadine rubber by static straight blade indentation

    NASA Astrophysics Data System (ADS)

    Setiyana, B.; Ismail, R.; Jamari, J.; Schipper, D. J.

    2016-04-01

    Mechanical property improvement of rubber is widely carried out by adding carbon black or silica as a filler in rubber. In general, this improvement aims on the increase of stiffness and abrasion resistance. By means of the static straight blade indentation technique, this paper studies the mechanical properties of Unfilled Styrene Butadiene Rubber (SBR-0) and Filled Styrene Butadiene Rubber that is compounded with carbon black (SBR-25). The numerical method applied was Finite Element Analysis (FEA) in which the rubber was modeled as a hyper-elastic material and indented by a blade indenter with various wedge angles i.e. 30, 45 and 60 degrees. At the same depth of indentation, the results showed that there was an increase in both rubber stiffness and maximum stress if the rubber was compounded. However, it is found that the rubber stiffness showed a regular slight increase, while the maximum stress experienced an irregularly significant increase. Especially for the 30 degree wedge angle, the maximum stress extremely increased at a certain depth of indentation.

  9. Polylactic acid with improved heat deflection temperatures and self-healing properties for durable goods applications.

    PubMed

    Wertz, J T; Mauldin, T C; Boday, D J

    2014-11-12

    A method to recover fracture toughness after failure and increase thermal properties of polylactic acid (PLA) for use within durable goods applications is presented. Microcapsules were incorporated into PLA to form a composite material in which the microcapsules served the dual purpose of (1) releasing self-healing additives to fracture regions and (2) serving as nucleating agents to improve the PLA composite's thermal tolerance. Self-healing was achieved though embedment of dicyclopentadiene-filled microcapsules and Grubbs' first generation ruthenium metathesis catalyst, the former being autonomically released into damage volumes and undergoing polymerization in the presence of the catalyst. This approach led to up to 84% recovery of the polymer composite's initial fracture toughness. Additionally, PLA's degree of crystallinity and heat deflection temperature were improved by ∼ 11% and ∼ 21 °C, respectively, relative to nonfilled virgin PLA, owing to microcapsule-induced nucleation. The self-healing system developed here overcomes many property limitations of PLA that can potentially lead to its incorporation into various durable goods.

  10. Manipulating dispersion and distribution of graphene in PLA through novel interface engineering for improved conductive properties.

    PubMed

    Fu, Yu; Liu, Linshu; Zhang, Jinwen

    2014-08-27

    This study aimed to enhance the conductive properties of PLA nanocomposite by controlling the dispersion and distribution of graphene within the minor phase of the polymer blend. Functionalized graphene (f-GO) was achieved by reacting graphene oxide (GO) with various silanes under the aid of an ionic liquid. Ethylene/n-butyl acrylate/glycidyl methacrylate terpolymer elastomer (EBA-GMA) was introduced as the minor phase to tailor the interface of matrix/graphene through reactive compatibilization. GO particles were predominantly dispersed in PLA in a self-agglomerating pattern, while f-GO was preferentially located in the introduced rubber phase or at the PLA/EBA-GMA interfaces through the formation of the three-dimensional percolated structures, especially for these functionalized graphene with reactive groups. The selective localization of the f-GO also played a crucial role in stabilizing and improving the phase morphology of the PLA blend through reducing the interfacial tension between two phases. The establishment of the percolated network structures in the ternary system was responsible for the improved AC conductivity and better dielectric properties of the resulting nanocomposites. PMID:25014782

  11. Improvement of the Pharmacological Properties of Maize RIP by Cysteine-Specific PEGylation

    PubMed Central

    Au, Ka-Yee; Shi, Wei-Wei; Qian, Shuai; Zuo, Zhong; Shaw, Pang-Chui

    2016-01-01

    To improve the pharmacological properties of maize ribosome-inactivating protein (maize RIP) for targeting HIV-infected cells, the previously engineered TAT-fused active form of maize RIP (MOD) was further engineered for cysteine-directed PEGylation. In this work, two potential antigenic sites, namely Lys-78 and Lys-264, were identified. They were mutated to cysteine residue and conjugated with PEG5k or PEG20k. The resultant PEG derivatives of MOD variants were examined for ribosome-inactivating activity, circulating half-life and immunogenicity. Our results showed that MOD-PEG conjugates had two- to five-fold lower biological activity compared to the wild-type. Mutation of the two sites respectively did not decrease the anti-MOD IgG and IgE level in mice, but the conjugation of PEG did dramatically reduce the antigenicity. Furthermore, pharmacokinetics studies demonstrated that attachment of PEG20k prolonged the plasma half-life by five-fold for MOD-K78C and 17-fold for MOD-K264C, respectively. The site-specific mutation together with PEGylation therefore generated MOD derivatives with improved pharmacological properties. PMID:27763506

  12. Graphene-Alumina Nanocomposites with Improved Mechanical Properties for Biomedical Applications.

    PubMed

    Liu, Jian; Yang, Yang; Hassanin, Hany; Jumbu, Neeraj; Deng, Sunan; Zuo, Qian; Jiang, Kyle

    2016-02-01

    This paper presents a study on graphene platelet (GPL)-reinforced alumina (Al2O3) ceramic composites and the relationships between the loading of GPL and both mechanical properties and in vitro biocompatibility. Al2O3 powders with different GPL contents were prepared and sintered using a gas protected pressure-less furnace. The examination of the results shows the density of the composites varying from 99.2% to 95.6% with the loading of GPL from 0.75 to 1.48 vol %. Raman studies show that moderate agglomerations of GPLs occur during the ball milling process and graphitic defects were produced during the high temperature processing. Mechanical properties of the Al2O3 matrix are significantly improved by adding GPLs. A maximum increase of approximately 60% in flexural strength and 70% in fracture toughness are achieved by introducing 0.75 vol % GPLs. In the biocompatibility tests, it was found that cells directly seeding on top of GPL/Al2O3 samples showed better initial attachment (3 h after seeding) and viability (3 days after incubation) than the monolithic Al2O3, indicating that the GPL/Al2O3 composites have comparable or more favorable biocompatibility. The excellent mechanical and biomedical properties of the GPL/Al2O3 composites may enable them to be applied to a wide range of engineering and biomedical applications.

  13. Microstructural modification of pure Mg for improving mechanical and biocorrosion properties.

    PubMed

    Ahmadkhaniha, D; Järvenpää, A; Jaskari, M; Sohi, M Heydarzadeh; Zarei-Hanzaki, A; Fedel, M; Deflorian, F; Karjalainen, L P

    2016-08-01

    In this study, the effect of microstructural modification on mechanical properties and biocorrosion resistance of pure Mg was investigated for tailoring a load-bearing orthopedic biodegradable implant material. This was performed utilizing the friction stir processing (FSP) in 1-3 passes to refine the grain size. Microstructure was examined in an optical microscope and scanning electron microscope with an electron backscatter diffraction unit. X-ray diffraction method was used to identify the texture. Mechanical properties were measured by microhardness and tensile testing. Electrochemical impedance spectroscopy was applied to evaluate corrosion behavior. The results indicate that even applying a single pass of FSP refined the grain size significantly. Increasing the number of FSP passes further refined the structure, increased the mechanical strength and intensified the dominating basal texture. The best combination of mechanical properties and corrosion resistance were achieved after three FSP passes. In this case, the yield strength was about six times higher than that of the as-cast Mg and the corrosion resistance was also improved compared to that in the as-cast condition. PMID:27108346

  14. New Soft Magnetic Composites for electromagnetic applications with improved mechanical properties

    NASA Astrophysics Data System (ADS)

    Ferraris, Luca; Pošković, Emir; Franchini, Fausto

    2016-05-01

    The chance to move from 2D to 3D approach in the design of the electrical machines is made possible by the availability of Soft Magnetic Composites (SMC), iron based powders, insulated and pressed to realize shapes otherwise impossible with the traditional lamination sheets technology. Some commercial products are available on the market as "ready to press" powders, which presents good magnetic and energetic properties but are sometimes weak under the mechanical point of view; other products aim at improving this aspect but with considerable process complications and relative cost. The experience of the Authors in the realization of bonded magnets with the adoption of selected organic resins has been partly transferred in the research field of the SMC in order to investigate the possibility to obtain good mechanical properties maintaining the magnetic characteristics of the Insulated Iron Powder Compounds (I.I.P.C.) taken as reference. The paper presents the activity that has been carried out in the realization of SMC mixing iron powders and phenolic resin, in different weight percentages and mold pressures. The obtained results are considered satisfactory under the point of view of the compromise between magnetic and mechanical properties, considering also that the required productive process is simpler. The comparison of the obtained results with those related to commercial products encourages to carry on the research, also because of the reduced cost of the proposed SMC at parity (or better) performance.

  15. Microstructural modification of pure Mg for improving mechanical and biocorrosion properties.

    PubMed

    Ahmadkhaniha, D; Järvenpää, A; Jaskari, M; Sohi, M Heydarzadeh; Zarei-Hanzaki, A; Fedel, M; Deflorian, F; Karjalainen, L P

    2016-08-01

    In this study, the effect of microstructural modification on mechanical properties and biocorrosion resistance of pure Mg was investigated for tailoring a load-bearing orthopedic biodegradable implant material. This was performed utilizing the friction stir processing (FSP) in 1-3 passes to refine the grain size. Microstructure was examined in an optical microscope and scanning electron microscope with an electron backscatter diffraction unit. X-ray diffraction method was used to identify the texture. Mechanical properties were measured by microhardness and tensile testing. Electrochemical impedance spectroscopy was applied to evaluate corrosion behavior. The results indicate that even applying a single pass of FSP refined the grain size significantly. Increasing the number of FSP passes further refined the structure, increased the mechanical strength and intensified the dominating basal texture. The best combination of mechanical properties and corrosion resistance were achieved after three FSP passes. In this case, the yield strength was about six times higher than that of the as-cast Mg and the corrosion resistance was also improved compared to that in the as-cast condition.

  16. Possibility of tree selection and breeding for genetic improvement of wood properties of Gmelina arborea

    SciTech Connect

    Akachuku, A.E.

    1984-06-01

    Wood samples of Gmelina arborea were collected from Nigerian plantations. The wood density was measured with an X-ray densitometer. Fiber length was measured with a modified map measurer. Fiber proportion was determined with a modification of Ladell's (1959) randomized dot technique. Considerable between-tree differences were observed in wood density, fiber length, fiber proportion, and sizes of trees of the same age, planted at the same spacing within the same environment. The magnitude of within-tree variations in these wood properties was different in trees within the same plot. Some individual trees combined comparatively high density, fiber length, and fiber proportion with fast growth rate and uniform wood. There was sufficient phenotypic variation to encourage genetic improvement of the wood properties and growth rate by selecting and breeding trees with higher values of these traits. Tree selection should be based on a preliminary screening for tree form and volume growth followed by a second selection for the desired wood properties.

  17. Inkjet printed highly porous TiO2 films for improved electrical properties of photoanode.

    PubMed

    Bernacka-Wojcik, I; Wojcik, P J; Aguas, H; Fortunato, E; Martins, R

    2016-03-01

    The aim of presented work is to show the improvements obtained in the properties of TiO2 films for dye sensitized solar cells fabricated by inkjet printing using an innovative methodology. We describe the development and properties of TiO2-based inks used in a lab-scale printer, testing various commercial TiO2 pastes. The porosity of the deposited inkjet printed TiO2 films is much higher than using the conventional "doctor blade" deposition technique, as the ink solvent evaporates during the droplet fly from the nozzle to the substrate due to its picoliter volume and the applied heating of a printing stage (70°C). Thanks to higher surface area, the dye sensitized solar cells incorporating inkjet printed TiO2 film gave higher efficiencies (ηmax≈3.06%) than the more compact films obtained by the "doctor blade" method (ηmax≈2.56%). Furthermore, electrochemical analysis indicates that for whole tested thickness range, the inkjet printed layers have higher effective electron diffusion length indicating their better transport properties.

  18. Use of Mucor miehei lipase to improve functional properties of yolk-contaminated egg whites.

    PubMed

    Macherey, Laura N; Conforti, Frank D; Eigel, William; O'Keefe, Sean F

    2011-05-01

    Egg yolk contamination of egg whites continues to be a serious problem in the egg industry. The ability of egg whites to form stable and voluminous foams is greatly inhibited by yolk contamination, even at very low levels, between 0.01% and 0.2% w/w yolk in white. Experiments were conducted to determine if Mucor miehei lipase could regenerate the functional properties of yolk-contaminated egg whites. Lipase from M. miehei and colipase from porcine pancreas were added to yolk-contaminated (0.2%, w/w) egg white samples to hydrolyze triglycerides originating from egg yolk. Enzymatic hydrolysis of triacylglycerols was confirmed using thin-layer chromatography. Treatment of yolk-contaminated samples with lipase and colipase yielded significant (P < 0.05) improvements in a number of the functional properties, including the final foam volume, foam capacity, and foaming power. These functional properties showed complete restoration to control levels. However, foam stability and foam drainage levels were not statistically different from yolk-contaminated samples that had not been enzymatically treated. Enzyme-treated yolk-contaminated egg whites were also tested in angel food cakes. Enzyme-treated, yolk-contaminated egg whites performed similarly to non-yolk-contaminated control, and much better than yolk-contaminated sample in angel food cakes. The results show that most negative effects of yolk contamination can be reversed by treatment with Mucor miehei lipase and colipase.

  19. Nano-composite coatings with improved mechanical properties and corrosion resistance by thermal spraying

    NASA Astrophysics Data System (ADS)

    Zhong, X. C.; Liu, Z. W.; Wu, Y. S.; Liu, M. T.; Zeng, D. C.

    2014-06-01

    This paper reports the synthesis and characterization of nanostructured coatings. To improve the mechanical properties and oxidation resistance of the materials, two new types of nanostructured coatings including CoNiCrAlY-MoSi2 and Ni60-TiB2 were designed. The nanocrystalline feedstock powders were prepared by high energy ball milling (HEBM). The particle size, morphology and grain size of the feed stocks were investigated. The preparation, microstructure, mechanical properties, and anti-oxidation behavior of the nanostructured CoNiCrAlY-MoSi2 and Ni60-TiB2 coatings are presented. With a lamellar and compact structure, the optimized nano-composite CoNiCrAlY-MoSi2 coatings is metallurgically bonded with the substrate. It exhibits low porosity, high fracture toughness and excellent thermal shock resistance. The nanostructured Ni60-TiB2 composite coatings also exhibited better mechanical properties and wear-corrosion resistance than those of its conventional counterpart. This work is expected to play an important role in the preparation and application of high performance nanostructured coatings.

  20. Improving the mechanical properties of collagen-based membranes using silk fibroin for corneal tissue engineering.

    PubMed

    Long, Kai; Liu, Yang; Li, Weichang; Wang, Lin; Liu, Sa; Wang, Yingjun; Wang, Zhichong; Ren, Li

    2015-03-01

    Although collagen with outstanding biocompatibility has promising application in corneal tissue engineering, the mechanical properties of collagen-based scaffolds, especially suture retention strength, must be further improved to satisfy the requirements of clinical applications. This article describes a toughness reinforced collagen-based membrane using silk fibroin. The collagen-silk fibroin membranes based on collagen [silk fibroin (w/w) ratios of 100:5, 100:10, and 100:20] were prepared by using silk fibroin and cross-linking by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. These membranes were analyzed by scanning electron microscopy and their optical property, and NaCl and tryptophan diffusivity had been tested. The water content was found to be dependent on the content of silk fibroin, and CS10 membrane (loading 10 wt % of silk fibroin) performed the optimal mechanical properties. Also the suture experiments have proved CS10 has high suture retention strength, which can be sutured in rabbit eyes integrally. Moreover, the composite membrane proved good biocompatibility for the proliferation of human corneal epithelial cells in vitro. Lamellar keratoplasty shows that CS10 membrane promoted complete epithelialization in 35 ± 5 days, and their transparency is restored quickly in the first month. Corneal rejection reaction, neovascularization, and keratoconus are not observed. The composite films show potential for use in the field of corneal tissue engineering.

  1. Hybrid PGS-PCL microfibrous scaffolds with improved mechanical and biological properties.

    PubMed

    Sant, Shilpa; Hwang, Chang Mo; Lee, Sang-Hoon; Khademhosseini, Ali

    2011-04-01

    Poly(glycerol sebacate) (PGS) is a biodegradable elastomer that has generated great interest as a scaffold material due to its desirable mechanical properties. However, the use of PGS in tissue engineering is limited by difficulties in casting micro- and nanofibrous structures, due to high temperatures and vacuum required for its curing and limited solubility of the cured polymer. In this paper, we developed microfibrous scaffolds made from blends of PGS and poly(ε-caprolactone) (PCL) using a standard electrospinning set-up. At a given PGS:PCL ratio, higher voltage resulted in significantly smaller fibre diameters (reduced from ∼4 µm to 2.8 µm; p < 0.05). Further increase in voltage resulted in the fusion of fibres. Similarly, higher PGS concentrations in the polymer blend resulted in significantly increased fibre diameter (p < 0.01). We further compared the mechanical properties of electrospun PGS:PCL scaffolds with those made from PCL. Scaffolds with higher PGS concentrations showed higher elastic modulus (EM), ultimate tensile strength (UTS) and ultimate elongation (UE) (p < 0.01) without the need for thermal curing or photocrosslinking. Biological evaluation of these scaffolds showed significantly improved HUVEC attachment and proliferation compared to PCL-only scaffolds (p < 0.05). Thus, we have demonstrated that simple blends of PGS prepolymer with PCL can be used to fabricate microfibrous scaffolds with mechanical properties in the range of a human aortic valve leaflet. PMID:20669260

  2. Improving surface functional properties of tofu whey-derived peptides by chemical modification with fatty acids.

    PubMed

    Matemu, Athanasia Oswald; Katayama, Shigeru; Kayahara, Hisataka; Murasawa, Hisashi; Nakamura, Soichiro

    2012-04-01

    Effect of acylation with saturated fatty acids on surface functional properties of tofu whey-derived peptides was investigated. Tofu whey (TW) and soy proteins (7S, 11S, and acid-precipitated soy protein [APP]) were hydrolyzed by Protease M 'Amano' G, and resulting peptide mixtures were acylated with esterified fatty acids of different chain length (6C to 18C) to form a covalent linkage between the carboxyl group of fatty acid and the free amino groups of peptide. Acylation significantly (P < 0.05) increased emulsifying properties of 7S, 11S, and APP peptides independent of fatty acid chain length. Acylation decreased water binding capacity although oil binding capacity of acylated tofu whey ultra filtered fraction (UFTW < 3 kDa), 7S- and 11S-peptides were improved compared to native peptides. 7S peptides acylated with long chain fatty acids had shown significant higher surface hydrophobicity as in contrast with acylated UFTW < 3 kDa and APP peptides. Fluorescence spectra studies revealed structural conformation of acylated soy peptides as compared to native peptides. This study shows that chemical modification with fatty acids can further affect functional properties of soy proteins.

