Photstabilization of Bioethanomethrin, Resmethrin, and natural Pyrethrins (Pyrethrum) by mixed Diaryl-p-phenylenediamines

Treesearch

Nancy L. Rappaport; Renè G. Pieper

1982-01-01

Natural pyrethrins and nonhalogenated synthetic pyrethroids are highly active and safe insecticides but are not photostable. A stabilized formulation was developed based on 1% of mixed diarly-p-phenylenediamines in an aromatic solvent. The synthetic pyrethroids bioethanomethrin and resmethrin as well as natural pyrethrins were protected from degradation when exposed...

Immobilization of natural anti-oxidants on carbon nanotubes and aging behavior of ultra-high molecular weight polyethylene-based nanocomposites

NASA Astrophysics Data System (ADS)

Dintcheva, Nadka Tzankova; Arrigo, Rossella; Gambarotti, Cristian; Guenzi, Monica; Carroccio, Sabrina; Cicogna, Francesca; Filippone, Giovanni

2014-05-01

The use of natural antioxidants is an attractive way to formulate nanocomposites with extended durability and with potential applications in bio-medical field. In this work, Vitamin E (VE) in the form of α-tocopherol and Quercetin (Q) are physically immobilized on the outer surface of multi-walled carbon nanotubes (CNTs). Afterward, the CNTs-VE and CNTs-Q are used to formulate thermally stable ultra high molecular weight polyethylene based nanocomposites. The obtained results in the study of the thermo-oxidation behavior suggest a beneficial effect of the natural anti-oxidant carbon nanotubes systems. The unexpected excellent thermo-resistance of the nanocomposites seems to be due to a synergistic effect of the natural anti-oxidant and carbon nanotubes, i.e. strong interaction between CNT surface and anti-oxidant molecules. Particularly, these interactions cause the formation of structural defects onto outer CNT surfaces, which, in turn, increase the CNT radical scavenging activity.

Efficacy of triclosan-based toothpastes in the prevention and treatment of plaque-induced periodontal and peri-implant diseases.

PubMed

Trombelli, L; Farina, R

2013-03-01

To evaluate the efficacy of triclosan (T)-based toothpaste formulations in the prevention and treatment of plaque-induced periodontal and peri-implant diseases. A review of the existing literature was conducted with a systematic approach in order to retrieve pertinent articles. i) Compared with a control fluoride dentifrice, a fluoride dentifrice containing T formulations provides a more effective level of plaque control and gingival health in patients affected by gingivitis; ii) 0.3% T/2% copolymer/0.243% NaF formulation and 0.3% T/0.13% Ca glicerophosphate/1000 ppm F toothpaste in a natural Ca carbonate base seem the most effective T-based toothpaste formulations in controlling plaque and gingival inflammation in patients with gingivitis or mild/moderate periodontitis over a 6-month period; iii) 0.3% T/2% copolymer/0.243% NaF toothpaste formulation can reduce clinical attachment loss in young adolescents when compared with a 0.243% NaF toothpaste formulation, the magnitude of the difference being greater for patients with deep periodontal pockets at baseline; iv) 0.3% T/2% copolymer/0.243% NaF toothpaste formulation is either similarly or more efficacious in preventing the progression/recurrence of periodontal destruction when compared to a conventional fluoride toothpaste; v) 0.3% T/2% copolymer/0.243% NaF toothpaste formulation seems to be more effective than a fluoride toothpaste formulation in controlling the severity of mucosal inflammation, the incidence of mucosal bleeding as well as reducing probing pocket depth around dental implants.

Volumetric formulation for a class of kinetic models with energy conservation.

PubMed

Sbragaglia, M; Sugiyama, K

2010-10-01

We analyze a volumetric formulation of lattice Boltzmann for compressible thermal fluid flows. The velocity set is chosen with the desired accuracy, based on the Gauss-Hermite quadrature procedure, and tested against controlled problems in bounded and unbounded fluids. The method allows the simulation of thermohydrodyamical problems without the need to preserve the exact space-filling nature of the velocity set, but still ensuring the exact conservation laws for density, momentum, and energy. Issues related to boundary condition problems and improvements based on grid refinement are also investigated.

Formulating viscous hydrodynamics for large velocity gradients

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

Pratt, Scott

2008-02-15

Viscous corrections to relativistic hydrodynamics, which are usually formulated for small velocity gradients, have recently been extended from Navier-Stokes formulations to a class of treatments based on Israel-Stewart equations. Israel-Stewart treatments, which treat the spatial components of the stress-energy tensor {tau}{sub ij} as dynamical objects, introduce new parameters, such as the relaxation times describing nonequilibrium behavior of the elements {tau}{sub ij}. By considering linear response theory and entropy constraints, we show how the additional parameters are related to fluctuations of {tau}{sub ij}. Furthermore, the Israel-Stewart parameters are analyzed for their ability to provide stable and physical solutions for sound waves.more » Finally, it is shown how these parameters, which are naturally described by correlation functions in real time, might be constrained by lattice calculations, which are based on path-integral formulations in imaginary time.« less

'Genipin' - the natural water soluble cross-linking agent and its importance in the modified drug delivery systems: an overview.

PubMed

Manickam, Balamurugan; Sreedharan, Rajesh; Elumalai, Manogaran

2014-01-01

One of the popular approaches in controlling drug delivery from the polymeric carriers is suitably achieved by the inclusion of crosslinking agents into the formulations at different concentrations. Nevertheless, addition of the chemical crosslinkers such as glutaraldehyde, formaldehyde etc, used in the drug delivery systems causes very serious cytotoxic reactions. These chemical crosslinking agents did not offer any significant advantageous effects when compared to the natural crosslinking agents for instance genipin, which is quite less toxic, biocompatible and offers very stable crosslinked products. Based on the earlier reports the safety of this particular natural crosslinker is very well established, since it has been widely used as a Chinese traditional medicine for long-time, isolated from fruits of the plant Gardenia jasminoides Ellis. This concise article largely portrayed the value of this unique natural crosslinker, utilized in controlling the drug delivery from the various formulations.

Formulation and clinical evaluation of silymarin pluronic-lecithin organogels for treatment of atopic dermatitis

PubMed Central

Mady, Fatma M; Essa, Hanaa; El-Ammawi, Tarek; Abdelkader, Hamdy; Hussein, Amal K

2016-01-01

Silymarin is a naturally occurring flavonoid drug; evidence from recent research has highlighted its use as a potential treatment for atopic dermatitis (AD). Both poor water solubility and drug permeability have hindered the percutaneous absorption of silymarin. Formulation of silymarin into pluronic-lecithin organogel (PLO) basis for topical skin delivery is the main aim of this work. Six different PLO formulations were prepared containing various pluronic to lecithin ratios using two cosolvent systems of ethyl alcohol and dimethyl sulfoxide. Formulation 2 (20% pluronic and 3% lecithin) was found to be the optimal base for topical delivery of silymarin as it showed optimum pH, viscosity, drug content, and satisfactory in vitro silymarin permeation. The silymarin PLO formulation significantly relieved inflammatory symptoms of AD such as redness, swelling, and inflammation. These findings warrant the ability for application of these novel silymarin PLO formulations as a novel treatment for AD. PMID:27022248

Formulation and clinical evaluation of silymarin pluronic-lecithin organogels for treatment of atopic dermatitis.

PubMed

Mady, Fatma M; Essa, Hanaa; El-Ammawi, Tarek; Abdelkader, Hamdy; Hussein, Amal K

2016-01-01

Silymarin is a naturally occurring flavonoid drug; evidence from recent research has highlighted its use as a potential treatment for atopic dermatitis (AD). Both poor water solubility and drug permeability have hindered the percutaneous absorption of silymarin. Formulation of silymarin into pluronic-lecithin organogel (PLO) basis for topical skin delivery is the main aim of this work. Six different PLO formulations were prepared containing various pluronic to lecithin ratios using two cosolvent systems of ethyl alcohol and dimethyl sulfoxide. Formulation 2 (20% pluronic and 3% lecithin) was found to be the optimal base for topical delivery of silymarin as it showed optimum pH, viscosity, drug content, and satisfactory in vitro silymarin permeation. The silymarin PLO formulation significantly relieved inflammatory symptoms of AD such as redness, swelling, and inflammation. These findings warrant the ability for application of these novel silymarin PLO formulations as a novel treatment for AD.

Formulation of intumescent flame retardant coatings containing natural-based tea saponin.

PubMed

Qian, Wei; Li, Xiang-Zhou; Wu, Zhi-Ping; Liu, Yan-Xin; Fang, Cong-Cong; Meng, Wei

2015-03-18

Natural product tea saponin (TS), extracted from the nutshell of camellia (Camellia oleifera Abel, Theaceae), was introduced into intumescent flame retardant formulations as blowing agent and carbon source. The formulations of the flame retardant system were optimized to get the optimum proportion of TS, and intumescent flame retardant coatings containing tea saponin (TS-IFRCs) were then prepared. It was found that TS can significantly affect the combustion behavior and the thermal stability of TS-IFRCs evaluated by cone calorimetry and simultaneous thermal analyzer, respectively. It was shown that TS, degraded to water vapor and carbon at high temperatures, can combine with other components to form a well-developed char layer. The char layer was supposed to inhibit erosion upon exposure to heat and oxygen and enhance the flame retardancy of TS-IFRCs. In addition, the smoke release of TS-IFRCs was also studied, which provided a low amount of smoke production.

Nanocrystal for ocular drug delivery: hope or hype.

PubMed

Sharma, Om Prakash; Patel, Viral; Mehta, Tejal

2016-08-01

The complexity of the structure and nature of the eye emanates a challenge for drug delivery to formulation scientists. Lower bioavailability concern of conventional ocular formulation provokes the interest of researchers in the development of novel drug delivery system. Nanotechnology-based formulations have been extensively investigated and found propitious in improving bioavailability of drugs by overcoming ocular barriers prevailing in the eye. The advent of nanocrystals helped in combating the problem of poorly soluble drugs specifically for oral and parenteral drug delivery and led to development of various marketed products. Nanocrystal-based formulations explored for ocular drug delivery have been found successful in achieving increase in retention time, bioavailability, and permeability of drugs across the corneal and conjunctival epithelium. In this review, we have highlighted the ocular physiology and barriers in drug delivery. A comparative analysis of various nanotechnology-based ocular formulations is done with their pros and cons. Consideration is also given to various methods of preparation of nanocrystals with their patented technology. This article highlights the success achieved in conquering various challenges of ocular delivery by the use of nanocrystals while emphasizing on its advantages and application for ocular formulation. The perspectives of nanocrystals as an emerging flipside to explore the frontiers of ocular drug delivery are discussed.

Evaluation of the enzymatic activity and stability of commercial bromelain incorporated in topical formulations.

PubMed

Lourenço, C B; Ataide, J A; Cefali, L C; Novaes, L C D L; Moriel, P; Silveira, E; Tambourgi, E B; Mazzola, P G

2016-10-01

Bromelain is a mixture of proteolytic enzymes found in various tissues of the pineapple plant (Ananas comosus) and other species of Bromeliaceae. Owing to its proteolytic activity, bromelain has been used in the food, medical, pharmaceutical and cosmetic industries, for its cell renewal, anti-ageing, whitening and anti-cellulite properties. This study evaluated the stability of bromelain (commercial powder) incorporated in topical formulations. Bromelain was incorporated at three concentrations, 0.5%, 1.0% and 2.0%, in oil-in-water emulsion and gel, and stored for six months at varying stress conditions. Stability was accessed by measuring the changes in the protein content, enzymatic activity, viscosity, rheology, pH and colour of the selected formulations. The colour of all the samples changed after 180 days of incubation, indicating the concentration-dependence and temperature-sensitive nature of these formulations. No relationship was observed between the changes in the pH, temperature and luminosity exposure in all the samples. Gels proved to be the least preferred base for incorporation of bromelain for use as a topical formulation, owing to its inability to maintain the integrity of bromelain, thereby affecting the formulation characteristics. The emulsion-based formulations at all the concentrations of bromelain were more stable than the gel-based formulation over 180 days of evaluation, at a temperature of 5°C, protected from light. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Formulation of the relativistic moment implicit particle-in-cell method

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

Noguchi, Koichi; Tronci, Cesare; Zuccaro, Gianluca

2007-04-15

A new formulation is presented for the implicit moment method applied to the time-dependent relativistic Vlasov-Maxwell system. The new approach is based on a specific formulation of the implicit moment method that allows us to retain the same formalism that is valid in the classical case despite the formidable complication introduced by the nonlinear nature of the relativistic equations of motion. To demonstrate the validity of the new formulation, an implicit finite difference algorithm is developed to solve the Maxwell's equations and equations of motion. A number of benchmark problems are run: two stream instability, ion acoustic wave damping, Weibelmore » instability, and Poynting flux acceleration. The numerical results are all in agreement with analytical solutions.« less

Comparison and Tensorial Formulation of Inelastic Constitutive Models of Salt Rock Behaviour and Efficient Numerical Implementatio

NASA Astrophysics Data System (ADS)

Nagel, T.; Böttcher, N.; Görke, U. J.; Kolditz, O.

2014-12-01

The design process of geotechnical installations includes the application of numerical simulation tools for safety assessment, dimensioning and long term effectiveness estimations. Underground salt caverns can be used for the storage of natural gas, hydrogen, oil, waste or compressed air. For their design one has to take into account fluctuating internal pressures due to different levels of filling, the stresses imposed by the surrounding rock mass, irregular geometries and possibly heterogeneous material properties [3] in order to estimate long term cavern convergence as well as locally critical wall stresses. Constitutive models applied to rock salt are usually viscoplastic in nature and most often based on a Burgers-type rheological model extended by non-linear viscosity functions and/or plastic friction elements. Besides plastic dilatation, healing and damage are sometimes accounted for as well [2]. The scales of the geotechnical system to be simulated and the laboratory tests from which material parameters are determined are vastly different. The most common material testing modalities to determine material parameters in geoengineering are the uniaxial and the triaxial compression tests. Some constitutive formulations in widespread use are formulated based on equivalent rather than tensorial quantities valid under these specific test conditions and are subsequently applied to heterogeneous underground systems and complex 3D load cases. We show here that this procedure is inappropriate and can lead to erroneous results. We further propose alternative formulations of the constitutive models in question that restore their validity under arbitrary loading conditions. For an efficient numerical simulation, the discussed constitutive models are integrated locally with a Newton-Raphson algorithm that directly provides the algorithmically consistent tangent matrix for the global Newton iteration of the displacement based finite element formulation. Finally, the finite element implementations of the proposed constitutive formulations are employed to simulate an underground salt cavern used for compressed air energy storage with OpenGeoSys [1]. Transient convergence and stress fields are evaluated for typical fluctuating operation pressure regimes.

Accelerated weathering of natural fiber-filled polyethylene composites

Treesearch

Thomas Lundin; Steven M. Cramer; Robert H. Falk; Colin Felton

2004-01-01

The resistance of natural fiber-filled high-density polyethylene composite specimens to ultraviolet- (UV) and moisture-induced degradation was evaluated by measuring changes to flexural properties. High-density polyethylene (HDPE) served as the polymer matrix for four formulations: two formulations without fiber filler and two formulations one containing wood flour and...

Color profiles and stability of acylated and nonacylated anthocyanins as novel pigment sources in a lipstick model: A viable alternative to synthetic colorants.

PubMed

Westfall, Alexandra; Giusti, Mónica

Cosmetics, such as lipstick, can affect an individual's perception of attractiveness and morale. Consumer concern with the safety of synthetic colorants has made the need for alternative natural color sources increasingly urgent. Our goal was to evaluate the feasibility of anthocyanin (ACN) extracts as colorants in lipstick formulations. Lipstick formulations were colored with ACN-rich materials. Accelerated environmental testing typical of the cosmetic industry were used: incubation at 20°, 37°, and 45°C for 12 weeks and temperature abuse cycles between 20°/37°C or -20°/20°C. Color (CIELab) and total monomeric ACN (pH-differential) changes were monitored to determine shelf stability of the product. All formulations exhibited acceptable color for lipsticks. Shelf stability was determined to exceed 2 year based on the accelerated testing conditions. Formulations containing cyanidin as their main ACN were the most stable (elderberry, purple corn, and purple sweet potato). ACNs could be used as suitable alternatives to synthetic colorants in lipid-based topical formulations.

Usnea barbata CO2-supercritical extract in alkyl polyglucoside-based emulsion system: contribution of Confocal Raman imaging to the formulation development of a natural product.

PubMed

Zugic, Ana; Lunter, Dominique Jasmin; Daniels, Rolf; Pantelic, Ivana; Tasic Kostov, Marija; Tadic, Vanja; Misic, Dusan; Arsic, Ivana; Savic, Snezana

2016-08-01

Topical treatment of skin infections is often limited by drawbacks related to both antimicrobial agents and their vehicles. In addition, considering the growing promotion of natural therapeutic products, our objective was to develop and evaluate naturally-based emulsion system, as prospective topical formulation for skin infections-treatment. Therefore, alkyl polyglucoside surfactants were used for stabilization of a vehicle serving as potential carrier for supercritical CO2-extract of Usnea barbata, lichen with well-documented antimicrobial activity, incorporated using two protocols and three concentrations. Comprehensive physicochemical characterization suggested possible involvement of extract's particles in stabilization of the investigated system. Raman spectral imaging served as the key method in disclosing extract's particles potential to participate in the microstructure of the tested emulsion system via three mechanisms: (1) particle-particle aggregation, (2) adsorption at the oil-water interface and (3) hydrophobic particle-surfactant interactions. Stated extract-vehicle interaction proved to be correlated to the preparation procedure and extract concentration on one hand and to affect the physicochemical and biopharmaceutical features of investigated system, on the other hand. Thereafter, formulation with the best preliminary stability and liberation profile was selected for further efficiency and in vivo skin irritation potential evaluation, implying pertinent in vitro antimicrobial activity against G+ bacteria and overall satisfying preliminary safety profile.

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

PubMed

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

2016-12-01

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

Physical parameters of chlorphenamine maleate suppositories and its release as a function of particle size, concentration and nature of the base.

PubMed

el-Din, E N; Mursi, N M; Elbary, A A; Foda, N

1977-01-01

Suppositories of chlorphenamine maleate were formulated. The influence of particle size and percentage concentration of chlorphenamine maleate on the physical standards of its suppositories as well as the release of the drug from oily base (cacao butter), water-soluble base (carbowax) and emulsifying base (Witepsol) has been investigated.

Innovative Formulation Combining Al, Zr and Si Precursors to Obtain Anticorrosion Hybrid Sol-Gel Coating.

PubMed

Genet, Clément; Menu, Marie-Joëlle; Gavard, Olivier; Ansart, Florence; Gressier, Marie; Montpellaz, Robin

2018-05-10

The aim of our study is to improve the aluminium alloy corrosion resistance with Organic-Inorganic Hybrid (OIH) sol-gel coating. Coatings are obtained from unusual formulation with precursors mixing: glycidoxypropyltrimethoxysilane (GPTMS), zirconium (IV) propoxide (TPOZ) and aluminium tri-sec-butoxide (ASB). This formulation was characterized and compared with sol formulations GPTMS/TPOZ and GPTMS/ASB. In each formulation, a corrosion inhibitor, cerium (III) nitrate hexahydrate, is employed to improve the corrosion performance. Coatings obtained from sol based on GPTMS/TPOZ/ASB have good anti-corrosion performances with Natural Salt Spray (NSS) resistance of 500 h for a thickness lower than 4 µm. Contact angle measurement showed a coating hydrophobic behaviour. To understand these performances, nuclear magnetic resonance (NMR) analyses were performed, results make sol-gel coating condensation evident and are in very good agreement with previous results.

Torsional vibration of a cracked rod by variational formulation and numerical analysis

NASA Astrophysics Data System (ADS)

Chondros, T. G.; Labeas, G. N.

2007-04-01

The torsional vibration of a circumferentially cracked cylindrical shaft is studied through an "exact" analytical solution and a numerical finite element (FE) analysis. The Hu-Washizu-Barr variational formulation is used to develop the differential equation and the boundary conditions of the cracked rod. The equations of motion for a uniform cracked rod in torsional vibration are derived and solved, and the Rayleigh quotient is used to further approximate the natural frequencies of the cracked rod. Results for the problem of the torsional vibration of a cylindrical shaft with a peripheral crack are provided through an analytical solution based on variational formulation to derive the equation of motion and a numerical analysis utilizing a parametric three-dimensional (3D) solid FE model of the cracked rod. The crack is modelled as a continuous flexibility based on fracture mechanics principles. The variational formulation results are compared with the FE alternative. The sensitivity of the FE discretization with respect to the analytical results is assessed.

Molecular properties via a subsystem density functional theory formulation: a common framework for electronic embedding.

PubMed

Höfener, Sebastian; Gomes, André Severo Pereira; Visscher, Lucas

2012-01-28

In this article, we present a consistent derivation of a density functional theory (DFT) based embedding method which encompasses wave-function theory-in-DFT (WFT-in-DFT) and the DFT-based subsystem formulation of response theory (DFT-in-DFT) by Neugebauer [J. Neugebauer, J. Chem. Phys. 131, 084104 (2009)] as special cases. This formulation, which is based on the time-averaged quasi-energy formalism, makes use of the variation Lagrangian techniques to allow the use of non-variational (in particular: coupled cluster) wave-function-based methods. We show how, in the time-independent limit, we naturally obtain expressions for the ground-state DFT-in-DFT and WFT-in-DFT embedding via a local potential. We furthermore provide working equations for the special case in which coupled cluster theory is used to obtain the density and excitation energies of the active subsystem. A sample application is given to demonstrate the method. © 2012 American Institute of Physics

A naturally-inspired, curcumin-based lecithin formulation (Meriva® formulated as the finished product Algocur®) alleviates the osteo-muscular pain conditions in rugby players.

PubMed

Di Pierro, F; Zacconi, P; Bertuccioli, A; Togni, S; Eggenhoffner, R; Giacomelli, L; Scaltrini, S

2017-11-01

Curcumin is one of the most investigated phytochemical products because of its low toxicity and its broad spectrum of bioactivity, including anti-inflammatory and analgesic properties. A new delivery form of curcumin, resorting to phosphatidylcholine (Meriva®, formulated as the finished product Algocur®) has been developed to increase its bioavailability. In this study, we tested the efficacy and safety of a Meriva®-based product in rugby players suffering by different osteo-muscular pain conditions PATIENTS AND METHODS: In this pilot study, 50 male rugby players with osteo-muscular pain due to traumatic injuries, physical overload or acute episode of chronic pain were recruited and treated with conventional analgesic drugs (n = 25) or Meriva®-based product (n = 25) for a maximum of 10 days. The pain perception and the functio laesa were evaluated at baseline and after 1, 3, 6, 10 and 20 days from the initiation of the treatment protocol. Treatment tolerability, compliance, and adverse events were also reported. During the study, the analgesic effect decreased in both treated group compared to baseline, starting from the third day of treatment. Similarly, the impaired physical function evaluated after 3, 6, 10 and 20 days improved in Meriva®-based product treated group and in subjects treated with conventional analgesic drugs, compared to the baseline condition. The percentage of excellent adherence to treatment or tolerability was higher in the Meriva®-based product treated group. Only 1 (4%) subject treated with Meriva®-based product experienced adverse events whereas 4 (16%) subjects treated with conventional analgesic drugs reported gastric pain as an adverse event. Despite the small sample size and the group heterogeneity, this study suggests that the naturally-derived, curcumin-based delivery form, Meriva® (formulated as the finished product Algocur®), could represent a promising safe, analgesic remedy in painful osteo-muscular conditions associated with intense, high impact, physical activities.

A sight on protein-based nanoparticles as drug/gene delivery systems.

PubMed

Salatin, Sara; Jelvehgari, Mitra; Maleki-Dizaj, Solmaz; Adibkia, Khosro

2015-01-01

Polymeric nanomaterials have extensively been applied for the preparation of targeted and controlled release drug/gene delivery systems. However, problems involved in the formulation of synthetic polymers such as using of the toxic solvents and surfactants have limited their desirable applications. In this regard, natural biomolecules including proteins and polysaccharide are suitable alternatives due to their safety. According to literature, protein-based nanoparticles possess many advantages for drug and gene delivery such as biocompatibility, biodegradability and ability to functionalize with targeting ligands. This review provides a general sight on the application of biodegradable protein-based nanoparticles in drug/gene delivery based on their origins. Their unique physicochemical properties that help them to be formulated as pharmaceutical carriers are also discussed.

Optimality approaches to describe characteristic fluvial patterns on landscapes

PubMed Central

Paik, Kyungrock; Kumar, Praveen

2010-01-01

Mother Nature has left amazingly regular geomorphic patterns on the Earth's surface. These patterns are often explained as having arisen as a result of some optimal behaviour of natural processes. However, there is little agreement on what is being optimized. As a result, a number of alternatives have been proposed, often with little a priori justification with the argument that successful predictions will lend a posteriori support to the hypothesized optimality principle. Given that maximum entropy production is an optimality principle attempting to predict the microscopic behaviour from a macroscopic characterization, this paper provides a review of similar approaches with the goal of providing a comparison and contrast between them to enable synthesis. While assumptions of optimal behaviour approach a system from a macroscopic viewpoint, process-based formulations attempt to resolve the mechanistic details whose interactions lead to the system level functions. Using observed optimality trends may help simplify problem formulation at appropriate levels of scale of interest. However, for such an approach to be successful, we suggest that optimality approaches should be formulated at a broader level of environmental systems' viewpoint, i.e. incorporating the dynamic nature of environmental variables and complex feedback mechanisms between fluvial and non-fluvial processes. PMID:20368257

Novel cosmetic formulations containing a biosurfactant from Lactobacillus paracasei.

PubMed

Ferreira, A; Vecino, X; Ferreira, D; Cruz, J M; Moldes, A B; Rodrigues, L R

2017-07-01

Cosmetic and personal care products including toothpaste, shampoo, creams, makeup, among others, are usually formulated with petroleum-based surfactants, although in the last years the consume trend for "green" products is inducing the replacement of surface-active agents in these formulations by natural surfactants, so-called biosurfactants. In addition to their surfactant capacity, many biosurfactants can act as good emulsifiers, which is an extra advantage in the preparation of green cosmetic products. In this work, a biosurfactant obtained from Lactobacillus paracasei was used as a stabilizing agent in oil-in-water emulsions containing essential oils and natural antioxidant extract. In the presence of biosurfactant, maximum percentages of emulsion volumes (EV=100%) were observed, with droplets sizes about 199nm. These results were comparable with the ones obtained using sodium dodecyl sulfate (SDS), a synthetic well known surfactant with high emulsify capacity. Moreover, the biosurfactant and emulsions cytotoxicity was evaluated using a mouse fibroblast cell line. Solutions containing 5g/L of biosurfactant presented cell proliferation values of 97%, whereas 0.5g/L of SDS showed a strong inhibitory effect. Overall, the results herein gathered are very promising towards the development of new green cosmetic formulations. Copyright © 2017 Elsevier B.V. All rights reserved.

Novel cyclodextrin nanosponges for delivery of calcium in hyperphosphatemia.

PubMed

Shende, Pravin; Deshmukh, Kiran; Trotta, Fransesco; Caldera, Fabrizio

2013-11-01

Cyclodextrin nanosponges are solid, porous nanoparticulate three dimensional structures, have been used as delivery system of different drugs. In this work, new cyclodextrin-based nanosponges of calcium carbonate were prepared by polymer condensation method to release the calcium in controlled manner in the treatment of hyperphosphatemia as novel carriers. SEM measurements revealed their roughly spherical shape, porous nature and mean particle size of about 400 nm. Zeta potentials of the nanosponges were sufficiently high to obtain stable formulations. The encapsulation efficiencies of calcium in nanosponge formulations were found to be 81-95%. The moisture contents of the nanosponges were in the range of 0.1-0.7%. The optimized formulation produces enteric and controlled release kinetics of calcium in the management and treatment of hyperphosphatemia. It was also observed that calcium ions bound efficiently to free phosphate in a pH-dependent fashion especially at pH 7. In accelerated stability study no significant changes occurred in physical appearance, size and nature of drug in formulation for 3 months. The results of FTIR and DSC confirmed that calcium carbonate was encapsulated in nanosponges structure. Copyright © 2013 Elsevier B.V. All rights reserved.

Creative Report Writing in Undergraduate Organic Chemistry Laboratory Inspires Nonmajors

ERIC Educational Resources Information Center

Henary, Maged; Owens, Eric A.; Tawney, Joseph G.

2015-01-01

Laboratory-based courses require students to compose reports based on the performed experiments to assess their overall understanding of the presented material; unfortunately, the sterile and formulated nature of the laboratory report disinterests most students. As a result, the outcome is a lower-quality product that does not reveal full…

Reduced-Volume Fracture Toughness Characterization for Transparent Polymers

DTIC Science & Technology

2015-03-21

Caruthers et al. (2004) developed a thermodynamically consistent, nonlinear viscoelastic bulk constitutive model based on a potential energy clock ( PEC ...except that relaxation times change. Because of its formulation, the PEC model predicts mechanical yield as a natural consequence of relaxation...softening type of behavior, but hysteresis effects are not naturally accounted for. Adolf et al. (2009) developed a method of simplifying the PEC model

Nanobiotechnology: Cell Membrane-Based Delivery Systems.

PubMed

Zhang, Pengfei; Liu, Gang; Chen, Xiaoyuan

2017-04-01

The increasingly rapid pace of research in the field of bioinspired drug delivery systems is revealing the promise of cell membrane-based nanovesicles for biomedical applications. Those cell membrane-based nanoparticles combine the natural functionalities of cell plasma membranes and the bioengineering flexibility of synthetic nanomaterials, and such versatility provides a means of designing exciting new drug formulations for personalized treatment in future nanomedicine.

Trends in insect repellent formulations: A review.

PubMed

Tavares, Melanie; da Silva, Márcio Robert Mattos; de Oliveira de Siqueira, Luciana Betzler; Rodrigues, Raphaela Aparecida Schuenck; Bodjolle-d'Almeida, Lolita; Dos Santos, Elisabete Pereira; Ricci-Júnior, Eduardo

2018-03-25

The use of natural and synthetic repellents, marketed in different pharmaceutical forms, is growing in the world due to the emerging vector-borne viral diseases as Dengue, Zika, Chikungunya, Yellow Fever and Malaria. The choice of the ideal formulation will depend on a series of factors to be analyzed: type of repellent active (natural or synthetic), pharmaceutical forms (spray, lotion, cream, gel), action time duration (short or long), environment of exposure and the user (adult, pregnant women, children, newborn). The most used repellents are DEET, IR3535 (Ethyl Butylacetylaminopropionate) (EB), Icaridin (Picaridin) and essential oils, each of them presenting advantages and disadvantages. DEET is the oldest and the most powerful repellent available in the market, thus being the reference standard. For this reason, there are many classic formulations available in the market containing the chemical component DEET in spray forms and lotions. However, due to its toxicity, DEET is not recommended for children up to 6 months and pregnant women. DEET has been an option along with other market-shared products as IR3535 and Icaridin (Picaridin), which present less toxicity in their composition. IR3535 is the less toxic and may be prescribed for children over 6 months of age and pregnant women so that they have been the best option because of the lower toxicity levels presented. IR3535 is the one that has the lowest toxicity level among the three options and may be prescribed for children above 6 months of age and pregnant women. Icaridin is as potent as DEET, but less toxic, and has the advantage of having the long-lasting action among the aforementioned repellents. The new formulations have been based on controlled release systems (CRS). The CRSs for repellents comprise polymer micro/nanocapsules, micro/solid lipid nanoparticles, nanoemulsions/microemulsions, liposomes/niosomes, nanostructured hydrogels and cyclodextrins. There are many formulations based on micro and nanocapsules containing DEET and essential oils to increase repellent action time duration and decrease permeation and consequently, systemic toxicity. The development of new formulations for the IR3535 and Icaridin is a research field yet to be explored. The current trend is the use of natural repellent actives such as essential oils, which present low toxicity, do not harm the environment, but present reduced repellent action time due to rapid evaporation after skin application. CRSs have been used as vehicle of natural repellents to improve long-lasting repellent action, reduce skin permeation and systemic effects. Copyright © 2018 Elsevier B.V. All rights reserved.

Metabolomics Analysis of Effects of Commercial Soy-based Protein Products in Red Drum (Sciaenops ocellatus).

PubMed

Casu, Fabio; Watson, Aaron M; Yost, Justin; Leffler, John W; Gaylord, Thomas Gibson; Barrows, Frederic T; Sandifer, Paul A; Denson, Michael R; Bearden, Daniel W

2017-07-07

We investigated the metabolic effects of four different commercial soy-based protein products on red drum fish (Sciaenops ocellatus) using nuclear magnetic resonance (NMR) spectroscopy-based metabolomics along with unsupervised principal component analysis (PCA) to evaluate metabolic profiles in liver, muscle, and plasma tissues. Specifically, during a 12 week feeding trial, juvenile red drum maintained in an indoor recirculating aquaculture system were fed four different commercially available soy formulations, containing the same amount of crude protein, and two reference diets as performance controls: a 60% soybean meal diet that had been used in a previous trial in our lab and a natural diet. Red drum liver, muscle, and plasma tissues were sampled at multiple time points to provide a more accurate snapshot of specific metabolic states during the grow-out. PCA score plots derived from NMR spectroscopy data sets showed significant differences between fish fed the natural diet and the soy-based diets, in both liver and muscle tissues. While red drum tolerated the inclusion of soy with good feed conversion ratios, a comparison to fish fed the natural diet revealed that the soy-fed fish in this study displayed a distinct metabolic signature characterized by increased protein and lipid catabolism, suggesting an energetic imbalance. Furthermore, among the soy-based formulations, one diet showed a more pronounced catabolic signature.

The role of probabilistic formulations of sediment transport aimed at describing the behavior of soil-mantled hillslopes over geomorphic timescales (Invited)

NASA Astrophysics Data System (ADS)

Furbish, D. J.; Roering, J. J.

2013-12-01

Recent discussions of local versus nonlocal sediment transport on hillslopes offer a lens for considering uncertainty in formulations of transport rates that are aimed at characterizing patchy, intermittent sediment motions in steeplands. Here we describe a general formulation for transport that is based on a convolution integral of the factors controlling the entrainment and disentrainment of sediment particles on a hillslope. In essence, such a formulation represents a ';flux' version of the Master equation, a general probabilistic (kinematic) formulation of mass conservation. As such, with the relevant physics invoked to represent entrainment and disentrainment, a nonlocal formulation quite happily accommodates local transport (and looks/behaves like a local formulation), as well as nonlocal transport, depending on the characteristic length scale of particle motions relative to the length scale at which the factors controlling particle transport are defined or measured. Nonetheless, nonlocal formulations of the sediment flux have mostly (but not entirely) outpaced experimental and field-based observations needed to inform the theory. At risk is bringing to bear a sophisticated mathematics that is not supported by our uncertain understanding of the processes involved. Experimental and field-based measurements of entrainment rates and particle travel distances are difficult to obtain, notably given the intermittency of many hillslope transport processes and the slow rates of change in hillslope morphology. A ';test' of a specific nonlocal formulation applied to hillslope evolution must therefore in part rest on consistency between measured hillslope configurations and predicted (i.e., modeled) hillslope configurations predicated on the proposed nonlocal formulation, assuming sufficient knowledge of initial and boundary conditions. On the other hand, because of its probabilistic basis, the formulation is in principle well suited to the task of describing transport relevant to geomorphic timescales -- in view of the stochastic nature of the transport processes occurring over these timescales and the uncertainty of our understanding of the physics involved. Moreover, in its basic form, the nonlocal formulation of the sediment flux is such that appropriate physics can be readily embedded within it as we learn more. And, the formulation is space-time averaged in a way that accommodates discontinuous (patchy, intermittent) sediment motions.

Evaluation of hypericin-loaded solid lipid nanoparticles: physicochemical properties, photostability and phototoxicity.

PubMed

Youssef, Tareq; Fadel, Maha; Fahmy, Rania; Kassab, Kawser

2012-01-01

Hypericin (HYP), a natural photosensitizer, has powerful photo-oxidizing ability, tumor-seeking characteristics, and minimal dark toxicity; nevertheless, it has proven high lipid solubility compared to its sparingly water soluble nature. Therefore, its formulation into solid lipid nanoparticles (SLNs) has attracted increasing attention as a potential drug-delivery carrier. Two HYP-loaded SLNs formulations were prepared utilizing microemulsion-based technique. Thereafter, the physicochemical properties of the formulations were investigated and evaluated. HYP-loaded SLNs showed spherical shape with mean particle size ranging from 200-300 nm for both formulations (FA and FB). The encapsulation efficiencies reached above 80% and FA showed significant higher encapsulation than FB (P<0.05), also, the thermal analysis using differential scanning calorimetry (DSC) indicated good compatibility between hypericin and lipids forming the cores in both formulations. Spectroscopic measurements of the photostability study showed that hypericin encapsulation into SLNs improved its photostability, compared to free HYP in 0.1% ethanolic solution. However, photocytotoxicity studies on HepG2 cells revealed an evident inhibition of the photodynamic efficacy of HYP-loaded SLNs, compared to free HYP. In conclusion, although the elevated entrapment efficiency of HYP into SLNs increased its photostability, it decreased its phototoxicity which might be due to the quenching deactivation of HYP molecules resulting from SLN compactness and thickness structure. © 2012 Informa Healthcare USA, Inc.

Dissofilm: A Novel Approach for Delivery of Phenobarbital; Design and Characterization

PubMed Central

Yellanki, SK; Jagtap, S; Masareddy, R

2011-01-01

An attempt to develop and evaluate mouth-dissolving film of phenobarbital for quick effect in treatment of epilepsy occurring in pediatric population has been made in the present study. Suitable film formers and plasticizers are selected based on optimization studies. Effect of superdisintegrants in formulation of mouth dissolving films at different concentrations has been investigated. Films were prepared by solvent casting method. The prepared films were evaluated for physicochemical parameters, in vitro disintegration and dissolution time, in vitro release rate study, stability study, and in vivo animal safety study. The best formulation was found to be F3 showing 96.57% drug release in 14 min, following first-order kinetics. X-Ray diffraction studies show change in crystalline nature of drug in formulation. In vivo studies in hamster reports effective and safe use of formulation in animals. PMID:21897656

A Variational Formulation of Macro-Particle Algorithms for Kinetic Plasma Simulations

NASA Astrophysics Data System (ADS)

Shadwick, B. A.

2013-10-01

Macro-particle based simulations methods are in widespread use in plasma physics; their computational efficiency and intuitive nature are largely responsible for their longevity. In the main, these algorithms are formulated by approximating the continuous equations of motion. For systems governed by a variational principle (such as collisionless plasmas), approximations of the equations of motion is known to introduce anomalous behavior, especially in system invariants. We present a variational formulation of particle algorithms for plasma simulation based on a reduction of the distribution function onto a finite collection of macro-particles. As in the usual Particle-In-Cell (PIC) formulation, these macro-particles have a definite momentum and are spatially extended. The primary advantage of this approach is the preservation of the link between symmetries and conservation laws. For example, nothing in the reduction introduces explicit time dependence to the system and, therefore, the continuous-time equations of motion exactly conserve energy; thus, these models are free of grid-heating. In addition, the variational formulation allows for constructing models of arbitrary spatial and temporal order. In contrast, the overall accuracy of the usual PIC algorithm is at most second due to the nature of the force interpolation between the gridded field quantities and the (continuous) particle position. Again in contrast to the usual PIC algorithm, here the macro-particle shape is arbitrary; the spatial extent is completely decoupled from both the grid-size and the ``smoothness'' of the shape; smoother particle shapes are not necessarily larger. For simplicity, we restrict our discussion to one-dimensional, non-relativistic, un-magnetized, electrostatic plasmas. We comment on the extension to the electromagnetic case. Supported by the US DoE under contract numbers DE-FG02-08ER55000 and DE-SC0008382.

Strawberry-Based Cosmetic Formulations Protect Human Dermal Fibroblasts against UVA-Induced Damage

PubMed Central

Gasparrini, Massimiliano; Forbes-Hernandez, Tamara Y.; Afrin, Sadia; Reboredo-Rodriguez, Patricia; Cianciosi, Danila; Mezzetti, Bruno; Quiles, Josè L.; Bompadre, Stefano; Battino, Maurizio; Giampieri, Francesca

2017-01-01

Extreme exposure of skin to Ultraviolet A (UVA)-radiation may induce a dysregulated production of reactive oxygen species (ROS) which can interact with cellular biomolecules leading to oxidative stress, inflammation, DNA damage, and alteration of cellular molecular pathways, responsible for skin photoaging, hyperplasia, erythema, and cancer. For these reasons, the use of dietary natural bioactive compounds with remarkable antioxidant activity could be a strategic tool to counteract these UVA-radiation-caused deleterious effects. Thus, the purpose of the present work was to test the efficacy of strawberry (50 μg/mL)-based formulations supplemented with Coenzyme Q10 (100 μg/mL) and sun protection factor 10 in human dermal fibroblasts irradiated with UVA-radiation. The apoptosis rate, the amount of intracellular reactive oxygen species (ROS) production, the expression of proteins involved in antioxidant and inflammatory response, and mitochondrial functionality were evaluated. The results showed that the synergic topical use of strawberry and Coenzyme Q10 provided a significant (p < 0.05) photoprotective effect, reducing cell death and ROS, increasing antioxidant defense, lowering inflammatory markers, and improving mitochondrial functionality. The obtained results suggest the use of strawberry-based formulations as an innovative, natural, and useful tool for the prevention of UVA exposure-induced skin diseases in order to decrease or substitute the amount of synthetic sunscreen agents. PMID:28613256

Human motion planning based on recursive dynamics and optimal control techniques

NASA Technical Reports Server (NTRS)

Lo, Janzen; Huang, Gang; Metaxas, Dimitris

2002-01-01

This paper presents an efficient optimal control and recursive dynamics-based computer animation system for simulating and controlling the motion of articulated figures. A quasi-Newton nonlinear programming technique (super-linear convergence) is implemented to solve minimum torque-based human motion-planning problems. The explicit analytical gradients needed in the dynamics are derived using a matrix exponential formulation and Lie algebra. Cubic spline functions are used to make the search space for an optimal solution finite. Based on our formulations, our method is well conditioned and robust, in addition to being computationally efficient. To better illustrate the efficiency of our method, we present results of natural looking and physically correct human motions for a variety of human motion tasks involving open and closed loop kinematic chains.

Interpersonal Persuasion I: Formulation and First Test of a Rules-Based Theory.

ERIC Educational Resources Information Center

Lulofs, Roxane Salyer

A great deal of research has been done in the area of "compliance-message" tactics and strategies, but this research has not produced a coherent framework for studying this interpersonal communication process. Based on six axioms concerning the nature of communication behavior in general and on one postulate and five theorems defining…

Figure-Ground Segmentation Using Factor Graphs

PubMed Central

Shen, Huiying; Coughlan, James; Ivanchenko, Volodymyr

2009-01-01

Foreground-background segmentation has recently been applied [26,12] to the detection and segmentation of specific objects or structures of interest from the background as an efficient alternative to techniques such as deformable templates [27]. We introduce a graphical model (i.e. Markov random field)-based formulation of structure-specific figure-ground segmentation based on simple geometric features extracted from an image, such as local configurations of linear features, that are characteristic of the desired figure structure. Our formulation is novel in that it is based on factor graphs, which are graphical models that encode interactions among arbitrary numbers of random variables. The ability of factor graphs to express interactions higher than pairwise order (the highest order encountered in most graphical models used in computer vision) is useful for modeling a variety of pattern recognition problems. In particular, we show how this property makes factor graphs a natural framework for performing grouping and segmentation, and demonstrate that the factor graph framework emerges naturally from a simple maximum entropy model of figure-ground segmentation. We cast our approach in a learning framework, in which the contributions of multiple grouping cues are learned from training data, and apply our framework to the problem of finding printed text in natural scenes. Experimental results are described, including a performance analysis that demonstrates the feasibility of the approach. PMID:20160994

Development and evaluation of transdermal organogels containing nicorandil.

PubMed

Madan, J R; Sagar, Banode; Chellappan, Dinesh K; Dua, Kamal

2013-01-01

The objective of the study was to formulate a transdermal product containing Nicorandil as a model drug, because it has been first drug of choice to treat angina and hypertension. A further objective was to reduce its side effects. The transdermal product was prepared using various synthetic and natural gelling agents such as Carbopol 934p, Carbopol 974p, HPMC K15M and HPMC K100M. Various penetration enhancers were incorporated to enhance the diffusion across the rat skin. A further objective was to formulate organogels and minimize the concentration of penetration enhancer to 50% of the concentration used in gels and yet to achieve the maximum drug release. The prepared formulations were evaluated for their physical appearance, viscosity, spreadability, drug content and freeze thaw cycle. Based on in vitro studies across rat skin and human cadaver skin it was concluded that Nicrorandil transdermal organogel formulation using HPMC K100M with 2% w/w Transcutol-P shows increase in cumulative diffusion of Nicorandil amongst all other formulations.

Structure-Property Relationships of Architectural Coatings by Neutron Methods

NASA Astrophysics Data System (ADS)

Nakatani, Alan

2015-03-01

Architectural coatings formulations are multi-component mixtures containing latex polymer binder, pigment, rheology modifiers, surfactants, and colorants. In order to achieve the desired flow properties for these formulations, measures of the underlying structure of the components as a function of shear rate and the impact of formulation variables on the structure is necessary. We have conducted detailed measurements to understand the evolution under shear of local microstructure and larger scale mesostructure in model architectural coatings formulations by small angle neutron scattering (SANS) and ultra small angle neutron scattering (USANS), respectively. The SANS results show an adsorbed layer of rheology modifier molecules exist on the surface of the latex particles. However, the additional hydrodynamic volume occupied by the adsorbed surface layer is insufficient to account for the observed viscosity by standard hard sphere suspension models (Krieger-Dougherty). The USANS results show the presence of latex aggregates, which are fractal in nature. These fractal aggregates are the primary structures responsible for coatings formulation viscosity. Based on these results, a new model for the viscosity of coatings formulations has been developed, which is capable of reproducing the observed viscosity behavior.

Natural oils and waxes: studies on stick bases.

PubMed

Budai, Lívia; Antal, István; Klebovich, Imre; Budai, Marianna

2012-01-01

The objective of the present article was to examine the role of origin and quantity of selected natural oils and waxes in the determination of the thermal properties and hardness of stick bases. The natural oils and waxes selected for the study were sunflower, castor, jojoba, and coconut oils. The selected waxes were yellow beeswax, candelilla wax, and carnauba wax. The hardness of the formulations is a critical parameter from the aspect of their application. Hardness was characterized by the measurement of compression strength along with the softening point, the drop point, and differential scanning calorimetry (DSC). It can be concluded that coconut oil, jojoba oil, and carnauba wax have the greatest influence on the thermal parameters of stick bases.

Natural additives and agricultural wastes in biopolymer formulations for food packaging.

PubMed

Valdés, Arantzazu; Mellinas, Ana Cristina; Ramos, Marina; Garrigós, María Carmen; Jiménez, Alfonso

2014-01-01

The main directions in food packaging research are targeted toward improvements in food quality and food safety. For this purpose, food packaging providing longer product shelf-life, as well as the monitoring of safety and quality based upon international standards, is desirable. New active packaging strategies represent a key area of development in new multifunctional materials where the use of natural additives and/or agricultural wastes is getting increasing interest. The development of new materials, and particularly innovative biopolymer formulations, can help to address these requirements and also with other packaging functions such as: food protection and preservation, marketing and smart communication to consumers. The use of biocomposites for active food packaging is one of the most studied approaches in the last years on materials in contact with food. Applications of these innovative biocomposites could help to provide new food packaging materials with improved mechanical, barrier, antioxidant, and antimicrobial properties. From the food industry standpoint, concerns such as the safety and risk associated with these new additives, migration properties and possible human ingestion and regulations need to be considered. The latest innovations in the use of these innovative formulations to obtain biocomposites are reported in this review. Legislative issues related to the use of natural additives and agricultural wastes in food packaging systems are also discussed.

Natural additives and agricultural wastes in biopolymer formulations for food packaging

NASA Astrophysics Data System (ADS)

Valdés, Arantzazu; Mellinas, Ana Cristina; Ramos, Marina; Garrigós, María Carmen; Jiménez, Alfonso

2014-02-01

The main directions in food packaging research are targeted towards improvements in food quality and food safety. For this purpose, food packaging providing longer product shelf-life, as well as the monitoring of safety and quality based upon international standards, is desirable. New active packaging strategies represent a key area of development in new multifunctional materials where the use of natural additives and/or agricultural wastes is getting increasing interest. The development of new materials, and particularly innovative biopolymer formulations, can help to address these requirements and also with other packaging functions such as: food protection and preservation, marketing and smart communication to consumers. The use of biocomposites for active food packaging is one of the most studied approaches in the last years on materials in contact with food. Applications of these innovative biocomposites could help to provide new food packaging materials with improved mechanical, barrier, antioxidant and antimicrobial properties. From the food industry standpoint, concerns such as the safety and risk associated with these new additives, migration properties and possible human ingestion and regulations need to be considered. The latest innovations in the use of these innovative formulations to obtain biocomposites are reported in this review. Legislative issues related to the use of natural additives and agricultural wastes in food packaging systems are also discussed.

Natural additives and agricultural wastes in biopolymer formulations for food packaging

PubMed Central

Valdés, Arantzazu; Mellinas, Ana Cristina; Ramos, Marina; Garrigós, María Carmen; Jiménez, Alfonso

2014-01-01

The main directions in food packaging research are targeted toward improvements in food quality and food safety. For this purpose, food packaging providing longer product shelf-life, as well as the monitoring of safety and quality based upon international standards, is desirable. New active packaging strategies represent a key area of development in new multifunctional materials where the use of natural additives and/or agricultural wastes is getting increasing interest. The development of new materials, and particularly innovative biopolymer formulations, can help to address these requirements and also with other packaging functions such as: food protection and preservation, marketing and smart communication to consumers. The use of biocomposites for active food packaging is one of the most studied approaches in the last years on materials in contact with food. Applications of these innovative biocomposites could help to provide new food packaging materials with improved mechanical, barrier, antioxidant, and antimicrobial properties. From the food industry standpoint, concerns such as the safety and risk associated with these new additives, migration properties and possible human ingestion and regulations need to be considered. The latest innovations in the use of these innovative formulations to obtain biocomposites are reported in this review. Legislative issues related to the use of natural additives and agricultural wastes in food packaging systems are also discussed. PMID:24790975

PLGA particulate delivery systems for subunit vaccines: Linking particle properties to immunogenicity.

PubMed

Silva, A L; Soema, P C; Slütter, B; Ossendorp, F; Jiskoot, W

2016-04-02

Among the emerging subunit vaccines are recombinant protein- and synthetic peptide-based vaccine formulations. However, proteins and peptides have a low intrinsic immunogenicity. A common strategy to overcome this is to co-deliver (an) antigen(s) with (an) immune modulator(s) by co-encapsulating them in a particulate delivery system, such as poly(lactic-co-glycolic acid) (PLGA) particles. Particulate PLGA formulations offer many advantages for antigen delivery as they are biocompatible and biodegradable; can protect the antigens from degradation and clearance; allow for co-encapsulation of antigens and immune modulators; can be targeted to antigen presenting cells; and their particulate nature can increase uptake and cross-presentation by mimicking the size and shape of an invading pathogen. In this review we discuss the pros and cons of using PLGA particulate formulations for subunit vaccine delivery and provide an overview of formulation parameters that influence their adjuvanticity and the ensuing immune response.

Vegetable Oils as Alternative Solvents for Green Oleo-Extraction, Purification and Formulation of Food and Natural Products.

PubMed

Yara-Varón, Edinson; Li, Ying; Balcells, Mercè; Canela-Garayoa, Ramon; Fabiano-Tixier, Anne-Sylvie; Chemat, Farid

2017-09-05

Since solvents of petroleum origin are now strictly regulated worldwide, there is a growing demand for using greener, bio-based and renewable solvents for extraction, purification and formulation of natural and food products. The ideal alternative solvents are non-volatile organic compounds (VOCs) that have high dissolving power and flash point, together with low toxicity and less environmental impact. They should be obtained from renewable resources at a reasonable price and be easy to recycle. Based on the principles of Green Chemistry and Green Engineering, vegetable oils could become an ideal alternative solvent to extract compounds for purification, enrichment, or even pollution remediation. This review presents an overview of vegetable oils as solvents enriched with various bioactive compounds from natural resources, as well as the relationship between dissolving power of non-polar and polar bioactive components with the function of fatty acids and/or lipid classes in vegetable oils, and other minor components. A focus on simulation of solvent-solute interactions and a discussion of polar paradox theory propose a mechanism explaining the phenomena of dissolving polar and non-polar bioactive components in vegetable oils as green solvents with variable polarity.

Moisturizing and Antiinflammatory Properties of Cosmetic Formulations Containing Centella asiatica Extract

PubMed Central

Ratz-Łyko, A.; Arct, J.; Pytkowska, K.

2016-01-01

Centella asiatica extract is a rich source of natural bioactive substances, triterpenoid saponins, flavonoids, phenolic acids, triterpenic steroids, amino acids and sugars. Thus, many scavenging free radicals, exhibit antiinflammatory activity and affect on the stratum corneum hydration and epidermal barrier function. The aim of the present study was to evaluate the in vivo moisturizing and antiinflammatory properties of cosmetic formulations (oil-in-water emulsion cream and hydrogel) containing different concentrations of Centella asiatica extract. The study was conducted over four weeks on a group of 25 volunteers after twice a day application of cosmetic formulations with Centella asiatica extract (2.5 and 5%, w/w) on their forearms. The measurement of basic skin parameters (stratum corneum hydration and epidermal barrier function) was performed once a week. The in vivo antiinflammatory activity based on the methyl nicotinate model of microinflammation in human skin was evaluated after four weeks application of tested formulations. In vivo tests formulations containing 5% of Centella asiatica extract showed the best efficacy in improving skin moisture by increase of skin surface hydration state and decrease in transepidermal water loss as well as exhibited antiinflammatory properties based on the methyl nicotinate model of microinflammation in human skin. Comparative tests conducted by corneometer, tewameter and chromameter showed that cosmetic formulations containing Centella asiatica extract have the moisturizing and antiinflammatory properties. PMID:27168678

3D porous polyurethanes featured by different mechanical properties: Characterization and interaction with skeletal muscle cells.

PubMed

Vannozzi, Lorenzo; Ricotti, Leonardo; Santaniello, Tommaso; Terencio, Tercio; Oropesa-Nunez, Reinier; Canale, Claudio; Borghi, Francesca; Menciassi, Arianna; Lenardi, Cristina; Gerges, Irini

2017-11-01

The fabrication of biomaterials for interaction with muscle cells has attracted significant interest in the last decades. However, 3D porous scaffolds featured by a relatively low stiffness (almost matching the natural muscle one) and highly stable in response to cyclic loadings are not available at present, in this context. This work describes 3D polyurethane-based porous scaffolds featured by different mechanical properties. Biomaterial stiffness was finely tuned by varying the cross-linking degree of the starting foam. Compression tests revealed, for the softest material formulation, stiffness values close to the ones possessed by natural skeletal muscles. The materials were also characterized in terms of local nanoindenting, rheometric properties and long-term stability through cyclic compressions, in a strain range reflecting the contraction extent of natural muscles. Preliminary in vitro tests revealed a preferential adhesion of C2C12 skeletal muscle cells over the softer, rougher and more porous structures. All the material formulations showed low cytotoxicity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Questions concerning the potential impact of glyphosate-based herbicides on amphibians.

PubMed

Wagner, Norman; Reichenbecher, Wolfram; Teichmann, Hanka; Tappeser, Beatrix; Lötters, Stefan

2013-08-01

Use of glyphosate-based herbicides is increasing worldwide. The authors review the available data related to potential impacts of these herbicides on amphibians and conduct a qualitative meta-analysis. Because little is known about environmental concentrations of glyphosate in amphibian habitats and virtually nothing is known about environmental concentrations of the substances added to the herbicide formulations that mainly contribute to adverse effects, glyphosate levels can only be seen as approximations for contamination with glyphosate-based herbicides. The impact on amphibians depends on the herbicide formulation, with different sensitivity of taxa and life stages. Effects on development of larvae apparently are the most sensitive endpoints to study. As with other contaminants, costressors mainly increase adverse effects. If and how glyphosate-based herbicides and other pesticides contribute to amphibian decline is not answerable yet due to missing data on how natural populations are affected. Amphibian risk assessment can only be conducted case-specifically, with consideration of the particular herbicide formulation. The authors recommend better monitoring of both amphibian populations and contamination of habitats with glyphosate-based herbicides, not just glyphosate, and suggest including amphibians in standardized test batteries to study at least dermal administration. Copyright © 2013 SETAC.

Developments in variational methods for high performance plate and shell elements

NASA Technical Reports Server (NTRS)

Felippa, Carlos A.; Militello, Carmelo

1991-01-01

High performance elements are simple finite elements constructed to deliver engineering accuracy with coarse arbitrary grids. This is part of a series on the variational foundations of high-performance elements, with emphasis on plate and shell elements constructed with the free formulation (FF) and assumed natural strain (ANS) methods. Parameterized variational principles are studied that provide a common foundation for the FF and ANS methods, as well as for a combination of both. From this unified formulation a variant of the ANS formulation, called the assumed natural deviatoric strain (ANDES) formulation, emerges as an important special case. The first ANDES element, a high-performance 9 degrees of freedom triangular Kirchhoff plate bending element, is briefly described to illustrate the use of the new formulation.

Bayesian Inference of Natural Rankings in Incomplete Competition Networks

PubMed Central

Park, Juyong; Yook, Soon-Hyung

2014-01-01

Competition between a complex system's constituents and a corresponding reward mechanism based on it have profound influence on the functioning, stability, and evolution of the system. But determining the dominance hierarchy or ranking among the constituent parts from the strongest to the weakest – essential in determining reward and penalty – is frequently an ambiguous task due to the incomplete (partially filled) nature of competition networks. Here we introduce the “Natural Ranking,” an unambiguous ranking method applicable to a round robin tournament, and formulate an analytical model based on the Bayesian formula for inferring the expected mean and error of the natural ranking of nodes from an incomplete network. We investigate its potential and uses in resolving important issues of ranking by applying it to real-world competition networks. PMID:25163528

Bayesian Inference of Natural Rankings in Incomplete Competition Networks

NASA Astrophysics Data System (ADS)

Park, Juyong; Yook, Soon-Hyung

2014-08-01

Competition between a complex system's constituents and a corresponding reward mechanism based on it have profound influence on the functioning, stability, and evolution of the system. But determining the dominance hierarchy or ranking among the constituent parts from the strongest to the weakest - essential in determining reward and penalty - is frequently an ambiguous task due to the incomplete (partially filled) nature of competition networks. Here we introduce the ``Natural Ranking,'' an unambiguous ranking method applicable to a round robin tournament, and formulate an analytical model based on the Bayesian formula for inferring the expected mean and error of the natural ranking of nodes from an incomplete network. We investigate its potential and uses in resolving important issues of ranking by applying it to real-world competition networks.

Single immunization with a suboptimal antigen dose encapsulated into polyanhydride microparticles promotes high titer and avid antibody responses

USDA-ARS?s Scientific Manuscript database

Microparticle adjuvants based on biodegradable polyanhydrides were used to provide controlled delivery of a model antigen, ovalbumin (Ova), to mice. Ova was encapsulated into two different polyanhydride microparticle formulations to evaluate the influence of polymer chemistry on the nature and magn...

What is urban environmental stewardship? Constructing a practitioner-derived framework

Treesearch

M. Romolini; W. Brinkley; K.L. Wolf

2012-01-01

Agencies and organizations deploy various strategies in response to environmental challenges, including the formulation of policy, programs, and regulations. Citizen-based environmental stewardship is increasingly seen as an innovative and important approach to improving and conserving landscape health. A new research focus on the stewardship of urban natural resources...

AQUEOUS REDUCTION OF HG2+ TO HG0 BY HO2 IN THE CMAQ-MODEL

EPA Science Inventory

Numerical models of atmospheric mercury are formulated based on the current understanding of mercury chemistry in air and in atmospheric water. Recent evidence that significant reduction of Hg2+ by reaction with HO2 may not actually occur in natural atmospheric water has obviou...

Pinhão starch and coat extract as new natural cosmetic ingredients: Topical formulation stability and sensory analysis.

PubMed

Daudt, Renata Moschini; Back, Patrícia Inês; Cardozo, Nilo Sérgio Medeiros; Marczak, Ligia Damasceno Ferreira; Külkamp-Guerreiro, Irene Clemes

2015-12-10

The objective of this study was to use pinhão derivatives, starch and coat extract, as new natural ingredients to develop cosmetic formulations. Two types of formulation, gel and emulgel, and their controls were developed. The formulations were characterized by stability studies using thermal stress. The parameters analyzed were resistance to centrifugation, pH, spreadability, rheology, content of phenolic compounds and antioxidant activity. Sensory analysis was also performed to verify the acceptability of the ingredients to potential consumers. The pH was kept the same after heating/freezing cycles for all formulations, and the formulations showed stability by resistance to centrifugation. The formulations did not induce any skin irritation or cutaneous pH alteration. The pinhão starch addition improved spreadability stability and increased viscosity when compared with control formulations. The pinhão coat extract used in these formulations is a good source of phenolic compounds and antioxidant activity. Moreover, sensory analysis indicates that the emulgel formulation is the best vehicle for adding pinhão starch and pinhão coat extract. Copyright © 2015 Elsevier Ltd. All rights reserved.

Spline-based Rayleigh-Ritz methods for the approximation of the natural modes of vibration for flexible beams with tip bodies

NASA Technical Reports Server (NTRS)

Rosen, I. G.

1985-01-01

Rayleigh-Ritz methods for the approximation of the natural modes for a class of vibration problems involving flexible beams with tip bodies using subspaces of piecewise polynomial spline functions are developed. An abstract operator theoretic formulation of the eigenvalue problem is derived and spectral properties investigated. The existing theory for spline-based Rayleigh-Ritz methods applied to elliptic differential operators and the approximation properties of interpolatory splines are useed to argue convergence and establish rates of convergence. An example and numerical results are discussed.

Quantum Jarzynski equality of measurement-based work extraction

NASA Astrophysics Data System (ADS)

Morikuni, Yohei; Tajima, Hiroyasu; Hatano, Naomichi

2017-03-01

Many studies of quantum-size heat engines assume that the dynamics of an internal system is unitary and that the extracted work is equal to the energy loss of the internal system. Both assumptions, however, should be under scrutiny. In the present paper, we analyze quantum-scale heat engines, employing the measurement-based formulation of the work extraction recently introduced by Hayashi and Tajima [M. Hayashi and H. Tajima, arXiv:1504.06150]. We first demonstrate the inappropriateness of the unitary time evolution of the internal system (namely, the first assumption above) using a simple two-level system; we show that the variance of the energy transferred to an external system diverges when the dynamics of the internal system is approximated to a unitary time evolution. Second, we derive the quantum Jarzynski equality based on the formulation of Hayashi and Tajima as a relation for the work measured by an external macroscopic apparatus. The right-hand side of the equality reduces to unity for "natural" cyclic processes but fluctuates wildly for noncyclic ones, exceeding unity often. This fluctuation should be detectable in experiments and provide evidence for the present formulation.

Quantum Jarzynski equality of measurement-based work extraction.

PubMed

Morikuni, Yohei; Tajima, Hiroyasu; Hatano, Naomichi

2017-03-01

Many studies of quantum-size heat engines assume that the dynamics of an internal system is unitary and that the extracted work is equal to the energy loss of the internal system. Both assumptions, however, should be under scrutiny. In the present paper, we analyze quantum-scale heat engines, employing the measurement-based formulation of the work extraction recently introduced by Hayashi and Tajima [M. Hayashi and H. Tajima, arXiv:1504.06150]. We first demonstrate the inappropriateness of the unitary time evolution of the internal system (namely, the first assumption above) using a simple two-level system; we show that the variance of the energy transferred to an external system diverges when the dynamics of the internal system is approximated to a unitary time evolution. Second, we derive the quantum Jarzynski equality based on the formulation of Hayashi and Tajima as a relation for the work measured by an external macroscopic apparatus. The right-hand side of the equality reduces to unity for "natural" cyclic processes but fluctuates wildly for noncyclic ones, exceeding unity often. This fluctuation should be detectable in experiments and provide evidence for the present formulation.

Formulation and Evaluation of Mouth Disintegrating Tablets of Atenolol and Atorvastatin

PubMed Central

Sarfraz, R. M.; Khan, H. U.; Mahmood, A.; Ahmad, M.; Maheen, S.; Sher, M.

2015-01-01

In this study, mouth-disintegrating tablets of atenolol and atorvastatin combination were formulated using superdisintegrants to impart fast disintegration. Fifteen formulations were prepared based on different concentrations of two superdisintegrants, croscarmellose sodium and Kyron-T134. Three different techniques such as direct compression, effervescent and sublimation were used to study the effect of manufacturing processes, nature and concentration of superdisintegrants on various features of these tablets. Five formulations were made using each method. Precompression studies like bulk density, tapped density, angle of repose, Carr's compressibility index, Hausner's ratio and compatibility studies such as Fourier transform infrared spectroscopy and differential scanning calorimetry were performed. Various features such as hardness, thickness, diameter, weight variation, friability, disintegration time, dissolution studies, wetting time, wetting volume, water absorption ratio, modified disintegration, uniformity of contents and stability were evaluated. Finally results were statistically analyzed by the application of one way ANOVA test. Formulation F13 containing Kyron-T134 (6%) and croscarmellose sodium (2%) was found to be the best among all fifteen formulations prepared in all aspects evaluated. Sublimation method is found to be the best among three methods of preparation used. PMID:25767322

XFEM modeling of hydraulic fracture in porous rocks with natural fractures

NASA Astrophysics Data System (ADS)

Wang, Tao; Liu, ZhanLi; Zeng, QingLei; Gao, Yue; Zhuang, Zhuo

2017-08-01

Hydraulic fracture (HF) in porous rocks is a complex multi-physics coupling process which involves fluid flow, diffusion and solid deformation. In this paper, the extended finite element method (XFEM) coupling with Biot theory is developed to study the HF in permeable rocks with natural fractures (NFs). In the recent XFEM based computational HF models, the fluid flow in fractures and interstitials of the porous media are mostly solved separately, which brings difficulties in dealing with complex fracture morphology. In our new model the fluid flow is solved in a unified framework by considering the fractures as a kind of special porous media and introducing Poiseuille-type flow inside them instead of Darcy-type flow. The most advantage is that it is very convenient to deal with fluid flow inside the complex fracture network, which is important in shale gas extraction. The weak formulation for the new coupled model is derived based on virtual work principle, which includes the XFEM formulation for multiple fractures and fractures intersection in porous media and finite element formulation for the unified fluid flow. Then the plane strain Kristianovic-Geertsma-de Klerk (KGD) model and the fluid flow inside the fracture network are simulated to validate the accuracy and applicability of this method. The numerical results show that large injection rate, low rock permeability and isotropic in-situ stresses tend to lead to a more uniform and productive fracture network.

Bio-based topical system for enhanced salicylic acid delivery: preparation and performance of gels.

PubMed

Langasco, Rita; Spada, Gianpiera; Tanriverdi, Sakine Tuncay; Rassu, Giovanna; Giunchedi, Paolo; Özer, Özgen; Gavini, Elisabetta

2016-08-01

New salicylic acid (SA)-loaded gels were developed using excipients made from renewable materials, and our goal was to improve drug permeation in the topical treatment of acne vulgaris. We studied the preparation parameters to obtain suitable gel formulations. Only naturally occurring polymers were used as gelling agents. Two hydrogels and three lipogels were selected and characterized in terms of drug loading, pH, viability cells, rheology, mechanical properties and in vitro permeation; these hydrogels and lipogels were compared with the traditional ointment. We also evaluated skin parameters before and after gel application. The formulations that we studied are non-Newtonian fluids; they have high drug loading and suitable mechanical properties. Lipogels exhibit a slower and more linear in vitro permeation profile compared with hydrogels. The different vehicles that we used affected drug permeation and improve patient compliance. Cytotoxicity studies suggest that all of the formulations are non-toxic. Lipogels demonstrate appropriate technological features and improved performance compared with the traditional ointment with regard to their composition. Lipogels may represent a new bio-based topical system for SA delivery. The use of 'green' excipients leads to 'skin-friendly' formulations that are able to satisfy environmental safety. © 2016 Royal Pharmaceutical Society.

Comparative Oral Absorption of Curcumin in a Natural Turmeric Matrix with Two Other Curcumin Formulations: An Open-label Parallel-arm Study.

PubMed

Gopi, Sreeraj; Jacob, Joby; Varma, Karthik; Jude, Shintu; Amalraj, Augustine; Arundhathy, C A; George, Robin; Sreeraj, T R; Divya, C; Kunnumakkara, Ajaikumar B; Stohs, Sidney J

2017-12-01

Curcuminoids are the major bioactive molecules in turmeric, and poor bioavailability deters them from being the major components of many health and wellness applications. This study was conducted to assess the bioavailability of a completely natural turmeric matrix formulation (CNTMF) and compare its bioavailability with two other commercially available formulations, namely, curcumin with volatile oil (volatile oil formulation) and curcumin with phospholipids and cellulose (phospholipid formulation) in healthy human adult male subjects (15 each group) under fasting conditions. Each formulation was administrated orally as a single 500-mg dose in capsule form, and blood samples were analyzed by liquid chromatography mass spectrometry at various time intervals up to 24 h. The ingestion of the CNTMF was very well absorbed and resulted in a mean curcuminoids plasma C max of 170.14 ng/mL (T max  = 4 h) compared with 47.54 ng/mL and 69.63 ng/mL for the volatile oil (T max  = 3 h) and phospholipid (T max  = 2.25 h) formulations, respectively. The extent of absorption of total curcuminoids in the blood for the CNTMF was 6× greater than volatile oil formulation and 5× greater than phospholipids formulation. The results of this study indicate that curcumin in a natural turmeric matrix exhibited greater bioavailability than the two comparator products. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

A new graph-based method for pairwise global network alignment

PubMed Central

Klau, Gunnar W

2009-01-01

Background In addition to component-based comparative approaches, network alignments provide the means to study conserved network topology such as common pathways and more complex network motifs. Yet, unlike in classical sequence alignment, the comparison of networks becomes computationally more challenging, as most meaningful assumptions instantly lead to NP-hard problems. Most previous algorithmic work on network alignments is heuristic in nature. Results We introduce the graph-based maximum structural matching formulation for pairwise global network alignment. We relate the formulation to previous work and prove NP-hardness of the problem. Based on the new formulation we build upon recent results in computational structural biology and present a novel Lagrangian relaxation approach that, in combination with a branch-and-bound method, computes provably optimal network alignments. The Lagrangian algorithm alone is a powerful heuristic method, which produces solutions that are often near-optimal and – unlike those computed by pure heuristics – come with a quality guarantee. Conclusion Computational experiments on the alignment of protein-protein interaction networks and on the classification of metabolic subnetworks demonstrate that the new method is reasonably fast and has advantages over pure heuristics. Our software tool is freely available as part of the LISA library. PMID:19208162

Natural lipids-based NLC containing lidocaine: from pre-formulation to in vivo studies.

PubMed

Ribeiro, Lígia N M; Breitkreitz, Márcia C; Guilherme, Viviane A; da Silva, Gustavo H R; Couto, Verônica M; Castro, Simone R; de Paula, Bárbara O; Machado, Daisy; de Paula, Eneida

2017-08-30

In a nanotechnological approach we have investigated the use of natural lipids in the preparation of nanostructured lipid carriers (NLC). Three different NLC composed of copaiba oil and beeswax, sweet almond oil and shea butter, and sesame oil and cocoa butter as structural matrices were optimized using factorial analysis; Pluronic® 68 and lidocaine (LDC) were used as the colloidal stabilizer and model encapsulated drug, respectively. The optimal formulations were characterized by different techniques (IR-ATR, DSC, and TEM), and their safety and efficacy were also tested. These nanocarriers were able to upload high amounts of the anesthetic with a sustained in vitro release profile for 24h. The physicochemical stability in terms of size (nm), PDI, zeta potential (mV), pH, nanoparticle concentration (particles/mL), and visual inspection was followed during 12months of storage at 25°C. The formulations exhibited excellent structural properties and stability. They proved to be nontoxic in vitro (cell viability tests with Balb/c 3T3 fibroblasts) and significantly improved the in vivo effects of LDC, over the heart rate of zebra fish larvae and in the blockage of sciatic nerve in mice. The results from this study support that the proper combination of natural excipients is promising in DDS, taking advantage of the biocompatibility, low cost, and diversity of lipids. Copyright © 2017 Elsevier B.V. All rights reserved.