  3. Inherent Anticipation in the Pharmaceutical and Biotechnology Industries.

    PubMed

    Goldman, Michael; Evans, Georgia; Zappia, Andrew

    2015-04-15

    Pharmaceutical and biotech research often involves discovering new properties of, or new methods to use, existing compositions. The doctrine of inherent anticipation, however, prevents the issuance and/or validity of a patent for discoveries deemed to have been implicitly disclosed in the prior art. This can be a barrier to patent rights in these technologies. Inherent anticipation therefore creates uncertainty for patent protection in the pharmaceutical and biotech sciences. Despite this uncertainty, Federal Circuit jurisprudence provides guidance on the boundaries of the inherent anticipation doctrine. In view of the case law, certain strategies may be employed to protect inventions that may potentially be viewed as inherent in the prior art.

  4. Improvement of water barrier property of paperboard by coating application with biodegradable polymers.

    PubMed

    Han, Jaejoon; Salmieri, Stéphane; Le Tien, Canh; Lacroix, Monique

    2010-03-10

    Biopolymeric coatings were prepared and applied onto paperboard to improve its water barrier property. To prepare whey protein isolate (WPI)/cellulose-based films, WPI and glycerol were dissolved in water with glutaraldehyde (cross-linking agent) and cellulose xanthate. The solution was cast, dried, and insolubilized by entrapment of WPI in regenerated cellulose. Films were combined with beeswax (BW) into a bilayer coating system and then applied onto paperboard by heating compression. Another coating solution consisting of poly(vinyl butyral) (PVB)/zein was prepared by dissolving poly(vinyl alcohol) (PVA) and zein in 70% ethanol with glutaraldehyde and butyraldehyde (functionalization agent). The PVB/zein solution was applied onto paperboard after BW was sprayed. The structure of the PVB/zein-based coatings was analyzed by Fourier transform infrared spectroscopy (FTIR). The water vapor barrier property of coated paperboards was evaluated by water vapor transmission rate (WVTR) measurements. From the FTIR spectra, PVA functionalization after cross-linking and efficient acetalization into PVB were confirmed. WPI/cellulose and PVB/zein coating treatments improved the water barrier properties of paperboard by decreasing the WVTR by 77-78%. Although the BW coating was more efficient (decrease of WVTR by 89%), bilayer coatings composed of BW and polymer coatings had a stronger barrier effect with a decrease of WVTR to 92-95%, hence approaching commercial attributes required to ensure water vapor barrier in paperboard-based food containers (10 g/m(2).day). These results suggest that surface coating by biodegradable polymers may be utilized for the manufacture of paperboard containers in industrial applications.

  5. Improvement of water barrier property of paperboard by coating application with biodegradable polymers.

    PubMed

    Han, Jaejoon; Salmieri, Stéphane; Le Tien, Canh; Lacroix, Monique

    2010-03-10

    Biopolymeric coatings were prepared and applied onto paperboard to improve its water barrier property. To prepare whey protein isolate (WPI)/cellulose-based films, WPI and glycerol were dissolved in water with glutaraldehyde (cross-linking agent) and cellulose xanthate. The solution was cast, dried, and insolubilized by entrapment of WPI in regenerated cellulose. Films were combined with beeswax (BW) into a bilayer coating system and then applied onto paperboard by heating compression. Another coating solution consisting of poly(vinyl butyral) (PVB)/zein was prepared by dissolving poly(vinyl alcohol) (PVA) and zein in 70% ethanol with glutaraldehyde and butyraldehyde (functionalization agent). The PVB/zein solution was applied onto paperboard after BW was sprayed. The structure of the PVB/zein-based coatings was analyzed by Fourier transform infrared spectroscopy (FTIR). The water vapor barrier property of coated paperboards was evaluated by water vapor transmission rate (WVTR) measurements. From the FTIR spectra, PVA functionalization after cross-linking and efficient acetalization into PVB were confirmed. WPI/cellulose and PVB/zein coating treatments improved the water barrier properties of paperboard by decreasing the WVTR by 77-78%. Although the BW coating was more efficient (decrease of WVTR by 89%), bilayer coatings composed of BW and polymer coatings had a stronger barrier effect with a decrease of WVTR to 92-95%, hence approaching commercial attributes required to ensure water vapor barrier in paperboard-based food containers (10 g/m(2).day). These results suggest that surface coating by biodegradable polymers may be utilized for the manufacture of paperboard containers in industrial applications. PMID:20155911

  6. Marble wastes and pig slurry improve the environmental and plant-relevant properties of mine tailings.

    PubMed

    Kabas, S; Faz, A; Acosta, J A; Arocena, J M; Zornoza, R; Martínez-Martínez, S; Carmona, D M

    2014-02-01

    Poor soil fertility is often the biggest challenge to the establishment of vegetation in mine wastes deposits. We conducted field trials in the El Gorguel and El Lirio sites in SE Spain, two representative tailing ponds of similar properties except for pH, to understand the environmental and plant-relevant benefits of marble waste (MW) and pig slurry (PS) applications to mine tailings. Low pH (5.4) tailings (El Lirio) exhibit reduction of up to fourfold in bio-availability of metals as shown by the DTPA-Zn, Pb, water-soluble Zn, Pb and up to 3× for water-soluble Cd. Tailings in El Gorguel have high pH (7.4) and did not exhibit significant trends in the reductions of water-extractable Zn, Pb, Cd and Cu. Improvements to the edaphic (plant-relevant) properties of tailings after the amendments are not as sensitive to pH compared to the environmental characteristics. The two sites had increases in aggregate stability, organic matter (total N and organic C) although total N is higher in the El Gorguel (up to 212 μg N kg(-1)) than the El Lirio (up to 26 μg N kg(-1)). However, cation exchange capacities are similar in both sites at 15.2 cmol(+) kg(-1). We conclude that the characteristics, especially pH, of tailing materials significantly influence the fate of metals but not improvements to plant-relevant properties such as cation exchange capacity and aggregate stability 1 year after the application of MW and PS amendments.

  7. Cyclodextrin Inclusion Complex to Improve Physicochemical Properties of Herbicide Bentazon: Exploring Better Formulations

    PubMed Central

    Yáñez, Claudia; Cañete-Rosales, Paulina; Castillo, Juan Pablo; Catalán, Nicole; Undabeytia, Tomás; Morillo, Esmeralda

    2012-01-01

    The knowledge of the host-guest complexes using cyclodextrins (CDs) has prompted an increase in the development of new formulations. The capacity of these organic host structures of including guest within their hydrophobic cavities, improves physicochemical properties of the guest. In the case of pesticides, several inclusion complexes with cyclodextrins have been reported. However, in order to explore rationally new pesticide formulations, it is essential to know the effect of cyclodextrins on the properties of guest molecules. In this study, the inclusion complexes of bentazon (Btz) with native βCD and two derivatives, 2-hydroxypropyl-β-cyclodextrin (HPCD) and sulfobutylether-β-cyclodextrin (SBECD), were prepared by two methods: kneading and freeze-drying, and their characterization was investigated with different analytical techniques including Fourier transform infrared spectroscopy (FT-IR), differential thermal analysis (DTA), X-ray diffractometry (XRD) and differential pulse voltammetry (DPV). All these approaches indicate that Btz forms inclusion complexes with CDs in solution and in solid state, with a stoichiometry of 1∶1, although some of them are obtained in mixtures with free Btz. The calculated association constant of the Btz/HPCD complex by DPV was 244±19 M−1 being an intermediate value compared with those obtained with βCD and SBECD. The use of CDs significantly increases Btz photostability, and depending on the CDs, decreases the surface tension. The results indicated that bentazon forms inclusion complexes with CDs showing improved physicochemical properties compared to free bentazon indicating that CDs may serve as excipient in herbicide formulations. PMID:22952577

  8. Understanding and Improving High-Temperature Structural Properties of Metal-Silicide Intermetallics

    SciTech Connect

    Bruce S. Kang

    2005-10-10

    The objective of this project was to understand and improve high-temperature structural properties of metal-silicide intermetallic alloys. Through research collaboration between the research team at West Virginia University (WVU) and Dr. J.H. Schneibel at Oak Ridge National Laboratory (ORNL), molybdenum silicide alloys were developed at ORNL and evaluated at WVU through atomistic modeling analyses, thermo-mechanical tests, and metallurgical studies. In this study, molybdenum-based alloys were ductilized by dispersing MgAl2O4 or MgO spinel particles. The addition of spinel particles is hypothesized to getter impurities such as oxygen and nitrogen from the alloy matrix with the result of ductility improvement. The introduction of fine dispersions has also been postulated to improve ductility by acting as a dislocation source or reducing dislocation pile-ups at grain boundaries. The spinel particles, on the other hand, can also act as local notches or crack initiation sites, which is detrimental to the alloy mechanical properties. Optimization of material processing condition is important to develop the desirable molybdenum alloys with sufficient room-temperature ductility. Atomistic analyses were conducted to further understand the mechanism of ductility improvement of the molybdenum alloys and the results showed that trace amount of residual oxygen may be responsible for the brittle behavior of the as-cast Mo alloys. For the alloys studied, uniaxial tensile tests were conducted at different loading rates, and at room and elevated temperatures. Thermal cycling effect on the mechanical properties was also studied. Tensile tests for specimens subjected to either ten or twenty thermal cycles were conducted. For each test, a follow-up detailed fractography and microstructural analysis were carried out. The test results were correlated to the size, density, distribution of the spinel particles and processing time. Thermal expansion tests were carried out using thermo

  9. TRPV4 channel activation improves the tensile properties of self-assembled articular cartilage constructs

    PubMed Central

    Eleswarapu, Sriram V.; Athanasiou, Kyriacos A.

    2012-01-01

    A persistent hurdle in the field of tissue regeneration is to produce tissues with biochemical and biomechanical properties robust enough to meet the aggressive physiological demands of the native milieu. In an effort to improve these properties, tissues grown in vitro are often subjected to mechanical stimuli that aim to recapitulate in vivo physiology. These mechanical stimuli are thought to produce downstream alterations in intracellular ion concentrations, which ultimately give rise to increased biosynthesis. There is mounting evidence that these perturbations in the cellular microenvironment are regulated by the Ca(2+)-permeable transient receptor potential vanilloid 4 (TRPV4) channel. In this study, we examined the effects of targeted TRPV4 activation on self-assembled articular cartilage constructs. The objectives of this study were 1) to determine whether TRPV4 activation would enhance self-assembled constructs, 2) to identify an optimal treatment time window for TRPV4 activation, and 3) to compare TRPV4 activation to Na(+)/K(+) pump inhibition, which has been shown previously to improve construct tensile properties. This study employed a two-phased approach. In Phase I, self-assembled constructs were grown for 4 weeks and subjected to treatment with the TRPV4 agonist 4alpha-phorbol-12,13-didecanoate (4alpha-PDD) during three treatment time windows: t=6-10 days, t=10-14 days, and t=14-18 days. Treatment during t=10-14 days produced an 88% increase in collagen and a 153% increase in tensile stiffness. This treatment window was carried forward to Phase II. In Phase II, we performed a head-to-head comparison between TRPV4 activation using 4alpha-PDD and Na(+)/K(+) pump inhibition using ouabain. Treatment with 4alpha-PDD produced improvements on par with ouabain (91% to 107% increases in tensile stiffness). The results of this study demonstrate the effectiveness of ion channel modulation as a strategy for improving engineered tissues. To our knowledge, this is

  10. Growth Factor Stimulation Improves the Structure and Properties of Scaffold-Free Engineered Auricular Cartilage Constructs

    PubMed Central

    Rosa, Renata G.; Joazeiro, Paulo P.; Bianco, Juares; Kunz, Manuela; Weber, Joanna F.; Waldman, Stephen D.

    2014-01-01

    The reconstruction of the external ear to correct congenital deformities or repair following trauma remains a significant challenge in reconstructive surgery. Previously, we have developed a novel approach to create scaffold-free, tissue engineering elastic cartilage constructs directly from a small population of donor cells. Although the developed constructs appeared to adopt the structural appearance of native auricular cartilage, the constructs displayed limited expression and poor localization of elastin. In the present study, the effect of growth factor supplementation (insulin, IGF-1, or TGF-β1) was investigated to stimulate elastogenesis as well as to improve overall tissue formation. Using rabbit auricular chondrocytes, bioreactor-cultivated constructs supplemented with either insulin or IGF-1 displayed increased deposition of cartilaginous ECM, improved mechanical properties, and thicknesses comparable to native auricular cartilage after 4 weeks of growth. Similarly, growth factor supplementation resulted in increased expression and improved localization of elastin, primarily restricted within the cartilaginous region of the tissue construct. Additional studies were conducted to determine whether scaffold-free engineered auricular cartilage constructs could be developed in the 3D shape of the external ear. Isolated auricular chondrocytes were grown in rapid-prototyped tissue culture molds with additional insulin or IGF-1 supplementation during bioreactor cultivation. Using this approach, the developed tissue constructs were flexible and had a 3D shape in very good agreement to the culture mold (average error <400 µm). While scaffold-free, engineered auricular cartilage constructs can be created with both the appropriate tissue structure and 3D shape of the external ear, future studies will be aimed assessing potential changes in construct shape and properties after subcutaneous implantation. PMID:25126941

  11. Chemistry in the Pharmaceutical Industry

    NASA Astrophysics Data System (ADS)

    Poindexter, Graham S.; Pendri, Yadagiri; Snyder, Lawrence B.; Yevich, Joseph P.; Deshpande, Milind

    This chapter will discuss the role of chemistry within the pharmaceutical industry. Although the focus will be upon the industry within the United States, much of the discussion is equally relevant to pharmaceutical companies based in other first world nations such as Japan and those in Europe. The major objective of the pharmaceutical industry is the discovery, development, and marketing of efficacious and safe drugs for the treatment of human disease. Of course drug companies do not exist as altruistic, charitable organizations but like other share-holder owned corporations within our capitalistic society must achieve profits in order to remain viable and competitive. Thus, there exists a conundrum between the dual goals of enhancing the quality and duration of human life and that of increasing stock-holder equity. Much has been written and spoken in the lay media about the high prices of prescription drugs and the hardships this places upon the elderly and others of limited income.

  12. 36 CFR 51.41 - If the concession contract grants a compensable interest in real property improvements, will the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... contract is an outfitter and guide concession contract? 51.41 Section 51.41 Parks, Forests, and Public... Offeror § 51.41 If the concession contract grants a compensable interest in real property improvements... park area....

  13. 36 CFR 51.41 - If the concession contract grants a compensable interest in real property improvements, will the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... contract is an outfitter and guide concession contract? 51.41 Section 51.41 Parks, Forests, and Public... Offeror § 51.41 If the concession contract grants a compensable interest in real property improvements... park area....

  14. 36 CFR 51.41 - If the concession contract grants a compensable interest in real property improvements, will the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... contract is an outfitter and guide concession contract? 51.41 Section 51.41 Parks, Forests, and Public... Offeror § 51.41 If the concession contract grants a compensable interest in real property improvements... park area....

  15. 36 CFR 51.41 - If the concession contract grants a compensable interest in real property improvements, will the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... contract is an outfitter and guide concession contract? 51.41 Section 51.41 Parks, Forests, and Public... Offeror § 51.41 If the concession contract grants a compensable interest in real property improvements... park area....

  16. 36 CFR 51.41 - If the concession contract grants a compensable interest in real property improvements, will the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... contract is an outfitter and guide concession contract? 51.41 Section 51.41 Parks, Forests, and Public... Offeror § 51.41 If the concession contract grants a compensable interest in real property improvements... park area....

  17. Improved surface property of PVDF membrane with amphiphilic zwitterionic copolymer as membrane additive

    NASA Astrophysics Data System (ADS)

    Li, Jian-Hua; Li, Mi-Zi; Miao, Jing; Wang, Jia-Bin; Shao, Xi-Sheng; Zhang, Qi-Qing

    2012-06-01

    An attempt to improve hydrophilicity and anti-fouling properties of PVDF membranes, a novel amphiphilic zwitterionic copolymer poly(vinylidene fluoride)-graft-poly(sulfobetaine methacrylate) (PVDF-g-PSBMA) was firstly synthesized by atom transfer radical polymerization (ATRP) and used as amphiphilic copolymer additive in the preparation of PVDF membranes. The PVDF-g-PSBMA/PVDF blend membranes were prepared by immersion precipitation process. Fourier transform infrared attenuated reflection spectroscopy (FTIR-ATR) and X-ray photoelectronic spectroscopy (XPS) measurements confirmed that PSBMA brushes from amphiphilic additives were preferentially segregated to membrane-coagulant interface during membrane formation. The morphology of membranes was characterized by scanning electron microscopy (SEM). Water contact angle measurements showed that the surface hydrophilicity of PVDF membranes was improved significantly with the increasing of amphiphilic copolymer PVDF-g-PSBMA in cast solution. Protein static adsorption experiment and dynamic fouling resistance experiment revealed that the surface enrichment of PSBMA brush endowed PVDF blend membrane great improvement of surface anti-fouling ability.

  18. Recent progress in low-voltage cathodoluminescent materials: synthesis, improvement and emission properties.

    PubMed

    Li, Guogang; Lin, Jun

    2014-01-01

    Nowadays there are several technologies used for flat panel displays (FPDs) and the development of FPDs with enhanced energy efficiency and improved display quality is strongly required. Field emission displays (FEDs) have been considered as one of the most promising next generation flat panel display technologies due to their excellent display performance and low energy consumption. For the development of FEDs, phosphors are irreplaceable components. In the past decade, the study of highly efficient low-voltage cathodoluminescent materials, namely FED phosphors, has become the focus of enhancing energy efficiency and realizing high-quality displays. This review summaries the recent progress in the chemical synthesis and improvement of novel, rare-earth and transition metal ions activated inorganic cathodoluminescent materials in powder and thin film forms. The discussion is focused on the modification of morphology, size, surface, composition and conductivity of phosphors and the corresponding effects on their cathodoluminescent properties. Special emphases are given to the selection of host and luminescent centers, the adjustment of emission colors through doping concentration optimization, energy transfer and mono- or co-doping activator ions, the improvement of chromaticity, color stability and color gamut as well as the saturation behavior and the degradation behavior of phosphors under the excitation of a low-voltage electron beam. Finally, the research prospects and future directions of FED phosphors are discussed with recommendations to facilitate the further study of new and highly efficient low-voltage cathodoluminescent materials. PMID:24960634

  19. Improving root-zone soil properties for Trembling Aspen in a reconstructed mine-site soil

    NASA Astrophysics Data System (ADS)

    Dyck, M. F.; Sabbagh, P.; Bockstette, S.; Landhäusser, S.; Pinno, B.

    2014-12-01

    Surface mining activities have significantly depleted natural tree cover, especially trembling aspen (Populus tremuloides), in the Boreal Forest and Aspen Parkland Natural Regions of Alberta. The natural soil profile is usually destroyed during these mining activities and soil and landscape reconstruction is typically the first step in the reclamation process. However, the mine tailings and overburden materials used for these new soils often become compacted during the reconstruction process because they are subjected to high amounts of traffic with heavy equipment. Compacted soils generally have low porosity and low penetrability through increased soil strength, making it difficult for roots to elongate and explore the soil. Compaction also reduces infiltration capacity and drainage, which can cause excessive runoff and soil erosion. To improve the pore size distribution and water transmission, subsoil ripping was carried out in a test plot at Genesee Prairie Mine, Alberta. Within the site, six replicates with two treatments each, unripped (compacted) and ripped (decompacted), were established with 20-m buffers between them. The main objective of this research was to characterize the effects of subsoil ripping on soil physical properties and the longevity of those effects.as well as soil water dynamics during spring snowmelt. Results showed improved bulk density, pore size distribution and water infiltration in the soil as a result of the deep ripping, but these improvements appear to be temporary.

  20. Improving the installation of renewable heating technology in UK social housing properties through user centred design

    PubMed Central

    Moore, Natalie; Lilley, Debra

    2015-01-01

    Social housing organisations are increasingly installing renewable energy technologies, particularly for the provision of heating and hot water. To meet carbon reduction targets, uptake and installation must allow occupants to use the technology effectively. This paper describes research which investigated the service of installing heat pumps into UK social housing properties, from both landlords’ and tenants’ experiences. Adopting a user centred design approach, the research was in three phases: an exploration study to investigate landlords’ and tenants’ experiences of heat pump installation and use; refinement and development of the requirements for improved service delivery, primarily technology introduction and control; and the development and initial evaluation of an information leaflet as a key touchpoint in the service delivery. Recommendations for improved service delivery, to enable heat pumps to be accepted and used more effectively, are presented, as well as reflection on the process of applying user centred design in this context. In a relatively immature area of industry, installations to date have been heavily focused on technical aspects. This paper provides an insight into the human aspects of the service delivery of heat pumps in social housing, providing designers and social housing landlords with insight about how to improve the service. PMID:26539060

  1. Sorghum mutant RG displays antithetic leaf shoot lignin accumulation resulting in improved stem saccharification properties

    PubMed Central

    2013-01-01

    Background Improving saccharification efficiency in bioenergy crop species remains an important challenge. Here, we report the characterization of a Sorghum (Sorghum bicolor L.) mutant, named REDforGREEN (RG), as a bioenergy feedstock. Results It was found that RG displayed increased accumulation of lignin in leaves and depletion in the stems, antithetic to the trend observed in wild type. Consistent with these measurements, the RG leaf tissue displayed reduced saccharification efficiency whereas the stem saccharification efficiency increased relative to wild type. Reduced lignin was linked to improved saccharification in RG stems, but a chemical shift to greater S:G ratios in RG stem lignin was also observed. Similarities in cellulose content and structure by XRD-analysis support the correlation between increased saccharification properties and reduced lignin instead of changes in the cellulose composition and/or structure. Conclusion Antithetic lignin accumulation was observed in the RG mutant leaf-and stem-tissue, which resulted in greater saccharification efficiency in the RG stem and differential thermochemical product yield in high lignin leaves. Thus, the red leaf coloration of the RG mutant represents a potential marker for improved conversion of stem cellulose to fermentable sugars in the C4 grass Sorghum. PMID:24103129

  2. Recent progress in low-voltage cathodoluminescent materials: synthesis, improvement and emission properties.

    PubMed

    Li, Guogang; Lin, Jun

    2014-01-01

    Nowadays there are several technologies used for flat panel displays (FPDs) and the development of FPDs with enhanced energy efficiency and improved display quality is strongly required. Field emission displays (FEDs) have been considered as one of the most promising next generation flat panel display technologies due to their excellent display performance and low energy consumption. For the development of FEDs, phosphors are irreplaceable components. In the past decade, the study of highly efficient low-voltage cathodoluminescent materials, namely FED phosphors, has become the focus of enhancing energy efficiency and realizing high-quality displays. This review summaries the recent progress in the chemical synthesis and improvement of novel, rare-earth and transition metal ions activated inorganic cathodoluminescent materials in powder and thin film forms. The discussion is focused on the modification of morphology, size, surface, composition and conductivity of phosphors and the corresponding effects on their cathodoluminescent properties. Special emphases are given to the selection of host and luminescent centers, the adjustment of emission colors through doping concentration optimization, energy transfer and mono- or co-doping activator ions, the improvement of chromaticity, color stability and color gamut as well as the saturation behavior and the degradation behavior of phosphors under the excitation of a low-voltage electron beam. Finally, the research prospects and future directions of FED phosphors are discussed with recommendations to facilitate the further study of new and highly efficient low-voltage cathodoluminescent materials.

  3. THE ROLE OF MAMMALIAN DATA IN DETERMINING PHARMACEUTICAL RESPONSES IN AQUATIC SPECIES

    EPA Science Inventory

    Human pharmaceuticals are designed to be biologically active, and are extensively studies for physicalchemical, pharmacological, and toxicological properties. In those studies, efficacy and safety endpoints ED50s, LCSOs, NOAELs, LOAELs, etc.) are linked to plasma exposures (Cmax ...

  4. Improvement of mechanical properties of polymeric composites: Experimental methods and new systems

    NASA Astrophysics Data System (ADS)

    Nguyen, Felix Nhanchau

    Filler- (e.g., particulate or fiber) reinforced structural polymers or polymeric composites have changed the way things are made. Today, they are found, for example, in air/ground transportation vehicles, sporting goods, ballistic barrier applications and weapons, electronic packaging, musical instruments, fashion items, and more. As the demand increases, so does the desire to have not only well balanced mechanical properties, but also light weight and low cost. This leads to a constant search for novel constituents and additives, new fabrication methods and analytical techniques. To achieve new or improved composite materials requires more than the identification of the right reinforcements to be used with the right polymer matrix at the right loading. Also, an optimized adhesion between the two phases and a toughened matrix system are needed. This calls for new methods to predict, modify and assess the level of adhesion, and new developments in matrix tougheners to minimize compromises in other mechanical/thermal properties. Furthermore, structural optimization, associated with fabrication (e.g., avoidance of fiber-fiber touching or particle aggregation), and sometimes special properties, such as electrical conductivity or magnetic susceptibility are necessary. Finally, the composite system's durability, often under hostile conditions, is generally mandatory. The present study researches new predictive and experimental methods for optimizing and characterizing filler-matrix adhesion and develops a new type of epoxy tougheners. Specifically, (1) a simple thermodynamic parameter evaluated by UNIFAC is applied successfully to screen out candidate adhesion promoters, which is necessary for optimization of the physio-chemical interactions between the two phases; (2) an optical-acoustical mechanical test assisted with an acoustic emission technique is developed to de-convolute filler debonding/delamination among many other micro failure events, and (3) novel core

  5. Using spectral subspaces to improve infrared spectroscopy prediction of soil properties

    NASA Astrophysics Data System (ADS)

    Sila, Andrew; Shepherd, Keith D.; Pokhariyal, Ganesh P.; Towett, Erick; Weullow, Elvis; Nyambura, Mercy K.

    2015-04-01

    We propose a method for improving soil property predictions using local calibration models trained on datasets in spectral subspaces rather that in a global space. Previous studies have shown that local calibrations based on a subset of spectra based on spectral similarity can improve model prediction performance where there is large population variance. Searching for relevant subspaces within a spectral collection to construct local models could result in models with high power and small prediction errors, but optimal methods for selection of local samples are not clear. Using a self-organizing map method (SOM) we obtained four mid-infrared subspaces for 1,907 soil sample spectra collected from 19 different countries by the Africa Soil Information Service. Subspace means for four sub-spaces and five selected soil properties were: pH, 6.0, 6.1, 6.0, 5.6; Mehlich-3 Al, 358, 974, 614, 1032 (mg/kg); Mehlich-3 Ca, 363, 1161, 526, 4276 (mg/kg); Total Carbon, 0.4, 1.1, 0.6, 2.3 (% by weight), and Clay (%), 16.8, 46.4, 27.7, 63.3. Spectral subspaces were also obtained using a cosine similarity method to calculate the angle between the entire sample spectra space and spectra of 10 pure soil minerals. We found the sample soil spectra to be similar to four pure minerals distributed as: Halloysite (n1=214), Illite (n2=743), Montmorillonite (n3=914) and Quartz (n4=32). Cross-validated partial least square regression models were developed using two-thirds of samples spectra from each subspace for the five soil properties.We evaluated prediction performance of the models using the root mean square error of prediction (RMSEP) for a one-third-holdout set. Local models significantly improved prediction performance compared with the global model. The SOM method reduced RMESP for total carbon by 10 % (global RMSEP = 0.41) Mehlich-3 Ca by 17% (global RMESP = 1880), Mehlich-3 Al by 21 % (global RMSEP = 206), and clay content by 6 % (global RMSEP = 13.6), but not for pH. Individual SOM

  6. Climate-Relevant Properties of Particles Generated by Traditional and Improved Wood Burning Cook Stoves

    NASA Astrophysics Data System (ADS)

    Roden, C. A.; Bond, T. C.; Conway, S.; Osorto Pinel, B.; Maccarty, N.; Still, D.

    2005-12-01

    Some 2-3 billion people in the world use biofuel as their primary energy source for domestic fuel needs. It is estimated that the combustion of biofuel generates 20% of all carbonaceous aerosols. Uncertainty about the quantity of negative (cooling) radiative forcing generated by aerosols contributes greatly to our lack of understanding of the complete climate picture. In order to facilitate measurements of poorly characterized aerosol sources at a wide range of potential sampling sites, we designed and built an Ambulatory, Real-time ANalyzer for Aerosols or ARANA. The ARANA measures the following real-time data: absorption at three wavelengths, scattering, CO concentration, and CO2 concentration. Additionally, the sampling system captures particles on filters for later analysis. The goals of this project are 1) to gain further understanding of the properties of aerosols generated from biofuels during actual cooking events, which may vary from laboratory testing 2) Determine the factors which govern the emissions from cookstoves so that we can represent these highly variable sources in emission models 3) quantitatively assess improved cookstoves, in order to improve the design and determine the lowest emission model. In Honduras during the summers of 2005 and 2004, we measured real-time emissions from four different improved cookstoves with five tests for each type of improved stove; as well as the emissions from 12 traditional Honduran cookstoves. We observed that particles produced during different combustion phases have very different optical properties. The fire startup and fuel addition phases generally produced the most aerosols, with large quantities of very dark particles having a single scatter albedo between 0.3 and 0.5. For most tests, the single scatter albedo averaged around 0.55 indicating that the primary particles are climate warming. We summarize the characteristics of the particles emitted during cooking events, examining the single scatter albedo

  7. Improving the Performance and Antifouling Properties of Thin-Film Composite Membranes for Water Separation Technologies

    NASA Astrophysics Data System (ADS)

    Tiraferri, Alberto

    Membrane-based water separation processes utilize semi-permeable membranes to retain dissolved solids and contaminants. Deployment of these technologies for desalination and wastewater reuse has the potential to sustainably increase the supply of potable, agricultural, and industrial water. Despite considerable development of semi-permeable membranes in the last decades, several design obstacles hampering their progress have yet to be overcome. Specifically, major membrane improvements are currently sought with respect to their performance and productivity, as well as their resistance to fouling. This dissertation research aims at the advancement of semi-permeable membranes by rational optimization of their design to: (i) understand and improve their transport properties and (ii) reduce fouling by organic molecules and delay biofouling by microorganisms. In particular, thin-film composite polyamide membranes for both reverse osmosis and forward osmosis processes are the main target of the investigation. The structural and physicochemical properties of thin-film composite membranes are both characterized and tailored through implementation of original techniques and novel functionalization protocols. The membrane structure and morphology are rationally modified to enhance the mass transport within the support layer. The influence of fabrication conditions on support layer formation and on its final structure is elucidated. The intricate interrelationship among the performance of the different layers of the composite membrane is highlighted and a new protocol is developed to characterize the transport properties of membranes deployed in forward osmosis processes. Novel approaches to impart targeted properties to the active surface of thin-film composite membranes are also proposed. The functionalization is achieved by exploiting the inherent moieties of the polyamide layer to irreversibly bind nanomaterials with desired properties. An experimental method to determine

  8. Improvement of thermoelectric properties for half-Heusler TiNiSn by interstitial Ni defects

    SciTech Connect

    Hazama, Hirofumi; Matsubara, Masato; Asahi, Ryoji; Takeuchi, Tsunehiro

    2011-09-15

    We have synthesized off-stoichiometric Ti-Ni-Sn half-Heusler thermoelectrics in order to investigate the relation between randomly distributed defects and thermoelectric properties. A small change in the composition of Ti-Ni-Sn causes a remarkable change in the thermal conductivity. An excess content of Ni realizes a low thermal conductivity of 2.93 W/mK at room temperature while keeping a high power factor. The low thermal conductivity originates in the defects generated by an excess content of Ni. To investigate the detailed defect structure, we have performed first-principles calculations and compared with x ray photoemission spectroscopy measurement. Based on these analyses, we conclude that the excess Ni atoms randomly occupy the vacant sites in the half-Heusler structure, which play as phonon scattering centers, resulting in significant improvement of the figure of merit without any substitutions of expensive heavy elements, such as Zr and Hf.

  9. Fluorescence upconversion properties of a class of improved pyridinium dyes induced by two-photon absorption

    NASA Astrophysics Data System (ADS)

    Xu, Guibao; Hu, Dawei; Zhao, Xian; Shao, Zongshu; Liu, Huijun; Tian, Yupeng

    2007-06-01

    We report the fluorescence upconversion properties of a class of improved pyridinium toluene- p-sulfonates having donor- π-acceptor (D- π-A) structure under two-photon excitation at 1064 nm. The experimental results show that both the two-photon excited (TPE) fluorescence lifetime and the two-photon pumped (TPP) energy upconversion efficiency were increased with the enhancement of electron-donating capability of the donor in the molecule. It is also indicated that an overlong alkyl group tends to result in a weakened molecular conjugation, leading to a decreased two-photon absorption (TPA) cross section. By choosing the donor, we can obtain a longest fluorescence lifetime of 837 ps, a highest energy upconversion efficiency of ˜6.1%, and a maximum TPA cross-section of 8.74×10 -48 cm 4 s/photon in these dyes.