Formulation and in vitro release evaluation of newly synthesized palm kernel oil esters-based nanoemulsion delivery system for 30% ethanolic dried extract derived from local Phyllanthus urinaria for skin antiaging.

PubMed

Mahdi, Elrashid Saleh; Noor, Azmin Mohd; Sakeena, Mohamed Hameem; Abdullah, Ghassan Z; Abdulkarim, Muthanna F; Sattar, Munavvar Abdul

2011-01-01

Recently there has been a remarkable surge of interest about natural products and their applications in the cosmetic industry. Topical delivery of antioxidants from natural sources is one of the approaches used to reverse signs of skin aging. The aim of this research was to develop a nanoemulsion cream for topical delivery of 30% ethanolic extract derived from local Phyllanthus urinaria (P. urinaria) for skin antiaging. Palm kernel oil esters (PKOEs)-based nanoemulsions were loaded with P. urinaria extract using a spontaneous method and characterized with respect to particle size, zeta potential, and rheological properties. The release profile of the extract was evaluated using in vitro Franz diffusion cells from an artificial membrane and the antioxidant activity of the extract released was evaluated using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method. Formulation F12 consisted of wt/wt, 0.05% P. urinaria extract, 1% cetyl alcohol, 0.5% glyceryl monostearate, 12% PKOEs, and 27% Tween 80/Span 80 (9/1) with a hydrophilic lipophilic balance of 13.9, and a 59.5% phosphate buffer system at pH 7.4. Formulation F36 was comprised of 0.05% P. urinaria extract, 1% cetyl alcohol, 1% glyceryl monostearate, 14% PKOEs, 28% Tween 80/Span 80 (9/1) with a hydrophilic lipophilic balance of 13.9, and 56% phosphate buffer system at pH 7.4 with shear thinning and thixotropy. The droplet size of F12 and F36 was 30.74 nm and 35.71 nm, respectively, and their nanosizes were confirmed by transmission electron microscopy images. Thereafter, 51.30% and 51.02% of the loaded extract was released from F12 and F36 through an artificial cellulose membrane, scavenging 29.89% and 30.05% of DPPH radical activity, respectively. The P. urinaria extract was successfully incorporated into a PKOEs-based nanoemulsion delivery system. In vitro release of the extract from the formulations showed DPPH radical scavenging activity. These formulations can neutralize reactive oxygen species and counteract oxidative injury induced by ultraviolet radiation and thereby ameliorate skin aging.

The first ANDES elements: 9-DOF plate bending triangles

NASA Technical Reports Server (NTRS)

Militello, Carmelo; Felippa, Carlos A.

1991-01-01

New elements are derived to validate and assess the assumed natural deviatoric strain (ANDES) formulation. This is a brand new variant of the assumed natural strain (ANS) formulation of finite elements, which has recently attracted attention as an effective method for constructing high-performance elements for linear and nonlinear analysis. The ANDES formulation is based on an extended parametrized variational principle developed in recent publications. The key concept is that only the deviatoric part of the strains is assumed over the element whereas the mean strain part is discarded in favor of a constant stress assumption. Unlike conventional ANS elements, ANDES elements satisfy the individual element test (a stringent form of the patch test) a priori while retaining the favorable distortion-insensitivity properties of ANS elements. The first application of this formulation is the development of several Kirchhoff plate bending triangular elements with the standard nine degrees of freedom. Linear curvature variations are sampled along the three sides with the corners as gage reading points. These sample values are interpolated over the triangle using three schemes. Two schemes merge back to conventional ANS elements, one being identical to the Discrete Kirchhoff Triangle (DKT), whereas the third one produces two new ANDES elements. Numerical experiments indicate that one of the ANDES element is relatively insensitive to distortion compared to previously derived high-performance plate-bending elements, while retaining accuracy for nondistorted elements.

Biopolyester-based systems containing naturally occurring compounds with enhanced thermo-oxidative stability.

PubMed

Arrigo, Rossella; Morici, Elisabetta; Dintcheva, Nadka Tzankova

2016-11-02

This work presents a sustainable approach for the stabilization of polylactic acid (PLA) against thermo-oxidative aging. Naturally occurring phenolic and polyphenolic compounds, such as ferulic acid (FerAc), vanillic acid (VanAc), quercetin (Querc) and vitamin E (VitE), were introduced into PLA. The preliminary characterization of the systems formulated containing different amounts of natural stabilizers showed that all compounds used acted as plasticizers, leading to a decrease in rheological functions with respect to neat PLA, without significantly modifying the crystallinity of the raw material. The study of the thermo-oxidative behavior of neat PLA and PLA/natural compound systems, performed by spectrometric and thermal analyses, indicated that all stabilizers considered were able to exert a remarkable antioxidant action against thermo-oxidative phenomena. All natural compounds considered are thus proposed as ecofriendly stabilizers, to get fully bio-based polymer systems with enhanced thermo-oxidative stability, suitable for biomedical applications.

Formulation effects on the mechanical and release properties of metronidazole suppositories.

PubMed

Adegboye, T A; Itiola, O A

2003-09-01

A study of the effects of Tween 20 and Tween 80 non-ionic surfactants, and witepsol H15 and polyethylene glycol (PEG) 2850 bases, on the mechanical and release properties of metronidazole suppositories was made. Mechanical strength was assessed by breaking strength values F. The values of F increased with increase in concentration of surfactant. The values of F for formulations containing Tween 20 were higher than those obtained for formulations containing Tween 80. Witepsol bases gave higher values of F than corresponding PEG bases. Release characteristics were assessed by the time for 80% drug release (t80), values of dissolution rate constants, k1 and k2 and the time of intersection, t1. The values of t80 decreased while those of k1 and k2 increased with increase in surfactant concentration. The values of t80 were lower, while those of k1 and k2 were higher, for formulations containing Tween 20 than for those formulations containing Tween 80. Witepsol bases gave lower t80 values and higher k1 and k2 values than their corresponding PEG bases. The concentration of surfactant, C, had the largest individual effect on the mechanical and release parameters while the nature of surfactant, S, had the lowest. The ranking for the individual effects of the variables on F and k1 was C > N > S, on t80 and k2 was C > N approximately = S, was on t1 was C = N = S. The interactions between S and C were largest for F, t80 and k2, and lowest for k1 and t1. The ranking of the interaction effects of the variables on F and k2 was S-C > N-C > N-S, on t80 was S-C > N-S approximately = N-C, on k1 was N-C > N-S > S-C, and on t1 was N-S = N-C > S-C. The results suggest that the individual and interaction effects of formulation variables would provide useful guides in optimizing metronidazole suppository formulations.

Utilization of Chinese tallow tree and bagasse for medium density fiberboard

Treesearch

Sangyeob Lee; Todd F. Shupe; Chung Y. Hse

2004-01-01

The objective of this research was to investigate various adhesive systems and determine the best composite formulation for selected mechanical and physical properties of medium density fiberboard (MDF) made from wood and bagasse fibers. This study investigated opportunities ofbiomass utilization for natural fiber-based composites from agricultural (bagasse) and...

Photochemistry of Fe(Iii)-Carboxylates in Polysaccharide-Based Materials with Tunable Mechanical Properties

NASA Astrophysics Data System (ADS)

Giammanco, Giuseppe E.

We present the formulation and study of light-responsive materials based on carboxylate-containing polysaccharides. The functional groups in these natural polymers allow for strong interactions with transition metal ions such as Fe(III). The known photochemistry of hydroxycarboxylic acids in natural waters inspired us in exploring the visible light induced photochemistry of the carboxylates in these polysaccharides when coordinated to Fe(III) ions. Described in this dissertation are the design and characterization of the Fe(III)-polysaccharide materials, specifically the mechanistic aspects of the photochemistry and the effects that these reactions have on the structure of the polymer materials. We present a study of the quantitative photochemistry of different polysaccharide systems, where the presence of uronic acids was important for the photoreaction to take place. Alginate (Alg), pectate (Pec), hyaluronic acid (Hya), xanthan gum (Xan), and a polysaccharide extracted from the Noni fruit (NoniPs), were among the natural uronic acid-containing polysaccharide (UCPS) systems we analyzed. Potato starch, lacking of uronate groups, did not present any photochemistry in the presence of Fe(III); however, we were able to induce a photochemical response in this polysaccharide upon chemical manipulation of its functional groups. Important structure-function relationships were drawn from this study. The uronate moiety present in these polysaccharides is then envisioned as a tool to induce response to light in a variety of materials. Following this approach, we report the formulation of materials for controlled drug release, able to encapsulate and release different drug models only upon illumination with visible light. Furthermore, hybrid hydrogels were prepared from UPCS and non-responsive polymers. Different properties of these materials could be tuned by controlling the irradiation time, intensity and location. These hybrid gels were evaluated as scaffolds for tissue engineering showing great promise, as changes in the behavior of the growing cells were observed as a result of the photochemical treatment of the material. We present these natural and readily available, polysaccharide-based, metal-coordination materials as convenient building blocks in the formulation of new stimuli responsive materials. The photochemical methods developed here can be used as convenient tools for creating advanced materials with tailored patterns and gradients of mechanical properties.

Formulation of sage essential oil (Salvia officinalis, L.) monoterpenes into chitosan hydrogels and permeation study with GC-MS analysis.

PubMed

Kodadová, Alexandra; Vitková, Zuzana; Herdová, Petra; Ťažký, Anton; Oremusová, Jarmila; Grančai, Daniel; Mikuš, Peter

2015-01-01

This study deals with the formulation of natural drugs into hydrogels. For the first time, compounds from the sage essential oil were formulated into chitosan hydrogels. A sample preparation procedure for hydrophobic volatile analytes present in a hydrophilic water matrix along with an analytical method based on the gas chromatography coupled with the mass spectrometry (GC-MS) was developed and applied for the evaluation of the identity and quantity of essential oil components in the hydrogels and saline samples. The experimental results revealed that the chitosan hydrogels are suitable for the formulation of sage essential oil. The monoterpene release can be effectively controlled by both chitosan and caffeine concentration in the hydrogels. Permeation experiment, based on a hydrogel with the optimized composition [3.5% (w/w) sage essential oil, 2.0% (w/w) caffeine, 2.5% (w/w) chitosan and 0.1% (w/w) Tween-80] in donor compartment, saline solution in acceptor compartment, and semi-permeable cellophane membrane, demonstrated the useful permeation selectivity. Here, (according to lipophilicity) an enhanced permeation of the bicyclic monoterpenes with antiflogistic and antiseptic properties (eucalyptol, camphor and borneol) and, at the same time, suppressed permeation of toxic thujone (not exceeding its permitted applicable concentration) was observed. These properties highlight the pharmaceutical importance of the developed chitosan hydrogel formulating sage essential oil in the dermal applications.

Transport of reacting solutes in porous media: Relation between mathematical nature of problem formulation and chemical nature of reactions

USGS Publications Warehouse

Rubin, Jacob

1983-01-01

Examples involving six broad reaction classes show that the nature of transport-affecting chemistry may have a profound effect on the mathematical character of solute transport problem formulation. Substantive mathematical diversity among such formulations is brought about principally by reaction properties that determine whether (1) the reaction can be regarded as being controlled by local chemical equilibria or whether it must be considered as being controlled by kinetics, (2) the reaction is homogeneous or heterogeneous, (3) the reaction is a surface reaction (adsorption, ion exchange) or one of the reactions of classical chemistry (e.g., precipitation, dissolution, oxidation, reduction, complex formation). These properties, as well as the choice of means to describe them, stipulate, for instance, (1) the type of chemical entities for which a formulation's basic, mass-balance equations should be written; (2) the nature of mathematical transformations needed to change the problem's basic equations into operational ones. These and other influences determine such mathematical features of problem formulations as the nature of the operational transport-equation system (e.g., whether it involves algebraic, partial-differential, or integro-partial-differential simultaneous equations), the type of nonlinearities of such a system, and the character of the boundaries (e.g., whether they are stationary or moving). Exploration of the reasons for the dependence of transport mathematics on transport chemistry suggests that many results of this dependence stem from the basic properties of the reactions' chemical-relation (i.e., equilibrium or rate) equations.

Emission factors for fugitive dust from bulldozers working on a coal pile.

PubMed

Mueller, Stephen F; Mallard, Jonathan W; Mao, Qi; Shaw, Stephanie L

2015-01-01

A study of a Powder River Basin (PRB) coal pile found that fugitive emissions from natural and human activity each produced similar levels of downwind fine + coarse (i.e., smaller than 10 µm, or PM10) particle mass concentrations. Natural impacts were statistically removed from downwind measurements to estimate emission factor Ev for bulldozers working on the pile. The Ev determined here was similar in magnitude to emission factors (EFs) computed using a U.S. Environmental Protection Agency (EPA) formulation for unpaved surfaces at industrial sites, even though the latter was not based on data for coal piles. EF formulations from this study and those in the EPA guidance yield values of similar magnitude but differ in the variables used to compute Ev variations. EPA studies included effects of surface silt fraction and vehicle weight, while the present study captured the influence of coal moisture. Our data indicate that the relationship between PRB coal fugitive dust Ev (expressed as mass of PM10 emitted per minute of bulldozer operation) and coal moisture content Mc (in percent) at the study site is best expressed as Ev =10(f(Mc())) where f(Mc) is a function of moisture. This function was determined by statistical regression between log10(Ev) and Mc where both Ev and Mc are expressed as daily averages of observations based on 289 hours sampled during 44 days from late June through mid-November of 2012. A methodology is described that estimates Mc based on available meteorological data (precipitation amount and solar radiation flux). An example is given of computed variations in daily Ev for an entire year. This illustrates the sensitivity of the daily average particulate EF to meteorological variability at one location. Finally, a method is suggested for combining the moisture-sensitive formulation for Ev with the EPA formulation to accommodate a larger number of independent variables that influence fugitive emissions.

Automatic Query Formulations in Information Retrieval.

ERIC Educational Resources Information Center

Salton, G.; And Others

1983-01-01

Introduces methods designed to reduce role of search intermediaries by generating Boolean search formulations automatically using term frequency considerations from natural language statements provided by system patrons. Experimental results are supplied and methods are described for applying automatic query formulation process in practice.…

Recent Advances in Hydrogel-Based Drug Delivery for Melanoma Cancer Therapy: A Mini Review

PubMed Central

Elupula, Ravinder

2017-01-01

The purpose of this study is to describe some of the latest advances in using hydrogels for cancer melanoma therapy. Hydrogel formulations of polymeric material from natural or synthetic sources combined with therapeutic agents have gained great attention in the recent years for treating various maladies. These formulations can be categorized according to the strategies that induce cancer cell death in melanoma. First of all, we should note that these formulations can only play a supporting role that releases bioactive agents against cancer cells rather than the main role. This strategy involves delivering the drug via transdermal pathways, resulting in the death of cancerous cells. Another strategy utilizes magnetic gel composites to combat melanoma via hyperthermia therapy. This review discusses both transdermal and hyperthermia therapies and the recent advances that have occurred in the field. PMID:28852576

Chemometric formulation of bacterial consortium-AVS for improved decolorization of resonance-stabilized and heteropolyaromatic dyes.

PubMed

Kumar, Madhava Anil; Kumar, Vaidyanathan Vinoth; Premkumar, Manickam Periyaraman; Baskaralingam, Palanichamy; Thiruvengadaravi, Kadathur Varathachary; Dhanasekaran, Anuradha; Sivanesan, Subramanian

2012-11-01

A bacterial consortium-AVS, consisting of Pseudomonas desmolyticum NCIM 2112, Kocuria rosea MTCC 1532 and Micrococcus glutamicus NCIM 2168 was formulated chemometrically, using the mixture design matrix based on the design of experiments methodology. The formulated consortium-AVS decolorized acid blue 15 and methylene blue with a higher average decolorization rate, which is more rapid than that of the pure cultures. The UV-vis spectrophotometric, Fourier transform infra red spectrophotometric and high performance liquid chromatographic analysis confirm that the decolorization was due to biodegradation by oxido-reductive enzymes, produced by the consortium-AVS. The toxicological assessment of plant growth parameters and the chlorophyll pigment concentrations of Phaseolus mungo and Triticum aestivum seedlings revealed the reduced toxic nature of the biodegraded products. Copyright © 2012 Elsevier Ltd. All rights reserved.

Characterization and Testing of Amidoxime-Based Adsorbent Materials to Extract Uranium from Natural Seawater

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

Kuo, Li-Jung; Janke, Christopher J.; Wood, Jordana R.

Extraction of uranium (U) from seawater for use as a nuclear fuel is a significant challenge due to the low concentration of U in seawater (~3.3 ppb) and difficulties to selectively extract U from the background of major and trace elements in seawater. The Pacific Northwest National Laboratory (PNNL)’s Marine Sciences Laboratory (MSL) has been serving as a marine test site for determining performance characteristics (adsorption capacity, adsorption kinetics, and selectivity) of novel amidoxime-based polymeric adsorbents developed at Oak Ridge National Laboratory (ORNL) under natural seawater exposure conditions. This manuscript describes the performance of three formulations (38H, AF1, AI8) ofmore » amidoxime-based polymeric adsorbents produced at ORNL in MSL’s ambient seawater testing facility. The adsorbents were produced in two forms, fibrous material (40-100 mg samples) and braided material (5-10 g samples), and exposed to natural seawater using flow-through columns and recirculating flumes. All three formulations demonstrated high 56 day uranium adsorption capacity (>3 g U/kg adsorbent). The AF1 formulation had the best uranium adsorption performance, with a 56 day capacity of 3.9 g U/ kg adsorbent, a saturation capacity of 5.4 g U/kg adsorbent, and ~25 days half-saturation time. The two exposure methods, flowthrough columns and flumes, were demonstrated to produce similar performance results, providing confidence that the test methods were reliable, that scaling up from 10’s of mg quantities of exposure in flow-through columns to gram quantities in flumes produced similar results, and confirm that the manufacturing process produces a homogeneous adsorbent. Adsorption kinetics appear to be element specific, with half-saturation times ranging from minutes for the major cations in seawater, to 8-10 weeks for V and Fe. Reducing the exposure time provides a potential pathway to improve the adsorption capacity of U by reducing the V/U ratio on the adsorbent.« less

Characterization and testing of amidoxime-based adsorbent materials to extract uranium from natural seawater

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

Kuo, Li-Jung; Janke, Christopher James; Wood, Jordana

Extraction of uranium (U) from seawater for use as a nuclear fuel is a significant challenge due to the low concentration of U in seawater (~3.3 ppb) and difficulties to selectively extract U from the background of major and trace elements in seawater. The Pacific Northwest National Laboratory (PNNL) s Marine Sciences Laboratory (MSL) has been serving as a marine test site for determining performance characteristics (adsorption capacity, adsorption kinetics, and selectivity) of novel amidoxime-based polymeric adsorbents developed at Oak Ridge National Laboratory (ORNL) under natural seawater exposure conditions. This report describes the performance of three formulations (38H, AF1, AI8)more » of amidoxime-based polymeric adsorbent produced at ORNL in MSL s ambient seawater testing facility. The adsorbents were produced in two forms, fibrous material (40-100 mg samples) and braided material (5-10 g samples), exposed to natural seawater using flow-through columns and recirculating flumes. All three formulations demonstrated high 56 day uranium adsorption capacity (>3 gU/kg adsorbent). The AF1 formulation had the best uranium adsorption performance, with 56-day capacity of 3.9 g U/kg adsorbent, saturation capacity of 5.4 g U/kg adsorbent, and ~25 days half-saturation time. The two exposure methods, flow-through columns and flumes were demonstrated to produce similar performance results, providing confidence that the test methods were reliable, that scaling up from 10 s of mg quantities of exposure in flow-through columns to gram quantities in flumes produced similar results, and that the manufacturing process produces a homogenous adsorbent. Adsorption kinetics appear to be element specific, with half-saturation times ranging from minutes for the major cations in seawater to 8-10weeks for V and Fe. Reducing the exposure time provides a potential pathway to improve the adsorption capacity of U by reducing the V/U ratio on the adsorbent.« less

Characterization and testing of amidoxime-based adsorbent materials to extract uranium from natural seawater

DOE PAGES

Kuo, Li-Jung; Janke, Christopher James; Wood, Jordana; ...

2015-11-19

Extraction of uranium (U) from seawater for use as a nuclear fuel is a significant challenge due to the low concentration of U in seawater (~3.3 ppb) and difficulties to selectively extract U from the background of major and trace elements in seawater. The Pacific Northwest National Laboratory (PNNL) s Marine Sciences Laboratory (MSL) has been serving as a marine test site for determining performance characteristics (adsorption capacity, adsorption kinetics, and selectivity) of novel amidoxime-based polymeric adsorbents developed at Oak Ridge National Laboratory (ORNL) under natural seawater exposure conditions. This report describes the performance of three formulations (38H, AF1, AI8)more » of amidoxime-based polymeric adsorbent produced at ORNL in MSL s ambient seawater testing facility. The adsorbents were produced in two forms, fibrous material (40-100 mg samples) and braided material (5-10 g samples), exposed to natural seawater using flow-through columns and recirculating flumes. All three formulations demonstrated high 56 day uranium adsorption capacity (>3 gU/kg adsorbent). The AF1 formulation had the best uranium adsorption performance, with 56-day capacity of 3.9 g U/kg adsorbent, saturation capacity of 5.4 g U/kg adsorbent, and ~25 days half-saturation time. The two exposure methods, flow-through columns and flumes were demonstrated to produce similar performance results, providing confidence that the test methods were reliable, that scaling up from 10 s of mg quantities of exposure in flow-through columns to gram quantities in flumes produced similar results, and that the manufacturing process produces a homogenous adsorbent. Adsorption kinetics appear to be element specific, with half-saturation times ranging from minutes for the major cations in seawater to 8-10weeks for V and Fe. Reducing the exposure time provides a potential pathway to improve the adsorption capacity of U by reducing the V/U ratio on the adsorbent.« less

Polyoxylglycerides and glycerides: effects of manufacturing parameters on API stability, excipient functionality and processing.

PubMed

Jannin, Vincent; Rodier, Jean-David; Musakhanian, Jasmine

2014-05-15

Lipid-based formulations are a viable option to address modern drug delivery challenges such as increasing the oral bioavailability of poorly water-soluble active pharmaceutical ingredients (APIs), or sustaining the drug release of molecules intended for chronic diseases. Esters of fatty acids and glycerol (glycerides) and polyethylene-glycols (polyoxylglycerides) are two main classes of lipid-based excipients used by oral, dermal, rectal, vaginal or parenteral routes. These lipid-based materials are more and more commonly used in pharmaceutical drug products but there is still a lack of understanding of how the manufacturing processes, processing aids, or additives can impact the chemical stability of APIs within the drug product. In that regard, this review summarizes the key parameters to look at when formulating with lipid-based excipients in order to anticipate a possible impact on drug stability or variation of excipient functionality. The introduction presents the chemistry of natural lipids, fatty acids and their properties in relation to the extraction and refinement processes. Then, the key parameters during the manufacturing process influencing the quality of lipid-based excipients are provided. Finally, their critical characteristics are discussed in relation with their intended functionality and ability to interact with APIs and others excipients within the formulation. Copyright © 2014. Published by Elsevier B.V.

Strengthening community participation in reducing GHG emission from forest and peatland fire

NASA Astrophysics Data System (ADS)

Thoha, A. S.; Saharjo, B. H.; Boer, R.; Ardiansyah, M.

2018-02-01

Strengthening community participation is needed to find solutions to encourage community more participate in reducing Green House Gas (GHG) from forest and peatland fire. This research aimed to identify stakeholders that have the role in forest and peatland fire control and to formulate strengthening model of community participation through community-based early warning fire. Stakeholder mapping and action research were used to determine stakeholders that had potential influence and interest and to formulate strengthening model of community participation in reducing GHG from forest and peatland fire. There was found that position of key players in the mapping of stakeholders came from the government institution. The existence of community-based fire control group can strengthen government institution through collaborating with stakeholders having strong interest and influence. Moreover, it was found several local knowledge in Kapuas District about how communities predict drought that have potential value for developing the community-based early warning fire system. Formulated institutional model in this research also can be further developed as a model institution in the preservation of natural resources based on local knowledge. In conclusion, local knowledge and community-based fire groups can be integrated within strengthening model of community participation in reducing GHG from forest and peatland fire.

Bioavailability of organoclay formulations of atrazine in soil.

PubMed

Trigo, Carmen; Koskinen, William C; Celis, Rafael; Sadowsky, Michael J; Hermosín, María C; Cornejo, Juan

2010-11-24

Pesticide formulations based on organoclays have been proposed to prolong the efficacy and reduce the environmental impact of pesticides in soil. This research addressed the question of whether atrazine in organoclay-based formulations is irreversibly sorbed or is bioavailable for bacterial degradation in soil. Different cations of l-carnitine (CAR), tyramine (TYRAM), hexadimethrine (HEXADIM), phenyltrimethylammonium (PTMA), hexadecyltrimethylammonium (HDTMA), and Fe(III) were incorporated into Na-rich Wyoming montmorillonite (SWy-2) and Ca-rich Arizona montmorillonite (SAz-1) at 100% of the cation exchange capacity (CEC) of the clays as a strategy to enhance the affinity of the clay minerals for atrazine. A Buse loam soil from Becker, MN, was treated with three organoclay-based formulations of 14C-atrazine or free herbicide and incubated for 2 weeks. To determine the bioavailability of 14C-atrazine, the soil was inoculated with Pseudomonas sp. strain ADP, which rapidly mineralizes atrazine. At day 0, and after a 2 week incubation, mineralization and the amount of 14C-atrazine residues distributed between the aqueous-extractable, methanol-extractable, and bound fractions in the soil were determined to characterize the availability of nonaged and aged atrazine residues. By the end of the 2 week incubation, the microorganisms had mineralized >80% of the initial readily available (water-extractable) and >70% of the less readily available (methanol-extractable) 14C-atrazine in the soil. Bound residues increased from <4% at day 0 to ∼17% after the 2 week incubation for both the formulated and free forms of atrazine. The results of these incubation experiments show that the bioavailabilities of atrazine were similar in the case of the organoclay formulations and as free atrazine. This indicated that whereas more atrazine was sorbed and less likely to be transported in soil, when formulated as organoclay complexes, it was ultimately accessible to degrading bacteria, so that the herbicide is likely to be naturally attenuated by soil microorganisms.

Segmentation of heterogeneous blob objects through voting and level set formulation

PubMed Central

Chang, Hang; Yang, Qing; Parvin, Bahram

2009-01-01

Blob-like structures occur often in nature, where they aid in cueing and the pre-attentive process. These structures often overlap, form perceptual boundaries, and are heterogeneous in shape, size, and intensity. In this paper, voting, Voronoi tessellation, and level set methods are combined to delineate blob-like structures. Voting and subsequent Voronoi tessellation provide the initial condition and the boundary constraints for each blob, while curve evolution through level set formulation provides refined segmentation of each blob within the Voronoi region. The paper concludes with the application of the proposed method to a dataset produced from cell based fluorescence assays and stellar data. PMID:19774202

Teleparallel equivalent of Lovelock gravity

NASA Astrophysics Data System (ADS)

González, P. A.; Vásquez, Yerko

2015-12-01

There is a growing interest in modified gravity theories based on torsion, as these theories exhibit interesting cosmological implications. In this work inspired by the teleparallel formulation of general relativity, we present its extension to Lovelock gravity known as the most natural extension of general relativity in higher-dimensional space-times. First, we review the teleparallel equivalent of general relativity and Gauss-Bonnet gravity, and then we construct the teleparallel equivalent of Lovelock gravity. In order to achieve this goal, we use the vielbein and the connection without imposing the Weitzenböck connection. Then, we extract the teleparallel formulation of the theory by setting the curvature to null.

Multi-Stage Convex Relaxation Methods for Machine Learning

DTIC Science & Technology

2013-03-01

Many problems in machine learning can be naturally formulated as non-convex optimization problems. However, such direct nonconvex formulations have...original nonconvex formulation. We will develop theoretical properties of this method and algorithmic consequences. Related convex and nonconvex machine learning methods will also be investigated.

Artificial evolution by viability rather than competition.

PubMed

Maesani, Andrea; Fernando, Pradeep Ruben; Floreano, Dario

2014-01-01

Evolutionary algorithms are widespread heuristic methods inspired by natural evolution to solve difficult problems for which analytical approaches are not suitable. In many domains experimenters are not only interested in discovering optimal solutions, but also in finding the largest number of different solutions satisfying minimal requirements. However, the formulation of an effective performance measure describing these requirements, also known as fitness function, represents a major challenge. The difficulty of combining and weighting multiple problem objectives and constraints of possibly varying nature and scale into a single fitness function often leads to unsatisfactory solutions. Furthermore, selective reproduction of the fittest solutions, which is inspired by competition-based selection in nature, leads to loss of diversity within the evolving population and premature convergence of the algorithm, hindering the discovery of many different solutions. Here we present an alternative abstraction of artificial evolution, which does not require the formulation of a composite fitness function. Inspired from viability theory in dynamical systems, natural evolution and ethology, the proposed method puts emphasis on the elimination of individuals that do not meet a set of changing criteria, which are defined on the problem objectives and constraints. Experimental results show that the proposed method maintains higher diversity in the evolving population and generates more unique solutions when compared to classical competition-based evolutionary algorithms. Our findings suggest that incorporating viability principles into evolutionary algorithms can significantly improve the applicability and effectiveness of evolutionary methods to numerous complex problems of science and engineering, ranging from protein structure prediction to aircraft wing design.

Formulation and stabilization of nano-/microdispersion systems using naturally occurring edible polyelectrolytes by electrostatic deposition and complexation.

PubMed

Kuroiwa, Takashi; Kobayashi, Isao; Chuah, Ai Mey; Nakajima, Mitsutoshi; Ichikawa, Sosaku

2015-12-01

This review paper presents an overview of the formulation and functionalization of nano-/microdispersion systems composed of edible materials. We first summarized general aspects on the stability of colloidal systems and the roles of natural polyelectrolytes such as proteins and ionic polysaccharides for the formation and stabilization of colloidal systems. Then we introduced our research topics on (1) stabilization of emulsions by the electrostatic deposition using natural polyelectrolytes and (2) formulation of stable nanodispersion systems by complexation of natural polyelectrolytes. In both cases, the preparation procedures were relatively simple, without high energy input or harmful chemical addition. The properties of the nano-/microdispersion systems, such as particle size, surface charge and dispersion stability were significantly affected by the concerned materials and preparation conditions, including the type and concentration of used natural polyelectrolytes. These dispersion systems would be useful for developing novel foods having high functionality and good stability. Copyright © 2015 Elsevier B.V. All rights reserved.

Wavelet-based spectral finite element dynamic analysis for an axially moving Timoshenko beam

NASA Astrophysics Data System (ADS)

Mokhtari, Ali; Mirdamadi, Hamid Reza; Ghayour, Mostafa

2017-08-01

In this article, wavelet-based spectral finite element (WSFE) model is formulated for time domain and wave domain dynamic analysis of an axially moving Timoshenko beam subjected to axial pretension. The formulation is similar to conventional FFT-based spectral finite element (SFE) model except that Daubechies wavelet basis functions are used for temporal discretization of the governing partial differential equations into a set of ordinary differential equations. The localized nature of Daubechies wavelet basis functions helps to rule out problems of SFE model due to periodicity assumption, especially during inverse Fourier transformation and back to time domain. The high accuracy of WSFE model is then evaluated by comparing its results with those of conventional finite element and SFE results. The effects of moving beam speed and axial tensile force on vibration and wave characteristics, and static and dynamic stabilities of moving beam are investigated.

Processing effects on physicochemical properties of creams formulated with modified milk fat.

PubMed

Bolling, J C; Duncan, S E; Eigel, W N; Waterman, K M

2005-04-01

Type of thermal process [high temperature, short time pasteurization (HTST) or ultra-high temperature pasteurization (UHT)] and homogenization sequence (before or after pasteurization) were examined for influence on the physicochemical properties of natural cream (20% milk fat) and creams formulated with 20% low-melt, fractionated butteroil emulsified with skim milk, or buttermilk and butter-derived aqueous phase. Homogenization sequence influenced physicochemical makeup of the creams. Creams homogenized before pasteurization contained more milk fat surface material, higher phospholipid levels, and less protein at the milk fat interface than creams homogenized after pasteurization. Phosphodiesterase I activity was higher (relative to protein on lipid globule surface) when cream was homogenized before pasteurization. Creams formulated with skim milk and modified milk fat had relatively more phospholipid adsorbed at the milk fat interface. Ultra-high-temperature-pasteurized natural and reformulated creams were higher in viscosity at all shear rates investigated compared with HTST-pasteurized creams. High-temperature, short time-pasteurized natural cream was more viscous than HTST-pasteurized reformulated creams at most shear rates investigated. High-temperature, short time-pasteurized creams had better emulsion stability than UHT-pasteurized creams. Cream formulated with buttermilk had creaming stability most comparable to natural cream, and cream formulated with skim milk and modified butteroil was least stable to creaming. Most creams feathered in a pH range of 5.00 to 5.20, indicating that they were moderately stable to slightly unstable emulsions. All processing sequences yielded creams within sensory specifications with the exception of treatments homogenized before UHT pasteurization and skim milk formulations homogenized after UHT pasteurization.

A nanocrystal-based formulation improves the pharmacokinetic performance and therapeutic response of albendazole in dogs.

PubMed

Paredes, Alejandro Javier; Litterio, Nicolás; Dib, Alicia; Allemandi, Daniel Alberto; Lanusse, Carlos; Bruni, Sergio Sánchez; Palma, Santiago Daniel

2018-01-01

Here, we aimed to assess the pharmacokinetic performance and therapeutic response (anthelmintic efficacy) of an albendazole (ABZ) nano-sized formulation in dogs. In the pharmacokinetic study, ABZ self-dispersible nanocrystals (SDNCS) and a control formulation were administered orally to healthy dogs (n = 6). The concentrations of the sulphoxide metabolite in plasma were determined by high-performance liquid chromatography. For the anthelmintic efficacy trial, SDNCS and a commercially available formulation of ABZ were given to naturally parasitised dogs. The number of Ancylostoma caninum eggs in the faeces was determined using the McMaster technique. The area under the curve, Tmax and Cmax for the SDNCS were improved compared to the control. The efficacy study showed no statistical differences between the SDNCS and the commercial formulation at the doses of 25 and 12.5 mg/kg. However, significant differences (P < 0.05) between the treatments were found at 6.25 mg/kg (a quarter of the reference dose) with a reduction in the faecal nematode egg counts of 62.0 ± 21.1% and 100 ± 0% for the control and SDNCS, respectively. The improved pharmacokinetic performance observed for the novel formulation of ABZ correlated with an improved in vivo therapeutic response against a model intestinal nematode parasite in dogs. © 2017 Royal Pharmaceutical Society.

Assessment of a liquid larval diet for rearing Dacus and Bactrocera species (Diptera:Tephritidae), in Western Africa

USDA-ARS?s Scientific Manuscript database

The fruit fly larval diet formulations developed by USDA-ARS were used in this study to compare with other artificial and natural diet to rear two Dacus species. The evaluation was based on the parameters of egg hatch, pupal production, adult emergence, flight ability, and productivity. This study s...

Quercetin as natural stabilizing agent for bio-polymer

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

Morici, Elisabetta; Arrigo, Rossella; Dintcheva, Nadka Tzankova

The introduction of antioxidants in polymers is the main way to prevent or delay the degradation process. In particular natural antioxidants receive attention in the food industry also because of their presumed safety. In this work bio-polymers, i.e. a commercial starch-based polymer (Mater-Bi®) and a bio-polyester (PLA), and a bio-polyether (PEO) were additivated with quercetin, a natural flavonoid antioxidants, in order to formulate bio-based films for ecosustainable packaging and outdoor applications. The photo-oxidation behavior of unstabilized and quercetin stabilized films was analyzed and compared with the behavior of films additivated with a commercial synthetic light stabilizer. The quercetin is ablemore » to slow down the photo-degradation rate of all bio-polymeric films investigated in similar way to the synthetic stabilizer.« less

Quercetin as natural stabilizing agent for bio-polymer

NASA Astrophysics Data System (ADS)

Morici, Elisabetta; Arrigo, Rossella; Dintcheva, Nadka Tzankova

2014-05-01

The introduction of antioxidants in polymers is the main way to prevent or delay the degradation process. In particular natural antioxidants receive attention in the food industry also because of their presumed safety. In this work bio-polymers, i.e. a commercial starch-based polymer (Mater-Bi®) and a bio-polyester (PLA), and a bio-polyether (PEO) were additivated with quercetin, a natural flavonoid antioxidants, in order to formulate bio-based films for ecosustainable packaging and outdoor applications. The photo-oxidation behavior of unstabilized and quercetin stabilized films was analyzed and compared with the behavior of films additivated with a commercial synthetic light stabilizer. The quercetin is able to slow down the photo-degradation rate of all bio-polymeric films investigated in similar way to the synthetic stabilizer.

Formulation and optimization by experimental design of eco-friendly emulsions based on d-limonene.

PubMed

Pérez-Mosqueda, Luis M; Trujillo-Cayado, Luis A; Carrillo, Francisco; Ramírez, Pablo; Muñoz, José

2015-04-01

d-Limonene is a natural occurring solvent that can replace more pollutant chemicals in agrochemical formulations. In the present work, a comprehensive study of the influence of dispersed phase mass fraction, ϕ, and of the surfactant/oil ratio, R, on the emulsion stability and droplet size distribution of d-limonene-in-water emulsions stabilized by a non-ionic triblock copolymer surfactant has been carried out. An experimental full factorial design 3(2) was conducted in order to optimize the emulsion formulation. The independent variables, ϕ and R were studied in the range 10-50 wt% and 0.02-0.1, respectively. The emulsions studied were mainly destabilized by both creaming and Ostwald ripening. Therefore, initial droplet size and an overall destabilization parameter, the so-called turbiscan stability index, were used as dependent variables. The optimal formulation, comprising minimum droplet size and maximum stability was achieved at ϕ=50 wt%; R=0.062. Furthermore, the surface response methodology allowed us to obtain the formulation yielding sub-micron emulsions by using a single step rotor/stator homogenizer process instead of most commonly used two-step emulsification methods. In addition, the optimal formulation was further improved against Ostwald ripening by adding silicone oil to the dispersed phase. The combination of these experimental findings allowed us to gain a deeper insight into the stability of these emulsions, which can be applied to the rational development of new formulations with potential application in agrochemical formulations. Copyright © 2015 Elsevier B.V. All rights reserved.

Dropwise additive manufacturing of pharmaceutical products for amorphous and self emulsifying drug delivery systems.

PubMed

Içten, Elçin; Purohit, Hitesh S; Wallace, Chelsey; Giridhar, Arun; Taylor, Lynne S; Nagy, Zoltan K; Reklaitis, Gintaras V

2017-05-30

The improvements in healthcare systems and the advent of the precision medicine initiative have created the need to develop more innovative manufacturing methods for the delivery and production of individualized dosing and personalized treatments. In accordance with the changes observed in healthcare systems towards more innovative therapies, this paper presents dropwise additive manufacturing of pharmaceutical products (DAMPP) for small scale, distributed manufacturing of individualized dosing as an alternative to conventional manufacturing methods A dropwise additive manufacturing process for amorphous and self-emulsifying drug delivery systems is reported, which utilizes drop-on-demand printing technology for automated and controlled deposition of melt-based formulations onto inert tablets. The advantages of drop on demand technology include reproducible production of droplets with adjustable sizing and high placement accuracy, which enable production of individualized dosing even for low dose and high potency drugs. Flexible use of different formulations, such as lipid-based formulations, allows enhancement of the solubility of poorly water soluble and highly lipophilic drugs with DAMPP. Here, DAMPP is used to produce solid oral dosage forms from melts of an active pharmaceutical ingredient and a surfactant. The dosage forms are analyzed to show the amorphous nature, self-emulsifying drug delivery system characteristics and dissolution behavior of these formulations. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessing Mission Impact of Cyberattacks: Report of the NATO IST-128 Workshop

DTIC Science & Technology

2015-12-01

simulation) perspective. This would be natural, considering that the cybersecurity problem is highly adversarial in nature. Because it involves intelligent ...be formulated as a partial information game; artificial intelligence techniques might help here. Yet another style of problem formulation that...computational information processing for weapons, intelligence , communication, and logistics systems continues to increase the vulnerability of

Development of bioactive coatings based on γ-irradiated proteins to preserve strawberries

NASA Astrophysics Data System (ADS)

Vu, K. D.; Hollingsworth, R. G.; Salmieri, S.; Takala, P. N.; Lacroix, M.

2012-08-01

Gamma irradiation was applied for creating cross-linked proteins to enhance the physicochemical properties of edible films made of calcium caseinate, whey protein isolate and glycerol. The characteristics of γ irradiated cross-linked proteins were analyzed by Fourier Transform Infrared spectroscopy. A second derivative spectra exhibited changes in band intensities that were correlated to an increase of β-sheet structure and a decrease of α-helix and unordered fractions of γ irradiated-cross-linked proteins as compared to the control without irradiation. Furthermore, on addition of methylcellulose to the irradiated protein matrix it was found that it has potential in enhancing the puncture strength and has no detrimental effect on water vapor permeability of protein based films. Finally, these film formulations were used as bioactive edible coatings containing natural antimicrobial agents (limonene and peppermint) to preserve the shelf life of fresh strawberries during storage. The bioactive coatings containing peppermint was found to be more efficient as preserving coatings than the formulations containing limonene. Irradiated proteins/methylcellulose/peppermint formulation had only 40% of decay at day 8 while it was 65% for the control.

Hydroxyapatite moldable formulation using natural rubber latex as binder.

PubMed

Sailaja, G S; Ramesh, P; Varma, H K

2007-07-01

A simple but efficient processing method for shaping intricate bioceramic green bodies has been developed by using natural rubber latex as binder. Different shapes of hydroxyapatite Ca10(PO4)6(OH)2 (HAP) were molded from a composite formulation containing wet precipitated HAP, natural rubber latex (NRL), and a stabilizer. On controlled heat treatment followed by sintering, dense shapes of HAP contours were obtained. The thermal degradation profile of HAP-NRL composites shows that NRL degrades slowly without any abrupt exotherm. The results of energy dispersive X-ray analysis together with inductively coupled plasma (ICP) analysis indicate that the inorganic residue of NRL does not contain any heavy element. The sintered density of the samples increased with increased HAP content in the formulation and percentage shrinkage reduced accordingly. On varying the HAP content in the formulation from 35 to 95 wt %, the compositions with 85, 90, 92, and 95 wt % HAP showed better flexural strength in the range 40-54 MPa and a flexural modulus value in the range 36-50 GPa. The fracture morphology, as observed by the scanning electron microscope confirms that with increased HAP content in the formulation the sample microstructure attains higher uniformity. The Vickers microhardness for the samples sintered at two different temperatures (1150 and 1250 degrees C) showed that hardness increases with increase in the sintering temperature with a maximum for the highest HAP loaded formulation. Copyright 2006 Wiley Periodicals, Inc.

Larvicidal activity of neem oil (Azadirachta indica) formulation against mosquitoes

PubMed Central

Dua, Virendra K; Pandey, Akhilesh C; Raghavendra, Kamaraju; Gupta, Ashish; Sharma, Trilochan; Dash, Aditya P

2009-01-01

Background Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. Azadirachta indica (Meliaceae) and its derived products have shown a variety of insecticidal properties. The present paper discusses the larvicidal activity of neem-based biopesticide for the control of mosquitoes. Methods Larvicidal efficacy of an emulsified concentrate of neem oil formulation (neem oil with polyoxyethylene ether, sorbitan dioleate and epichlorohydrin) developed by BMR & Company, Pune, India, was evaluated against late 3rd and early 4th instar larvae of different genera of mosquitoes. The larvae were exposed to different concentrations (0.5–5.0 ppm) of the formulation along with untreated control. Larvicidal activity of the formulation was also evaluated in field against Anopheles, Culex, and Aedes mosquitoes. The formulation was diluted with equal volumes of water and applied @ 140 mg a.i./m2 to different mosquito breeding sites with the help of pre calibrated knapsack sprayer. Larval density was determined at pre and post application of the formulation using a standard dipper. Results Median lethal concentration (LC50) of the formulation against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti was found to be 1.6, 1.8 and 1.7 ppm respectively. LC50 values of the formulation stored at 26°C, 40°C and 45°C for 48 hours against Ae. aegypti were 1.7, 1.7, 1.8 ppm while LC90 values were 3.7, 3.7 and 3.8 ppm respectively. Further no significant difference in LC50 and LC90 values of the formulation was observed against Ae. aegypti during 18 months storage period at room temperature. An application of the formulation at the rate of 140 mg a.i./m2 in different breeding sites under natural field conditions provided 98.1% reduction of Anopheles larvae on day 1; thereafter 100% reduction was recorded up to week 1 and more than 80% reduction up to week 3, while percent reduction against Culex larvae was 95.5% on day 1, and thereafter 80% reduction was achieved up to week 3. The formulation also showed 95.1% and, 99.7% reduction of Aedes larvae on day 1 and day 2 respectively; thereafter 100% larval control was observed up to day 7. Conclusion The neem oil formulation was found effective in controlling mosquito larvae in different breeding sites under natural field conditions. As neem trees are widely distributed in India, their formulations may prove to be an effective and eco-friendly larvicide, which could be used as an alternative for malaria control. PMID:19500429

Larvicidal activity of neem oil (Azadirachta indica) formulation against mosquitoes.

PubMed

Dua, Virendra K; Pandey, Akhilesh C; Raghavendra, Kamaraju; Gupta, Ashish; Sharma, Trilochan; Dash, Aditya P

2009-06-08

Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. Azadirachta indica (Meliaceae) and its derived products have shown a variety of insecticidal properties. The present paper discusses the larvicidal activity of neem-based biopesticide for the control of mosquitoes. Larvicidal efficacy of an emulsified concentrate of neem oil formulation (neem oil with polyoxyethylene ether, sorbitan dioleate and epichlorohydrin) developed by BMR & Company, Pune, India, was evaluated against late 3rd and early 4th instar larvae of different genera of mosquitoes. The larvae were exposed to different concentrations (0.5-5.0 ppm) of the formulation along with untreated control. Larvicidal activity of the formulation was also evaluated in field against Anopheles, Culex, and Aedes mosquitoes. The formulation was diluted with equal volumes of water and applied @ 140 mg a.i./m(2) to different mosquito breeding sites with the help of pre calibrated knapsack sprayer. Larval density was determined at pre and post application of the formulation using a standard dipper. Median lethal concentration (LC(50)) of the formulation against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti was found to be 1.6, 1.8 and 1.7 ppm respectively. LC(50) values of the formulation stored at 26 degrees C, 40 degrees C and 45 degrees C for 48 hours against Ae. aegypti were 1.7, 1.7, 1.8 ppm while LC(90) values were 3.7, 3.7 and 3.8 ppm respectively. Further no significant difference in LC(50) and LC(90) values of the formulation was observed against Ae. aegypti during 18 months storage period at room temperature. An application of the formulation at the rate of 140 mg a.i./m(2) in different breeding sites under natural field conditions provided 98.1% reduction of Anopheles larvae on day 1; thereafter 100% reduction was recorded up to week 1 and more than 80% reduction up to week 3, while percent reduction against Culex larvae was 95.5% on day 1, and thereafter 80% reduction was achieved up to week 3. The formulation also showed 95.1% and, 99.7% reduction of Aedes larvae on day 1 and day 2 respectively; thereafter 100% larval control was observed up to day 7. The neem oil formulation was found effective in controlling mosquito larvae in different breeding sites under natural field conditions. As neem trees are widely distributed in India, their formulations may prove to be an effective and eco-friendly larvicide, which could be used as an alternative for malaria control.

A Novel Four-Node Quadrilateral Smoothing Element for Stress Enhancement and Error Estimation

NASA Technical Reports Server (NTRS)

Tessler, A.; Riggs, H. R.; Dambach, M.

1998-01-01

A four-node, quadrilateral smoothing element is developed based upon a penalized-discrete-least-squares variational formulation. The smoothing methodology recovers C1-continuous stresses, thus enabling effective a posteriori error estimation and automatic adaptive mesh refinement. The element formulation is originated with a five-node macro-element configuration consisting of four triangular anisoparametric smoothing elements in a cross-diagonal pattern. This element pattern enables a convenient closed-form solution for the degrees of freedom of the interior node, resulting from enforcing explicitly a set of natural edge-wise penalty constraints. The degree-of-freedom reduction scheme leads to a very efficient formulation of a four-node quadrilateral smoothing element without any compromise in robustness and accuracy of the smoothing analysis. The application examples include stress recovery and error estimation in adaptive mesh refinement solutions for an elasticity problem and an aerospace structural component.

Spray drying formulation of amorphous solid dispersions.

PubMed

Singh, Abhishek; Van den Mooter, Guy

2016-05-01

Spray drying is a well-established manufacturing technique which can be used to formulate amorphous solid dispersions (ASDs) which is an effective strategy to deliver poorly water soluble drugs (PWSDs). However, the inherently complex nature of the spray drying process coupled with specific characteristics of ASDs makes it an interesting area to explore. Numerous diverse factors interact in an inter-dependent manner to determine the final product properties. This review discusses the basic background of ASDs, various formulation and process variables influencing the critical quality attributes (CQAs) of the ASDs and aspects of downstream processing. Also various aspects of spray drying such as instrumentation, thermodynamics, drying kinetics, particle formation process and scale-up challenges are included. Recent advances in the spray-based drying techniques are mentioned along with some future avenues where major research thrust is needed. Copyright © 2015 Elsevier B.V. All rights reserved.

Field theoretical prediction of a property of the tropical cyclone

NASA Astrophysics Data System (ADS)

Spineanu, F.; Vlad, M.

2014-01-01

The large scale atmospheric vortices (tropical cyclones, tornadoes) are complex physical systems combining thermodynamics and fluid-mechanical processes. The late phase of the evolution towards stationarity consists of the vorticity concentration, a well known tendency to self-organization , an universal property of the two-dimensional fluids. It may then be expected that the stationary state of the tropical cyclone has the same nature as the vortices of many other systems in nature: ideal (Euler) fluids, superconductors, Bose-Einsetin condensate, cosmic strings, etc. Indeed it was found that there is a description of the atmospheric vortex in terms of a classical field theory. It is compatible with the more conventional treatment based on conservation laws, but the field theoretical model reveals properties that are almost inaccessible to the conventional formulation: it identifies the stationary states as being close to self-duality. This is of highest importance: the self-duality is known to be the origin of all coherent structures known in natural systems. Therefore the field theoretical (FT) formulation finds that the cuasi-coherent form of the atmospheric vortex (tropical cyclone) at stationarity is an expression of this particular property. In the present work we examine a strong property of the tropical cyclone, which arises in the FT formulation in a natural way: the equality of the masses of the particles associated to the matter field and respectively to the gauge field in the FT model is translated into the equality between the maximum radial extension of the tropical cyclone and the Rossby radius. For the cases where the FT model is a good approximation we calculate characteristic quantities of the tropical cyclone and find good comparison with observational data.

Coarse and nano emulsions for effective delivery of the natural pest control agent pulegone for stored grain protection.

PubMed

Golden, Gilad; Quinn, Elazar; Shaaya, Eli; Kostyukovsky, Moshe; Poverenov, Elena

2018-04-01

One of the most significant contributors to the global food crisis is grain loss during storage, mainly caused by pest insects. Currently, there are two main methods used for insect pest control: fumigation and grain protection using contact insecticides. As some chemical insecticides can harm humans and the environment, there is a global tendency to reduce their use by finding alternative eco-friendly approaches. In this study, the natural pest-managing agent pulegone was encapsulated into coarse and nano emulsions. The emulsions were characterized using spectroscopic and microscopic methods and their stability and pulegone release ability were examined. The insecticidal activity of the prepared formulations against two stored product insects, rice weevil (Sitophilus oryzae L.) and red flour beetle (Tribolium castaneum Herbst), was demonstrated. The nano emulsion-based formulation offered significant advantages and provided powerful bioactivity, with high (> 90%) mortality rates for as long as 5 weeks for both insects, whereas coarse emulsions showed high efficacy for only 1 week. The developed pulegone-based nano emulsions could serve as a model for an effective alternative method for pest control. Although pulegone is from a natural source, toxicological studies should be performed before the widespread application of pulegone or pulegone-containing essential oils to dry food products. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Approximating natural connectivity of scale-free networks based on largest eigenvalue

NASA Astrophysics Data System (ADS)

Tan, S.-Y.; Wu, J.; Li, M.-J.; Lu, X.

2016-06-01

It has been recently proposed that natural connectivity can be used to efficiently characterize the robustness of complex networks. The natural connectivity has an intuitive physical meaning and a simple mathematical formulation, which corresponds to an average eigenvalue calculated from the graph spectrum. However, as a network model close to the real-world system that widely exists, the scale-free network is found difficult to obtain its spectrum analytically. In this article, we investigate the approximation of natural connectivity based on the largest eigenvalue in both random and correlated scale-free networks. It is demonstrated that the natural connectivity of scale-free networks can be dominated by the largest eigenvalue, which can be expressed asymptotically and analytically to approximate natural connectivity with small errors. Then we show that the natural connectivity of random scale-free networks increases linearly with the average degree given the scaling exponent and decreases monotonically with the scaling exponent given the average degree. Moreover, it is found that, given the degree distribution, the more assortative a scale-free network is, the more robust it is. Experiments in real networks validate our methods and results.

Time-variant random interval natural frequency analysis of structures

NASA Astrophysics Data System (ADS)

Wu, Binhua; Wu, Di; Gao, Wei; Song, Chongmin

2018-02-01

This paper presents a new robust method namely, unified interval Chebyshev-based random perturbation method, to tackle hybrid random interval structural natural frequency problem. In the proposed approach, random perturbation method is implemented to furnish the statistical features (i.e., mean and standard deviation) and Chebyshev surrogate model strategy is incorporated to formulate the statistical information of natural frequency with regards to the interval inputs. The comprehensive analysis framework combines the superiority of both methods in a way that computational cost is dramatically reduced. This presented method is thus capable of investigating the day-to-day based time-variant natural frequency of structures accurately and efficiently under concrete intrinsic creep effect with probabilistic and interval uncertain variables. The extreme bounds of the mean and standard deviation of natural frequency are captured through the embedded optimization strategy within the analysis procedure. Three particularly motivated numerical examples with progressive relationship in perspective of both structure type and uncertainty variables are demonstrated to justify the computational applicability, accuracy and efficiency of the proposed method.

The role of water repellents and chemicals in controlling mildew on wood exposed outdoors

Treesearch

W. C. Feist

1984-01-01

The natural look of wood siding, and the retention of that look, has become increasingly popular over the past several years. Many new commercial formulations are being offered for use as clear natural wood finishes. A successful finish will retain color, control mold and mildew, and minimize weathering. Some of these formulations contain a chemical as a mildewcide (...

Development of "all natural" layer-by-layer redispersible solid lipid nanoparticles by nano spray drying technology.

PubMed

Wang, Taoran; Hu, Qiaobin; Zhou, Mingyong; Xia, Yan; Nieh, Mu-Ping; Luo, Yangchao

2016-10-01

Solid lipid nanoparticles (SLNs) have gained tremendous attraction as carriers for controlled drug delivery. Despite numerous advances in the field, one long-standing historical challenge for their practical applications remains unmet: redispersibility after drying. In this work, a novel design of SLNs using a layer-by-layer (LbL) technique was developed and the formulations were optimized by surface response methodology (Box-Behnken design). To the best of our knowledge, this is the first study reporting the fabrication of SLNs from all natural ingredients in the absence of any synthetic surfactants or coatings. The SLNs were prepared by a combined solvent-diffusion and hot homogenization method, with soy lecithin as natural emulsifier (first layer), followed by the subsequent coating with sodium caseinate (second layer) and pectin (third layer), both of which are natural food biopolymers. The adsorption of pectin coating onto caseinate was reinforced by hydrophobic and electrostatic interactions induced by a pH-driven process along with thermal treatment. The innovative nano spray drying technology was further explored to obtain ultra-fine powders of SLNs. Compared to uncoated or single-layer coated SLNs powders, which showed severe aggregation after spray drying, the well-separated particles with spherical shape and smooth surface were obtained for layer-by-layer (LbL) SLNs, which were redispersible into water without variation of dimension, shape and morphology. The SLNs were characterized by Fourier transform infrared and high-performance differential scanning calorimetry for their physical properties. The LbL-coated SLNs based on all natural ingredients have promising features for future applications as drug delivery systems, overcoming the major obstacles in conventional spray drying and redispersing SLNs-based formulations. Copyright © 2016 Elsevier B.V. All rights reserved.

Formulation and in vitro release evaluation of newly synthesized palm kernel oil esters-based nanoemulsion delivery system for 30% ethanolic dried extract derived from local Phyllanthus urinaria for skin antiaging

PubMed Central

Mahdi, Elrashid Saleh; Noor, Azmin Mohd; Sakeena, Mohamed Hameem; Abdullah, Ghassan Z; Abdulkarim, Muthanna F; Sattar, Munavvar Abdul

2011-01-01

Background Recently there has been a remarkable surge of interest about natural products and their applications in the cosmetic industry. Topical delivery of antioxidants from natural sources is one of the approaches used to reverse signs of skin aging. The aim of this research was to develop a nanoemulsion cream for topical delivery of 30% ethanolic extract derived from local Phyllanthus urinaria (P. urinaria) for skin antiaging. Methods Palm kernel oil esters (PKOEs)-based nanoemulsions were loaded with P. urinaria extract using a spontaneous method and characterized with respect to particle size, zeta potential, and rheological properties. The release profile of the extract was evaluated using in vitro Franz diffusion cells from an artificial membrane and the antioxidant activity of the extract released was evaluated using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method. Results Formulation F12 consisted of wt/wt, 0.05% P. urinaria extract, 1% cetyl alcohol, 0.5% glyceryl monostearate, 12% PKOEs, and 27% Tween® 80/Span® 80 (9/1) with a hydrophilic lipophilic balance of 13.9, and a 59.5% phosphate buffer system at pH 7.4. Formulation F36 was comprised of 0.05% P. urinaria extract, 1% cetyl alcohol, 1% glyceryl monostearate, 14% PKOEs, 28% Tween® 80/Span® 80 (9/1) with a hydrophilic lipophilic balance of 13.9, and 56% phosphate buffer system at pH 7.4 with shear thinning and thixotropy. The droplet size of F12 and F36 was 30.74 nm and 35.71 nm, respectively, and their nanosizes were confirmed by transmission electron microscopy images. Thereafter, 51.30% and 51.02% of the loaded extract was released from F12 and F36 through an artificial cellulose membrane, scavenging 29.89% and 30.05% of DPPH radical activity, respectively. Conclusion The P. urinaria extract was successfully incorporated into a PKOEs-based nanoemulsion delivery system. In vitro release of the extract from the formulations showed DPPH radical scavenging activity. These formulations can neutralize reactive oxygen species and counteract oxidative injury induced by ultraviolet radiation and thereby ameliorate skin aging. PMID:22072884

Before Photocopying This Article or Videotaping That Television Show, Make Sure You Understand the "Fair Use" Provision of the Copyright Law.

ERIC Educational Resources Information Center

McCarthy, Martha

1984-01-01

School boards can formulate policies concerning the reproduction and use of copyrighted materials based on recent court interpretations of the following general factors in "fair use" exemption: reasons for copying, nature of reproduced material, amount of work as a whole copied, and effect of copying on potential market for copyrighted…

Mathematical modeling of the aerodynamic characteristics in flight dynamics

NASA Technical Reports Server (NTRS)

Tobak, M.; Chapman, G. T.; Schiff, L. B.

1984-01-01

Basic concepts involved in the mathematical modeling of the aerodynamic response of an aircraft to arbitrary maneuvers are reviewed. The original formulation of an aerodynamic response in terms of nonlinear functionals is shown to be compatible with a derivation based on the use of nonlinear functional expansions. Extensions of the analysis through its natural connection with ideas from bifurcation theory are indicated.

The effect of carbon black filler to the mechanical properties of natural rubber as base isolation system

NASA Astrophysics Data System (ADS)

Ismail, R.; Mahadi, Z. A.; Ishak, I. S.

2018-04-01

This paper presented the study on the effect of carbon black as filler to the mechanical properties of natural rubber for base isolation system. This study used the five formulations with the different amount of carbon black filler for every sample. The samples were tested for tensile, hardness and resilience test. The samples were cured or vulcanized at 1500C for 23 minutes for every formulation. The filler used in this study was the carbon black filler with type N660. The tensile test was done to determine the ability of the sample in term of the elongation with the load at break. The hardness test, it has been done to determine the ability of the sample to resist the load. This hardness was measured in the unit of IRHD. The resilience test was being done to determine the properties of the sample in term of rebound characteristics. The finding of this study showed that, the high the loading of carbon black filler, the high the tensile strength of the sample and the high the hardness of the sample. In term of resilience, it was inversely proportional to the loading of the carbon black filler.

A simple orbit-attitude coupled modelling method for large solar power satellites

NASA Astrophysics Data System (ADS)

Li, Qingjun; Wang, Bo; Deng, Zichen; Ouyang, Huajiang; Wei, Yi

2018-04-01

A simple modelling method is proposed to study the orbit-attitude coupled dynamics of large solar power satellites based on natural coordinate formulation. The generalized coordinates are composed of Cartesian coordinates of two points and Cartesian components of two unitary vectors instead of Euler angles and angular velocities, which is the reason for its simplicity. Firstly, in order to develop natural coordinate formulation to take gravitational force and gravity gradient torque of a rigid body into account, Taylor series expansion is adopted to approximate the gravitational potential energy. The equations of motion are constructed through constrained Hamilton's equations. Then, an energy- and constraint-conserving algorithm is presented to solve the differential-algebraic equations. Finally, the proposed method is applied to simulate the orbit-attitude coupled dynamics and control of a large solar power satellite considering gravity gradient torque and solar radiation pressure. This method is also applicable to dynamic modelling of other rigid multibody aerospace systems.

Biosurfactants in cosmetic formulations: trends and challenges.

PubMed

Vecino, X; Cruz, J M; Moldes, A B; Rodrigues, L R

2017-11-01

Cosmetic products play an essential role in everyone's life. People everyday use a large variety of cosmetic products such as soap, shampoo, toothpaste, deodorant, skin care, perfume, make-up, among others. The cosmetic industry encompasses several environmental, social and economic impacts that are being addressed through the search for more efficient manufacturing techniques, the reduction of waste and emissions and the promotion of personal hygiene, contributing to an improvement of public health and at the same time providing employment opportunities. The current trend among consumers is the pursuit for natural ingredients in cosmetic products, as many of these products exhibit equal, better or additional benefits in comparison with the chemical-based products. In this sense, biosurfactants are natural compounds with great potential in the formulation of cosmetic products given by their biodegradability and impact in health. Indeed, many of these biosurfactants could exhibit a "prebiotic" character. This review covers the current state-of-the-art of biosurfactant research for cosmetic purposes and further discusses the future challenges for cosmetic applications.

Application of Coffee Silverskin in cosmetic formulations: physical/antioxidant stability studies and cytotoxicity effects.

PubMed

Rodrigues, Francisca; Gaspar, Carlos; Palmeira-de-Oliveira, Ana; Sarmento, Bruno; Helena Amaral, M; P P Oliveira, M Beatriz

2016-01-01

Currently, there is an increasing interest of cosmetic industry on natural extracts. The inclusion of antioxidants in topical formulations can contribute to minimize oxidative stress in the skin, which has been associated with aging. Also, questions of sustainability are leading to the study of new cosmetic ingredients obtained from food by-products. Coffee Silverskin (CS) is a food by-product with established antioxidant activity that has not yet been incorporated into a topical formulation. The aim of this study was to evaluate the physical and microbiological stabilities and antioxidant activity of a hand cream formulation containing 2.5% (w/w) of CS extract upon production and after 6 months of shelf-life and in vitro safety/cytotoxicity on skin cell lines after production. The in vitro cytotoxicity was evaluated with MTS and LDH assays, at different concentrations, in HaCaT and HFF-1 cells. Formulations were stored at 25 °C/65% RH and 40 °C/75% RH. Physical, microbiological, and antioxidant stabilities were evaluated by centrifugation, viscosity, total colony count, DPPH and total phenolic content (TPC). The hand cream containing 2.5% (w/w) of CS extract showed stable physical characteristics independently of the storage conditions. The DPPH activity and TPC of the CS formulation were significantly higher compared with those of the base formulation. However, during storage, the antioxidant activity decreases slightly. Microbiological quality was also confirmed. No cytotoxic effects were observed. It is possible to suggest that this formulation is stable under extreme conditions and safe for topical use.

A Novel Self-Microemulsifying System for the Simultaneous Delivery and Enhanced Oral Absorption of Curcumin and Resveratrol.

PubMed

Jaisamut, Patcharawalai; Wiwattanawongsa, Kamonthip; Wiwattanapatapee, Ruedeekorn

2017-03-01

The use of curcumin and resveratrol in combination has now become increasingly of interest because of their synergistic effects as therapeutic agents for various diseases, especially cancer. To overcome the poor oral bioavailability of both compounds and improve patient compliance, a novel self-microemulsifying formulation containing curcumin together with resveratrol was developed. Capryol 90, Cremophor EL, and Labrasol were selected as the oil, surfactant, and co-surfactant in the formulation, respectively, based on the solubility study of both compounds. More than 70 % and 80 % of curcumin and resveratrol, respectively, were released in 20 min. The formulation formed a fine oil in water microemulsion with droplet sizes in aqueous media of 15-20 nm. In addition, the formulation containing curcumin and resveratrol showed greater antioxidant activity than that of the formulations with individual compounds, while the cytotoxic activity against HT-29 of the co-formulation (IC 50  = 18.25 µM; curcumin and resveratrol in the ratio 1 : 1) was less than the formulation with only curcumin (IC 50  = 30.1 µM) and only resveratrol (IC 50  = 25.4 µM). After oral administration to rabbits, the self-microemulsifying formulation containing curcumin together with resveratrol increased the total plasma concentrations of curcumin and resveratrol by 10-fold and 6-fold, respectively, compared to the unformulated combination. This study clearly demonstrated the potential use of the self-microemulsifying formulation for co-delivery, and enhanced oral absorption of poorly water-soluble natural compounds. In addition, the combination was found to produce synergistic antioxidant activity and cytotoxicity against HT-29 cells. Georg Thieme Verlag KG Stuttgart · New York.

Phenotypic Screening Identifies Synergistically Acting Natural Product Enhancing the Performance of Biomaterial Based Wound Healing.

PubMed

Sivasubramanian, Srinivasan; Chandrasekar, Gayathri; Svensson Akusjärvi, Sara; Thangam, Ramar; Sathuvan, Malairaj; Kumar, R B S; Hussein, Hawraa; Vincent, Savariar; Madhan, Balaraman; Gunasekaran, Palani; Kitambi, Satish S

2017-01-01

The potential of multifunctional wound heal biomaterial relies on the optimal content of therapeutic constituents as well as the desirable physical, chemical, and biological properties to accelerate the healing process. Formulating biomaterials such as amnion or collagen based scaffolds with natural products offer an affordable strategy to develop dressing material with high efficiency in healing wounds. Using image based phenotyping and quantification, we screened natural product derived bioactive compounds for modulators of types I and III collagen production from human foreskin derived fibroblast cells. The identified hit was then formulated with amnion to develop a biomaterial, and its biophysical properties, in vitro and in vivo effects were characterized. In addition, we performed functional profiling analyses by PCR array to understand the effect of individual components of these materials on various genes such as inflammatory mediators including chemokines and cytokines, growth factors, fibroblast stimulating markers for collagen secretion, matrix metalloproteinases, etc., associated with wound healing. FACS based cell cycle analyses were carried out to evaluate the potential of biomaterials for induction of proliferation of fibroblasts. Western blot analyses was done to examine the effect of biomaterial on collagen synthesis by cells and compared to cells grown in the presence of growth factors. This work demonstrated an uncomplicated way of identifying components that synergistically promote healing. Besides, we demonstrated that modulating local wound environment using biomaterials with bioactive compounds could enhance healing. This study finds that the developed biomaterials offer immense scope for healing wounds by means of their skin regenerative features such as anti-inflammatory, fibroblast stimulation for collagen secretion as well as inhibition of enzymes and markers impeding the healing, hydrodynamic properties complemented with other features including non-toxicity, biocompatibility, and safety.

Phenotypic Screening Identifies Synergistically Acting Natural Product Enhancing the Performance of Biomaterial Based Wound Healing

PubMed Central

Sivasubramanian, Srinivasan; Chandrasekar, Gayathri; Svensson Akusjärvi, Sara; Thangam, Ramar; Sathuvan, Malairaj; Kumar, R. B. S.; Hussein, Hawraa; Vincent, Savariar; Madhan, Balaraman; Gunasekaran, Palani; Kitambi, Satish S.

2017-01-01

The potential of multifunctional wound heal biomaterial relies on the optimal content of therapeutic constituents as well as the desirable physical, chemical, and biological properties to accelerate the healing process. Formulating biomaterials such as amnion or collagen based scaffolds with natural products offer an affordable strategy to develop dressing material with high efficiency in healing wounds. Using image based phenotyping and quantification, we screened natural product derived bioactive compounds for modulators of types I and III collagen production from human foreskin derived fibroblast cells. The identified hit was then formulated with amnion to develop a biomaterial, and its biophysical properties, in vitro and in vivo effects were characterized. In addition, we performed functional profiling analyses by PCR array to understand the effect of individual components of these materials on various genes such as inflammatory mediators including chemokines and cytokines, growth factors, fibroblast stimulating markers for collagen secretion, matrix metalloproteinases, etc., associated with wound healing. FACS based cell cycle analyses were carried out to evaluate the potential of biomaterials for induction of proliferation of fibroblasts. Western blot analyses was done to examine the effect of biomaterial on collagen synthesis by cells and compared to cells grown in the presence of growth factors. This work demonstrated an uncomplicated way of identifying components that synergistically promote healing. Besides, we demonstrated that modulating local wound environment using biomaterials with bioactive compounds could enhance healing. This study finds that the developed biomaterials offer immense scope for healing wounds by means of their skin regenerative features such as anti-inflammatory, fibroblast stimulation for collagen secretion as well as inhibition of enzymes and markers impeding the healing, hydrodynamic properties complemented with other features including non-toxicity, biocompatibility, and safety. PMID:28769790

A robust multi-kernel change detection framework for detecting leaf beetle defoliation using Landsat 7 ETM+ data

NASA Astrophysics Data System (ADS)

Anees, Asim; Aryal, Jagannath; O'Reilly, Małgorzata M.; Gale, Timothy J.; Wardlaw, Tim

2016-12-01

A robust non-parametric framework, based on multiple Radial Basic Function (RBF) kernels, is proposed in this study, for detecting land/forest cover changes using Landsat 7 ETM+ images. One of the widely used frameworks is to find change vectors (difference image) and use a supervised classifier to differentiate between change and no-change. The Bayesian Classifiers e.g. Maximum Likelihood Classifier (MLC), Naive Bayes (NB), are widely used probabilistic classifiers which assume parametric models, e.g. Gaussian function, for the class conditional distributions. However, their performance can be limited if the data set deviates from the assumed model. The proposed framework exploits the useful properties of Least Squares Probabilistic Classifier (LSPC) formulation i.e. non-parametric and probabilistic nature, to model class posterior probabilities of the difference image using a linear combination of a large number of Gaussian kernels. To this end, a simple technique, based on 10-fold cross-validation is also proposed for tuning model parameters automatically instead of selecting a (possibly) suboptimal combination from pre-specified lists of values. The proposed framework has been tested and compared with Support Vector Machine (SVM) and NB for detection of defoliation, caused by leaf beetles (Paropsisterna spp.) in Eucalyptus nitens and Eucalyptus globulus plantations of two test areas, in Tasmania, Australia, using raw bands and band combination indices of Landsat 7 ETM+. It was observed that due to multi-kernel non-parametric formulation and probabilistic nature, the LSPC outperforms parametric NB with Gaussian assumption in change detection framework, with Overall Accuracy (OA) ranging from 93.6% (κ = 0.87) to 97.4% (κ = 0.94) against 85.3% (κ = 0.69) to 93.4% (κ = 0.85), and is more robust to changing data distributions. Its performance was comparable to SVM, with added advantages of being probabilistic and capable of handling multi-class problems naturally with its original formulation.