  10. Improved nonlinear slot waveguides using dielectric buffer layers: properties of TM waves.

    PubMed

    Elsawy, Mahmoud M R; Renversez, Gilles

    2016-04-01

    We propose an improved version of the symmetric metal slot waveguides with a Kerr-type nonlinear dielectric core adding linear dielectric buffer layers between the metal regions and the core. Using a finite element method to compute the stationary nonlinear modes, we provide the full phase diagrams of its main transverse magnetic modes as a function of the total power, buffer layer, and core thicknesses that are more complex than the ones of the simple nonlinear metal slot. We show that these modes can exhibit spatial transitions toward specific modes of the new structure as a function of power. We also demonstrate that, for the main modes, the losses are reduced compared to the previous structures, and that they can now decrease with power. Finally, we describe the stability properties of the main stationary solutions using nonlinear FDTD simulations. PMID:27192282

  11. Improved Mechanical Properties of Various Fabric-Reinforced Geocomposite at Elevated Temperature

    NASA Astrophysics Data System (ADS)

    Samal, Sneha; Phan Thanh, Nhan; Petríková, Iva; Marvalová, Bohadana

    2015-07-01

    This article signifies the improved performance of the various types of fabric reinforcement of geopolymer as a function of physical, thermal, mechanical, and heat-resistant properties at elevated temperatures. Geopolymer mixed with designed Si:Al ratios of 15.6 were synthesized using three different types of fabric reinforcement such as carbon, E-glass, and basalt fibers. Heat testing was conducted on 3-mm-thick panels with 15 × 90 mm surface exposure region. The strength of carbon-based geocomposite increased toward a higher temperature. The basalt-reinforced geocomposite strength decreased due to the catastrophic failure in matrix region. The poor bridging effect and dissolution of fabric was observed in the E-glass-reinforced geocomposite. At an elevated temperature, fiber bridging was observed in carbon fabric-reinforced geopolymer matrix. Among all the fabrics, carbon proved to be suitable candidate for the high-temperature applications in thermal barrier coatings and fire-resistant panels.

  12. Improvement of texture properties and flavor of frozen dough by carrot (Daucus carota) antifreeze protein supplementation.

    PubMed

    Zhang, Chao; Zhang, Hui; Wang, Li; Gao, Hong; Guo, Xiao Na; Yao, Hui Yuan

    2007-11-14

    The effects of concentrated carrot protein (CCP) containing 15.4% (w/w) carrot (Daucus carota) antifreeze protein on texture properties of frozen dough and volatile compounds of crumb were studied. CCP supplementation lowered the freezable water content of the dough, resulting in some beneficial effects including holding loaf volume steadily and making the dough softer and steadier during frozen storage. Furthermore, SPME-GC-MS analysis showed CCP supplementation did not give any negative influences on volatile compounds of crumb and gave a pleasant aroma felt like Michelia alba DC from trans-caryophyllene simultaneously. Combining our previous results that CCP supplementation improves the fermentation capacity of the frozen dough, CCP could be used as a beneficial additive for frozen dough processing. PMID:17935294

  13. Mo doped DLC nanocomposite coatings with improved mechanical and blood compatibility properties

    NASA Astrophysics Data System (ADS)

    Tang, X. S.; Wang, H. J.; Feng, L.; Shao, L. X.; Zou, C. W.

    2014-08-01

    Mo (molybdenum) doped diamond like carbon (Mo-DLC) coatings with improved mechanical and blood compatibility properties were deposited by closed field unbalanced magnetron sputtering. The undoped and Mo-doped DLC coatings were analyzed by various characterization techniques such as Raman spectra, Atomic force microscopy, and temperature-dependent frictional wear testing. The results showed that the Mo-DLC coating with low Mo concentration was a effective protective coating with reduced residual stress and increased cohesive strength, and kept good wear resistance at the ambient temperature of 500 °C. The blood compatibility of Mo-DLC coatings was investigated by platelet adhesion. The results showed that the amount of thrombus on the Mo-DLC nanocomposite coatings was much less than that of thrombus on pyrolytic carbon films. The Mo-DLC nanocomposite coatings would be a new kind of promising materials applied to artificial heart valve and endovascula stent.

  14. Development of hybrid cotton/hydrogel yarns with improved absorption properties for biomedical applications.

    PubMed

    Pollini, Mauro; Paladini, Federica; Sannino, Alessandro; Maffezzoli, Alfonso

    2016-06-01

    Hyperhidrosis, or excessive sweating, is an overlooked and potentially disabling symptom, which is often seen in social anxiety disorder. In this work an innovative advanced textile material was developed for application in the management of excessive sweating, preparing a drying yarn providing improved comfort. Hybrid cotton/hydrogel yarns were obtained by combining cotton with superabsorbent hydrogels through an optimization study focused on the achievement of the most promising product in terms of absorption properties and resistance to washings. Swelling and washing tests were performed using different hydrogels, and the effect of an additional crosslinking on the materials was also evaluated by testing different solutions containing Al(3+) and Ca(2+) ions. Scanning electron microscopy and infrared spectroscopy analyses were adopted to characterize morphology and chemical structure of the hydrogels undergoing different production processes. The biocompatibility of the hybrid fabrics was demonstrated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide colorimetric assay (MTT) through the extract method.

  15. Improvement of the luminescent properties of cadmium sulfide quantum dots by a post-synthesis modification

    NASA Astrophysics Data System (ADS)

    López, Israel; Gómez, Idalia

    2014-11-01

    Here the improvement of the luminescent properties of CdS quantum dots by a post-synthesis modification with aqueous solutions of NaOH at different concentrations is presented. The CdS quantum dots were synthesized by a microwave-assisted method using citrate ions as stabilizer. The addition of the hydroxide ions increased the intensity of the orange-red emission by about 80%. Besides, a violet-blue emission was achieved by means of this post-synthesis modification. The hydroxide ions control the precipitation equilibria of the CdS and Cd(OH)2, dissolving and precipitating the surface of the quantum dots. The NaOH treatment increases the number of traps, which produces less band-edge and more deep-trap emission, which explains the decrease and increase in the intensity of the violet-blue and orange-red emissions, respectively.

  16. Improvement of electrical properties of through silicon vias metal interconnector by adding single-walled nanotubes

    NASA Astrophysics Data System (ADS)

    Geon Jung, Dong; Sung, Byung Mok; Kong, Seong Ho

    2015-06-01

    A novel through silicon via (TSV) interconnector, which consists of tin (Sn) powder and single-walled nanotube (SWNT) powder, is proposed and characterized. Most conventional TSV structures, which are commercially available to integrate multiple chips on one packaging, utilize electroplated copper as the interconnector. However, the electroplating-based process has some drawbacks, such as highly demanding fabrication processes in high-aspect-ratio vias, numerous voids, and high cost. To avoid these issues, we used Sn powder mixed with SWNTs as TSV interconnector. SWNTs have been added to improve the electrical properties of TSVs filled only with Sn. The electrical resistance of Sn powder-filled TSVs is 44.59 Ω, but it is markedly decreased to 5 Ω when a Sn and SWNTs mixture (weight ratio of \\text{SWNTs}:\\text{Sn} = 0.5:1) was used as the TSV interconnector. In addition, the proposed method could be used for various applications owing to its low process temperature.

  17. Improved electrical and optical properties of Poly(3,4-ethylenedioxythiophene) via ordered microstructure

    NASA Astrophysics Data System (ADS)

    Feng, Wei; Li, Yu; Wu, Jun; Noda, Hideki; Fujii, Akihiko; Ozaki, Masanori; Yoshino, Katsumi

    2007-05-01

    Poly(3,4-ethylenedioxythiophene) (PEDOT) nanorods (80-150 nm in diameter) and nanospheres were synthesized through a self-assembly method using ferric chloride (FeCl3) and ammonium persulfate (APS) as oxidants, respectively, and camphorsulfonic acid (CSA) as the dopant. The PEDOT nanorods showed broader absorption bands, higher crystallinity and much higher room-temperature conductivity (approximately 300 S cm-1) than the PEDOT nanospheres. Such obviously distinct properties of these products were considered to be due to the much lower rate of polymerization with FeCl3 than APS, which made the growth of PEDOT according to the suggested cylinder micelles more moderate and regular; as a result, the morphology of the microstructure changed and the crystallinity, the doping level, the molecular orderliness and the conductivity of PEDOT synthesized under lower rate of polymerization improved intensely at the same time.

  18. Improved photoluminescence property of CTAB assisted polyaniline-AlZnO nanocomposite

    SciTech Connect

    Mitra, Mousumi; Banerjee, Dipali; Kargupta, Kajari; Ganguly, Saibal

    2015-06-24

    Polyaniline-Al doped ZnO ((PANI-AlZnO:: 70:30) nanocomposite was prepared via in situ chemical oxidative polymerization, while the hexagonal powder of AlZnO was synthesized via sol-gel technique, using Hexadecyltrimethylammonium bromide (CTAB) as a capping agent. The prepared nanocomposite was characterized by High resolution transmission electron microscopy (HRTEM), EDAX, X-ray diffraction (XRD) and Fourier transforms infrared (FTIR) spectra. The optical property of the nanomaterials is examined by photoluminescence (PL) spectra analysis. The XRD pattern confirms the formation of Al doped ZnO as well as PANI. The HRTEM images of the composite showed the formation of hexagonal AlZnO embedded in polyaniline matrix. EDAX spectrum shows the compositional analysis of the nanocomposite. FTIR spectra confirm the formation of nanocomposite of PANI and hexagonal AlZnO. The PL intensity of the nanocomposite is improved as compared to pure AlZnO.

  19. Shutdown-functionalized nonwoven separator with improved thermal and electrochemical properties for lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Kim, Youngkwon; Lee, Won-Yeol; Kim, Ki Jae; Yu, Ji-Sang; Kim, Young-Jun

    2016-02-01

    A shutdown-functionalized nonwoven separator (SFNS) with improved thermal and electrochemical stabilities is prepared by a simple dip coating method for use in lithium-ion battery (LiB) applications. The SFNS shows thermal stability at 200 °C, while providing shutdown functionality at approximately 140 °C, similar to commercial porous polyethylene separators. The surface-coated polymer prevents leakage current problems and in addition, shows air permeability values similar to that of bare nonwoven separators, while maintaining a thickness of about 20 μm, which is a desired attribute of effective separators for LiBs. The SFNS also shows increased electrolyte uptake and higher conductivity, compared to a bare polyethylene separator. Therefore, a cell with the SFNS exhibits higher discharge capacity and better cycle property than that with a porous polyethylene separator. These results suggest that SFNS is an effective separator for high-performance LiBs.

  20. [New transparency between physicians and the pharmaceutical industry].

    PubMed

    Bühmann, W

    2014-08-01

    The long-lasting trusting partnership between physicians and the pharmaceutical industry with respect to experience from applied research of medications and vocational training, was severely tested by campaign-like dissemination of collective accusations of corruption. Instead of standing by their responsibility to financing clinical research and vocational training of physicians, the health insurance companies in particular claim that physicians are being extensively bribed by the pharmaceutical industry. In order to continuously improve the mutual targets, i.e. the treatment options for patients, both groups have developed transparency regulations.

  1. Endocrine-Active Pharmaceuticals: An Environmental Concern?

    EPA Science Inventory

    Recently, there has been growing interest in pharmaceuticals that are specifically designed to have endocrine activity, such as the estrogens used in birth control pills, exerting unintended effects on fish and other aquatic organisms. These pharmaceuticals may not be persistent...

  2. High performance hyperbranched polymers for improved processing and mechanical properties in thermoset composites

    NASA Astrophysics Data System (ADS)

    Marsh, Timothy

    Hyperbranched polymers, specifically hyperbranched poly(arylene ether ketone imide)s (HBPAEKI), are here studied as blend additives in thermoset composites to improve processing and ultimate performance properties of the composite. Monomer synthesis for HBPAEKI was further advanced in this work leading to higher yields, fewer reactions, and shorter production times. A five step synthetic method with an overall yield of 12% was reduced to a three step process with an overall yield of 38%. Polymer was synthesized under varying conditions and end group chemistry for use in thermoset blends. NMR characterization allowed for the assignment of chemical shifts in monomer and cataloguing of shifts in polymer for use in future work to characterize degree of branching. Cure kinetics of blends of HBPAEKI are explored through the use of differential scanning calorimetry (DSC) and chemorheology using small angle oscillatory shear. In a phenylethynyl terminated imide oligomer (PETI) thermoset resin, reactive phenylethynyl endcapped PAEKI (PEPAEKI) was found to retard cure while non reactive alkyl endcapped PAEKI was found to accelerate cure in DGEBA/DAH epoxy systems. Minimal effect was seen on early stage blend viscosity. Composite properties tested focused on the effect on bulk fracture and interfacial shear strength. No significant effect was seen in fracture toughness by SENB. XPS was used to verify that PEPAEKI was surface active to DGEBA/DDS epoxy/air interfaces to the complete exclusion of the epoxy at the surface. Evidence was also seen consistent with surface activity in alkyl endcapped PAEKI in DGEBA/DAH systems, although the contrast is much lower. Effect of alkyl endcapped HBPAEKI on interfacial shear strength was examined through the use of t-peel and single fiber fracture (SFF) techniques. In some systems, t-peel indicates a clear improvement in peel force, proportional to the blend concentration. In SFF, interfacial shear strength was found to be equal or slightly

  3. Regulation of Isotopic Composition of Water - way of Improvement of Cosmonauts Drinking Water Functional Properties

    NASA Astrophysics Data System (ADS)

    Kulikova, Ekaterina; Utina, Dina; Vorozhtsova, Svetlana; Severyuhin, Yuri; Abrosimova, Anna; Sinyak, Yuri; Ivanov, Alexander

    The problem in providing drinking water to cosmonauts is solved - at this moment there is a task to improve the functional properties of the water. One of the perspectives of this trend is the use of light isotopic water. The animal studies have shown that long-term consumption of water with a depletion of deuterium and oxygen heavy isotopes accelerates the rise of mass non-irradiated mice, the phase fluctuations reducing or increasing hematological parameters were having adaptive nature. These fluctuations didn’t overcome values beyond the physiological norm of this type of animal. It is established that the therapeutic use of light isotopic water with 35 - 90 ppm in deuterium increases the survival of irradiated mice by an average of 30%, contributes to the preservation of irradiated animals body weight. Treatment of acute radiation sickness with light isotopic water stimulates hematopoietic recovery. At the same time, keeping mice drinking light isotopic water for 7 - 8 days before the irradiation (from 4 to 8.5 Gr) has no effect on the level of radio resistance. Longer keeping mice on light isotopic water, for 14 -21 days - reduction in life expectancy, animal mass, bone marrow cellularity and the level of white blood cells in irradiated animals is noted. It was established that keeping mice on light isotopic water for 14 days before exposure in experimental animals causes an increase in the mitotic index and the frequency of formation of aberrant mitosis after 24 hours of Co(60) gamma radiation in doses of 1 , 2, and 4 Gr. Thus, it is clear that the regulation of the isotopic composition of drinking water - way to improve its functional properties.

  4. A terahertz time-domain study on the estimation of opto-mechanical properties of pharmaceutical tablets using the Hashin-Shtrikman bounds for refractive index: a case study of microcrystalline cellulose and starch acetate compacts

    NASA Astrophysics Data System (ADS)

    Bawuah, Prince; Peiponen, Kai-Erik

    2016-06-01

    This work highlights the use of Hashin-Shtrikman (H-S) bounds in the prediction and verification of the effective refractive index, the height and the Young's modulus of given training sets of pharmaceutical compacts using the measured time delay of a THz pulse traversing the compacts. Set A consisted of 13 microcrystalline cellulose (MCC) compacts whereas set B was made up of 5 starch acetate (SA) compacts. MCC is a typical ingredient of many pharmaceutical tablets. In the case of the MCC compacts, tight and closely matched bounds were obtained between the experimental, the calculated upper, lower bound values for the effective refractive index, and the height values. This promising outcome has shown the high possibility of utilizing H-S bounds in the verification and prediction of the decision level of useful parameters, which can serve as a quality check for pharmaceutical tablets. For the SA compacts, although less tight bounds were observed, the experimental values for the effective refractive index and the Young's modulus were closely matched with the upper and the lower bounds, respectively. We therefore speculate based on the above observations that the MCC tablets contain an almost evenly distributed spherically shaped air voids whereas in the SA compacts, this assumption might not necessary be true.

  5. Polylactide/Poly(ω-hydroxytetradecanoic acid) Reactive Blending: A Green Renewable Approach to Improving Polylactide Properties.

    PubMed

    Spinella, Stephen; Cai, Jiali; Samuel, Cedric; Zhu, Jianhui; McCallum, Scott A; Habibi, Youssef; Raquez, Jean-Marie; Dubois, Philippe; Gross, Richard A

    2015-06-01

    A green manufacturing technique, reactive extrusion (REx), was employed to improve the mechanical properties of polylactide (PLA). To achieve this goal, a fully biosourced PLA based polymer blend was conceived by incorporating small quantities of poly(ω-hydroxytetradecanoic acid) (PC14). PLA/PC14 blends were compatibilized by transesterification reactions promoted by 200 ppm titanium tetrabutoxide (Ti(OBu)4) during REx. REx for 15 min at 150 rpm and 200 °C resulted in enhanced blend mechanical properties while minimizing losses in PLA molecular weight. SEM analysis of the resulting compatibilized phase-separated blends showed good adhesion between dispersed PC14 phases within the continuous PLA phase. Direct evidence for in situ synthesis of PLA-b-PC14 copolymers was obtained by HMBC and HSQC NMR experiments. The size of the dispersed phase was tuned by the screw speed to "tailor" the blend morphology. In the presence of 200 ppm Ti(OBu)4, inclusion of only 5% PC14 increased the elongation at break of PLA from 3 to 140% with only a slight decrease in the tensile modulus (3200 to 2900 MPa). Furthermore, PLA's impact strength was increased by 2.4× that of neat PLA for 20% PC14 blends prepared by REx. Blends of PLA and PC14 are expected to expand the potential uses of PLA-based materials. PMID:25848833

  6. Poly(3-hydroxybutyrate)/ZnO Bionanocomposites with Improved Mechanical, Barrier and Antibacterial Properties

    PubMed Central

    Díez-Pascual, Ana M.; Díez-Vicente, Angel L.

    2014-01-01

    Poly(3-hydroxybutyrate) (PHB)-based bionanocomposites incorporating different contents of ZnO nanoparticles were prepared via solution casting technique. The nanoparticles were dispersed within the biopolymer without the need for surfactants or coupling agents. The morphology, thermal, mechanical, barrier, migration and antibacterial properties of the nanocomposites were investigated. The nanoparticles acted as nucleating agents, increasing the crystallization temperature and the degree of crystallinity of the matrix, and as mass transport barriers, hindering the diffusion of volatiles generated during the decomposition process, leading to higher thermal stability. The Young’s modulus, tensile and impact strength of the biopolymer were enhanced by up to 43%, 32% and 26%, respectively, due to the strong matrix-nanofiller interfacial adhesion attained via hydrogen bonding interactions, as revealed by the FT-IR spectra. Moreover, the nanocomposites exhibited reduced water uptake and superior gas and vapour barrier properties compared to neat PHB. They also showed antibacterial activity against both Gram-positive and Gram-negative bacteria, which was progressively improved upon increasing ZnO concentration. The migration levels of PHB/ZnO composites in both non-polar and polar simulants decreased with increasing nanoparticle content, and were well below the current legislative limits for food packaging materials. These biodegradable nanocomposites show great potential as an alternative to synthetic plastic packaging materials especially for use in food and beverage containers and disposable applications. PMID:24941255

  7. Improving N(6)-methyladenosine site prediction with heuristic selection of nucleotide physical-chemical properties.

    PubMed

    Zhang, Ming; Sun, Jia-Wei; Liu, Zi; Ren, Ming-Wu; Shen, Hong-Bin; Yu, Dong-Jun

    2016-09-01

    N(6)-methyladenosine (m(6)A) is one of the most common and abundant post-transcriptional RNA modifications found in viruses and most eukaryotes. m(6)A plays an essential role in many vital biological processes to regulate gene expression. Because of its widespread distribution across the genomes, the identification of m(6)A sites from RNA sequences is of significant importance for better understanding the regulatory mechanism of m(6)A. Although progress has been achieved in m(6)A site prediction, challenges remain. This article aims to further improve the performance of m(6)A site prediction by introducing a new heuristic nucleotide physical-chemical property selection (HPCS) algorithm. The proposed HPCS algorithm can effectively extract an optimized subset of nucleotide physical-chemical properties under the prescribed feature representation for encoding an RNA sequence into a feature vector. We demonstrate the efficacy of the proposed HPCS algorithm under different feature representations, including pseudo dinucleotide composition (PseDNC), auto-covariance (AC), and cross-covariance (CC). Based on the proposed HPCS algorithm, we implemented an m(6)A site predictor, called M6A-HPCS, which is freely available at http://csbio.njust.edu.cn/bioinf/M6A-HPCS. Experimental results over rigorous jackknife tests on benchmark datasets demonstrated that the proposed M6A-HPCS achieves higher success rates and outperforms existing state-of-the-art sequence-based m(6)A site predictors. PMID:27293216

  8. Method for improving the mechanical properties of uranium-1 to 3 wt % zirconium alloy

    DOEpatents

    Anderson, R.C.

    1983-11-22

    A uranium-1 to 3 wt % zirconium alloy characterized by high strength, high ductility and stable microstructure is fabricated by an improved thermal mechanical process. A homogenous ingot of the alloy which has been reduced in thickness of at least 50% in the two-step forging operation, rolled into a plate with a 75% reduction and then heated in vacuum at a temperature of about 750 to 850/sup 0/C and then quenched in water, is subjected to further thermal-mechanical operation steps to increase the compressive yield strength approximately 30%, stabilize the microstructure, and decrease the variations in mechanical properties throughout the plate is provided. These thermal-mechanical steps are achieved by cold rolling the quenchd plate to reduce the thickness thereof about 8 to 12%, aging the cold rolled plate at a first temperature of about 325 to 375/sup 0/C for five to six hours and then aging the plate at a higher temperature ranging from 480 to 500/sup 0/C for five to six hours prior to cooling the billet to ambient conditions and sizing the billet or plate into articles provides the desired increase in mechanical properties and phase stability throughout the plate.

  9. Introducing improved structural properties and salt dependence into a coarse-grained model of DNA

    SciTech Connect

    Snodin, Benedict E. K. Mosayebi, Majid; Schreck, John S.; Romano, Flavio; Doye, Jonathan P. K.; Randisi, Ferdinando; Šulc, Petr; Ouldridge, Thomas E.; Tsukanov, Roman; Nir, Eyal; Louis, Ard A.

    2015-06-21

    We introduce an extended version of oxDNA, a coarse-grained model of deoxyribonucleic acid (DNA) designed to capture the thermodynamic, structural, and mechanical properties of single- and double-stranded DNA. By including explicit major and minor grooves and by slightly modifying the coaxial stacking and backbone-backbone interactions, we improve the ability of the model to treat large (kilobase-pair) structures, such as DNA origami, which are sensitive to these geometric features. Further, we extend the model, which was previously parameterised to just one salt concentration ([Na{sup +}] = 0.5M), so that it can be used for a range of salt concentrations including those corresponding to physiological conditions. Finally, we use new experimental data to parameterise the oxDNA potential so that consecutive adenine bases stack with a different strength to consecutive thymine bases, a feature which allows a more accurate treatment of systems where the flexibility of single-stranded regions is important. We illustrate the new possibilities opened up by the updated model, oxDNA2, by presenting results from simulations of the structure of large DNA objects and by using the model to investigate some salt-dependent properties of DNA.

  10. Prediction of soil properties using imaging spectroscopy: Considering fractional vegetation cover to improve accuracy

    NASA Astrophysics Data System (ADS)

    Franceschini, M. H. D.; Demattê, J. A. M.; da Silva Terra, F.; Vicente, L. E.; Bartholomeus, H.; de Souza Filho, C. R.

    2015-06-01

    Spectroscopic techniques have become attractive to assess soil properties because they are fast, require little labor and may reduce the amount of laboratory waste produced when compared to conventional methods. Imaging spectroscopy (IS) can have further advantages compared to laboratory or field proximal spectroscopic approaches such as providing spatially continuous information with a high density. However, the accuracy of IS derived predictions decreases when the spectral mixture of soil with other targets occurs. This paper evaluates the use of spectral data obtained by an airborne hyperspectral sensor (ProSpecTIR-VS - Aisa dual sensor) for prediction of physical and chemical properties of Brazilian highly weathered soils (i.e., Oxisols). A methodology to assess the soil spectral mixture is adapted and a progressive spectral dataset selection procedure, based on bare soil fractional cover, is proposed and tested. Satisfactory performances are obtained specially for the quantification of clay, sand and CEC using airborne sensor data (R2 of 0.77, 0.79 and 0.54; RPD of 2.14, 2.22 and 1.50, respectively), after spectral data selection is performed; although results obtained for laboratory data are more accurate (R2 of 0.92, 0.85 and 0.75; RPD of 3.52, 2.62 and 2.04, for clay, sand and CEC, respectively). Most importantly, predictions based on airborne-derived spectra for which the bare soil fractional cover is not taken into account show considerable lower accuracy, for example for clay, sand and CEC (RPD of 1.52, 1.64 and 1.16, respectively). Therefore, hyperspectral remotely sensed data can be used to predict topsoil properties of highly weathered soils, although spectral mixture of bare soil with vegetation must be considered in order to achieve an improved prediction accuracy.

  11. Mapping Soil Properties of Africa at 250 m Resolution: Random Forests Significantly Improve Current Predictions.

    PubMed

    Hengl, Tomislav; Heuvelink, Gerard B M; Kempen, Bas; Leenaars, Johan G B; Walsh, Markus G; Shepherd, Keith D; Sila, Andrew; MacMillan, Robert A; Mendes de Jesus, Jorge; Tamene, Lulseged; Tondoh, Jérôme E

    2015-01-01

    80% of arable land in Africa has low soil fertility and suffers from physical soil problems. Additionally, significant amounts of nutrients are lost every year due to unsustainable soil management practices. This is partially the result of insufficient use of soil management knowledge. To help bridge the soil information gap in Africa, the Africa Soil Information Service (AfSIS) project was established in 2008. Over the period 2008-2014, the AfSIS project compiled two point data sets: the Africa Soil Profiles (legacy) database and the AfSIS Sentinel Site database. These data sets contain over 28 thousand sampling locations and represent the most comprehensive soil sample data sets of the African continent to date. Utilizing these point data sets in combination with a large number of covariates, we have generated a series of spatial predictions of soil properties relevant to the agricultural management--organic carbon, pH, sand, silt and clay fractions, bulk density, cation-exchange capacity, total nitrogen, exchangeable acidity, Al content and exchangeable bases (Ca, K, Mg, Na). We specifically investigate differences between two predictive approaches: random forests and linear regression. Results of 5-fold cross-validation demonstrate that the random forests algorithm consistently outperforms the linear regression algorithm, with average decreases of 15-75% in Root Mean Squared Error (RMSE) across soil properties and depths. Fitting and running random forests models takes an order of magnitude more time and the modelling success is sensitive to artifacts in the input data, but as long as quality-controlled point data are provided, an increase in soil mapping accuracy can be expected. Results also indicate that globally predicted soil classes (USDA Soil Taxonomy, especially Alfisols and Mollisols) help improve continental scale soil property mapping, and are among the most important predictors. This indicates a promising potential for transferring pedological

  12. Mapping Soil Properties of Africa at 250 m Resolution: Random Forests Significantly Improve Current Predictions.

    PubMed

    Hengl, Tomislav; Heuvelink, Gerard B M; Kempen, Bas; Leenaars, Johan G B; Walsh, Markus G; Shepherd, Keith D; Sila, Andrew; MacMillan, Robert A; Mendes de Jesus, Jorge; Tamene, Lulseged; Tondoh, Jérôme E

    2015-01-01

    80% of arable land in Africa has low soil fertility and suffers from physical soil problems. Additionally, significant amounts of nutrients are lost every year due to unsustainable soil management practices. This is partially the result of insufficient use of soil management knowledge. To help bridge the soil information gap in Africa, the Africa Soil Information Service (AfSIS) project was established in 2008. Over the period 2008-2014, the AfSIS project compiled two point data sets: the Africa Soil Profiles (legacy) database and the AfSIS Sentinel Site database. These data sets contain over 28 thousand sampling locations and represent the most comprehensive soil sample data sets of the African continent to date. Utilizing these point data sets in combination with a large number of covariates, we have generated a series of spatial predictions of soil properties relevant to the agricultural management--organic carbon, pH, sand, silt and clay fractions, bulk density, cation-exchange capacity, total nitrogen, exchangeable acidity, Al content and exchangeable bases (Ca, K, Mg, Na). We specifically investigate differences between two predictive approaches: random forests and linear regression. Results of 5-fold cross-validation demonstrate that the random forests algorithm consistently outperforms the linear regression algorithm, with average decreases of 15-75% in Root Mean Squared Error (RMSE) across soil properties and depths. Fitting and running random forests models takes an order of magnitude more time and the modelling success is sensitive to artifacts in the input data, but as long as quality-controlled point data are provided, an increase in soil mapping accuracy can be expected. Results also indicate that globally predicted soil classes (USDA Soil Taxonomy, especially Alfisols and Mollisols) help improve continental scale soil property mapping, and are among the most important predictors. This indicates a promising potential for transferring pedological

  13. Mapping Soil Properties of Africa at 250 m Resolution: Random Forests Significantly Improve Current Predictions

    PubMed Central

    Hengl, Tomislav; Heuvelink, Gerard B. M.; Kempen, Bas; Leenaars, Johan G. B.; Walsh, Markus G.; Shepherd, Keith D.; Sila, Andrew; MacMillan, Robert A.; Mendes de Jesus, Jorge; Tamene, Lulseged; Tondoh, Jérôme E.

    2015-01-01

    80% of arable land in Africa has low soil fertility and suffers from physical soil problems. Additionally, significant amounts of nutrients are lost every year due to unsustainable soil management practices. This is partially the result of insufficient use of soil management knowledge. To help bridge the soil information gap in Africa, the Africa Soil Information Service (AfSIS) project was established in 2008. Over the period 2008–2014, the AfSIS project compiled two point data sets: the Africa Soil Profiles (legacy) database and the AfSIS Sentinel Site database. These data sets contain over 28 thousand sampling locations and represent the most comprehensive soil sample data sets of the African continent to date. Utilizing these point data sets in combination with a large number of covariates, we have generated a series of spatial predictions of soil properties relevant to the agricultural management—organic carbon, pH, sand, silt and clay fractions, bulk density, cation-exchange capacity, total nitrogen, exchangeable acidity, Al content and exchangeable bases (Ca, K, Mg, Na). We specifically investigate differences between two predictive approaches: random forests and linear regression. Results of 5-fold cross-validation demonstrate that the random forests algorithm consistently outperforms the linear regression algorithm, with average decreases of 15–75% in Root Mean Squared Error (RMSE) across soil properties and depths. Fitting and running random forests models takes an order of magnitude more time and the modelling success is sensitive to artifacts in the input data, but as long as quality-controlled point data are provided, an increase in soil mapping accuracy can be expected. Results also indicate that globally predicted soil classes (USDA Soil Taxonomy, especially Alfisols and Mollisols) help improve continental scale soil property mapping, and are among the most important predictors. This indicates a promising potential for transferring pedological

  14. Patrick Couvreur: inspiring pharmaceutical innovation.

    PubMed

    Stanwix, Hannah

    2014-05-01

    Patrick Couvreur speaks to Hannah Stanwix, Managing Comissioning Editor: Professor Patrick Couvreur received his pharmacy degree from the Université Catholique de Louvain (Louvain-la-Neuve, Belgium) in 1972. He holds a PhD in pharmaceutical technology from the same university and completed a postdoctoral fellowship at the Eidgenössische Technische Hochschule (Zürich, Switzerland). Since 1984, Professor Couvreur has been Full Professor of Pharmacy at the Paris-Sud University (Paris, France) and was holder of the Chair of Innovation Technologique at the prestigious Collège de France (Paris, France). He has published more than 450 peer-reviewed articles and has an H-index of 73, with over 19,000 citations. Professor Coureur has been recognized by numerous national and international awards, including the 2004 Pharmaceutical Sciences World Congress Award, the prestigious Host Madsen Medal, the Prix Galien, the European Pharmaceutical Scientist Award 2011 from the European Federation of Pharmaceutical Sciences, the Médaille de l'Innovation from the Centre National de la Recherche Scientifique, and recently the European Inventor Award 2013 from the European Patent Office.

  15. Career pathways in research: pharmaceutical.

    PubMed

    Kenkre, J E; Foxcroft, D R

    The pharmaceutical pathway is the final article in this series on career pathways and highlights opportunities for nurses within associated industries. This pathway shows that nurses can use their nursing qualifications, combined with their knowledge, skills and expertise, to develop a career within another sphere of employment.

  16. Pharmaceutical crystallization with nanocellulose organogels.

    PubMed

    Ruiz-Palomero, Celia; Kennedy, Stuart R; Soriano, M Laura; Jones, Christopher D; Valcárcel, Miguel; Steed, Jonathan W

    2016-06-14

    Carboxylated nanocellulose forms organogels at 0.3 wt% in the presence of a cationic surfactant. The resulting gels can be used as novel crystallization media for pharmaceutical solid form control, resulting in isolation a new sulfapyridine solvate, morphology modification and crystallization of an octadecylammonium salt of sulfamethoxazole. PMID:27168091

  17. Comprehension by older people of medication information with or without supplementary pharmaceutical pictograms.

    PubMed

    Ng, Annie W Y; Chan, Alan H S; Ho, Vincy W S

    2017-01-01

    This study examined the benefits of pharmaceutical pictograms for improving comprehension of medication information for older people. Fifty Hong Kong Chinese older people completed a medical information comprehension task for five drugs. Participants in the control group were presented with text labels while those in the experimental group were given the text labels plus supplementary pharmaceutical pictograms, and then all reported their understanding of the medication information conveyed. Lower educated older people had poorer understanding of medication information. The addition of pharmaceutical pictograms significantly improved the comprehension of medication information for older people. The majority of older people tested with pictograms favored adding pictograms to text and thought the pictograms were useful for conveying medical information rather than using written text alone. The findings suggested that pharmaceutical and health care professionals should include pharmaceutical pictograms on labels to better convey instructions on medication to older people.

  18. Comprehension by older people of medication information with or without supplementary pharmaceutical pictograms.

    PubMed

    Ng, Annie W Y; Chan, Alan H S; Ho, Vincy W S

    2017-01-01

    This study examined the benefits of pharmaceutical pictograms for improving comprehension of medication information for older people. Fifty Hong Kong Chinese older people completed a medical information comprehension task for five drugs. Participants in the control group were presented with text labels while those in the experimental group were given the text labels plus supplementary pharmaceutical pictograms, and then all reported their understanding of the medication information conveyed. Lower educated older people had poorer understanding of medication information. The addition of pharmaceutical pictograms significantly improved the comprehension of medication information for older people. The majority of older people tested with pictograms favored adding pictograms to text and thought the pictograms were useful for conveying medical information rather than using written text alone. The findings suggested that pharmaceutical and health care professionals should include pharmaceutical pictograms on labels to better convey instructions on medication to older people. PMID:27633210

  19. The supply of pharmaceuticals in humanitarian assistance missions: implications for military operations.

    PubMed

    Mahmood, Maysaa; Riley, Kevin; Bennett, David; Anderson, Warner

    2011-08-01

    In this article, we provide an overview of key international guidelines governing the supply of pharmaceuticals during disasters and complex emergencies. We review the World Health Organization's guidelines on pharmaceutical supply chain management and highlight their relevance for military humanitarian assistance missions. Given the important role of pharmaceuticals in addressing population health needs during humanitarian emergencies, a good understanding of how pharmaceuticals are supplied at the local level in different countries can help military health personnel identify the most appropriate supply options. Familiarity with international guidelines involved in cross-border movement of pharmaceuticals can improve the ability of military personnel to communicate more effectively with other actors involved in humanitarian and development spheres. Enhancing the knowledge base available to military personnel in terms of existing supply models and funding procedures can improve the effectiveness of humanitarian military operations and invite policy changes necessary to establish more flexible acquisition and funding regulations.