The effect of formulative parameters on the size and physical stability of SLN based on "green" components.

PubMed

Soddu, Elena; Rassu, Giovanna; Cossu, Massimo; Giunchedi, Paolo; Cerri, Guido; Gavini, Elisabetta

2016-01-01

Cocoa butter (CB) is a largely used excipient in pharmaceutical field. Aim of this work was to set formulative parameters for the preparation of SLN based on "green" lipid matrix for drug delivery as natural, both human and environmental safe systems. Double emulsion technique (w1/o/w2) was selected for SLN preparation. The effect on the dimensional properties of different surfactants (Tween 80 and PEG 40 monostearate) and co-surfactants (PEG400 monostearate, Emulium® Kappa2 and Plurol®Stearique) at different concentrations was evaluated. Stability tests were performed. SLN dispersions were exsiccated and the effect of the dried process on SLN size was evaluated. The influence of temperature on SLN dimensions was investigated at 37 °C. MTT test was performed on raw materials and formulations. The w1/o/w2 is suitable, rapid and economic technique for the preparation of CB SLN. Tween 80-Plurol Stearique combination gives the best results: particles size less than 400 nm and PI of about 0.4 are obtained when PS 2% is used. Both raw materials and formulations are safe. The importance to evaluate the effect of different surfactant and/or co-surfactant on the dimensional properties of SLN is evident by selecting substances with preferable safety profiles, and favorable environmental properties to develop stable "green" SLN.

Analysis and antibacterial activity of Nigella sativa essential oil formulated in microemulsion system.

PubMed

Shaaban, Hamdy A; Sadek, Zainab; Edris, Amr E; Saad-Hussein, Amal

2015-01-01

The Essential oil (EO) of Nigella sativa (black cumin) was extracted from the crude oil and the volatile constituents were characterized using gas chromatographic analysis. The EO was formulated in water-based microemulsion system and its antibacterial activity against six pathogenic bacteria was evaluated using the agar well diffusion method. This activity was compared with two other well known biologically active natural and synthetic antimicrobials namely eugenol and Ceftriaxone(®). Results showed that N. sativa EO microemulsion was highly effective against S. aureus, B. cereus and S. typhimurium even at the lowest tested concentration of that EO in the microemulsion (100.0 μg/well). Interestingly, the EO microemulsion showed higher antibacterial activity than Ceftriaxone solution against S. typhimurium at 400.0 μg/well and almost comparable activity against E. coli at 500.0 μg/well. No activity was detected for the EO microemulsion against L. monocytogenes and P. aeruginosa. Eugenol which was also formulated in microemulsion was less effective than N. sativa EO microemulsion except against P. aeruginosa. The synthetic antibiotic (Ceftriaxone) was effective against most of the six tested bacterial strains. This work is the first report revealing the formulation of N. sativa EO in microemulsion system and investigating its antibacterial activity. The results may offer potential application of that water-based microemulsion in controlling the prevalence of some pathogenic bacteria.

Analytical Expressions for Thermo-Osmotic Permeability of Clays

NASA Astrophysics Data System (ADS)

Gonçalvès, J.; Ji Yu, C.; Matray, J.-M.; Tremosa, J.

2018-01-01

In this study, a new formulation for the thermo-osmotic permeability of natural pore solutions containing monovalent and divalent cations is proposed. The mathematical formulation proposed here is based on the theoretical framework supporting thermo-osmosis which relies on water structure alteration in the pore space of surface-charged materials caused by solid-fluid electrochemical interactions. The ionic content balancing the surface charge of clay minerals causes a disruption in the hydrogen bond network when more structured water is present at the clay surface. Analytical expressions based on our heuristic model are proposed and compared to the available data for NaCl solutions. It is shown that the introduction of divalent cations reduces the thermo-osmotic permeability by one third compared to the monovalent case. The analytical expressions provided here can be used to advantage for safety calculations in deep underground nuclear waste repositories.

Stability analysis of internally damped rotating composite shafts using a finite element formulation

NASA Astrophysics Data System (ADS)

Ben Arab, Safa; Rodrigues, José Dias; Bouaziz, Slim; Haddar, Mohamed

2018-04-01

This paper deals with the stability analysis of internally damped rotating composite shafts. An Euler-Bernoulli shaft finite element formulation based on Equivalent Single Layer Theory (ESLT), including the hysteretic internal damping of composite material and transverse shear effects, is introduced and then used to evaluate the influence of various parameters: stacking sequences, fiber orientations and bearing properties on natural frequencies, critical speeds, and instability thresholds. The obtained results are compared with those available in the literature using different theories. The agreement in the obtained results show that the developed Euler-Bernoulli finite element based on ESLT including hysteretic internal damping and shear transverse effects can be effectively used for the stability analysis of internally damped rotating composite shafts. Furthermore, the results revealed that rotor stability is sensitive to the laminate parameters and to the properties of the bearings.

Mechanism of cross-sectoral coordination between nature protection and forestry in the Natura 2000 formulation process in Slovakia.

PubMed

Sarvašová, Zuzana; Sálka, Jaroslav; Dobšinská, Zuzana

2013-09-01

Nature protection as a policy sector is not isolated and is directly or indirectly influenced by many other sectors (e.g. forestry, water management, rural development, energy, etc.). These policy sectors are neither completely segmented nor unaffected by the decisions taken in other policy sectors. Policy formulation in nature protection is therefore also influenced by different sectors. For that reason it is inevitable to stress the need for inter-sectoral coordination to assure their policy coherence. The aim of this article is to describe the mechanism and modes of cross-sectoral coordination and to analyze the relevant actors and their interaction, using the case of the Natura 2000 formulation process in Slovakia. The European Union (EU) set up an ecological network of special protected areas, known as Natura 2000 to ensure biodiversity by conserving natural habitats and wild fauna and flora in the territory of the Member States. An optimized nature protection must therefore carefully consider existing limits and crossdisciplinary relationships at the EU, national and regional levels. The relations between forestry and biodiversity protection are analyzed using the advocacy coalition framework (ACF). The ACF is used for analyzing how two coalitions, in this case ecological and forest owners' coalitions, advocate or pursue their beliefs from the nature protection and forestry policy field. The whole process is illustrated at the regional scale on the case study of Natura 2000 sites formulation in the Slovak Republic. For better reliability and validity of research, a combination of various empiric research methods was used, supported by existing theories. So called triangulation of sociological research or triangulation of methods consists of mutual results testing of individual methodological steps through identifying corresponding political-science theories, assessing their formal points using primary and secondary document analysis and assessing their informal points with standardized interviews with experts. We can conclude that adequate cross-sectoral coordination represented by new modes is missing and the formulation of the Natura 2000 network in Slovakia shows deficits resulting from different policy beliefs concerning nature protection and forestry coalition. Copyright © 2012 Elsevier Ltd. All rights reserved.

Generalized SMO algorithm for SVM-based multitask learning.

PubMed

Cai, Feng; Cherkassky, Vladimir

2012-06-01

Exploiting additional information to improve traditional inductive learning is an active research area in machine learning. In many supervised-learning applications, training data can be naturally separated into several groups, and incorporating this group information into learning may improve generalization. Recently, Vapnik proposed a general approach to formalizing such problems, known as "learning with structured data" and its support vector machine (SVM) based optimization formulation called SVM+. Liang and Cherkassky showed the connection between SVM+ and multitask learning (MTL) approaches in machine learning, and proposed an SVM-based formulation for MTL called SVM+MTL for classification. Training the SVM+MTL classifier requires the solution of a large quadratic programming optimization problem which scales as O(n(3)) with sample size n. So there is a need to develop computationally efficient algorithms for implementing SVM+MTL. This brief generalizes Platt's sequential minimal optimization (SMO) algorithm to the SVM+MTL setting. Empirical results show that, for typical SVM+MTL problems, the proposed generalized SMO achieves over 100 times speed-up, in comparison with general-purpose optimization routines.

An improved method for predicting the effects of flight on jet mixing noise

NASA Technical Reports Server (NTRS)

Stone, J. R.

1979-01-01

The NASA method (1976) for predicting the effects of flight on jet mixing noise was improved. The earlier method agreed reasonably well with experimental flight data for jet velocities up to about 520 m/sec (approximately 1700 ft/sec). The poorer agreement at high jet velocities appeared to be due primarily to the manner in which supersonic convection effects were formulated. The purely empirical supersonic convection formulation of the earlier method was replaced by one based on theoretical considerations. Other improvements of an empirical nature included were based on model-jet/free-jet simulated flight tests. The revised prediction method is presented and compared with experimental data obtained from the Bertin Aerotrain with a J85 engine, the DC-10 airplane with JT9D engines, and the DC-9 airplane with refanned JT8D engines. It is shown that the new method agrees better with the data base than a recently proposed SAE method.

Network community-based model reduction for vortical flows

NASA Astrophysics Data System (ADS)

Gopalakrishnan Meena, Muralikrishnan; Nair, Aditya G.; Taira, Kunihiko

2018-06-01

A network community-based reduced-order model is developed to capture key interactions among coherent structures in high-dimensional unsteady vortical flows. The present approach is data-inspired and founded on network-theoretic techniques to identify important vortical communities that are comprised of vortical elements that share similar dynamical behavior. The overall interaction-based physics of the high-dimensional flow field is distilled into the vortical community centroids, considerably reducing the system dimension. Taking advantage of these vortical interactions, the proposed methodology is applied to formulate reduced-order models for the inter-community dynamics of vortical flows, and predict lift and drag forces on bodies in wake flows. We demonstrate the capabilities of these models by accurately capturing the macroscopic dynamics of a collection of discrete point vortices, and the complex unsteady aerodynamic forces on a circular cylinder and an airfoil with a Gurney flap. The present formulation is found to be robust against simulated experimental noise and turbulence due to its integrating nature of the system reduction.

Digesters in traditional Persian medicine

PubMed Central

Mahmoudpour, Zeinab; Shirafkan, Hoda; Mojahedi, Morteza; Gorji, Narjes; Mozaffarpur, Seyyed Ali

2018-01-01

Background: Functional gastrointestinal diseases are common in general populations and comprise more than 40% visits to gastroenterologists. Treatment options of gastrointestinal diseases have been limited. There are a few medications for functional gastrointestinal diseases and some of medications are not available in the market or in the place where the patient lives. Traditional Persian medicine (TPM) is a branch of alternative and traditional medicine based on individual viewpoint and humoral theory, focuses on lifestyle modification and uses natural products to manage the patients. Methods: In this study, a set of compound drugs known as digesters (jawarishes) and other applications are described based on main TPM text books. Results: Jawarishes have different formulations containing various medicinal herbs used for better food digestion and improved gastric functions and also used for other disorders including reinforcing the brain, heart, liver and some therapeutic approaches. Conclusions: By reviewing medieval Persian pharmaceutical manuscripts, we can conclude that many herbs are effective in different systems of the body and improve gastric functions. Zingiber officinalis and Piper nigrum are mixed together to get various formulations. The variety of jawarishes formulations and their different clinical applications can indicate continuity of their use. PMID:29387312

Visual graph query formulation and exploration: a new perspective on information retrieval at the edge

NASA Astrophysics Data System (ADS)

Kase, Sue E.; Vanni, Michelle; Knight, Joanne A.; Su, Yu; Yan, Xifeng

2016-05-01

Within operational environments decisions must be made quickly based on the information available. Identifying an appropriate knowledge base and accurately formulating a search query are critical tasks for decision-making effectiveness in dynamic situations. The spreading of graph data management tools to access large graph databases is a rapidly emerging research area of potential benefit to the intelligence community. A graph representation provides a natural way of modeling data in a wide variety of domains. Graph structures use nodes, edges, and properties to represent and store data. This research investigates the advantages of information search by graph query initiated by the analyst and interactively refined within the contextual dimensions of the answer space toward a solution. The paper introduces SLQ, a user-friendly graph querying system enabling the visual formulation of schemaless and structureless graph queries. SLQ is demonstrated with an intelligence analyst information search scenario focused on identifying individuals responsible for manufacturing a mosquito-hosted deadly virus. The scenario highlights the interactive construction of graph queries without prior training in complex query languages or graph databases, intuitive navigation through the problem space, and visualization of results in graphical format.

Nanocrystal: a novel approach to overcome skin barriers for improved topical drug delivery.

PubMed

Patel, Viral; Sharma, Om Prakash; Mehta, Tejal

2018-04-01

Skin is an important route of drug delivery for the treatment of various dermatological conditions. The advent of nanotechnology is paving the roadmaps for topical drug delivery by providing sustained release as well as maintaining a localized effect, outweighing the toxicity concern. Area covered: This review highlighted the morphology of skin, its barrier nature as well as drug penetration pathways after topical application of formulations. The existing methods to improve topical drug delivery, by infringing or permeating the skin barriers, are discussed. This context concretes the foundation to accentuate the need for the development of nanocrystal-based topical formulation. The mechanism of drug release, immediate as well as sustained release, after topical administration of drug nanocrystals is also elaborated. The special emphasis is given on the breakthrough achieved, in topical drug delivery using drug nanocrystals, so far in the plethora of literature, patents, and products, under clinical trial as well as in the market. Expert opinion: The current research on nanocrystals for topical drug delivery is highlighting the breakthroughs achieved so far. The output of these research envisages that topical nanocrystals based formulations can be a novel strategy for the drugs which are facing solubility, bioavailability and toxicity concerns.

Polynomial Size Formulations for the Distance and Capacity Constrained Vehicle Routing Problem

NASA Astrophysics Data System (ADS)

Kara, Imdat; Derya, Tusan

2011-09-01

The Distance and Capacity Constrained Vehicle Routing Problem (DCVRP) is an extension of the well known Traveling Salesman Problem (TSP). DCVRP arises in distribution and logistics problems. It would be beneficial to construct new formulations, which is the main motivation and contribution of this paper. We focused on two indexed integer programming formulations for DCVRP. One node based and one arc (flow) based formulation for DCVRP are presented. Both formulations have O(n2) binary variables and O(n2) constraints, i.e., the number of the decision variables and constraints grows with a polynomial function of the nodes of the underlying graph. It is shown that proposed arc based formulation produces better lower bound than the existing one (this refers to the Water's formulation in the paper). Finally, various problems from literature are solved with the node based and arc based formulations by using CPLEX 8.0. Preliminary computational analysis shows that, arc based formulation outperforms the node based formulation in terms of linear programming relaxation.

Chitosan-sodium lauryl sulfate nanoparticles as a carrier system for the in vivo delivery of oral insulin.

PubMed

Elsayed, Amani; Al-Remawi, Mayyas; Qinna, Nidal; Farouk, Asim; Al-Sou'od, Khaldoun A; Badwan, Adnan A

2011-09-01

The present work explores the possibility of formulating an oral insulin delivery system using nanoparticulate complexes made from the interaction between biodegradable, natural polymer called chitosan and anionic surfactant called sodium lauryl sulfate (SLS). The interaction between chitosan and SLS was confirmed by Fourier transform infrared spectroscopy. The nanoparticles were prepared by simple gelation method under aqueous-based conditions. The nanoparticles were stable in simulated gastric fluids and could protect the encapsulated insulin from the GIT enzymes. Additionally, the in vivo results clearly indicated that the insulin-loaded nanoparticles could effectively reduce the blood glucose level in a diabetic rat model. However, additional formulation modifications are required to improve insulin oral bioavailability.

Theory of a ring laser. [electromagnetic field and wave equations

NASA Technical Reports Server (NTRS)

Menegozzi, L. N.; Lamb, W. E., Jr.

1973-01-01

Development of a systematic formulation of the theory of a ring laser which is based on first principles and uses a well-known model for laser operation. A simple physical derivation of the electromagnetic field equations for a noninertial reference frame in uniform rotation is presented, and an attempt is made to clarify the nature of the Fox-Li modes for an open polygonal resonator. The polarization of the active medium is obtained by using a Fourier-series method which permits the formulation of a strong-signal theory, and solutions are given in terms of continued fractions. It is shown that when such a continued fraction is expanded to third order in the fields, the familiar small-signal ring-laser theory is obtained.

First-principles definition and measurement of planetary electromagnetic-energy budget.

PubMed

Mishchenko, Michael I; Lock, James A; Lacis, Andrew A; Travis, Larry D; Cairns, Brian

2016-06-01

The imperative to quantify the Earth's electromagnetic-energy budget with an extremely high accuracy has been widely recognized but has never been formulated in the framework of fundamental physics. In this paper we give a first-principles definition of the planetary electromagnetic-energy budget using the Poynting-vector formalism and discuss how it can, in principle, be measured. Our derivation is based on an absolute minimum of theoretical assumptions, is free of outdated notions of phenomenological radiometry, and naturally leads to the conceptual formulation of an instrument called the double hemispherical cavity radiometer (DHCR). The practical measurement of the planetary energy budget would require flying a constellation of several dozen planet-orbiting satellites hosting identical well-calibrated DHCRs.

First-principles definition and measurement of planetary electromagnetic-energy budget

NASA Astrophysics Data System (ADS)

Mishchenko, M. I.; James, L.; Lacis, A. A.; Travis, L. D.; Cairns, B.

2016-12-01

The imperative to quantify the Earth's electromagnetic-energy budget with an extremely high accuracy has been widely recognized but has never been formulated in the framework of fundamental physics. In this talk we give a first-principles definition of the planetary electromagnetic-energy budget using the Poynting-vector formalism and discuss how it can, in principle, be measured. Our derivation is based on an absolute minimum of theoretical assumptions, is free of outdated concepts of phenomenological radiometry, and naturally leads to the conceptual formulation of an instrument called the double hemispherical cavity radiometer (DHCR). The practical measurement of the planetary energy budget would require flying a constellation of several dozen planet-orbiting satellites hosting identical well-calibrated DHCRs.

First-Principles Definition and Measurement of Planetary Electromagnetic-Energy Budget

NASA Technical Reports Server (NTRS)

Mishchenko, Michael I.; Lock, James A.; Lacis, Andrew A.; Travis, Larry D.; Cairns, Brian

2016-01-01

The imperative to quantify the Earths electromagnetic-energy budget with an extremely high accuracy has been widely recognized but has never been formulated in the framework of fundamental physics. In this paper we give a first-principles definition of the planetary electromagnetic-energy budget using the Poynting- vector formalism and discuss how it can, in principle, be measured. Our derivation is based on an absolute minimum of theoretical assumptions, is free of outdated notions of phenomenological radiometry, and naturally leads to the conceptual formulation of an instrument called the double hemispherical cavity radiometer (DHCR). The practical measurement of the planetary energy budget would require flying a constellation of several dozen planet-orbiting satellites hosting identical well-calibrated DHCRs.

Development of an integrated BEM approach for hot fluid structure interaction

NASA Technical Reports Server (NTRS)

Dargush, Gary F.; Banerjee, Prasanta K.; Honkala, Keith A.

1988-01-01

In the present work, the boundary element method (BEM) is chosen as the basic analysis tool, principally because the definition of temperature, flux, displacement and traction are very precise on a boundary-based discretization scheme. One fundamental difficulty is, of course, that a BEM formulation requires a considerable amount of analytical work, which is not needed in the other numerical methods. Progress made toward the development of a boundary element formulation for the study of hot fluid-structure interaction in Earth-to-Orbit engine hot section components is reported. The primary thrust of the program to date has been directed quite naturally toward the examination of fluid flow, since boundary element methods for fluids are at a much less developed state.

Proposed changes for part N of suggested state regulations

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

Paris, R.

1997-02-01

This paper discusses proposed changes for Part N regulations regarding naturally occuring radioactive materials. It describes the work of the Commission on NORM of the Conference of Radiation Control Program Directors (CRCPD), toward adjusting the regulations. A set of questions was formulated and a review panel established to address these questions and come back with recommended actions. The panel recommended the distinction that the material being regulated is `Technologically Enhanced Naturally Occurring Radioactive Material` (TENORM). By this they mean `naturally occurring radioactive material not regulated under the Atomic Energy Act (AEA) whose radionuclide concentrations have been increased by or asmore » a result of human practices.` Recommendations also include: using a dose based instead of concentration based standard; refined definition of exemptions from regulations; exclusion of radon from Total Effective Dose Equivalent (TEDE) calculations; provide states flexibility in implementation; inclusion of prospective remedial and operations aspects for TENORM; provision of institutional controls.« less

Long-Circulating Curcumin-Loaded Liposome Formulations with High Incorporation Efficiency, Stability and Anticancer Activity towards Pancreatic Adenocarcinoma Cell Lines In Vitro.

PubMed

Mahmud, Mohamed; Piwoni, Adriana; Filipczak, Nina; Janicka, Martyna; Gubernator, Jerzy

2016-01-01

The incorporation of hydrophobic drugs into liposomes improve their bioavailability and leads to increased stability and anticancer activity, along with decreased drug toxicity. Curcumin (Cur) is a natural polyphenol compound with a potent anticancer activity in pancreatic adenocarcinoma (PA). In the present study, different types of Cur-loaded liposomal formulations were prepared and characterized in terms of size, shape, zeta potential, optimal drug-to-lipid ratio and stability at 4°C, 37°C; and in human plasma in vitro. The best formulation in terms of these parameters was PEGylated, cholesterol-free formulation based upon hydrogenated soya PC (HSPC:DSPE-PEG2000:Cur, termed H5), which had a 0.05/10 molar ratio of drug-to-lipid, was found to be stable and had a 96% Cur incorporation efficiency. All Cur-loaded liposomal formulations had potent anticancer activity on the PA cancer cell lines AsPC-1 and BxPC-3, and were less toxic to a normal cell line (NHDF). Furthermore, apoptosis-induction induced by Cur in PA cells was associated with morphological changes including cell shrinkage, cytoplasmic blebbing, irregularity in shape and the externalization of cell membrane phosphatidylserine, which was preceded by an increase in intracellular reactive oxygen species (ROS) generation and caspase 3/7 activation. Because the liposomal formulations tested here, especially the H5 variant which exhibited slow release of the Cur in the human plasma test, the formulation may be stable enough to facilitate the accumulation of pharmacologically active amounts of Cur in target cancer tissue by EPR. Therefore, our formulations could serve as a promising therapeutic approach for pancreatic cancer and other cancers.

The Electromagnetic Conception of Nature at the Root of the Special and General Relativity Theories and its Revolutionary Meaning

NASA Astrophysics Data System (ADS)

Giannetto, Enrico R. A.

2009-06-01

The revolution in XX century physics, induced by relativity theories, had its roots within the electromagnetic conception of Nature. It was developed through a tradition related to Brunian and Leibnizian physics, to the German Naturphilosophie and English XIXth physics. The electromagnetic conception of Nature was in some way realized by the relativistic dynamics of Poincaré of 1905. Einstein, on the contrary, after some years, linked relativistic dynamics to a semi-mechanist conception of Nature. He developed general relativity theory on the same ground, but Hilbert formulated it starting from the electromagnetic conception of Nature. Here, a comparison between these two conceptions is proposed in order to understand the conceptual foundations of special relativity within the context of the changing world views. The whole history of physics as well as history of science can be considered as a conflict among different worldviews. Every theory, as well as every different formulation of a theory implies a different worldview: a particular image of Nature implies a particular image of God (atheism too has a particular image of God) as well as of mankind and of their relationship. Thus, it is very relevant for scientific education to point out which image of Nature belongs to a particular formulation of a theory, which image comes to dominate and for which ideological reason.

Open-ended formulation of self-consistent field response theory with the polarizable continuum model for solvation.

PubMed

Di Remigio, Roberto; Beerepoot, Maarten T P; Cornaton, Yann; Ringholm, Magnus; Steindal, Arnfinn Hykkerud; Ruud, Kenneth; Frediani, Luca

2016-12-21

The study of high-order absorption properties of molecules is a field of growing importance. Quantum-chemical studies can help design chromophores with desirable characteristics. Given that most experiments are performed in solution, it is important to devise a cost-effective strategy to include solvation effects in quantum-chemical studies of these properties. We here present an open-ended formulation of self-consistent field (SCF) response theory for a molecular solute coupled to a polarizable continuum model (PCM) description of the solvent. Our formulation relies on the open-ended, density matrix-based quasienergy formulation of SCF response theory of Thorvaldsen, et al., [J. Chem. Phys., 2008, 129, 214108] and the variational formulation of the PCM, as presented by Lipparini et al., [J. Chem. Phys., 2010, 133, 014106]. Within the PCM approach to solvation, the mutual solute-solvent polarization is represented by means of an apparent surface charge (ASC) spread over the molecular cavity defining the solute-solvent boundary. In the variational formulation, the ASC is an independent, variational degree of freedom. This allows us to formulate response theory for molecular solutes in the fixed-cavity approximation up to arbitrary order and with arbitrary perturbation operators. For electric dipole perturbations, pole and residue analyses of the response functions naturally lead to the identification of excitation energies and transition moments. We document the implementation of this approach in the Dalton program package using a recently developed open-ended response code and the PCMSolver libraries and present results for one-, two-, three-, four- and five-photon absorption processes of three small molecules in solution.

Efficacy of a moxidectin/triclabendazole oral formulation against mixed infections of Fasciola hepatica and gastrointestinal nematodes in sheep.

PubMed

Martínez-Valladares, M; Cordero-Pérez, C; Castañón-Ordóñez, L; Famularo, M R; Fernández-Pato, N; Rojo-Vázquez, F A

2010-11-24

We have evaluated the efficacy in sheep of a combination drench formulation at the recommended dose rate of 0.2 mg moxidectin/kg bodyweight and 10 mg triclabendazole/kg bodyweight against an experimental infection with Fasciola hepatica and a natural infection with gastrointestinal nematodes. We confirmed that the efficacy of reducing fecal egg output was 98.3% for trichostrongyle eggs and 100% for F. hepatica eggs. Based on adult worm and fluke recovery, the efficacy varied according to the target species. A reduction was found in the number of Teladorsagia circumcincta, Trichostrongylus spp., Nematodirus spp., and Trichuris spp. greater than 95%, but the efficacy for Oesophagostomum spp. varied, with values below 90%. The reduction in F. hepatica was higher than 95% for all stages. The effectiveness of the formulation was also confirmed by an increase in total proteins and albumin following treatment. Copyright © 2010 Elsevier B.V. All rights reserved.

Influence of processing parameters on morphology of polymethoxyflavone in emulsions.

PubMed

Ting, Yuwen; Li, Colin C; Wang, Yin; Ho, Chi-Tang; Huang, Qingrong

2015-01-21

Polymethoxyflavones (PMFs) are groups of compounds isolated from citrus peels that have been documented with wide arrays of health-promoting bioactivities. Because of their hydrophobic structure and high melting point, crystallized PMFs usually have poor systemic bioavailability when consumed orally. To improve the oral efficiency of PMFs, a viscoelastic emulsion system was formulated. Because of the crystalline nature, the inclusion of PMFs into the emulsion system faces great challenges in having sufficient loading capacity and stabilities. In this study, the process of optimizing the quality of emulsion-based formulation intended for PMF oral delivery was systematically studied. With alteration of the PMF loading concentration, processing temperature, and pressure, the emulsion with the desired droplet and crystal size can be effectively fabricated. Moreover, storage temperatures significantly influenced the stability of the crystal-containing emulsion system. The results from this study are a good illustration of system optimization and serve as a great reference for future formulation design of other hydrophobic crystalline compounds.

Anti-dandruff Hair Tonic Containing Lemongrass (Cymbopogon flexuosus) Oil.

PubMed

Chaisripipat, Wannee; Lourith, Nattaya; Kanlayavattanakul, Mayuree

2015-01-01

Natural remedies for treating dandruff are becoming popular. A randomized, double-blind, placebo-controlled, split-head efficacy evaluation was conducted 30 Thai volunteers aged 20-60 years experiencing dandruff measured at level 3 on D-Squame® scale. An easy to use hair tonic containing essential oil of lemongrass (Cymbopogon flexuosus) active against lipophilic yeasts was developed and then evaluated for efficacy and preference. The base formulation with the significantly highest preference (p < 0.05) was stowed with the oil at 5, 10 or 15%. Subjects applied the formulation twice a day, and an efficacy assessment with D-Squame® scale was conducted on days 7 and 14 of application. The application of lemongrass oil hair tonics with 5, 10, or 15% reduced dandruff significant (p < 0.005) at day 7 (33, 75, and 51%) and increased the effect even more (p < 0.005) at day 14 (52, 81, and 74%). The hair tonic formulation with 10% of lemongrass oil seems to be the most effective preparation. © 2015 S. Karger GmbH, Freiburg.

Nonlinear elasticity in rocks: A comprehensive three-dimensional description

DOE PAGES

Lott, Martin; Remillieux, Marcel; Garnier, Vincent; ...

2017-07-17

Here we study theoretically and experimentally the mechanisms of nonlinear and nonequilibrium dynamics in geomaterials through dynamic acoustoelasticity testing. In the proposed theoretical formulation, the classical theory of nonlinear elasticity is extended to include the effects of conditioning. This formulation is adapted to the context of dynamic acoustoelasticity testing in which a low-frequency “pump” wave induces a strain field in the sample and modulates the propagation of a high-frequency “probe” wave. Experiments are conducted to validate the formulation in a long thin bar of Berea sandstone. Several configurations of the pump and probe are examined: the pump successively consists ofmore » the first longitudinal and first torsional mode of vibration of the sample while the probe is successively based on (pressure) $P$ and (shear) $S$ waves. The theoretical predictions reproduce many features of the elastic response observed experimentally, in particular, the coupling between nonlinear and nonequilibrium dynamics and the three-dimensional effects resulting from the tensorial nature of elasticity.« less

Preliminary investigation of topical nitroglycerin formulations containing natural wound healing agent in diabetes-induced foot ulcer.

PubMed

Hotkar, Mukesh S; Avachat, Amelia M; Bhosale, Sagar S; Oswal, Yogesh M

2015-04-01

Nitroglycerin (NTG) is an organic nitrate rapidly denitrated by enzymes to release free radical nitric oxide and shows improved wound healing and tissue protection from oxidative damage. The purpose of this study was to evaluate whether topical application of NTG in the form of gel/ointment along with a natural wound healing agent, aloe vera, would bring about wound healing by using diabetes-induced foot ulcer model and rat excision wound model. All these formulations were evaluated for pH, viscosity, drug content and ex vivo diffusion studies using rat skin. Based on ex vivo permeation studies, the formulation consisting of carbopol 974p as a gelling agent and aloe vera was found to be suitable. The in vivo study used streptozotocin-induced diabetic foot ulcer and rat excision wound models to analyse wound healing activity. The wound size in animals of all treated groups was significantly reduced compared with that of the diabetic control and marketed treated animals. This study showed that the gel formed with carbopol 974p (1%) and aloe vera promotes significant wound healing and closure in diabetic rats compared with the commercial product and provides a promising product to be used in diabetes-induced foot ulcer. © 2013 The Authors. International Wound Journal © 2013 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Efficiency of Calamintha officinalis essential oil as preservative in two topical product types.

PubMed

Nostro, A; Cannatelli, M A; Morelli, I; Musolino, A D; Scuderi, F; Pizzimenti, F; Alonzo, V

2004-01-01

To verify the efficiency of Calamintha officinalis essential oil as natural preservative in two current formulations. The 1.0 and 2.0% (v/v) C. officinalis essential oil was assayed for its preservative activity in two product types (cream and shampoo). The microbial challenge test was performed following the standards proposed by the European Pharmacopoeia Commission (E.P.) concerning topical preparations using standard micro-organisms and in addition wild strains, either in single or mixed cultures were used. The results clearly demonstrated that the C. officinalis essential oil at 2.0% concentration reduced the microbial inoculum satisfying the criterion A of the E.P. in the cream formulation and the criterion B in the shampoo formulation. Standard and wild strains showed a behaviour similar, both in cream and in shampoo formulation, with no significant difference (gerarchic variance, P > 0.05). C. officinalis essential oil confirmed its preservative properties but at higher concentration than that shown in previous studies on cetomacrogol cream. The nature of the formulation in which an essential oil is incorporated as preservative could have considerable effect on its efficacy.

Efficacy of Candida sake CPA-1 formulation for controlling Penicillium expansum decay on pome fruit from different Mediterranean regions.

PubMed

Torres, R; Teixidó, N; Viñas, I; Mari, M; Casalini, L; Giraud, M; Usall, J

2006-11-01

The effectiveness of a formulated product of the yeast Candida sake CPA-1 for controlling postharvest diseases on pome fruits was demonstrated in laboratory, semicommercial, and commercial trials carried out in the major pome fruit producing region of the European Union. First, one wettable powder and seven liquid formulations were tested in laboratory trials that involved two varieties of apples and two varieties of pears. In all cases, an efficacy similar to that of fresh cells was demonstrated in the control of artificial Penicillium expansum infection. After these trials, the formulated product chosen for semicommercial and commercial trials was LF1, a liquid formulation that is particularly suitable for commercial applications. In semicommercial trials, LF1 showed a performance similar to fresh cells in most trials, and the population dynamics of both fresh and formulated cells were quite stable throughout the storage period. This indicates the high viability of C. sake CPA-1 in this formulation and the absence of adverse effects during the formulation of the product, which may significantly affect both its ability to grow on fruit and its antagonistic activity. We evaluated the control of natural infection after applying the formulated product in a commercial drencher in different packinghouses. A significant reduction in the incidence of diseases was observed with a recommended dose of around 10(7) CFU/ml when natural infections were greater than 1%. In general, large quantities of yeast were observed on the surface of unwounded fruits of different pome fruit cultivars. Moreover, populations of this biocontrol agent increased rapidly on fruit surfaces and remained quite stable for a long time under commercial storage conditions. Commercial practices used in packinghouses were therefore successfully applied for this formulated product.

Application of electrochemical impedance spectroscopy: A phase behavior study of babassu biodiesel-based microemulsions.

PubMed

Pereira, Thulio C; Conceição, Carlos A F; Khan, Alamgir; Fernandes, Raquel M T; Ferreira, Maira S; Marques, Edmar P; Marques, Aldaléa L B

2016-11-05

Microemulsions are thermodynamically stable systems of two immiscible liquids, one aqueous and the other of organic nature, with a surfactant and/or co-surfactant adsorbed in the interface between the two phases. Biodiesel-based microemulsions, consisting of alkyl esters of fatty acids, open a new means of analysis for the application of electroanalytical techniques, and is advantageous as it eliminates the required pre-treatment of a sample. In this work, the phase behaviours of biodiesel-based microemulsions were investigated through the electrochemical impedance spectroscopy (EIS) technique. We observed thatan increase in the amount of biodiesel in the microemulsion formulation increases the resistance to charge transfer at the interface. Also, the electrical conductivity measurements revealed that a decrease or increase in electrical properties depends on the amount of biodiesel. EIS studies of the biodiesel-based microemulsion samples showed the presence of two capacitive arcs: one high-frequency and the other low-frequency. Thus, the formulation of microemulsions plays an important role in estimating the electrical properties through the electrochemical impedance spectroscopy technique. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of electrochemical impedance spectroscopy: A phase behavior study of babassu biodiesel-based microemulsions

NASA Astrophysics Data System (ADS)

Pereira, Thulio C.; Conceição, Carlos A. F.; Khan, Alamgir; Fernandes, Raquel M. T.; Ferreira, Maira S.; Marques, Edmar P.; Marques, Aldaléa L. B.

2016-11-01

Microemulsions are thermodynamically stable systems of two immiscible liquids, one aqueous and the other of organic nature, with a surfactant and/or co-surfactant adsorbed in the interface between the two phases. Biodiesel-based microemulsions, consisting of alkyl esters of fatty acids, open a new means of analysis for the application of electroanalytical techniques, and is advantageous as it eliminates the required pre-treatment of a sample. In this work, the phase behaviours of biodiesel-based microemulsions were investigated through the electrochemical impedance spectroscopy (EIS) technique. We observed thatan increase in the amount of biodiesel in the microemulsion formulation increases the resistance to charge transfer at the interface. Also, the electrical conductivity measurements revealed that a decrease or increase in electrical properties depends on the amount of biodiesel. EIS studies of the biodiesel-based microemulsion samples showed the presence of two capacitive arcs: one high-frequency and the other low-frequency. Thus, the formulation of microemulsions plays an important role in estimating the electrical properties through the electrochemical impedance spectroscopy technique.

Variational Principles for Buckling of Microtubules Modeled as Nonlocal Orthotropic Shells

PubMed Central

2014-01-01

A variational principle for microtubules subject to a buckling load is derived by semi-inverse method. The microtubule is modeled as an orthotropic shell with the constitutive equations based on nonlocal elastic theory and the effect of filament network taken into account as an elastic surrounding. Microtubules can carry large compressive forces by virtue of the mechanical coupling between the microtubules and the surrounding elastic filament network. The equations governing the buckling of the microtubule are given by a system of three partial differential equations. The problem studied in the present work involves the derivation of the variational formulation for microtubule buckling. The Rayleigh quotient for the buckling load as well as the natural and geometric boundary conditions of the problem is obtained from this variational formulation. It is observed that the boundary conditions are coupled as a result of nonlocal formulation. It is noted that the analytic solution of the buckling problem for microtubules is usually a difficult task. The variational formulation of the problem provides the basis for a number of approximate and numerical methods of solutions and furthermore variational principles can provide physical insight into the problem. PMID:25214886

A contact layer element for large deformations

NASA Astrophysics Data System (ADS)

Weißenfels, C.; Wriggers, P.

2015-05-01

In many contact situations the material behavior of one contact member strongly influences the force acting between the two bodies. Unfortunately standard friction models cannot reproduce all of these material effects at the contact layer and often continuum interface elements are used instead. These elements are intrinsically tied to the fixed grid and hence cannot be used in large sliding simulations. Due to the shortcomings of the standard contact formulations and of the interface elements a new type of a contact layer element is developed in this work. The advantages of this element are the direct implementation of continuum models into the contact formulation and the application to arbitrary large deformations. Showing a relation between continuum and contact kinematics based on the solid-shell concept the new contact element is at the end a natural extension of the standard contact formulations into 3D. Two examples show that the continuum behavior can be exactly reproduced at the contact surface even in large sliding situations using this contact layer element. For the discretization of the new contact element the Mortar method is chosen exemplary, but it can be combined with all kinds of contact formulations.

Emollient product design: objective measurements of formulation structure, texture and performance, and subjective assessments of user acceptability.

PubMed

Antonijević, M D; Owusu-Ware, S; Sanchon-Lopez, B

2018-06-01

The choice of prescribed emollients is usually based on cost and patient preference. Differences in formulations can affect user acceptability. To compare the physical performance, user acceptability and various product design features of two emollient gels that are prescribed in the UK and alleged to be therapeutically interchangeable because their formulations are described as having the same contents of oily ingredients. We found that here are in fact significant measurable differences between the structure and performance of the two formulations, which materially affect their user acceptability. These differences are attributed to the use of different types of gelling agents and other ingredients of differing grades/quality and concentrations, and probably due to the formulations being made by different manufacturing processes. We also identified other product design features that are important to user appeal, including the type of container in which the formulations are presented, the type of dispensing devices provided, and the nature and form of the supplied user instructions. Patients and prescribers should be aware that there can be important differences in performance and user appeal between emollients, even between products that, superficially, may appear to be very similar. These important performance aspects should be characterized for new emollient introductions to encourage better informed product selection. © 2018 The Authors. Clinical and Experimental Dermatology published by John Wiley & Sons Ltd on behalf of British Association of Dermatologists, North American Clinical Dermatologic Society and St Johns Dermatological Society.

Managing the rippling stream: decisionmaking in natural resource administration

USGS Publications Warehouse

Doerksen, Harvey R.; Lamb, Berton L.

1979-01-01

This article addresses the conflict which exists within the water resources decisionmaking arena over the allocation of water for instream uses. The discussion reviews the literature on public administration regarding decisionmaking, and is based on research performed by the authors which synthesizes a model of decisionmaking. This model can be used as both a description of agency behavior, and as the basis for developing a prescription for strategy formulation.

Perfume formulation: words and chats.

PubMed

Ellena, Céline

2008-06-01

What does it mean to create fragrances with materials from chemistry and/or from nature? How are they used to display their characteristic differences, their own personality? Is it easier to create with synthetic raw materials or with essential oils? This review explains why a perfume formulation corresponds in fact to a conversation, an interplay between synthetic and natural perfumery materials. A synthetic raw material carries a single information, and usually is very linear. Its smell is uniform, clear, and faithful. Natural raw materials, on the contrary, provide a strong, complex and generous image. While a synthetic material can be seen as a single word, a natural one such as rose oil could be compared to chatting: cold, warm, sticky, heavy, transparent, pepper, green, metallic, smooth, watery, fruity... full of information. Yet, if a very small amount of the natural material is used, nothing happens, the fragrance will not change. However, if a large amount is used, the rose oil will swallow up everything else. The fragrance will smell of nothing else except rose! To formulate a perfume is not to create a culinary recipe, with only dosing the ingredients in well-balanced amounts. To formulate rather means to flexibly knit materials together with a lively stitch, meeting or repelling each other, building a pleasant form, which is neither fixed, nor solid, nor rigid. A fragrance has an overall structure, which ranges from a clear sound, made up of stable, unique, and linear items, to a background chat, comfortable and reassuring. But that does, of course, not mean that there is only one way of creating a fragrance!

Ocimum Sanctum seeds, a natural superdisintegrant: formulation and evaluation of fast melt tablets of nimesulide.

PubMed

Malik, Karan; Arora, Gurpreet; Singh, Inderbir

2012-01-01

Fast melt tablets, also known as fast dissolving tablets, disintegrate instantaneously within the mouth and thus can be consumed without water. The present study was aimed to formulate fast melt tablets of nimesulide by using Ocimum Sanctum seeds as a natural tablet superdisintegrant. Powdered Ocimum seeds were characterized for powder flow properties (bulk density, tapped density, Carr's consolidation index, Hausner ratio, angle of repose), swelling index, viscosity, pH, loss on drying and microbial load. The prepared tablets were evaluated for different tablet parametric tests, wetting time, water absorption ratio, effective pore radius, porosity, packing fraction, in vitro and in vivo disintegration time, in-vitro dissolution and stability studies. The swelling index was evaluated to be 1600. An appreciable effect of the natural material was seen on tablet hardness and friability. The water absorption ratio increased from 56.15 +/- 0.85 to 80.76 +/- 0.70 (A1-A4). Water uptake coupled natural polymer swelling could be the most probable mechanism for concentration dependent reduction in disintegration time by the Ocimum Sanctum seeds. Porosity of the formulated tablets was found to increase from batch A1-A4. The in vitro disintegration results were in line with in vivo disintegration results. The f2 values (in comparison with Nimulid MD) of 95.90 and 93.65 were obtained with A3 and A4 batches respectively. It could be concluded that Ocimum Sanctum seeds could be used as a natural superdisintegrant in the formulation of fast melt tablets.

On the nature of control algorithms for free-floating space manipulators

NASA Technical Reports Server (NTRS)

Papadopoulos, Evangelos; Dubowsky, Steven

1991-01-01

It is suggested that nearly any control algorithm that can be used for fixed-based manipulators also can be employed in the control of free-floating space manipulator systems, with the additional conditions of estimating or measuring a spacecraft's orientation and of avoiding dynamic singularities. This result is based on the structural similarities between the kinematic and dynamic equations for the same manipulator but with a fixed base. Barycenters are used to formulate the kinematic and dynamic equations of free-floating space manipulators. A control algorithm for a space manipulator system is designed to demonstrate the value of the analysis.

Turbulence and fire-spotting effects into wild-land fire simulators

NASA Astrophysics Data System (ADS)

Kaur, Inderpreet; Mentrelli, Andrea; Bosseur, Frédéric; Filippi, Jean-Baptiste; Pagnini, Gianni

2016-10-01

This paper presents a mathematical approach to model the effects and the role of phenomena with random nature such as turbulence and fire-spotting into the existing wildfire simulators. The formulation proposes that the propagation of the fire-front is the sum of a drifting component (obtained from an existing wildfire simulator without turbulence and fire-spotting) and a random fluctuating component. The modelling of the random effects is embodied in a probability density function accounting for the fluctuations around the fire perimeter which is given by the drifting component. In past, this formulation has been applied to include these random effects into a wildfire simulator based on an Eulerian moving interface method, namely the Level Set Method (LSM), but in this paper the same formulation is adapted for a wildfire simulator based on a Lagrangian front tracking technique, namely the Discrete Event System Specification (DEVS). The main highlight of the present study is the comparison of the performance of a Lagrangian and an Eulerian moving interface method when applied to wild-land fire propagation. Simple idealised numerical experiments are used to investigate the potential applicability of the proposed formulation to DEVS and to compare its behaviour with respect to the LSM. The results show that DEVS based wildfire propagation model qualitatively improves its performance (e.g., reproducing flank and back fire, increase in fire spread due to pre-heating of the fuel by hot air and firebrands, fire propagation across no fuel zones, secondary fire generation, ...) when random effects are included according to the present formulation. The performance of DEVS and LSM based wildfire models is comparable and the only differences which arise among the two are due to the differences in the geometrical construction of the direction of propagation. Though the results presented here are devoid of any validation exercise and provide only a proof of concept, they show a strong inclination towards an intended operational use. The existing LSM or DEVS based operational simulators like WRF-SFIRE and ForeFire respectively can serve as an ideal basis for the same.

Managing Occupational Irritant Contact Dermatitis Using a Two-Step Skincare Regimen Designed to Prevent Skin Damage and Support Skin Recovery.

PubMed

von Grote, Erika C; Palaniswarmy, Kiruthi; Meckfessel, Matthew H

2016-12-01

Occupational irritant contact dermatitis (ICD) affecting the hands is a common and difficult-to-manage condition. Occupations that necessitate contact with harsh chemicals, use of alcohol-based disinfectants, and frequent hand washing elevate the risk of ICD. Management strategies that do not adequately prevent accumulated damage and repair skin, can develop into chronic dermatoses which negatively impact work productivity and quality of life. A 2-step skin-care regimen (Excipial Daily Protection Hand Cream (EP) and Excipial Rapid Repair Hand Cream (ER), Galderma Laboratories, L.P.) has been developed as a daily-use management strategy to protect and repair vulnerable hands. The protective barrier cream is formulated with aluminum chlorohydrate and designed for pre-exposure application to enhance the skin's natural protective barrier and minimize excessive moisture while wearing protective gloves. The repair cream, a lipid-rich formulation, is intended for post-exposure application to rehydrate and facilitate the skin's natural healing process. The results of 3 clinical studies highlighted in this review demonstrate how the use of a 2-step skin-care regimen offers a greater protective effect against ICD than the use of barrier cream alone, and also how the formulation of the barrier cream used in these studies helps minimize the occlusion effect caused by gloves and does not interfere with the antibacterial efficacy of an alcohol-based hand sanitizer. This 2-step skin-care regimen is effectively designed to manage and minimize the risk of ICD development in a variety of patients and provides clinicians an additional tool for helping patients manage ICD. J Drugs Dermatol. 2016;15(12):1504-1510.

Thermodynamic model of natural, medieval and nuclear waste glass durability

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

Jantzen, C.M.; Plodinec, M.J.

1983-01-01

A thermodynamic model of glass durability based on hydration of structural units has been applied to natural glass, medieval window glasses, and glasses containing nuclear waste. The relative durability predicted from the calculated thermodynamics correlates directly with the experimentally observed release of structural silicon in the leaching solution in short-term laboratory tests. By choosing natural glasses and ancient glasses whose long-term performance is known, and which bracket the durability of waste glasses, the long-term stability of nuclear waste glasses can be interpolated among these materials. The current Savannah River defense waste glass formulation is as durable as natural basalt frommore » the Hanford Reservation (10/sup 6/ years old). The thermodynamic hydration energy is shown to be related to the bond energetics of the glass. 69 references, 2 figures, 1 table.« less

Why morphology matters in birds and UAV's: How scale affects attitude wind sensitivity

NASA Astrophysics Data System (ADS)

Gamble, L. L.; Inman, D. J.

2017-11-01

Although natural fliers have been shown to morph their geometry to adapt to unfavorable wind loading, there exists heavy skepticism within the aviation community regarding the benefits and necessity of morphing aircraft technology. Here, we develop a vector derivation that characterizes how high winds affect the overall flight velocity and sideslip for both natural and manmade fliers. This derivation is formulated in such a way that only a single non-dimensional velocity parameter is needed to quantify the response. We show mathematically that in high winds, low-altitude fliers are more prone to substantial changes in the sideslip angle, struggle to maintain gliding velocity, and experience five times the peak sideslip sensitivity when compared to high-altitude fliers. In order to counteract these adverse changes, low-altitude fliers require a high degree of controllability which can be achieved through extreme morphological changes. The results presented here highlight the importance of integrating morphing concepts into future low-altitude aircraft designs and provide a formulation to help designers decide whether or not to pursue adaptive morphing technology based on a single readily determinable parameter.

Hierarchic Extensions in the Static and Dynamic Analysis of Elastic Beams. Ph.D. Thesis, 1990 Final Report, May 1990

NASA Technical Reports Server (NTRS)

Watson, Robert A.

1991-01-01

Approximate solutions of static and dynamic beam problems by the p-version of the finite element method are investigated. Within a hierarchy of engineering beam idealizations, rigorous formulations of the strain and kinetic energies for straight and circular beam elements are presented. These formulations include rotating coordinate system effects and geometric nonlinearities to allow for the evaluation of vertical axis wind turbines, the motivating problem for this research. Hierarchic finite element spaces, based on extensions of the polynomial orders used to approximate the displacement variables, are constructed. The developed models are implemented into a general purpose computer program for evaluation. Quality control procedures are examined for a diverse set of sample problems. These procedures include estimating discretization errors in energy norm and natural frequencies, performing static and dynamic equilibrium checks, observing convergence for qualities of interest, and comparison with more exacting theories and experimental data. It is demonstrated that p-extensions produce exponential rates of convergence in the approximation of strain energy and natural frequencies for the class of problems investigated.

Longitudinal Mediation Analysis with Time-varying Mediators and Exposures, with Application to Survival Outcomes

PubMed Central

Zheng, Wenjing; van der Laan, Mark

2017-01-01

In this paper, we study the effect of a time-varying exposure mediated by a time-varying intermediate variable. We consider general longitudinal settings, including survival outcomes. At a given time point, the exposure and mediator of interest are influenced by past covariates, mediators and exposures, and affect future covariates, mediators and exposures. Right censoring, if present, occurs in response to past history. To address the challenges in mediation analysis that are unique to these settings, we propose a formulation in terms of random interventions based on conditional distributions for the mediator. This formulation, in particular, allows for well-defined natural direct and indirect effects in the survival setting, and natural decomposition of the standard total effect. Upon establishing identifiability and the corresponding statistical estimands, we derive the efficient influence curves and establish their robustness properties. Applying Targeted Maximum Likelihood Estimation, we use these efficient influence curves to construct multiply robust and efficient estimators. We also present an inverse probability weighted estimator and a nested non-targeted substitution estimator for these parameters. PMID:29387520

Cartan gravity, matter fields, and the gauge principle

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

Westman, Hans F., E-mail: hwestman74@gmail.com; Zlosnik, Tom G., E-mail: t.zlosnik@imperial.ac.uk

Gravity is commonly thought of as one of the four force fields in nature. However, in standard formulations its mathematical structure is rather different from the Yang–Mills fields of particle physics that govern the electromagnetic, weak, and strong interactions. This paper explores this dissonance with particular focus on how gravity couples to matter from the perspective of the Cartan-geometric formulation of gravity. There the gravitational field is represented by a pair of variables: (1) a ‘contact vector’ V{sup A} which is geometrically visualized as the contact point between the spacetime manifold and a model spacetime being ‘rolled’ on top ofmore » it, and (2) a gauge connection A{sub μ}{sup AB}, here taken to be valued in the Lie algebra of SO(2,3) or SO(1,4), which mathematically determines how much the model spacetime is rotated when rolled. By insisting on two principles, the gauge principle and polynomial simplicity, we shall show how one can reformulate matter field actions in a way that is harmonious with Cartan’s geometric construction. This yields a formulation of all matter fields in terms of first order partial differential equations. We show in detail how the standard second order formulation can be recovered. In particular, the Hodge dual, which characterizes the structure of bosonic field equations, pops up automatically. Furthermore, the energy–momentum and spin-density three-forms are naturally combined into a single object here denoted the spin-energy–momentum three-form. Finally, we highlight a peculiarity in the mathematical structure of our first-order formulation of Yang–Mills fields. This suggests a way to unify a U(1) gauge field with gravity into a SO(1,5)-valued gauge field using a natural generalization of Cartan geometry in which the larger symmetry group is spontaneously broken down to SO(1,3)×U(1). The coupling of this unified theory to matter fields and possible extensions to non-Abelian gauge fields are left as open questions. -- Highlights: •Develops Cartan gravity to include matter fields. •Coupling to gravity is done using the standard gauge prescription. •Matter actions are manifestly polynomial in all field variables. •Standard equations recovered on-shell for scalar, spinor and Yang–Mills fields. •Unification of a U(1) field with gravity based on the orthogonal group SO(1,5)« less

Noniterative implicit method for tracking particles in mixed Lagrangian-Eulerian formulations

NASA Technical Reports Server (NTRS)

Shih, T. I.-P.; Dasgupta, A.

1993-01-01

The existing implicit methods for the current initial value problems (IVPs) concerning particle-laden flows are complicated and iterative in nature. This paper presents a noniterative implicit method which can be used with pressure-based as well as with density-based algorithms. The method is illustrated by analyzing a dilute dispersion of noninteracting solid particles in an isothermal flow in a passage bounded by one straight wall and one wavy wall, in which all particles are spherical and have a finite velociy relative to the continuum phase at the inflow boundary.

Rotor dynamic simulation and system identification methods for application to vacuum whirl data

NASA Technical Reports Server (NTRS)

Berman, A.; Giansante, N.; Flannelly, W. G.

1980-01-01

Methods of using rotor vacuum whirl data to improve the ability to model helicopter rotors were developed. The work consisted of the formulation of the equations of motion of elastic blades on a hub using a Galerkin method; the development of a general computer program for simulation of these equations; the study and implementation of a procedure for determining physical parameters based on measured data; and the application of a method for computing the normal modes and natural frequencies based on test data.

Efficient Solution of Three-Dimensional Problems of Acoustic and Electromagnetic Scattering by Open Surfaces

NASA Technical Reports Server (NTRS)

Turc, Catalin; Anand, Akash; Bruno, Oscar; Chaubell, Julian

2011-01-01

We present a computational methodology (a novel Nystrom approach based on use of a non-overlapping patch technique and Chebyshev discretizations) for efficient solution of problems of acoustic and electromagnetic scattering by open surfaces. Our integral equation formulations (1) Incorporate, as ansatz, the singular nature of open-surface integral-equation solutions, and (2) For the Electric Field Integral Equation (EFIE), use analytical regularizes that effectively reduce the number of iterations required by iterative linear-algebra solution based on Krylov-subspace iterative solvers.

A generalized multi-dimensional mathematical model for charging and discharging processes in a supercapacitor

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

Allu, Srikanth; Velamur Asokan, Badri; Shelton, William A

A generalized three dimensional computational model based on unied formulation of electrode- electrolyte-electrode system of a electric double layer supercapacitor has been developed. The model accounts for charge transport across the solid-liquid system. This formulation based on volume averaging process is a widely used concept for the multiphase ow equations ([28] [36]) and is analogous to porous media theory typically employed for electrochemical systems [22] [39] [12]. This formulation is extended to the electrochemical equations for a supercapacitor in a consistent fashion, which allows for a single-domain approach with no need for explicit interfacial boundary conditions as previously employed ([38]).more » In this model it is easy to introduce the spatio-temporal variations, anisotropies of physical properties and it is also conducive for introducing any upscaled parameters from lower length{scale simulations and experiments. Due to the irregular geometric congurations including porous electrode, the charge transport and subsequent performance characteristics of the super-capacitor can be easily captured in higher dimensions. A generalized model of this nature also provides insight into the applicability of 1D models ([38]) and where multidimensional eects need to be considered. In addition, simple sensitivity analysis on key input parameters is performed in order to ascertain the dependence of the charge and discharge processes on these parameters. Finally, we demonstarted how this new formulation can be applied to non-planar supercapacitors« less

Effects of glyphosate acid and the glyphosate-commercial formulation (Roundup) on Dimorphandra wilsonii seed germination: Interference of seed respiratory metabolism.

PubMed

Gomes, Marcelo Pedrosa; da Silva Cruz, Fernanda Vieira; Bicalho, Elisa Monteze; Borges, Felipe Viègas; Fonseca, Marcia Bacelar; Juneau, Philippe; Garcia, Queila Souza

2017-01-01

Glyphosate-formulations are widely used in the Brazilian Cerrado (neotropical savanna) with little or no control, threatening population of the endangered species Dimorphandra wilsonii. We investigated the toxicity of different concentrations (0, 5, 25 and 50 mg l -1 ) of glyphosate acid and one of its formulations (Roundup ® ) on seed germination in D. wilsonii. Glyphosate acid and Roundup drastically decreased seed germination by decreasing seed respiration rates. The activation of antioxidant enzymes, ascorbate peroxidase and catalase assure no hydrogen peroxide accumulation in exposed seeds. Glyphosate acid and the Roundup-formulation negatively affected the activities of enzymes associated with the mitochondrial electron transport chain (ETC), with Complex III as its precise target. The toxicity of Roundup-formulation was greater than that of glyphosate acid due to its greater effects on respiration. The herbicide glyphosate must impair D. wilsonii seed germination by disrupting the mitochondrial ETC, resulting in decreased energy (ATP) production. Our results therefore indicate the importance of avoiding (or closely regulating) the use of glyphosate-based herbicides in natural Cerrado habitats of D. wilsonni as they are toxic to seed germination and therefore threaten conservation efforts. It will likewise be important to investigate the effects of glyphosate on the seeds of other species and to investigate the impacts of these pesticides elsewhere in the world. Copyright © 2016 Elsevier Ltd. All rights reserved.

FORMULATION AND EVALUATION OF RICE BRAN WAX AS OINTMENT BASE

PubMed Central

Bhalekar, M; Manish, Lavhale; Krishna, Sini

2004-01-01

Rice Bran wax is obtained from natural sources and is abundantly available in the country. Rice bran wax is suitable for use in chocolate enrobes, as an enteric coating for candy and lozenges, as a plasticizing material in chewing gums etc. Present study attempts to find if rice bran wax is useful as ointment base. The oleaginous type ointment base is prepared by using rice bran wax and evaluated for speardabililty, water number and active ingredient diffusibility. The results obtained in the present study indicate, rice bran wax can be used as a good component in ointment base, comparable with white wax. PMID:22557151

Characterization of natural polymers from jackfruit pulp, calendula flowers and tara seeds as mucoadhesive and controlled release components in buccal tablets.

PubMed

Sabale, Vidya; Paranjape, Archana; Patel, Vandana; Sabale, Prafulla

2017-02-01

Identification and physiochemical parameters such as solubility, loss on drying, viscosity, pH, swelling index, starch and gum constituents were determined in natural polymers and showed satisfactory results. Spectral studies established the compatibility of natural polymers. The drug release kinetics in preliminary trial batches showed that tablets containing natural mucilages and gum showed a prolonged drug release comparable to Carbopol 974P and Methocel K4M. Also, all tablets showed a satisfactory drug permeability flux. Acute toxicity studies confirmed the safety of natural polymers. Using response surface method supported by 2 3 factorial design, the optimized buccoadhesive tablets (C1) with drug release at 8h (R8h, %) of 53.48±0.048% showed controlled release over ≥8h and followed the Korsmeyer-Peppas model with anomalous (non-Fickian) diffusion mechanism. Mucoadhesive strength was found to be 42.71±0.49g. Comparative dissolution study between prepared and marketed formulation showed that there was no significant difference in drug release profile having similarity factor 82.97. In vivo study for optimized formulation of the buccoadhesive tablets showed the better absolute bioavailability (71.26%) against the oral solution (51.22%). Histological study confirmed non-irritant nature and stability study indicated stability of the formulation. Copyright © 2016 Elsevier B.V. All rights reserved.

Recycling of inorganic waste in monolithic and cellular glass‐based materials for structural and functional applications

PubMed Central

Rincón, Acacio; Marangoni, Mauro; Cetin, Suna

2016-01-01

Abstract The stabilization of inorganic waste of various nature and origin, in glasses, has been a key strategy for environmental protection for the last decades. When properly formulated, glasses may retain many inorganic contaminants permanently, but it must be acknowledged that some criticism remains, mainly concerning costs and energy use. As a consequence, the sustainability of vitrification largely relies on the conversion of waste glasses into new, usable and marketable glass‐based materials, in the form of monolithic and cellular glass‐ceramics. The effective conversion in turn depends on the simultaneous control of both starting materials and manufacturing processes. While silica‐rich waste favours the obtainment of glass, iron‐rich wastes affect the functionalities, influencing the porosity in cellular glass‐based materials as well as catalytic, magnetic, optical and electrical properties. Engineered formulations may lead to important reductions of processing times and temperatures, in the transformation of waste‐derived glasses into glass‐ceramics, or even bring interesting shortcuts. Direct sintering of wastes, combined with recycled glasses, as an example, has been proven as a valid low‐cost alternative for glass‐ceramic manufacturing, for wastes with limited hazardousness. The present paper is aimed at providing an up‐to‐date overview of the correlation between formulations, manufacturing technologies and properties of most recent waste‐derived, glass‐based materials. © 2016 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. PMID:27818564

Recycling of inorganic waste in monolithic and cellular glass-based materials for structural and functional applications.

PubMed

Rincón, Acacio; Marangoni, Mauro; Cetin, Suna; Bernardo, Enrico

2016-07-01

The stabilization of inorganic waste of various nature and origin, in glasses, has been a key strategy for environmental protection for the last decades. When properly formulated, glasses may retain many inorganic contaminants permanently, but it must be acknowledged that some criticism remains, mainly concerning costs and energy use. As a consequence, the sustainability of vitrification largely relies on the conversion of waste glasses into new, usable and marketable glass-based materials, in the form of monolithic and cellular glass-ceramics. The effective conversion in turn depends on the simultaneous control of both starting materials and manufacturing processes. While silica-rich waste favours the obtainment of glass, iron-rich wastes affect the functionalities, influencing the porosity in cellular glass-based materials as well as catalytic, magnetic, optical and electrical properties. Engineered formulations may lead to important reductions of processing times and temperatures, in the transformation of waste-derived glasses into glass-ceramics, or even bring interesting shortcuts. Direct sintering of wastes, combined with recycled glasses, as an example, has been proven as a valid low-cost alternative for glass-ceramic manufacturing, for wastes with limited hazardousness. The present paper is aimed at providing an up-to-date overview of the correlation between formulations, manufacturing technologies and properties of most recent waste-derived, glass-based materials. © 2016 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Skin Penetration Enhancement by Natural Oils for Dihydroquercetin Delivery.

PubMed

Čižinauskas, Vytis; Elie, Nicolas; Brunelle, Alain; Briedis, Vitalis

2017-09-12

Natural oils are commonly used in topical pharmaceutical formulations as emulsifiers, stabilizers or solubility enhancers. They are presented as safe and inert components, mainly used for formulation purposes. It is confirmed that natural oils can affect the skin penetration of various substances. Fatty acids are mainly responsible for this effect. Current understanding lacks reliable scientific data on penetration of natural oils into the skin and their skin penetration enhancement potential. In the current study, fatty acid content analysis was used to determine the principal fatty acids in soybean, olive, avocado, sea-buckthorn pulp, raspberry seed and coconut oils. Time of flight secondary ion mass spectrometry bioimaging was used to determine the distribution of these fatty acids in human skin ex vivo after application of the oils. Skin penetration enhancement ratios were determined for a perspective antioxidant compound dihydroquercetin. The results demonstrated skin penetration of fatty acids from all oils tested. Only soybean and olive oils significantly increased the skin distribution of dihydroquercetin and can be used as skin penetration enhancers. However, no correlation can be determined between the fatty acids' composition and skin penetration enhancement using currently available methodological approaches. This indicates that potential chemical penetration enhancement should be evaluated during formulation of topically applied products containing natural oils.

Visual images in Luigi Galvani's path to animal electricity.

PubMed

Piccolino, Marco

2008-01-01

The scientific endeavor that led Luigi Galvani to his hypothesis of "animal electricity," i.e., of an electricity present in a condition of disequilibrium between the interior and the exterior of excitable animal fibers, is reviewed here with particular emphasis to the role played by visual images in Galvani's path of discovery. In 1791 Galvani formulated his model of neuromuscular physiology on the base of the image of a muscle and a nerve fiber together as in a "minute animal Leyden jar." This was the last instance of a series of physical models that accompanied Galvani's experimental efforts in the search of a theory capable of accounting for the electric nature of nerve conduction in spite of the many objections formulated in the eighteenth century against a possible role of electricity in animal physiology.

Design and evaluation of novel topical formulation with olive oil as natural functional active.

PubMed

Mota, Ana Henriques; Silva, Catarina Oliveira; Nicolai, Marisa; Baby, André; Palma, Lídia; Rijo, Patrícia; Ascensão, Lia; Reis, Catarina Pinto

2017-07-03

Currently, the innovative skin research is focused on the development of novel topical formulations loaded with natural functional actives. The health benefits of olive oil are unsurpassed and many others are revealed as research studies allow the understanding of its unlimited properties. Olive oil has a protective toning effect on skin, but it is not transported effectively into its layers. Aiming the development of a cosmetic formulation for skin photoprotection and hydration, we have prepared and characterized macro-sized particles, made of a hydrogel polymer, loaded with olive oil. Alginate beads were uniform in shape, with minimal oil leakage, offering interesting prospects for encapsulation of lipophilic and poorly stable molecules, like olive oil. In vitro photoprotection and in vivo tolerance tests were in favor of this application. Thus, this study suggests that the incorporation of the olive oil-loaded particles into a cream formulation provides strong moisturizing properties and a photoprotective potential, when applied to healthy subjects.

Tunisian date (Phoenix dactylifera L.) by-products: Characterization and potential effects on sensory, textural and antioxidant properties of dairy desserts.

PubMed

Jridi, Mourad; Souissi, Nabil; Salem, Marwa Ben; Ayadi, M A; Nasri, Moncef; Azabou, Samia

2015-12-01

Three Tunisian date varieties, Deglet Nour, Kentichi and Allig, served to produce syrups and powders, which were then examined for their physico-chemical composition and antioxidant properties. Different proportions of these sweetening-like agents were incorporated to produce nine different formulations of dairy desserts, with lower amount of added sugars to avoid any artificial flavoring or coloring agents. Sensory and color evaluation data revealed that incorporating Deglet Nour and Kentichi syrup offers the most desirable formulation. Furthermore, syrup polysaccharides and fibers contribute to better maintain the final product texture. In addition, date by-products create a good source of natural thickening agents, involved in enhancing apparent viscosity and spontaneous exudation. Thanks to their high content in phenolic compounds, date by-products considerably improve antioxidant activities of the formulated desserts. Therefore, they could be valued as natural ingredients in the formulation of novel dairy products with high nutritional-properties. Copyright © 2015 Elsevier Ltd. All rights reserved.

Release of a Wound-healing Agent from PLGA Microspheres in a Thermosensitive Gel

DTIC Science & Technology

2013-01-01

have been associated with infectious complications due to the nature of wounding, giving rise to significant devitalized tissue, con- tamination of...Command, Military Infectious Dis- eases, and Combat Casualty Care Research Directorates. References [1] C. K. Murray, “ Infectious disease complications...pluronic-based metronidazole in situ gelling formulations for vaginal application,” Acta Pharmaceutica, vol. 62, no. 1, pp. 59–70, 2012. [24] K. D. Thakker

Applications of Natural Polymeric Materials in Solid Oral Modified-Release Dosage Forms.

PubMed

Li, Liang; Zhang, Xin; Gu, Xiangqin; Mao, Shirui

2015-01-01

Solid oral modified-release dosage forms provide numerous advantages for drug delivery compared to dosage forms where the drugs are released and absorbed rapidly following ingestion. Natural polymers are of particular interest as drug carriers due to their good safety profile, biocompatibility, biodegradability, and rich sources. This review described the current applications of important natural polymers, such as chitosan, alginate, pectin, guar gum, and xanthan gum, in solid oral modified-release dosage forms. It was shown that natural polymers have been widely used to fabricate solid oral modified-release dosage forms such as matrix tablets, pellets and beads, and especially oral drug delivery systems such as gastroretentive and colon drug delivery systems. Moreover, chemical modifications could overcome the shortcomings associated with the use of natural polymers, and the combination of two or more polymers presented further advantages compared with that of single polymer. In conclusion, natural polymers and modified natural polymers have promising applications in solid oral modified-release dosage forms. However, commercial products based on them are still limited. To accelerate the application of natural polymers in commercial products, in vivo behavior of natural polymers-based solid oral modified-release dosage forms should be deeply investigated, and meanwhile quality of the natural polymers should be controlled strictly, and the influence of formulation and process parameters need to be understood intensively.

Moisturizing effect of cosmetic formulations containing Aloe vera extract in different concentrations assessed by skin bioengineering techniques.

PubMed

Dal'Belo, Susi Elaine; Gaspar, Lorena Rigo; Maia Campos, Patrícia Maria Berardo Gonçalves

2006-11-01

The polysaccharide-rich composition of Aloe vera extracts (Aloe barbadensis Miller), often used in cosmetic formulations, may impart moisturizing properties to the product. The aim of this study was to evaluate the effect of cosmetic formulations containing different concentrations of freeze-dried Aloe vera extract on skin hydration, after a single and a 1- and 2-week period of application, by using skin bioengineering techniques. Stable formulations containing 5% (w/w) of a trilaureth-4 phosphate-based blend were supplemented with 0.10%, 0.25% or 0.50% (w/w) of freeze-dried Aloe vera extract and applied to the volar forearm of 20 female subjects. Skin conditions in terms of the water content of the stratum corneum and of transepidermal water loss (TEWL) (Corneometer CM 825 and Tewameter TM 210) were analysed before and after a single and 1- and 2-week period of daily application. After a single application, only formulations supplemented with 0.25% and 0.50% (w/w) of Aloe vera extract increased the water content of the stratum corneum, while after the 2-week period application, all formulations containing the extract (0.10%, 0.25% and 0.50%) had the same effect, in both cases as compared with the vehicle. TEWL was not modified after a single and after 1- and 2-week period of application, when compared with the vehicle. Our results show that freeze-dried Aloe vera extract is a natural effective ingredient for improving skin hydration, possibly through a humectant mechanism. Consequently, it may be used in moisturizing cosmetic formulations and also as a complement in the treatment of dry skin.

Antioxidant capacities and total phenolic contents of 20 polyherbal remedies used as tonics by folk healers in Phatthalung and Songkhla provinces, Thailand.