  20. A consideration of the patentability of enantiomers in the pharmaceutical industry in the United States.

    PubMed

    Miller, Chris P; Ullrich, John W

    2008-06-01

    During the last thirty years, concern over stereoselectivity of drug action has drawn a great deal of interest within the pharmaceutical field due to an improved understanding of the pharmacology and pharmacokinetics of enantiomers. Developing single enantiomers versus racemates or introducing a single enantiomer following the development of the racemic mixture appears to be the new trend. The intellectual property status of single enantiomers from racemates may be unclear. Drug discoverers and patent attorneys must examine the examples of the past to establish an appropriate pathway towards the development and intellectual property protection of chiral drugs. The review will focus on the patenting of an enantiomer in view of the prior art disclosure for the racemic mixture.

  1. Stability of Chitosan—A Challenge for Pharmaceutical and Biomedical Applications

    PubMed Central

    Szymańska, Emilia; Winnicka, Katarzyna

    2015-01-01

    Chitosan—one of the natural multifunctional polymers—due to its unique and versatile biological properties is regarded as a useful compound in medical and pharmaceutical technology. Recently, considerable research effort has been made in order to develop safe and efficient chitosan products. However, the problem of poor stability of chitosan-based systems restricts its practical applicability; thus, it has become a great challenge to establish sufficient shelf-life for chitosan formulations. Improved stability can be assessed by controlling the environmental factors, manipulating processing conditions (e.g., temperature), introducing a proper stabilizing compound, developing chitosan blends with another polymer, or modifying the chitosan structure using chemical or ionic agents. This review covers the influence of internal, environmental, and processing factors on the long-term stability of chitosan products. The aim of this paper is also to highlight the latest developments which enable the physicochemical properties of chitosan-based applications to be preserved upon storage. PMID:25837983

  2. Mannitol/l-Arginine-Based Formulation Systems for Freeze Drying of Protein Pharmaceuticals: Effect of the l-Arginine Counter Ion and Formulation Composition on the Formulation Properties and the Physical State of Mannitol.

    PubMed

    Stärtzel, Peter; Gieseler, Henning; Gieseler, Margit; Abdul-Fattah, Ahmad M; Adler, Michael; Mahler, Hanns-Christian; Goldbach, Pierre

    2016-10-01

    Previous studies have shown that protein storage stability in freeze-dried l-arginine-based systems improved in the presence of chloride ions. However, chloride ions reduced the glass transition temperature of the freeze concentrate (Tg') and made freeze drying more challenging. In this study, l-arginine was freeze dried with mannitol to obtain partially crystalline solids that can be freeze dried in a fast process and result in elegant cakes. We characterized the effect of different l-arginine counter ions on physicochemical properties of mannitol compared with mannitol/sucrose systems. Thermal properties of formulations with different compositions were correlated to thermal history during freeze drying and to physicochemical properties (cake appearance, residual moisture, reconstitution time, crystallinity). Partially crystalline solids were obtained even at the highest l-arginine level (mannitol:l-arginine of 2:1) used in this study. All l-arginine-containing formulations yielded elegant cakes. Only cakes containing l-arginine chloride and succinate showed a surface "crust" formed by phase separation. X-ray powder diffraction showed that inhibition of mannitol crystallization was stronger for l-arginine compared with sucrose and varied with the type of l-arginine counter ion. The counter ion affected mannitol polymorphism and higher levels of mannitol hemi-hydrate were obtained at high levels of l-arginine chloride.

  3. Mannitol/l-Arginine-Based Formulation Systems for Freeze Drying of Protein Pharmaceuticals: Effect of the l-Arginine Counter Ion and Formulation Composition on the Formulation Properties and the Physical State of Mannitol.

    PubMed

    Stärtzel, Peter; Gieseler, Henning; Gieseler, Margit; Abdul-Fattah, Ahmad M; Adler, Michael; Mahler, Hanns-Christian; Goldbach, Pierre

    2016-10-01

    Previous studies have shown that protein storage stability in freeze-dried l-arginine-based systems improved in the presence of chloride ions. However, chloride ions reduced the glass transition temperature of the freeze concentrate (Tg') and made freeze drying more challenging. In this study, l-arginine was freeze dried with mannitol to obtain partially crystalline solids that can be freeze dried in a fast process and result in elegant cakes. We characterized the effect of different l-arginine counter ions on physicochemical properties of mannitol compared with mannitol/sucrose systems. Thermal properties of formulations with different compositions were correlated to thermal history during freeze drying and to physicochemical properties (cake appearance, residual moisture, reconstitution time, crystallinity). Partially crystalline solids were obtained even at the highest l-arginine level (mannitol:l-arginine of 2:1) used in this study. All l-arginine-containing formulations yielded elegant cakes. Only cakes containing l-arginine chloride and succinate showed a surface "crust" formed by phase separation. X-ray powder diffraction showed that inhibition of mannitol crystallization was stronger for l-arginine compared with sucrose and varied with the type of l-arginine counter ion. The counter ion affected mannitol polymorphism and higher levels of mannitol hemi-hydrate were obtained at high levels of l-arginine chloride. PMID:27506270

  4. Unhealthy marketing of pharmaceutical products: An international public health concern.

    PubMed

    Mulinari, Shai

    2016-05-01

    I consider the current state of pharmaceutical marketing vis-à-vis ethical and legal standards and advocate measures to improve it. There is abundant evidence of unethical or illicit marketing. It fuels growing concerns about undue corporate influence over pharmaceutical research, education, and consumption. The most extensive evidence of industry transgressions comes from the United States (US), where whistle-blowers are encouraged by financial rewards to help uncover illicit marketing and fraud. Outside the US increasing evidence of transgressions exists. Recently I have observed a range of new measures to align pharmaceutical marketing practices with ethical and legal standards. In the interest of public health, I highlight the need for additional and more profound reforms to ensure that information about medicines supports quality and resource-efficient care.

  5. Pharmaceutical cocrystals: the coming wave of new drug substances.

    PubMed

    Brittain, Harry G

    2013-02-01

    Solid crystalline phases containing two cocrystallized components offer a new development pathway whereby one can potentially improve the physical characteristics (i.e., equilibrium solubility, dissolution rate, solid-state stability, etc.) of a drug substance that exhibits a profile that is less than desirable. In this commentary, the topic of pharmaceutical cocrystals will be briefly explored, and a short exposition of the solubility and dissolution rate advantages that have been realized in various systems will be provided. The Guidance for Industry document recently proposed by United States Food and Drug Administration will be outlined, and its requirements explained. Finally, the subset of pharmaceutical cocrystals that consist of a drug substance and a salt of that substance (termed a salt cocrystal) will be examined to illustrate this additional class of pharmaceutical cocrystals that may offer significant scientific and regulatory advantages.

  6. Unhealthy marketing of pharmaceutical products: An international public health concern.

    PubMed

    Mulinari, Shai

    2016-05-01

    I consider the current state of pharmaceutical marketing vis-à-vis ethical and legal standards and advocate measures to improve it. There is abundant evidence of unethical or illicit marketing. It fuels growing concerns about undue corporate influence over pharmaceutical research, education, and consumption. The most extensive evidence of industry transgressions comes from the United States (US), where whistle-blowers are encouraged by financial rewards to help uncover illicit marketing and fraud. Outside the US increasing evidence of transgressions exists. Recently I have observed a range of new measures to align pharmaceutical marketing practices with ethical and legal standards. In the interest of public health, I highlight the need for additional and more profound reforms to ensure that information about medicines supports quality and resource-efficient care. PMID:26911654

  7. Efficient chemo-enzymatic gluten detoxification: reducing toxic epitopes for celiac patients improving functional properties.

    PubMed

    Ribeiro, Miguel; Nunes, Fernando M; Guedes, Sofia; Domingues, Pedro; Silva, Amélia M; Carrillo, Jose Maria; Rodriguez-Quijano, Marta; Branlard, Gérard; Igrejas, Gilberto

    2015-12-22

    Protein engineering of gluten, the exogenous effector in celiac disease, seeking its detoxification by selective chemical modification of toxic epitopes is a very attractive strategy and promising technology when compared to pharmacological treatment or genetic engineering of wheat. Here we present a simple and efficient chemo-enzymatic methodology that decreases celiac disease toxic epitopes of gluten proteins improving its technological value through microbial transglutaminase-mediated transamidation of glutamine with n-butylamine under reducing conditions. First, we found that using low concentrations of amine-nucleophile under non-reducing conditions, the decrease in toxic epitopes is mainly due to transglutaminase-mediated cross-linking. Second, using high amine nucleophile concentrations protein cross-linking is substantially reduced. Third, reducing conditions increase 7-fold the transamidation reaction further decreasing toxic epitopes amount. Fourth, using n-butylamine improves gluten hydrophobicity that strengthens the gluten network. These results open the possibility of tailoring gluten for producing hypoallergenic flours while still taking advantage of the unique viscoelastic properties of gluten.

  8. Subcritical Water Induced Complexation of Soy Protein and Rutin: Improved Interfacial Properties and Emulsion Stability.

    PubMed

    Chen, Xiao-Wei; Wang, Jin-Mei; Yang, Xiao-Quan; Qi, Jun-Ru; Hou, Jun-Jie

    2016-09-01

    Rutin is a common dietary flavonoid with important antioxidant and pharmacological activities. However, its application in the food industry is limited mainly because of its poor water solubility. The subcritical water (SW) treatment provides an efficient technique to solubilize and achieve the enrichment of rutin in soy protein isolate (SPI) by inducing their complexation. The physicochemical, interfacial, and emulsifying properties of the complex were investigated and compared to the mixtures. SW treatment had much enhanced rutin-combined capacity of SPI than that of conventional method, ascribing to the well-contacted for higher water solubility of rutin with stronger collision-induced hydrophobic interactions. Compared to the mixtures of rutin with proteins, the complex exhibited an excellent surface activity and improved the physical and oxidative stability of its stabilized emulsions. This improving effect could be attributed to the targeted accumulation of rutin at the oil-water interface accompanied by the adsorption of SPI resulting in the thicker interfacial layer, as evidenced by higher interfacial protein and rutin concentrations. This study provides a novel strategy for the design and enrichment of nanovehicle providing water-insoluble hydrophobic polyphenols for interfacial delivery in food emulsified systems.

  9. Improvement of superconducting properties of (Bi, Pb)-2223phase by TlF3 doping

    NASA Astrophysics Data System (ADS)

    Saoudel, A.; Amira, A.; Mahamdioua, N.; Boudjadja, Y.; Varilci, A.; Altintas, S. P.; Terzioglu, C.

    2016-11-01

    In this work, the superconducting properties of thallium fluoride (TlF3)doped Bi1.8-xTlxPb0.35Sr2Ca2Cu3OyF3x(x=0-0.15)compounds are presented. The X-ray diffraction analysis shows that the proportion of (Bi, Pb)-2223phase is higher than the secondary (Bi, Pb)-2212one in all samples and its highest value is about 82.74%for x=0.05. From the resistivity curves, the highest values of the onset critical transition temperature (Tc.on), the offset critical transition temperature (Tc.off) are seen for x=0.10. The calculation of activation energy (U0) in the TAFF (thermally activation flux flow) region proves the positive effect of TlF3 doping on the dissipative behavior of energy near Tc.off. Flux pinning strength is enhanced by increasing TlF3content up to x=0.10, and decreased by the application of a magnetic field. The other superconducting parameters like T(Hc2), T(Hirr), ξ(0) and μ0Hc2(0) are also improved significantly by doping. The obtained results of Ac susceptibility measurements show that the onset temperature of diamagnetism is improved by TlF3 doping, in accordance with the resistivity results.

  10. Improvement of Functional Properties of Wheat Gluten Using Acid Protease from Aspergillus usamii.

    PubMed

    Deng, Lingli; Wang, Zhaoxia; Yang, Sheng; Song, Junmei; Que, Fei; Zhang, Hui; Feng, Fengqin

    2016-01-01

    Hydrolysis parameters (temperature, E/S ratio, pH, and time) for acid protease (from Aspergillus usamii) hydrolysis of wheat gluten were optimized by response surface methodology (RSM) using emulsifying activity index (EAI) as the response factor. A temperature of 48.9°C, E/S ratio of 1.60%, pH 3.0, hydrolysis time of 2.5 h was found to be the optimum condition to obtain wheat gluten hydrolysate with higher EAI. The solubility of wheat gluten was greatly improved by hydrolysis and became independent of pH over the studied range. Enzymatic hydrolysis resulted in dramatically increase in EAI, water and oil holding capacity. Molecular weight distribution results showed that most of the peptides above 10 kDa have been hydrolyzed into smaller peptides. The results of FTIR spectra and disulfide bond (SS) and sulfhydryl (SH) content suggested that a more extensional conformation was formed after hydrolysis, which could account for the improved functional properties. PMID:27467884

  11. Efficient chemo-enzymatic gluten detoxification: reducing toxic epitopes for celiac patients improving functional properties

    PubMed Central

    Ribeiro, Miguel; Nunes, Fernando M.; Guedes, Sofia; Domingues, Pedro; Silva, Amélia M.; Carrillo, Jose Maria; Rodriguez-Quijano, Marta; Branlard, Gérard; Igrejas, Gilberto

    2015-01-01

    Protein engineering of gluten, the exogenous effector in celiac disease, seeking its detoxification by selective chemical modification of toxic epitopes is a very attractive strategy and promising technology when compared to pharmacological treatment or genetic engineering of wheat. Here we present a simple and efficient chemo-enzymatic methodology that decreases celiac disease toxic epitopes of gluten proteins improving its technological value through microbial transglutaminase-mediated transamidation of glutamine with n-butylamine under reducing conditions. First, we found that using low concentrations of amine-nucleophile under non-reducing conditions, the decrease in toxic epitopes is mainly due to transglutaminase-mediated cross-linking. Second, using high amine nucleophile concentrations protein cross-linking is substantially reduced. Third, reducing conditions increase 7-fold the transamidation reaction further decreasing toxic epitopes amount. Fourth, using n-butylamine improves gluten hydrophobicity that strengthens the gluten network. These results open the possibility of tailoring gluten for producing hypoallergenic flours while still taking advantage of the unique viscoelastic properties of gluten. PMID:26691232

  12. Graphite-nanoplatelet-decorated polymer nanofiber with improved thermal, electrical, and mechanical properties.

    PubMed

    Gao, Jiefeng; Hu, Mingjun; Dong, Yucheng; Li, Robert K Y

    2013-08-28

    Graphite-nanoplatelet (GNP)-decorated polymer nanofiber composites with hierarchical structures were fabricated by the combination of electrospinning and ultrasonication. It was found that GNPs could be well attached or embedded onto the nanofibers when their size was comparable to the nanofiber diameter. X-ray diffraction results indicated that ultrasonic treatment exerted no influence on the carbon crystal layer spacing. Fourier transform infrared spectra and Raman spectroscopy revealed the existence of interfacial interaction between GNPs and polyurethane nanofibers. The prepared nanofiber composite showed enhanced thermal stability and hardness, which originated from uniform dispersion of GNPs as well as strong interaction between GNPs and the nanofibers. The electrical conductivity was significantly improved, derived from the formation of a conductive percolation network in the nanofiber composite. During ultrasonication, cavitation bubbles may be formed in liquid, and microjets and shock waves were created near the GNP surface after collapse of the bubbles. These jets, causing sintering of GNPs, pushed GNPs toward the nanofiber surface at very high speeds. When the fast-moving GNPs hit the nanofiber surface, interfacial collision between GNPs and the nanofibers occurs, the nanofiber may experience partial softening or even melting at the impact sites, and then GNPs could be uniformly anchored onto the nanofibers. This method opens a new door for harvesting GNP-based nanofiber composites with improved material properties. PMID:23910565

  13. Improved hole-transporting property via HAT-CN for perovskite solar cells without lithium salts.

    PubMed

    Ma, Yingzhuang; Chung, Yao-Hsien; Zheng, Lingling; Zhang, Danfei; Yu, Xiao; Xiao, Lixin; Chen, Zhijian; Wang, Shufeng; Qu, Bo; Gong, Qihuang; Zou, Dechun

    2015-04-01

    A nonadditive hole-transporting material (HTM) of a triphenylamine derivative of N,N'-di(3-methylphenyl)-N,N'-diphenyl-4,4'-diaminobiphenyl (TPD) is used for the organic-inorganic hybrid perovskite solar cells. The power conversion efficiency (PCE) can be significantly enhanced by inserting a thin layer of 1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile (HAT-CN) without adding an ion additive because the hole-transporting properties improve. The short-circuit current density (J(sc)) increases from 8.5 to 13.1 mA/cm(2), the open-circuit voltage (V(oc)) increases from 0.84 to 0.92 V, and the fill-factor (FF) increases from 0.45 to 0.59, which corresponds to the increase in PCE from 3.2% to 7.1%. Moreover, the PCE decreases by only 10% after approximately 1000 h without encapsulation, which suggests an alternative method to improve the stability of perovskite solar cells. PMID:25761404

  14. Improvement of Functional Properties of Wheat Gluten Using Acid Protease from Aspergillus usamii

    PubMed Central

    Deng, Lingli; Wang, Zhaoxia; Yang, Sheng; Song, Junmei; Que, Fei; Zhang, Hui; Feng, Fengqin

    2016-01-01

    Hydrolysis parameters (temperature, E/S ratio, pH, and time) for acid protease (from Aspergillus usamii) hydrolysis of wheat gluten were optimized by response surface methodology (RSM) using emulsifying activity index (EAI) as the response factor. A temperature of 48.9°C, E/S ratio of 1.60%, pH 3.0, hydrolysis time of 2.5 h was found to be the optimum condition to obtain wheat gluten hydrolysate with higher EAI. The solubility of wheat gluten was greatly improved by hydrolysis and became independent of pH over the studied range. Enzymatic hydrolysis resulted in dramatically increase in EAI, water and oil holding capacity. Molecular weight distribution results showed that most of the peptides above 10 kDa have been hydrolyzed into smaller peptides. The results of FTIR spectra and disulfide bond (SS) and sulfhydryl (SH) content suggested that a more extensional conformation was formed after hydrolysis, which could account for the improved functional properties. PMID:27467884

  15. Subcritical Water Induced Complexation of Soy Protein and Rutin: Improved Interfacial Properties and Emulsion Stability.

    PubMed

    Chen, Xiao-Wei; Wang, Jin-Mei; Yang, Xiao-Quan; Qi, Jun-Ru; Hou, Jun-Jie

    2016-09-01

    Rutin is a common dietary flavonoid with important antioxidant and pharmacological activities. However, its application in the food industry is limited mainly because of its poor water solubility. The subcritical water (SW) treatment provides an efficient technique to solubilize and achieve the enrichment of rutin in soy protein isolate (SPI) by inducing their complexation. The physicochemical, interfacial, and emulsifying properties of the complex were investigated and compared to the mixtures. SW treatment had much enhanced rutin-combined capacity of SPI than that of conventional method, ascribing to the well-contacted for higher water solubility of rutin with stronger collision-induced hydrophobic interactions. Compared to the mixtures of rutin with proteins, the complex exhibited an excellent surface activity and improved the physical and oxidative stability of its stabilized emulsions. This improving effect could be attributed to the targeted accumulation of rutin at the oil-water interface accompanied by the adsorption of SPI resulting in the thicker interfacial layer, as evidenced by higher interfacial protein and rutin concentrations. This study provides a novel strategy for the design and enrichment of nanovehicle providing water-insoluble hydrophobic polyphenols for interfacial delivery in food emulsified systems. PMID:27467966

  16. Improving the coherence properties of solid-state spin ensembles via optimized dynamical decoupling

    NASA Astrophysics Data System (ADS)

    Farfurnik, D.; Jarmola, A.; Pham, L. M.; Wang, Z. H.; Dobrovitski, V. V.; Walsworth, R. L.; Budker, D.; Bar-Gill, N.

    2016-04-01

    In this work, we optimize a dynamical decoupling (DD) protocol to improve the spin coherence properties of a dense ensemble of nitrogen-vacancy (NV) centers in diamond. Using liquid nitrogen-based cooling and DD microwave pulses, we increase the transverse coherence time T2 from ˜ 0.7 ms up to ˜ 30 ms. We extend previous work of single-axis (Carr-Purcell-Meiboom-Gill) DD towards the preservation of arbitrary spin states. After performing a detailed analysis of pulse and detuning errors, we compare the performance of various DD protocols. We identify that the concatenated XY8 pulse sequences serves as the optimal control scheme for preserving an arbitrary spin state. Finally, we use the concatenated sequences to demonstrate an immediate improvement of the AC magnetic sensitivity up to a factor of two at 250 kHz. For future work, similar protocols may be used to increase coherence times up to NV-NV interaction time scales, a major step toward the creation of quantum collective NV spin states.

  17. High-pressure studies of pharmaceutical compounds and energetic materials.

    PubMed

    Fabbiani, Francesca P A; Pulham, Colin R

    2006-10-01

    The effects of high pressure on pharmaceutical compounds and energetic materials can have important implications for both the properties and performance of these important classes of material. Pharmaceutical compounds are frequently subjected to pressure during processing and formulation, causing interconversion between solid forms that may affect properties such as solubility and bio-availability. Energetic materials experience extremes of both pressure and temperature under conditions of detonation and deflagration, causing changes in properties such as sensitivity to shock and chemical reactivity. This tutorial review outlines the various methods used to study these materials at high pressure, describes how pressure can be used to explore polymorphism, and provides examples of compounds that have been studied at high pressure. PMID:17003899

  18. High-pressure studies of pharmaceutical compounds and energetic materials.

    PubMed

    Fabbiani, Francesca P A; Pulham, Colin R

    2006-10-01

    The effects of high pressure on pharmaceutical compounds and energetic materials can have important implications for both the properties and performance of these important classes of material. Pharmaceutical compounds are frequently subjected to pressure during processing and formulation, causing interconversion between solid forms that may affect properties such as solubility and bio-availability. Energetic materials experience extremes of both pressure and temperature under conditions of detonation and deflagration, causing changes in properties such as sensitivity to shock and chemical reactivity. This tutorial review outlines the various methods used to study these materials at high pressure, describes how pressure can be used to explore polymorphism, and provides examples of compounds that have been studied at high pressure.

  19. Preparation, physicochemical and pharmaceutical characterization of chitosan from Catharsius molossus residue.

    PubMed

    Ma, Jiahua; Xin, Chao; Tan, Chengjia

    2015-09-01

    Polypeptide from Catharsius molossus L. is an active ingredient in the treatment of benign prostatic hyperplasia. The residue after extraction is harmful to the environment and is also a waste of resources. Chitosan was extracted from C. molossus L. residue with chemical methods and with an improved intermittent heating method. Physicochemical and pharmaceutical characteristics of chitosan from C. molossus L. and shrimp were mainly measured by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM). The results showed chitosan from C. molossus L. was superior to commercial medical-grade chitosan from shrimp in the aspects of degree of deacetylation, crystallinity, heavy metal content, viscosity, protein residue, ash content, and in vitro adhesion. In addition, properties of chitosan membrane were studied, including water vapor permeability, light transmittance, enzymatic hydrolysis, swelling behavior, mechanical properties, and SEM images. It was found that the membrane of chitosan from C. molossus L. had better performance. This preliminary result shows chitosan from C. molossus L. is more suitable than shrimp's as a pharmaceutical excipient in colonic adhesive drug delivery system. PMID:26188302

  20. Tackling corruption in the pharmaceutical systems worldwide with courage and conviction.

    PubMed

    Cohen, J C; Mrazek, M; Hawkins, L

    2007-03-01

    Poor drug access continues to be one of the main global health problems. Global inequalities in access to pharmaceuticals are caused by a number of variables including poverty, high drug prices, poor health infrastructure, and fraud and corruption--the latter being the subject of this article. There is growing recognition among policy makers that corruption in the pharmaceutical system can waste valuable resources allocated to pharmaceutical products and services. This, in turn, denies those most in need from life-saving or life-enhancing medicines. As a result, international organizations, including the World Health Organization and the World Bank are beginning to address the issue of corruption in the health sector broadly and the pharmaceutical system specifically. This is encouraging news for improving drug access for the global poor who are most harmed by corruption as they tend to purchase less expensive drugs from unqualified or illegal drug sellers selling counterfeit or sub-standard drugs. In our paper, we illuminate what are the core issues that relate to corruption in the pharmaceutical sector. We argue that corruption in the pharmaceutical system can be detrimental to a country's ability to improve the health of its population. Moreover, unless policy makers deal with the issue of corruption, funding allocated to the pharmaceutical system to treat health conditions may simply be wasted and the inequality between rich and poor in access to health and pharmaceutical products will be aggravated.

  1. Evaluation of effects of pharmaceutical processing on structural disorders of active pharmaceutical ingredient crystals using nanoindentation and high-resolution total scattering pair distribution function analysis.

    PubMed

    Chen, Shuang; Sheikh, Ahmad Y; Ho, Raimundo

    2014-12-01

    Pharmaceutical unit operations such as milling and compaction can often generate disordered regions in crystals of active pharmaceutical ingredients (APIs). This may lead to changes in a number of important pharmaceutical properties including dissolution, stability, hygroscopicity, and so on. It is therefore important for pharmaceutical industry to evaluate the effects of pharmaceutical processing on API structural orders, and to investigate and develop analytical tools that are capable of accurately detecting and assessing subtle process-induced structural disorders in pharmaceutical crystals. In this study, nanoindentation was first used to determine the intrinsic mechanical properties including hardness and Young's modulus of two API crystals, compounds 1 and 2. These crystals of different mechanical properties were then milled and compacted under various conditions. The resulting structural disorders in these crystals were subsequently evaluated using synchrotron-based high-resolution total scattering pair distribution function (TS-PDF) analysis. Furthermore, principal component analysis was applied to the PDF data to assess the relative extents of disorders in the API crystals, which showed a good correlation with the process conditions. The study demonstrates that high-resolution TS-PDF analysis coupled with nanoindentation measurement is a valuable and effective tool for detecting and assessing process-induced subtle structural disorders in API crystals.

  2. Quantitative mass spectrometry methods for pharmaceutical analysis.

    PubMed

    Loos, Glenn; Van Schepdael, Ann; Cabooter, Deirdre

    2016-10-28

    Quantitative pharmaceutical analysis is nowadays frequently executed using mass spectrometry. Electrospray ionization coupled to a (hybrid) triple quadrupole mass spectrometer is generally used in combination with solid-phase extraction and liquid chromatography. Furthermore, isotopically labelled standards are often used to correct for ion suppression. The challenges in producing sensitive but reliable quantitative data depend on the instrumentation, sample preparation and hyphenated techniques. In this contribution, different approaches to enhance the ionization efficiencies using modified source geometries and improved ion guidance are provided. Furthermore, possibilities to minimize, assess and correct for matrix interferences caused by co-eluting substances are described. With the focus on pharmaceuticals in the environment and bioanalysis, different separation techniques, trends in liquid chromatography and sample preparation methods to minimize matrix effects and increase sensitivity are discussed. Although highly sensitive methods are generally aimed for to provide automated multi-residue analysis, (less sensitive) miniaturized set-ups have a great potential due to their ability for in-field usage.This article is part of the themed issue 'Quantitative mass spectrometry'.

  3. UPLC: a preeminent technique in pharmaceutical analysis.

    PubMed

    Kumar, Ashok; Saini, Gautam; Nair, Anroop; Sharma, Rishbha

    2012-01-01

    The pharmaceutical companies today are driven to create novel and more efficient tools to discover, develop, deliver and monitor the drugs. In this contest the development of rapid chromatographic method is crucial for the analytical laboratories. In precedent decade, substantial technological advances have been done in enhancing particle chemistry performance, improving detector design and in optimizing the system, data processors and various controls of chromatographic techniques. When all was blended together, it resulted in the outstanding performance via ultra-high performance liquid chromatography (UPLC), which holds back the principle of HPLC technique. UPLC shows a dramatic enhancement in speed, resolution as well as the sensitivity of analysis by using particle size less than 2 pm and the system is operational at higher pressure, while the mobile phase could be able to run at greater linear velocities as compared to HPLC. This technique is considered as a new focal point in field of liquid chromatographic studies. This review focuses on the basic principle, instrumentation of UPLC and its advantages over HPLC, furthermore, this article emphasizes various pharmaceutical applications of this technique.

  4. Pharmaceutical Applications of Ion-Exchange Resins

    NASA Astrophysics Data System (ADS)

    Elder, David P.

    2005-04-01

    The historical uses of ion-exchange resins and a summary of the basic chemical principles involved in the ion-exchange process are discussed. Specific applications of ion-exchange resins are provided. The utility of these agents to stabilize drugs are evaluated. Commonly occurring chemical and physical incompatibilities are reviewed. Ion-exchange resins have found applicability as inactive pharmaceutical constituents, particularly as disintegrants (inactive tablet ingredient whose function is to rapidly disrupt the tablet matrix on contact with gastric fluid). One of the more elegant approaches to improving palatability of ionizable drugs is the use of ion-exchange resins as taste-masking agents. The selection, optimization of drug:resin ratio and particle size, together with a review of scaleup of typical manufacturing processes for taste-masked products are provided. Ion-exchange resins have been extensively utilized in oral sustained-release products. The selection, optimization of drug:resin ratio and particle size, together with a summary of commonly occurring commercial sustained-release products are discussed. Ion-exchange resins have also been used in topical products for local application to the skin, including those where drug flux is controlled by a differential electrical current (ionotophoretic delivery). General applicability of ion-exchange resins, including ophthalmic delivery, nasal delivery, use as drugs in their own right (e.g., colestyramine, formerly referred to as cholestyramine), as well as measuring gastrointestinal transit times, are discussed. Finally, pharmaceutical monographs for ion-exchange resins are reviewed.

  5. Bias, complexity, and uncertainty in ecosystem risk assessment: pharmaceuticals, a new challenge in scale and perspective

    NASA Astrophysics Data System (ADS)

    Duffy, Lawrence K.; Dunlap, Kriya L.; Godduhn, Anna R.

    2014-09-01

    Because thousands of pharmaceutical and industrial compounds are in use today and distributed into ecosystems via waste water, effective analysis of environmental risk needs to change as our understanding of the complexity of ecosystem services grows. Klaminder et al (2014 Environ. Res. Lett. 9 084003) now provide some important observations on a methodological bias in standardized ecotoxicological tests. First, the authors show that the formalized use of control species in risk assessment impacts how data is judged and valued. Reducing quantitative uncertainty may improve the rigor of toxicological assays, but may also increase the risk of missing likely ecosystem-scale impacts, essentially ‘throwing the baby out with the bathwater’. Second, we should recognize the importance of integrating nature, complexity, and dynamics across temporal and spatial scales in relation to the unintended consequences of pharmaceuticals and their partial degradation products in the environment. Since ecosystems and our broader life support system are composed of various stability states with dynamic cycles, feedback can destabilize a system as we know it. Complex systems have emergent properties with high degrees of uncertainty and ecosystem risk assessments must report not only toxicological risks but also ‘benefits’. In addition, risk assessment must expand its scale from the molecular and cellular to that of the ecosystem with real world conditions. The authors’ findings that exposure to Oxazepam led to increased survival and aggressiveness should inform changes in standardized testing methodology as well as improvements in regulatory policy.

  6. Zwitterionic polymer functionalization of polysulfone membrane with improved antifouling property and blood compatibility by combination of ATRP and click chemistry.

    PubMed

    Xiang, Tao; Lu, Ting; Xie, Yi; Zhao, Wei-Feng; Sun, Shu-Dong; Zhao, Chang-Sheng

    2016-08-01

    The chemical compositions are very important for designing blood-contacting membranes with good antifouling property and blood compatibility. In this study, we propose a method combining ATRP and click chemistry to introduce zwitterionic polymer of poly(sulfobetaine methacrylate) (PSBMA), negatively charged polymers of poly(sodium methacrylate) (PNaMAA) and/or poly(sodium p-styrene sulfonate) (PNaSS), to improve the antifouling property and blood compatibility of polysulfone (PSf) membranes. Attenuated total reflectance-Fourier transform infrared spectra, X-ray photoelectron spectroscopy and water contact angle results confirmed the successful grafting of the functional polymers. The antifouling property and blood compatibility of the modified membranes were systematically investigated. The zwitterionic polymer (PSBMA) grafted membranes showed good resistance to protein adsorption and bacterial adhesion; the negatively charged polymer (PNaSS or PNaMAA) grafted membranes showed improved blood compatibility, especially the anticoagulant property. Moreover, the PSBMA/PNaMAA modified membrane showed both antifouling property and anticoagulant property, and exhibited a synergistic effect in inhibiting blood coagulation. The functionalization of membrane surfaces by a combination of ATRP and click chemistry is demonstrated as an effective route to improve the antifouling property and blood compatibility of membranes in blood-contact. PMID:27039977

  7. Improvement of coal water slurry property through coal physicochemical modifications by microwave irradiation and thermal heat

    SciTech Connect

    Jun Cheng; Junhu Zhou; Yanchang Li; Jianzhong Liu; Kefa Cen

    2008-07-15

    To improve the coal water slurry (CWS) property made from Chinese Shenhua coal with high inherent moisture and oxygen contents, microwave irradiation and thermal heat were employed to modify the coal physicochemical property. Microwave irradiation reduces the inherent moisture and reforms the oxygenic function groups, while it decreases the total specific surface area. Thermal heat markedly decreases the inherent moisture, volatile, and oxygen contents, while it dramatically increases the total specific surface area. Therefore, microwave irradiation gives a higher CWS concentration and a better rheological behavior than thermal heat, while it remarkably reduces the operation time and energy consumption. The maximum CWS concentration given by microwave irradiation at 420 W for 60 s is 62.14%, which is not only higher than that of 60.41% given by thermal heat at 450{sup o}C for 0.5 h but also higher than the initial 58.23%. Meanwhile, the minimum shear stress given by microwave irradiation is 36.4 Pa at the shear rate of 100 s{sup -1}, which is not only lower than that of 42.4 Pa given by thermal heat but also lower than the initial 79.8 Pa. The minimum unit energy consumption of 0.115 kWh/(kg of coal) and electricity cost of 4.6 U.S. $/(ton of coal) for CWS concentration promotion by 1% are obtained at 420 W for 20 s in the microwave oven. The unit energy consumptions for CWS concentration promotion and inherent moisture removal by thermal heat are, respectively, 214 and 22.5 times higher than those by microwave irradiation, while the energy use efficiencies are on the converse. 27 refs., 11 figs., 2 tabs.

  8. An effective approach for modifying carbonaceous materials with niobium single sites to improve their catalytic properties.