PubMed

Chanthasri, Wipawee; Puangkeaw, Nuntitporn; Kunworarath, Nongluk; Jaisamut, Patcharawalai; Limsuwan, Surasak; Maneenoon, Katesarin; Choochana, Piyapong; Chusri, Sasitorn

2018-02-21

Uses of polyherbal formulations have played a major role in traditional medicine. The present study is focused on the formulations used in traditional Thai folkloric medicine as tonics or bracers. Twenty documented polyherbal mixtures, used as nourishing tonics by the folk healers in Phatthalung and Songkhla provinces in southern Thailand, are targeted. Despite traditional health claims, there is no scientific evidence to support the utilization of polyherbal formulations. The phenolic and flavonoid contents of the polyherbal formulations and a series of antioxidant tests were applied to measure their capability as preventive or chain-breaking antioxidants. In addition, the cytotoxic activity of effective formulations was assayed in Vero cells. Ninety-eight plant species belonging to 45 families were used to prepare the tested formulation. The preliminary results revealed that water extracts of THP-R016 and THP-R019 contain a high level of total phenolic and flavonoid contents and exhibit remarkable antioxidant activities, as tested by DPPH, ABTS, and FRAP assays. The extract of THP-R019 also showed the strongest metal chelating activities, whereas THP-R016 extract possessed notable superoxide anion and peroxyl radical scavenging abilities. The data provide evidence that the water extracts of folkloric polyherbal formulations, particularly THP-R016, are a potential source of natural antioxidants, which will be valuable in the pharmaceutical and nutraceutical industries. The free radical scavenging of THP-R016 may be due to the contribution of phenolic and flavonoid contents. Useful characteristics for the consumer, such as the phytochemical profiles of active ingredients, cellular based antioxidant properties and beneficial effects in vivo, are under further investigation.

Gelatin-Based Materials in Ocular Tissue Engineering.

PubMed

Rose, James B; Pacelli, Settimio; Haj, Alicia J El; Dua, Harminder S; Hopkinson, Andrew; White, Lisa J; Rose, Felicity R A J

2014-04-17

Gelatin has been used for many years in pharmaceutical formulation, cell culture and tissue engineering on account of its excellent biocompatibility, ease of processing and availability at low cost. Over the last decade gelatin has been extensively evaluated for numerous ocular applications serving as cell-sheet carriers, bio-adhesives and bio-artificial grafts. These different applications naturally have diverse physical, chemical and biological requirements and this has prompted research into the modification of gelatin and its derivatives. The crosslinking of gelatin alone or in combination with natural or synthetic biopolymers has produced a variety of scaffolds that could be suitable for ocular applications. This review focuses on methods to crosslink gelatin-based materials and how the resulting materials have been applied in ocular tissue engineering. Critical discussion of recent innovations in tissue engineering and regenerative medicine will highlight future opportunities for gelatin-based materials in ophthalmology.

Gelatin-Based Materials in Ocular Tissue Engineering

PubMed Central

Rose, James B.; Pacelli, Settimio; El Haj, Alicia J.; Dua, Harminder S.; Hopkinson, Andrew; White, Lisa J.; Rose, Felicity R. A. J.

2014-01-01

Gelatin has been used for many years in pharmaceutical formulation, cell culture and tissue engineering on account of its excellent biocompatibility, ease of processing and availability at low cost. Over the last decade gelatin has been extensively evaluated for numerous ocular applications serving as cell-sheet carriers, bio-adhesives and bio-artificial grafts. These different applications naturally have diverse physical, chemical and biological requirements and this has prompted research into the modification of gelatin and its derivatives. The crosslinking of gelatin alone or in combination with natural or synthetic biopolymers has produced a variety of scaffolds that could be suitable for ocular applications. This review focuses on methods to crosslink gelatin-based materials and how the resulting materials have been applied in ocular tissue engineering. Critical discussion of recent innovations in tissue engineering and regenerative medicine will highlight future opportunities for gelatin-based materials in ophthalmology. PMID:28788609

Food, gastrointestinal pH, and models of oral drug absorption.

PubMed

Abuhelwa, Ahmad Y; Williams, Desmond B; Upton, Richard N; Foster, David J R

2017-03-01

This article reviews the major physiological and physicochemical principles of the effect of food and gastrointestinal (GI) pH on the absorption and bioavailability of oral drugs, and the various absorption models that are used to describe/predict oral drug absorption. The rate and extent of oral drug absorption is determined by a complex interaction between a drug's physicochemical properties, GI physiologic factors, and the nature of the formulation administered. GI pH is an important factor that can markedly affect oral drug absorption and bioavailability as it may have significant influence on drug dissolution & solubility, drug release, drug stability, and intestinal permeability. Different regions of the GI tract have different drug absorptive properties. Thus, the transit time in each GI region and its variability between subjects may contribute to the variability in the rate and/or extent of drug absorption. Food-drug interactions can result in delayed, decreased, increased, and sometimes un-altered drug absorption. Food effects on oral absorption can be achieved by direct and indirect mechanisms. Various models have been proposed to describe oral absorption ranging from empirical models to the more sophisticated "mechanism-based" models. Through understanding of the physicochemical and physiological rate-limiting factors affecting oral absorption, modellers can implement simplified population-based modelling approaches that are less complex than whole-body physiologically-based models but still capture the essential elements in a physiological way and hence will be more suited for population modelling of large clinical data sets. It will also help formulation scientists to better predict formulation performance and to develop formulations that maximize oral bioavailability. Copyright © 2016 Elsevier B.V. All rights reserved.

Efficiency of a new strategy involving a new class of natural hetero-ligand iron(III) chelates (Fe(III)-NHL) to improve fruit tree growth in alkaline/calcareous soils.

PubMed

Fuentes, Marta; Ortuño, María F; Pérez-Sarmiento, Francisco; Bacaicoa, Eva; Baigorri, Roberto; Conejero, Wenceslao; Torrecillas, Arturo; García-Mina, José M

2012-12-01

Iron (Fe) chlorosis is a serious problem affecting the yield and quality of numerous crops and fruit trees cultivated in alkaline/calcareous soils. This paper describes the efficiency of a new class of natural hetero-ligand Fe(III) chelates (Fe-NHL) to provide available Fe for chlorotic lemon trees grown in alkaline/calcareous soils. These chelates involve the participation in the reaction system of a partially humified lignin-based natural polymer and citric acid. First results showed that Fe-NHL was adsorbed on the soil matrix while maintaining available Fe for plants in alkaline/calcareous solution. The effects of using three different sources as Fe fertilisers were also compared: two Fe-NHL formulations (NHL1, containing 100% of Fe as Fe-NHL, and NHL2, containing 80% of Fe as Fe-NHL and 20% of Fe as Fe-ethylenediamine-N,N'-bis-(o-hydroxyphenylacetic) acid (Fe-EDDHA)) and Fe-EDDHA. Both Fe-NHL formulations increased fruit yield without negative effects on fruit quality in comparison with Fe-EDDHA. In the absence of the Fe-starter fraction (NHL1), trees seemed to optimise Fe assimilation and translocation from Fe-NHL, directing it to those parts of the plant more involved in development. The field assays confirmed that Fe-NHL-based fertilisers are able to provide Fe to chlorotic trees, with results comparable to Fe-EDDHA. Besides, this would imply a more sustainable and less expensive remediation than synthetic chelates. Copyright © 2012 Society of Chemical Industry.

Treatment of a multiple sclerosis animal model by a novel nanodrop formulation of a natural antioxidant

PubMed Central

Binyamin, Orli; Larush, Liraz; Frid, Kati; Keller, Guy; Friedman-Levi, Yael; Ovadia, Haim; Abramsky, Oded; Magdassi, Shlomo; Gabizon, Ruth

2015-01-01

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system and is associated with demyelination, neurodegeneration, and sensitivity to oxidative stress. In this work, we administered a nanodroplet formulation of pomegranate seed oil (PSO), denominated Nano-PSO, to mice induced for experimental autoimmune encephalomyelitis (EAE), an established model of MS. PSO comprises high levels of punicic acid, a unique polyunsaturated fatty acid considered as one of the strongest natural antioxidants. We show here that while EAE-induced mice treated with natural PSO presented some reduction in disease burden, this beneficial effect increased significantly when EAE mice were treated with Nano-PSO of specific size nanodroplets at much lower concentrations of the oil. Pathological examinations revealed that Nano-PSO administration dramatically reduced demyelination and oxidation of lipids in the brains of the affected animals, which are hallmarks of this severe neurological disease. We propose that novel formulations of natural antioxidants such as Nano-PSO may be considered for the treatment of patients suffering from demyelinating diseases. On the mechanistic side, our results demonstrate that lipid oxidation may be a seminal feature in both demyelination and neurodegeneration. PMID:26648720

Formulation and in vitro evaluation of sustained release matrix tablets using cross-linked natural gum.

PubMed

Jamil, Qurratul Ain; Masood, Muhammad Irfan; Jamil, Muhammad Nauman; Masood, Imran; Iqbal, Shahid Muhammad

2017-03-01

Polysaccharide gums because of their biocompatibility, biodegradability and non-immunogenic properties are considered as the best choice for preparing sustained release tablets as compared to their synthetic counterpart. The cross linking of natural gums in matrix tablets increase the sustained release property of matrix tablets. Isoniazid is a first line therapy of tuberculosis, belongs to BCS I with half-life of 3-4 hours. These characteristics make isoniazid a good candidate for sustained release dosage form. Karaya gum crossed linked with trisodium tri metaphosphate was used as release rate retardant for preparing isoniazid cross-linked matrix tablet. Total 8 sustained release formulations were prepared. Both granules and tablets were evaluated under in vitro condition against different parameters. Dissolution studies were performed with all eight formulations for 12 hours using USP apparatus I. Four formulations designated as F1, F2, F3, F4 have drug and karaya gum while other four formulations F5, F6, F7, F8 have drug and crossed linked polymer in ratios of 1:1, 1:2, 1:3 and 1:4 respectively. Dissolution data was analyzed by using different kinetic models. Best fit model for most efficient formulation was zero order while release mechanism was super case I. Formulation 8 showed sufficiently slow release kinetics and about 83% of drug was released in 10 hours, indicating that cross-linked karaya gum proved efficient in preparing sustained release tablets.

Gelatin as Biomaterial for Tissue Engineering.

PubMed

Echave, Mari C; Saenz del Burgo, Laura; Pedraz, Jose L; Orive, Gorka

2017-01-01

Tissue engineering is considered one of the most important therapeutic strategies of regenerative medicine. The main objective of these new technologies is the development of substitutes made with biomaterials that are able to heal, repair or regenerate injured or diseased tissues and organs. These constructs seek to unlock the limited ability of human tissues and organs to regenerate. In this review, we highlight the convenient intrinsic properties of gelatin for the design and development of advanced systems for tissue engineering. Gelatin is a natural origin protein derived from collagen hydrolysis. We outline herein a state of the art of gelatin-based composites in order to overcome limitations of this polymeric material and modulate the properties of the formulations. Control release of bioactive molecules, formulations with conductive properties or systems with improved mechanical properties can be obtained using gelatin composites. Many studies have found that the use of calcium phosphate ceramics and diverse synthetic polymers in combination with gelatin improve the mechanical properties of the structures. On the other hand, polyaniline and carbon-based nanosubstrates are interesting molecules to provide gelatin-based systems with conductive properties, especially for cardiac and nerve tissue engineering. Finally, this review provides an overview of the different types of gelatin-based structures including nanoparticles, microparticles, 3D scaffolds, electrospun nanofibers and in situ gelling formulations. Thanks to the significant progress that has already been made, along with others that will be achieved in a near future, the safe and effective clinical implementation of gelatin-based products is expected to accelerate and expand shortly. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Assessments of a Turbulence Model Based on Menter's Modification to Rotta's Two-Equation Model

NASA Technical Reports Server (NTRS)

Abdol-Hamid, Khaled S.

2013-01-01

The main objective of this paper is to construct a turbulence model with a more reliable second equation simulating length scale. In the present paper, we assess the length scale equation based on Menter s modification to Rotta s two-equation model. Rotta shows that a reliable second equation can be formed in an exact transport equation from the turbulent length scale L and kinetic energy. Rotta s equation is well suited for a term-by-term modeling and shows some interesting features compared to other approaches. The most important difference is that the formulation leads to a natural inclusion of higher order velocity derivatives into the source terms of the scale equation, which has the potential to enhance the capability of Reynolds-averaged Navier-Stokes (RANS) to simulate unsteady flows. The model is implemented in the PAB3D solver with complete formulation, usage methodology, and validation examples to demonstrate its capabilities. The detailed studies include grid convergence. Near-wall and shear flows cases are documented and compared with experimental and Large Eddy Simulation (LES) data. The results from this formulation are as good or better than the well-known SST turbulence model and much better than k-epsilon results. Overall, the study provides useful insights into the model capability in predicting attached and separated flows.

The influence of selected excipients on the rheological behaviour of chitosan based ocular pharmaceutical systems

NASA Astrophysics Data System (ADS)

Budai, L.; Szabadi, E.; Hajdú, M.; Budai, M.; Klebovich, I.; Antal, I.

2015-04-01

Aims: Chitosan, a modified natural carbohydrate polymer, has received great attention in diverse scientific fields including pharmaceutical and biomedical research areas. Besides its low toxicity, mucoadhesiveness and biodegradability its special favourable rheological feature makes it a unique gelling agent for the design of ocular systems. Chitosan based (2.0 w/v %) ocular systems containing selected excipients were formulated in order to investigate the rheological influence of applied auxiliary materials. Rotational and oscillatory rheological properties of propylene glycol (1.0-20.0 w/v %), glycerin (1.0-5.0 w/v %) and castor oil (1.0-5.0 w/v %) containing chitosan gels were evaluated. The rheological behaviour of formulated ocular gels were compared before and after steam sterilization. Methods: Rotational and oscillatory rheological measurements were carried out with Kinexus Pro Rheometer. Comparison of flow curves and oscillatory frequency sweep measurements in the linear viscoelastic region made possible the evaluation of rheological effect of selected excipients. Results: In the applied concentration range the effect of propylene glycol among the selected excipients presents the most significant impact on rheology of chitosan formulations. Steam sterilization results in reduced viscosity in most of chitosan gels. However, the presence of polyols appears to prevent the degradation of chitosan after steam sterilization.

An Alternative Lattice Field Theory Formulation Inspired by Lattice Supersymmetry-Summary of the Formulation-

NASA Astrophysics Data System (ADS)

D'Adda, Alessandro; Kawamoto, Noboru; Saito, Jun

2018-03-01

We propose a lattice field theory formulation which overcomes some fundamental diffculties in realizing exact supersymmetry on the lattice. The Leibniz rule for the difference operator can be recovered by defining a new product on the lattice, the star product, and the chiral fermion species doublers degrees of freedom can be avoided consistently. This framework is general enough to formulate non-supersymmetric lattice field theory without chiral fermion problem. This lattice formulation has a nonlocal nature and is essentially equivalent to the corresponding continuum theory. We can show that the locality of the star product is recovered exponentially in the continuum limit. Possible regularization procedures are proposed.The associativity of the product and the lattice translational invariance of the formulation will be discussed.

Development of a direct three-dimensional biomicrofabrication concept based on electrospraying a custom made siloxane sol.

PubMed

Sullivan, Alice C; Jayasinghe, Suwan N

2007-07-19

We demonstrate here the discovery of a unique and direct three-dimensional biomicrofabrication concept possessing the ability to revolutionize the jet-based fabrication arena. Previous work carried out on similar jet-based approaches have been successful in fabricating only vertical wallpillar-structures by the controlled deposition of stacked droplets. However, these advanced jet-techniques have not been able to directly fabricate self-supporting archeslinks (without molds or reaction methods) between adjacent structures (walls or pillars). Our work reported here gives birth to a unique type of jet determined by high intensity electric fields, which is derived from a specially formulated siloxane sol. The sol studied here has been chosen for its attractive properties (such as an excellent cross-linking nature as well as the ability to polymerize via polycondensation on deposition to its biocompatability), which promotes direct forming of biostructures with nanometer (<50 nm) sized droplets in three dimensions. We foresee that this direct three-dimensional biomicrofabrication jet technique coupled with a variety of formulated sols having focused and enhanced functionality will be explored throughout the physical and life sciences.

The effect of Pro NanoLipospheres (PNL) formulation containing natural absorption enhancers on the oral bioavailability of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) in a rat model.

PubMed

Cherniakov, Irina; Izgelov, Dvora; Domb, Abraham J; Hoffman, Amnon

2017-11-15

The lipophilic phytocannabinoids cannabidiol (CBD) and Δ 9 -tetrahydrocannabinol (THC) show therapeutic efficacy in various medical conditions. Both molecules are poorly water soluble and subjected to extensive first pass metabolism in the gastrointestinal tract, leading to a limited oral bioavailability of approximately 9%. We have developed an advanced lipid based Self-Emulsifying Drug Delivery System termed Advanced Pro-NanoLiposphere (PNL) pre-concentrate. The PNL is composed of lipid and emulsifying excipients of GRAS status and are known to increase solubility and reduce Phase I metabolism of lipophilic active compounds. Advanced PNLs are PNLs with an incorporated natural absorption enhancers. These molecules are natural alkaloids and phenolic compounds which were reported to inhibit certain phase I and phase II metabolism processes. Here we use piperine, curcumin and resveratrol to formulate the Advanced-PNL formulations. Consequently, we have explored the utility of these Advanced-PNLs on CBD and THC oral bioavailability. Oral administration of CBD-piperine-PNL resulted in 6-fold increase in AUC compared to CBD solution, proving to be the most effective of the screened formulations. The same trend was found in pharmacokinetic experiments of THC-piperine-PNL which resulted in a 9.3-fold increase in AUC as compared to THC solution. Our Piperine-PNL can be used as a platform for synchronized delivery of piperine and CBD or THC to the enterocyte site. This co-localization provides an increase in CBD and THC bioavailability by its effect at the pre-enterocyte and the enterocyte levels of the absorption process. The extra augmentation in the absorption of CBD and THC by incorporating piperine into PNL is attributed to the inhibition of Phase I and phase II metabolism by piperine in addition to the Phase I metabolism and P-gp inhibition by PNL. These novel results pave the way to utilize piperine-PNL delivery system for other poorly soluble, highly metabolized compounds that currently cannot be administered orally. Copyright © 2017. Published by Elsevier B.V.

Effect of formulation and process variables on lipid based sustained release tablets via continuous twin screw granulation: A comparative study.

PubMed

Kallakunta, Venkata Raman; Tiwari, Roshan; Sarabu, Sandeep; Bandari, Suresh; Repka, Michael A

2018-05-14

The current study's aim is to prepare lipid based sustained release tablets via a twin-screw granulation technique and compare those dosage forms with conventional techniques, namely wet granulation and direct compression. The granules were successfully manufactured in a single-step, continuous twin-screw granulation process with a low proportion of binder (Klucel™ EF, HPC SSL) using Compritol® 888 ATO, Precirol® ATO 5 and Geleol™ as sustained release agents. The granules prepared showed good flow characteristics and compaction properties. DSC and XRD studies were conducted to characterize the granules prepared via a twin-screw granulation method and the results demonstrated the crystalline nature of lipids within the granules. FTIR data indicated that there were no interactions with the formulation components investigated. The formulations developed by all three methods were compressed into tablets with a mechanical strength of 14-16 KP. The tablets formulated were characterized for physicochemical properties, in vitro drug release studies, water uptake and erosion studies. These results showed that the drug was not completely released after 24 h for tablets developed by the wet granulation process using all three lipids. The tablets prepared by the direct compression method demonstrated a burst release within 8 to 10 h from Precirol ATO 5® and Geleol™ formulations compared to Compritol® 888 ATO. However, tablets prepared using twin-screw granulation exhibited sustained release of the drug over 24 h and the water uptake and erosion results were in accordance with dissolution data. Stability data for 45 days at accelerated conditions (40 °C/75% RH) showed similar release profiles with ƒ2 values above 50 for all of the twin screw granulation formulations, indicating the suitability of the process for formulating sustained release tablets. These findings of a single-step, continuous twin-screw granulation process are novel and demonstrate new opportunities for development of sustained release tablets. Copyright © 2017. Published by Elsevier B.V.

Potential of insulin nanoparticle formulations for oral delivery and diabetes treatment.

PubMed

Wong, Chun Y; Al-Salami, Hani; Dass, Crispin R

2017-10-28

Nanoparticles have demonstrated significant advancements in potential oral delivery of insulin. In this publication, we review the current status of polymeric, inorganic and solid-lipid nanoparticles designed for oral administration of insulin. Firstly, the structure and physiological function of insulin are examined. Then, the efficiency and shortcomings of insulin nanoparticle are discussed. These include the susceptibility to digestive enzyme degradation, instability in the acidic pH environment, poor mucus diffusion and inadequate permeation through the gastrointestinal epithelium. In order to optimise the nanocarriers, the following considerations, including polymer nature, surface charge, size, polydispersity index and morphology of nanoparticles, have to be taken into account. Some novel designs such as chitosan-based glucose-responsive nanoparticles, layer by layer technique-based nanoparticles and zwitterion nanoparticles are being adopted to overcome the physiological challenges. The review ends with some future directions and challenges to be addressed for the success of oral delivery of insulin-loaded nanoparticle formulation. Copyright © 2017 Elsevier B.V. All rights reserved.

Applications of Alginate-Based Bioinks in 3D Bioprinting.

PubMed

Axpe, Eneko; Oyen, Michelle L

2016-11-25

Three-dimensional (3D) bioprinting is on the cusp of permitting the direct fabrication of artificial living tissue. Multicellular building blocks (bioinks) are dispensed layer by layer and scaled for the target construct. However, only a few materials are able to fulfill the considerable requirements for suitable bioink formulation, a critical component of efficient 3D bioprinting. Alginate, a naturally occurring polysaccharide, is clearly the most commonly employed material in current bioinks. Here, we discuss the benefits and disadvantages of the use of alginate in 3D bioprinting by summarizing the most recent studies that used alginate for printing vascular tissue, bone and cartilage. In addition, other breakthroughs in the use of alginate in bioprinting are discussed, including strategies to improve its structural and degradation characteristics. In this review, we organize the available literature in order to inspire and accelerate novel alginate-based bioink formulations with enhanced properties for future applications in basic research, drug screening and regenerative medicine.

Preparation and in vitro evaluation of xanthan gum facilitated superabsorbent polymeric microspheres.

PubMed

Bhattacharya, Shiv Sankar; Mazahir, Farhan; Banerjee, Subham; Verma, Anurag; Ghosh, Amitava

2013-10-15

Interpenetrating polymer network (IPN) hydrogel microspheres of xanthan gum (XG) based superabsorbent polymer (SAP) and poly(vinyl alcohol) (PVA) were prepared by water-in-oil (w/o) emulsion crosslinking method for sustained release of ciprofloxacin hydrochloride (CIPRO). The microspheres were prepared with various ratios of hydrolyzed SAP to PVA and extent of crosslinking density. The prepared microspheres with loose and rigid surfaces were evidenced by scanning electron microscope (SEM). Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis confirmed the IPN formation. Differential scanning calorimetry (DSC) study was performed to understand the dispersion nature of drug after encapsulation. The in vitro drug release study was extensively evaluated depending on the process variables in both acidic and alkaline media. All the formulations exhibited satisfactory physicochemical and in vitro release characteristics. Release data indicated a non-Fickian trend of drug release from the formulations. Based on the results, this study suggest that CIPRO loaded IPN microspheres were suitable for sustained release application. Copyright © 2013 Elsevier Ltd. All rights reserved.

Applications of Alginate-Based Bioinks in 3D Bioprinting

PubMed Central

Axpe, Eneko; Oyen, Michelle L.

2016-01-01

Three-dimensional (3D) bioprinting is on the cusp of permitting the direct fabrication of artificial living tissue. Multicellular building blocks (bioinks) are dispensed layer by layer and scaled for the target construct. However, only a few materials are able to fulfill the considerable requirements for suitable bioink formulation, a critical component of efficient 3D bioprinting. Alginate, a naturally occurring polysaccharide, is clearly the most commonly employed material in current bioinks. Here, we discuss the benefits and disadvantages of the use of alginate in 3D bioprinting by summarizing the most recent studies that used alginate for printing vascular tissue, bone and cartilage. In addition, other breakthroughs in the use of alginate in bioprinting are discussed, including strategies to improve its structural and degradation characteristics. In this review, we organize the available literature in order to inspire and accelerate novel alginate-based bioink formulations with enhanced properties for future applications in basic research, drug screening and regenerative medicine. PMID:27898010

Benzyl Benzoate-Loaded Microemulsion for Topical Applications: Enhanced Dermatokinetic Profile and Better Delivery Promises.

PubMed

Sharma, Gajanand; Dhankar, Geeta; Thakur, Kanika; Raza, Kaisar; Katare, O P

2016-10-01

Benzyl benzoate (BB) is one of the oldest drugs used for the treatment of scabies and is recommended as the "first-line intervention" for the cost-effective treatment of the disease. Though a promising candidate, its application is reported to be associated with irritation of the skin and eye, resulting in poor patient compliance. Hence, the present study aims to develop BB-loaded topical microemulsion for the safer and effective delivery of BB. Pseudo-ternary phase diagrams with BB as the oily phase itself, along with Tween 80 as surfactant, and mixture of phospholipid and ethanol as the co-surfactant along with aqueous solution as the external phase were constructed and various compositions were formulated. The optimized formulation was characterized for particle-size, zeta-potential, drug-content, globule-morphology pH, and refractive-index, whereas evaluated for skin permeation, retention, compliance, and dermatokinetics. The nanosized formulation offered threefold higher drug permeation vis-a-vis plain drug solution across LACA mice abdominal skin. The drug retention of the selected formulation was nearly twice of that from the marketed product, assuring depot formulation and sustained release. The skin histopathology revealed the non-irritant nature of the formulation, as no changes in the normal skin histology were observed. The dermatokinetic studies confirmed better permeation and enhanced skin bioavailability of BB to epidermis as well as dermis vis-à-vis the conventional product. The results indicate that the developed lipid-based microemulsion hydrogel can alleviate the concerns associated with BB and can provide a better and safer delivery option in substantial amounts to various skin layers.

Formulation and acoustic studies of a new phase-shift agent for diagnostic and therapeutic ultrasound.

PubMed

Sheeran, Paul S; Luois, Samantha; Dayton, Paul A; Matsunaga, Terry O

2011-09-06

Recent efforts in the area of acoustic droplet vaporization with the objective of designing extravascular ultrasound contrast agents has led to the development of stabilized, lipid-encapsulated nanodroplets of the highly volatile compound decafluorobutane (DFB). We developed two methods of generating DFB droplets, the first of which involves condensing DFB gas (boiling point from -1.1 to -2 °C) followed by extrusion with a lipid formulation in HEPES buffer. Acoustic droplet vaporization of micrometer-sized lipid-coated droplets at diagnostic ultrasound frequencies and mechanical indices were confirmed optically. In our second formulation methodology, we demonstrate the formulation of submicrometer-sized lipid-coated nanodroplets based upon condensation of preformed microbubbles containing DFB. The droplets are routinely in the 200-300 nm range and yield microbubbles on the order of 1-5 μm once vaporized, consistent with ideal gas law expansion predictions. The simple and effective nature of this methodology allows for the development of a variety of different formulations that can be used for imaging, drug and gene delivery, and therapy. This study is the first to our knowledge to demonstrate both a method of generating ADV agents by microbubble condensation and formulation of primarily submicrometer droplets of decafluorobutane that remain stable at physiological temperatures. Finally, activation of DFB nanodroplets is demonstrated using pressures within the FDA guidelines for diagnostic imaging, which may minimize the potential for bioeffects in humans. This methodology offers a new means of developing extravascular contrast agents for diagnostic and therapeutic applications. © 2011 American Chemical Society

A comparative study on stress and compliance based structural topology optimization

NASA Astrophysics Data System (ADS)

Hailu Shimels, G.; Dereje Engida, W.; Fakhruldin Mohd, H.

2017-10-01

Most of structural topology optimization problems have been formulated and solved to either minimize compliance or weight of a structure under volume or stress constraints, respectively. Even if, a lot of researches are conducted on these two formulation techniques separately, there is no clear comparative study between the two approaches. This paper intends to compare these formulation techniques, so that an end user or designer can choose the best one based on the problems they have. Benchmark problems under the same boundary and loading conditions are defined, solved and results are compared based on these formulations. Simulation results shows that the two formulation techniques are dependent on the type of loading and boundary conditions defined. Maximum stress induced in the design domain is higher when the design domains are formulated using compliance based formulations. Optimal layouts from compliance minimization formulation has complex layout than stress based ones which may lead the manufacturing of the optimal layouts to be challenging. Optimal layouts from compliance based formulations are dependent on the material to be distributed. On the other hand, optimal layouts from stress based formulation are dependent on the type of material used to define the design domain. High computational time for stress based topology optimization is still a challenge because of the definition of stress constraints at element level. Results also shows that adjustment of convergence criterions can be an alternative solution to minimize the maximum stress developed in optimal layouts. Therefore, a designer or end user should choose a method of formulation based on the design domain defined and boundary conditions considered.

Liquefied natural gas tender crashworthiness research

DOT National Transportation Integrated Search

2015-03-23

Research is being conducted to develop technical : information needed to formulate effective natural gas fuel : tender crashworthiness standards. This research is being : performed for the Federal Railroad Administrations (FRAs) : Office of Res...

An Adaptively-Refined, Cartesian, Cell-Based Scheme for the Euler and Navier-Stokes Equations. Ph.D. Thesis - Michigan Univ.

NASA Technical Reports Server (NTRS)

Coirier, William John

1994-01-01

A Cartesian, cell-based scheme for solving the Euler and Navier-Stokes equations in two dimensions is developed and tested. Grids about geometrically complicated bodies are generated automatically, by recursive subdivision of a single Cartesian cell encompassing the entire flow domain. Where the resulting cells intersect bodies, polygonal 'cut' cells are created. The geometry of the cut cells is computed using polygon-clipping algorithms. The grid is stored in a binary-tree data structure which provides a natural means of obtaining cell-to-cell connectivity and of carrying out solution-adaptive refinement. The Euler and Navier-Stokes equations are solved on the resulting grids using a finite-volume formulation. The convective terms are upwinded, with a limited linear reconstruction of the primitive variables used to provide input states to an approximate Riemann solver for computing the fluxes between neighboring cells. A multi-stage time-stepping scheme is used to reach a steady-state solution. Validation of the Euler solver with benchmark numerical and exact solutions is presented. An assessment of the accuracy of the approach is made by uniform and adaptive grid refinements for a steady, transonic, exact solution to the Euler equations. The error of the approach is directly compared to a structured solver formulation. A non smooth flow is also assessed for grid convergence, comparing uniform and adaptively refined results. Several formulations of the viscous terms are assessed analytically, both for accuracy and positivity. The two best formulations are used to compute adaptively refined solutions of the Navier-Stokes equations. These solutions are compared to each other, to experimental results and/or theory for a series of low and moderate Reynolds numbers flow fields. The most suitable viscous discretization is demonstrated for geometrically-complicated internal flows. For flows at high Reynolds numbers, both an altered grid-generation procedure and a different formulation of the viscous terms are shown to be necessary. A hybrid Cartesian/body-fitted grid generation approach is demonstrated. In addition, a grid-generation procedure based on body-aligned cell cutting coupled with a viscous stensil-construction procedure based on quadratic programming is presented.

Allocation and management issues in multiple-transaction open access transmission networks

NASA Astrophysics Data System (ADS)

Tao, Shu

This thesis focuses on some key issues related to allocation and management by the independent grid operator (IGO) of unbundled services in multiple-transaction open access transmission networks. The three unbundled services addressed in the thesis are transmission real power losses, reactive power support requirements from generation sources, and transmission congestion management. We develop the general framework that explicitly represents multiple transactions undertaken simultaneously in the transmission grid. This framework serves as the basis for formulating various problems treated in the thesis. We use this comprehensive framework to develop a physical-flow-based mechanism to allocate the total transmission losses to each transaction using the system. An important property of the allocation scheme is its capability to effectively deal with counter flows that result in the presence of specific transactions. Using the loss allocation results as the basis, we construct the equivalent loss compensation concept and apply it to develop flexible and effective procedures for compensating losses in multiple-transaction networks. We present a new physical-flow-based mechanism for allocating the reactive power support requirements provided by generators in multiple-transaction networks. The allocatable reactive support requirements are formulated as the sum of two specific components---the voltage magnitude variation component and the voltage angle variation component. The formulation utilizes the multiple-transaction framework and makes use of certain simplifying approximations. The formulation leads to a natural allocation as a function of the amount of each transaction. The physical interpretation of each allocation as a sensitivity of the reactive output of a generator is discussed. We propose a congestion management allocation scheme for multiple-transaction networks. The proposed scheme determines the allocation of congestion among the transactions on a physical-flow basis. It also proposes a congestion relief scheme that removes the congestion attributed to each transaction on the network in a least-cost manner to the IGO and determines the appropriate transmission charges to each transaction for its transmission usage. The thesis provides a compendium of problems that are natural extensions of the research results reported here and appear to be good candidates for future work.

Developing Formal Correctness Properties from Natural Language Requirements

NASA Technical Reports Server (NTRS)

Nikora, Allen P.

2006-01-01

This viewgraph presentation reviews the rationale of the program to transform natural language specifications into formal notation.Specifically, automate generation of Linear Temporal Logic (LTL)correctness properties from natural language temporal specifications. There are several reasons for this approach (1) Model-based techniques becoming more widely accepted, (2) Analytical verification techniques (e.g., model checking, theorem proving) significantly more effective at detecting types of specification design errors (e.g., race conditions, deadlock) than manual inspection, (3) Many requirements still written in natural language, which results in a high learning curve for specification languages, associated tools and increased schedule and budget pressure on projects reduce training opportunities for engineers, and (4) Formulation of correctness properties for system models can be a difficult problem. This has relevance to NASA in that it would simplify development of formal correctness properties, lead to more widespread use of model-based specification, design techniques, assist in earlier identification of defects and reduce residual defect content for space mission software systems. The presentation also discusses: potential applications, accomplishments and/or technological transfer potential and the next steps.

Phase I/II Clinical Trial of Hyaluronan-Cisplatin Nanoconjugate for the Treatment of Spontaneous Canine Cancers

PubMed Central

Cai, Shuang; Zhang, Ti; Forrest, W.C.; Yang, Qiuhong; Groer, Chad; Mohr, Eva; Aires, Daniel J.; Axiak-Bechtel, Sandra M.; Flesner, Brian K.; Henry, Carolyn J.; Selting, Kimberly A.; Tate, Deborah; Swarz, Jeffrey A.; Bryan, Jeffrey N.; Forrest, M. Laird

2015-01-01

Objective To conduct an open label, multi-dose Phase I/II clinical study in spontaneous canine cancers and evaluate the pharmacokinetics, safety, and efficacy of the hyaluronan-based cisplatin formulation (HA-Pt). Animals 13 dogs with heterogeneous, naturally occurring cancers. Procedures The dogs received up to four injections of 10-30 mg/m2 HA-Pt into the tumor or peritumoral sub-mucosa at three-week intervals. Blood sample (2 mL) was collected from the jugular catheter at 0.5, 1, 2, 4, and 24 hours following drug administration. A complete blood count and renal profile with urinalysis were conducted prior to and one week after each treatment. Tumor measurements were collected three weeks following each administration to assess response. Results Of the 13 dogs with heterogeneous, naturally occurring cancers, 23% had complete response and 15% had partial response or stable disease. Among the dogs that received drug with low diaquated content, the complete response rate for SCC was 3/7 (43%). Myelosuppression and cardiac toxicity were observed for 38% and 19% of the dogs, respectively. The formulation did not cause nephrotoxicity, the dose-limiting toxicity of standard cisplatin, in any dogs. Conclusions and Clinical Relevance The HA-Pt formulation demonstrated positive response in spontaneous canine squamous cell carcinomas. It did not cause nephrotoxicity in any patients. Canine oral SCC is very homogenous in progression and drug response to human HNSCC, and these results could be useful in developing human treatments. PMID:27580113

Evaluation of Biobased Hydraulic Fluids in Military Construction Equipment

DTIC Science & Technology

2007-10-31

systems. They are basically divided into two groups. One is natural rubber and the other one is a synthetic elastomer. Their formulations and physical...compatibility test. This reference elastomer was specially formulated with Nitrile or Buna N ( NBR -L) material and is widely used in the many

Performance of Arma chinensis reared on an artificial diet formulated using transcriptomic methods

USDA-ARS?s Scientific Manuscript database

An artificial diet formulated for continuous rearing of the predator Arma chinensis was inferior to natural prey when evaluated using life history parameters. A transcriptome analysis identified differentially expressed genes in diet-fed and prey-fed A. chinensis that were suggestive of molecular me...

The rationale for advancing the formulation of azelaic acid vehicles.

PubMed

Draelos, Zoe Diana

2006-02-01

When first approved in December 2002, 15% azelaic acid (AzA) gel represented a significant advance over the available 20% AzA cream. Although a smaller amount of AzA was present in the new formulation, the gel medium provided a highly effective system for delivering the active ingredient, thus providing more effective treatment. This article explores the nature of these 2 vehicles and highlights the importance of the formulation in which dermatologic drugs are delivered.

The use of D-optimal mixture design in optimising okara soap formulation for stratum corneum application.

PubMed

Borhan, Farrah Payyadhah; Abd Gani, Siti Salwa; Shamsuddin, Rosnah

2014-01-01

Okara, soybean waste from tofu and soymilk production, was utilised as a natural antioxidant in soap formulation for stratum corneum application. D-optimal mixture design was employed to investigate the influence of the main compositions of okara soap containing different fatty acid and oils (virgin coconut oil A (24-28% w/w), olive oil B (15-20% w/w), palm oil C (6-10% w/w), castor oil D (15-20% w/w), cocoa butter E (6-10% w/w), and okara F (2-7% w/w)) by saponification process on the response hardness of the soap. The experimental data were utilized to carry out analysis of variance (ANOVA) and to develop a polynomial regression model for okara soap hardness in terms of the six design factors considered in this study. Results revealed that the best mixture was the formulation that included 26.537% A, 19.999% B, 9.998% C, 16.241% D, 7.633% E, and 7.000% F. The results proved that the difference in the level of fatty acid and oils in the formulation significantly affects the hardness of soap. Depending on the desirable level of those six variables, creation of okara based soap with desirable properties better than those of commercial ones is possible.

Determination of elastic constants of a generally orthotropic plate by modal analysis

NASA Astrophysics Data System (ADS)

Lai, T. C.; Lau, T. C.

1993-01-01

This paper describes a method of finding the elastic constants of a generally orthotropic composite thin plate through modal analysis based on a Rayleigh-Ritz formulation. The natural frequencies and mode shapes for a plate with free-free boundary conditions are obtained with chirp excitation. Based on the eigenvalue equation and the constitutive equations of the plate, an iteration scheme is derived using the experimentally determined natural frequencies to arrive at a set of converged values for the elastic constants. Four sets of experimental data are required for the four independent constants: namely the two Young's moduli E1 and E2, the in-plane shear modulus G12, and one Poisson's ratio nu12. The other Poisson's ratio nu21 can then be determined from the relationship among the constants. Comparison with static test results indicate good agreement. Choosing the right combinations of natural modes together with a set of reasonable initial estimates for the constants to start the iteration has been found to be crucial in achieving convergence.

The influence of supplemented Curcuma in feed formulation to improve growth rate and feed efficiency of catfish (Clarias sp.)

NASA Astrophysics Data System (ADS)

Ulum, M. M.; Zubaidah, M.; Arief, M.; Prayogo

2018-04-01

Catfish (Clarias sp.) is very potential to be developed as a food fish. The use of the feed additive in feed intended to improve the health, productivity and compliance with animal nutrition. Feed additive is to use ginger are derived from nature.The purpose of this study was to determine the potential increase in feed formulation. The Curcuma effect on growth rate and feed efficiency of catfish (Clarias sp.). The method used experimental methods and design complete random with 4 treatments and 5 replications. The parameters examined in this study aregrowth rate and efficiency feed.The research showed that the ANOVA markedly dissimilar ( P< 0.05 ) against growth rate and efficiency feed catfishes. The average is 0.275 - 0.33 growth and the results efficiency feed catfishes of 60.70 % - 73.10 % and the results obtained temperature water quality around 27-30°C, pH 7-8, and DO 3.09-6.4. Based on this research cultivator of the suggested use flour curcuma as feed additive on formulations feed.

Full Wave Parallel Code for Modeling RF Fields in Hot Plasmas

NASA Astrophysics Data System (ADS)

Spencer, Joseph; Svidzinski, Vladimir; Evstatiev, Evstati; Galkin, Sergei; Kim, Jin-Soo

2015-11-01

FAR-TECH, Inc. is developing a suite of full wave RF codes in hot plasmas. It is based on a formulation in configuration space with grid adaptation capability. The conductivity kernel (which includes a nonlocal dielectric response) is calculated by integrating the linearized Vlasov equation along unperturbed test particle orbits. For Tokamak applications a 2-D version of the code is being developed. Progress of this work will be reported. This suite of codes has the following advantages over existing spectral codes: 1) It utilizes the localized nature of plasma dielectric response to the RF field and calculates this response numerically without approximations. 2) It uses an adaptive grid to better resolve resonances in plasma and antenna structures. 3) It uses an efficient sparse matrix solver to solve the formulated linear equations. The linear wave equation is formulated using two approaches: for cold plasmas the local cold plasma dielectric tensor is used (resolving resonances by particle collisions), while for hot plasmas the conductivity kernel is calculated. Work is supported by the U.S. DOE SBIR program.

Fokker Planck Rosenbluth-type equations for self-gravitating systems in the 1PN approximation

NASA Astrophysics Data System (ADS)

Ramos-Caro, Javier; González, Guillermo A.

2008-02-01

We present two formulations of Fokker Planck Rosenbluth-type (FPR) equations for many-particle self-gravitating systems, with first-order relativistic corrections in the post-Newtonian approach (1PN). The first starts from a covariant Fokker Planck equation for a simple gas, introduced recently by Chacón-Acosta and Kremer (2007 Phys. Rev. E 76 021201). The second derivation is based on the establishment of an 1PN-BBGKY hierarchy, developed systematically from the 1PN microscopic law of force and using the Klimontovich Dupree (KD) method. We close the hierarchy by the introduction of a two-point correlation function that describes adequately the relaxation process. This picture reveals an aspect that is not considered in the first formulation: the contribution of ternary correlation patterns to the diffusion coefficients, as a consequence of the nature of 1PN interaction. Both formulations can be considered as a generalization of the equation derived by Rezania and Sobouti (2000 Astron. Astrophys. 354 1110), to stellar systems where the relativistic effects of gravitation play a significant role.

Literature Search for New Physical Methods of Biological Aerosol Detection

DTIC Science & Technology

1985-04-01

alkaline medium were first tried) to give absorption maxima close to the wavelength of the laser. Pesticides in natural water were also derivatized and...10, p313-318: Identification of Infrared Spectra by Correlation- Based File Searching. 146 19 8 Ferraro J.R. and Basile L.J., Editors; Fourier...D.G. and Vldrine D.W., Analy. Chem., v.54, p546-548: Photoacoustic TR Spectra in the Investigation of Bonding Effects in Formulated Pesticides . [Used

The "Bermuda triangle" of neonatal neurology: cerebral palsy, neonatal encephalopathy, and intrapartum asphyxia.

PubMed

Shevell, Michael I

2004-03-01

The terms "cerebral palsy," "neonatal encephalopathy," and "intrapartum asphyxia" are frequently used in pediatric neurology. This article presents concise, verifiable definitions for each of these entities based on our current understanding and formulates the nature of the interrelationships between them. The aim is to provide a level of clarity that will enhance diagnostic and pathogenetic precision and minimize conceptual misunderstanding. This should aid future therapeutic and research efforts in this important area.

The bliss (not the problem) of motor abundance (not redundancy).

PubMed

Latash, Mark L

2012-03-01

Motor control is an area of natural science exploring how the nervous system interacts with other body parts and the environment to produce purposeful, coordinated actions. A central problem of motor control-the problem of motor redundancy-was formulated by Nikolai Bernstein as the problem of elimination of redundant degrees-of-freedom. Traditionally, this problem has been addressed using optimization methods based on a variety of cost functions. This review draws attention to a body of recent findings suggesting that the problem has been formulated incorrectly. An alternative view has been suggested as the principle of abundance, which considers the apparently redundant degrees-of-freedom as useful and even vital for many aspects of motor behavior. Over the past 10 years, dozens of publications have provided support for this view based on the ideas of synergic control, computational apparatus of the uncontrolled manifold hypothesis, and the equilibrium-point (referent configuration) hypothesis. In particular, large amounts of "good variance"-variance in the space of elements that has no effect on the overall performance-have been documented across a variety of natural actions. "Good variance" helps an abundant system to deal with secondary tasks and unexpected perturbations; its amount shows adaptive modulation across a variety of conditions. These data support the view that there is no problem of motor redundancy; there is bliss of motor abundance.

Iron-montmorillonite clays as active sorbents for the decontamination of hazardous chemical warfare agents.

PubMed

Carniato, F; Bisio, C; Evangelisti, C; Psaro, R; Dal Santo, V; Costenaro, D; Marchese, L; Guidotti, M

2018-02-27

A class of heterogeneous catalysts based on commercial bentonite from natural origin, containing at least 80 wt% of montmorillonite clay, was designed to transform selectively and under mild conditions toxic organosulfur and organophosphorus chemical warfare agents into non-noxious products with a reduced impact on health and environment. The bentonite from the natural origin was modified by introducing iron species and acid sites in the interlayer space, aiming to obtain a sorbent with strong catalytic oxidising and hydrolytic properties. The catalytic performance of these materials was evaluated in the oxidative abatement of (2-chloroethyl)ethyl sulfide (CEES), a simulant of sulfur mustard, in the presence of aqueous hydrogen peroxide as an oxidant. A new decontamination formulation was, moreover, proposed and obtained by mixing sodium perborate, as a solid oxidant, to iron-bentonite catalysts. Solid-phase decontamination tests, performed on a cotton textile support contaminated with organosulfide and organophosphonate simulant agents revealed the good activity of the solid formulation, especially in the in situ detoxification of blistering agents. Tests carried out on the real blistering warfare agent, sulfur mustard (HD agent), showed that, thanks to the co-presence of the iron-based clay together with the solid oxidant component, a good decontamination of the test surface from the real warfare agent could be achieved (80% contaminant degradation, under ambient conditions, in 24 h).

Stability and natural vibration analysis of laminated plates by using a mixed element based on a refined plate theory

NASA Technical Reports Server (NTRS)

Putcha, N. S.; Reddy, J. N.

1986-01-01

A mixed shear flexible finite element, with relaxed continuity, is developed for the geometrically linear and nonlinear analysis of layered anisotropic plates. The element formulation is based on a refined higher order theory which satisfies the zero transverse shear stress boundary conditions on the top and bottom faces of the plate and requires no shear correction coefficients. The mixed finite element developed herein consists of eleven degrees of freedom per node which include three displacements, two rotations and six moment resultants. The element is evaluated for its accuracy in the analysis of the stability and vibration of anisotropic rectangular plates with different lamination schemes and boundary conditions. The mixed finite element described here for the higher order theory gives very accurate results for buckling loads and natural frequencies.

Quadratic partial eigenvalue assignment in large-scale stochastic dynamic systems for resilient and economic design

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

Das, Sonjoy; Goswami, Kundan; Datta, Biswa N.

2014-12-10

Failure of structural systems under dynamic loading can be prevented via active vibration control which shifts the damped natural frequencies of the systems away from the dominant range of loading spectrum. The damped natural frequencies and the dynamic load typically show significant variations in practice. A computationally efficient methodology based on quadratic partial eigenvalue assignment technique and optimization under uncertainty has been formulated in the present work that will rigorously account for these variations and result in an economic and resilient design of structures. A novel scheme based on hierarchical clustering and importance sampling is also developed in this workmore » for accurate and efficient estimation of probability of failure to guarantee the desired resilience level of the designed system. Numerical examples are presented to illustrate the proposed methodology.« less

Combined use of crystalline sodium salt and polymeric precipitation inhibitors to improve pharmacokinetic profile of ibuprofen through supersaturation.

PubMed

Terebetski, Jenna L; Cummings, John J; Fauty, Scott E; Michniak-Kohn, Bozena

2014-10-01

To maximize the pharmacological effect of a pain reliever such as ibuprofen, early onset of action is critical. Unfortunately, the acidic nature of ibuprofen minimizes the amount of drug that can be solubilized under gastric conditions and would be available for immediate absorption upon entry into the intestine. Although the sodium salt of ibuprofen has higher solubility, rapid conversion from the salt to the poorly soluble free acid phase occurs under gastric conditions. Therefore, the combination of the highly soluble sodium salt form of ibuprofen with polymers was evaluated as an approach to prolong supersaturation of ibuprofen during the disproportionation of the salt. Binary combinations of ibuprofen sodium with polymers resulted in the identification of several formulations that demonstrated high degrees and extended durations of supersaturation during in vitro dissolution experiments. These formulations included HPMC, polyvinyl pyrrolidone-vinyl acetate copolymer (PVP-VA64), methylcellulose (MC), and hydroxypropyl cellulose (HPC). The in vitro supersaturation observed with these ibuprofen-polymer formulations translated to an increase in Cmax and an earlier Tmax for the PVP-VA64, MC, and HPC formulations relative to ibuprofen only controls when administered orally to rats under fasted conditions. Based on these observations, combining ibuprofen sodium with polymers such as PVP-VA64, MC, or HPC is a viable formulation approach to prolong supersaturation in the stomach and enable an optimized pharmacokinetic profile in vivo where rapid onset of action is desired.

Heat transfer evaluation in a plasma core reactor

NASA Technical Reports Server (NTRS)

Smith, D. E.; Smith, T. M.; Stoenescu, M. L.

1976-01-01

Numerical evaluations of heat transfer in a fissioning uranium plasma core reactor cavity, operating with seeded hydrogen propellant, was performed. A two-dimensional analysis is based on an assumed flow pattern and cavity wall heat exchange rate. Various iterative schemes were required by the nature of the radiative field and by the solid seed vaporization. Approximate formulations of the radiative heat flux are generally used, due to the complexity of the solution of a rigorously formulated problem. The present work analyzes the sensitivity of the results with respect to approximations of the radiative field, geometry, seed vaporization coefficients and flow pattern. The results present temperature, heat flux, density and optical depth distributions in the reactor cavity, acceptable simplifying assumptions, and iterative schemes. The present calculations, performed in cartesian and spherical coordinates, are applicable to any most general heat transfer problem.

Geometric calculus-based postulates for the derivation and extension of the Maxwell equations

NASA Astrophysics Data System (ADS)

McClellan, Gene E.

2012-09-01

Clifford analysis, particularly application of the geometric algebra of three-dimensional physical space and its associated geometric calculus, enables a compact formulation of Maxwell's electromagnetic (EM) equations from a set of physically relevant and mathematically pleasing postulates. This formulation results in a natural extension of the Maxwell equations yielding wave solutions in addition to the usual EM waves. These additional solutions do not contradict experiment and have three properties in common with the apparent properties of dark energy. These three properties are that the wave solutions 1) propagate at the speed of light, 2) do not interact with ordinary electric charges or currents, and 3) possess retrograde momentum. By retrograde momentum, we mean that the momentum carried by such a wave is directed oppositely to the direction of energy transport. A "gas" of such waves generates negative pressure.

Effect of pigment concentration on fastness and color values of thermal and UV curable pigment printing

NASA Astrophysics Data System (ADS)

Baysal, Gulcin; Kalav, Berdan; Karagüzel Kayaoğlu, Burçak

2017-10-01

In the current study, it is aimed to determine the effect of pigment concentration on fastness and colour values of thermal and ultraviolet (UV) curable pigment printing on synthetic leather. For this purpose, thermal curable solvent-based and UV curable water-based formulations were prepared with different pigment concentrations (3, 5 and 7%) separately and applied by screen printing technique using a screen printing machine. Samples printed with solvent-based formulations were thermally cured and samples printed with water-based formulations were cured using a UV curing machine equipped with gallium and mercury (Ga/Hg) lamps at room temperature. The crock fastness values of samples printed with solvent-based formulations showed that increase in pigment concentration was not effective on both dry and wet crock fastness values. On the other hand, in samples printed with UV curable water-based formulations, dry crock fastness was improved and evaluated as very good for all pigment concentrations. However, increasing the pigment concentration affected the wet crock fastness values adversely and lower values were observed. As the energy level increased for each irradiation source, the fastness values were improved. In comparison with samples printed with solvent-based formulations, samples printed with UV curable water-based formulations yielded higher K/S values at all pigment concentrations. The results suggested that, higher K/S values can be obtained in samples printed with UV curable water-based formulations at a lower pigment concentration compared to samples printed with solvent-based formulations.

Monkey search algorithm for ECE components partitioning

NASA Astrophysics Data System (ADS)

Kuliev, Elmar; Kureichik, Vladimir; Kureichik, Vladimir, Jr.

2018-05-01

The paper considers one of the important design problems – a partitioning of electronic computer equipment (ECE) components (blocks). It belongs to the NP-hard class of problems and has a combinatorial and logic nature. In the paper, a partitioning problem formulation can be found as a partition of graph into parts. To solve the given problem, the authors suggest using a bioinspired approach based on a monkey search algorithm. Based on the developed software, computational experiments were carried out that show the algorithm efficiency, as well as its recommended settings for obtaining more effective solutions in comparison with a genetic algorithm.

The meaning, the sense and the significance: translating the science of mesenchymal stem cells into medicine.

PubMed

Bianco, Paolo; Cao, Xu; Frenette, Paul S; Mao, Jeremy J; Robey, Pamela G; Simmons, Paul J; Wang, Cun-Yu

2013-01-01

Mesenchymal stem cells (MSCs) are the focus of intensive efforts worldwide directed not only at elucidating their nature and unique properties but also developing cell-based therapies for a diverse range of diseases. More than three decades have passed since the original formulation of the concept, revolutionary at the time, that multiple connective tissues could emanate from a common progenitor or stem cell retained in the postnatal bone marrow. Despite the many important advances made since that time, substantial ambiguities still plague the field regarding the nature, identity, function, mode of isolation and experimental handling of MSCs. These uncertainties have a major impact on their envisioned therapeutic use.

The use of natural and synthetic phospholipids as pharmaceutical excipients*

PubMed Central

van Hoogevest, Peter; Wendel, Armin

2014-01-01

In pharmaceutical formulations, phospholipids obtained from plant or animal sources and synthetic phospholipids are used. Natural phospholipids are purified from, e.g., soybeans or egg yolk using non-toxic solvent extraction and chromatographic procedures with low consumption of energy and minimum possible waste. Because of the use of validated purification procedures and sourcing of raw materials with consistent quality, the resulting products differing in phosphatidylcholine content possess an excellent batch to batch reproducibility with respect to phospholipid and fatty acid composition. The natural phospholipids are described in pharmacopeias and relevant regulatory guidance documentation of the Food and Drug Administration (FDA) and European Medicines Agency (EMA). Synthetic phospholipids with specific polar head group, fatty acid composition can be manufactured using various synthesis routes. Synthetic phospholipids with the natural stereochemical configuration are preferably synthesized from glycerophosphocholine (GPC), which is obtained from natural phospholipids, using acylation and enzyme catalyzed reactions. Synthetic phospholipids play compared to natural phospholipid (including hydrogenated phospholipids), as derived from the number of drug products containing synthetic phospholipids, a minor role. Only in a few pharmaceutical products synthetic phospholipids are used. Natural phospholipids are used in oral, dermal, and parenteral products including liposomes. Natural phospholipids instead of synthetic phospholipids should be selected as phospholipid excipients for formulation development, whenever possible, because natural phospholipids are derived from renewable sources and produced with more ecologically friendly processes and are available in larger scale at relatively low costs compared to synthetic phospholipids. Practical applications: For selection of phospholipid excipients for pharmaceutical formulations, natural phospholipids are preferred compared to synthetic phospholipids because they are available at large scale with reproducible quality at lower costs of goods. They are well accepted by regulatory authorities and are produced using less chemicals and solvents at higher yields. In order to avoid scale up problems during pharmaceutical development and production, natural phospholipid excipients instead of synthetic phospholipids should be selected whenever possible. PMID:25400504

Pharmaceutical versatility of cationic niosomes derived from amino acid-based surfactants: Skin penetration behavior and controlled drug release.

PubMed

Muzzalupo, Rita; Pérez, Lourdes; Pinazo, Aurora; Tavano, Lorena

2017-08-30

The natural capability shown by cationic vesicles in interacting with negatively charged surfaces or biomolecules has recently attracted increased interest. Important pharmacological advantages include the selective targeting of the tumour vasculature, the promotion of permeation across cell membranes, as well as the influence of cationic vesicles on drug delivery. Accordingly, cationic amphiphiles derived from amino acids may represent an alternative to traditional synthetic cationic surfactants due to their lower cytotoxicity. The importance of a synthesized lysine-based gemini surfactant (labelledC 6 (LL) 2 ) was evaluated in drug delivery by designing cationic niosomes as usable pharmaceutical tools of chemotherapeutics and antibiotics, respectively like methotrexate and tetracycline. The influence of formulation factors on the vesicles' physical-chemical properties, drug entrapment efficiency, in vitro release and ex-vivo skin permeation were investigated. A niosomal gel containing the gemini surfactant was also tested as a viable multi-component topical formulation. Results indicate that in the presence of cholesterol, C 6 (LL) 2 was able to form stable and nanosized niosomes, loading hydrophilic or hydrophobic molecules. Furthermore, in vitro release studies and ex-vivo permeation profiles showed that C 6 (LL) 2 -based vesicles behave as sustained and controlled delivery systems in the case of parenteral administration, and as drug percutaneous permeation enhancers after topical application. Finally, cationic C 6 (LL) 2 acts as a carrier constituent, conferring peculiar and interesting functionality to the final formulation. Copyright © 2017 Elsevier B.V. All rights reserved.

Lallemantia reylenne seeds as superdisintegrant: Formulation and evaluation of nimesulide orodispersible tablets

PubMed Central

Malik, Karan; Arora, Gurpreet; Singh, Inderbir; Arora, Sandeep

2011-01-01

Aim: Orodispersible tablets also known as fast dissolving tablets disintegrate instantaneously within the mouth and thus can be consumed without water. The present study was aimed to formulate orodispersible tablets of nimesulide by using Lallemantia reylenne seeds as natural superdisintegrant. Materials and Methods: Powdered lallemantia seeds were characterized for powder flow properties (bulk density, tapped density, carr's consolidation index, hausner ratio, angle of repose), swelling index, viscosity, pH, and loss on drying. The prepared tablets were evaluated for different tablet parametric tests, wetting time, water absorption ratio, effective pore radius, porosity, packing fraction, in vitro and in vivo disintegration time, in vitro dissolution and stability studies. Results and Discussion: Increase in Lallementia reylenne concentration had an appreciable effect on tablet hardness and friability which clearly indicated binding potential of the seeds. Water absorption ratio increased with increase in Lallemantia reylenne concentration from batch A1 to A4. Water uptake coupled natural polymer swelling could be the most probable mechanism for concentration dependent reduction in disintegration time by the Lallemantia reylenne seeds. Porosity of the formulated tablets was found to increase from batch A1-A4. The in vitro disintegration results were in line with in vivo disintegration results. Conclusion: It could be concluded that Lallemantia reylenne seeds could be used as natural superdisintegrant in the formulation of orodispersible tablets. PMID:23071942

A chance constraint estimation approach to optimizing resource management under uncertainty

Treesearch

Michael Bevers

2007-01-01

Chance-constrained optimization is an important method for managing risk arising from random variations in natural resource systems, but the probabilistic formulations often pose mathematical programming problems that cannot be solved with exact methods. A heuristic estimation method for these problems is presented that combines a formulation for order statistic...

Evaluation of the Abington isolate of the gypsy moth nuclear polyhedrosis virus against a formulation of Gypchek in small field plots

Treesearch

R. E. Webb; M. Shapiro; J. D. Podgwaite; D. D. Cohen; R. L. Ridgway

1991-01-01

The "Abington" isolate of the nuclear polyhedrosis virus (NPV) of the gypsy moth (Lymantria dispar L.) was compared with a formulation of Gypchek against a natural gypsy moth population in the Swallow Falls State Forest in Garrett County, MD.

Microfluidics: a transformational tool for nanomedicine development and production.

PubMed

Garg, Shyam; Heuck, Gesine; Ip, Shell; Ramsay, Euan

2016-11-01

Microfluidic devices are mircoscale fluidic circuits used to manipulate liquids at the nanoliter scale. The ability to control the mixing of fluids and the continuous nature of the process make it apt for solvent/antisolvent precipitation of drug-delivery nanoparticles. This review describes the use of numerous microfluidic designs for the formulation and production of lipid nanoparticles, liposomes and polymer nanoparticles to encapsulate and deliver small molecule or genetic payloads. The advantages of microfluidics are illustrated through examples from literature comparing conventional processes such as beaker and T-tube mixing to microfluidic approaches. Particular emphasis is placed on examples of microfluidic nanoparticle formulations that have been tested in vitro and in vivo. Fine control of process parameters afforded by microfluidics, allows unprecedented optimization of nanoparticle quality and encapsulation efficiency. Automation improves the reproducibility and optimization of formulations. Furthermore, the continuous nature of the microfluidic process is inherently scalable, allowing optimization at low volumes, which is advantageous with scarce or costly materials, as well as scale-up through process parallelization. Given these advantages, microfluidics is poised to become the new paradigm for nanomedicine formulation and production.

FIRETEC: A transport description of wildfire behavior

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

Linn, R.R.; Harlow, F.H.

1997-12-01

Wildfires are a threat to human life and property, yet they are an unavoidable part of nature and in some instances they are necessary for the natural maintenance and evolution of forests. Investigators have attempted to describe the behavior (speed, direction, modes of spread) of wildfires for over fifty years. Current models for numerical description are mainly algebraic and based on statistical or empirical ideas. The authors describe, in contrast, a transport model called FIRETEC, which is a self-determining fire behavior model. The use of transport formulations connects the propagation rates to the full conservation equations for energy, momentum, speciesmore » concentrations, mass, and turbulence. In this text, highlights of the model formulation and results are described. The goal of the FIRETEC model is to describe average behavior of the gases and fuels. It represents the essence of the combination of many small-scale processes without resolving each process in complete detail. The FIRETEC model is implemented into a computer code that examines line-fire propagation in a vertical spatial cut parallel to the direction of advancement. With this code the authors are able to examine wind effects, slope effects, and the effects of nonhomogeneous fuel distribution.« less

An RBF-FD closest point method for solving PDEs on surfaces

NASA Astrophysics Data System (ADS)

Petras, A.; Ling, L.; Ruuth, S. J.

2018-10-01

Partial differential equations (PDEs) on surfaces appear in many applications throughout the natural and applied sciences. The classical closest point method (Ruuth and Merriman (2008) [17]) is an embedding method for solving PDEs on surfaces using standard finite difference schemes. In this paper, we formulate an explicit closest point method using finite difference schemes derived from radial basis functions (RBF-FD). Unlike the orthogonal gradients method (Piret (2012) [22]), our proposed method uses RBF centers on regular grid nodes. This formulation not only reduces the computational cost but also avoids the ill-conditioning from point clustering on the surface and is more natural to couple with a grid based manifold evolution algorithm (Leung and Zhao (2009) [26]). When compared to the standard finite difference discretization of the closest point method, the proposed method requires a smaller computational domain surrounding the surface, resulting in a decrease in the number of sampling points on the surface. In addition, higher-order schemes can easily be constructed by increasing the number of points in the RBF-FD stencil. Applications to a variety of examples are provided to illustrate the numerical convergence of the method.

Carrageenan: a natural seaweed polysaccharide and its applications.

PubMed

Prajapati, Vipul D; Maheriya, Pankaj M; Jani, Girish K; Solanki, Himanshu K

2014-05-25

Polysaccharides have been gaining interesting and valuable applications in the food and pharmaceutical fields. As they are derived from the natural source, they are easily available, non-toxic, cheap, biodegradable and biocompatible. Carrageenan is one among them, which fulfills the criteria of polysaccharide; it is a natural carbohydrate (polysaccharide) obtained from edible red seaweeds. The name Carrageenan is derived from the Chondrus crispus species of seaweed (Rhodophyceace) known as Carrageen Moss or Irish Moss, and Carraigin. A demand based on its application has been widely increasing in food and pharmaceutical sectors. Carrageenan has gained wide applications in experimental medicine, pharmaceutical formulations, cosmetics, and food industries. Through keen references of the reported literature on carrageenan, in this review, we have described about carrageenan, its properties, extraction and refining, and its food and pharmaceutical applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

Applications of lipid based formulation technologies in the delivery of biotechnology-based therapeutics.

PubMed

du Plessis, Lissinda H; Marais, Etienne B; Mohammed, Faruq; Kotzé, Awie F

2014-01-01

In the last decades several new biotechnologically-based therapeutics have been developed due to progress in genetic engineering. A growing challenge facing pharmaceutical scientists is formulating these compounds into oral dosage forms with adequate bioavailability. An increasingly popular approach to formulate biotechnology-based therapeutics is the use of lipid based formulation technologies. This review highlights the importance of lipid based drug delivery systems in the formulation of oral biotechnology based therapeutics including peptides, proteins, DNA, siRNA and vaccines. The different production procedures used to achieve high encapsulation efficiencies of the bioactives are discussed, as well as the factors influencing the choice of excipient. Lipid based colloidal drug delivery systems including liposomes and solid lipid nanoparticles are reviewed with a focus on recent advances and updates. We further describe microemulsions and self-emulsifying drug delivery systems and recent findings on bioactive delivery. We conclude the review with a few examples on novel lipid based formulation technologies.

Influence of the Drilling Mud Formulation Process on the Bacterial Communities in Thermogenic Natural Gas Wells of the Barnett Shale▿†

PubMed Central

Struchtemeyer, Christopher G.; Davis, James P.; Elshahed, Mostafa S.

2011-01-01

The Barnett Shale in north central Texas contains natural gas generated by high temperatures (120 to 150°C) during the Mississippian Period (300 to 350 million years ago). In spite of the thermogenic origin of this gas, biogenic sulfide production and microbiologically induced corrosion have been observed at several natural gas wells in this formation. It was hypothesized that microorganisms in drilling muds were responsible for these deleterious effects. Here we collected drilling water and drilling mud samples from seven wells in the Barnett Shale during the drilling process. Using quantitative real-time PCR and microbial enumerations, we show that the addition of mud components to drilling water increased total bacterial numbers, as well as the numbers of culturable aerobic heterotrophs, acid producers, and sulfate reducers. The addition of sterile drilling muds to microcosms that contained drilling water stimulated sulfide production. Pyrosequencing-based phylogenetic surveys of the microbial communities in drilling waters and drilling muds showed a marked transition from typical freshwater communities to less diverse communities dominated by Firmicutes and Gammaproteobacteria. The community shifts observed reflected changes in temperature, pH, oxygen availability, and concentrations of sulfate, sulfonate, and carbon additives associated with the mud formulation process. Finally, several of the phylotypes observed in drilling muds belonged to lineages that were thought to be indigenous to marine and terrestrial fossil fuel formations. Our results suggest a possible alternative exogenous origin of such phylotypes via enrichment and introduction to oil and natural gas reservoirs during the drilling process. PMID:21602366

Influence of the drilling mud formulation process on the bacterial communities in thermogenic natural gas wells of the Barnett Shale.

PubMed

Struchtemeyer, Christopher G; Davis, James P; Elshahed, Mostafa S

2011-07-01

The Barnett Shale in north central Texas contains natural gas generated by high temperatures (120 to 150°C) during the Mississippian Period (300 to 350 million years ago). In spite of the thermogenic origin of this gas, biogenic sulfide production and microbiologically induced corrosion have been observed at several natural gas wells in this formation. It was hypothesized that microorganisms in drilling muds were responsible for these deleterious effects. Here we collected drilling water and drilling mud samples from seven wells in the Barnett Shale during the drilling process. Using quantitative real-time PCR and microbial enumerations, we show that the addition of mud components to drilling water increased total bacterial numbers, as well as the numbers of culturable aerobic heterotrophs, acid producers, and sulfate reducers. The addition of sterile drilling muds to microcosms that contained drilling water stimulated sulfide production. Pyrosequencing-based phylogenetic surveys of the microbial communities in drilling waters and drilling muds showed a marked transition from typical freshwater communities to less diverse communities dominated by Firmicutes and Gammaproteobacteria. The community shifts observed reflected changes in temperature, pH, oxygen availability, and concentrations of sulfate, sulfonate, and carbon additives associated with the mud formulation process. Finally, several of the phylotypes observed in drilling muds belonged to lineages that were thought to be indigenous to marine and terrestrial fossil fuel formations. Our results suggest a possible alternative exogenous origin of such phylotypes via enrichment and introduction to oil and natural gas reservoirs during the drilling process.

Curcumin phytosomal softgel formulation: Development, optimization and physicochemical characterization.

PubMed

Allam, Ahmed N; Komeil, Ibrahim A; Abdallah, Ossama Y

2015-09-01

Curcumin, a naturally occurring lipophilic molecule can exert multiple and diverse bioactivities. However, its limited aqueous solubility and extensive presystemic metabolism restrict its bioavailability. Curcumin phytosomes were prepared by a simple solvent evaporation method where free flowing powder was obtained in addition to a newly developed semisolid formulation to increase curcumin content in softgels. Phytosomal powder was characterized in terms of drug content and zeta potential. Thirteen different softgel formulations were developed using oils such as Miglyol 812, castor oil and oleic acid, a hydrophilic vehicle such as PEG 400 and bioactive surfactants such as Cremophor EL and KLS P 124. Selected formulations were characterized in terms of curcumin in vitro dissolution. TEM analysis revealed good stability and a spherical, self-closed structure of curcumin phytosomes in complex formulations. Stability studies of chosen formulations prepared using the hydrophilic vehicle revealed a stable curcumin dissolution pattern. In contrast, a dramatic decrease in curcumin dissolution was observed in case of phytosomes formulated in oily vehicles.

Plasma pharmacokinetics, faecal excretion and efficacy of pyrantel pamoate paste and granule formulations following per os administration in donkeys naturally infected with intestinal strongylidae.

PubMed

Gokbulut, Cengiz; Aksit, Dilek; Smaldone, Giorgio; Mariani, Ugo; Veneziano, Vincenzo

2014-09-15

The plasma disposition, faecal excretion and efficacy of two formulations of pyrantel pamoate in donkeys were examined in a controlled trial. Three groups of seven donkeys received either no medication (control) or pyrantel paste or granule formulations at horse dosage of 20mg/kg B.W. (equals 6.94 mg/kg PYR base) of body weight. Heparinized blood and faecal samples were collected at various times between 1 and 144 h after treatment. The samples were analysed by high-performance liquid chromatography. The last detectable plasma concentration (tmax) of paste formulation was significantly earlier (36.00 h) compared with granule formulation (46.29 h). Although, there was no significant difference on terminal half lives (t1/2: 12.39 h vs. 14.86 h), tmax (14.86 h vs. 14.00) and MRT (24.80 h vs. 25.44 h) values; the Cmax (0.09 μg/ml) AUC (2.65 μgh/ml) values of paste formulation were significantly lower and smaller compared with those of granule formulation (0.21 μg/ml and 5.60 μgh/ml), respectively. The highest dry faecal concentrations were 710.46 μg/g and 537.21 μg/g and were determined at 48 h for both paste and granule formulation of PYR in donkeys, respectively. Pre-treatment EPG of 1104, 1061 and 1139 were observed for the control, PYR paste and PYR granule groups, respectively. Pre-treatment EPG were not significantly different (P>0.1) between groups. Post-treatment EPG for both PYR treatment groups were significantly different (P<0.001) from the control group until day 35. Following treatments the PYR formulations were efficient (>95% efficacy) until day 28. In all studied donkeys, coprocultures performed at day-3 revealed the presence of Cyathostomes, S. vulgaris. Faecal cultures performed on different days from C-group confirmed the presence of the same genera. Coprocultures from treated animals revealed the presence of few larvae of Cyathostomes. Copyright © 2014 Elsevier B.V. All rights reserved.

Novel isotretinoin microemulsion-based gel for targeted topical therapy of acne: formulation consideration, skin retention and skin irritation studies

NASA Astrophysics Data System (ADS)

Patel, Mrunali R.; Patel, Rashmin B.; Parikh, Jolly R.; Patel, Bharat G.

2016-04-01

Isotretinoin was formulated in novel microemulsion-based gel formulation with the aim of improving its solubility, skin tolerability, therapeutic efficacy, skin-targeting efficiency and patient compliance. Microemulsion was formulated by the spontaneous microemulsification method using 8 % isopropyl myristate, 24 % Labrasol, 8 % plurol oleique and 60 % water as an external phase. All plain and isotretinoin-loaded microemulsions were clear and showed physicochemical parameters for the desired topical delivery and stability. The permeation profiles of isotretinoin through rat skin from selected microemulsion formulation followed zero-order kinetics. Microemulsion-based gel was prepared by incorporating Carbopol®971 in optimized microemulsion formulation having suitable skin permeation rate and skin uptake. Microemulsion-based gel showed desired physicochemical parameters and demonstrated advantage over marketed formulation in improving the skin tolerability of isotretinoin, indicating its potential in improving topical delivery of isotretinoin. The developed microemulsion-based gel may be a potential drug delivery vehicle for targeted topical delivery of isotretinoin in the treatment of acne.

Text Categorization for Multi-Page Documents: A Hybrid Naive Bayes HMM Approach.

ERIC Educational Resources Information Center

Frasconi, Paolo; Soda, Giovanni; Vullo, Alessandro

Text categorization is typically formulated as a concept learning problem where each instance is a single isolated document. This paper is interested in a more general formulation where documents are organized as page sequences, as naturally occurring in digital libraries of scanned books and magazines. The paper describes a method for classifying…

Toxicity and feeding response of adult corn earworm (Lepidoptera: Noctuidae) to an organic spinosad formulation in sucrose solution

USDA-ARS?s Scientific Manuscript database

Adult corn earworm, Helicoverpa zea (Boddie), feeds on plant exudates soon after emergence from pupa in their natural habitat, and thereafter disperses to suitable host plants for reproduction. The intent of this study was to determine if Entrust™, an organic formulation of spinosad, could be used i...

Formulation and evaluation of controlled release matrix mucoadhesive tablets of domperidone using Salvia plebeian gum

PubMed Central

Arora, Gurpreet; Malik, Karan; Singh, Inderbir; Arora, Sandeep; Rana, Vikas

2011-01-01

The aim of study was to prepare controlled release matrix mucoadhesive tablets of domperidone using Salvia plebeian gum as natural polymer. Tablets were formulated by direct compression technology employing the natural polymer in different concentrations (5, 10, 15 and 20% w/w). The prepared batches were evaluated for drug assay, diameter, thickness, hardness and tensile strength, swelling index, mucoadhesive strength (using texture analyzer) and subjected to in vitro drug release studies. Real-time stability studies were also conducted on prepared batches. In vitro drug release data were fitted in various release kinetic models for studying the mechanism of drug release. Tensile strength was found to increase from 0.808 ± 0.098 to 1.527 ± 0.10 mN/cm2 and mucoadhesive strength increased from 13.673 ± 1.542 to 40.378 ± 2.345 N, with an increase in the polymer concentration from 5 to 20% (A1 to A4). Swelling index was reported to increase with both increase in the concentration of gum and the time duration. The in vitro drug release decreased from 97.76 to 83.4% (A1 to A4) with the increase in polymer concentration. The drug release from the matrix tablets was found to follow zero-order and Higuchi models, indicating the matrix-forming potential of natural polymer. The value of n was found to be between 0.5221 and 0.8992, indicating the involvement of more than one drug release mechanism from the formulation and possibly the combination of both diffusion and erosion. These research findings clearly indicate the potential of S. plebeian gum to be used as binder, release retardant and mucoadhesive natural material in tablet formulations. PMID:22171313

Sensory analysis of cosmetic powders: personal care ingredients and emulsions.

PubMed

Moussour, M; Lavarde, M; Pensé-Lhéritier, A-M; Bouton, F

2017-02-01

The powders are ingredients increasingly used in the formulation of cosmetic products for the sensory qualities they give. The objective of this study was the development of a lexicon and a referential for sensory characterization of these pure raw materials as well as formulations which contain them. Eleven expert panellists from Ecole de biologie industrielle de Cergy (France) developed a lexicon and a referential based on 12 powders of different chemical natures. The selected attributes were then used for performing a quantitative descriptive profile of two powders and an emulsion containing or not one of these two powders. A lexicon has been established through a consensus approach of the panel. It contains seven attributes that allow the evaluation of the powders in four phases: the appearance, the pickup, the application and the after-feel. This lexicon contains definitions and assessment protocols and provides references products. The quantitative descriptive profile of two powders of the same chemical nature, but different in physical quality showed significant differences in sensory level between products. These same attributes used to evaluate an emulsion containing the powder or not allowed to prove the contribution of these raw materials on the sensory specificities of the emulsion. The lexicon developed in this study can be used for assessment of other powders but also to define the quantities necessary to put in the formulation to meet the sensory characteristics of these raw materials powder. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Natural and synthetic polymers in fabric and home care applications

NASA Astrophysics Data System (ADS)

Paderes, Monissa; Ahirwal, Deepak; Fernández Prieto, Susana

2017-07-01

Polymers can be tailored to provide different benefits in Fabric & Home Care formulations depending on the monomers and modifications used, such as avoiding dye transfer inhibition in the wash, modifying the surface of tiles or increasing the viscosity and providing suspension properties to consumer products. Specifically, the rheology modification properties of synthetic and natural polymers are discussed in this chapter. The choice of a polymeric rheology modifier will depend on the formulation ingredients (charges, functional groups), the type and the amount of surfactants, the pH and the desired rheology modification. Natural polymeric rheology modifiers have been traditionally used in the food industry, being xanthan gum one of the most well-known ones. On the contrary, synthetic rheology modifiers are preferably used in paints & coats, textile printing and cleaning products.

Formulation design for topical drug and nanoparticle treatment of skin disease.

PubMed

Raphael, Anthony P; Garrastazu, Gabriela; Sonvico, Fabio; Prow, Tarl W

2015-02-01

The skin has evolved to resist the penetration of foreign substances and particles. Topical therapeutic and cosmeceutical delivery is a growing field founded on selectively overcoming this barrier. Both the biology of the skin and the nature of the formulation/active ingredient must be aligned for efficient transcutaneous delivery. This review discusses the biological changes in the skin barrier that occur with common dermatological conditions. This context is the foundation for the discussion of formulation strategies to improve penetration profiles of common active ingredients in dermatology. Finally, we compare and contrast those approaches to recent advances described in the research literature with an eye toward the future of topical formulation design.

Resilient Urban Infrastructures - Basics of Smart Sustainable Cities

NASA Astrophysics Data System (ADS)

Timashev, S. A.

2017-11-01

In this paper the notion of urban infrastructure resilience is formulated being expressed verbally and strictly in conditional probability terms. It is further used to formulate several most important features of a smart city. This multidisciplinary and multifaceted approach is used to explain the concept of quantitative resilience in urban design, operation, managing urban risk and mitigating of the consequences of a natural or industrial disaster. The extremely urgent problem is formulated on how to connect the physical and spatial (core) resiliencies with the functional, organizational, economic and social resiliencies.

A general transformation to canonical form for potentials in pairwise interatomic interactions.

PubMed

Walton, Jay R; Rivera-Rivera, Luis A; Lucchese, Robert R; Bevan, John W

2015-06-14

A generalized formulation of explicit force-based transformations is introduced to investigate the concept of a canonical potential in both fundamental chemical and intermolecular bonding. Different classes of representative ground electronic state pairwise interatomic interactions are referenced to a chosen canonical potential illustrating application of such transformations. Specifically, accurately determined potentials of the diatomic molecules H2, H2(+), HF, LiH, argon dimer, and one-dimensional dissociative coordinates in Ar-HBr, OC-HF, and OC-Cl2 are investigated throughout their bound potentials. Advantages of the current formulation for accurately evaluating equilibrium dissociation energies and a fundamentally different unified perspective on nature of intermolecular interactions will be emphasized. In particular, this canonical approach has significance to previous assertions that there is no very fundamental distinction between van der Waals bonding and covalent bonding or for that matter hydrogen and halogen bonds.

Formulation and Evaluation of Exotic Fat Based Cosmeceuticals for Skin Repair

PubMed Central

Mandawgade, S. D.; Patravale, Vandana B.

2008-01-01

Mango butter was explored as a functional, natural supplement and active skin ingredient in skin care formulations. A foot care cream was developed with mango butter to evaluate its medicinal value and protective function in skin repair. Qualitative comparison and clinical case studies of the product were carried out. Wound healing potential of foot care cream was investigated on the rat excision and incision wound models. Results of the clinical studies demonstrated complete repair of worn and cracked skin in all the human volunteers. Furthermore, foot care cream exhibited significant healing response in both the wound models. The project work could be concluded as establishment of high potential for mango butter to yield excellent emolliency for better skin protection. Improving the product features and medicinal functionality further validate mango butter as a specialty excipient in development of cosmeceuticals and has an immense value for its commercialization. PMID:20046792

Development of a direct three-dimensional biomicrofabrication concept based on electrospraying a custom made siloxane sol

PubMed Central

Sullivan, Alice C.; Jayasinghe, Suwan N.

2007-01-01

We demonstrate here the discovery of a unique and direct three-dimensional biomicrofabrication concept possessing the ability to revolutionize the jet-based fabrication arena. Previous work carried out on similar jet-based approaches have been successful in fabricating only vertical wall∕pillar-structures by the controlled deposition of stacked droplets. However, these advanced jet-techniques have not been able to directly fabricate self-supporting arches∕links (without molds or reaction methods) between adjacent structures (walls or pillars). Our work reported here gives birth to a unique type of jet determined by high intensity electric fields, which is derived from a specially formulated siloxane sol. The sol studied here has been chosen for its attractive properties (such as an excellent cross-linking nature as well as the ability to polymerize via polycondensation on deposition to its biocompatability), which promotes direct forming of biostructures with nanometer (<50 nm) sized droplets in three dimensions. We foresee that this direct three-dimensional biomicrofabrication jet technique coupled with a variety of formulated sols having focused and enhanced functionality will be explored throughout the physical and life sciences. PMID:19693359

Development and Sequential Analysis of a New Multi-Agent, Anti-Acne Formulation Based on Plant-Derived Antimicrobial and Anti-Inflammatory Compounds.

PubMed

Saviuc, Crina; Ciubucă, Bianca; Dincă, Gabriela; Bleotu, Coralia; Drumea, Veronica; Chifiriuc, Mariana-Carmen; Popa, Marcela; Gradisteanu Pircalabioru, Gratiela; Marutescu, Luminita; Lazăr, Veronica

2017-01-17

The antibacterial and anti-inflammatory potential of natural, plant-derived compounds has been reported in many studies. Emerging evidence indicates that plant-derived essential oils and/or their major compounds may represent a plausible alternative treatment for acne, a prevalent skin disorder in both adolescent and adult populations. Therefore, the purpose of this study was to develop and subsequently analyze the antimicrobial activity of a new multi-agent, synergic formulation based on plant-derived antimicrobial compounds (i.e., eugenol, β-pinene, eucalyptol, and limonene) and anti-inflammatory agents for potential use in the topical treatment of acne and other skin infections. The optimal antimicrobial combinations selected in this study were eugenol/β-pinene/salicylic acid and eugenol/β-pinene/2-phenoxyethanol/potassium sorbate. The possible mechanisms of action revealed by flow cytometry were cellular permeabilization and inhibition of efflux pumps activity induced by concentrations corresponding to sub-minimal inhibitory (sub-MIC) values. The most active antimicrobial combination represented by salycilic acid/eugenol/β-pinene/2-phenoxyethanol/potassium sorbate was included in a cream base, which demonstrated thermodynamic stability and optimum microbiological characteristics.

An Extrusion Spheronization Approach to Enable a High Drug Load Formulation of a Poorly Soluble Drug with a Low Melting Surfactant.

PubMed

Tatavarti, Aditya; Kesisoglou, Filippos

2015-11-01

Vitamin E tocopherol polyethylene glycol succinate (TPGS) is a non-ionic surface active agent, known to enhance the bioavailability of lipophilic compounds via wettability, solubility, and in some cases permeability enhancement. MK-0536 is an anti-retroviral drug with poor wettability and solubility and a high dose. Based on pharmacokinetic studies in dogs and humans, use of vitamin E TPGS in oral solid formulations of MK-0536 provides desired PK characteristics. The use of vitamin E TPGS, however, in solid dosage forms is limited because of the processing challenges resulting from its waxy nature and low melting temperature (∼37°C). The current study, for the first time, demonstrates the use of an alternative low pressure extrusion and spheronization approach to enable high loadings of the poorly soluble, poorly compactable drug and relatively high levels of vitamin E TPGS. This approach not only aided in mitigating processing challenges arising from most high energy process steps such as milling, compression, and coating, but also enabled a higher drug load formulation that provided superior bioperformance relative to a conventional high shear wet granulated formulation. An encapsulated dosage form consisting of pellets prepared by extrusion spheronization with 75% (w/w) MK-0536 and 10% (w/w) vitamin E TPGS was developed. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

The Use of D-Optimal Mixture Design in Optimising Okara Soap Formulation for Stratum Corneum Application

PubMed Central

Borhan, Farrah Payyadhah; Abd Gani, Siti Salwa; Shamsuddin, Rosnah

2014-01-01

Okara, soybean waste from tofu and soymilk production, was utilised as a natural antioxidant in soap formulation for stratum corneum application. D-optimal mixture design was employed to investigate the influence of the main compositions of okara soap containing different fatty acid and oils (virgin coconut oil A (24–28% w/w), olive oil B (15–20% w/w), palm oil C (6–10% w/w), castor oil D (15–20% w/w), cocoa butter E (6–10% w/w), and okara F (2–7% w/w)) by saponification process on the response hardness of the soap. The experimental data were utilized to carry out analysis of variance (ANOVA) and to develop a polynomial regression model for okara soap hardness in terms of the six design factors considered in this study. Results revealed that the best mixture was the formulation that included 26.537% A, 19.999% B, 9.998% C, 16.241% D, 7.633% E, and 7.000% F. The results proved that the difference in the level of fatty acid and oils in the formulation significantly affects the hardness of soap. Depending on the desirable level of those six variables, creation of okara based soap with desirable properties better than those of commercial ones is possible. PMID:25548777

Model-Based Prognostics of Hybrid Systems

NASA Technical Reports Server (NTRS)

Daigle, Matthew; Roychoudhury, Indranil; Bregon, Anibal

2015-01-01

Model-based prognostics has become a popular approach to solving the prognostics problem. However, almost all work has focused on prognostics of systems with continuous dynamics. In this paper, we extend the model-based prognostics framework to hybrid systems models that combine both continuous and discrete dynamics. In general, most systems are hybrid in nature, including those that combine physical processes with software. We generalize the model-based prognostics formulation to hybrid systems, and describe the challenges involved. We present a general approach for modeling hybrid systems, and overview methods for solving estimation and prediction in hybrid systems. As a case study, we consider the problem of conflict (i.e., loss of separation) prediction in the National Airspace System, in which the aircraft models are hybrid dynamical systems.

Antioxidant films based on cross-linked methyl cellulose and native Chilean berry for food packaging applications.

PubMed

López de Dicastillo, Carol; Rodríguez, Francisco; Guarda, Abel; Galotto, Maria José

2016-01-20

Development of antioxidant and antimicrobial active food packaging materials based on biodegradable polymer and natural plant extracts has numerous advantages as reduction of synthetic additives into the food, reduction of plastic waste, and food protection against microorganisms and oxidation reactions. In this way, active films based on methylcellulose (MC) and maqui (Aristotelia chilensis) berry fruit extract, as a source of antioxidants agents, were studied. On the other hand, due to the high water affinity of MC, this polymer was firstly cross-linked with glutaraldehyde (GA) at different concentrations. The results showed that the addition of GA decreased water solubility, swelling, water vapor permeability of MC films, and the release of antioxidant substances from the active materials increased with the concentration of GA. Natural extract and active cross-linked films were characterized in order to obtain the optimal formulation with the highest antioxidant activity and the best physical properties for latter active food packaging application. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Role of Soundscape in Nature-Based Rehabilitation: A Patient Perspective.

PubMed

Cerwén, Gunnar; Pedersen, Eja; Pálsdóttir, Anna-María

2016-12-11

Nature-based rehabilitation (NBR) has convincing support in research, yet the underlying mechanisms are not fully understood. The present study sought to increase understanding of the role of soundscapes in NBR, an aspect paid little attention thus far. Transcribed interviews with 59 patients suffering from stress-related mental disorders and undergoing a 12-week therapy programme in the rehabilitation garden in Alnarp, Sweden, were analysed using Interpretative Phenomenology Analysis (IPA). Described sounds were categorised as natural, technological or human. The results showed that patients frequently referred to natural sounds as being part of a pleasant and "quiet" experience that supported recovery and induced "soft fascination". Technological sounds were experienced as disturbing, while perception of human sounds varied depending on loudness and the social context. The study further uncovered how sound influenced patients' behaviour and experiences in the garden, through examination of three cross-theme dimensions that materialised in the study; sound in relation to overall perception, sound in relation to garden usage, and increased susceptibility to sound. The findings are discussed in relation to NBR; the need for a more nuanced understanding of susceptibility to sound among people suffering from mental fatigue was identified and design considerations for future rehabilitation gardens were formulated.

Formulation and optimization of coated PLGA – Zidovudine nanoparticles using factorial design and in vitro in vivo evaluations to determine brain targeting efficiency

PubMed Central

Peter Christoper, G.V.; Vijaya Raghavan, C.; Siddharth, K.; Siva Selva Kumar, M.; Hari Prasad, R.

2013-01-01

In the current study zidovudine loaded PLGA nanoparticles were prepared, coated and further investigated for its effectiveness in brain targeting. IR and DSC studies were performed to determine the interaction between excipients used and to find out the nature of drug in the formulation. Formulations were prepared by adopting 23 factorial designs to evaluate the effects of process and formulation variables. The prepared formulations were subjected for in vitro and in vivo evaluations. In vitro evaluations showed particle size below 100 nm, entrapment efficiency of formulations ranges of 28–57%, process yield of 60–76% was achieved and drug release for the formulations were in the range of 50–85%. The drug release from the formulations was found to follow Higuchi release pattern, n–value obtained after Korsemeyer plot was in the range of 0.56–0.78. In vivo evaluations were performed in mice after intraperitoneal administration of zidovudine drug solution, uncoated and coated formulation. Formulation when coated with Tween 80 achieved a higher concentration in the brain than that of the drug in solution and of the uncoated formulation. Stability studies indicated that there was no degradation of the drug in the formulation after 90 days of preparation when stored in refrigerated condition. PMID:24648825

Preparation and Characterization of Azadirachtin Alginate-Biosorbent Based Formulations: Water Release Kinetics and Photodegradation Study.

PubMed

Flores-Céspedes, Francisco; Martínez-Domínguez, Gerardo P; Villafranca-Sánchez, Matilde; Fernández-Pérez, Manuel

2015-09-30

The botanical insecticide azadirachtin was incorporated in alginate-based granules to obtain controlled release formulations (CRFs). The basic formulation [sodium alginate (1.47%) - azadirachtin (0.28%) - water] was modified by the addition of biosorbents, obtaining homogeneous hybrid hydrogels with high azadirachtin entrapment efficiency. The effect on azadirachtin release rate caused by the incorporation of biosorbents such as lignin, humic acid, and olive pomace in alginate formulation was studied by immersion of the granules in water under static conditions. The addition of the biosorbents to the basic alginate formulation reduces the rate of release because the lignin-based formulation produces a slower release. Photodegradation experiments showed the potential of the prepared formulations in protecting azadirachtin against simulated sunlight, thus improving its stability. The results showed that formulation prepared with lignin provided extended protection. Therefore, this study provides a new procedure to encapsulate the botanical insecticide azadirachtin, improving its delivery and photostability.

On the Miller-Tucker-Zemlin Based Formulations for the Distance Constrained Vehicle Routing Problems

NASA Astrophysics Data System (ADS)

Kara, Imdat

2010-11-01

Vehicle Routing Problem (VRP), is an extension of the well known Traveling Salesman Problem (TSP) and has many practical applications in the fields of distribution and logistics. When the VRP consists of distance based constraints it is called Distance Constrained Vehicle Routing Problem (DVRP). However, the literature addressing on the DVRP is scarce. In this paper, existing two-indexed integer programming formulations, having Miller-Tucker-Zemlin based subtour elimination constraints, are reviewed. Existing formulations are simplified and obtained formulation is presented as formulation F1. It is shown that, the distance bounding constraints of the formulation F1, may not generate the distance traveled up to the related node. To do this, we redefine the auxiliary variables of the formulation and propose second formulation F2 with new and easy to use distance bounding constraints. Adaptation of the second formulation to the cases where new restrictions such as minimal distance traveled by each vehicle or other objectives such as minimizing the longest distance traveled is discussed.

Anti-inflammatory effect of combined tetramethylpyrazine, resveratrol and curcumin in vivo.

PubMed

Chen, Long; Liu, Tianjun; Wang, Qiangsong; Liu, Juan

2017-04-27

Resveratrol and curcumin, as natural flavones products, have good therapeutic effect in acute and chronic inflammation; on the other hand, tetramethylpyrazine (TMP) has angiogenesis and vessel protection effect as well as anti-inflammatory function. In this paper, the anti-inflammatory effect of the tetramethylpyrazine, resveratrol and curcumin (TRC) combination in acute and chronic inflammation was reported in vivo. The dose of the combined three natural products was optimized based on the acute paw swelling mouse model with a Uniform Design methodology. The therapeutic effect of TRC combination on chronic inflammation was investigated by using the collagen-induced arthritis (CIA) rat model based upon the following indexes: the volume of paw swelling, arthritis score, serum mediators and histological examination as well as immunohistochemical staining. The levels of alanine aminotransferase (ALT) and aspartate transaminase (AST) in serum were measured and the pathological sections of liver and kidney were analysed. LD 50 was measured based on the acute oral toxicity (AOT) standard method. The best formulation was the three components combined at the same mass proportion revealed by the Uniform Design methodology. This combination could significantly reduce the paw swelling in acute paw swelling mouse model, could reduce paw swelling and alleviate the damage in joint structural of ankle, cartilages and fibrous tissue in CIA rat model. The dose relationship was clear in both cases. Immunohistochemical staining of ankle tissue revealed that TRC combination was able to inhibit the expression of NF-κB p65 and TNF-α which were closely related to the inflammatory process. Analysis of serum mediators revealed TRC combination could inhibit the production of TNF-α, IL-1β, and IL-6 in the serum. Toxic study revealed this formulation was low toxic, LD 50 was larger than 5 g/kg, both the level of ALT and AST and histopathology in the liver and kidney exhibited no distinctions between the TRC combination and the blank group, no mortality occurred at the administered doses of 5 g/kg. The results showed this formulation could provide a novel potent treatment for acute and chronic inflammation (RA) without side effect like gastric injury occurring in NSAIDs.

Bioactivation antioxidant and transglycating properties of N-acetylcarnosine autoinduction prodrug of a dipeptide L-carnosine in mucoadhesive drug delivery eye-drop formulation: powerful eye health application technique and therapeutic platform.

PubMed

Babizhayev, Mark A

2012-06-01

A considerable interest in N-acetylcarnosine ocular drug design for eye health is based on clinical strategies to improve ocular drug delivery through metabolic enzymatic activation. Human biology aspects of ocular N-acetylcarnosine deacetylation during its pass through the cornea to the aqueous humor and dipeptide hydrolyzing enzymes are characterized. Novel approaches to ocular drug delivery increasing intraocular bioavailability of N-acetylcarnosine biologically activated metabolite carnosine become an integral development ensuring prolonged retention of the medication in the mucoadhesive precorneal area and facilitating transcorneal penetration of the natural dipeptide with the corneal promoters. A comprehensive list of techniques for peptide drug design, synthesis, purification, and biological analyses was considered: liquid chromatography (LC), high performance liquid chromatography (HPLC), (1) H and (13) C nuclear magnetic resonance (NMR), electrospray ionization (ESI) mass spectroscopy, and spectrophotometry. The antioxidant activity of therapeutics-targeted molecules was studied in aqueous solution and in a lipid membrane environment. A deglycation therapeutic system was developed involving removal, by transglycation of sugar or aldehyde moieties from Schiff bases by histidyl-hydrazide compounds or aldehyde scavenger L-carnosine. Clinical studies included ophthalmoscopy, visual acuity (VA), halometer disability glare tests, slit-image, and retro-illumination photography. N-acetylcarnosine 1% lubricant eye drops are considered as an auto-induction prodrug and natural ocular redox state balance therapies with implications in prevention and treatment of serious eye diseases that involve pathways of continuous oxidative damage to ocular tissues(cataracts, primary open-angle glaucoma, age-related macular degeneration) and sight-threatening glycosylation processes (diabetic retinopathy and consequent visual impairment) important for public health. The results of the study document that the therapeutic benefit in clinical trials is associated with the bioactivation universal antioxidant and transglycating properties of N-acetylcarnosine acting as the ophthalmic prodrug of L-carnosine, and depends on the nature of the specific drug delivery lubricant eye-drop formulation applied as the topical solution. The research highlights findings in N-acetylcarnosine prodrug activation, transport mechanisms, drug-to-drug interactions, and formulations in order to unlock the optimization of complicated ocular pharmacology of N-acetylcarnosine. Patented N-acetylcarnosine lubricant eye-drop formula was marketed as numerous human biological brands reaching important distribution networks on over 550 000 bottles sold. Nature Does Nothing Uselessly. -Aristotle Copyright © 2011 John Wiley & Sons, Ltd.

Changing Ecological and Cultural States and Preferences of Nature Conservation Policy: The Case of Nature Values Trade in South-Western Finland

ERIC Educational Resources Information Center

Paloniemi, Riikka; Vilja, Varho

2009-01-01

We present a rural Finnish case of nature conservation called the nature values trade (NVT) as an example of the process of changing ecological and cultural states and preferences of environmental policy. We emphasise the importance of local ecological and cultural circumstances for the formulation of environmental policy. The study shows how…

Measurement of Electromagnetic Energy Flow Through a Sparse Particulate Medium: A Perspective

NASA Technical Reports Server (NTRS)

Mishchenko, Michael I.

2013-01-01

First-principle analysis of the functional design of a well-collimated radiometer (WCR) reveals that in general, this instrument does not record the instantaneous directional flow of electromagnetic energy. Only in special cases can a sequence of measurements with a WCR yield the magnitude and direction of the local time-averaged Poynting vector. Our analysis demonstrates that it is imperative to clearly formulate the physical nature of the actual measurement afforded by a directional radiometer rather than presume desirable measurement capabilities. Only then can the directional radiometer be considered a legitimate part of physically based remote sensing and radiation-budget applications. We also emphasize the need for a better understanding of the nature of measurements with panoramic radiometers.

Graphene Oxide: An All-in-One Processing Additive for 3D Printing.

PubMed

García-Tuñón, Esther; Feilden, Ezra; Zheng, Han; D'Elia, Eleonora; Leong, Alan; Saiz, Eduardo

2017-09-27

Many 3D printing technologies are based on the development of inks and pastes to build objects through droplet or filament deposition (the latter also known as continuous extrusion, robocasting, or direct ink writing). Controlling and tuning rheological behavior is key for successful manufacturing using these techniques. Different formulations have been proposed, but the search continues for approaches that are clean, flexible, robust and that can be adapted to a wide range of materials. Here, we show how graphene oxide (GO) enables the formulation of water-based pastes to print a wide variety of materials (polymers, ceramics, and steel) using robocasting. This work combines flow and oscillatory rheology to provide further insights into the rheological behavior of suspensions combining GO with other materials. Graphene oxide can be used to manipulate the viscoelastic response, enabling the formulation of pastes with excellent printing behavior that combine shear thinning flow and a fast recovery of their elastic properties. These inks do not contain other additives, only GO and the material of interest. As a proof of concept, we demonstrate the 3D printing of additive-free graphene oxide structures as well as polymers, ceramics, and steel. Due to its amphiphilic nature and 2D structure, graphene oxide plays multiple roles, behaving as a dispersant, viscosifier, and binder. It stabilizes suspensions of different powders, modifies the flow and viscoelasticity of materials with different chemistries, particle sizes and shapes, and binds the particles together, providing green strength for manual handling. This approach enables printing complex 3D ceramic structures using robocasting with similar properties to alternative formulations, thus demonstrating the potential of using 2D colloids in materials manufacturing.

Beyond Yellow Curry: Assessing Commercial Curcumin Absorption Technologies.

PubMed

Douglass, Brad J; Clouatre, Dallas L

2015-01-01

Few natural products have demonstrated the range of protective and therapeutic promise as have turmeric and its principal bioactive components: curcumin, demethoxycurcumin, and bisdemethoxycurcumin. Success in translating this potential into tangible benefits has been limited by inherently poor intestinal absorption, rapid metabolism, and limited systemic bioavailability. Seeking to overcome these limitations, food ingredient formulators have begun to employ a variety of approaches to enhance absorption and bioactivity. Many of these strategies improve upon the age-old practice of consuming turmeric in fat-based sauces, such as in a fat-rich yellow curry. However, there exists uncertainty as to how the various commercially available offerings compare to each other in terms of either uptake or efficacy, and this uncertainty leaves physicians and nutritionists with a dearth of data for making recommendations to interested patients and consumers. Further complicating the issue are recent data suggesting that formulation strategies may not equally enhance the absorption of individual curcuminoids, a significant issue in that these curcuminoids exhibit somewhat different physiologic properties. This review introduces needed order to the curcumin marketplace by examining bioavailability studies on a number of commercial curcumin ingredients and evaluating them on a level playing field. The comparative analysis includes standard pharmacokinetic parameters and a new metric, relative mass efficiency (E). Relative mass efficiency allows for the comparison of different formulations even in cases in which the weight percentage of curcuminoids is vastly different. A hydrophilic carrier dispersed curcuminoid formula exhibits 45.9 times the bioavailability of the standard purified 95 percent curcuminoid preparation and, based on relative mass efficiency, 1.5 times the bioavailability of the next best commercial ingredient, a cyclodextrin complex. Delivery strategies can significantly improve the bioavailability of curcuminoids. Total formula mass is important for making practical formulation decisions about dosing, cost and space.

Improving the oral bioavailability of curcumin using novel organogel-based nanoemulsions.

PubMed

Yu, Hailong; Huang, Qingrong

2012-05-30

Curcumin is a natural bioactive compound with many health-promoting benefits. Its low oral bioavailability limits its application in functional foods. In the present study, novel organogel-based nanoemulsions have been developed for oral delivery of curcumin and improvement of its bioavailability. Recently developed curcumin organogel was used as the oil phase in the curcumin nanoemulsion formulation. Tween 20 was selected as the emulsifier on the basis of maximum in vitro bioaccessibility of curcumin in the nanoemulsion. In vitro lipolysis profile revealed that the digestion of nanoemulsion was significantly faster and more complete than the organogel. Permeation experiments on Caco-2 cell monolayers suggested that digestion-diffusion was the major absorption mechanism for curcumin in the nanoemulsion. Furthermore, in vivo pharmacokinetics analysis on mice confirmed that the oral bioavailability of curcumin in the nanoemulsion was increased by 9-fold compared with unformulated curcumin. This novel formulation approach may also be used for oral delivery of other poorly soluble nutraceuticals with high loading capacity, which has significant impact in functional foods, dietary supplements and pharmaceutical industries.

Effect of a labile methyl donor on the transformation of 5-demethyltangeretin and the related implication on bioactivity.

PubMed

Ting, Yuwen; Li, Colin C; Pan, Min-Hsiung; Ho, Chi-Tang; Huang, Qingrong

2013-08-28

Polymethoxyflavones (PMFs) belong to a subgroup of flavonoids that particularly exist in the peels of citrus fruits. Despite their many health-beneficial biofunctionalities, the lipophilic nature of PMFs limits their water solubility and oral bioavailability. To investigate the effect of the delivery system on the improvement of PMF bioavailibility, a lecithin-based emulsion was formulated for the delivery of two PMF compounds, tangeretin and 5-demethyltangeretin. While the emulsion system improved the digestion kinetics and the total solubilized PMF concentrations in in vitro lipolysis studies, the concentration of 5-demethyltangeretin decreased due to chemical transformation to its permethoxylated counterpart, tangeretin. The emulsifier lecithin used in this emulsion formulation contained a choline headgroup as a labile methyl group donor. The presence of a methyl donor potentially caused the transformation of 5-demethyltangeretin and reduced its anti-cancer-cell-proliferation activities. Moreover, this is the first report in the literature of the transformation from 5-demethyltangeretin to tangeretin in a lecithin-based emulsion during lipolysis, and the mechanism underlying this phenomenon has also been proposed for the first time.

Physical Stability Studies of Semi-Solid Formulations from Natural Compounds Loaded with Chitosan Microspheres

PubMed Central

Acosta, Niuris; Sánchez, Elisa; Calderón, Laura; Cordoba-Diaz, Manuel; Cordoba-Diaz, Damián; Dom, Senne; Heras, Ángeles

2015-01-01

A chitosan-based hydrophilic system containing an olive leaf extract was designed and its antioxidant capacity was evaluated. Encapsulation of olive leaf extract in chitosan microspheres was carried out by a spray-drying process. The particles obtained with this technique were found to be spherical and had a positive surface charge, which is an indicator of mucoadhesiveness. FTIR and X-ray diffraction results showed that there are not specific interactions of polyphenolic compounds in olive leaf extract with the chitosan matrix. Stability and release studies of chitosan microspheres loaded with olive leaf extract before and after the incorporation into a moisturizer base were performed. The resulting data showed that the developed formulations were stable up to three months. The encapsulation efficiency was around 44% and the release properties of polyphenols from the microspheres were found to be pH dependent. At pH 7.4, polyphenols release was complete after 6 h; whereas the amount of polyphenols released was 40% after the same time at pH 5.5. PMID:26389926

A computer code for multiphase all-speed transient flows in complex geometries. MAST version 1.0

NASA Technical Reports Server (NTRS)

Chen, C. P.; Jiang, Y.; Kim, Y. M.; Shang, H. M.

1991-01-01

The operation of the MAST code, which computes transient solutions to the multiphase flow equations applicable to all-speed flows, is described. Two-phase flows are formulated based on the Eulerian-Lagrange scheme in which the continuous phase is described by the Navier-Stokes equation (or Reynolds equations for turbulent flows). Dispersed phase is formulated by a Lagrangian tracking scheme. The numerical solution algorithms utilized for fluid flows is a newly developed pressure-implicit algorithm based on the operator-splitting technique in generalized nonorthogonal coordinates. This operator split allows separate operation on each of the variable fields to handle pressure-velocity coupling. The obtained pressure correction equation has the hyperbolic nature and is effective for Mach numbers ranging from the incompressible limit to supersonic flow regimes. The present code adopts a nonstaggered grid arrangement; thus, the velocity components and other dependent variables are collocated at the same grid. A sequence of benchmark-quality problems, including incompressible, subsonic, transonic, supersonic, gas-droplet two-phase flows, as well as spray-combustion problems, were performed to demonstrate the robustness and accuracy of the present code.

Effects of Ohmic Resistance on Dynamic Characteristics and Impedance of Micro/Nano Cantilever Beam resonators

NASA Astrophysics Data System (ADS)

Rezazadeh, Ghader; Keyvani, Aliasghar; Sadeghi, Morteza H.; Bahrami, Manouchehr

2013-06-01

Effects of Ohmic resistance on MEMS/NEMS vibrating structures that have always been dismissed in some situations may cause important changes in resonance properties and impedance parameters of the MEMS/NEMS based circuits. In this paper it is aimed to present a theoretical model to precisely investigate the problem on a simple cantilever-substrate resonator. In this favor the Ohm's current law and charge conservation law have been merged to find a differential Equation for voltage propagation on the beam and because mostly nano structures are expected as the scope of the problem, modified couple stress theory is used to formulate the dynamic motion of the beam. The two governing equations were coupled and both nonlinear that have been solved simultaneously using a Galerkin based state space formulation. The obtained results that are in exact agreement with previous works show that dynamic pull-in voltage, switching time, and impedance of structure as a MEMS capacitor especially in frequencies higher than natural resonance frequency strongly relay on electrical resistance of the beam and substrate material.

Aeroelastic Stability of Rotor Blades Using Finite Element Analysis

NASA Technical Reports Server (NTRS)

Chopra, I.; Sivaneri, N.

1982-01-01

The flutter stability of flap bending, lead-lag bending, and torsion of helicopter rotor blades in hover is investigated using a finite element formulation based on Hamilton's principle. The blade is divided into a number of finite elements. Quasi-steady strip theory is used to evaluate the aerodynamic loads. The nonlinear equations of motion are solved for steady-state blade deflections through an iterative procedure. The equations of motion are linearized assuming blade motion to be a small perturbation about the steady deflected shape. The normal mode method based on the coupled rotating natural modes is used to reduce the number of equations in the flutter analysis. First the formulation is applied to single-load-path blades (articulated and hingeless blades). Numerical results show very good agreement with existing results obtained using the modal approach. The second part of the application concerns multiple-load-path blades, i.e. bearingless blades. Numerical results are presented for several analytical models of the bearingless blade. Results are also obtained using an equivalent beam approach wherein a bearingless blade is modelled as a single beam with equivalent properties. Results show the equivalent beam model.

Robustness-Based Design Optimization Under Data Uncertainty

NASA Technical Reports Server (NTRS)

Zaman, Kais; McDonald, Mark; Mahadevan, Sankaran; Green, Lawrence

2010-01-01

This paper proposes formulations and algorithms for design optimization under both aleatory (i.e., natural or physical variability) and epistemic uncertainty (i.e., imprecise probabilistic information), from the perspective of system robustness. The proposed formulations deal with epistemic uncertainty arising from both sparse and interval data without any assumption about the probability distributions of the random variables. A decoupled approach is proposed in this paper to un-nest the robustness-based design from the analysis of non-design epistemic variables to achieve computational efficiency. The proposed methods are illustrated for the upper stage design problem of a two-stage-to-orbit (TSTO) vehicle, where the information on the random design inputs are only available as sparse point and/or interval data. As collecting more data reduces uncertainty but increases cost, the effect of sample size on the optimality and robustness of the solution is also studied. A method is developed to determine the optimal sample size for sparse point data that leads to the solutions of the design problem that are least sensitive to variations in the input random variables.

Efficacy and toxicological studies of cremophor EL free alternative paclitaxel formulation.

PubMed

Utreja, Puneet; Jain, Subheet; Yadav, Subodh; Khandhuja, K L; Tiwary, A K

2011-11-01

In the present study, Cremophor EL free paclitaxel elastic liposomal formulation consisting of soya phosphatidylcholine and biosurfactant sodium deoxycholate was developed and optimized. The toxicological profile, antitumor efficacy and hemolytic toxicity of paclitaxel elastic liposomal formulation in comparison to Cremophor EL based marketed formulation were evaluated. Paclitaxel elastic liposomal formulations were prepared and characterized in vitro, ex-vivo and in vivo. Single dose toxicity study of paclitaxel elastic liposomal and marketed formulation was carried out in dose range of 10, 20, 40, 80, 120, 160 and 200 mg/kg. Cytotoxicity of developed formulation was evaluated using small cell lung cancer cell line (A549). Antitumor activity of developed formulation was compared with the marketed formulation using Cytoselect™ 96-well cell transformation assay. In vivo administration of paclitaxel elastic liposomal formulation into mice showed 6 fold increase in Maximum Tolerated Dose (MTD) in comparison to the marketed formulation. Similarly, LD50 (141.6 mg/kg) was also found to increase significantly than the marketed formulation (16.7 mg/kg). Result of antitumor assay revealed a high reduction of tumor density with paclitaxel elastic liposomal formulation. Reduction in hemolytic toxicity was also observed with paclitaxel elastic liposomal formulation in comparison to the marketed formulation. The carrier based approach for paclitaxel delivery demonstrated significant reduction in toxicity as compared to the Cremophor EL based marketed formulation following intra-peritoneal administration in mice model. The reduced toxicity and enhanced anti-cancer activity of elastic liposomal formulation strongly indicate its potential for safe and effective delivery of paclitaxel.

Morphodynamic Modeling of the Lower Yellow River, China: Flux (Equilibrium) Form or Entrainment (Nonequilibrium) Form of Sediment Mass Conservation?

NASA Astrophysics Data System (ADS)

An, C.; Parker, G.; Ma, H.; Naito, K.; Moodie, A. J.; Fu, X.

2017-12-01

Models of river morphodynamics consist of three elements: (1) a treatment of flow hydraulics, (2) a formulation relating some aspect of sediment transport to flow hydraulics, and (3) a description of sediment conservation. In the case of unidirectional river flow, the Exner equation of sediment conservation is commonly described in terms of a flux-based formulation, in which bed elevation variation is related to the streamwise gradient of sediment transport rate. An alternate formulation of the Exner equation, however, is the entrainment-based formulation in which bed elevation variation is related to the difference between the entrainment rate of bed sediment into suspension and the deposition rate of suspended sediment onto the bed. In the flux-based formulation, sediment transport is regarded to be in a local equilibrium state (i.e., sediment transport rate locally equals sediment transport capacity). However, the entrainment-based formulation does not require this constraint; the sediment transport rate may lag in space and time behind the changing flow conditions. In modeling the fine-grained Lower Yellow River, it is usual to treat sediment conservation in terms of an entrainment-based (nonequilibrium) rather than a flux-based (equilibrium) formulation with the consideration that fine-grained sediment may be entrained at one place but deposited only at some distant location downstream. However, the differences in prediction between the two formulations are still not well known, and the entrainment formulation may not always be necessary for the Lower Yellow River. Here we study this problem by comparing the results of flux-based and entrainment-based morphodynamics under conditions typical of the Yellow River, using sediment transport equations specifically designed for the Lower Yellow River. We find, somewhat unexpectedly, that in a treatment of a 200-km reach using uniform sediment, there is little difference between the two formulations unless the sediment fall velocity is arbitrarily greatly reduced. A consideration of sediment mixtures, however, shows that the two formulations give very different patterns of grain sorting. We explain this in terms of the structures of the two Exner equations for sediment mixtures, and define conditions for applicability of each formulation.

Infant Skin Care Products: What Are the Issues?

PubMed

Kuller, Joanne McManus

2016-10-01

Infant skin is susceptible to dryness and irritation from external factors, including topical skin care products not formulated for the infant's skin. This may increase the risk of contact dermatitis. Parents frequently express concern regarding potential harm from ingredients in skin care products and seek information. This is complicated by several skin care myths. The purpose of this literature review was to provide evidence-based information to educate parents on the use of products for preterm and term infants. Multiple searches using PubMed were conducted including the search terms "infant skin care," "infant products," "infant bath," "emollients," "diaper skin care," and "diaper wipes." Reference lists of comprehensive reviews were also scanned. Google searches were used to assess consumer information, product information, and regulatory guidelines. There is little scientific evidence to support safety of natural/organic products on infant skin. Raw materials originate from different sources, complicating testing and comparisons of ingredients. Research shows that cleansers formulated for infant skin do not weaken the skin barrier the way harsher soaps and detergents can. Oils with the lowest oleic acid content provide a lower risk of irritant contact dermatitis. Nurses must be informed about natural and organic products, preservatives, and fragrances and know the definition of commonly used marketing terms. Decisions regarding the use of infant products in preterm and term infants should be evidence based. More research is needed to support claims regarding the safety of products used on infant skin.

Optimization of natural lipstick formulation based on pitaya (Hylocereus polyrhizus) seed oil using D-optimal mixture experimental design.

PubMed

Kamairudin, Norsuhaili; Gani, Siti Salwa Abd; Masoumi, Hamid Reza Fard; Hashim, Puziah

2014-10-16

The D-optimal mixture experimental design was employed to optimize the melting point of natural lipstick based on pitaya (Hylocereus polyrhizus) seed oil. The influence of the main lipstick components-pitaya seed oil (10%-25% w/w), virgin coconut oil (25%-45% w/w), beeswax (5%-25% w/w), candelilla wax (1%-5% w/w) and carnauba wax (1%-5% w/w)-were investigated with respect to the melting point properties of the lipstick formulation. The D-optimal mixture experimental design was applied to optimize the properties of lipstick by focusing on the melting point with respect to the above influencing components. The D-optimal mixture design analysis showed that the variation in the response (melting point) could be depicted as a quadratic function of the main components of the lipstick. The best combination of each significant factor determined by the D-optimal mixture design was established to be pitaya seed oil (25% w/w), virgin coconut oil (37% w/w), beeswax (17% w/w), candelilla wax (2% w/w) and carnauba wax (2% w/w). With respect to these factors, the 46.0 °C melting point property was observed experimentally, similar to the theoretical prediction of 46.5 °C. Carnauba wax is the most influential factor on this response (melting point) with its function being with respect to heat endurance. The quadratic polynomial model sufficiently fit the experimental data.

Potentiality of botanical agents for the management of post harvest insects of maize: a review.

PubMed

Soujanya, P Lakshmi; Sekhar, J C; Kumar, P; Sunil, N; Prasad, Ch Vara; Mallavadhani, U V

2016-05-01

Natural products derived from plants are emerging as potent biorational alternatives to synthetic insecticides for the integrated management of post harvest insects of maize. In this paper, effectiveness of botanicals including plant extracts, essential oils, their isolated pure compounds, plant based nano formulations and their mode of action against storage insects have been reviewed with special reference to maize. Plant based insecticides found to be the most promising means of controlling storage insects of maize in an eco friendly and sustainable manner. This article also throws light on the commercialization of botanicals, their limitations, challenges and future trends of storage insect management.

Consensus analysis of sastric formulations used by non-institutionally trained siddha medical practitioners of Virudhunagar and Tirunelveli districts of Tamil Nadu, India.

PubMed

Mutheeswaran, S; Pandikumar, P; Chellappandian, M; Ignacimuthu, S; Duraipandiyan, V; Logamanian, M

2014-04-11

Siddha system of traditional medicine has been practiced in Tamil Nadu. This system of medicine has a high number of non-institutionally trained practitioners but studies on their traditional medicinal knowledge are not adequate. The present study is aimed to document and analyze the sastric (traditional) formulations used by the non-institutionally trained siddha medical practitioners in Virudhunagar and Tirunelveli districts of Tamil Nadu, India. After obtaining prior informed consent, interviews were conducted with 115 non-institutionally trained siddha medical practitioners about the sastric formulations used by them for the treatment. Successive free listing method was adopted to collect the data and the data were analyzed by calculating Informant Consensus Factor (Fic) and Informant Agreement Ratio (IAR). The study documented data regarding 194 sastric formulations and they were classified into plant, mineral and animal based formulations. Quantitative analysis showed that 62.5% of the formulations were plant based, while the mineral based formulations had a high mean number of citations and versatile uses. Gastrointestinal (12.0%), kapha (11.3%) and dermatological (10.8%) ailments had a high percentage of citations. Jaundice had a high Fic value (0.750) followed by the dermatological ailments. The illness categories with high Fic values under each type of formulation were as follows: jaundice, aphrodisiac and urinary ailments (plant based); jaundice, cuts & wounds and dermatological ailments (mineral based); and hemorrhoids, kapha ailments and heart ailments (animal based formulations). The scientific studies conducted with important formulations under each illness category are discussed. The present study indicated the importance of some illnesses over the others and inclusion of new illnesses under each formulation. The ingredients used to prepare these formulations have shown varying degrees of scientific evidence; generally limited studies were available on the efficacy of them as formulations. Further in-depth studies on the formulations with high IAR value and Fic value of illness categories will be helpful to improve health status of the people. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Complete active space configuration interaction from state-averaged configuration interaction singles natural orbitals: Analytic first derivatives and derivative coupling vectors

NASA Astrophysics Data System (ADS)

Fales, B. Scott; Shu, Yinan; Levine, Benjamin G.; Hohenstein, Edward G.

2017-09-01

A new complete active space configuration interaction (CASCI) method was recently introduced that uses state-averaged natural orbitals from the configuration interaction singles method (configuration interaction singles natural orbital CASCI, CISNO-CASCI). This method has been shown to perform as well or better than state-averaged complete active space self-consistent field for a variety of systems. However, further development and testing of this method have been limited by the lack of available analytic first derivatives of the CISNO-CASCI energy as well as the derivative coupling between electronic states. In the present work, we present a Lagrangian-based formulation of these derivatives as well as a highly efficient implementation of the resulting equations accelerated with graphical processing units. We demonstrate that the CISNO-CASCI method is practical for dynamical simulations of photochemical processes in molecular systems containing hundreds of atoms.

Complete active space configuration interaction from state-averaged configuration interaction singles natural orbitals: Analytic first derivatives and derivative coupling vectors.

PubMed

Fales, B Scott; Shu, Yinan; Levine, Benjamin G; Hohenstein, Edward G

2017-09-07

A new complete active space configuration interaction (CASCI) method was recently introduced that uses state-averaged natural orbitals from the configuration interaction singles method (configuration interaction singles natural orbital CASCI, CISNO-CASCI). This method has been shown to perform as well or better than state-averaged complete active space self-consistent field for a variety of systems. However, further development and testing of this method have been limited by the lack of available analytic first derivatives of the CISNO-CASCI energy as well as the derivative coupling between electronic states. In the present work, we present a Lagrangian-based formulation of these derivatives as well as a highly efficient implementation of the resulting equations accelerated with graphical processing units. We demonstrate that the CISNO-CASCI method is practical for dynamical simulations of photochemical processes in molecular systems containing hundreds of atoms.

"A La Recherche Du" Quality of Life

ERIC Educational Resources Information Center

Jordan, Thomas E.

2011-01-01

This essay examines the stages of inquiry when we seek to formulate quality of life in an era before our own. There arises the question of the extent to which today's formulation of quality of life can be applied to an era far removed from our own. Implicitly, there is the nature of the time interval, T[subscript 1]...T[subscript n], and the…

A novel nanoscale-dispersed eye ointment for the treatment of dry eye disease

NASA Astrophysics Data System (ADS)

Zhang, Wenjian; Wang, Yan; Lee, Benjamin Tak Kwong; Liu, Chang; Wei, Gang; Lu, Weiyue

2014-03-01

A novel nanoscale-dispersed eye ointment (NDEO) for the treatment of severe evaporative dry eye has been successfully developed. The excipients used as semisolid lipids were petrolatum and lanolin, as used in conventional eye ointment, which were coupled with medium-chain triglycerides (MCT) as a liquid lipid; both phases were then dispersed in polyvinyl pyrrolidone solution to form a nanodispersion. Single-factor experiments were conducted to optimize the formulations. A transmission electron micrograph showed that the ointment matrix was entrapped in the nanoemulsion of MCT, with a mean particle size of about 100 nm. The optimized formulation of NDEO was stable when stored for six months at 4 °C, and demonstrated no cytotoxicity to human corneal epithelial cells when compared with commercial polymer-based artificial tears (Tears Natural® Forte). The therapeutic effects of NDEO were evaluated on a mouse model with ‘dry eye’. Both the tear break-up time and fluorescein staining demonstrated therapeutic improvement, displaying a trend of positive correlation with higher concentrations of ointment matrix in the NDEO formulations compared to a marketed product. Histological evaluation demonstrated that the NDEO restored the normal corneal and conjunctival morphology and is safe for ophthalmic application.

Fuzzy Logic-based expert system for evaluating cake quality of freeze-dried formulations.

PubMed

Trnka, Hjalte; Wu, Jian X; Van De Weert, Marco; Grohganz, Holger; Rantanen, Jukka

2013-12-01

Freeze-drying of peptide and protein-based pharmaceuticals is an increasingly important field of research. The diverse nature of these compounds, limited understanding of excipient functionality, and difficult-to-analyze quality attributes together with the increasing importance of the biosimilarity concept complicate the development phase of safe and cost-effective drug products. To streamline the development phase and to make high-throughput formulation screening possible, efficient solutions for analyzing critical quality attributes such as cake quality with minimal material consumption are needed. The aim of this study was to develop a fuzzy logic system based on image analysis (IA) for analyzing cake quality. Freeze-dried samples with different visual quality attributes were prepared in well plates. Imaging solutions together with image analytical routines were developed for extracting critical visual features such as the degree of cake collapse, glassiness, and color uniformity. On the basis of the IA outputs, a fuzzy logic system for analysis of these freeze-dried cakes was constructed. After this development phase, the system was tested with a new screening well plate. The developed fuzzy logic-based system was found to give comparable quality scores with visual evaluation, making high-throughput classification of cake quality possible. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association.

The type and composition of alginate and hyaluronic-based hydrogels influence the viability of stem cells of the apical papilla.

PubMed

Lambricht, Laure; De Berdt, Pauline; Vanacker, Julie; Leprince, Julian; Diogenes, Anibal; Goldansaz, Hadi; Bouzin, Caroline; Préat, Véronique; Dupont-Gillain, Christine; des Rieux, Anne

2014-12-01

The goal of the present work was to evaluate in vitro and in vivo the influence of various types and compositions of natural hydrogels on the viability and metabolic activity of SCAPs. Two alginate, three hyaluronic-based (Corgel™) hydrogel formulations and Matrigel were characterized for their mechanical, surface and microstructure properties using rheology, X-ray photoelectron spectroscopy and scanning electron microscopy, respectively. A characterized SCAP cell line (RP89 cells) was encapsulated in the different experimental hydrogel formulations. Cells were cultured in vitro, or implanted in cyclosporine treated mice. In vitro cell viability was evaluated using a Live/Dead assay and in vitro cellular metabolic activity was evaluated with a MTS assay. In vivo cell apoptosis was evaluated by a TUNEL test and RP89 cells were identified by human mitochondria immunostaining. Hydrogel composition influenced their mechanical and surface properties, and their microstructure. In vitro cell viability was above 80% after 2 days but decreased significantly after 7 days (60-40%). Viability at day 7 was the highest in Matrigel (70%) and then in Corgel 1.5 (60%). Metabolic activity increased over time in all the hydrogels, excepted in alginate SLM. SCAPs survived after 1 week in vivo with low apoptosis (<1%). The highest number of RP89 cells was found in Corgel 5.5 (140cells/mm(2)). Collectively, these data demonstrate that SCAP viability was directly modulated by hydrogel composition and suggest that a commercially available hyaluronic acid-based formulation might be a suitable delivery vehicle for SCAP-based dental pulp regeneration strategies. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Ionic-Liquid-Based Paclitaxel Preparation: A New Potential Formulation for Cancer Treatment.

PubMed

Chowdhury, Md Raihan; Moshikur, Rahman Md; Wakabayashi, Rie; Tahara, Yoshiro; Kamiya, Noriho; Moniruzzaman, Muhammad; Goto, Masahiro

2018-06-04

Paclitaxel (PTX) injection (i.e., Taxol) has been used as an effective chemotherapeutic treatment for various cancers. However, the current Taxol formulation contains Cremophor EL, which causes hypersensitivity reactions during intravenous administration and precipitation by aqueous dilution. This communication reports the preliminary results on the ionic liquid (IL)-based PTX formulations developed to address the aforementioned issues. The formulations were composed of PTX/cholinium amino acid ILs/ethanol/Tween-80/water. A significant enhancement in the solubility of PTX was observed with considerable correlation with the density and viscosity of the ILs, and with the side chain of the amino acids used as anions in the ILs. Moreover, the formulations were stable for up to 3 months. The driving force for the stability of the formulation was hypothesized to be the involvement of different types of interactions between the IL and PTX. In vitro cytotoxicity and antitumor activity of the IL-based formulations were evaluated on HeLa cells. The IL vehicles without PTX were found to be less cytotoxic than Taxol, while both the IL-based PTX formulation and Taxol exhibited similar antitumor activity. Finally, in vitro hypersensitivity reactions were evaluated on THP-1 cells and found to be significantly lower with the IL-based formulation than Taxol. This study demonstrated that specially designed ILs could provide a potentially safer alternative to Cremophor EL as an effective PTX formulation for cancer treatment giving fewer hypersensitivity reactions.

Scientific Inquiry: A Model for Online Searching.

ERIC Educational Resources Information Center

Harter, Stephen P.

1984-01-01

Explores scientific inquiry as philosophical and behavioral model for online search specialist and information retrieval process. Nature of scientific research is described and online analogs to research concepts of variable, hypothesis formulation and testing, operational definition, validity, reliability, assumption, and cyclical nature of…

Climbing Mount Probable

ERIC Educational Resources Information Center

Harper, Marc Allen

2009-01-01

This work attempts to explain the relationships between natural selection, information theory, and statistical inference. In particular, a geometric formulation of information theory known as information geometry and its deep connections to evolutionary game theory inform the role of natural selection in evolutionary processes. The goals of this…

Oligosaccharide-based Surfactant/Citric Acid Buffer System Stabilizes Lactate Dehydrogenase during Freeze-drying and Storage without the Addition of Natural Sugar.

PubMed

Ogawa, Shigesaburo; Kawai, Ryuichiro; Koga, Maito; Asakura, Kouichi; Takahashi, Isao; Osanai, Shuichi

2016-06-01

Experiments were conducted to assess the maintenance effects of oligosaccharide-based surfactants on the enzymatic activity of a model protein, lactate dehydrogenase (LDH), during freeze-drying and room temperature storage using the citric acid buffer system. Oligosaccharide-based surfactants, which exhibit a high glass transition temperature (Tg), promoted the eminent retention of enzymatic activity during these protocols, whereas monosaccharide-based surfactants with a low Tg displayed poor performance at high concentration, albeit much better than that of Tween 80 at middle concentration. The increase in the alkyl chain length did not exert positive effects as observed for the maintenance effect during freeze-thawing, but an amphiphilic nature and a glass forming ability were crucial for the effective stabilization at a low excipient concentration during freeze-drying. Even a low oligosaccharide-based surfactant content (0.1 mg mL(-1)) could maintain LDH activity during freeze-drying, but a high surfactant content (1.0 mg mL(-1)) was required to prevent buffer precipitation and retain high LDH activity on storage. Regarding storage, glass formation restricted molecular mobility in the lyophilized matrix, and LDH activity was effectively retained. The present results describe a strategy based on the glass-forming ability of surfactant-type excipients that affords a natural sugar-free formulation or an alternative use for polysorbate-type surfactants.

A unified approach to fluid-flow, geomechanical, and seismic modelling

NASA Astrophysics Data System (ADS)

Yarushina, Viktoriya; Minakov, Alexander

2016-04-01

The perturbations of pore pressure can generate seismicity. This is supported by observations from human activities that involve fluid injection into rocks at high pressure (hydraulic fracturing, CO2 storage, geothermal energy production) and natural examples such as volcanic earthquakes. Although the seismic signals that emerge during geotechnical operations are small both in amplitude and duration when compared to natural counterparts. A possible explanation for the earthquake source mechanism is based on a number of in situ stress measurements suggesting that the crustal rocks are close to its plastic yield limit. Hence, a rapid increase of the pore pressure decreases the effective normal stress, and, thus, can trigger seismic shear deformation. At the same time, little attention has been paid to the fact that the perturbation of fluid pressure itself represents an acoustic source. Moreover, non-double-couple source mechanisms are frequently reported from the analysis of microseismicity. A consistent formulation of the source mechanism describing microseismic events should include both a shear and isotropic component. Thus, improved understanding of the interaction between fluid flow and seismic deformation is needed. With this study we aim to increase the competence in integrating real-time microseismic monitoring with geomechanical modelling such that there is a feedback loop between monitored deformation and stress field modelling. We propose fully integrated seismic, geomechanical and reservoir modelling. Our mathematical formulation is based on fundamental set of force balance, mass balance, and constitutive poro-elastoplastic equations for two-phase media consisting of deformable solid rock frame and viscous fluid. We consider a simplified 1D modelling setup for consistent acoustic source and wave propagation in poro-elastoplastic media. In this formulation the seismic wave is generated due to local changes of the stress field and pore pressure induced by e.g. fault generation or strain localization. This approach gives unified framework to characterize microseismicity of both class-I (pressure induced) and class-II (stress triggered) type of events. We consider two modelling setups. In the first setup the event is located within the reservoir and associated with pressure/stress drop due to fracture initiation. In the second setup we assume that seismic wave from a distant source hits a reservoir. The unified formulation of poro-elastoplastic deformation allows us to link the macroscopic stresses to local seismic instability.

Formulation and method for preparing gels comprising hydrous aluminum oxide

DOEpatents

Collins, Jack L.

2014-06-17

Formulations useful for preparing hydrous aluminum oxide gels contain a metal salt including aluminum, an organic base, and a complexing agent. Methods for preparing gels containing hydrous aluminum oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including aluminum, an organic base, and a complexing agent.

Formulation and method for preparing gels comprising hydrous cerium oxide

DOEpatents

Collins, Jack L; Chi, Anthony

2013-05-07

Formulations useful for preparing hydrous cerium oxide gels contain a metal salt including cerium, an organic base, and a complexing agent. Methods for preparing gels containing hydrous cerium oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including cerium, an organic base, and a complexing agent.

Scale up, optimization and stability analysis of Curcumin C3 complex-loaded nanoparticles for cancer therapy

PubMed Central

2012-01-01

Background Nanoparticle based delivery of anticancer drugs have been widely investigated. However, a very important process for Research & Development in any pharmaceutical industry is scaling nanoparticle formulation techniques so as to produce large batches for preclinical and clinical trials. This process is not only critical but also difficult as it involves various formulation parameters to be modulated all in the same process. Methods In our present study, we formulated curcumin loaded poly (lactic acid-co-glycolic acid) nanoparticles (PLGA-CURC). This improved the bioavailability of curcumin, a potent natural anticancer drug, making it suitable for cancer therapy. Post formulation, we optimized our process by Reponse Surface Methodology (RSM) using Central Composite Design (CCD) and scaled up the formulation process in four stages with final scale-up process yielding 5 g of curcumin loaded nanoparticles within the laboratory setup. The nanoparticles formed after scale-up process were characterized for particle size, drug loading and encapsulation efficiency, surface morphology, in vitro release kinetics and pharmacokinetics. Stability analysis and gamma sterilization were also carried out. Results Results revealed that that process scale-up is being mastered for elaboration to 5 g level. The mean nanoparticle size of the scaled up batch was found to be 158.5 ± 9.8 nm and the drug loading was determined to be 10.32 ± 1.4%. The in vitro release study illustrated a slow sustained release corresponding to 75% drug over a period of 10 days. The pharmacokinetic profile of PLGA-CURC in rats following i.v. administration showed two compartmental model with the area under the curve (AUC0-∞) being 6.139 mg/L h. Gamma sterilization showed no significant change in the particle size or drug loading of the nanoparticles. Stability analysis revealed long term physiochemical stability of the PLGA-CURC formulation. Conclusions A successful effort towards formulating, optimizing and scaling up PLGA-CURC by using Solid-Oil/Water emulsion technique was demonstrated. The process used CCD-RSM for optimization and further scaled up to produce 5 g of PLGA-CURC with almost similar physicochemical characteristics as that of the primary formulated batch. PMID:22937885

Scale up, optimization and stability analysis of Curcumin C3 complex-loaded nanoparticles for cancer therapy.

PubMed

Ranjan, Amalendu P; Mukerjee, Anindita; Helson, Lawrence; Vishwanatha, Jamboor K

2012-08-31

Nanoparticle based delivery of anticancer drugs have been widely investigated. However, a very important process for Research & Development in any pharmaceutical industry is scaling nanoparticle formulation techniques so as to produce large batches for preclinical and clinical trials. This process is not only critical but also difficult as it involves various formulation parameters to be modulated all in the same process. In our present study, we formulated curcumin loaded poly (lactic acid-co-glycolic acid) nanoparticles (PLGA-CURC). This improved the bioavailability of curcumin, a potent natural anticancer drug, making it suitable for cancer therapy. Post formulation, we optimized our process by Reponse Surface Methodology (RSM) using Central Composite Design (CCD) and scaled up the formulation process in four stages with final scale-up process yielding 5 g of curcumin loaded nanoparticles within the laboratory setup. The nanoparticles formed after scale-up process were characterized for particle size, drug loading and encapsulation efficiency, surface morphology, in vitro release kinetics and pharmacokinetics. Stability analysis and gamma sterilization were also carried out. Results revealed that that process scale-up is being mastered for elaboration to 5 g level. The mean nanoparticle size of the scaled up batch was found to be 158.5±9.8 nm and the drug loading was determined to be 10.32±1.4%. The in vitro release study illustrated a slow sustained release corresponding to 75% drug over a period of 10 days. The pharmacokinetic profile of PLGA-CURC in rats following i.v. administration showed two compartmental model with the area under the curve (AUC0-∞) being 6.139 mg/L h. Gamma sterilization showed no significant change in the particle size or drug loading of the nanoparticles. Stability analysis revealed long term physiochemical stability of the PLGA-CURC formulation. A successful effort towards formulating, optimizing and scaling up PLGA-CURC by using Solid-Oil/Water emulsion technique was demonstrated. The process used CCD-RSM for optimization and further scaled up to produce 5 g of PLGA-CURC with almost similar physicochemical characteristics as that of the primary formulated batch.

Coupled variational formulations of linear elasticity and the DPG methodology

NASA Astrophysics Data System (ADS)

Fuentes, Federico; Keith, Brendan; Demkowicz, Leszek; Le Tallec, Patrick

2017-11-01

This article presents a general approach akin to domain-decomposition methods to solve a single linear PDE, but where each subdomain of a partitioned domain is associated to a distinct variational formulation coming from a mutually well-posed family of broken variational formulations of the original PDE. It can be exploited to solve challenging problems in a variety of physical scenarios where stability or a particular mode of convergence is desired in a part of the domain. The linear elasticity equations are solved in this work, but the approach can be applied to other equations as well. The broken variational formulations, which are essentially extensions of more standard formulations, are characterized by the presence of mesh-dependent broken test spaces and interface trial variables at the boundaries of the elements of the mesh. This allows necessary information to be naturally transmitted between adjacent subdomains, resulting in coupled variational formulations which are then proved to be globally well-posed. They are solved numerically using the DPG methodology, which is especially crafted to produce stable discretizations of broken formulations. Finally, expected convergence rates are verified in two different and illustrative examples.

Treatment of Xerosis with a Topical Formulation Containing Glyceryl Glucoside, Natural Moisturizing Factors, and Ceramide

PubMed Central

Kausch, Martina; Rippke, Frank; Schoelermann, Andrea M.; Filbry, Alexander W.

2012-01-01

Objective: To assess the effects of Light Formulation, an oil-in-water emulsion, and Rich Formulation, a water-in-oil emulsion, for the treatment of xerosis. Design: Two double-blind, vehicle-controlled trials (both formulations); a double-blind, randomized regression study (Rich Formulation); and a single-blind tolerability study (Light Formulation). The two formulations were applied twice daily for two weeks, for five days in the regression study, and twice daily for two weeks in the tolerability study. Setting: Studies were conducted during winter in Hamburg, Germany. Participants: A total of 169 subjects were enrolled and 154 completed the studies. The majority were between 50 and 80 years of age, women, all with very dry skin. One withdrew because of an incompatibility reaction that reoccurred with the subject's own body lotion after sun exposure. Measurements: Skin hydration and skin barrier function with both formulations over two weeks, long-term moisturization effect after discontinuation of Rich Formulation, and symptom improvement and skin tolerability with Light Formulation. Results: Vehicle-controlled studies of Light and Rich Formulations demonstrated significantly improved hydration at Weeks 1 and 2 versus the untreated site and vehicles, and significantly reduced transepidermal water loss versus untreated site and basic vehicle. Both products significantly decreased visible dryness and tactile roughness. In the regression study, Rich Formulation maintained significant moisturization six days after treatment discontinuation. Light Formulation reduced symptoms of itching, burning, tightness, tingling, and feeling of dryness. Conclusion: These formulations represent a new approach for the treatment of xerosis by addressing multiple key deficiencies in skin hydration. PMID:22916312

Undefined cellulase formulations hinder scientific reproducibility

DOE PAGES

Himmel, Michael E.; Abbas, Charles A.; Baker, John O.; ...

2017-11-28

In the shadow of a burgeoning biomass-to-fuels industry, biological conversion of lignocellulose to fermentable sugars in a cost-effective manner is key to the success of second-generation and advanced biofuel production. For the effective comparison of one cellulase preparation to another, cellulase assays are typically carried out with one or more engineered cellulase formulations or natural exoproteomes of known performance serving as positive controls. When these formulations have unknown composition, as is the case with several widely used commercial products, it becomes impossible to compare or reproduce work done today to work done in the future, where, for example, such preparationsmore » may not be available. Therefore, being a critical tenet of science publishing, experimental reproducibility is endangered by the continued use of these undisclosed products. We propose the introduction of standard procedures and materials to produce specific and reproducible cellulase formulations. These formulations are to serve as yardsticks to measure improvements and performance of new cellulase formulations.« less

Undefined cellulase formulations hinder scientific reproducibility

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

Himmel, Michael E.; Abbas, Charles A.; Baker, John O.

In the shadow of a burgeoning biomass-to-fuels industry, biological conversion of lignocellulose to fermentable sugars in a cost-effective manner is key to the success of second-generation and advanced biofuel production. For the effective comparison of one cellulase preparation to another, cellulase assays are typically carried out with one or more engineered cellulase formulations or natural exoproteomes of known performance serving as positive controls. When these formulations have unknown composition, as is the case with several widely used commercial products, it becomes impossible to compare or reproduce work done today to work done in the future, where, for example, such preparationsmore » may not be available. Therefore, being a critical tenet of science publishing, experimental reproducibility is endangered by the continued use of these undisclosed products. We propose the introduction of standard procedures and materials to produce specific and reproducible cellulase formulations. These formulations are to serve as yardsticks to measure improvements and performance of new cellulase formulations.« less

Development and Assessment of Countermeasure Formulations for Treatment of Lung Injury Induced by Chlorine Inhalation

PubMed Central

Hoyle, Gary W.; Chen, Jing; Schlueter, Connie F.; Mo, Yiqun; Humphrey, David M.; Rawson, Greg; Niño, Joe A.; Carson, Kenneth H.

2016-01-01

Chlorine is a commonly used, reactive compound to which humans can be exposed via accidental or intentional release resulting in acute lung injury. Formulations of rolipram (a phosphodiesterase inhibitor), triptolide (a natural plant product with anti-inflammatory properties), and budesonide (a corticosteroid), either neat or in conjunction with poly(lactic:glycolic acid) (PLGA), were developed for treatment of chlorine-induced acute lung injury by intramuscular injection. Formulations were produced by spray-drying, which generated generally spherical microparticles that were suitable for intramuscular injection. Multiple parameters were varied to produce formulations with a wide range of in vitro release kinetics. Testing of selected formulations in chlorine-exposed mice demonstrated efficacy against key aspects of acute lung injury. The results show the feasibility of developing microencapsulated formulations that could be used to treat chlorine-induced acute lung injury by intramuscular injection, which represents a preferred route of administration in a mass casualty situation. PMID:26952014

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

Hoyle, Gary W., E-mail: Gary.Hoyle@louisville.edu; Chen, Jing; Schlueter, Connie F.

Chlorine is a commonly used, reactive compound to which humans can be exposed via accidental or intentional release resulting in acute lung injury. Formulations of rolipram (a phosphodiesterase inhibitor), triptolide (a natural plant product with anti-inflammatory properties), and budesonide (a corticosteroid), either neat or in conjunction with poly(lactic:glycolic acid) (PLGA), were developed for treatment of chlorine-induced acute lung injury by intramuscular injection. Formulations were produced by spray-drying, which generated generally spherical microparticles that were suitable for intramuscular injection. Multiple parameters were varied to produce formulations with a wide range of in vitro release kinetics. Testing of selected formulations in chlorine-exposedmore » mice demonstrated efficacy against key aspects of acute lung injury. The results show the feasibility of developing microencapsulated formulations that could be used to treat chlorine-induced acute lung injury by intramuscular injection, which represents a preferred route of administration in a mass casualty situation. - Highlights: • Chlorine causes lung injury when inhaled and is considered a chemical threat agent. • Countermeasures for treatment of chlorine-induced acute lung injury are needed. • Formulations containing rolipram, triptolide, or budesonide were produced. • Formulations with a wide range of release properties were developed. • Countermeasure formulations inhibited chlorine-induced lung injury in mice.« less

Locating an imaging radar in Canada for identifying spaceborne objects

NASA Astrophysics Data System (ADS)

Schick, William G.