    PubMed

    Bozzi, A S; Lavall, R L; Souza, T E; Pereira, M C; de Souza, P P; De Abreu, H A; De Oliveira, A; Ortega, P F R; Paniago, R; Oliveira, L C A

    2015-12-14

    In this paper we show a very simple route for the incorporation of catalytically active niobium species on the surface of carbon materials, such as graphene oxide, carbon nanotubes and activated carbon. Some existing methods of incorporating a transition metal on a support have involved co-precipitation or wet impregnation, to obtain the corresponding oxides. These methods, however, cause reduction in the specific area of the support and can also form large metal oxide particles with loss of metal exposure. Therefore, here we present a novel way to add catalytically active species on the surfaces of different types of carbon through the formation of interaction complexes between the metal precursor and the functional groups of the carbon matrix. Because of the excellent catalytic properties exhibited by the niobium species we choose the NH4[NbO(C2O4)2(H2O)2]·2H2O salt as the model precursor. The characterization by XPS reveals the presence of the niobium species indicated by the displacement of the peaks between 206-212 eV related to the oxalate species according to the spectrum from pure niobium oxalate. Images obtained by TEM and SEM show the typical morphologies of carbonaceous materials without the niobium oxide formation signal, which indicates the presence of niobium complexes as isolated sites on the carbon surfaces. This new class of materials exhibited excellent properties as catalysts for pollutant oxidation. The presence of Nb promotes the catalytic activation of H2O2 generating hydroxyl radicals in situ, which allows their use in the organic compound oxidation processes. Tests for DBT oxidation indicate that Nb significantly improves the removal of such pollutants in biphasic reactions with removal around 90% under the tested conditions. Theoretical calculations showed that the most favorable adsorption model is an ionic complex presenting a ΔG = -108.7 kcal mol(-1) for the whole adsorption process. PMID:26514577

  9. Improved hardness and wear properties of B-ion implanted polycarbonate

    SciTech Connect

    Lee, E.H.; Rao, G.R.; Mansur, L.K. )

    1992-07-01

    Polycarbonate (Lexan) was implanted with 100 and 200 keV B{sup +} ions to doses of 0.26, 0.78, and 2.6{times}10{sup 15} ions/cm{sup 2} at room temperature ({lt}100 {degree}C). Mechanical characterization of implanted materials was carried out by nanoindentation and sliding wear tests. The results showed that the hardness of implanted polycarbonate increased with increasing ion energy and dose, attaining hardness up to 3.2 GPa at a dose of 2.6{times}10{sup 15} ions/cm{sup 2} for 200 keV ions, which is more than 10 times that of the unimplanted polymer. Wear properties were characterized using a reciprocating tribometer with nylon, brass, and SAE 52100 Cr-steel balls with 0.5 and 1 N normal forces for 10 000 cycles. The wear mode varied widely as a function of ion energy, dose, wear ball type, and normal load. For given ion energy, load, and ball type conditions, there was an optimum dose that produced the greatest wear resistance and lowest friction coefficient. For polycarbonate implanted with 0.78{times}10{sup 15} ions/cm{sup 2}, the nylon ball produced no wear after 10 000 cycles. Moreover, the overall friction coefficient was reduced by over 40% by implantation. The results suggest that the potential of ion-beam technology for improving polycarbonate is significant, and that surface-sensitive mechanical properties can be tailored to meet the requirements for applications demanding hardness, wear, and abrasion resistance.

  10. Marine Polysaccharides in Pharmaceutical Applications: An Overview

    PubMed Central

    Laurienzo, Paola

    2010-01-01

    The enormous variety of polysaccharides that can be extracted from marine plants and animal organisms or produced by marine bacteria means that the field of marine polysaccharides is constantly evolving. Recent advances in biological techniques allow high levels of polysaccharides of interest to be produced in vitro. Biotechnology is a powerful tool to obtain polysaccharides from a variety of micro-organisms, by controlling the growth conditions in a bioreactor while tailoring the production of biologically active compounds. Following an overview of the current knowledge on marine polysaccharides, with special attention to potential pharmaceutical applications and to more recent progress on the discovering of new polysaccharides with biological appealing characteristics, this review will focus on possible strategies for chemical or physical modification aimed to tailor the final properties of interest. PMID:20948899

  11. Prospects for Anti-Biofilm Pharmaceuticals

    PubMed Central

    Stewart, Philip S.

    2015-01-01

    This commentary highlights several avenues currently being pursued in research labs to the development of new anti-biofilm pharmaceuticals. There is a real need for alternative therapeutic modalities for treating the persistent infections that sometimes form on implanted medical devices or compromised niches within the body. Strategies being researched include discovering new antimicrobial agents that kill microorganisms in biofilms more effectively than do existing antibiotics, designing drugs that block microbial adhesion or interfere with intercellular communication, developing chemistries to disperse biofilms, and combining agents with different mechanisms of action. Though the need is great, the pathway to commercialization of new drugs is steep. One possible streamlined approach to navigating the regulatory approval process is to repurpose old drugs, a strategy that a few groups have shown can yield agents with anti-biofilm properties. PMID:26343685

  12. Pharmaceutical Particle Engineering via Spray Drying

    PubMed Central

    2007-01-01

    This review covers recent developments in the area of particle engineering via spray drying. The last decade has seen a shift from empirical formulation efforts to an engineering approach based on a better understanding of particle formation in the spray drying process. Microparticles with nanoscale substructures can now be designed and their functionality has contributed significantly to stability and efficacy of the particulate dosage form. The review provides concepts and a theoretical framework for particle design calculations. It reviews experimental research into parameters that influence particle formation. A classification based on dimensionless numbers is presented that can be used to estimate how excipient properties in combination with process parameters influence the morphology of the engineered particles. A wide range of pharmaceutical application examples—low density particles, composite particles, microencapsulation, and glass stabilization—is discussed, with specific emphasis on the underlying particle formation mechanisms and design concepts. PMID:18040761

  13. Improvement of barrier properties of poly(ethylene terephthalate)/organoclay nanocomposites

    NASA Astrophysics Data System (ADS)

    Dini, Maryam

    The presence of nanoclays in poly(ethylene terephthalate) (PET) as an impermeable phase and for increasing the tortuous path of permeates can result in outstanding property improvements in terms of decreasing gas permeability. PET nanocomposites can be prepared by in-situ or melt-mixing methods. The latter approach is more economical, practical and environmental friendly due to the absence of monomers and/or organic solvents. The microstructure of polymer nanocomposites substantially plays an important role in the determining macroscopic properties of final products. To achieve significant performance enhancements, good dispersion of the nanoclay in the matrix and thermodynamic compatibility between the nanoclay and the polymer are required. In this work, poly(ethylene terephthalate) (PET) nanocomposites were prepared by water-assisted melt compounding in a twin-screw extruder. In order to facilitate the diffusion of PET molecules into clay galleries, steam was fed into the extruder. Subsequently, the molecular weight (M W) reduction of the PET matrix, due to hydrolysis by water, was compensated by solid-state polymerization (SSP). Effects of feeding rate, compatibility between PET and nanoclay (Cloisite Na+, Cloisite 30B and Nanomer I.28E) and SSP on the microstructure of the nanocomposites were studied. The results revealed more delamination of organoclay platelets in PET-C30B nanocomposites processed at low feeding rate compared to those processed at high feeding rate. The presence of water resulted in a larger number of single and double layers of C30B nanoparticles as well as an increased aspect ratio of clay particles in PET nanocomposites. The effect of water on the microstructure of PET nanocomposites was strongly dependent on the nanoclay modifier. Processing with water had negative effects on the PET-I28E nanocomposites, because of its lower compatibility. Studies on the structure of PET after SSP by rheological measurements, Nuclear magnetic resonance

  14. Preparation and characterization of herbal creams for improvement of skin viscoelastic properties.

    PubMed

    Ahshawat, M S; Saraf, S; Saraf, S

    2008-06-01

    The aim of this study was to formulate and evaluate herbal cosmetic creams for their improvement of skin viscoelastic and hydration properties. The cosmetic cream formulations were designed by using ethanolic extracts of Glycyrriza glabra, Curcuma longa (roots), seeds of Psorolea corlifolia, Cassia tora, Areca catechu, Punica granatum, fruits of Embelica officinale, leaves of Centella asiatica, dried bark of Cinnamon zeylanicum and fresh gel of Aloe vera in varied concentrations (0.12-0.9%w/w) and characterized using physicochemical and physiological measurements. The ethanolic extracts of herbs were incorporated in a cream base that is prepared by a phase inversion emulsification technique. The cream base was prepared by utilizing oil of Prunus amagdalus, Sesamum indicum, honey, cetyl alcohol, stearic acid, polysorbate monoleate, sorbitan monostearate, propylene glycol and glycerin. Physicochemical assessments and microbiological testing were completed for all formulations according to the methods of the Indian Standard Bureau. The studies were carried out for 6 weeks on normal subjects (6 males and 12 females, between 22 and 50 years) on the back of their volar forearm for evaluation of viscoelastic properties in terms of extensibility via a suction measurement, firmness using laboratory fabricated instruments such as ball bouncing and skin hydration using electric (resistance) measurement methods. The physicochemical parameters of formulations CAA1-CAA6, i.e. pH, acid value, saponification value, viscosity, spreadability, layer thickness microbial count and skin sensitivity were found to be in the range of 5.01 +/- 0.4-6.07 +/- 0.6, 3.3-5.1 +/- 0.2, 20-32, 5900-6755 cps, 60-99%, 25-50 mum, 31-46 colony-forming units (CFU) and a 0-1 erythema score. The formulations, CAA4 and CAA5, showed an increase in percentage extensibility (32.27 +/- 1.7% and 29.89 +/- 1.64%, respectively), firmness (28.86 +/- 0.86% and 29.89 +/- 2.8%, respectively) and improved skin

  15. Percentage-Method Improves Properties of Workers’ Sitting- and Walking-Time Questionnaire

    PubMed Central

    Matsuo, Tomoaki; Sasai, Hiroyuki; So, Rina; Ohkawara, Kazunori

    2016-01-01

    Background Does asking for the percentage of time spent sitting during work (P-method) instead of asking for the absolute length of time spent sitting (T-method) improve properties of the workers’ sitting- and walking-time questionnaire (WSWQ)? The purpose of this study was to investigate whether questioning technique influences test-retest reliability and criterion validity of the WSWQ. Methods Sixty-five Japanese workers completed each version of the WSWQ in random order. Both questionnaires assessed quantities of time spent sitting or walking (including standing) during work time, non-working time on a workday, and anytime on a non-workday. Participants wore the thigh-worn inclinometer (activPAL) as criterion measure. Intraclass correlation coefficients (ICC) and Spearman’s ρ were used for the analyses. Results For all three domains, values of reliability and validity with the P-method tended to be higher than with the T-method: ICC values ranged from 0.48–0.85 for the T-method and from 0.71–0.85 for the P-method; Spearman’s ρ values ranged from 0.25–0.58 for the T-method and from 0.42–0.65 for the P-method. The validities with both methods on a workday (0.51–0.58 for the T-method and 0.56–0.65 for the P-method) were higher than validities on a non-workday (0.25–0.45 for the T-method and 0.42–0.60 for the P-method). In post-survey interviews, 48 participants (77%) chose the P-method as their preferred questioning style. Conclusions The study revealed that the P-method WSWQ had better reliability, validity, and ease of answering than the T-method, suggesting that the P-method can improve properties of the WSWQ and consequently advance the quality of epidemiological surveys in this field. PMID:26853102

  16. Method Developed for Improving the Thermomechanical Properties of Silicon Carbide Matrix Composites

    NASA Technical Reports Server (NTRS)

    Bhatt, Ramakrishna T.; DiCarlo, James A.

    2004-01-01

    Today, a major thrust for achieving engine components with improved thermal capability is the development of fiber-reinforced silicon-carbide (SiC) matrix composites. These materials are not only lighter and capable of higher use temperatures than state-of-the-art metallic alloys and oxide matrix composites (approx. 1100 C), but they can provide significantly better static and dynamic toughness than unreinforced silicon-based monolithic ceramics. However, for successful application in advanced engine systems, the SiC matrix composites should be able to withstand component service stresses and temperatures for the desired component lifetime. Since the high-temperature structural life of ceramic materials is typically controlled by creep-induced flaw growth, a key composite property requirement is the ability to display high creep resistance under these conditions. Also, because of the possibility of severe thermal gradients in the components, the composites should provide maximum thermal conductivity to minimize the development of thermal stresses. State-of-the-art SiC matrix composites are typically fabricated via a three-step process: (1) fabrication of a component-shaped architectural preform reinforced by high-performance fibers, (2) chemical vapor infiltration of a fiber coating material such as boron nitride (BN) into the preform, and (3) infiltration of a SiC matrix into the remaining porous areas in the preform. Generally, the highest performing composites have matrices fabricated by the CVI process, which produces a SiC matrix typically more thermally stable and denser than matrices formed by other approaches. As such, the CVI SiC matrix is able to provide better environmental protection to the coated fibers, plus provide the composite with better resistance to crack propagation. Also, the denser CVI SiC matrix should provide optimal creep resistance and thermal conductivity to the composite. However, for adequate preform infiltration, the CVI SiC matrix

  17. Root Uptake of Pharmaceuticals and Personal Care Product Ingredients.

    PubMed

    Miller, Elizabeth L; Nason, Sara L; Karthikeyan, K G; Pedersen, Joel A

    2016-01-19

    Crops irrigated with reclaimed wastewater or grown in biosolids-amended soils may take up pharmaceuticals and personal care product ingredients (PPCPs) through their roots. The uptake pathways followed by PPCPs and the propensity for these compounds to bioaccumulate in food crops are still not well understood. In this critical review, we discuss processes expected to influence root uptake of PPCPs, evaluate current literature on uptake of PPCPs, assess models for predicting plant uptake of these compounds, and provide recommendations for future research, highlighting processes warranting study that hold promise for improving mechanistic understanding of plant uptake of PPCPs. We find that many processes that are expected to influence PPCP uptake and accumulation have received little study, particularly rhizosphere interactions, in planta transformations, and physicochemical properties beyond lipophilicity (as measured by Kow). Data gaps and discrepancies in methodology and reporting have so far hindered development of models that accurately predict plant uptake of PPCPs. Topics warranting investigation in future research include the influence of rhizosphere processes on uptake, determining mechanisms of uptake and accumulation, in planta transformations, the effects of PPCPs on plants, and the development of predictive models. PMID:26619126

  18. Improved physiological properties of gravity-enforced reassembled rat and human pancreatic pseudo-islets.

    PubMed

    Zuellig, R A; Cavallari, G; Gerber, P; Tschopp, O; Spinas, G A; Moritz, W; Lehmann, R

    2014-04-16

    Previously we demonstrated the superiority of small islets vs large islets in terms of function and survival after transplantation, and we generated reaggregated rat islets (pseudo-islets) of standardized small dimensions by the hanging-drop culture method (HDCM). The aim of this study was to generate human pseudo-islets by HDCM and to evaluate and compare the physiological properties of rat and human pseudo-islets. Isolated rat and human islets were dissociated into single cells and incubated for 6-14 days by HDCM. Newly formed pseudo-islets were analysed for dimensions, morphology, glucose-stimulated insulin secretion (GSIS) and total insulin content. The morphology of reaggregated human islets was similar to that of native islets, while rat pseudo-islets had a reduced content of α and δ cells. GSIS of small rat and human pseudo-islets (250 cells) was increased up to 4.0-fold (p < 0.01) and 2.5-fold (p < 0.001), respectively, when compared to their native counterparts. Human pseudo-islets showed a more pronounced first-phase insulin secretion as compared to intact islets. GSIS was inversely correlated to islet size, and small islets (250 cells) contained up to six-fold more insulin/cell than large islets (1500 cells). Tissue loss with this new technology could be reduced to 49.2 ± 1.5% in rat islets, as compared to the starting amount. With HDCM, pseudo-islets of standardized size with similar cellular composition and improved biological function can be generated, which compensates for tissue loss during production. Transplantation of small pseudo-islets may represent an attractive strategy to improve graft survival and function, due to better oxygen and nutrient supply during the phase of revascularization. Copyright © 2014 John Wiley & Sons, Ltd.

  19. Volatile hydrocarbons in pharmaceutical solutions

    SciTech Connect

    Kroneld, R. )

    1991-07-01

    Volatile pollutants such as hydrocarbons have, during many years, been analysed in small concentrations in air, water, food, pharmaceutical solutions, and human blood and tissues. It has also been shown that such substances have unexpected consequences for cell cultures and scientific experiments. These substances also accumulate in patients receiving haemodialysis and these patients are exposed to quite high concentrations. The knowledge of the toxicity of such compounds has led to the development of maximum limit concentrations with the aim to decrease the exposure of humans. This paper discusses the problems of human exposure in general and especially through pharmaceutical solutions, and the possibilities of eliminating such compounds with the aim of decreasing the exposure as a hygienic challenge.

  20. Quality analytics of Internet pharmaceuticals.

    PubMed

    Baert, B; De Spiegeleer, B

    2010-09-01

    Trading pharmaceutical products through the Internet poses several challenges related to legal responsibilities, good distribution practices, information content and patient use, financial implications, but also regarding product quality. One of the major concerns is the well-known phenomenon of counterfeited and/or substandard drugs commercialized through rogue Internet sites. Therefore, controlling and assuring the quality of those products has become an important and challenging task for the authorities. This review gives an overview of the different quality attributes that can be evaluated to have a complete understanding of the quality of the finished pharmaceutical product traded through the Internet, as well as the current analytical techniques that serve this objective. Aspects considered are labelling and packaging, physicochemical quality attributes, identification and assay of active substances and/or excipients, impurity profiling, biopharmaceutical testing and data interpretation.