1992-12-01

This research presents a study of the maximal coverage p-median facility location problem as applied to the location of an imaging radar in Canada for imaging spaceborne objects. The classical mathematical formulation of the maximal coverage p-median problem is converted into network-flow with side constraint formulations that are developed using a scaled down version of the imaging radar location problem. Two types of network-flow with side constraint formulations are developed: a network using side constraints that simulates the gains in a generalized network; and a network resembling a multi-commodity flow problem that uses side constraints to force flow along identical arcs. These small formulations are expanded to encompass a case study using 12 candidate radar sites, and 48 satellites divided into three states. SAS/OR PROC NETFLOW was used to solve the network-flow with side constraint formulations. The case study show that potential for both formulations, although the simulated gains formulation encountered singular matrix computational difficulties as a result of the very organized nature of its side constraint matrix. The multi-commodity flow formulation, when combined with equi-distribution of flow constraints, provided solutions for various values of p, the number of facilities to be selected.

Herbicidal activity of slow-release herbicide formulations in wheat stands infested by weeds.

PubMed

Zhila, Natalia; Murueva, Anastasiya; Shershneva, Anna; Shishatskaya, Ekaterina; Volova, Tatiana

2017-10-03

The present study reports the herbicidal activity of metribuzin and tribenuron-methyl embedded in the degradable matrix of natural poly-3-hydroxybutyrate [P(3HB)/MET and P(3HB)/TBM]. The developed formulations were constructed as films and microgranules, which were tested against the weeds such as white sweet clover Melilotus albus and lamb's quarters Chenopodium album in the presence of soft spring wheat (Triticum aestivum, cv. Altaiskaya 70) as the subject crop for investigation. The activity was measured in laboratory scale experiments by determining the density and weight of the vegetative organs of weeds. The study was also aimed at testing the effect of the experimental formulation on the growth of wheat crop as dependent on the method of herbicide delivery. The experimental MET and TBM formulations showed pronounced herbicidal activity against the weed species used in the study. The effectiveness of the experimental formulations in inhibiting weed growth was comparable to and, sometimes, higher than that of the commercial formulations (positive control). The amount of the biomass of the wheat treated with the experimental herbicide formulations was significantly greater than that of the wheat treated with commercial formulations.

Evaluation of indoxacarb and fipronil (s)-methoprene topical spot-on formulations to control flea populations in naturally infested dogs and cats in private residences in Tampa FL. USA

PubMed Central

2013-01-01

Background A study was conducted to evaluate and compare the effectiveness of two different spot-on topical flea products to control flea infestations on naturally infested dogs and cats in Tampa, FL USA. Methods Thirty-two dogs and 3 cats with natural flea infestations living in 18 homes were treated topically with a 19.53% w/w spot-on formulation of indoxacarb. Another thirty dogs and 2 cats living in 19 different homes were treated topically with either fipronil (9.8% w/w)/(s)-methoprene (8.89% w/w) or fipronil (9.8% w/w)/(s)-methoprene (11.8% w/w), respectively. All products were applied according to label directions by study investigators on day 0 and again between days 28 and 30. Flea populations on pets were assessed using visual area counts and premise flea infestations were assessed using intermittent-light flea traps on days 0, 7, 14, 21, 28–30, 40–45, and 54–60. Results A single application of the indoxacarb or fipronil (s)-methoprene formulations reduced flea populations on pets by 97.8% and 85.5%, respectively within 7 days. One month (28–30 days) after treatment the indoxacarb and fipronil (s)-methoprene formulations reduced on-animal flea burdens by 95.0% and 49.5%, respectively. Following two monthly applications of either the indoxacarb or fipronil (s)-methoprene formulations, pet flea burdens were reduced by 99.1% and 54.8%, respectively, by days 54 – 60. At the end of the two month study, 77.1% and 15.6% of the dogs and cats in the indoxacarb and fipronil (s)-methoprene treatment groups, respectively were flea free. Flea numbers in the indoor-premises were markedly reduced in both treatment groups by days 54–60, with 97.7% and 84.6% reductions in intermittent-light flea trap counts in the indoxacarb and fipronil (s)-methoprene treatment groups, respectively. Conclusions This in-home investigation conducted during the summer of 2013 in subtropical Tampa, FL, is the first published U.S field investigation of the indoxacarb topical formulation. The indoxacarb formulation was able to effectively control flea populations in heavily flea infested pets and homes. The efficacy achieved by the fipronil (s)-methoprene formulation against flea infestations on these pets was lower than in previous investigations using the same study design. PMID:24373508

Element free Galerkin formulation of composite beam with longitudinal slip

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

Ahmad, Dzulkarnain; Mokhtaram, Mokhtazul Haizad; Badli, Mohd Iqbal

2015-05-15

Behaviour between two materials in composite beam is assumed partially interact when longitudinal slip at its interfacial surfaces is considered. Commonly analysed by the mesh-based formulation, this study used meshless formulation known as Element Free Galerkin (EFG) method in the beam partial interaction analysis, numerically. As meshless formulation implies that the problem domain is discretised only by nodes, the EFG method is based on Moving Least Square (MLS) approach for shape functions formulation with its weak form is developed using variational method. The essential boundary conditions are enforced by Langrange multipliers. The proposed EFG formulation gives comparable results, after beenmore » verified by analytical solution, thus signify its application in partial interaction problems. Based on numerical test results, the Cubic Spline and Quartic Spline weight functions yield better accuracy for the EFG formulation, compares to other proposed weight functions.« less

Liquid Crystal Formation from Sunflower Oil: Long Term Stability Studies.

PubMed

da Rocha-Filho, Pedro Alves; Maruno, Mônica; Ferrari, Márcio; Topan, José Fernando

2016-06-09

The Brazilian biodiversity offers a multiplicity of raw materials with great potential in cosmetics industry applications. Some vegetable oils and fatty esters increase skin hydration by occlusivity, keeping the skin hydrated and with a shiny appearance. Sunflower (Helianthus annus L.) oil is widely employed in cosmetic emulsions in the form of soaps, creams, moisturizers and skin cleansers due to the presence of polyphenols and its high vitamin E content. Liquid crystals are systems with many applications in both pharmaceutical and cosmetic formulations and are easily detected by microscopy under polarized light due to their birefringence properties. The aim of this research was to develop emulsions from natural sunflower oil for topical uses. Sunflower oil (75.0% w/w) was combined with liquid vaseline (25.0% w/w) employing a natural self-emulsifying base (SEB) derivative. The high temperature of the emulsification process did not influence the antioxidant properties of sunflower oil. Fatty esters were added to cosmetic formulations and extended stability tests were performed to characterize the emulsions. Fatty esters like cetyl palmitate and cetyl ester increase the formation of anisotropic structures. O/W emulsions showed acidic pH values and pseudoplastic behavior. The presence of a lamellar phase was observed after a period of 90 days under different storage conditions.

Dirac structures in nonequilibrium thermodynamics

NASA Astrophysics Data System (ADS)

Gay-Balmaz, François; Yoshimura, Hiroaki

2018-01-01

Dirac structures are geometric objects that generalize both Poisson structures and presymplectic structures on manifolds. They naturally appear in the formulation of constrained mechanical systems. In this paper, we show that the evolution equations for nonequilibrium thermodynamics admit an intrinsic formulation in terms of Dirac structures, both on the Lagrangian and the Hamiltonian settings. In the absence of irreversible processes, these Dirac structures reduce to canonical Dirac structures associated with canonical symplectic forms on phase spaces. Our geometric formulation of nonequilibrium thermodynamic thus consistently extends the geometric formulation of mechanics, to which it reduces in the absence of irreversible processes. The Dirac structures are associated with the variational formulation of nonequilibrium thermodynamics developed in the work of Gay-Balmaz and Yoshimura, J. Geom. Phys. 111, 169-193 (2017a) and are induced from a nonlinear nonholonomic constraint given by the expression of the entropy production of the system.

Antimicrobial efficacy of a novel eucalyptus oil, chlorhexidine digluconate and isopropyl alcohol biocide formulation.

PubMed

Hendry, Emma; Conway, Barbara; Worthington, Tony

2012-10-30

Effective surface disinfection is a fundamental infection control strategy within healthcare. This study assessed the antimicrobial efficacy of novel biocide formulations comprising 5% and 2% eucalyptus oil (EO) combined with 2% chlorhexidine digluconate (CHG) and 70% isopropyl alcohol (IPA) contained within a wipe. The efficacy of this novel antimicrobial formulation to remove and eliminate methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli and Candida albicans from steel surfaces was investigated. Adpression studies of pre-contaminated wipes were also utilised to assess their potential to induce cross-contamination between hard surfaces. Furthermore, the bactericidal nature of the EO-formulation was established in addition to time-kill. The EO-containing formulations demonstrated bactericidal antimicrobial efficacy against all microorganisms and did not induce surface cross-contamination. There was no significant difference (p < 0.05) between the 5% and 2% EO formulations in their ability to remove microorganisms from steel surfaces, however both significantly (p < 0.05) removed more than the control formulations. Microbial biofilms were eliminated within 10 min (p < 0.05) when exposed to the EO formulations. Our novel EO-formulation demonstrated rapid antimicrobial efficacy for potential disinfection and elimination of microbial biofilms from hard surfaces and may therefore be a useful adjunct to current infection control strategies currently employed within healthcare facilities.

Antimicrobial Efficacy of a Novel Eucalyptus Oil, Chlorhexidine Digluconate and Isopropyl Alcohol Biocide Formulation

PubMed Central

Hendry, Emma; Conway, Barbara; Worthington, Tony

2012-01-01

Effective surface disinfection is a fundamental infection control strategy within healthcare. This study assessed the antimicrobial efficacy of novel biocide formulations comprising 5% and 2% eucalyptus oil (EO) combined with 2% chlorhexidine digluconate (CHG) and 70% isopropyl alcohol (IPA) contained within a wipe. The efficacy of this novel antimicrobial formulation to remove and eliminate methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli and Candida albicans from steel surfaces was investigated. Adpression studies of pre-contaminated wipes were also utilised to assess their potential to induce cross-contamination between hard surfaces. Furthermore, the bactericidal nature of the EO-formulation was established in addition to time-kill. The EO-containing formulations demonstrated bactericidal antimicrobial efficacy against all microorganisms and did not induce surface cross-contamination. There was no significant difference (p < 0.05) between the 5% and 2% EO formulations in their ability to remove microorganisms from steel surfaces, however both significantly (p < 0.05) removed more than the control formulations. Microbial biofilms were eliminated within 10 min (p < 0.05) when exposed to the EO formulations. Our novel EO-formulation demonstrated rapid antimicrobial efficacy for potential disinfection and elimination of microbial biofilms from hard surfaces and may therefore be a useful adjunct to current infection control strategies currently employed within healthcare facilities. PMID:23203047

Corrigendum to "Processes and time scales of magmatic evolution as revealed by Fe-Mg chemical and isotopic zoning in natural olivines" [Geochim. Cosmochim. Acta 154 (2015) 130-150

NASA Astrophysics Data System (ADS)

Oeser, Martin; Dohmen, Ralf; Horn, Ingo; Schuth, Stephan; Weyer, Stefan

2018-05-01

The authors regret that equations EA.4 and EA.5 in the Electronic Annex were incomplete. Please see the new, corrected version of the Electronic Annex for the complete formulations of these equations. Accordingly, the correct formulation of Eq. (2) on page 132 is as follows:

Piperine-pro-nanolipospheres as a novel oral delivery system of cannabinoids: Pharmacokinetic evaluation in healthy volunteers in comparison to buccal spray administration.

PubMed

Cherniakov, Irina; Izgelov, Dvora; Barasch, Dinorah; Davidson, Elyad; Domb, Abraham J; Hoffman, Amnon

2017-11-28

Nowadays, therapeutic indications for cannabinoids, specifically Δ 9 -tetrahydrocannabinol (THC) and Cannabidiol (CBD) are widening. However, the oral consumption of the molecules is very limited due to their highly lipophilic nature that leads to poor solubility at the aqueous environment. Additionally, THC and CBD are prone to extensive first pass mechanisms. These absorption obstacles render the molecules with low and variable oral bioavailability. To overcome these limitations we designed and developed the advanced pro-nanolipospheres (PNL) formulation. The PNL delivery system is comprised of a medium chain triglyceride, surfactants, a co-solvent and the unique addition of a natural absorption enhancer: piperine. Piperine was selected due to its distinctive inhibitory properties affecting both Phase I and Phase II metabolism. This constellation self emulsifies into nano particles that entrap the cannabinoids and the piperine in their core and thus improve their solubility while piperine and the other PNL excipients inhibit their intestinal metabolism. Another clear advantage of the formulation is that its composition of materials is approved for human consumption. The safe nature of the excipients enabled their direct evaluation in humans. In order to evaluate the pharmacokinetic profile of the THC-CBD-piperine-PNL formulation, a two-way crossover, single administration clinical study was conducted. The trial comprised of 9 healthy volunteers under fasted conditions. Each subject received a THC-CBD (10.8mg, 10mg respectively) piperine (20mg)-PNL filled capsule and an equivalent dose of the oromucosal spray Sativex® with a washout period in between treatments. Single oral administration of the piperine-PNL formulation resulted in a 3-fold increase in Cmax and a 1.5-fold increase in AUC for THC when compared to Sativex®. For CBD, a 4-fold increase in Cmax and a 2.2-fold increase in AUC was observed. These findings demonstrate the potential this formulation has in serving as a standardized oral cannabinoid formulation. Moreover, the concept of improving oral bioavailability described here, can pave the way for other potential lipophilic active compounds requiring enhancement of their oral bioavailability. Copyright © 2017 Elsevier B.V. All rights reserved.

Formulation and method for preparing gels comprising hydrous hafnium oxide

DOEpatents

Collins, Jack L; Hunt, Rodney D; Montgomery, Frederick C

2013-08-06

Formulations useful for preparing hydrous hafnium oxide gels contain a metal salt including hafnium, an acid, an organic base, and a complexing agent. Methods for preparing gels containing hydrous hafnium oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including hafnium, an acid, an organic base, and a complexing agent.

Triboelectric Charging in Simulated Mars Environment

NASA Technical Reports Server (NTRS)

Lee, R.; Barile, R.

1999-01-01

Triboelectric charging of nonconducting materials followed by sudden electrostatic discharge (ESD) can damage electronic equipment and become ignition hazard to combustible materials. Mars atmosphere has near zero humidity and therefore natural charge bleeding to surroundings is anticipated to be limited. Potential mitigation of ESD problems has been conjectured based upon strong extraterrestrial radiation on Mars compared to earth. A hypothesis was formulated that ESD problem is less significant in simulated Mars condition since strong radiation and presence of argon will generate an ionized environment; this will be conducive to rapid bleeding of static charge into the surroundings.

[Wilson's principles--a base of modern teratology].

PubMed

Burdan, Franciszek; Bełzek, Artur; Szumiło, Justyna; Dudka, Jarosław; Korobowicz, Agnieszka; Tokarska, Edyta; Klepacz, Lidia; Bełzek, Marta; Klepacz, Robert

2006-03-01

Wilson's principles were formulated after thalidomide tragedy. They become a fundamental for teratological studies with drugs and other factors that may disturb fetal development. It is postulated that susceptibility to teratogen depends on the genotype and developmental stage of the conceptus. Teratogenic agents act in specific manner on developing cells and tissues. The exposition depends on the agent's nature and availability. Manifestations of deviant development depends on the dosage and exposure frequency. In case of abnormal development the final manifestations include death of embryo or fetus, malformation, growth retardation and functional disorder.

Combined magnetic vector-scalar potential finite element computation of 3D magnetic field and performance of modified Lundell alternators in Space Station applications. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Wang, Ren H.

1991-01-01

A method of combined use of magnetic vector potential (MVP) based finite element (FE) formulations and magnetic scalar potential (MSP) based FE formulations for computation of three-dimensional (3D) magnetostatic fields is developed. This combined MVP-MSP 3D-FE method leads to considerable reduction by nearly a factor of 3 in the number of unknowns in comparison to the number of unknowns which must be computed in global MVP based FE solutions. This method allows one to incorporate portions of iron cores sandwiched in between coils (conductors) in current-carrying regions. Thus, it greatly simplifies the geometries of current carrying regions (in comparison with the exclusive MSP based methods) in electric machinery applications. A unique feature of this approach is that the global MSP solution is single valued in nature, that is, no branch cut is needed. This is again a superiority over the exclusive MSP based methods. A Newton-Raphson procedure with a concept of an adaptive relaxation factor was developed and successfully used in solving the 3D-FE problem with magnetic material anisotropy and nonlinearity. Accordingly, this combined MVP-MSP 3D-FE method is most suited for solution of large scale global type magnetic field computations in rotating electric machinery with very complex magnetic circuit geometries, as well as nonlinear and anisotropic material properties.

Boosting the bioavailability of hydrophobic nutrients, vitamins, and nutraceuticals in natural products using excipient emulsions.

PubMed

McClements, David Julian; Saliva-Trujillo, Laura; Zhang, Ruojie; Zhang, Zipei; Zou, Liqiang; Yao, Mingfei; Xiao, Hang

2016-10-01

Many highly hydrophobic bioactives, such as non-polar nutrients, nutraceuticals, and vitamins, have a relatively low or variable oral bioavailability. The poor bioavailability profile of these bioactives may be due to limited bioaccessibility, poor absorption, and/or chemical transformation within the gastrointestinal tract (GIT). The bioavailability of hydrophobic bioactives can be improved using specially designed oil-in-water emulsions consisting of lipid droplets dispersed within an aqueous phase. The bioactives may be isolated from their natural environment and then incorporated into the lipid phase of emulsion-based delivery systems. Alternatively, the bioactives may be left in their natural environment (e.g., fruits or vegetables), and then ingested with emulsion-based excipient systems. An excipient emulsion may have no inherent health benefits itself, but it boosts the biological activity of bioactive ingredients co-ingested with it by altering their bioaccessibility, absorption, and/or chemical transformation. This review discusses the design and fabrication of excipient emulsions, and gives some examples of recent research that demonstrates their potential efficacy for improving the bioavailability of hydrophobic bioactives. The concept of excipient emulsions could be used to formulate emulsion-based food products (such as excipient sauces, dressings, dips, creams, or yogurts) specifically designed to increase the bioavailability of bioactive agents in natural foods, such as fruits and vegetables. Copyright © 2015 Elsevier Ltd. All rights reserved.

Augmentation method of XPNAV in Mars orbit based on Phobos and Deimos observations

NASA Astrophysics Data System (ADS)

Rong, Jiao; Luping, Xu; Zhang, Hua; Cong, Li

2016-11-01

Autonomous navigation for Mars probe spacecraft is required to reduce the operation costs and enhance the navigation performance in the future. X-ray pulsar-based navigation (XPNAV) is a potential candidate to meet this requirement. This paper addresses the use of the Mars' natural satellites to improve XPNAV for Mars probe spacecraft. Two observation variables of the field angle and natural satellites' direction vectors of Mars are added into the XPNAV positioning system. The measurement model of field angle and direction vectors is formulated by processing satellite image of Mars obtained from optical camera. This measurement model is integrated into the spacecraft orbit dynamics to build the filter model. In order to estimate position and velocity error of the spacecraft and reduce the impact of the system noise on navigation precision, an adaptive divided difference filter (ADDF) is applied. Numerical simulation results demonstrate that the performance of ADDF is better than Unscented Kalman Filter (UKF) DDF and EKF. In view of the invisibility of Mars' natural satellites in some cases, a visibility condition analysis is given and the augmented XPNAV in a different visibility condition is numerically simulated. The simulation results show that the navigation precision is evidently improved by using the augmented XPNAV based on the field angle and natural satellites' direction vectors of Mars in a comparison with the conventional XPNAV.

DNA/RNA-based formulations for treatment of breast cancer.

PubMed

Xie, Zhaolu; Zeng, Xianghui

2017-12-01

To develop a successful formulation for the gene therapy of breast cancer, an effective therapeutic nucleic acid and a proper delivery system are essential. Increased understanding of breast cancer, and developments in biotechnology, material science and nanotechnology have provided a major impetus in the development of effective formulations for the gene therapy of breast cancer. Areas covered: We discuss DNA/RNA-based formulations that can inhibit the growth of breast cancer cells and control the progress of breast cancer. Targets for the gene therapy of breast cancer, DNA/RNA-based therapeutics and delivery systems are summarized. And examples of successful DNA/RNA-based formulations for breast cancer gene therapy are reviewed. Expert opinion: Several challenges remain in developing effective DNA/RNA-based formulations for treatment of breast cancer. Firstly, most of the currently utilized targets are not effective enough as monotherapy for breast cancer. Secondly, the requirements for co-delivery system make the preparation of formulation more complicated. Thirdly, nanoparticles with the modification of tumor-targeting ligands could be more unstable in circulation and normal tissues. Lastly, immune responses against the viral vectors are unfavorable for the gene therapy of breast cancer because of the damage to the host and the impaired therapeutic ability.

Novel microemulsion-based gel formulation of tazarotene for therapy of acne.

PubMed

Patel, Mrunali Rashmin; Patel, Rashmin Bharatbhai; Parikh, Jolly R; Patel, Bharat G

2016-12-01

The objective of this study was to develop and evaluate a novel microemulsion based gel formulation containing tazarotene for targeted topical therapy of acne. Psudoternary phase diagrams were constructed to obtain the concentration range of oil, surfactant, and co-surfactant for microemulsion formation. The optimized microemulsion formulation containing 0.05% tazarotene was formulated by spontaneous microemulsification method consisting of 10% Labrafac CC, mixed emulsifiers 15% Labrasol-Cremophor-RH 40 (1:1), 15% Capmul MCM, and 60% distilled water (w/w) as an external phase. All plain and tazarotene-loaded microemulsions were clear and showed physicochemical parameters for desired topical delivery and stability. The permeation profiles of tazarotene through rat skin from optimized microemulsion formulation followed the Higuchi model for controlled permeation. Microemulsion-based gel was prepared by incorporating Carbopol®971P NF in optimized microemulsion formulation having suitable skin permeation rate and skin uptake. Microemulsion-based gel showed desired physicochemical parameters and demonstrated advantage over marketed formulation in improving the skin tolerability of tazarotene indicating its potential in improving its topical delivery. The developed microemulsion-based gel may be a potential drug delivery vehicle for targeted topical delivery of tazarotene in the treatment of acne.

Formulants of glyphosate-based herbicides have more deleterious impact than glyphosate on TM4 Sertoli cells.

PubMed

Vanlaeys, Alison; Dubuisson, Florine; Seralini, Gilles-Eric; Travert, Carine

2018-06-04

Roundup and Glyphogan are glyphosate-based herbicides containing the same concentration of glyphosate and confidential formulants. Formulants are declared as inert diluents but some are more toxic than glyphosate, such as the family of polyethoxylated alkylamines (POEA). We tested glyphosate alone, glyphosate-based herbicide formulations and POEA on the immature mouse Sertoli cell line (TM4), at concentrations ranging from environmental to agricultural-use levels. Our results show that formulations of glyphosate-based herbicides induce TM4 mitochondrial dysfunction (like glyphosate, but to a lesser extent), disruption of cell detoxification systems, lipid droplet accumulation and mortality at sub-agricultural doses. Formulants, especially those present in Glyphogan, are more deleterious than glyphosate and thus should be considered as active principles of these pesticides. Lipid droplet accumulation after acute exposure to POEA suggests the rapid penetration and accumulation of formulants, leading to mortality after 24 h. As Sertoli cells are essential for testicular development and normal onset of spermatogenesis, disturbance of their function by glyphosate-based herbicides could contribute to disruption of reproductive function demonstrated in mammals exposed to these pesticides at a prepubertal stage of development. Copyright © 2018 Elsevier Ltd. All rights reserved.

Medicinal Herbs Affecting Gray Hair in Iranian Traditional Medicine.

PubMed

Rameshk, Maryam; Khandani, Shahram Kalantari; Raeiszadeh, Mahboobeh

2016-05-01

The presence of hair plays an important role in people's overall physical appearance and self-perception. As a result of increased life expectancy, the desire to look youthful plays a bigger role than ever.The use of medicinal plants is as old as mankind and the market will face many new products containing natural oils and herbs in coming years. In traditional Iranian medicine, many plants and herbal formulations are reported for hair growth as well as the improvement in hair quality. The aim of this article is to introduce effective medicinal plants in traditional Iranian medicine to prevent gray hair and advocate them as the new products. The present investigation is an overview study and has been codified by library search in the main sources of traditional Iranian medicine. In traditional Iranian medicine, three types of formulations are proposed to prevent gray hair, namely (i) treatment compounds, (ii) preventive compounds, and (iii) hair dyes to color gray hairs. Our search showed that the main parts of a plant that is used in the treatment and preventive compounds are seeds and fruits. These are primarily in the form of topical oil or oral compound (electuary). The majority of plant parts used in hair dyes is from the fruit and/or leaves. Natural products are highly popular and the use of plant extracts in formulations is on the rise. This is because synthetic based product may cause health hazards with several side effects. Considering the increased popularity of herbal drugs in hair care, it is worthwhile to conduct systemic investigation on the production and efficacy of these drugs. We trust that our investigation would encourage the use of traditional Iranian medicine in future hair care products.

QbD-enabled systematic development of gastroretentive multiple-unit microballoons of itopride hydrochloride.

PubMed

Bansal, Sanjay; Beg, Sarwar; Asthana, Abhay; Garg, Babita; Asthana, Gyati Shilakari; Kapil, Rishi; Singh, Bhupinder

2016-01-01

The objectives of present studies were to develop the systematically optimized multiple-unit gastroretentive microballoons, i.e. hollow microspheres of itopride hydrochloride (ITH) employing quality by design (QbD)-based approach. Initially, the patient-centric QTPP and CQAs were earmarked, and preliminary studies were conducted to screen the suitable polymer, solvent, solvent ratio, pH and temperature conditions. Microspheres were prepared by non-aqueous solvent evaporation method employing Eudragit S-100. Risk assessment studies carried out by constructing Ishikawa cause-effect fish-bone diagram, and techniques like risk estimation matrix (REM) and failure mode effect analysis (FMEA) facilitated the selection of plausible factors affecting the drug product CQAs, i.e. percent yield, entrapment efficiency (EE) and percent buoyancy. A 3(3) Box-Behnken design (BBD) was employed for optimizing CMAs and CPPs selected during factor screening studies employing Taguchi design, i.e. drug-polymer ratio (X1), stirring temperature (X2) and stirring speed (X3). The hollow microspheres, as per BBD, were evaluated for EE, particle size and drug release characteristics. The optimum formulation was embarked upon using numerical desirability function yielding excellent floatation characteristics along with adequate drug release control. Drug-excipient compatibility studies employing FT-IR, DSC and powder XRD revealed absence of significant interaction among the formulation excipients. The SEM studies on the optimized formulation showed hollow and spherical nature of the prepared microspheres. In vivo X-ray imaging studies in rabbits confirmed the buoyant nature of the hollow microspheres for 8 h in the upper GI tract. In a nutshell, the current investigations report the successful development of gastroretentive floating microspheres for once-a-day administration of ITH.

Continuum theory of edge states of topological insulators: variational principle and boundary conditions.

PubMed

Medhi, Amal; Shenoy, Vijay B

2012-09-05

We develop a continuum theory to model low energy excitations of a generic four-band time reversal invariant electronic system with boundaries. We propose a variational energy functional for the wavefunctions which allows us to derive natural boundary conditions valid for such systems. Our formulation is particularly suited for developing a continuum theory of the protected edge/surface excitations of topological insulators both in two and three dimensions. By a detailed comparison of our analytical formulation with tight binding calculations of ribbons of topological insulators modelled by the Bernevig-Hughes-Zhang (BHZ) Hamiltonian, we show that the continuum theory with a natural boundary condition provides an appropriate description of the low energy physics.

Development and evaluation of a new alcohol-based surgical hand scrub formulation with persistent antimicrobial characteristics and brushless application.

PubMed

Hobson, D W; Woller, W; Anderson, L; Guthery, E

1998-10-01

Since the introduction in the 1970s of surgical hand scrub formulations that contain 4% chlorhexidine gluconate (CHG), new surgical scrub formulations that have improved efficacy, persistence, or significantly improved use characteristics have not been forthcoming. In addition, the manufacturer's labeling for popular hand scrub products generally requires scrub times in excess of 6 minutes, whereas current practical needs call for products with substantially shorter scrub times. A new alcohol-based surgical scrub formulation, which has ingredients that provide emollient, surfactant, and antimicrobial persistence characteristics to complement the rapid and broad-spectrum antiseptic qualities of alcohol, has been developed in an effort to address these current practical needs. The relative efficacy of a new alcohol-based surgical scrub formulation that contains ingredients that provide surfactant and antimicrobial persistence characteristics was compared with that of commercial 4% CHG and 7.5% povidone iodine (PVPI) formulations with use of human subjects. Hand antimicrobial count sampling was performed by using standardized "glove juice" methodology. The efficacy and persistence results of the new formulation showed statistically significant improvement over both CHG and PVPI at a substantially lessened scrub time (3 minutes). In addition, use of the new formulation without a scrub brush produced results statistically similar to 3-minute applications with either a brush or a sponge. The new alcohol-based formulation demonstrates promise as a new surgical hand scrub formulation with antimicrobial and use characteristics that are significantly improved over current CHG and PVPI formulations. These studies demonstrate the suitability of this formulation for use as a surgical hand scrub and for brushless application.

Antioxidant-based topical formulations influence on the inflammatory response of Japanese skin: A clinical study using non-invasive techniques.

PubMed

Wagemaker, Tais A L; Maia Campos, Patrícia M B G; Shimizu, Kenji; Kyotani, Daiki; Yoshida, Daisuke

2017-08-01

Cutaneous irritants exposure induces an excess of ROS in the skin and can ensue an inflammatory response. Topical antioxidant-based formulations can help to counteract ROS generation. This study evaluated the influence of antioxidant-based topical formulations on the inflammatory response of skin, using a combination of in vivo real-time non-invasive techniques. Nine test areas were defined on each volar forearm of the 25 Japanese volunteers. Measurements were performed before and after treatment with 15μL of a 5% sodium dodecyl sulfate solution and 15μL of the same based formulation or the vehicle with 1% of the antioxidants. Volunteers without antioxidant treatment showed more pronounced erythematous areas. Transepidermal water loss of areas treated with green tea polyphenol (GTP)-based formulation showed fully recovered skin. Skin barrier damage caused by repeated applications of SDS showed characteristic alterations, detectable by in vivo confocal microscopy such as desquamation, spongiosis and inflammatory infiltrates. The majority of confocal microscopy inflammation signs were found in skin without treatment followed by the vehicle. Ascorbyl tetraisopalmitate, Coenzyme Q 10 , GTP- and Resveratrol-based formulations reduced the anti-inflammatory cytokines release and attenuated inflammatory signs. The combination of techniques provides results that highlight the importance of antioxidant-based formulations for rapid skin recovery. Copyright © 2017 Elsevier B.V. All rights reserved.

Causal dissipation for the relativistic dynamics of ideal gases

NASA Astrophysics Data System (ADS)

Freistühler, Heinrich; Temple, Blake

2017-05-01

We derive a general class of relativistic dissipation tensors by requiring that, combined with the relativistic Euler equations, they form a second-order system of partial differential equations which is symmetric hyperbolic in a second-order sense when written in the natural Godunov variables that make the Euler equations symmetric hyperbolic in the first-order sense. We show that this class contains a unique element representing a causal formulation of relativistic dissipative fluid dynamics which (i) is equivalent to the classical descriptions by Eckart and Landau to first order in the coefficients of viscosity and heat conduction and (ii) has its signal speeds bounded sharply by the speed of light. Based on these properties, we propose this system as a natural candidate for the relativistic counterpart of the classical Navier-Stokes equations.

Identification of wild areas in southern lower Michigan. [terrain analysis from aerial photography, and satellite imagery

NASA Technical Reports Server (NTRS)

Habowski, S.; Cialek, C.

1978-01-01

An inventory methodology was developed to identify potential wild area sites. A list of site criteria were formulated and tested in six selected counties. Potential sites were initially identified from LANDSAT satellite imagery. A detailed study of the soil, vegetation and relief characteristics of each site based on both high-altitude aerial photographs and existing map data was conducted to eliminate unsuitable sites. Ground reconnaissance of the remaining wild areas was made to verify suitability and acquire information on wildlife and general aesthetics. Physical characteristics of the wild areas in each county are presented in tables. Maps show the potential sites to be set aside for natural preservation and regulation by the state under the Wilderness and Natural Areas Act of 1972.

Evaluation of RANS and LES models for Natural Convection in High-Aspect-Ratio Parallel Plate Channels

NASA Astrophysics Data System (ADS)

Fradeneck, Austen; Kimber, Mark

2017-11-01

The present study evaluates the effectiveness of current RANS and LES models in simulating natural convection in high-aspect ratio parallel plate channels. The geometry under consideration is based on a simplification of the coolant and bypass channels in the very high-temperature gas reactor (VHTR). Two thermal conditions are considered, asymmetric and symmetric wall heating with an applied heat flux to match Rayleigh numbers experienced in the VHTR during a loss of flow accident (LOFA). RANS models are compared to analogous high-fidelity LES simulations. Preliminary results demonstrate the efficacy of the low-Reynolds number k- ɛ formulations and their enhancement to the standard form and Reynolds stress transport model in terms of calculating the turbulence production due to buoyancy and overall mean flow variables.

Causal dissipation for the relativistic dynamics of ideal gases

PubMed Central

2017-01-01

We derive a general class of relativistic dissipation tensors by requiring that, combined with the relativistic Euler equations, they form a second-order system of partial differential equations which is symmetric hyperbolic in a second-order sense when written in the natural Godunov variables that make the Euler equations symmetric hyperbolic in the first-order sense. We show that this class contains a unique element representing a causal formulation of relativistic dissipative fluid dynamics which (i) is equivalent to the classical descriptions by Eckart and Landau to first order in the coefficients of viscosity and heat conduction and (ii) has its signal speeds bounded sharply by the speed of light. Based on these properties, we propose this system as a natural candidate for the relativistic counterpart of the classical Navier–Stokes equations. PMID:28588397

Causal dissipation for the relativistic dynamics of ideal gases.

PubMed

Freistühler, Heinrich; Temple, Blake

2017-05-01

We derive a general class of relativistic dissipation tensors by requiring that, combined with the relativistic Euler equations, they form a second-order system of partial differential equations which is symmetric hyperbolic in a second-order sense when written in the natural Godunov variables that make the Euler equations symmetric hyperbolic in the first-order sense. We show that this class contains a unique element representing a causal formulation of relativistic dissipative fluid dynamics which (i) is equivalent to the classical descriptions by Eckart and Landau to first order in the coefficients of viscosity and heat conduction and (ii) has its signal speeds bounded sharply by the speed of light. Based on these properties, we propose this system as a natural candidate for the relativistic counterpart of the classical Navier-Stokes equations.

Evaluation of Calendula mucilage as a mucoadhesive and controlled release component in buccal tablets.

PubMed

Sabale, V; Patel, V; Paranjape, A

2014-01-01

Mucoadhesive drug delivery systems were developed to sustain drug delivery via various mucus membranes for either local or systemic delivery of poorly absorbed drugs such as peptides and proteins as well as drugs that are subjected to high first-pass metabolism. The present study was undertaken to use isolated Calendula mucilage as a mucoadhesive agent and to formulate controlled release buccoadhesive tablets with an intention to avoid hepatic first-pass metabolism as well as to enhance residence time of drug in the buccal cavity. The mucilage was isolated from the Calendula petals by aqueous extraction method and characterized for various physiochemical parameters as well as for its adhesive properties. By using direct compression technique, tablets were prepared containing dried mucilage and chlorpheniramine maleate (CPM) as a model drug. Three batches of tablets were prepared and evaluated containing three mucoadhesive components namely Methocel K4M, Carbopol 974P and isolated Calendula mucilage in 16.66%, 33.33 % and 50 % (1:2:3 ratio) resulting in 9 different formulations. FTIR studies between mucilage and CPM suggested the absence of a chemical interaction between CPM and Calendula mucilage. The results of the study showed that the isolated mucilage had good physicochemical and morphological characteristics and tablets conformed to the pharmacopoeial specifications. Also in vitro release studies showed controlled action of drug with increasing the concentration of the isolated Calendula mucilage as a mucoadhesive agent in the formulations. Permeability studies indicated that permeability behavior was not statistically different (P>0.05) by changing the mucoadhesive component. The formulated mucoadhesive tablets for buccal administration containing 75 mg Calendula mucilage showed controlled drug release. Thus, mucoadhesive natural Calendula mucilage based buccal tablets for controlled release were successfully formulated.

Evaluation of Calendula mucilage as a mucoadhesive and controlled release component in buccal tablets

PubMed Central

Sabale, V.; Patel, V.; Paranjape, A.

2014-01-01

Mucoadhesive drug delivery systems were developed to sustain drug delivery via various mucus membranes for either local or systemic delivery of poorly absorbed drugs such as peptides and proteins as well as drugs that are subjected to high first-pass metabolism. The present study was undertaken to use isolated Calendula mucilage as a mucoadhesive agent and to formulate controlled release buccoadhesive tablets with an intention to avoid hepatic first-pass metabolism as well as to enhance residence time of drug in the buccal cavity. The mucilage was isolated from the Calendula petals by aqueous extraction method and characterized for various physiochemical parameters as well as for its adhesive properties. By using direct compression technique, tablets were prepared containing dried mucilage and chlorpheniramine maleate (CPM) as a model drug. Three batches of tablets were prepared and evaluated containing three mucoadhesive components namely Methocel K4M, Carbopol 974P and isolated Calendula mucilage in 16.66%, 33.33 % and 50 % (1:2:3 ratio) resulting in 9 different formulations. FTIR studies between mucilage and CPM suggested the absence of a chemical interaction between CPM and Calendula mucilage. The results of the study showed that the isolated mucilage had good physicochemical and morphological characteristics and tablets conformed to the pharmacopoeial specifications. Also in vitro release studies showed controlled action of drug with increasing the concentration of the isolated Calendula mucilage as a mucoadhesive agent in the formulations. Permeability studies indicated that permeability behavior was not statistically different (P>0.05) by changing the mucoadhesive component. The formulated mucoadhesive tablets for buccal administration containing 75 mg Calendula mucilage showed controlled drug release. Thus, mucoadhesive natural Calendula mucilage based buccal tablets for controlled release were successfully formulated. PMID:25598798

Cartan gravity, matter fields, and the gauge principle

NASA Astrophysics Data System (ADS)

Westman, Hans F.; Zlosnik, Tom G.

2013-07-01

Gravity is commonly thought of as one of the four force fields in nature. However, in standard formulations its mathematical structure is rather different from the Yang-Mills fields of particle physics that govern the electromagnetic, weak, and strong interactions. This paper explores this dissonance with particular focus on how gravity couples to matter from the perspective of the Cartan-geometric formulation of gravity. There the gravitational field is represented by a pair of variables: (1) a 'contact vector' VA which is geometrically visualized as the contact point between the spacetime manifold and a model spacetime being 'rolled' on top of it, and (2) a gauge connection AμAB, here taken to be valued in the Lie algebra of SO(2,3) or SO(1,4), which mathematically determines how much the model spacetime is rotated when rolled. By insisting on two principles, the gauge principle and polynomial simplicity, we shall show how one can reformulate matter field actions in a way that is harmonious with Cartan's geometric construction. This yields a formulation of all matter fields in terms of first order partial differential equations. We show in detail how the standard second order formulation can be recovered. In particular, the Hodge dual, which characterizes the structure of bosonic field equations, pops up automatically. Furthermore, the energy-momentum and spin-density three-forms are naturally combined into a single object here denoted the spin-energy-momentum three-form. Finally, we highlight a peculiarity in the mathematical structure of our first-order formulation of Yang-Mills fields. This suggests a way to unify a U(1) gauge field with gravity into a SO(1,5)-valued gauge field using a natural generalization of Cartan geometry in which the larger symmetry group is spontaneously broken down to SO(1,3)×U(1). The coupling of this unified theory to matter fields and possible extensions to non-Abelian gauge fields are left as open questions.

Bioavailability of organoclay formulations of atrazine in soil

USDA-ARS?s Scientific Manuscript database

Pesticide formulations based on organoclays have been proposed to prolong the efficacy and reduce the environmental impact of pesticides in soil. This research addressed the question of whether organoclay-based formulations of atrazine are irreversibly sorbed or are bioavailable for bacterial degrad...

Formulation and delivery of vaccines: Ongoing challenges for animal management

PubMed Central

Sharma, Sameer; Hinds, Lyn A.

2012-01-01

Development of a commercially successful animal vaccine is not only influenced by various immunological factors, such as type of antigen but also by formulation and delivery aspects. The latter includes the need for a vector or specific delivery system, the choice of route of administration and the nature of the target animal population and their habitat. This review describes the formulation and delivery aspects of various types of antigens such as killed microorganisms, proteins and nucleic acids for the development of efficacious and safe animal vaccines. It also focuses on the challenges associated with the different approaches that might be required for formulating and delivering species specific vaccines, particularly if their intended use is for improved animal management with respect to disease and/or reproductive control. PMID:23248557

Semisolid matrix filled capsules: an approach to improve dissolution stability of phenytoin sodium formulation.

PubMed

El Massik, M A; Abdallah, O Y; Galal, S; Daabis, N A

2003-05-01

Seven semisolid fill bases were selected for the formulation of 24 capsule formulations, each containing 100 mg of phenytoin sodium. The fill materials were selected based on the water absorption capacity of their mixtures with phenytoin sodium. The fill matrices included lipophilic bases (castor oil, soya oil, and Gelucire (G) 33/01), amphiphilic bases (G 44/14 and Suppocire BP), and water-soluble bases (PEG 4000 and PEG 6000). The drug:base ratio was 1:2. Excipients such as lecithin, docusate sodium, and poloxamer 188 were added to some formulations. The dissolution rate study indicated that formulations containing lipophilic and amphiphilic bases showed the best release profiles. These are F4 (castor oil-1% docusate sodium); F10 (castor oil-3% poloxamer 188); F14 (G33/01-10% lecithin); F17 (G33/01-1% docusate sodium), and F20 (Suppocire BP). Further, the dissolution stability of the five formulations above was assessed by an accelerated stability study at 30 degrees C and 75% RH using standard Epanutin capsules for comparison. The study included the test and standard capsules either packed in the container of marketed Epanutin capsules (packed) or removed from their outer pack (unpacked). Release data indicated superior release rates of castor oil based formulations (F4 and F10) relative to standard capsules in both the unpacked and packed forms. For instance, the extent of drug release at 30 min after 1 month was 91% for F4 and F10 and 20% for standard capsules. Drug release from packed capsules after 6 months storage was 88% for both formulations F4 and F10 and 35% for standard capsules. In conclusion, the pharmaceutical quality of phenytoin sodium capsules can be improved by using a semisolid lipophilic matrix filled in hard gelatin capsules.

Approaching mathematical model of the immune network based DNA Strand Displacement system.

PubMed

Mardian, Rizki; Sekiyama, Kosuke; Fukuda, Toshio

2013-12-01

One biggest obstacle in molecular programming is that there is still no direct method to compile any existed mathematical model into biochemical reaction in order to solve a computational problem. In this paper, the implementation of DNA Strand Displacement system based on nature-inspired computation is observed. By using the Immune Network Theory and Chemical Reaction Network, the compilation of DNA-based operation is defined and the formulation of its mathematical model is derived. Furthermore, the implementation on this system is compared with the conventional implementation by using silicon-based programming. From the obtained results, we can see a positive correlation between both. One possible application from this DNA-based model is for a decision making scheme of intelligent computer or molecular robot. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Variational formulation of high performance finite elements: Parametrized variational principles

NASA Technical Reports Server (NTRS)

Felippa, Carlos A.; Militello, Carmello

1991-01-01

High performance elements are simple finite elements constructed to deliver engineering accuracy with coarse arbitrary grids. This is part of a series on the variational basis of high-performance elements, with emphasis on those constructed with the free formulation (FF) and assumed natural strain (ANS) methods. Parametrized variational principles that provide a foundation for the FF and ANS methods, as well as for a combination of both are presented.

Bioactive evaluation and application of different formulations of the natural colorant curcumin (E100) in a hydrophilic matrix (yogurt).

PubMed

Almeida, Heloísa H S; Barros, Lillian; Barreira, João C M; Calhelha, Ricardo C; Heleno, Sandrina A; Sayer, Claudia; Miranda, Cristiane Grella; Leimann, Fernanda Vitória; Barreiro, Maria Filomena; Ferreira, Isabel C F R

2018-09-30

Curcumin (E100) is a natural colorant that, besides conferring color, has bioactivity, serving as an alternative to some artificial colorants. As a hydrophobic colorant, its modification/compatibilization with the aqueous medium is required to improve stability and enable its application in hydrophilic food matrices. Herein, different formulations of curcumin (curcumin powder: PC, water-dispersible curcumin: DC: and nanoencapsulated curcumin: NC) were evaluated as yogurt colorants. PC showed the strongest bioactivity in all assays (EC 50 values: 63 ± 2 to 7.9 ± 0.1 μg.mL -1 ; GI 50 values: 48 ± 1 to 17 ± 1 μg.mL -1 and MIC values: 0.0625 to 0.5 mg.mL -1 ), which might indicate that DC and NC reduce the short-term accessibility to curcumin. The tested curcumin formulations produced yogurts with different appearance, specifically associated with their color parameters, besides presenting slight changes in nutritional composition and free sugars and fatty acids profiles. The water compatible formulations (DC and NC) showed advantages over hydrophobic (PC) having a wider industrial utilization. Copyright © 2018 Elsevier Ltd. All rights reserved.

Co-encapsulated resveratrol and quercetin in chitosan and peg modified chitosan nanoparticles: For efficient intra ocular pressure reduction.

PubMed

Natesan, Subramanian; Pandian, Saravanakumar; Ponnusamy, Chandrasekar; Palanichamy, Rajaguru; Muthusamy, Sivakumar; Kandasamy, Ruckmani

2017-11-01

Natural anti-oxidants resveratrol (RES) and quercetin (QUR) posses the ability to reduce intra ocular pressure efficiently. Concurrent administration of RES and QUR was able to enhance the bioavailability of RES. Present research work describes upsurge of QUR in RES loaded chitosan (CS) nanoparticles (NPs) and polyethylene glycol (PEG) modified CS NPs for improved delivery and synergic effects on reducing intra ocular pressure for the treatment of glaucoma. CS NPs and PEG modified CS NPs were prepared by ionic gelation of tripolyphosphate and CS. The synthesised NPs were spherical in shape and RES entrapment and loading efficiency in the formulation decreased with increasing PEG concentration. Particle size of the formulation increased while incorporating PEG and drugs. The crystalline nature of RES and QUR changed in the NPs and that was confirmed by XRD study. Free radical neutralising efficiency improved while incorporating QUR in the formulation. Ex-vivo corneal permeation of RES was higher from RES and QUR loaded formulation than RES alone containing NPs and free RES dispersion. RES and QUR loaded PEG modified CS NPs showed sustained and enhanced reduction of intra ocular pressure (5.5±0.5mmHg) in normotensive rabbits. Copyright © 2017 Elsevier B.V. All rights reserved.

Frequency analysis of uncertain structures using imprecise probability

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

Modares, Mehdi; Bergerson, Joshua

2015-01-01

Two new methods for finite element based frequency analysis of a structure with uncertainty are developed. An imprecise probability formulation based on enveloping p-boxes is used to quantify the uncertainty present in the mechanical characteristics of the structure. For each element, independent variations are considered. Using the two developed methods, P-box Frequency Analysis (PFA) and Interval Monte-Carlo Frequency Analysis (IMFA), sharp bounds on natural circular frequencies at different probability levels are obtained. These methods establish a framework for handling incomplete information in structural dynamics. Numerical example problems are presented that illustrate the capabilities of the new methods along with discussionsmore » on their computational efficiency.« less

The utility of case formulation in treatment decision making; the effect of experience and expertise.

PubMed

Dudley, Robert; Ingham, Barry; Sowerby, Katy; Freeston, Mark

2015-09-01

We examined whether case formulation guides the endorsement of appropriate treatment strategies. We also considered whether experience and training led to more effective treatment decisions. To examine these questions two related studies were conducted both of which used a novel paradigm using clinically relevant decision-making tasks with multiple sources of information. Study one examined how clinicians utilised a pre-constructed CBT case formulation to plan treatment. Study two utilised a clinician-generated formulation to further examine the process of formulation development and the impact on treatment planning. Both studies considered the effect of therapist experience. Both studies indicated that clinicians used the case formulation to select treatment choices that were highly matched to the case as described in the vignette. However, differences between experts and novice clinicians were only demonstrated when clinicians developed their own formulations of case material. When they developed their own formulations the experts' formulations were more parsimonious, internally consistent, and contained fewer errors and the experts were less swayed by irrelevant treatment options. The nature of the experimental task, involving ratings of suitability of possible treatment options suggested for the case, limits the interpretation that formulation directs the development or generation of the clinician's treatment plan. In study two the task may still have limited the capacity to demonstrate further differences between expert and novice therapists. Formulation helps guide certain aspects of effective treatment decision making. When asked to generate a formulation clinicians with greater experience and expertise do this more effectively. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Free Vibration of Uncertain Unsymmetrically Laminated Beams

NASA Technical Reports Server (NTRS)

Kapania, Rakesh K.; Goyal, Vijay K.

2001-01-01

Monte Carlo Simulation and Stochastic FEA are used to predict randomness in the free vibration response of thin unsymmetrically laminated beams. For the present study, it is assumed that randomness in the response is only caused by uncertainties in the ply orientations. The ply orientations may become random or uncertain during the manufacturing process. A new 16-dof beam element, based on the first-order shear deformation beam theory, is used to study the stochastic nature of the natural frequencies. Using variational principles, the element stiffness matrix and mass matrix are obtained through analytical integration. Using a random sequence a large data set is generated, containing possible random ply-orientations. This data is assumed to be symmetric. The stochastic-based finite element model for free vibrations predicts the relation between the randomness in fundamental natural frequencies and the randomness in ply-orientation. The sensitivity derivatives are calculated numerically through an exact formulation. The squared fundamental natural frequencies are expressed in terms of deterministic and probabilistic quantities, allowing to determine how sensitive they are to variations in ply angles. The predicted mean-valued fundamental natural frequency squared and the variance of the present model are in good agreement with Monte Carlo Simulation. Results, also, show that variations between plus or minus 5 degrees in ply-angles can affect free vibration response of unsymmetrically and symmetrically laminated beams.

Application of inorganic carrier-based formulations of fluorescent pseudomonads and Piriformospora indica on tomato plants and evaluation of their efficacy.

PubMed

Sarma, M V R K; Kumar, V; Saharan, K; Srivastava, R; Sharma, A K; Prakash, A; Sahai, V; Bisaria, V S

2011-08-01

Fluorescent pseudomonads are widely used as bioinoculants for improving plant growth and controlling phytopathogenic fungi. Piriformospora indica (Pi), a symbiotic root endophyte, also has beneficial effects on a number of plants. The present study focuses on the improvement of growth yields of tomato plants and control of Fusarium wilt using inorganic carrier-based formulations of two fluorescent pseudomonad strains (R62 and R81) and Pi. The inorganic carrier-based formulations of pseudomonad strains and Pi were tested for plant growth promotion of tomato plants under glass house and field conditions. In controlled glass house experiments, 8·8-fold increase in dry root weight and 8·6-fold increase in dry shoot weight were observed with talcum powder-based consortium formulation of R81 and Pi. Field trial experiments ascertained the glfass house results with a considerable amount of increase in plant growth responses, and amongst all the treatments, R81 + Pi treatment performed consistently well in field conditions with an increase of 2·6-, 3·1- and 3·9-fold increase in dry root weight, shoot weight and fruit yield, respectively. The fluorescent pseudomonad R81 and Pi also acted as biocontrol agents, as their treatments could control the incidence of wilt disease caused by Fusarium oxysporum f.sp. lycopersici in tomato plants under glass house conditions. The culture broths of pseudomonads R62, R81 and Pi were successfully used for development of talcum- and vermiculite-based bioinoculant formulations. In controlled glasshouse experiments, the talcum-based bioinoculant formulations performed significantly better over vermiculite-based formulations. In field experiments the talcum-based consortium formulation of pseudomonad R81 and Pi was most effective. This study suggests that the formulations of pseudomonad strains (R62 and R81) and Pi can be used as bioinoculants for improving the productivity of tomato plants. The application of such formulations is a step forward towards sustainable agriculture. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

Effect of gellan gum on the thermogelation property and drug release profile of Poloxamer 407 based ophthalmic formulation.

PubMed

Dewan, Mitali; Sarkar, Gunjan; Bhowmik, Manas; Das, Beauty; Chattoapadhyay, Atis Kumar; Rana, Dipak; Chattopadhyay, Dipankar

2017-09-01

The effect of gellan gum on the gelation behavior and in-vitro release of a specific drug named pilocarpine hydrochloride from different ophthalmic formulations based on poloxamer 407 is examined. The mixture of 0.3wt% gellan gum and 18wt% poloxamer (PM) solutions show a considerable increase in gel strength in physiological condition. Gel dissolution rate from PM based formulation is significantly decreased due to the addition of gellan gum. FTIR spectra analysis witnesses an interaction in between OH groups of two polymers which accounts for lowering in gelation temperature of PM-gellan gum based formulations. It is also observed from the cryo-SEM study that the pore size of PM gel decreases with an addition of gellan gum and in-vitro release studies indicate that PM-gellan gum based formulation retain drug better than the PM solution alone. Therefore, the developed formulation has the potential to be utilized as an in-situ ophthalmic drug carrier. Copyright © 2017 Elsevier B.V. All rights reserved.

On roots and squares - estimation, intuition and creativity

NASA Astrophysics Data System (ADS)

Patkin, Dorit; Gazit, Avikam

2013-12-01

The paper presents findings of a small scale study of a few items related to problem solving with squares and roots, for different teacher groups (pre-service and in-service mathematics teachers: elementary and junior high school). The research participants were asked to explain what would be the units digit of a natural number to be squared in order to obtain a certain units digit as a result. They were also asked to formulate a rule - an algorithm for calculating the square of a 2-digit number which is a multiple of 5. Based on this knowledge and estimation capability, they were required to find, without using calculators, the square roots of given natural numbers. The findings show that most of the participants had only partial intuition regarding the units' digit of a number which is squared when the units' digit of the square is known. At the same time, the participants manifested some evidence of creativity and flow of ideas in identifying the rule for calculating the square of a natural number whose units digit is 5. However, when asked to identify, by means of estimation and based on knowledge from previous items, the square roots of three natural numbers, only few of them managed to find the three roots by estimation.

The Role of Soundscape in Nature-Based Rehabilitation: A Patient Perspective

PubMed Central

Cerwén, Gunnar; Pedersen, Eja; Pálsdóttir, Anna María

2016-01-01

Nature-based rehabilitation (NBR) has convincing support in research, yet the underlying mechanisms are not fully understood. The present study sought to increase understanding of the role of soundscapes in NBR, an aspect paid little attention thus far. Transcribed interviews with 59 patients suffering from stress-related mental disorders and undergoing a 12-week therapy programme in the rehabilitation garden in Alnarp, Sweden, were analysed using Interpretative Phenomenology Analysis (IPA). Described sounds were categorised as natural, technological or human. The results showed that patients frequently referred to natural sounds as being part of a pleasant and “quiet” experience that supported recovery and induced “soft fascination”. Technological sounds were experienced as disturbing, while perception of human sounds varied depending on loudness and the social context. The study further uncovered how sound influenced patients’ behaviour and experiences in the garden, through examination of three cross-theme dimensions that materialised in the study; sound in relation to overall perception, sound in relation to garden usage, and increased susceptibility to sound. The findings are discussed in relation to NBR; the need for a more nuanced understanding of susceptibility to sound among people suffering from mental fatigue was identified and design considerations for future rehabilitation gardens were formulated. PMID:27973437

Drug delivery strategies for Alzheimer's disease treatment.

PubMed

Di Stefano, Antonio; Iannitelli, Antonio; Laserra, Sara; Sozio, Piera

2011-05-01

Current Alzheimer's disease (AD) therapy is based on the administration of the drugs donepezil, galantamine, rivastigmine and memantine. Until disease-modifying therapies become available, further research is needed to develop new drug delivery strategies to ensure ease of administration and treatment persistence. In addition to the conventional oral formulations, a variety of drug delivery strategies applied to the treatment of AD are reviewed in this paper, with a focus on strategies leading to simplified dosage regimens and to providing new pharmacological tools. Alternatives include extended release, orally disintegrating or sublingual formulations, intranasal or short- and long-acting intramuscular or transdermal forms, and nanotechnology-based delivery systems. The advent of new research on molecular mechanisms of AD pathogenesis has outlined new strategies for therapeutic intervention; these include the stimulation of α-secretase cleavage, the inhibition of γ-secretase activity, the use of non-steroidal anti-inflammatory drugs, neuroprotection based on antioxidant therapy, the use of estrogens, NO synthetase inhibitors, and natural agents such as polyphenols. Unfortunately, these compounds might not help patients with end stage AD, but might hopefully slow or stop the disease process in its early stage. Nanotechnologies may prove to be a promising contribution in future AD drug delivery strategies, in particular drug carrier nano- or microsystems, which can limit the side effects of anti-Alzheimer drugs.

Nanoemulsion as pharmaceutical carrier for dermal and transdermal drug delivery: Formulation development, stability issues, basic considerations and applications.

PubMed

Rai, Vineet Kumar; Mishra, Nidhi; Yadav, Kuldeep Singh; Yadav, Narayan Prasad

2018-01-28

The use of nanoemulsion in augmenting dermal and transdermal effectiveness of drugs has now well established. The development of nanoemulsion based semisolid dosage forms is an active area of present research. However, thickening or liquid-to-semisolid conversion of the nanoemulsions provides opportunities to the formulation scientist to explore novel means of solving instability issues during transformation. Extending knowledge about the explicit role of nature/magnitude of zeta potential, types of emulsifiers and selection of appropriate semisolid bases could place these versatile carriers from laboratory to industrial scale. This article reviews the progressive advancement in the delivery of medicament via nanoemulsion with special reference to the dermal and transdermal administration. It is attempted to explore the most suitable semi solid dosage form for the particular type of nanoemulsion (o/w, w/o and others) and effect of particle size and zeta potential on the delivery of drugs through dermal or transdermal route. Finally, this review also highlights the basic principles and fundamental considerations of nanoemulsion manufacture, application of nanoemulsion based semisolid dosage forms in the dermal/transdermal administration and basic considerations during the nanoemulsion absorption into and through skin. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessment of Plant-Probiotic Performance of Novel Endophytic Bacillus sp. in Talc-Based Formulation.

PubMed

Basheer, Jasim; Ravi, Aswani; Mathew, Jyothis; Krishnankutty, Radhakrishnan Edayileveettil

2018-01-25

Endophytic bacteria are considered to have a plethora of plant growth promoting and anti-phytopathogenic traits to live within the plants. Hence, they have immense promises for plant probiotic development. In the current study, plant probiotic endophytic Bacillus sp. CaB5 which has been previously isolated from Capsicum annuum was investigated for its performance in talc-based formulation. For this, CaB5 was made into formulation with sterile talc, calcium carbonate, and carboxymethyl cellulose. The viability analysis of the formulation by standard plate count and fluorescence methods has confirmed the stable microbial count up to 45 days. Plant probiotic performance of the prepared formulation was analyzed on cowpea (Vigna unguiculata) and lady's finger (Abelmoschus esculentus). The results showed the formulation treatment to have enhancement effect on seed germination as well as plant growth in both selected plants. The results highlight the potential of CaB5-based formulation for field application to enhance growth of economically important plants.

Properties and mechanisms of surface doped barium titanate sintered in reducing atmospheres

NASA Astrophysics Data System (ADS)

Spang, David Irwin

2001-07-01

Barium titanate-based dielectric compositions for Multilayer Ceramic Capacitor (MLCC) applications that are properly formulated can maintain acceptable dielectric properties after firing in a reducing atmosphere. The data to be presented relates to the application of an experimental scheme to probe the fundamental nature of doped BaTiO3-based dielectrics exposed to low pO2 sintering atmospheres. Specifically, the effect of Y and Rare Earth dopants Nd, Dy, Ho, and Er and donor dopants Nb, and V have been studied for compositions in the system BaTi(Mn)O3 + SiO2. All dopants were applied to high purity barium titanate as chemical surface coatings. Each coated formulation was evaluated after firing under three different atmospheric conditions. These conditions were comprised of firing in air at 1250°C for 2 hours, firing at 10-10 atm pO2 at 1250°C for 2 hours, and firing at 10-10 atm pO2 at 1250°C for 2 hours with an anneal at 10 -9 atm pO2 at 1000°C for 1 hour. This testing method was useful in gaining insight into the mechanism of the dopant interaction and/or the compensation of the oxygen vacancy concentration. As a donor addition, vanadium was observed to produce the highest dissipation factor when sintered under oxidizing conditions and the lowest dissipation factor when sintered under reducing conditions. The V-doped formulations exhibited satisfactory basic MLCC electrical properties when sintered under reducing conditions. Niobium was observed to impart strong donor character to the dielectric formulations sintered under reducing conditions suggesting that it was unlikely that compensatory A-site cation vacancies were induced. For Y and Rare Earth doped formulations there was an observed shifting and suppression of the Curie Peak that seemed to be attributable to electrostrain effects, related to the ionic radius of the dopants. The observed difference in the TCC behavior of the Nd-doped formulations illustrated two possible effects of Nd doping. One is the effect of grain growth on Nd diffusion into the BaTiO3. The second is a possible effect of a change in the dopant solubility in regions of highly acceptor-rich oxygen vacancies. This result stresses the possible significance of surface coating powders to achieve carefully controlled chemical gradients.

Oxidative damage and antioxidant defense in Caiman latirostris (Broad-snouted caiman) exposed in ovo to pesticide formulations.

PubMed

Burella, P M; Odetti, L M; Simoniello, M F; Poletta, G L

2018-06-13

The surface used for agricultural production in Argentina significantly increased in recent years, mainly due to the expansion of soybean crops. As a result, the use of agrochemicals increased too. Many natural populations of Caiman latirostris (broad-snouted caiman) are affected by habitat fragmentation and the constant exposure to pesticides. This exposure could produce Reactive Oxygen Species. The negative imbalance between ROS generation and the capacity of the biological systems to eliminate the reactive intermediaries or avoid the damage is called Oxidative Stress. The aim of this study was to evaluate oxidative damage and antioxidant defense in C. latirostris hatchlings after in ovo exposure to widely used pesticide formulations. Embryos were exposed by topical exposure on the eggshell, from the beginning of incubation period, to sub-lethal concentrations of two glyphosate formulations: PanzerGold® (PANZ) and Roundup® Full II (RU): 500, 750, 1000 μg/egg; to the endosulfan (END) formulation Galgofan® and the cypermethrin (CYP) formulation Atanor®: 1, 10, 100, and 1000 μg/ egg. Blood samples were taken to all animals immediately after hatching for the application and comparison of the following oxidative stress biomarkers between the exposed groups and their respective controls: lipoperoxidation through thiobarbituric acid reactive substances (TBARS), DNA base oxidation through the modified comet assay, and the activities of Catalase (CAT) and Superoxide dismutase (SOD) in erythrocytes. Our results showed lipoperoxidation in caiman exposed to END (10, 100, 1000 µg/egg), CYP (1, 10, 1000 µg/egg), RU (500, 1000 µg/egg) and PANZ (500, 1000 µg/egg), DNA base oxidation in those exposed to END (10, 100, 1000 µg/egg), CYP (1, 10 µg/egg) and PANZ (500, 750 µg/egg) as well as alteration in the activity of SOD in END 1 µg/egg and CYP (10, 1000 µg/egg). This study demonstrated the incidence of oxidative stress in animals exposed to pesticide formulations widely used in agricultural activity associated mainly with soybean crops, and add further information to that previously reported about pesticide effects in this native reptile species. Copyright © 2018 Elsevier Inc. All rights reserved.

Biomimicry of surfactant protein C.

PubMed

Brown, Nathan J; Johansson, Jan; Barron, Annelise E

2008-10-01

Since the widespread use of exogenous lung surfactant to treat neonatal respiratory distress syndrome, premature infant survival and respiratory morbidity have dramatically improved. Despite the effectiveness of the animal-derived surfactant preparations, there still remain some concerns and difficulties associated with their use. This has prompted investigation into the creation of synthetic surfactant preparations. However, to date, no clinically used synthetic formulation is as effective as the natural material. This is largely because the previous synthetic formulations lacked analogues of the hydrophobic proteins of the lung surfactant system, SP-B and SP-C, which are critical functional constituents. As a result, recent investigation has turned toward the development of a new generation of synthetic, biomimetic surfactants that contain synthetic phospholipids along with a mimic of the hydrophobic protein portion of lung surfactant. In this Account, we detail our efforts in creating accurate mimics of SP-C for use in a synthetic surfactant replacement therapy. Despite SP-C's seemingly simple structure, the predominantly helical protein is extraordinarily challenging to work with given its extreme hydrophobicity and structural instability, which greatly complicates the creation of an effective SP-C analogue. Drawing inspiration from Nature, two promising biomimetic approaches have led to the creation of rationally designed biopolymers that recapitulate many of SP-C's molecular features. The first approach utilizes detailed SP-C structure-activity relationships and amino acid folding propensities to create a peptide-based analogue, SP-C33. In SP-C33, the problematic and metastable polyvaline helix is replaced with a structurally stable polyleucine helix and includes a well-placed positive charge to prevent aggregation. SP-C33 is structurally stable and eliminates the association propensity of the native protein. The second approach follows the same design considerations but makes use of a non-natural, poly-N-substituted glycine or "peptoid" scaffold to circumvent the difficulties associated with SP-C. By incorporating unique biomimetic side chains in a non-natural backbone, the peptoid mimic captures both SP-C's hydrophobic patterning and its helical secondary structure. Despite the differences in structure, both SP-C33 and the SP-C peptoid mimic capture many requisite features of SP-C. In a surfactant environment, these analogues also replicate many of the key surface activities necessary for a functional biomimetic surfactant therapy while overcoming the difficulties associated with the natural protein. With improved stability, greater production potential, and elimination of possible pathogenic contamination, these biomimetic surfactant formulations offer not only the potential to improve the treatment of respiratory distress syndrome but also the opportunity to treat other respiratory-related disorders.

Ultrasonication-assisted preparation and characterization of emulsions and emulsion gels for topical drug delivery.

PubMed

Singh, Vinay K; Behera, Baikuntha; Pramanik, Krishna; Pal, Kunal

2015-03-01

The current study describes the use of ultrasonication for the preparation of biphasic emulsions and emulsion gels for topical drug delivery. Sorbitan monostearate (SMS) was used as the surfactant for stabilizing the interface of sesame oil (apolar phase) and water (polar phase). Emulsions were formed at lower concentrations of SMS, whereas emulsion gels were formed at higher concentrations of SMS. The formulations were characterized by fluorescent microscopy, X-ray diffraction, viscosity, stress relaxation, spreadability, and differential scanning calorimetry studies. Fluorescence microscopy suggested formation of oil-in-water type of formulations. There was an increase in the viscosity, bulk resistance, and firmness of the formulations as the proportions of SMS was increased. The emulsion gels were viscoelastic in nature. Thermal studies suggested higher thermodynamic stability at higher proportions of either SMS or water. Metronidazole, a model antimicrobial drug, was incorporated within the formulations. The release of the drug from the formulations was found to be diffusion mediated. The drug-loaded formulations showed sufficient antimicrobial efficiency to be used as carriers for topical antimicrobial drug delivery. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

Formulation development of smart gel periodontal drug delivery system for local delivery of chemotherapeutic agents with application of experimental design.

PubMed

Dabhi, Mahesh R; Nagori, Stavan A; Gohel, Mukesh C; Parikh, Rajesh K; Sheth, Navin R

2010-01-01

Smart gel periodontal drug delivery systems (SGPDDS) containing gellan gum (0.1-0.8% w/v), lutrol F127 (14, 16, and 18% w/v), and ornidazole (1% w/v) were designed for the treatment of periodontal diseases. Each formulation was characterized in terms of in vitro gelling capacity, viscosity, rheology, content uniformity, in vitro drug release, and syringeability. In vitro gelation time and the nature of the gel formed in simulated saliva for prepared formulations showed polymeric concentration dependency. Drug release data from all formulations was fitted to different kinetic models and the Korsemeyer-Peppas model was the best fit model. Drug release was significantly decreased as the concentration of each polymer component was increased. Increasing the concentration of each polymeric component significantly increased viscosity, syringeability, and time for 50%, 70%, and 90% drug release. In conclusion, the formulations described offer a wide range of physical and drug release characteristics. The formulation containing 0.8% w/v of gellan gum and 16% w/v of lutrol F127 exhibited superior physical characteristics.

Automatic query formulations in information retrieval.

PubMed

Salton, G; Buckley, C; Fox, E A

1983-07-01

Modern information retrieval systems are designed to supply relevant information in response to requests received from the user population. In most retrieval environments the search requests consist of keywords, or index terms, interrelated by appropriate Boolean operators. Since it is difficult for untrained users to generate effective Boolean search requests, trained search intermediaries are normally used to translate original statements of user need into useful Boolean search formulations. Methods are introduced in this study which reduce the role of the search intermediaries by making it possible to generate Boolean search formulations completely automatically from natural language statements provided by the system patrons. Frequency considerations are used automatically to generate appropriate term combinations as well as Boolean connectives relating the terms. Methods are covered to produce automatic query formulations both in a standard Boolean logic system, as well as in an extended Boolean system in which the strict interpretation of the connectives is relaxed. Experimental results are supplied to evaluate the effectiveness of the automatic query formulation process, and methods are described for applying the automatic query formulation process in practice.

Game Theoretic Resolution of Water Conflicts

NASA Astrophysics Data System (ADS)

Tyagi, H.; Gosain, A. K.; Khosa, R.

2017-12-01

Water disputes are of multi-disciplinary nature and involve an array of natural, hydrological,social, political and economic issues. Operations Research based decision making methodshave been found to facilitate mathematical analysis of such multifaceted problems thatconsist of multiple stakeholders and their conflicting objectives. Game Theoretic techniqueslike Metagame and Hypergame Analysis can provide a framework for conceptualizing waterconflicts and envisaging their potential solutions. In the present research, firstly a Metagamemodel has been developed to identify range of plausible equilibrium outcomes for resolvingconflicts pertaining to water apportionments in a transboundary watercourse. Further, it hasbeen observed that the contenders often hide their strategies from other players to getfavorable water allocations. Consequently, there are widespread misinterpretations about thetactics of the competitors and contenders have to formulate their strategies entirely based ontheir perception about others. Accordingly, a Hypergame study has also been conducted tomodel the probable misperceptions that may exist amongst the river riparians. Thus, thecurrent study assesses the efficacy of Game Theoretic techniques as possible redressalmechanism for water conflicts.

Priming anticancer active specific immunotherapy with dendritic cells.

PubMed

Mocellin, Simone

2005-06-01

Dendritic cells (DCs) probably represent the most powerful naturally occurring immunological adjuvant for anticancer vaccines. However, the initial enthusiasm for DC-based vaccines is being tempered by clinical results not meeting expectations. The partial failure of current vaccine formulations is explained by the extraordinary complexity of the immune system, which makes the task of exploiting the potential of such a biotherapeutic approach highly challenging. Clinical findings obtained in humans so far indicate that the immune system can be actively polarized against malignant cells by means of DC-based active specific immunotherapy, and that in some cases this is associated with tumor regression. This implies that under some unique circumstances, the naturally 'dormant' immune effectors can actually be employed as endogenous weapons against malignant cells. Only the thorough understanding of DC biology and tumor-host immune system interactions will allow researchers to reproduce, in a larger set of patients, the cellular/molecular conditions leading to an effective immune-mediated eradication of cancer.

Comparison of the antifungal efficacy of terbinafine hydrochloride and ciclopirox olamine containing formulations against the dermatophyte Trichophyton rubrum in an infected nail plate model.

PubMed

Täuber, Anja; Müller-Goymann, Christel C

2014-07-07

Onychomycosis is a fungal infection mostly induced by dermatophytes such as Trichophyton rubrum. Due to slow nail growth, the treatment takes 3-9 months depending on the nail size and infected area. Hence, high efficacy of the active ingredient without systemic side effects is of major interest. To test the efficacy of an antifungal formulation, an appropriate in vitro model reflecting the in vivo situation as close as possible is required. In this study, a variety of antifungal formulations, i.e., commercial ones (Ciclopoli and Lamisil cream), those used in compounding pharmacies (Pentravan) as well as poloxamer 407-based systems, have been evaluated in an infected nail plate model. The active pharmaceutical ingredients (APIs) were ciclopirox olamine and terbinafine hydrochloride. The poloxamer 407-based formulations consisted of poloxamer 407, double distilled water, propylene glycol, isopropyl alcohol, medium chain triglycerides and either 1% ciclopirox olamine or 1% terbinafine hydrochloride as API, respectively. Former studies have shown high permeation rates of terbinafine hydrochloride from similar poloxamer 407-based formulations with dimethyl isosorbide instead of propylene glycol. The present contribution shows superior inhibition of T. rubrum growth from poloxamer 407-based formulations in comparison to the commercial Lamisil cream. Moreover, poloxamer 407-based formulations were equally effective as the nail lacquer Ciclopoli even though the poloxamer formulations contained only 1% of the drug instead of 8% in the marketed lacquer. Poloxamer 407-based systems containing ciclopirox olamine proved to be about as effective as similar terbinafine hydrochloride systems.

Analytical and experimental studies on detection of longitudinal, L and inverted T cracks in isotropic and bi-material beams based on changes in natural frequencies

NASA Astrophysics Data System (ADS)

Ravi, J. T.; Nidhan, S.; Muthu, N.; Maiti, S. K.

2018-02-01

An analytical method for determination of dimensions of longitudinal crack in monolithic beams, based on frequency measurements, has been extended to model L and inverted T cracks. Such cracks including longitudinal crack arise in beams made of layered isotropic or composite materials. A new formulation for modelling cracks in bi-material beams is presented. Longitudinal crack segment sizes, for L and inverted T cracks, varying from 2.7% to 13.6% of length of Euler-Bernoulli beams are considered. Both forward and inverse problems have been examined. In the forward problems, the analytical results are compared with finite element (FE) solutions. In the inverse problems, the accuracy of prediction of crack dimensions is verified using FE results as input for virtual testing. The analytical results show good agreement with the actual crack dimensions. Further, experimental studies have been done to verify the accuracy of the analytical method for prediction of dimensions of three types of crack in isotropic and bi-material beams. The results show that the proposed formulation is reliable and can be employed for crack detection in slender beam like structures in practice.

Multi Objective Optimization of Yarn Quality and Fibre Quality Using Evolutionary Algorithm

NASA Astrophysics Data System (ADS)

Ghosh, Anindya; Das, Subhasis; Banerjee, Debamalya

2013-03-01

The quality and cost of resulting yarn play a significant role to determine its end application. The challenging task of any spinner lies in producing a good quality yarn with added cost benefit. The present work does a multi-objective optimization on two objectives, viz. maximization of cotton yarn strength and minimization of raw material quality. The first objective function has been formulated based on the artificial neural network input-output relation between cotton fibre properties and yarn strength. The second objective function is formulated with the well known regression equation of spinning consistency index. It is obvious that these two objectives are conflicting in nature i.e. not a single combination of cotton fibre parameters does exist which produce maximum yarn strength and minimum cotton fibre quality simultaneously. Therefore, it has several optimal solutions from which a trade-off is needed depending upon the requirement of user. In this work, the optimal solutions are obtained with an elitist multi-objective evolutionary algorithm based on Non-dominated Sorting Genetic Algorithm II (NSGA-II). These optimum solutions may lead to the efficient exploitation of raw materials to produce better quality yarns at low costs.

A 4-node assumed-stress hybrid shell element with rotational degrees of freedom

NASA Technical Reports Server (NTRS)

Aminpour, Mohammad A.

1990-01-01

An assumed-stress hybrid/mixed 4-node quadrilateral shell element is introduced that alleviates most of the deficiencies associated with such elements. The formulation of the element is based on the assumed-stress hybrid/mixed method using the Hellinger-Reissner variational principle. The membrane part of the element has 12 degrees of freedom including rotational or drilling degrees of freedom at the nodes. The bending part of the element also has 12 degrees of freedom. The bending part of the element uses the Reissner-Mindlin plate theory which takes into account the transverse shear contributions. The element formulation is derived from an 8-node isoparametric element. This process is accomplished by assuming quadratic variations for both in-plane and out-of-plane displacement fields and linear variations for both in-plane and out-of-plane rotation fields along the edges of the element. In addition, the degrees of freedom at midside nodes are approximated in terms of the degrees of freedom at corner nodes. During this process the rotational degrees of freedom at the corner nodes enter into the formulation of the element. The stress field are expressed in the element natural-coordinate system such that the element remains invariant with respect to node numbering.

Injectable thermosensitive chitosan/glycerophosphate-based hydrogels for tissue engineering and drug delivery applications: a review.

PubMed

Tahrir, Farzaneh G; Ganji, Fariba; Ahooyi, Taha M

2015-01-01

Recently, great attention has been paid to in situ gel-forming chitosan/glycerophosphate (CS/Gp) formulation due to its high biocompatibility with incorporated cells and medical agents, biodegradability and sharp thermosensitive gelation. CS/Gp is in liquid state at room temperature and after minimally invasive administration into the desired tissue, it forms a solid-like gel as a response to temperature increase. The overview of various recently patented strategies on injectable delivery systems indicates the significance of this formulation in biomedical applications. This thermosensitive hydrogel has a great potential as scaffold material in tissue engineering, due to its good biocompatibility, minimal immune reaction, high antibacterial nature, good adhesion to cells and the ability to be molded in various geometries. Moreover, CS/Gp hydrogel has been utilized as a smart drug delivery system to increase patient compliance by maintaining the drug level in the therapeutic window for a long time while avoiding the need for frequent injections of the therapeutic agent. This review paper highlights the recent patents and investigations on different formulations of CS/Gp hydrogels as tissue engineering scaffolds and carriers for therapeutic agents. Additionally, the dominant mechanism of sol-gel transition in those systems as well as their physicochemical properties and biocompatibility are discussed in detail.

Pectin-based oral drug delivery to the colon.

PubMed

Sande, Sverre Arne

2005-05-01

This review presents an overview of studies concerning oral formulations intended for site-specific drug delivery to the colon with pectin as the main excipient. The biological aspects covered include gastrointestinal transit and the enzymatic degradation of pectin. Scintigraphic methods demonstrating the functionality of pectin formulations are discussed. The main focus is on the various formulations reported, including matrix tablets, multiparticulate formulations as pellets and hydrogel beads, and pectin-based coatings. Also included is an evaluation of common excipients employed to improve colon specificity by crosslinking or increasing the hydrophobicity. Finally, properties of the pectin molecules that are important for successful formulations are examined. The conclusion is that the studies found in the literature provide an excellent platform for the development of pectin-based colon delivery systems.

Green and ecofriendly synthesis of silver nanoparticles: Characterization, biocompatibility studies and gel formulation for treatment of infections in burns.

PubMed

Jadhav, Kiran; Dhamecha, Dinesh; Bhattacharya, Debdutta; Patil, Mrityunjaya

2016-02-01

The current study summarizes a unique green process for the synthesis of silver nanoparticles (AgNPs) by simple treatment of silver nitrate with aqueous extract of Ammania baccifera. Phytosynthesized AgNPs were characterized by various advanced analytical methods and studied for its use against infections associated with burns. Formation of AgNPs was observed by visual color change from colorless to dark brown and confirmed by UV-visible characteristic peak at 436 nm. Zeta potential, particle size and polydispersity index of nano-silver were found to be -33.1 ± 1.12, 112.6 ± 6.8 nm and 0.3 ± 0.06 respectively. XRD spectra revealed crystalline nature of AgNPs whereas TEM confirmed the presence of mixed morphology of AgNPs. The overall approach designated in the present research investigation for the synthesis of AgNPs is based on all 12 principles of green chemistry, in which no man-made chemical other than the silver nitrate was used. Synthesized nano-silver colloidal dispersion was initially tested for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against a panel of organisms involved in infections associated with burns (Pseudomonas aeruginosa (PA), Staphylococcus aureus (SA) and methicillin resistant S. aureus (MRSA)). MIC and MBC were found to be in range of 0.992 to 7.93 and 7.93 to 31.75 μg/mL respectively. MBC was used for formulation of AgNP gel and tested for its efficacy using agar well diffusion method against PA, SA and MRSA. Comparative bactericidal efficacy of formulated gel (0.03% w/w) and marked formulation Silverex™ ionic (silver nitrate gel 0.2% w/w) showed equal zone of inhibition against all pathogenic bacteria. Formulated AgNP gel consisting of 95% lesser concentration of silver compared to marketed formulation was found to be equally effective against all organisms. Hence, the formulated AgNP gel could serve as a better alternative with least toxicity towards the treatment presently available for infections in burns. Copyright © 2016 Elsevier B.V. All rights reserved.

Design and formulation of a topical hydrogel integrating lemongrass-loaded nanosponges with an enhanced antifungal effect: in vitro/in vivo evaluation.

PubMed

Aldawsari, Hibah M; Badr-Eldin, Shaimaa M; Labib, Gihan S; El-Kamel, Amal H

2015-01-01

Lemongrass oil (LGO) is a volatile oil extracted from the leaves of Cymbopogon citratus that has become one of the most important natural oils in the pharmaceutical industry because of its diverse pharmacologic and clinical effects. However, LGO suffers from low aqueous solubility, which could lead to a reduced effect. Moreover, the instability of its major active constituent, citral, could lead to volatilization, reaction with other formulation ingredients, and consequently, skin irritation. To surmount these problems, this research aims to formulate lemongrass-loaded ethyl cellulose nanosponges with a topical hydrogel with an enhanced antifungal effect and decreased irritation. The minimal inhibitory concentration and minimal fungicidal concentration of LGO against Candida albicans strain ATC 100231, determined using the broth macrodilution method, were found to be 2 and 8 μL/mL, respectively. The emulsion solvent evaporation technique was used for the preparation of the nanosponges. The nanosponge dispersions were then integrated into carbopol hydrogels (0.4%). Nine formulations were prepared based on a 32 full factorial design employing the ethyl cellulose:polyvinyl alcohol ratio and stirring rate as independent variables. The prepared formulations were evaluated for particle size, citral content, and in vitro release. Results revealed that all the nanosponge dispersions were nanosized, with satisfactory citral content and sustained release profiles. Statistical analysis revealed that both ethyl cellulose:polyvinyl alcohol ratio and stirring rate have significant effects on particle size and percentage released after 6 hours; however, the effect of the stirring rate was more prominent on both responses. The selected hydrogel formulation, F9, was subjected to surface morphological investigations, using scanning and transmission electron microscopy, where results showed that the nanosponges possess a spherical uniform shape with a spongy structure, the integrity of which was not affected by integration into the hydrogel. Furthermore, the selected formulation, F9, was tested for skin irritation and antifungal activity against C. albicans, where results confirmed the nonirritancy and the effective antifungal activity of the prepared hydrogel.

Design and formulation of a topical hydrogel integrating lemongrass-loaded nanosponges with an enhanced antifungal effect: in vitro/in vivo evaluation

PubMed Central

Aldawsari, Hibah M; Badr-Eldin, Shaimaa M; Labib, Gihan S; El-Kamel, Amal H

2015-01-01

Lemongrass oil (LGO) is a volatile oil extracted from the leaves of Cymbopogon citratus that has become one of the most important natural oils in the pharmaceutical industry because of its diverse pharmacologic and clinical effects. However, LGO suffers from low aqueous solubility, which could lead to a reduced effect. Moreover, the instability of its major active constituent, citral, could lead to volatilization, reaction with other formulation ingredients, and consequently, skin irritation. To surmount these problems, this research aims to formulate lemongrass-loaded ethyl cellulose nanosponges with a topical hydrogel with an enhanced antifungal effect and decreased irritation. The minimal inhibitory concentration and minimal fungicidal concentration of LGO against Candida albicans strain ATC 100231, determined using the broth macrodilution method, were found to be 2 and 8 μL/mL, respectively. The emulsion solvent evaporation technique was used for the preparation of the nanosponges. The nanosponge dispersions were then integrated into carbopol hydrogels (0.4%). Nine formulations were prepared based on a 32 full factorial design employing the ethyl cellulose:polyvinyl alcohol ratio and stirring rate as independent variables. The prepared formulations were evaluated for particle size, citral content, and in vitro release. Results revealed that all the nanosponge dispersions were nanosized, with satisfactory citral content and sustained release profiles. Statistical analysis revealed that both ethyl cellulose:polyvinyl alcohol ratio and stirring rate have significant effects on particle size and percentage released after 6 hours; however, the effect of the stirring rate was more prominent on both responses. The selected hydrogel formulation, F9, was subjected to surface morphological investigations, using scanning and transmission electron microscopy, where results showed that the nanosponges possess a spherical uniform shape with a spongy structure, the integrity of which was not affected by integration into the hydrogel. Furthermore, the selected formulation, F9, was tested for skin irritation and antifungal activity against C. albicans, where results confirmed the nonirritancy and the effective antifungal activity of the prepared hydrogel. PMID:25673986

Trail pheromone disruption of Argentine ant trail formation and foraging.

PubMed

Suckling, David Maxwell; Peck, Robert W; Stringer, Lloyd D; Snook, Kirsten; Banko, Paul C

2010-01-01

Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2–3 m s−1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments.

Development and characterization of nanoparticulate formulation of a water soluble prodrug of dexamethasone by HIP complexation.

PubMed

Gaudana, Ripal; Parenky, Ashwin; Vaishya, Ravi; Samanta, Swapan K; Mitra, Ashim K

2011-01-01

The objective of this study was to develop and characterize a nanoparticulate-based sustained release formulation of a water soluble dipeptide prodrug of dexamethasone, valine-valine-dexamethasone (VVD). Being hydrophilic in nature, it readily leaches out in the external aqueous medium and hence partitions poorly into the polymeric matrix resulting in minimal entrapment in nanoparticles. Hence, hydrophobic ion pairing (HIP) complexation of the prodrug was employed with dextran sulphate as a complexing polymer. A novel, solid in oil in water emulsion method was employed to encapsulate the prodrug in HIP complex form in poly(lactic-co-glycolic acid) matrix. Nanoparticles were characterized with respect to size, zeta potential, crystallinity of entrapped drug and surface morphology. A significant enhancement in the entrapment of the prodrug in nanoparticles was achieved. Finally, a simple yet novel method was developed which can also be applicable to encapsulate other charged hydrophilic molecules, such as peptides and proteins.

SfM with MRFs: discrete-continuous optimization for large-scale structure from motion.

PubMed

Crandall, David J; Owens, Andrew; Snavely, Noah; Huttenlocher, Daniel P

2013-12-01

Recent work in structure from motion (SfM) has built 3D models from large collections of images downloaded from the Internet. Many approaches to this problem use incremental algorithms that solve progressively larger bundle adjustment problems. These incremental techniques scale poorly as the image collection grows, and can suffer from drift or local minima. We present an alternative framework for SfM based on finding a coarse initial solution using hybrid discrete-continuous optimization and then improving that solution using bundle adjustment. The initial optimization step uses a discrete Markov random field (MRF) formulation, coupled with a continuous Levenberg-Marquardt refinement. The formulation naturally incorporates various sources of information about both the cameras and points, including noisy geotags and vanishing point (VP) estimates. We test our method on several large-scale photo collections, including one with measured camera positions, and show that it produces models that are similar to or better than those produced by incremental bundle adjustment, but more robustly and in a fraction of the time.

Biomechanics as a window into the neural control of movement

PubMed Central

2016-01-01

Abstract Biomechanics and motor control are discussed as parts of a more general science, physics of living systems. Major problems of biomechanics deal with exact definition of variables and their experimental measurement. In motor control, major problems are associated with formulating currently unknown laws of nature specific for movements by biological objects. Mechanics-based hypotheses in motor control, such as those originating from notions of a generalized motor program and internal models, are non-physical. The famous problem of motor redundancy is wrongly formulated; it has to be replaced by the principle of abundance, which does not pose computational problems for the central nervous system. Biomechanical methods play a central role in motor control studies. This is illustrated with studies with the reconstruction of hypothetical control variables and those exploring motor synergies within the framework of the uncontrolled manifold hypothesis. Biomechanics and motor control have to merge into physics of living systems, and the earlier this process starts the better. PMID:28149390

Development and characterization of nanoparticulate formulation of a water soluble prodrug of dexamethasone by HIP complexation

PubMed Central

Gaudana, Ripal; Parenky, Ashwin; Vaishya, Ravi; Samanta, Swapan K.; Mitra, Ashim K.

2015-01-01

The objective of this study was to develop and characterize a nanoparticulate-based sustained release formulation of a water soluble dipeptide prodrug of dexamethasone, valine–valine-dexamethasone (VVD). Being hydrophilic in nature, it readily leaches out in the external aqueous medium and hence partitions poorly into the polymeric matrix resulting in minimal entrapment in nanoparticles. Hence, hydrophobic ion pairing (HIP) complexation of the prodrug was employed with dextran sulphate as a complexing polymer. A novel, solid in oil in water emulsion method was employed to encapsulate the prodrug in HIP complex form in poly(lactic-co-glycolic acid) matrix. Nanoparticles were characterized with respect to size, zeta potential, crystallinity of entrapped drug and surface morphology. A significant enhancement in the entrapment of the prodrug in nanoparticles was achieved. Finally, a simple yet novel method was developed which can also be applicable to encapsulate other charged hydrophilic molecules, such as peptides and proteins. PMID:20939702

Analytical methodology for determination of helicopter IFR precision approach requirements. [pilot workload and acceptance level

NASA Technical Reports Server (NTRS)

Phatak, A. V.

1980-01-01

A systematic analytical approach to the determination of helicopter IFR precision approach requirements is formulated. The approach is based upon the hypothesis that pilot acceptance level or opinion rating of a given system is inversely related to the degree of pilot involvement in the control task. A nonlinear simulation of the helicopter approach to landing task incorporating appropriate models for UH-1H aircraft, the environmental disturbances and the human pilot was developed as a tool for evaluating the pilot acceptance hypothesis. The simulated pilot model is generic in nature and includes analytical representation of the human information acquisition, processing, and control strategies. Simulation analyses in the flight director mode indicate that the pilot model used is reasonable. Results of the simulation are used to identify candidate pilot workload metrics and to test the well known performance-work-load relationship. A pilot acceptance analytical methodology is formulated as a basis for further investigation, development and validation.

Rational approach for assumed stress finite elements

NASA Technical Reports Server (NTRS)

Pian, T. H. H.; Sumihara, K.

1984-01-01

A new method for the formulation of hybrid elements by the Hellinger-Reissner principle is established by expanding the essential terms of the assumed stresses as complete polynomials in the natural coordinates of the element. The equilibrium conditions are imposed in a variational sense through the internal displacements which are also expanded in the natural co-ordinates. The resulting element possesses all the ideal qualities, i.e. it is invariant, it is less sensitive to geometric distortion, it contains a minimum number of stress parameters and it provides accurate stress calculations. For the formulation of a 4-node plane stress element, a small perturbation method is used to determine the equilibrium constraint equations. The element has been proved to be always rank sufficient.

Research on Captive Broodstock Programs for Pacific Salmon, 2000-2001 Annual Report.

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

Berejikian, Barry A.; Dittman, Andrew H.; Hardy, Ronald W.

It is not yet possible to define a feeding regimen for captively-reared stocks similar to their natural regimen that enhances the post-release fitness of juveniles and improves the reproductive performance of adults. In the natural environment, seasonal differences in food quality and quantity have profound effects on growth and 'wild' attributes, such as external coloration and fin quality. Formulating the right feeds for conservation fish held for long periods in captivity before release is more complicated than formulating diets for farm fish. Recent research in salmonid nutrition shows it is necessary to consider daily dietary protein intake and protein intakemore » relative to total dietary energy level, rather than simply the levels of total dietary lipid.« less

Nature in economic theories: Hans Immler traces recognition of the environment - and its neglect - in various classics

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

Karsten, S.G.

1987-01-01

Labor and capital are usually considered as the primary factors of production, the costs of which are of utmost importance. In contrast, nature (including all natural resources), as the essential third factor, is disregarded. She is generally assumed to be always available, self-regenerating, and to be exploited without long-term costs. In other words, she is more or less viewed as a constant. Hans Immler's new treatise represents an important contribution in that he emphasized the role and function of the natural environment, and its neglect, in the formulation of theories of value and their long-term consequences on contemporary economic theoriesmore » and on the person and society. This essay traces Immler's evaluation with extensive quotations - especially with regard to Physiocracy and the classical economists - of nature's role and function, or their neglect, in the formulation of theories of value through the writings of Aristotle, St. Thomas Aquinas, William Petty, John Locke, Adam Smith, David Ricardo, Karl Marx, and others, - all dealt with in Part 1 of his book - and Francois Quesnay and the Physiocrats - the topic of Part 2.« less

Design of two-channel filter bank using nature inspired optimization based fractional derivative constraints.

PubMed

Kuldeep, B; Singh, V K; Kumar, A; Singh, G K

2015-01-01

In this article, a novel approach for 2-channel linear phase quadrature mirror filter (QMF) bank design based on a hybrid of gradient based optimization and optimization of fractional derivative constraints is introduced. For the purpose of this work, recently proposed nature inspired optimization techniques such as cuckoo search (CS), modified cuckoo search (MCS) and wind driven optimization (WDO) are explored for the design of QMF bank. 2-Channel QMF is also designed with particle swarm optimization (PSO) and artificial bee colony (ABC) nature inspired optimization techniques. The design problem is formulated in frequency domain as sum of L2 norm of error in passband, stopband and transition band at quadrature frequency. The contribution of this work is the novel hybrid combination of gradient based optimization (Lagrange multiplier method) and nature inspired optimization (CS, MCS, WDO, PSO and ABC) and its usage for optimizing the design problem. Performance of the proposed method is evaluated by passband error (ϕp), stopband error (ϕs), transition band error (ϕt), peak reconstruction error (PRE), stopband attenuation (As) and computational time. The design examples illustrate the ingenuity of the proposed method. Results are also compared with the other existing algorithms, and it was found that the proposed method gives best result in terms of peak reconstruction error and transition band error while it is comparable in terms of passband and stopband error. Results show that the proposed method is successful for both lower and higher order 2-channel QMF bank design. A comparative study of various nature inspired optimization techniques is also presented, and the study singles out CS as a best QMF optimization technique. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Density-based global sensitivity analysis of sheet-flow travel time: Kinematic wave-based formulations

NASA Astrophysics Data System (ADS)

Hosseini, Seiyed Mossa; Ataie-Ashtiani, Behzad; Simmons, Craig T.

2018-04-01

Despite advancements in developing physics-based formulations to estimate the sheet-flow travel time (tSHF), the quantification of the relative impacts of influential parameters on tSHF has not previously been considered. In this study, a brief review of the physics-based formulations to estimate tSHF including kinematic wave (K-W) theory in combination with Manning's roughness (K-M) and with Darcy-Weisbach friction formula (K-D) over single and multiple planes is provided. Then, the relative significance of input parameters to the developed approaches is quantified by a density-based global sensitivity analysis (GSA). The performance of K-M considering zero-upstream and uniform flow depth (so-called K-M1 and K-M2), and K-D formulae to estimate the tSHF over single plane surface were assessed using several sets of experimental data collected from the previous studies. The compatibility of the developed models to estimate tSHF over multiple planes considering temporal rainfall distributions of Natural Resources Conservation Service, NRCS (I, Ia, II, and III) are scrutinized by several real-world examples. The results obtained demonstrated that the main controlling parameters of tSHF through K-D and K-M formulae are the length of surface plane (mean sensitivity index T̂i = 0.72) and flow resistance (mean T̂i = 0.52), respectively. Conversely, the flow temperature and initial abstraction ratio of rainfall have the lowest influence on tSHF (mean T̂i is 0.11 and 0.12, respectively). The significant role of the flow regime on the estimation of tSHF over a single and a cascade of planes are also demonstrated. Results reveal that the K-D formulation provides more precise tSHF over the single plane surface with an average percentage of error, APE equal to 9.23% (the APE for K-M1 and K-M2 formulae were 13.8%, and 36.33%, respectively). The superiority of Manning-jointed formulae in estimation of tSHF is due to the incorporation of effects from different flow regimes as flow moves downgradient that is affected by one or more factors including high excess rainfall intensities, low flow resistance, high degrees of imperviousness, long surfaces, steep slope, and domination of rainfall distribution as NRCS Type I, II, or III.

High Throughput Differential Scanning Fluorimetry (DSF) Formulation Screening with Complementary Dyes to Assess Protein Unfolding and Aggregation in Presence of Surfactants.

PubMed

McClure, Sean M; Ahl, Patrick L; Blue, Jeffrey T

2018-03-05

The purpose was to evaluate DSF for high throughput screening of protein thermal stability (unfolding/ aggregation) across a wide range of formulations. Particular focus was exploring PROTEOSTAT® - a commercially available fluorescent rotor dye - for detection of aggregation in surfactant containing formulations. Commonly used hydrophobic dyes (e.g. SYPRO™ Orange) interact with surfactants, complicating DSF measurements. CRM197 formulations were prepared and analyzed in standard 96-well plate rT-PCR system, using SYPRO™ Orange and PROTEOSTAT® dyes. Orthogonal techniques (DLS and IPF) are employed to confirm unfolding/aggregation in selected formulations. Selected formulations are subjected to non-thermal stresses (stirring and shaking) in plate based format to characterize aggregation with PROTEOSTAT®. Agreement is observed between SYPRO™ Orange (unfolding) and PROTEOSTAT® (aggregation) DSF melt temperatures across wide range of non-surfactant formulations. PROTEOSTAT® can clearly detect temperature induced aggregation in low concentration (0.2 mg/mL) CRM197 formulations containing surfactant. PROTEOSTAT® can be used to explore aggregation due to non-thermal stresses in plate based format amenable to high throughput screening. DSF measurements with complementary extrinsic dyes (PROTEOSTAT®, SYPRO™ Orange) are suitable for high throughput screening of antigen thermal stability, across a wide range of relevant formulation conditions - including surfactants -with standard, plate based rT-PCR instrumentation.

Dynamics of local grid manipulations for internal flow problems

NASA Technical Reports Server (NTRS)

Eiseman, Peter R.; Snyder, Aaron; Choo, Yung K.

1991-01-01

The control point method of algebraic grid generation is briefly reviewed. The review proceeds from the general statement of the method in 2-D unencumbered by detailed mathematical formulation. The method is supported by an introspective discussion which provides the basis for confidence in the approach. The more complex 3-D formulation is then presented as a natural generalization. Application of the method is carried out through 2-D examples which demonstrate the technique.

Light harvesting over a wide range of wavelength using natural dyes of gardenia and cochineal for dye-sensitized solar cells.

PubMed

Park, Kyung-Hee; Kim, Tae-Young; Han, Shin; Ko, Hyun-Seok; Lee, Suk-Ho; Song, Yong-Min; Kim, Jung-Hun; Lee, Jae-Wook

2014-07-15

Two natural dyes extracted from gardenia yellow (Gardenia jasminoides) and cochineal (Dactylopius coccus) were used as sensitizers in the assembly of dye-sensitized solar cells (DSSCs) to harvest light over a wide range of wavelengths. The adsorption characteristics, electrochemical properties and photovoltaic efficiencies of the natural DSSCs were investigated. The adsorption kinetics data of the dyes were obtained in a small adsorption chamber and fitted with a pseudo-second-order model. The photovoltaic performance of a photo-electrode adsorbed with single-dye (gardenia or cochineal) or the mixture or successive adsorption of the two dyes, was evaluated from current-voltage measurements. The energy conversion efficiency of the TiO2 electrode with the successive adsorption of cochineal and gardenia dyes was 0.48%, which was enhanced compared to single-dye adsorption. Overall, a double layer of the two natural dyes as sensitizers was successfully formulated on the nanoporous TiO2 surface based on the differences in their adsorption affinities of gardenia and cochineal. Copyright © 2014 Elsevier B.V. All rights reserved.

Medicine, natural philosophy, and the influence of Melanchthon in reformation Denmark and Norway.

PubMed

Fink-Jensen, Morten

2006-01-01

In the sixteenth and early seventeenth centuries, all intellectual pursuits in Europe were colored by the religious conditions of the age. Accordingly, investigations into nature were unable to avoid issues dealing with the workings of divine power. The reestablishment of the University of Copenhagen after the Reformation of 1536 in the joint kingdom of Denmark and Norway prompted the formulation of an official Lutheran program for the study of medicine and natural philosophy (including anatomy). This program was wholly based on the ideas of the German reformer Philip Melanchthon, the aim being to apply knowledge of, for example, anatomy in support of the newly reformed Lutheran society. Thus, the crown and the church officially sanctioned Melanchthon's thoughts on natural philosophy as a means to apprehend, first, the majestic glory of divine providence; second, that man was truly created and assigned his place by God; and third, that it was demanded of all men and women that they submit themselves to the will of God and the laws of the public authorities.

Shared written case formulations and weight change in outpatient therapy for anorexia nervosa: a naturalistic single case series.

PubMed

Gladwin, Alice M; Evangeli, Michael

2013-01-01

The therapeutic effects of written shared case formulations are underexplored and have not been examined in anorexia nervosa. This study explored the relationship between (a) the delivery (b) the quality of a shared written case formulation and weight in outpatient psychological therapy for anorexia nervosa. A naturalistic single case series approach was used to examine the case notes of women who had attended a specialist eating disorders service over a 2-year period. The case notes of 15 adult women who had undergone outpatient psychological therapy for anorexia nervosa with a shared written case formulation component were reviewed. The impact of the quality of the case formulation on weekly weight was examined for 14 of the clients where the case formulation was available. The nature of the relationship between the delivery of the written shared case formulation and weight was examined for all 15 clients. There was some evidence to support an association between delivery of the shared written case formulation and weight changes (both weight gain [five out of 15 clients] and weight loss [three out of 15 clients]) in individual cases. Higher case formulation quality was related to cases where weight change did not occur. The delivery of case formulations can be associated with important therapeutic change (both beneficial and potentially harmful) in anorexia nervosa. Future research into the causal mechanisms associated with sharing formulations will face the challenge of adopting strategies that allow for an in-depth exploration of complex therapy variables whilst overcoming methodological challenges. Copyright © 2012 John Wiley & Sons, Ltd.

A systematic review on nanoencapsulation of food bioactive ingredients and nutraceuticals by various nanocarriers.

PubMed

Assadpour, Elham; Jafari, Seid Mahdi

2018-06-08

Today, there is an ever-growing interest on natural food ingredients both by consumers and producers in the food industry. In fact, people are looking for those products in the market which are free from artificial and synthetic additives and can promote their health. These food bioactive ingredients should be formulated in such a way that protects them against harsh process and environmental conditions and safely could be delivered to the target organs and cells. Nanoencapsulation is a perfect strategy for this situation and there have been many studies in recent years for nanoencapsulation of food components and nutraceuticals by different technologies. In this review paper, our main goal is firstly to have an overview of nanoencapsulation techniques applicable to food ingredients in a systematic classification, i.e., lipid-based nanocarriers, nature-inspired nanocarriers, special-equipment-based nanocarriers, biopolymer nanocarriers, and other miscellaneous nanocarriers. Then, application of these cutting-edge nanocarriers for different nutraceuticals including phenolic compounds and antioxidants, natural food colorants, antimicrobial agents and essential oils, vitamins, minerals, flavors, fish oils and essential fatty acids will be discussed along with presenting some examples in each field.

On the Influence of Naturalism on American Literature

ERIC Educational Resources Information Center

Zhang, Xiaofen

2010-01-01

Naturalism was first proposed and formulated by French novelist Emile Zola, and it was introduced to America by American novelist Frank Norris. It is a new and harsher realism. It is a theory in literature emphasizing scientific observation of life without idealism or avoidance of the ugly. American literature naturalists dismissed the validity of…

The "natural" aversion: the FDA's reluctance to define a leading food-industry marketing claim, and the pressing need for a workable rule.

PubMed

Farris, April L

2010-01-01

As of 2009, the "natural foods" industry has become a 22.3 billion dollar giant and "all-natural" is the second-leading marketing claim for all new food products. Even in such a flourishing market, the Food and Drug Administration (FDA) has never defined the term "natural" through rulemaking. FDA and the U.S. Department of Agriculture (USDA) have instead created separate, non-identical policy statements governing the use of the term "natural," and FDA has abandoned efforts to define "natural" through rulemaking in the face of more pressing priorities. In absence of any governing federal standard, consumer advocacy groups and warring food industries have attempted to define "natural" to fit their preferences through high-stakes litigation of state law claims, leaving courts free to apply diverging standards without the expertise of FDA. Recent case law from federal district courts and the Supreme Court leaves little hope that FDA's current policy statement will preempt state law causes of action. To prevent a potential patchwork of definitions varying by state, and to create a legitimate standard resting on informed scientific expertise rather than consumer whims, FDA should engage in rulemaking to define the term "natural." This paper concludes by sketching potential formulations for such a rule based on FDA's previous successful rule-making ventures and standards used by natural foods retailers.

Liposomal Aloe vera trans-emulgel drug delivery of naproxen and nimesulide: A study

PubMed Central

Venkataharsha, Panuganti; Maheshwara, Ellutla; Raju, Y Prasanna; Reddy, Vayalpati Ashok; Rayadu, Bandugalla Sanjeev; Karisetty, Basappa

2015-01-01

Introduction: The present aim of this study was to formulate naproxen and nimesulide liposomal formulation for incorporation in Aloe vera transemulgel and to carry out in vitro and in vivo evaluation of the formulation. Material and Methods: A. vera gel was prepared and used as a gel base for formulation. Carbopol 934 is used as a gelling agent and Methyl paraben was used as a preservative for the formulation of the gel. Liposomes was formulated by using hydration method. The formulated naproxen and nimesulide liposomal formulation using A. vera trans-emul gel were evaluated for in vitro studies such as drug release, permeation study, and drug content and entrapment efficiency. Paw edema method in Wistar rats induced by carrageenan is used to study in vivo anti-inflammatory action. Result: From the in vitro studies such permeability drug release naproxen 65% (69.6), Nimesulide 65% (61.1), and commercial Nimsulide gel (60.82) at 240 min. In vivo data shows that formulated liposomal transemulgel formulation are superior in their efficacy compared to commercial and A. vera gel. The results are compared with the commercial formulations. Conclusion: From our results, it is concluded that the A. vera trans emul gel using nimesulide and naproxen liposomal formulation is stable and prepared gel base is effective for formulation with high drug release and drug content compared with commercial formulation with significant anti-inflammatory effect. PMID:25599030

In vivo skin effects of a dimethylaminoethanol (DMAE) based formulation.

PubMed

Tadini, K A; Campos, P M B G Maia

2009-12-01

Dimethylaminoethanol (DMAE) has been used in anti-aging formulations but few scientifically based data address its efficacy. The aim of this study was to evaluate the effects of DMAE-based formulations on hairless mice and human skin. Formulations containing with or without DMAE were applied to the dorsum of hairless mice. Histopathological and histometric evaluations were carried out after seven days. Formulations were also applied to the ventral forearm and the lateral periocular area of human volunteers. Stratum corneum water content and skin mechanical properties were analyzed using Corneometer and Cutometer, before and after a single and repeated application. Histometric evaluations showed that formulations with or without DMAE increased the viable epidermis thickness, but only the DMAE-supplemented formulation led to increased dermal thickness. DMAE also induced increase in collagen fiber thickness, which was observed in the histopathological study. After the single and the 8-week period application on human skin, formulations with and without DMAE enhanced the stratum corneum water content in the forearm skin. Mechanical properties were not significantly modified. So, we can suggest that DMAE action is related to its effects on the dermis as observed in the histopathological and histometric studies and showed hydration effects on skin.

Release behavior and bioefficacy of imazethapyr formulations based on biopolymeric hydrogels.

PubMed

Kumar, Vikas; Singh, Anupama; Das, T K; Sarkar, Dhruba Jyoti; Singh, Shashi Bala; Dhaka, Rashmi; Kumar, Anil

2017-06-03

Controlled release formulations of imazethapyr herbicide have been developed employing guar gum-g-cl-polyacrylate/bentonite clay hydrogel composite (GG-HG) and guar gum-g-cl-PNIPAm nano hydrogel (GG-NHG) as carriers, to assess the suitability of biopolymeric hydrogels as controlled herbicide release devices. The kinetics of imazethapyr release from the developed formulations was studied in water and it revealed that the developed formulations of imazethapyr behaved as slow release formulations as compared to commercial formulation. The calculated diffusion exponent (n) values showed that Fickian diffusion was the predominant mechanism of imazethapyr release from the developed formulations. Time for release of half of the loaded imazethapyr (t 1/2 ) ranged between 0.06 and 4.8 days in case of GG-NHG and 4.4 and 12.6 days for the GG-HG formulations. Weed control index (WCI) of GG-HG and GG-NHG formulations was similar to that of the commercial formulation and the herbicidal effect was observed for relatively longer period. Guar gum-based biopolymeric hydrogels in both macro and nano particle size range can serve as potential carriers in developing slow release herbicide formulations.

The artificial membrane insert system as predictive tool for formulation performance evaluation.

PubMed

Berben, Philippe; Brouwers, Joachim; Augustijns, Patrick

2018-02-15

In view of the increasing interest of pharmaceutical companies for cell- and tissue-free models to implement permeation into formulation testing, this study explored the capability of an artificial membrane insert system (AMI-system) as predictive tool to evaluate the performance of absorption-enabling formulations. Firstly, to explore the usefulness of the AMI-system in supersaturation assessment, permeation was monitored after induction of different degrees of loviride supersaturation. Secondly, to explore the usefulness of the AMI-system in formulation evaluation, a two-stage dissolution test was performed prior to permeation assessment. Different case examples were selected based on the availability of in vivo (intraluminal and systemic) data: (i) a suspension of posaconazole (Noxafil ® ), (ii) a cyclodextrin-based formulation of itraconazole (Sporanox ® ), and (iii) a micronized (Lipanthyl ® ) and nanosized (Lipanthylnano ® ) formulation of fenofibrate. The obtained results demonstrate that the AMI-system is able to capture the impact of loviride supersaturation on permeation. Furthermore, the AMI-system correctly predicted the effects of (i) formulation pH on posaconazole absorption, (ii) dilution on cyclodextrin-based itraconazole absorption, and (iii) food intake on fenofibrate absorption. Based on the applied in vivo/in vitro approach, the AMI-system combined with simple dissolution testing appears to be a time- and cost-effective tool for the early-stage evaluation of absorption-enabling formulations. Copyright © 2017 Elsevier B.V. All rights reserved.

Case formulation and management using pattern-based formulation (PBF) methodology: clinical case 1.

PubMed

Fernando, Irosh; Cohen, Martin

2014-02-01

A tool for psychiatric case formulation known as pattern-based formulation (PBF) has been recently introduced. This paper presents an application of this methodology in formulating and managing complex clinical cases. The symptomatology of the clinical presentation has been parsed into individual clinical phenomena and interpreted by selecting explanatory models. The clinical presentation demonstrates how PBF has been used as a clinical tool to guide clinicians' thinking, that takes a structured approach to manage multiple issues using a broad range of management strategies. In doing so, the paper also introduces a number of patterns related to the observed clinical phenomena that can be re-used as explanatory models when formulating other clinical cases. It is expected that this paper will assist clinicians, and particularly trainees, to better understand PBF methodology and apply it to improve their formulation skills.

Effects of different diets on the dietary attractability and selectivity of Chinese shrimp, Fenneropenaeus chinensis

NASA Astrophysics Data System (ADS)

Huang, Guoqiang; Dong, Shuanglin; Wang, Fang

2005-01-01

Attractabilities of different diets and dietary selectivity of Chinese shrimp, Fenneropenaeus chinensis were studied through behavior observation and feeding experiment, respectively. The five diets used in the experiment are: Fish Flesh (FF), Shrimp Flesh (SF), Clam Foot (CF), Polychaete Worm (PW), and Formulated Diet (FD). No significant differences of attractability exist between any two different diets when every two natural diets or all five diets are provided simultaneously. On the other hand, significant differences of attractability exist between FD and every single natural diet when they are provided simultaneously. Results of behavioral observation indicate that natural diets are more attractive than FD. In feeding experiment, Chinese shrimp has distinct selectivity on different diets. It positively selects CF and PW, negatively selects FF and SF, and excludes FD absolutely. The results of the present studies indicate that the dietary selectivity of shrimp was based not only on the attractabilities of the diets, but also on the responses such as growth and food conversion.

Vibration of a spatial elastica constrained inside a straight tube

NASA Astrophysics Data System (ADS)

Chen, Jen-San; Fang, Joyce

2014-04-01

In this paper we study the dynamic behavior of a clamped-clamped spatial elastica under edge thrust constrained inside a straight cylindrical tube. Attention is focused on the calculation of the natural frequencies and mode shapes of the planar and spatial one-point-contact deformations. The main issue in determining the natural frequencies of a constrained rod is the movement of the contact point during vibration. In order to capture the physical essence of the contact-point movement, an Eulerian description of the equations of motion based on director theory is formulated. After proper linearization of the equations of motion, boundary conditions, and contact conditions, the natural frequencies and mode shapes of the elastica can be obtained by solving a system of eighteen first-order differential equations with shooting method. It is concluded that the planar one-point-contact deformation becomes unstable and evolves to a spatial deformation at a bifurcation point in both displacement and force control procedures.

An Image Processing Algorithm Based On FMAT

NASA Technical Reports Server (NTRS)

Wang, Lui; Pal, Sankar K.

1995-01-01

Information deleted in ways minimizing adverse effects on reconstructed images. New grey-scale generalization of medial axis transformation (MAT), called FMAT (short for Fuzzy MAT) proposed. Formulated by making natural extension to fuzzy-set theory of all definitions and conditions (e.g., characteristic function of disk, subset condition of disk, and redundancy checking) used in defining MAT of crisp set. Does not need image to have any kind of priori segmentation, and allows medial axis (and skeleton) to be fuzzy subset of input image. Resulting FMAT (consisting of maximal fuzzy disks) capable of reconstructing exactly original image.

Manifolds for pose tracking from monocular video

NASA Astrophysics Data System (ADS)

Basu, Saurav; Poulin, Joshua; Acton, Scott T.

2015-03-01

We formulate a simple human-pose tracking theory from monocular video based on the fundamental relationship between changes in pose and image motion vectors. We investigate the natural embedding of the low-dimensional body pose space into a high-dimensional space of body configurations that behaves locally in a linear manner. The embedded manifold facilitates the decomposition of the image motion vectors into basis motion vector fields of the tangent space to the manifold. This approach benefits from the style invariance of image motion flow vectors, and experiments to validate the fundamental theory show reasonable accuracy (within 4.9 deg of the ground truth).

Scopus: A system for the evaluation of scientific journals

NASA Astrophysics Data System (ADS)

Guz, A. N.; Rushchitsky, J. J.

2009-04-01

The paper discusses the evaluation of scientific journals based on the Scopus database, information tools, and criteria. The SJR (SCImago Journal Rank) as the main criterion used by Scopus to evaluate scientific journals is considered. The Scopus and ISI systems are compared using information on the journal Prikladnaya Mekhanika ( International Applied Mechanics), a number of world-known journals on mechanics, and some journals on natural sciences issued by the National Academy of Sciences of Ukraine. Some comments and proposals are formulated. This paper may be considered as a follow up on papers published in Prikladnaya Mekhanika ( International Applied Mechanics) in 2005-2009

Development of carrier-based formulation of root endophyte Piriformospora indica and its evaluation on Phaseolus vulgaris L.

PubMed

Tripathi, Swati; Das, Aparajita; Chandra, Anil; Varma, Ajit

2015-02-01

Endophytic fungi are plant beneficial rhizospheric microorganisms often applied as bioinoculants for enhanced and disease-free crop production. The objectives of the present work were to develop a carrier-based formulation of root endophyte Piriformospora indica as a bioinoculant. Powder formulation of four different carrier materials viz., talcum powder, clay, sawdust and bioboost (organic supplement) were evaluated and a talc-based formulation was optimized for a longer shelf life with respect to microbial concentration, storage temperature and biological activity. Finally the effect of optimized talc formulation on plant productivity was determined. The application dosages were optimized by studies on plant growth parameters of Phaseolus vulgaris L. plants under green house conditions. Five percent formulation (w/w) of talcum powder was observed to be the most stable at 30 °C with 10(8) CFU g(-1) and effective for a storage period of 6 months. The application of this optimized formulation resulted in increase of growth parameters of P. vulgaris L. and better adaptation of plants under green house conditions.

Microsphere based improved sunscreen formulation of ethylhexyl methoxycinnamate.

PubMed

Gogna, Deepak; Jain, Sunil K; Yadav, Awesh K; Agrawal, G P

2007-04-01

Polymethylmethacrylate (PMMA) microspheres of ethylhexyl methoxycinnamate (EHM) were prepared by emulsion solvent evaporation method to improve its photostability and effectiveness as sunscreening agent. Process parameters like stirring speed and aqueous polyvinyl alcohol (PVA) concentration were analyzed in order to optimize the formulations. Shape and surface morphology of the microspheres were examined using scanning electron microscopy. Particle size of the microspheres was determined using laser diffraction particle size analyzer. The PMMA microspheres of EHM were incorporated in water-removable cream base. The in vitro drug release of EHM in pH 7.4 was performed using dialysis membrane. Thin layer chromatography was performed to determine photostability of EHM inside the microspheres. The formulations were evaluated for sun protection factor (SPF) and minimum erythema dose (MED) in albino rats. Cream base formulation containing microspheres prepared using EHM:PMMA in ratio of 1:3 (C(3)) showed slowest drug (EHM) release and those prepared with EHM: PMMA in ratio of 1:1 showed fastest release. The cream base formulations containing EHM loaded microspheres had shown better SPF (more than 16.0) as compared to formulation C(d) that contained 3% free EHM as sunscreen agent and showed SPF 4.66. These studies revealed that the incorporation of EHM loaded PMMA microspheres into cream base had greatly increased the efficacy of sunscreen formulation approximately four times. Further, photostability was also shown to be improved in PMMA microspheres.

Mechanical Properties of Graphene-Rubber Nanocomposites

NASA Astrophysics Data System (ADS)

Anhar, N. A. M.; Ramli, M. M.; Hambali, N. A. M. A.; Aziz, A. A.; Mat Isa, S. S.; Danial, N. S.; Abdullah, M. M. A. B.

2017-11-01

This research focused on development of wearable sensor device by using Prevulcanized Natural Rubber (PV) and Epoxidized Natural Rubber (ENR 50) latex incorporated with graphene oxide (GO), graphene paste, graphene powder and reduced graphene oxide (rGO) powder. The compounding formulation and calculation were based on phr (parts per hundred rubber) and all the samples were then tested for mechanical properties using Instron 5565 machine. It was found that the sonication effects on tensile strength may have better quality of tensile strength compared to non-sonicated GO. For PV incorporate GO, the optimum loading was best determined at loading 1.5 phr with or without sonication and similar result was recorded for PV/G. For ENR 50 incorporate graphene paste and rGO powder nanocomposite shows the best optimum was at 3.0 phr with 24 hours’ sonication.

Passivated iodine pentoxide oxidizer for potential biocidal nanoenergetic applications.

PubMed

Feng, Jingyu; Jian, Guoqiang; Liu, Qing; Zachariah, Michael R

2013-09-25

Iodine pentoxide (I2O5), also known as diiodine pentoxide, is a strong oxidizer which has been recently proposed as an iodine-rich oxidizer in nanoenergetic formulations, whose combustion products lead to molecular iodine as a biocidal agent. However, its highly hygroscopic nature hinders its performance as a strong oxidizer and an iodine releasing agent and prevents its implementation. In this work, we developed a gas phase assisted aerosol spray pyrolysis which enables creation of iron oxide passivated I2O5. Transmission electron microscopy elemental imaging as well as temperature-jump mass spectrometry confirmed the core shell nature of the material and the fact that I2O5 could be encapsulated in pure unhydrated form. Combustion performance finds an optimal coating thickness that enables combustion performance similar to a high performing CuO based thermite.

Bacterial proliferation on clay nanotube Pickering emulsions for oil spill bioremediation.

PubMed

Panchal, Abhishek; Swientoniewski, Lauren T; Omarova, Marzhana; Yu, Tianyi; Zhang, Donghui; Blake, Diane A; John, Vijay; Lvov, Yuri M

2018-04-01

Halloysites (tubular aluminosilicate) are introduced as inexpensive natural nanoparticles that form and stabilize oil-water emulsions. Pickering emulsification can proceed with energies low enough to be afforded by ocean turbulence and the stability of droplets extends over more than a week. The oil/water interface is shown to be roughened and bacteria, which are added for oil degradation, are better attached to such oil droplets than to droplets without halloysites. The metabolic activity of Alcanivorax borkumensis, alkanotrophic bacteria widely distributed in marine environments, is enhanced by halloysite addition. A halloysite-based dispersant system is therefore environmentally friendly and promising for further optimization. The key elements of the described formulations are natural clay nanotubes, which are abundantly available in thousands of tons, thus making this technology scalable for environmental remediation. Copyright © 2018 Elsevier B.V. All rights reserved.

Life Origination Hydrate Hypothesis (LOH-Hypothesis)

PubMed Central

Ostrovskii, Victor; Kadyshevich, Elena

2012-01-01

The paper develops the Life Origination Hydrate Hypothesis (LOH-hypothesis), according to which living-matter simplest elements (LMSEs, which are N-bases, riboses, nucleosides, nucleotides), DNA- and RNA-like molecules, amino-acids, and proto-cells repeatedly originated on the basis of thermodynamically controlled, natural, and inevitable processes governed by universal physical and chemical laws from CH4, niters, and phosphates under the Earth's surface or seabed within the crystal cavities of the honeycomb methane-hydrate structure at low temperatures; the chemical processes passed slowly through all successive chemical steps in the direction that is determined by a gradual decrease in the Gibbs free energy of reacting systems. The hypothesis formulation method is based on the thermodynamic directedness of natural movement and consists ofan attempt to mentally backtrack on the progression of nature and thus reveal principal milestones alongits route. The changes in Gibbs free energy are estimated for different steps of the living-matter origination process; special attention is paid to the processes of proto-cell formation. Just the occurrence of the gas-hydrate periodic honeycomb matrix filled with LMSEs almost completely in its final state accounts for size limitation in the DNA functional groups and the nonrandom location of N-bases in the DNA chains. The slowness of the low-temperature chemical transformations and their “thermodynamic front” guide the gross process of living matter origination and its successive steps. It is shown that the hypothesis is thermodynamically justified and testable and that many observed natural phenomena count in its favor. PMID:25382120

A renaissance of soaps? - How to make clear and stable solutions at neutral pH and room temperature.

PubMed

Wolfrum, Stefan; Marcus, Julien; Touraud, Didier; Kunz, Werner

2016-10-01

Soaps are the oldest and perhaps most natural surfactants. However, they lost much of their importance since "technical surfactants", usually based on sulfates or sulfonates, have been developed over the last fifty years. Indeed, soaps are pH- and salt-sensitive and they are irritant, especially to the eyes. In food emulsions, although authorized, they have a bad taste, and long-chain saturated soaps have a high Krafft temperature. We believe that most or perhaps all of these problems can be solved with modern formulation approaches. We start this paper with a short overview of our present knowledge of soaps and soap formulations. Then we focus on the problem of the lacking soap solubility at neutral pH values. For example, it is well known that with the food emulsifier sodium oleate (NaOl), clear and stable aqueous solutions can only be obtained at pH values higher than 10. A decrease in the pH value leads to turbid and unstable solutions. This effect is not compatible with the formulation of aqueous stable and drinkable formulations with neutral or even acidic pH values. However, the pH value/phase behavior of aqueous soap solutions can be altered by the addition of other surfactants. Such a surfactant can be Rebaudioside A (RebA), a steviol glycoside from the plant Stevia rebaudiana which is used as a natural food sweetener. In a recent paper, we showed the influence of RebA on the apKa value of sodium oleate in a beverage microemulsion and on its clearing temperature. In the present paper, we report on the effect of the edible bio-surfactant RebA, on the macroscopic and microscopic phase behavior of simple aqueous sodium oleate solutions at varying pH values. The macroscopic phase behavior is investigated by visual observation and turbidity measurements. The microscopic phase behavior is analyzed by acid-base titration curves, phase-contrast and electron microscopy. It turned out that even at neutral pH, aqueous NaOl/RebA solutions can be completely clear and stable for more than 50days at room temperature. This is for the first time that a long chain soap could be really solubilized in water at neutral pH at room temperature. At last, these findings were applied to prepare stable, highly translucent and drinkable aqueous solutions of omega-3-fatty acids at a pH value of 7.5. Copyright © 2016 Elsevier B.V. All rights reserved.

Physico-mechanical properties of plywood bonded with ecological adhesives from Acacia mollissima tannins and lignosulfonates

NASA Astrophysics Data System (ADS)

Rhazi, Naima; Oumam, Mina; Sesbou, Abdessadek; Hannache, Hassan; Charrier-El Bouhtoury, Fatima

2017-06-01

The objective of this research was to develop ecological adhesives for bonding plywood panels using lignosulfonates, a common waste product of the wood pulp industry, and natural tannin extracted from Moroccan bark of Acacia mollissima using different process. Natural tannin and lignin were used in wood adhesives formulation to substitute resins based on phenol and formaldehyde. To achieve this, the lignosulfonates were glyoxalated to enhance their reactivity and the used tannins obtained by three different extraction methods were compared with commercial mimosa tannin. The proportion of Acacia mollissima tannins and lignosulfonates, the pressing time, the pressing temperature, and the pressure used were studied to improve mechanical properties, and bonding quality of plywood panel. The properties of plywood panels produced with these adhesives were tested in accordance with normative tests. Thus, the tensile strength, and the shear strength were measured. The results showed that the performance of the plywood panels made using biobased tannin adhesives was influenced by physical conditions such as pressure, press temperature as well as by chemical conditions, such as the tannin-lignin ratio. It exhibited excellent mechanical properties comparable to commercially available phenol-formaldehyde plywood adhesives. This study showed that biobased adhesives formulations presented good and higher mechanical performance and no formaldehyde emission. Contribution to the topical issue "Materials for Energy harvesting, conversion and storage II (ICOME 2016)", edited by Jean-Michel Nunzi, Rachid Bennacer and Mohammed El Ganaoui

Effect of organized assemblies. Part 4. Formulation of highly concentrated coal-water slurry using a natural surfactant

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

Debadutta Das; Sagarika Panigrahi; Pramila K. Misra

2008-05-15

Coal-water slurry has received considerable research nowadays due to its ability in substituting energy sources. The present work reports the formulation of highly concentrated coal-water slurry using a natural occurring surface active compound, saponin, extracted from the fruits of plant Sapindous laurifolia. The isolation of saponin from the plant and its surface activity has been discussed. The rheological characteristics of coal-water slurry have been investigated as a function of coal loading, ash content of coal, pH, temperature, and amount of saponin. The viscosity of the slurry and zeta potential are substantially decreased with concomitant shift of the isoelectric point ofmore » coal on adsorption of saponin to it. In the presence of 0.8% of saponin, coal-water slurry containing 64% weight fraction of coal could be achieved. The slurry is stable for a period of as long as 1 month in contrast to 4-5 h in the case of bare coal-water slurry. The results confirm the use of saponin as a suitable additive for coal-water slurry similar to the commercially available additive such as sodium dodecyl sulfate. Basing on the effect of pH on the zeta potential and viscosity of slurry, a suitable mechanism for saponin-coal interaction and orientation of saponin at the coal-water interface has been proposed. 47 refs., 12 figs., 5 tabs.« less

Melt processed crystalline ceramic waste forms for advanced nuclear fuel cycles: CRP T21027 1813: Processing technologies for high level waste, formulation of matrices and characterization of waste forms, task 17208: Final report

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

Amoroso, J. W.; Marra, J. C.

2015-08-26

A multi-phase ceramic waste form is being developed at the Savannah River National Laboratory (SRNL) for treatment of secondary waste streams generated by reprocessing commercial spent nuclear. The envisioned waste stream contains a mixture of transition, alkali, alkaline earth, and lanthanide metals. Ceramic waste forms are tailored (engineered) to incorporate waste components as part of their crystal structure based on knowledge from naturally found minerals containing radioactive and non-radioactive species similar to the radionuclides of concern in wastes from fuel reprocessing. The ability to tailor ceramics to mimic naturally occurring crystals substantiates the long term stability of such crystals (ceramics)more » over geologic timescales of interest for nuclear waste immobilization [1]. A durable multi-phase ceramic waste form tailored to incorporate all the waste components has the potential to broaden the available disposal options and thus minimize the storage and disposal costs associated with aqueous reprocessing. This report summarizes results from three years of work on the IAEA Coordinated Research Project on “Processing technologies for high level waste, formulation of matrices and characterization of waste forms” (T21027), and specific task “Melt Processed Crystalline Ceramic Waste Forms for Advanced Nuclear Fuel Cycles” (17208).« less

Melt processed crystalline ceramic waste forms for advanced nuclear fuel cycles: CRP T21027 1813: Processing technologies for high level waste, formulation of matrices and characterization of waste forms, Task 17208: Final report

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

Amoroso, J. W.; Marra, J. C.

2015-08-26

A multi-phase ceramic waste form is being developed at the Savannah River National Laboratory (SRNL) for treatment of secondary waste streams generated by reprocessing commercial spent nuclear. The envisioned waste stream contains a mixture of transition, alkali, alkaline earth, and lanthanide metals. Ceramic waste forms are tailored (engineered) to incorporate waste components as part of their crystal structure based on knowledge from naturally found minerals containing radioactive and non-radioactive species similar to the radionuclides of concern in wastes from fuel reprocessing. The ability to tailor ceramics to mimic naturally occurring crystals substantiates the long term stability of such crystals (ceramics)more » over geologic timescales of interest for nuclear waste immobilization [1]. A durable multi-phase ceramic waste form tailored to incorporate all the waste components has the potential to broaden the available disposal options and thus minimize the storage and disposal costs associated with aqueous reprocessing. This report summarizes results from three years of work on the IAEA Coordinated Research Project on “Processing technologies for high level waste, formulation of matrices and characterization of waste forms” (T21027), and specific task “Melt Processed Crystalline Ceramic Waste Forms for Advanced Nuclear Fuel Cycles” (17208).« less

Lipid Nanoparticles: A novel approach for brain targeting.

PubMed

Shankar, Ravi; Joshi, Monika; Pathak, Kamla

2018-06-10

Brain is a delicate organ, separated from general circulation and is characterized by the presence of relatively impermeable Blood Brain Barrier (BBB). The BBB maintains homeostasis in the brain thus restricting the entrance of foreign bodies and several molecules from reaching the brain. As a result several promising molecules do not reach the target site and fail to produce in vivo response. Nevertheless, lipid nanoparticles are taken up readily by the brain because of their lipophilic nature. The bioacceptable and biodegradable nature of lipid nanoparticles makes them less toxic and suited for brain targeting. In the present review the BBB, mechanism of transport across the BBB, strategies to bypass the blood-brain barrier have been presented. The aptness of lipid nanoparticles for brain targeting has been highlighted. The proposed mechanism of uptake of the lipid nanoparticles, methods of prolonging the plasma retention and various methods of preparation for formulation of effective delivery systems for brain targeting have been included and dealt in this review. Lipid based formulations can be designated as the current and future generation of drug delivery systems as these possess tremendous potential to bypass BBB and reach the target site due to their small size and ability to dodge the reticular endothelial system. However, these nanostructures need to be investigated intensively to successfully reach the clinical trials stage. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

A comparison between rate-and-state friction and microphysical models, based on numerical simulations of fault slip

NASA Astrophysics Data System (ADS)

van den Ende, M. P. A.; Chen, J.; Ampuero, J.-P.; Niemeijer, A. R.

2018-05-01

Rate-and-state friction (RSF) is commonly used for the characterisation of laboratory friction experiments, such as velocity-step tests. However, the RSF framework provides little physical basis for the extrapolation of these results to the scales and conditions of natural fault systems, and so open questions remain regarding the applicability of the experimentally obtained RSF parameters for predicting seismic cycle transients. As an alternative to classical RSF, microphysics-based models offer means for interpreting laboratory and field observations, but are generally over-simplified with respect to heterogeneous natural systems. In order to bridge the temporal and spatial gap between the laboratory and nature, we have implemented existing microphysical model formulations into an earthquake cycle simulator. Through this numerical framework, we make a direct comparison between simulations exhibiting RSF-controlled fault rheology, and simulations in which the fault rheology is dictated by the microphysical model. Even though the input parameters for the RSF simulation are directly derived from the microphysical model, the microphysics-based simulations produce significantly smaller seismic event sizes than the RSF-based simulation, and suggest a more stable fault slip behaviour. Our results reveal fundamental limitations in using classical rate-and-state friction for the extrapolation of laboratory results. The microphysics-based approach offers a more complete framework in this respect, and may be used for a more detailed study of the seismic cycle in relation to material properties and fault zone pressure-temperature conditions.

Peptaibol, secondary-metabolite, and hydrophobin pattern of commercial biocontrol agents formulated with species of the Trichoderma harzianum complex.

PubMed

Degenkolb, Thomas; Fog Nielsen, Kristian; Dieckmann, Ralf; Branco-Rocha, Fabiano; Chaverri, Priscila; Samuels, Gary J; Thrane, Ulf; von Döhren, Hans; Vilcinskas, Andreas; Brückner, Hans

2015-04-01

The production of bioactive polypeptides (peptaibiotics) in vivo is a sophisticated adaptation strategy of both mycoparasitic and saprotrophic Trichoderma species for colonizing and defending their natural habitats. This feature is of major practical importance, as the detection of peptaibiotics in plant-protective Trichoderma species, which are successfully used against economically relevant bacterial and fungal plant pathogens, certainly contributes to a better understanding of these complex antagonistic interactions. We analyzed five commercial biocontrol agents (BCAs), namely Canna(®) , Trichosan(®) , Vitalin(®) , Promot(®) WP, and TrichoMax(®) , formulated with recently described species of the Trichoderma harzianum complex, viz. T. afroharzianum, T. simmonsii, and T. guizhouense. By using the well-established, HPLC/MS-based peptaibiomics approach, it could unequivocally be demonstrated that all of these formulations contained new and recurrent peptaibols, i.e., peptaibiotics carrying an acetylated N-terminus, the C-terminus of which is reduced to a 1,2-amino alcohol. Their chain lengths, including the amino alcohol, were 11, 14, and 18 residues, respectively. Peptaibols were also to be the dominating secondary metabolites in plate cultures of the four strains obtained from four of the Trichoderma- based BCAs, contributing 95% of the UHPLC-UV/VIS peak areas and 99% of the total ion count MS peak area from solid media. Furthermore, species-specific hydrophobins, as well as non-peptaibiotic secondary metabolites, were detected, the latter being known for their antifungal, siderophore, or plant-growth-promoting activities. Notably, none of the isolates produced low-molecular weight mycotoxins. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

Characterisation of protein stability in rod-insert vaginal rings.

PubMed

Pattani, Aditya; Lowry, Deborah; Curran, Rhonda M; McGrath, Stephanie; Kett, Vicky L; Andrews, Gavin P; Malcolm, R Karl

2012-07-01

A major goal in vaccine development is elimination of the 'cold chain', the transport and storage system for maintenance and distribution of the vaccine product. This is particularly pertinent to liquid formulation of vaccines. We have previously described the rod-insert vaginal ring (RiR) device, comprising an elastomeric body into which are inserted lyophilised, rod-shaped, solid drug dosage forms, and having potential for sustained mucosal delivery of biomacromolecules, such as HIV envelope protein-based vaccine candidates. Given the solid, lyophilised nature of these insert dosage forms, we hypothesised that antigen stability may be significantly increased compared with more conventional solubilised vaginal gel format. In this study, we prepared and tested vaginal ring devices fitted with lyophilised rod inserts containing the model antigen bovine serum albumin (BSA). Both the RiRs and the gels that were freeze-dried to prepare the inserts were evaluated for BSA stability using PAGE, turbidimetry, microbial load, MALDI-TOF and qualitative precipitate solubility measurements. When stored at 4 °C, but not when stored at 40 °C/75% RH, the RiR formulation offered protection against structural and conformational changes to BSA. The insert also retained matrix integrity and release characteristics. The results demonstrate that lypophilised gels can provide relative protection against degradation at lower temperatures compared to semi-solid gels. The major mechanism of degradation at 40 °C/75% RH was shown to be protein aggregation. Finally, in a preliminary study, we found that addition of trehalose to the formulation significantly reduces the rate of BSA degradation compared to the original formulation when stored at 40 °C/75% RH. Establishing the mechanism of degradation, and finding that degradation is decelerated in the presence of trehalose, will help inform further development of RiRs specifically and polymer based freeze-dried systems in general. Copyright © 2012 Elsevier B.V. All rights reserved.

Beyond Yellow Curry: Assessing Commercial Curcumin Absorption Technologies

PubMed Central

Douglass, Brad J.; Clouatre, Dallas L.

2015-01-01

BACKGROUND: Few natural products have demonstrated the range of protective and therapeutic promise as have turmeric and its principal bioactive components: curcumin, demethoxycurcumin, and bisdemethoxycurcumin. Success in translating this potential into tangible benefits has been limited by inherently poor intestinal absorption, rapid metabolism, and limited systemic bioavailability. Seeking to overcome these limitations, food ingredient formulators have begun to employ a variety of approaches to enhance absorption and bioactivity. Many of these strategies improve upon the age-old practice of consuming turmeric in fat-based sauces, such as in a fat-rich yellow curry. However, there exists uncertainty as to how the various commercially available offerings compare to each other in terms of either uptake or efficacy, and this uncertainty leaves physicians and nutritionists with a dearth of data for making recommendations to interested patients and consumers. Further complicating the issue are recent data suggesting that formulation strategies may not equally enhance the absorption of individual curcuminoids, a significant issue in that these curcuminoids exhibit somewhat different physiologic properties. OBJECTIVE: This review introduces needed order to the curcumin marketplace by examining bioavailability studies on a number of commercial curcumin ingredients and evaluating them on a level playing field. METHODS: The comparative analysis includes standard pharmacokinetic parameters and a new metric, relative mass efficiency (E). Relative mass efficiency allows for the comparison of different formulations even in cases in which the weight percentage of curcuminoids is vastly different. RESULTS: A hydrophilic carrier dispersed curcuminoid formula exhibits 45.9 times the bioavailability of the standard purified 95 percent curcuminoid preparation and, based on relative mass efficiency, 1.5 times the bioavailability of the next best commercial ingredient, a cyclodextrin complex. CONCLUSIONS: Delivery strategies can significantly improve the bioavailability of curcuminoids. Total formula mass is important for making practical formulation decisions about dosing, cost and space. PMID:25856323

The maximum work principle regarded as a consequence of an optimization problem based on mechanical virtual power principle and application of constructal theory

NASA Astrophysics Data System (ADS)

Gavrus, Adinel

2017-10-01

This scientific paper proposes to prove that the maximum work principle used by theory of continuum media plasticity can be regarded as a consequence of an optimization problem based on constructal theory (prof. Adrian BEJAN). It is known that the thermodynamics define the conservation of energy and the irreversibility of natural systems evolution. From mechanical point of view the first one permits to define the momentum balance equation, respectively the virtual power principle while the second one explains the tendency of all currents to flow from high to low values. According to the constructal law all finite-size system searches to evolve in such configurations that flow more and more easily over time distributing the imperfections in order to maximize entropy and to minimize the losses or dissipations. During a material forming process the application of constructal theory principles leads to the conclusion that under external loads the material flow is that which all dissipated mechanical power (deformation and friction) become minimal. On a mechanical point of view it is then possible to formulate the real state of all mechanical variables (stress, strain, strain rate) as those that minimize the total dissipated power. So between all other virtual non-equilibrium states, the real state minimizes the total dissipated power. It can be then obtained a variational minimization problem and this paper proof in a mathematical sense that starting from this formulation can be finding in a more general form the maximum work principle together with an equivalent form for the friction term. An application in the case of a plane compression of a plastic material shows the feasibility of the proposed minimization problem formulation to find analytical solution for both cases: one without friction influence and a second which take into account Tresca friction law. To valid the proposed formulation, a comparison with a classical analytical analysis based on slices, upper/lower bound methods and numerical Finite Element simulation is also presented.

Tolerance of entomopathogenic fungi to ultraviolet radiation: a review on screening of strains and their formulation.

PubMed

Fernandes, Éverton K K; Rangel, Drauzio E N; Braga, Gilberto U L; Roberts, Donald W

2015-08-01

Ultraviolet radiation from sunlight is probably the most detrimental environmental factor affecting the viability of entomopathogenic fungi applied to solar-exposed sites (e.g., leaves) for pest control. Most entomopathogenic fungi are sensitive to UV radiation, but there is great inter- and intraspecies variability in susceptibility to UV. This variability may reflect natural adaptations of isolates to their different environmental conditions. Selecting strains with outstanding natural tolerance to UV is considered as an important step to identify promising biological control agents. However, reports on tolerance among the isolates used to date must be analyzed carefully due to considerable variations in the methods used to garner the data. The current review presents tables listing many studies in which different methods were applied to check natural and enhanced tolerance to UV stress of numerous entomopathogenic fungi, including several well-known isolates of these fungi. The assessment of UV tolerance is usually conducted with conidia using dose-response methods, wherein the UV dose is calculated simply by multiplying the total irradiance by the period (time) of exposure. Although irradiation from lamps seldom presents an environmentally realistic spectral distribution, laboratory tests circumvent the uncontrollable circumstances associated with field assays. Most attempts to increase field persistence of microbial agents have included formulating conidia with UV protectants; however, in many cases, field efficacy of formulated fungi is still not fully adequate for dependable pest control.

Mesoporous silica-based dosage forms improve bioavailability of poorly soluble drugs in pigs: case example fenofibrate.

PubMed

O'Shea, Joseph P; Nagarsekar, Kalpa; Wieber, Alena; Witt, Vanessa; Herbert, Elisabeth; O'Driscoll, Caitriona M; Saal, Christoph; Lubda, Dieter; Griffin, Brendan T; Dressman, Jennifer B

2017-10-01

Mesoporous silicas (SLC) have demonstrated considerable potential to improve bioavailability of poorly soluble drugs by facilitating rapid dissolution and generating supersaturation. The addition of certain polymers can further enhance the dissolution of these formulations by preventing drug precipitation. This study uses fenofibrate as a model drug to investigate the performance of an SLC-based formulation, delivered with hydroxypropyl methylcellulose acetate succinate (HPMCAS) as a precipitation inhibitor, in pigs. The ability of biorelevant dissolution testing to predict the in vivo performance was also assessed. Fenofibrate-loaded mesoporous silica (FF-SLC), together with HPMCAS, displayed significant improvements in biorelevant dissolution tests relative to a reference formulation consisting of a physical mixture of crystalline fenofibrate with HPMCAS. In vivo assessment in fasted pigs demonstrated bioavailabilities of 86.69 ± 35.37% with combination of FF-SLC and HPMCAS in capsule form and 75.47 ± 14.58% as a suspension, compared to 19.92 ± 9.89% with the reference formulation. A positive correlation was identified between bioavailability and dissolution efficiency. The substantial improvements in bioavailability of fenofibrate from the SLC-based formulations confirm the ability of this formulation strategy to overcome the dissolution and solubility limitations, further raising the prospects of a future commercially available SLC-based formulation. © 2017 Royal Pharmaceutical Society.

Displaced path integral formulation for the momentum distribution of quantum particles.

PubMed

Lin, Lin; Morrone, Joseph A; Car, Roberto; Parrinello, Michele

2010-09-10

The proton momentum distribution, accessible by deep inelastic neutron scattering, is a very sensitive probe of the potential of mean force experienced by the protons in hydrogen-bonded systems. In this work we introduce a novel estimator for the end-to-end distribution of the Feynman paths, i.e., the Fourier transform of the momentum distribution. In this formulation, free particle and environmental contributions factorize. Moreover, the environmental contribution has a natural analogy to a free energy surface in statistical mechanics, facilitating the interpretation of experiments. The new formulation is not only conceptually but also computationally advantageous. We illustrate the method with applications to an empirical water model, ab initio ice, and one dimensional model systems.

Water hyacinth: a possible alternative rate retarding natural polymer used in sustained release tablet design

PubMed Central

Khatun, Sabera; Sutradhar, Kumar B.

2014-01-01

In recent years natural polymers have been widely used because of their effectiveness and availability over synthetic polymers. In this present investigation matrix tablets of Metformin hydrochloride were formulated using Water hyacinth powder and its rate retardant activity was studied. Tablets were prepared using wet granulation method with 8% starch as granulating agent and 5, 10, 15, 20, 25 and 30% of Water hyacinth powder to the drug. In preformulation study, angle of repose, Carr's Index and Hausner ratio were calculated. Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM) studies were performed and no interactions were found between drug and excipients. Weight variation, friability, hardness, thickness, diameter, and in vitro release study were performed with the prepared matrix tablets. Dissolution studies were conducted using USP type II apparatus at a speed of 100 rpm at 37°C ± 0.5 temperature for 8 h. Though all the formulations comply with both BP and USP requirements, formulation F-1 (5% of Water hyacinth) was the best fitted formula. The drug release patterns were explained in different kinetic models such as Zero order, First order, Higuchi, Hixson Crowell, and Korsmeyer-Peppas equations. The current investigation implies that Water hyacinth has the potential to be used as a rate-retarding agent in sustained release drug formulations. PMID:24966835

Assessment of antifungal activity of herbal and conventional toothpastes against clinical isolates of Candida albicans.

PubMed

Adwan, Ghaleb; Salameh, Yousef; Adwan, Kamel; Barakat, Ali

2012-05-01

To detect the anticandidal activity of nine toothpastes containing sodium fluoride, sodium monofluorophosphate and herbal extracts as an active ingredients against 45 oral and non oral Candida albicans (C. albicans) isolates. The antifungal activity of these toothpaste formulations was determined using a standard agar well diffusion method. Statistical analysis was performed using a statistical package, SPSS windows version 15, by applying mean values using one-way ANOVA with post-hoc least square differences (LSD) method. A P value of less than 0.05 was considered significant. All toothpastes studied in our experiments were effective in inhibiting the growth of all C. albicans isolates. The highest anticandidal activity was obtained from toothpaste that containing both herbal extracts and sodium fluoride as active ingredients, while the lowest activity was obtained from toothpaste containing sodium monofluorophosphate as an active ingredient. Antifungal activity of Parodontax toothpaste showed a significant difference (P< 0.001) against C. albicans isolates compared to toothpastes containing sodium fluoride or herbal products. In the present study, it has been demonstrated that toothpaste containing both herbal extracts and sodium fluoride as active ingredients are more effective in control of C. albicans, while toothpaste that containing monofluorophosphate as an active ingredient is less effective against C. albicans. Some herbal toothpaste formulations studied in our experiments, appear to be equally effective as the fluoride dental formulations and it can be used as an alternative to conventional formulations for individuals who have an interest in naturally-based products. Our results may provide invaluable information for dental professionals.

Assessment of antifungal activity of herbal and conventional toothpastes against clinical isolates of Candida albicans

PubMed Central

Adwan, Ghaleb; Salameh, Yousef; Adwan, Kamel; Barakat, Ali

2012-01-01

Objective To detect the anticandidal activity of nine toothpastes containing sodium fluoride, sodium monofluorophosphate and herbal extracts as an active ingredients against 45 oral and non oral Candida albicans (C. albicans) isolates. Methods The antifungal activity of these toothpaste formulations was determined using a standard agar well diffusion method. Statistical analysis was performed using a statistical package, SPSS windows version 15, by applying mean values using one-way ANOVA with post-hoc least square differences (LSD) method. A P value of less than 0.05 was considered significant. Results All toothpastes studied in our experiments were effective in inhibiting the growth of all C. albicans isolates. The highest anticandidal activity was obtained from toothpaste that containing both herbal extracts and sodium fluoride as active ingredients, while the lowest activity was obtained from toothpaste containing sodium monofluorophosphate as an active ingredient. Antifungal activity of Parodontax toothpaste showed a significant difference (P< 0.001) against C. albicans isolates compared to toothpastes containing sodium fluoride or herbal products. Conclusions In the present study, it has been demonstrated that toothpaste containing both herbal extracts and sodium fluoride as active ingredients are more effective in control of C. albicans, while toothpaste that containing monofluorophosphate as an active ingredient is less effective against C. albicans. Some herbal toothpaste formulations studied in our experiments, appear to be equally effective as the fluoride dental formulations and it can be used as an alternative to conventional formulations for individuals who have an interest in naturally-based products. Our results may provide invaluable information for dental professionals. PMID:23569933

CO{sub 2} Reuse in Petrochemical Facilities

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

Jason Trembly; Brian Turk; Maruthi Pavani

2010-12-31

To address public concerns regarding the consequences of climate change from anthropogenic carbon dioxide (CO{sub 2}) emissions, the U.S. Department of Energy's National Energy Technology Laboratory (DOE/NETL) is actively funding a CO{sub 2} management program to develop technologies capable of mitigating CO{sub 2} emissions from power plant and industrial facilities. Over the past decade, this program has focused on reducing the costs of carbon capture and storage technologies. Recently, DOE/NETL launched an alternative CO{sub 2} mitigation program focused on beneficial CO{sub 2} reuse to support the development of technologies that mitigate emissions by converting CO{sub 2} into valuable chemicals andmore » fuels. RTI, with DOE/NETL support, has been developing an innovative beneficial CO{sub 2} reuse process for converting CO{sub 2} into substitute natural gas (SNG) by using by-product hydrogen (H{sub 2)-containing fuel gas from petrochemical facilities. This process leveraged commercial reactor technology currently used in fluid catalytic crackers in petroleum refining and a novel nickel (Ni)-based catalyst developed by RTI. The goal was to generate an SNG product that meets the pipeline specifications for natural gas, making the SNG product completely compatible with the existing natural gas infrastructure. RTI's technology development efforts focused on demonstrating the technical feasibility of this novel CO{sub 2} reuse process and obtaining the necessary engineering information to design a pilot demonstration unit for converting about 4 tons per day (tons/day) of CO{sub 2} into SNG at a suitable host site. This final report describes the results of the Phase I catalyst and process development efforts. The methanation activity of several commercial fixed-bed catalysts was evaluated under fluidized-bed conditions in a bench-scale reactor to identify catalyst performance targets. RTI developed two fluidizable Ni-based catalyst formulations (Cat-1 and Cat-3) that demonstrated equal or better performance than that of commercial methanation catalysts. The Cat-1 and Cat-3 formulations were successfully scaled up using commercial manufacturing equipment at the Sud-Chemie Inc. pilot-plant facility in Louisville, KY. Pilot transport reactor testing with RTI's Cat-1 formulation at Kellog Brown & Root's Technology Center demonstrated the ability of the process to achieve high single-pass CO{sub 2} conversion. Using information acquired from bench- and pilot-scale testing, a basic engineering design package was prepared for a 4-ton/day CO{sub 2} pilot demonstration unit, including process and instrumentation diagrams, equipment list, control philosophy, and preliminary cost estimate.« less

Effects of formulation variables and post-compression curing on drug release from a new sustained-release matrix material: polyvinylacetate-povidone.

PubMed

Shao, Z J; Farooqi, M I; Diaz, S; Krishna, A K; Muhammad, N A

2001-01-01

A new commercially available sustained-release matrix material, Kollidon SR, composed of polyvinylacetate and povidone, was evaluated with respect to its ability to modulate the in vitro release of a highly water-soluble model compound, diphenhydramine HCl. Kollidon SR was found to provide a sustained-release effect for the model compound, with certain formulation and processing variables playing an important role in controlling its release kinetics. Formulation variables affecting the release include the level of the polymeric material in the matrix, excipient level, as well as the nature of the excipients (water soluble vs. water insoluble). Increasing the ratio of a water-insoluble excipient, Emcompress, to Kollidon SR enhanced drug release. The incorporation of a water-soluble excipient, lactose, accelerated its release rate in a more pronounced manner. Stability studies conducted at 40 degrees C/75% RH revealed a slow-down in dissolution rate for the drug-Kollidon SR formulation, as a result of polyvinylacetate relaxation. Further studies demonstrated that a post-compression curing step effectively stabilized the release pattern of formulations containing > or = 47% Kollidon SR. The release mechanism of Kollidon-drug and drug-Kollidon-Emcompress formulations appears to be diffusion controlled, while that of the drug-Kollidon-lactose formulation appears to be controlled predominantly by diffusion along with erosion.

Varying efficacy of superdisintegrants in orally disintegrating tablets among different manufacturers.

PubMed

Mittapalli, R K; Qhattal, H S Sha; Lockman, P R; Yamsani, M R

2010-11-01

The main objective of the present study was to develop an orally disintegrating tablet formulation of domperidone and to study the functionality differences of superdisintegrants each obtained from two different sources on the tablet properties. Domperidone tablets were formulated with different superdisintegrants by direct compression. The effect of the type of superdisintegrant, its concentration and source was studied by measuring the in-vitro disintegration time, wetting time, water absorption ratios, drug release by dissolution and in-vivo oral disintegration time. Tablets prepared with crospovidone had lower disintegration times than tablets prepared from sodium starchglycolate and croscarmellose sodium. Formulations prepared with Polyplasdone XL, Ac-Di-Sol, and Explotab (D series) were better than formulations prepared with superdisintegrants obtained from other sources (DL series) which had longer disintegration times and lower water uptake ratios. The in-vivo disintegration time of formulation D-106 containing polyplasdone XL was significantly lower than that of the marketed formulation Domel-MT. The results from this study suggest that disintegration of orally disintegrating tablets is dependent on the nature of superdisintegrant, concentration in the formulation and its source. Even though a superdisintegrant meets USP standards there can be a variance among manufacturers in terms of performance. This is not only limited to in-vitro studies but carries over to disintegration times in the human population.

Cognitive Hypnotherapy for Accessing and Healing Emotional Injuries for Anxiety Disorders.

PubMed

Alladin, Assen

2016-07-01

Although anxiety disorders on the surface may appear simple, they often represent complex problems that are compounded by underlying factors. For these reasons, treatment of anxiety disorders should be individualized. This article describes cognitive hypnotherapy, an individual comprehensive treatment protocol that integrates cognitive, behavioral, mindfulness, psychodynamic, and hypnotic strategies in the management of anxiety disorders. The treatment approach is based on the self-wounds model of anxiety disorders, which provides the rationale for integrating diverse strategies in the psychotherapy for anxiety disorders. Due to its evidence-based and integrated nature, the psychotherapy described here provides accuracy, efficacy, and sophistication in the formulation and treatment of anxiety disorders. This model can be easily adapted to the understanding and treatment of other emotional disorders.

Electromagnetic finite elements based on a four-potential variational principle

NASA Technical Reports Server (NTRS)

Schuler, James J.; Felippa, Carlos A.

1991-01-01

Electromagnetic finite elements based on a variational principle that uses the electromagnetic four-potential as a primary variable are derived. This choice is used to construct elements suitable for downstream coupling with mechanical and thermal finite elements for the analysis of electromagnetic/mechanical systems that involve superconductors. The main advantages of the four-potential as a basis for finite element formulation are that the number of degrees of freedom per node remains modest as the problem dimensionally increases, that jump discontinuities on interfaces are naturally accommodated, and that statics as well as dynamics may be treated without any a priori approximations. The new elements are tested on an axisymmetric problem under steady state forcing conditions. The results are in excellent agreement with analytical solutions.

An agent-based model for queue formation of powered two-wheelers in heterogeneous traffic

NASA Astrophysics Data System (ADS)

Lee, Tzu-Chang; Wong, K. I.

2016-11-01

This paper presents an agent-based model (ABM) for simulating the queue formation of powered two-wheelers (PTWs) in heterogeneous traffic at a signalized intersection. The main novelty is that the proposed interaction rule describing the position choice behavior of PTWs when queuing in heterogeneous traffic can capture the stochastic nature of the decision making process. The interaction rule is formulated as a multinomial logit model, which is calibrated by using a microscopic traffic trajectory dataset obtained from video footage. The ABM is validated against the survey data for the vehicular trajectory patterns, queuing patterns, queue lengths, and discharge rates. The results demonstrate that the proposed model is capable of replicating the observed queue formation process for heterogeneous traffic.

Herbal Remedies: A Boon for Diabetic Neuropathy.

PubMed

Tiwari, Reshu; Siddiqui, Mohd Haris; Mahmood, Tarique; Bagga, Paramdeep; Ahsan, Farogh; Shamim, Arshiya

2018-03-26

Diabetic neuropathy is a chronic complication of diabetes mellitus affecting about 50% of patients. Its symptoms include decreased motility and severe pain in peripheral parts. The pathogenesis involved is an abnormality in blood vessels that supply the peripheral nerves, metabolic disorders such as myo-inositol depletion, and increased nonenzymatic glycation. Moreover, oxidative stress in neurons results in activation of multiple biochemical pathways, which results in the generation of free radicals. Apart from available marketed formulations, extensive research is being carried out on herbal-based natural products to control hyperglycemia and its associated complications. This review is focused to provide a summary on diabetic neuropathy covering its etiology, types, and existing work on herbal-based therapies, which include pure compounds isolated from plant materials, plant extracts, and Ayurvedic preparations.

Lesson learned from nature for the development of novel anti-cancer agents: implication of isoflavone, curcumin, and their synthetic analogs.

PubMed

Sarkar, Fazlul H; Li, Yiwei; Wang, Zhiwei; Padhye, Subhash

2010-06-01

In recent years, naturally occurring dietary compounds have received greater attention in the field of cancer prevention and treatment research. Among them, isoflavone genistein and curcumin are very promising anti-cancer agents because of their non-toxic and potent anti-cancer properties. However, it is important to note that the low water solubility, poor in vivo bioavailability and unacceptable pharmacokinetic profile of these natural compounds limit their efficacy as anti-cancer agents for solid tumors. Therefore, the development of synthetic analogs of isoflavone and curcumin based on the structure-activity assay, and the encapsulation of isoflavone and curcumin with liposome or nanoparticle for enhancing the anti-tumor activity of these natural agents, is an exciting area of research. Emerging in vitro and in vivo studies clearly suggest that these analogs and formulations of natural compounds could be much more potent for the prevention and/or treatment of various cancers. In this review article, we will summarize the current knowledge regarding the anti-cancer effect of natural compounds and their analogs, the regulation of cell signaling by these agents, and the structure-activity relationship for better design of novel anti-cancer agents, which could open newer avenues for the prevention of tumor progression and/or treatment of human malignancies.

Lesson Learned from Nature for the Development of Novel Anti-Cancer Agents: Implication of Isoflavone, Curcumin, and their Synthetic Analogs

PubMed Central

Sarkar, Fazlul H.; Li, Yiwei; Wang, Zhiwei; Padhye, Subhash

2011-01-01

In recent years, naturally occurring dietary compounds have received greater attention in the field of cancer prevention and treatment research. Among them, isoflavone genistein and curcumin are very promising anti-cancer agents because of their non-toxic and potent anti-cancer properties. However, it is important to note that the low water solubility, poor in vivo bioavailability and unacceptable pharmacokinetic profile of these natural compounds limit their efficacy as anti-cancer agents for solid tumors. Therefore, the development of synthetic analogs of isoflavone and curcumin based on the structure-activity assay, and the encapsulation of isoflavone and curcumin with liposome or nanoparticle for enhancing the anti-tumor activity of these natural agents, is an exciting area of research. Emerging in vitro and in vivo studies clearly suggest that these analogs and formulations of natural compounds could be much more potent for the prevention and/or treatment of various cancers. In this review article, we will summarize the current knowledge regarding the anti-cancer effect of natural compounds and their analogs, the regulation of cell signaling by these agents, and the structure-activity relationship for better design of novel anti-cancer agents, which could open newer avenues for the prevention of tumor progression and/or treatment of human malignancies. PMID:20345353

From Romanticism to Deep Ecology: The Continuing Evolution in American Environmental Thought.

ERIC Educational Resources Information Center

Ackerson, David

2000-01-01

Describes the contributions to deep ecology of Henry Thoreau, who advocated acting upon strongly held convictions; John Muir, who adopted a biocentric view of nature; and Aldo Leopold, who formulated an egalitarian ecosystem ethic. While deep ecology is moving toward a new vision of humankind's relation to nature, it has yet to coalesce into a…

Teaching the Conceptual Scheme "The Particle Nature of Matter" in the Elementary School.

ERIC Educational Resources Information Center

Pella, Milton O.; And Others

Conclusions of an extensive project aimed to prepare lessons and associated materials related to teaching concepts included in the scheme "The Particle Nature of Matter" for grades two through six are presented. The hypothesis formulated for the project was that children in elementary schools can learn theoretical concepts related to the particle…

From landscapes to soundscapes: understanding and managing natural quiet in the national parks

Treesearch

Robert Manning; William Valliere; Jeffery Hallo; Peter Newman; Ericka Pilcher; Michael Savidge; Dan Dugan

2007-01-01

Research at Muir Woods Natural Monument suggests that soundscapes are an important component of parks and outdoor recreation, that human-caused noise is a potentially important indicator of quality for park soundscapes, and that visitors have normative standards for the maximum acceptable level of human-caused noise in parks. Formulating indicators and standards of...

In vitro permeation and disposition of niacinamide in silicone and porcine skin of skin barrier-mimetic formulations.

PubMed

Haque, Tasnuva; Lane, Majella E; Sil, Bruno C; Crowther, Jonathan M; Moore, David J

2017-03-30

Niacinamide (NIA) is an amide form of vitamin B3 which is used in cosmetic formulations to improve various skin conditions and it has also been shown to increase stratum corneum thickness following repeated application. In this study, three doses (5, 20 and 50μL per cm 2 ) of two NIA containing oil-in-water skin barrier-mimetic formulations were evaluated in silicone membrane and porcine ear skin and compared with a commercial control formulation. Permeation studies were conducted over 24h in Franz cells and at the end of the experiment membranes were washed and niacinamide was extracted. For the three doses, retention or deposition of NIA was generally higher in porcine skin compared with silicone membrane, consistent with the hydrophilic nature of the active. Despite the control containing a higher amount of active, comparable amounts of NIA were deposited in skin for all formulations for all doses; total skin absorption values (permeation and retention) of NIA were also comparable across all formulations. For infinite (50μL) and finite (5μL) doses the absolute permeation of NIA from the control formulation was significantly higher in porcine skin compared with both test formulations. This likely reflects differences in formulation components and/or presence of skin penetration enhancers in the formulations. Higher permeation for the 50 and 20μL dose was also evident in porcine skin compared with silicone membrane but the opposite is the case for the finite dose. The findings point to the critical importance of dose and occlusion when evaluating topical formulations in vitro and also the likelihood of exaggerated effects of excipients on permeation at infinite and pseudo-finite dose applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Pancreas cancer meets the thunder god.

PubMed

Hingorani, Sunil R; Potter, John D

2012-10-17

A new formulation of a natural product shows remarkable activity against pancreatic ductal adenocarcinoma across a number of preclinical model systems. These findings set the stage for a clinical trial.

Formulation, Preparation, and Characterization of Polyurethane Foams

ERIC Educational Resources Information Center

Pinto, Moises L.

2010-01-01

Preparation of laboratory-scale polyurethane foams is described with formulations that are easy to implement in experiments for undergraduate students. Particular attention is given to formulation aspects that are based on the main chemical reactions occurring in polyurethane production. This allows students to develop alternative formulations to…

Co-Formulants in Glyphosate-Based Herbicides Disrupt Aromatase Activity in Human Cells below Toxic Levels

PubMed Central

Defarge, Nicolas; Takács, Eszter; Lozano, Verónica Laura; Mesnage, Robin; Spiroux de Vendômois, Joël; Séralini, Gilles-Eric; Székács, András

2016-01-01

Pesticide formulations contain declared active ingredients and co-formulants presented as inert and confidential compounds. We tested the endocrine disruption of co-formulants in six glyphosate-based herbicides (GBH), the most used pesticides worldwide. All co-formulants and formulations were comparably cytotoxic well below the agricultural dilution of 1% (18–2000 times for co-formulants, 8–141 times for formulations), and not the declared active ingredient glyphosate (G) alone. The endocrine-disrupting effects of all these compounds were measured on aromatase activity, a key enzyme in the balance of sex hormones, below the toxicity threshold. Aromatase activity was decreased both by the co-formulants alone (polyethoxylated tallow amine—POEA and alkyl polyglucoside—APG) and by the formulations, from concentrations 800 times lower than the agricultural dilutions; while G exerted an effect only at 1/3 of the agricultural dilution. It was demonstrated for the first time that endocrine disruption by GBH could not only be due to the declared active ingredient but also to co-formulants. These results could explain numerous in vivo results with GBHs not seen with G alone; moreover, they challenge the relevance of the acceptable daily intake (ADI) value for GBHs exposures, currently calculated from toxicity tests of the declared active ingredient alone. PMID:26927151

Assessment of In vitro Sun Protection Factor of Calendula Officinalis L. (Asteraceae) Essential Oil Formulation.

PubMed

Mishra, Ak; Mishra, A; Chattopadhyay, P

2012-01-01

The present study was undertaken to study the sunscreen activity of herbal formulation. There is no evidence of the sun protection factor (SPF) studies on essential oil of Calendula flowers (Calendula officinalis L., Asteraceae). The study investigates the in vitro SPF by ultraviolet specrtophotometry method of Calendula flower oil in a cream formulation. Calendula oil was isolated by Clavenger's apparatus, compositions were identified by GC-MS and the cream of calendula flower oil was prepared by homogenization method followed by evaluation for physical parameters. The sun protection factor of cream was evaluated by in vitro method employing UV-visible spectrophotometer (Shimazdu-1600). The SPF of Calendula oil in cream formulation exhibited good activity (SPF = 14.84 ± 0.16). Finding of this study suggested that calendula oil cream can be used to protect the skin from UV radiations in form of sunscreen cream and to maintain the natural pigmentation of the skin.

Development of poloxamer gel formulations via hot-melt extrusion technology.

PubMed

Mendonsa, Nicole S; Murthy, S Narasimha; Hashemnejad, Seyed Meysam; Kundu, Santanu; Zhang, Feng; Repka, Michael A

2018-02-15

Poloxamer gels are conventionally prepared by the "hot" or the "cold" process. But these techniques have some disadvantages such as high energy consumption, requires expensive equipment and often have scale up issues. Therefore, the objective of this work was to develop poloxamer gels by hot-melt extrusion technology. The model drug selected was ketoprofen. The formulations developed were 30% and 40% poloxamer gels. Of these formulations, the 30% poloxamer gels were selected as ideal gels. DSC and XRD studies showed an amorphous nature of the drug after extrusion. It was observed from the permeation studies that with increasing poloxamer concentration, a decrease in drug permeation was obtained. Other studies conducted for the formulations included in-vitro release studies, texture analysis, rheological studies and pH measurements. In conclusion, the hot-melt extrusion technology could be successfully employed to develop poloxamer gels by overcoming the drawbacks associated with the conventional techniques. Published by Elsevier B.V.

Colloidal Aggregate Structure under Shear by USANS

NASA Astrophysics Data System (ADS)

Chatterjee, Tirtha; van Dyk, Antony K.; Ginzburg, Valeriy V.; Nakatani, Alan I.

2015-03-01

Paints are complex formulations of polymeric binders, inorganic pigments, dispersants, surfactants, colorants, rheology modifiers, and other additives. A commercially successful paint exhibits a desired viscosity profile over a wide shear rate range from 10-5 s-1 for settling to >104 s-1 for rolling, and spray applications. Understanding paint formulation structure is critical as it governs the paint viscosity profile. However, probing paint formulation structure under shear is a challenging task due to the formulation complexity containing structures with different hierarchical length scales and their alterations under the influence of an external flow field. In this work mesoscale structures of paint formulations under shear are investigated using Ultra Small-Angle Neutron Scattering (rheo-USANS). Contrast match conditions were utilized to independently probe the structure of latex binder particle aggregates and the TiO2 pigment particle aggregates. Rheo-USANS data revealed that the aggregates are fractal in nature and their self-similarity dimensions and correlations lengths depend on the chemistry of the binder particles, the type of rheology modifier present and the shear stress imposed upon the formulation. These results can be explained in the framework of diffusion and reaction limited transient aggregates structure evolution under simple shear.

Black Ink of Activated Carbon Derived From Palm Kernel Cake (PKC)

NASA Astrophysics Data System (ADS)

Selamat, M. H.; Ahmad, A. H.

2009-06-01

Recycling the waste from natural plant to produce useful end products will benefit many industries and help preserve the environment. The research reported in this paper is an investigation on the use of the natural waste of palm kernel cake (PKC) to produce carbon residue as a black carbon for pigment source by using pyrolysis process. The activated carbons (AC) is produced in powder form using ball milling process. Rheological spectra in ink is one of quality control process in determining its performance properties. Findings from this study will help expand the scientific knowledge-base for black ink production and formulation base on PKC. Various inks with different weight percentage compositions of AC will be made and tested against its respective rheological properties in order to determine ideal ink printing system. The items in the formulation used comprised of organic and bio-waste materials with added additive to improve the quality of the black ink. Modified Polyurethane was used as binder. The binder's properties highlighted an ideal vehicle to be applied for good black ink opacity performance. The rheological behaviour is a general foundation for ink characterization where the wt% of AC-PKC resulted in different pseudoplastic behaviors, including the Newtonian behavior. The result found that Newtonian field was located in between 2 wt% and 10 wt% of AC-PKC composition with binder. Mass spectroscopy results shown that the carbon content in PKC is high and very suitable for black performance. In the ageing test, the pigment of PKC perform fairly according to the standard pigment of Black carbon (CB) of ferum oxide pigment. The contact angle for substrate's wettability of the ink system shown a good angle proven to be a water resistive coating on paper subtrates; an advantage of the PKC ink pigment performance.

Effects of organic amendments on the toxicity and bioavailability of cadmium and copper in spiked formulated sediments

USGS Publications Warehouse

Besser, J.M.; Brumbaugh, W.G.; May, T.W.; Ingersoll, C.G.

2003-01-01

We evaluated the partitioning and toxicity of cadmium (Cd) and copper (Cu) spiked into formulated sediments containing two types of organic matter (OM), i.e., cellulose and humus. Amendments of cellulose up to 12.5% total organic carbon (TOC) did not affect partitioning of Cd or Cu between sediment and pore water and did not significantly affect the toxicity of spiked sediments in acute toxicity tests with the amphipod Hyalella azteca. In contrast, amendments of natural humus shifted the partitioning of both Cd and Cu toward greater concentrations in sediment and lesser concentrations in pore water and significantly reduced toxic effects of both metals. Thresholds for toxicity, based on measured metal concentrations in whole sediment, were greater for both Cd and Cu in sediments amended with a low level of humus (2.9% TOC) than in sediments without added OM. Amendments with a high level of humus (8.9% TOC) eliminated toxicity at the highest spike concentrations of both metals (sediment concentrations of 12.4 ??g Cd/g and 493 ??g Cu/g). Concentrations of Cd in pore water associated with acute toxicity were similar between sediments with and without humus amendments, suggesting that toxicity of Cd was reduced primarily by sorption to sediment OM. However, toxic effects of Cu in humus treatments were associated with greater pore-water concentrations than in controls, suggesting that toxicity of Cu was reduced both by sorption and by complexation with soluble ligands. Both sorption and complexation by OM tend to make proposed sediment quality guidelines (SQGs) based on total metal concentrations more protective for high-OM sediments. Our results suggest that the predictive ability of SQGs could be improved by models of metal interactions with natural OM in sediment and pore water.

Effects of organic amendments on the toxicity and bioavailability of cadmium and copper in spiked formulated sediments.

PubMed

Besser, John M; Brumbaugh, William G; May, Thomas W; Ingersoll, Christopher G

2003-04-01

We evaluated the partitioning and toxicity of cadmium (Cd) and copper (Cu) spiked into formulated sediments containing two types of organic matter (OM), i.e., cellulose and humus. Amendments of cellulose up to 12.5% total organic carbon (TOC) did not affect partitioning of Cd or Cu between sediment and pore water and did not significantly affect the toxicity of spiked sediments in acute toxicity tests with the amphipod Hyalella azteca. In contrast, amendments of natural humus shifted the partitioning of hoth Cd and Cu toward greater concentrations in sediment and lesser concentrations in pore water and significantly reduced toxic effects of both metals. Thresholds for toxicity, based on measured metal concentrations in whole sediment, were greater for both Cd and Cu in sediments amended with a low level of humus (2.9% TOC) than in sediments without added OM. Amendments with a high level of humus (8.9% TOC) eliminated toxicity at the highest spike concentrations of both metals (sediment concentrations of 12.4 microg Cd/g and 493 microg Cu/g). Concentrations of Cd in pore water associated with acute toxicity were similar between sediments with and without humus amendments, suggesting that toxicity of Cd was reduced primarily by sorption to sediment OM. However, toxic effects of Cu in humus treatments were associated with greater pore-water concentrations than in controls, suggesting that toxicity of Cu was reduced both by sorption and by complexation with soluble ligands. Both sorption and complexation by OM tend to make proposed sediment quality guidelines (SQGs) based on total metal concentrations more protective for high-OM sediments. Our results suggest that the predictive ability of SQGs could be improved by models of metal interactions with natural OM in sediment and pore water.

Generalizable open source urban water portfolio simulation framework demonstrated using a multi-objective risk-based planning benchmark problem.

NASA Astrophysics Data System (ADS)

Trindade, B. C.; Reed, P. M.

2017-12-01

The growing access and reduced cost for computing power in recent years has promoted rapid development and application of multi-objective water supply portfolio planning. As this trend continues there is a pressing need for flexible risk-based simulation frameworks and improved algorithm benchmarking for emerging classes of water supply planning and management problems. This work contributes the Water Utilities Management and Planning (WUMP) model: a generalizable and open source simulation framework designed to capture how water utilities can minimize operational and financial risks by regionally coordinating planning and management choices, i.e. making more efficient and coordinated use of restrictions, water transfers and financial hedging combined with possible construction of new infrastructure. We introduce the WUMP simulation framework as part of a new multi-objective benchmark problem for planning and management of regionally integrated water utility companies. In this problem, a group of fictitious water utilities seek to balance the use of the mentioned reliability driven actions (e.g., restrictions, water transfers and infrastructure pathways) and their inherent financial risks. Several traits of this problem make it ideal for a benchmark problem, namely the presence of (1) strong non-linearities and discontinuities in the Pareto front caused by the step-wise nature of the decision making formulation and by the abrupt addition of storage through infrastructure construction, (2) noise due to the stochastic nature of the streamflows and water demands, and (3) non-separability resulting from the cooperative formulation of the problem, in which decisions made by stakeholder may substantially impact others. Both the open source WUMP simulation framework and its demonstration in a challenging benchmarking example hold value for promoting broader advances in urban water supply portfolio planning for regions confronting change.

[Climate change risk of nature reserve and its assessment: A case study of Dalinuoer National Nature Reserve in Inner Mongolia Autonomous Region].

PubMed

Zhao, Wei; Shen, Wei Shou; Liu, Hai Yue

2016-12-01

According to the theoretical framework of addressing climate change based on risk mana-gement and the challenge to nature reserve management under climate change, climate change risk of nature reserve was analyzed and defined. Focus on birds and water habitat, grassland habitat, forest habitat, wetland habitat in Dalinuoer Nature Reserve, risk assessment method of nature reserve under climate change was formulated, climate change risks to Dalinuoer Nature Reserve and its habitats were assessed and predicted. The results showed that, during the period from 1997 to 2010, there was significant volatility in dynamic changes of climate change risks to Dalinuoer Nature Reserve and waterbody, grassland, forest, wetland in the region, Dalinuoer Nature Reserve and its habitats were in status of risk in 1999, 2001, 2005 and 2008, wetland habitat was also in status of risk in 2002 and 2004. Under scenario A, B and C, climate change risks to Dalinuoer Nature Reserve and waterbody, grassland, forest, wetland in the region would be more serious in 2020 and 2030, compared with the 2010 level. Climate change risks to different habitats were different significantly, with most serious climate change risk to wetland habitat due to its sensitivity to climate change and rich bird resources. The effect of climate change on nature reserve and related risk would be aggravated by excess utilization of water resource and grassland resource. As climate change risks had appeared in Dalinuoer Nature Reserve, risk management associated with climate change could greatly help to maintain and enhance biodiversity protection function of nature reserves.

Ivermectin disposition kinetics after subcutaneous and intramuscular administration of an oil-based formulation to cattle.

PubMed

Lifschitz, A; Virkel, G; Pis, A; Imperiale, F; Sanchez, S; Alvarez, L; Kujanek, R; Lanusse, C

1999-10-01

Slight differences in formulation may change the plasma kinetics and ecto-endoparasiticide activity of endectocide compounds. This work reports on the disposition kinetics and plasma availability of ivermectin (IVM) after subcutaneous (SC) and intramuscular (IM) administration as an oil-based formulation to cattle. Parasite-free Aberdeen Angus calves (n = 24; 240-280 kg) were divided into three groups (n = 8) and treated (200 microg/kg) with either an IVM oil-based pharmaceutical preparation (IVM-TEST formulation) (Bayer Argentina S.A.) given by subcutaneous (Group A) and intramuscular (Group B) injections or the IVM-CONTROL (non-aqueous formulation) (Ivomec, MSD Agvet) subcutaneously administered (Group C). Blood samples were taken over 35 days post-treatment and the recovered plasma was extracted and analyzed by HPLC using fluorescence detection. IVM was detected in plasma between 12 h and 35 days post-administration of IVM-TEST (SC and IM injections) and IVM-CONTROL formulations. Prolonged IVM absorption half-life (p < 0.05) and delayed peak plasma concentration (p < 0.001) were obtained following the SC administration of the IVM-TEST compared to the IVM-CONTROL formulation. No differences in total plasma availability were observed among treatments. However, the plasma residence time and elimination half-life of IVM were significantly longer after injection of the IVM-TEST formulation. IVM plasma concentrations were above 0.5 ng/ml for 20.6 (CONTROL) and 27.5 days (IVM-TEST SC), respectively (p < 0.05). The modified kinetic behaviour of IVM obtained after the administration of the novel oil-based formulation examined in this trial, compared to the standard preparation, may positively impact on its strategic use in cattle.

Essential oil based polymeric patch development and evaluating its repellent activity against mosquitoes.

PubMed

Chattopadhyay, Pronobesh; Dhiman, Sunil; Borah, Somi; Rabha, Bipul; Chaurasia, Aashwin Kumar; Veer, Vijay

2015-07-01

Essential oil based insect repellents are environment friendly and provide dependable personal protection against the bites of mosquitoes and other blood-sucking insects. In the present study, optimized mixture of three essential oils was embedded into the ethylcellulose (EC) and polyvinylpyrrolidone (PVP K-30) polymers to develop essential oils based patch type mosquito repellent formulation. The developed formulation was characterized for various physico-chemical properties, oil release efficiency and essential oil-polymer interaction. Repellent activity of the formulation was evaluated against Ae. (S) albopictus mosquitoes and compared with commercially available synthetic insecticide based mosquito repellent cream Odomos(®) in the laboratory. The developed patches were 100% flat and there was no interaction between oil components and the excipients. Patches were smooth, homogenous and provided excellent mosquito repellent activity comparable to Odomos(®) under laboratory condition. Morphological and physico-chemical characterization indicated that the formulation was stable and suitable with the polymeric combination. The patch formulation did not show any inhalation toxicity in experimental Wistar rat. The repellent patches developed and evaluated currently, may provide a suitable, eco-friendly, acceptable and safe alternative to the existing synthetic repellent formulations for achieving protection against mosquitoes. Copyright © 2015 Elsevier B.V. All rights reserved.

Hydrophobic polymers for orodispersible films: a quality by design approach.

PubMed

Borges, Ana Filipa; Silva, Branca M A; Silva, Cláudia; Coelho, Jorge F J; Simões, Sérgio

2016-10-01

To develop orodispersible films (ODF) based on hydrophobic polymers with higher stability to ordinary environmental humidity conditions without compromising their fast disintegration time. A quality by design approach was applied to screen three different formulations each one based on a different hydrophobic polymer: polyvinyl acetate, methacrylate-based copolymer and shellac. The screening formulations were characterized regarding their mechanical properties, residual water content, disintegration time and appearance, in order to find a suitable ODF formulation according to established critical quality attributes. The selected critical process parameters for the selection of appropriate ODF formulations were the percentage of the different excipients and the plasticizer type. Three hydrophobic-based matrices with fast disintegration were developed. These were generically composed by a hydrophobic polymer, a stabilizer, a disintegrant and a plasticizer. It verified that the common components within the three different formulations behave differently depending on the system/chemical environment that they were included. It was shown that it is possible to develop oral films based on hydrophobic polymers with fast disintegration time, good texture and appearance, breaking a paradigm of the ODF research field.

Chitosan encapsulation of essential oil "cocktails" with well-defined binary Zn(II)-Schiff base species targeting antibacterial medicinal nanotechnology.

PubMed

Halevas, Eleftherios; Nday, Christiane M; Chatzigeorgiou, Evanthia; Varsamis, Vasileios; Eleftheriadou, Despoina; Jackson, Graham E; Litsardakis, Georgios; Lazari, Diamanto; Ypsilantis, Konstantinos; Salifoglou, Athanasios

2017-11-01

The advent of biodegradable nanomaterials with enhanced antibacterial activity stands as a challenge to the global research community. In an attempt to pursue the development of novel antibacterial medicinal nanotechnology, we herein a) synthesized ionic-gelated chitosan nanoparticles, b) compared and evaluated the antibacterial activity of essential oils extracted from nine different herbs (Greek origin) and their combinations with a well-defined antibacterial Zn(II)-Schiff base compound, and c) encapsulated the most effective hybrid combination of Zn(II)-essential oils inside the chitosan matrix, thereby targeting well-formulated nanoparticles of distinct biological impact. The empty and loaded chitosan nanoparticles were physicochemically characterized by FT-IR, Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), with the entrapment and drug release studies being conducted through UV-Visible and atomic absorption techniques. The antimicrobial properties of the novel hybrid materials were demonstrated against Gram positive (S. aureus, B. subtilis, and B. cereus) and Gram negative (E. coli and X. campestris) bacteria using modified agar diffusion methods. The collective physicochemical profile of the hybrid Zn(II)-essential oil cocktails, formulated so as to achieve optimal activity when loaded to chitosan nanoparticles, signifies the importance of design in the development of efficient nanomedicinal pharmaceuticals a) based on both natural products and biogenic metal ionic cofactors, and b) targeting bacterial infections and drug resistance. Copyright © 2017 Elsevier Inc. All rights reserved.

A universal constraint-based formulation for freely moving immersed bodies in fluids

NASA Astrophysics Data System (ADS)

Patankar, Neelesh A.

2012-11-01

Numerical simulation of moving immersed bodies in fluids is now practiced routinely. A variety of variants of these approaches have been published, most of which rely on using a background mesh for the fluid equations and tracking the body using Lagrangian points. In this talk, generalized constraint-based governing equations will be presented that provide a unified framework for various immersed body techniques. The key idea that is common to these methods is to assume that the entire fluid-body domain is a ``fluid'' and then to constrain the body domain to move in accordance with its governing equations. The immersed body can be rigid or deforming. The governing equations are developed so that they are independent of the nature of temporal or spatial discretization schemes. Specific choices of time stepping and spatial discretization then lead to techniques developed in prior literature ranging from freely moving rigid to elastic self-propelling bodies. To simulate Brownian systems, thermal fluctuations can be included in the fluid equations via additional random stress terms. Solving the fluctuating hydrodynamic equations coupled with the immersed body results in the Brownian motion of that body. The constraint-based formulation leads to fractional time stepping algorithms a la Chorin-type schemes that are suitable for fast computations of rigid or self-propelling bodies whose deformation kinematics are known. Support from NSF is gratefully acknowledged.

Hydroalcoholic extract based-ointment from Punica granatum L. peels with enhanced in vivo healing potential on dermal wounds.

PubMed

Hayouni, E A; Miled, K; Boubaker, S; Bellasfar, Z; Abedrabba, M; Iwaski, H; Oku, H; Matsui, T; Limam, F; Hamdi, M

2011-08-15

The present study reports for the first time, the in vivo wound healing potential of Punica granatum L. peels. A 5% (w/w) methanolic extract based-ointment was formulated and evaluated for its wound healing in guinea pigs. The ointment was applied in vivo on the paravertebral area of twelve excised wounded models once a day for 10 consecutive days. The ointment significantly enhanced the wound contraction and the period of epithelialization as assessed by the mechanical (contraction rate, tensile strength), the biochemical (increasing of collagen, DNA and proteins synthesis) and the histopathological characteristics. Such investigation was encouraged by the efficiency of the methanolic extract as antimicrobial and antioxidant. Indeed, the extract showed antioxidant activity as strong as natural and synthetic compounds (Trolox, BHA, Quercetin). Furthermore, the extract exhibited significant antibacterial and antifungal activity against almost all tested bacteria: Pseudomonas aeruginosa ATCC 9027, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Klebsiella pneumoniae, Salmonella anatum, Salmonella typhimurium, Streptococcus pneumoniae, and fungi Candida albicans, Candida glabrata, Trichopyton rubrum and Aspergillus niger. The formulated ointment might well find use as skin repair agent without hazard to human health based on these results and on the fact that it has been well established that the extracts of pomegranate used in conditions similar to those applied by traditional medicine, showed no toxic effects. Copyright © 2011 Elsevier GmbH. All rights reserved.

Composite films based on biorelated agro-industrial waste and poly(vinyl alcohol). Preparation and mechanical properties characterization.

PubMed

Chiellini, E; Cinelli, P; Imam, S H; Mao, L

2001-01-01

As a part of an ongoing project on the production of composite materials based on poly(vinyl alcohol) (PVA) and polymeric materials from renewable resources, the present paper reports on the incorporation of agricultural waste materials as organic fillers in a film matrix based on PVA as continuous phase. In this study lignocellulosic fibers byproducts, derived from sugar cane (SC) and apple (AP) and orange (OR) fruit juice extraction, were cast from PVA aqueous solutions. The effect of fiber type and composition on the relative properties of cast films was evaluated and compared. OR resulted to be suitable for blending in higher amounts by weight than SC and AP. Glycerol and urea were added as plasticizing agents and were observed to be effective in giving flexible films. Additionally, cornstarch was added to further increase the composition of polymers from renewable resources in cost-effective and ecoefficient composite film formulations. The prepared films resulted sensitive to moisture and water. To reduce water sensitivity, hexamethoxymethylmelamine (HMMM) was tested as a cross-linking agent for the present composite formulations. Cross-linked films exhibited significant improvement in water-resistance that can be taken as a tuneable structural feature for customized applications. The mechanical properties of the prepared composite films (elongation at break, tensile strength, Young modulus) were found to be dependent upon the nature and content of the filler and on environmental conditions.

A unifying Bayesian account of contextual effects in value-based choice

PubMed Central

Friston, Karl J.; Dolan, Raymond J.

2017-01-01

Empirical evidence suggests the incentive value of an option is affected by other options available during choice and by options presented in the past. These contextual effects are hard to reconcile with classical theories and have inspired accounts where contextual influences play a crucial role. However, each account only addresses one or the other of the empirical findings and a unifying perspective has been elusive. Here, we offer a unifying theory of context effects on incentive value attribution and choice based on normative Bayesian principles. This formulation assumes that incentive value corresponds to a precision-weighted prediction error, where predictions are based upon expectations about reward. We show that this scheme explains a wide range of contextual effects, such as those elicited by other options available during choice (or within-choice context effects). These include both conditions in which choice requires an integration of multiple attributes and conditions where a multi-attribute integration is not necessary. Moreover, the same scheme explains context effects elicited by options presented in the past or between-choice context effects. Our formulation encompasses a wide range of contextual influences (comprising both within- and between-choice effects) by calling on Bayesian principles, without invoking ad-hoc assumptions. This helps clarify the contextual nature of incentive value and choice behaviour and may offer insights into psychopathologies characterized by dysfunctional decision-making, such as addiction and pathological gambling. PMID:28981514

Field Demonstration of Biobased Fluids in Military Construction Equipment

DTIC Science & Technology

2007-07-01

155C 35.85 @155C 38.0 @180C Swelling of Synthetic Rubber , NBR , L, % FTM 3603 30.5 20.63 11.17 12.76 20.05 Evaporation Loss, %, 100 deg C, 1...basically divided into two groups. One is natural rubber and the other one is a synthetic elastomer. Their formulations and physical properties are not...reference elastomer was specially formulated with Nitrile or Buna N ( NBR -L) material and is widely used in the many hydraulic specifications including

Spray-on tanning.

PubMed

Rogers, Cindy J

2005-01-01

The modern formulation of dihydroxyacetone (DHA), the only sunless tanning solution approved by the Food and Drug Administration (FDA), is combined with bronzers and moisturizers to deliver a cosmetically acceptable skin color and a natural-looking tan without ultraviolet (UV) exposure. Spray-on tanning products, which deliver this formulation evenly to achieve a full body tan, may be applied in a tanning booth, airbrushed on by a technician, or sprayed on at home, and they appear to offer a generally safe alternative for patients who seek a suntanned appearance.

The intelligent user interface for NASA's advanced information management systems

NASA Technical Reports Server (NTRS)

Campbell, William J.; Short, Nicholas, Jr.; Rolofs, Larry H.; Wattawa, Scott L.

1987-01-01

NASA has initiated the Intelligent Data Management Project to design and develop advanced information management systems. The project's primary goal is to formulate, design and develop advanced information systems that are capable of supporting the agency's future space research and operational information management needs. The first effort of the project was the development of a prototype Intelligent User Interface to an operational scientific database, using expert systems and natural language processing technologies. An overview of Intelligent User Interface formulation and development is given.

BRST formulation of 4-monopoles

NASA Astrophysics Data System (ADS)

Gianvittorio, R.; Martin, I.; Restuccia, A.

1996-11-01

A supersymmetric gauge-invariant action is constructed over any four-dimensional Riemannian manifold describing Witten's theory of 4-monopoles. The topological supersymmetric algebra closes off-shell. The multiplets include the auxiliary fields and the Wess - Zumino fields in an unusual way, arising naturally from BRST gauge fixing. A new canonical approach over Riemann manifolds is followed, using a Morse function as a Euclidean time and taking into account the BRST boundary conditions that come from the BFV formulation. This allows a construction of the effective action starting from gauge principles.

The physicochemical characterization and in vitro/in vivo evaluation of natural surfactants-based emulsions as vehicles for diclofenac diethylamine.

PubMed

Vucinić-Milanković, Nada; Savić, Snezana; Vuleta, Gordana; Vucinić, Slavica

2007-03-01

Two sugar-based emulsifiers, cetearyl alcohol & cetearyl glycoside and sorbitan stearate & sucrose cocoate, known as potential promoters of lamellar liquid crystals/gel phases, were investigated in order to formulate an optimal vehicle for amphiphilic drug - diclofenac diethylamine (DDA). Physico-chemical characterization and study of vehicle's physical stability were performed. Then, the in vitro DDA liberation profile, dependent on the mode of drug incorporation to the system, and the in vivo, short-term effects of chosen samples on skin parameters were examined. Droplets size distribution and rheological behavior indicated satisfying physical stability of both types of vehicles. Unexpectedly, the manner of DDA incorporation to the system had no significant influence on DDA release. In vivo study pointed to emulsion's favorable potential for skin hydration and barrier improvement, particularly in cetearyl glycoside-based vehicle.

A search for optimal parameters of resonance circuits ensuring damping of electroelastic structure vibrations based on the solution of natural vibration problem

NASA Astrophysics Data System (ADS)

Oshmarin, D.; Sevodina, N.; Iurlov, M.; Iurlova, N.

2017-06-01

In this paper, with the aim of providing passive control of structure vibrations a new approach has been proposed for selecting optimal parameters of external electric shunt circuits connected to piezoelectric elements located on the surface of the structure. The approach is based on the mathematical formulation of the natural vibration problem. The results of solution of this problem are the complex eigenfrequencies, the real part of which represents the vibration frequency and the imaginary part corresponds to the damping ratio, characterizing the rate of damping. A criterion of search for optimal parameters of the external passive shunt circuits, which can provide the system with desired dissipative properties, has been derived based on the analysis of responses of the real and imaginary parts of different complex eigenfrequencies to changes in the values of the parameters of the electric circuit. The efficiency of this approach has been verified in the context of natural vibration problem of rigidly clamped plate and semi-cylindrical shell, which is solved for series-connected and parallel -connected external resonance (consisting of resistive and inductive elements) R-L circuits. It has been shown that at lower (more energy-intensive) frequencies, a series-connected external circuit has the advantage of providing lower values of the circuit parameters, which renders it more attractive in terms of practical applications.

Evaluation of the resistance of a geopolymer-based drug delivery system to tampering.

PubMed

Cai, Bing; Engqvist, Håkan; Bredenberg, Susanne

2014-04-25

Tamper-resistance is an important property of controlled-release formulations of opioid drugs. Tamper-resistant formulations aim to increase the degree of effort required to override the controlled release of the drug molecules from extended-release formulations for the purpose of non-medical use. In this study, the resistance of a geopolymer-based formulation to tampering was evaluated by comparing it with a commercial controlled-release tablet using several methods commonly used by drug abusers. Because of its high compressive strength and resistance to heat, much more effort and time was required to extract the drug from the geopolymer-based formulation. Moreover, in the drug-release test, the geopolymer-based formulation maintained its controlled-release characteristics after milling, while the drug was released immediately from the milled commercial tablets, potentially resulting in dose dumping. Although the tampering methods used in this study does not cover all methods that abuser could access, the results obtained by the described methods showed that the geopolymer matrix increased the degree of effort required to override the controlled release of the drug, suggesting that the formulation has improved resistance to some common drug-abuse tampering methods. The geopolymer matrix has the potential to make the opioid product less accessible and attractive to non-medical users. Copyright © 2014 Elsevier B.V. All rights reserved.

Valorization of Tunisian alfa fibres and sumac tannins for the elaboration of biodegradable insulating panels

NASA Astrophysics Data System (ADS)

Saad, Houda; Charrier, Bertrand; Ayed, Naceur; Charrier-El-Bouhtoury, Fatima

2017-10-01

Alfa leaves are important renewable raw materials in Tunisia where they are used basically in handcrafts and paper industry. Sumac is also an abundant species in Tunisia known for its high tannin content and is basically used in traditional medicine. To valorize these natural resources, we studied, for the first time, the possibility of making insulating panels based on alfa fibres and sumac tannins based adhesive. Firstly, alfa leaves were treated with an alkali solution as it is one of the standard procedures commonly used in the paper industry to extract cellulosic fibres. Mercerization effects were studied by characterizing fibres thermal properties and fibres surface morphology. Secondly, the sumac tannin based resin was formulated and characterized. Finally, the insulating panel was elaborated and characterized by determining its thermal conductivity. The thermal gravimetric analysis results show improvement in the thermal stability of fibres after alkali treatment. Environmental Scanning Electron Microscopy showed changes on treated alfa surface which could promote the fibre-matrix adhesion. The reactivity of sumac tannins to formaldehyde test (Stiasny number) showed the possible use of sumac tannins in wood adhesive formulation. Thermomechanical analysis and strength analysis of sumac tannin/hexamin based resin highlighted acceptable bonding properties. The thermal conductivity measurement showed an average value equal to 0.110 W/m K. Contribution to the topical issue "Materials for Energy harvesting, conversion and storage II (ICOME 2016)", edited by Jean-Michel Nunzi, Rachid Bennacer and Mohammed El Ganaoui

Example-Based Image Colorization Using Locality Consistent Sparse Representation.

PubMed

Bo Li; Fuchen Zhao; Zhuo Su; Xiangguo Liang; Yu-Kun Lai; Rosin, Paul L

2017-11-01

Image colorization aims to produce a natural looking color image from a given gray-scale image, which remains a challenging problem. In this paper, we propose a novel example-based image colorization method exploiting a new locality consistent sparse representation. Given a single reference color image, our method automatically colorizes the target gray-scale image by sparse pursuit. For efficiency and robustness, our method operates at the superpixel level. We extract low-level intensity features, mid-level texture features, and high-level semantic features for each superpixel, which are then concatenated to form its descriptor. The collection of feature vectors for all the superpixels from the reference image composes the dictionary. We formulate colorization of target superpixels as a dictionary-based sparse reconstruction problem. Inspired by the observation that superpixels with similar spatial location and/or feature representation are likely to match spatially close regions from the reference image, we further introduce a locality promoting regularization term into the energy formulation, which substantially improves the matching consistency and subsequent colorization results. Target superpixels are colorized based on the chrominance information from the dominant reference superpixels. Finally, to further improve coherence while preserving sharpness, we develop a new edge-preserving filter for chrominance channels with the guidance from the target gray-scale image. To the best of our knowledge, this is the first work on sparse pursuit image colorization from single reference images. Experimental results demonstrate that our colorization method outperforms the state-of-the-art methods, both visually and quantitatively using a user study.

A stochastic HMM-based forecasting model for fuzzy time series.

PubMed

Li, Sheng-Tun; Cheng, Yi-Chung

2010-10-01

Recently, fuzzy time series have attracted more academic attention than traditional time series due to their capability of dealing with the uncertainty and vagueness inherent in the data collected. The formulation of fuzzy relations is one of the key issues affecting forecasting results. Most of the present works adopt IF-THEN rules for relationship representation, which leads to higher computational overhead and rule redundancy. Sullivan and Woodall proposed a Markov-based formulation and a forecasting model to reduce computational overhead; however, its applicability is limited to handling one-factor problems. In this paper, we propose a novel forecasting model based on the hidden Markov model by enhancing Sullivan and Woodall's work to allow handling of two-factor forecasting problems. Moreover, in order to make the nature of conjecture and randomness of forecasting more realistic, the Monte Carlo method is adopted to estimate the outcome. To test the effectiveness of the resulting stochastic model, we conduct two experiments and compare the results with those from other models. The first experiment consists of forecasting the daily average temperature and cloud density in Taipei, Taiwan, and the second experiment is based on the Taiwan Weighted Stock Index by forecasting the exchange rate of the New Taiwan dollar against the U.S. dollar. In addition to improving forecasting accuracy, the proposed model adheres to the central limit theorem, and thus, the result statistically approximates to the real mean of the target value being forecast.

Nanodesign of olein vesicles for the topical delivery of the antioxidant resveratrol.

PubMed

Pando, Daniel; Caddeo, Carla; Manconi, Maria; Fadda, Anna Maria; Pazos, Carmen

2013-08-01

The ex-vivo percutaneous absorption of the natural antioxidant resveratrol in liposomes and niosomes was investigated. The influence of vesicle composition on their physicochemical properties and stability was evaluated. Liposomes containing resveratrol were formulated using soy phosphatidylcholine (Phospholipon90G). Innovative niosomes were formulated using mono- or diglycerides: glycerol monooleate (Peceol) and polyglyceryl-3 dioleate (Plurol OleiqueCC), respectively, two suitable skin-compatible oleins used in pharmaceutical formulations as penetration enhancers. Small, negatively charged vesicles with a mean size of approximately 200 nm were prepared. The accelerated stability of vesicles was evaluated using Turbiscan Lab Expert, and the bilayer deformability was also assessed. Ex-vivo transdermal experiments were carried out in Franz diffusion cells, on newborn pig skin, to study the influence of the different vesicle formulations on resveratrol skin delivery. Results indicated a high cutaneous accumulation and a low transdermal delivery of resveratrol, especially when Peceol niosomes were used. Overall, niosomes formulated with Plurol oleique or Peceol showed a better behaviour than liposomes in the cutaneous delivery of resveratrol. © 2013 Royal Pharmaceutical Society.

Parallel Finite Element Domain Decomposition for Structural/Acoustic Analysis

NASA Technical Reports Server (NTRS)

Nguyen, Duc T.; Tungkahotara, Siroj; Watson, Willie R.; Rajan, Subramaniam D.

2005-01-01

A domain decomposition (DD) formulation for solving sparse linear systems of equations resulting from finite element analysis is presented. The formulation incorporates mixed direct and iterative equation solving strategics and other novel algorithmic ideas that are optimized to take advantage of sparsity and exploit modern computer architecture, such as memory and parallel computing. The most time consuming part of the formulation is identified and the critical roles of direct sparse and iterative solvers within the framework of the formulation are discussed. Experiments on several computer platforms using several complex test matrices are conducted using software based on the formulation. Small-scale structural examples are used to validate thc steps in the formulation and large-scale (l,000,000+ unknowns) duct acoustic examples are used to evaluate the ORIGIN 2000 processors, and a duster of 6 PCs (running under the Windows environment). Statistics show that the formulation is efficient in both sequential and parallel computing environmental and that the formulation is significantly faster and consumes less memory than that based on one of the best available commercialized parallel sparse solvers.

Lesson "Balance in Nature

NASA Astrophysics Data System (ADS)

Chapanova, V.

2012-04-01

Lesson "Balance in Nature" This simulation game-lesson (Balance in Nature) gives an opportunity for the students to show creativity, work independently, and to create models and ideas. It creates future-oriented thought connected to their experience, allowing them to propose solutions for global problems and personal responsibility for their activities. The class is divided in two teams. Each team chooses questions. 1. Question: Pollution in the environment. 2. Question: Care for nature and climate. The teams work on the chosen tasks. They make drafts, notes and formulate their solutions on small pieces of paper, explaining the impact on nature and society. They express their points of view using many different opinions. This generates alternative thoughts and results in creative solutions. With the new knowledge and positive behaviour defined, everybody realizes that they can do something positive towards nature and climate problems and the importance of individuals for solving global problems is evident. Our main goal is to recover the ecological balance, and everybody explains his or her own well-grounded opinions. In this work process the students obtain knowledge, skills and more responsible behaviour. This process, based on his or her own experience, dialogue and teamwork, helps the participant's self-development. Making the model "human↔ nature" expresses how human activities impact the natural Earth and how these impacts in turn affect society. Taking personal responsibility, we can reduce global warming and help the Earth. By helping nature we help ourselves. Teacher: Veselina Boycheva-Chapanova " Saint Patriarch Evtimii" Scholl Str. "Ivan Vazov"-19 Plovdiv Bulgaria

Wave-Particle Dualism in Action

NASA Astrophysics Data System (ADS)

Schleich, Wolfgang P.

The wave-particle dualism, that is the wave nature of particles and the particle nature of light together with the uncertainty relation of Werner Heisenberg and the principle of complementarity formulated by Niels Bohr represent pillars of quantum theory. We provide an introduction into these fascinating yet strange aspects of the microscopic world and summarize key experiments confirming these concepts so alien to our daily life.

Science Activities Pre-K-3: The Leaves are Falling in Rainbows.

ERIC Educational Resources Information Center

Knight, Michael; Graham, Terry

Opportunities to learn and discover surround a young child every day. The activities and ideas within this book have been formulated to encourage a child's natural curiosity and sense of wonder and to engage all the child's senses in learning and discovery. The activities focus on the child as a natural explorer and involve children in identifying…

Bridging the Gap in Hospital Preparedness

DTIC Science & Technology

2007-10-01

definition be formulated in areas and fields concerned with emergencies and disasters. Natural and manmade/ technological hazards should not automatically be...comments regarding this burden estimate or any other aspect ofthis collection ofinformation , including suggestions for reduc ng this brden to... technological hazards. Common types of natural hazards are, Bridging the Gap 14 but not limited to, geologic, atmospheric, seismic/volcanic, and

Motion estimation under location uncertainty for turbulent fluid flows

NASA Astrophysics Data System (ADS)

Cai, Shengze; Mémin, Etienne; Dérian, Pierre; Xu, Chao

2018-01-01

In this paper, we propose a novel optical flow formulation for estimating two-dimensional velocity fields from an image sequence depicting the evolution of a passive scalar transported by a fluid flow. This motion estimator relies on a stochastic representation of the flow allowing to incorporate naturally a notion of uncertainty in the flow measurement. In this context, the Eulerian fluid flow velocity field is decomposed into two components: a large-scale motion field and a small-scale uncertainty component. We define the small-scale component as a random field. Subsequently, the data term of the optical flow formulation is based on a stochastic transport equation, derived from the formalism under location uncertainty proposed in Mémin (Geophys Astrophys Fluid Dyn 108(2):119-146, 2014) and Resseguier et al. (Geophys Astrophys Fluid Dyn 111(3):149-176, 2017a). In addition, a specific regularization term built from the assumption of constant kinetic energy involves the very same diffusion tensor as the one appearing in the data transport term. Opposite to the classical motion estimators, this enables us to devise an optical flow method dedicated to fluid flows in which the regularization parameter has now a clear physical interpretation and can be easily estimated. Experimental evaluations are presented on both synthetic and real world image sequences. Results and comparisons indicate very good performance of the proposed formulation for turbulent flow motion estimation.

Plants and plant products with potential antipsoriatic activity--a review.

PubMed

Kaur, Arshdeep; Kumar, Suresh

2012-12-01

Psoriasis vulgaris is a hyper proliferative, autoimmune skin disorder affecting 1-3% of the world's population. The prescribed synthetic drugs for the treatment of psoriasis are associated with severe side effects, thus, researchers around the globe are searching for new, effective, and safer drugs from natural resources. The present review has been prepared with an objective to compile exhaustive literature on pharmacological reports on antipsoriatic plants, plant products, and formulations. An attempt has been made to incorporate chemical constituents (with structures) isolated from different plants responsible for antipsoriatic activity and their possible mechanism of actions in this review. The review has been compiled using references from major databases like Chemical Abstracts, Medicinal and Aromatic Plants Abstracts, PubMed, Scirus, Google scholar, Open J Gate, Scopus, Science Direct and Online Journals, and includes 127 references. A survey of literature revealed that extracts/fractions/isolates from 18 plants, 23 chemical constituents of plant origin and 40 plant-based formulations from various systems of medicine have been reported to possess antipsoriatic activity, and 37 antipsoriatic formulations containing plants have been patented. Preliminary antipsoriatic activity studies have been carried out on crude extracts of traditionally used and medicinally promising plants. Such plants need to be explored properly with a view to isolate antipsoriatic constituents, and to evaluate their possible mode of actions so that these plant drugs could be exploited properly as potential antipsoriatic drugs.

How to Spot Health Fraud

MedlinePlus

... Time-Tested or New-Found Treatment "This revolutionary innovation is formulated by using proven principles of natural ... and a decades-old remedy. Claims of an "innovation," "miracle cure," "exclusive product," or "new discovery" or " ...

Administration of resveratrol: What formulation solutions to bioavailability limitations?

PubMed

Amri, A; Chaumeil, J C; Sfar, S; Charrueau, C

2012-03-10

Resveratrol (3,5,4'-trihydroxystilbene), a naturally occurring polyphenol, has attracted considerable interest for its beneficial potentials for human health, which include anti-oxidant, anti-inflammatory, cardioprotective and anti-tumor activities. However, the in vivo biological effects of resveratrol appear strongly limited by its low bioavailability, which is a barrier to the development of therapeutic applications. In this context, an increasing number of recent studies have aimed at designing novel resveratrol formulations to overcome its poor solubility, limited stability, high metabolization and weak bioavailability. This review outlines physicochemical and pharmacokinetic limitations to resveratrol bioavailability, describes formulations tested for resveratrol administration, controlled release and targeting, and identifies future opportunities for resveratrol delivery. Copyright © 2011 Elsevier B.V. All rights reserved.

Nuclear staining with alum hematoxylin.

PubMed

Llewellyn, B D

2009-08-01

The hematoxylin and eosin stain is the most common method used in anatomic pathology, yet it is a method about which technologists ask numerous questions. Hematoxylin is a natural dye obtained from a tree originally found in Central America, and is easily converted into the dye hematein. This dye forms coordination compounds with mordant metals, such as aluminum, and the resulting lake attaches to cell nuclei. Regressive formulations contain a higher concentration of dye than progressive formulations and may also contain a lower concentration of mordant. The presence of an acid increases the life of the solution and in progressive solutions may also affect selectivity of staining. An appendix lists more than 60 hemalum formulations and the ratio of dye to mordant for each.

A solid-state NMR method to determine domain sizes in multi-component polymer formulations

NASA Astrophysics Data System (ADS)

Schlagnitweit, Judith; Tang, Mingxue; Baias, Maria; Richardson, Sara; Schantz, Staffan; Emsley, Lyndon

2015-12-01

Polymer domain sizes are related to many of the physical properties of polymers. Here we present a solid-state NMR experiment that is capable of measuring domain sizes in multi-component mixtures. The method combines selective excitation of carbon magnetization to isolate a specific component with proton spin diffusion to report on domain size. We demonstrate the method in the context of controlled release formulations, which represents one of today's challenges in pharmaceutical science. We show that we can measure domain sizes of interest in the different components of industrial pharmaceutical formulations at natural isotopic abundance containing various (modified) cellulose derivatives, such as microcrystalline cellulose matrixes that are film-coated with a mixture of ethyl cellulose (EC) and hydroxypropyl cellulose (HPC).

Comparative preclinical pharmacokinetics study of 3,3′-diindolylmethane formulations: is personalized treatment and targeted chemoprevention in the horizon?

PubMed Central

2013-01-01

Background 3,3′-Diindolylmethane (DIM) is known as an agent of natural origin that provides protection against different cancers due to the broad spectrum of its biological activities in vivo. However, this substance has a very poor biodistribution and absorption in animal tissues. This preclinical trial was conducted to evaluate the pharmacokinetics and bioavailability of various DIM formulations in animal model. Materials and methods The pharmacokinetic parameters of one crystalline DIM formulation and one liquid DIM formulation (oil solution) compared to non-formulated crystalline DIM (control) were tested in 200 rats. The formulations were orally administered to animals by gavage at doses of 200 mg/kg per DIM (crystalline DIM formulation and non-formulated crystalline DIM) and 0.1 mg/kg per DIM (DIM in oil solution). DIM plasma elimination was measured using HPLC method; after that, the area under the curve (AUC), relative bioavailability, and absolute bioavailability were estimated for two formulations in relation to non-formulated crystalline DIM. Results and conclusion The highest bioavailability was achieved by administering liquid DIM (oil solution), containing cod liver oil and polysorbate. The level of DIM in rat blood plasma was about fivefold higher, though the 2,000-fold lower dose was administered compared to crystalline DIM forms. The novel pharmacological DIM substance with high bioavailability may be considered as a promising targeted antitumor chemopreventive agent. It could be used to prevent breast and ovarian cancer development in patients with heterozygous inherited and sporadic BRCA1 gene mutations. Further preclinical and clinical trials are needed to prove this concept. PMID:24325835

Optimized zein nanospheres for improved oral bioavailability of atorvastatin

PubMed Central

Hashem, Fahima M; Al-Sawahli, Majid M; Nasr, Mohamed; Ahmed, Osama AA

2015-01-01

Background This work focuses on the development of atorvastatin utilizing zein, a natural, safe, and biocompatible polymer, as a nanosized formulation in order to overcome the poor oral bioavailability (12%) of the drug. Methods Twelve experimental runs of atorvastatin–zein nanosphere formula were formulated by a liquid–liquid phase separation method according to custom fractional factorial design to optimize the formulation variables. The factors studied were: weight % of zein to atorvastatin (X1), pH (X2), and stirring time (X3). Levels for each formulation variable were designed. The selected dependent variables were: mean particle size (Y1), zeta potential (Y2), drug loading efficiency (Y3), drug encapsulation efficiency (Y4), and yield (Y5). The optimized formulation was assayed for compatibility using an X-ray diffraction assay. In vitro diffusion of the optimized formulation was carried out. A pharmacokinetic study was also done to compare the plasma profile of the atorvastatin–zein nanosphere formulation versus atorvastatin oral suspension and the commercially available tablet. Results The optimized atorvastatin–zein formulation had a mean particle size of 183 nm, a loading efficiency of 14.86%, and an encapsulation efficiency of 29.71%. The in vitro dissolution assay displayed an initial burst effect, with a cumulative amount of atorvastatin released of 41.76% and 82.3% after 12 and 48 hours, respectively. In Wistar albino rats, the bioavailability of atorvastatin from the optimized atorvastatin–zein formulation was 3-fold greater than that from the atorvastatin suspension and the commercially available tablet. Conclusion The atorvastatin–zein nanosphere formulation improved the oral delivery and pharmacokinetic profile of atorvastatin by enhancing its oral bioavailability. PMID:26150716

Ephemeral profiles of prescription drug and formulation tampering: evolving pseudoscience on the Internet.

PubMed

Cone, Edward J

2006-06-01

The magnitude of non-therapeutic use, or misuse of prescription pharmaceuticals now rivals that of illicit drug abuse. Drug and formulation tampering enables misusers to administer higher doses by intended and non-intended routes. Perceived motives appear to be a combination of interests in achieving a faster onset and enhancing psychoactive effects. Narcotic analgesics, stimulants, and depressants are widely sought, examined, and tampered with for recreational use. This review examines tampering methods reported on the Internet for selected pharmaceutical products. The Internet provides broad and varied guidance on tampering methods that are specific to drug classes and unique formulations. Instructions are available on crushing, separating, purifying and chemically altering specific formulations to allow changes in dosage, route of administration, and time course of effects. Many pharmaceutical formulations contain features that serve as "barriers" to tampering. The nature and effectiveness of formulation barriers vary widely with many being overcome by adventurous misusers. Examples of successes and failures in tampering attempts are frequently described on Internet sites that support recreational drug use. Successful tampering methods that have widespread appeal evolve into recipes and become archived on multiple websites. Examples of tampering methods include: (1) how to separate narcotic drugs (codeine, hydrocodone, oxycodone) from excipients and non-desirable actives (aspirin, acetaminophen, ibuprofen); (2) overcoming time-release formulations (beads, layers, matrices); (3) removal of active drug from high-dose formulations (patches, pills); (4) alteration of dosage forms for alternate routes of administration. The development of successful formulations that inhibit or prevent drug/formulation tampering with drugs of abuse should take into consideration the scope and practice of tampering methods available to recreational drug users on the Internet.

Modeling of process of lifting power change of baker's yeast pressed depending on nature and quantity of introduced vegetable component

NASA Astrophysics Data System (ADS)

Belokurov, S. V.; Rodionova, N. S.; Belokurova, E. V.; Alexeeva, T. V.

2018-05-01

The work presents data on the effect of non-traditional powdered semi-finished products of plant origin: chokeberry, walnut partitions and sea buckthorn berries on the lifting power of baker's yeast. Various amounts of powdered semi-finished products of plant origin are introduced into the dough, directly at the stage of introducing the main components of the formulation, replacing them with some of the wheat flour. Studies have shown that the addition of small amounts of unconventional powdered plant-based semi-finished products (1 ... 5%) makes it possible to correct the lifting power of baking yeast, which, in consequence, affects the quality indicators of finished products. The paper presents a mathematical model of the change in the lift strength of baker's yeast, depending on the nature and amount of the powdered semi-finished product introduced.

Correlation Between Fracture Network Properties and Stress Variability in Geological Media

NASA Astrophysics Data System (ADS)

Lei, Qinghua; Gao, Ke

2018-05-01

We quantitatively investigate the stress variability in fractured geological media under tectonic stresses. The fracture systems studied include synthetic fracture networks following power law length scaling and natural fracture patterns based on outcrop mapping. The stress field is derived from a finite-discrete element model, and its variability is analyzed using a set of mathematical formulations that honor the tensorial nature of stress data. We show that local stress perturbation, quantified by the Euclidean distance of a local stress tensor to the mean stress tensor, has a positive, linear correlation with local fracture intensity, defined as the total fracture length per unit area within a local sampling window. We also evaluate the stress dispersion of the entire stress field using the effective variance, that is, a scalar-valued measure of the overall stress variability. The results show that a well-connected fracture system under a critically stressed state exhibits strong local and global stress variabilities.

A Role Calculus for ORM

NASA Astrophysics Data System (ADS)

Curland, Matthew; Halpin, Terry; Stirewalt, Kurt

A conceptual schema of an information system specifies the fact structures of interest as well as related business rules that are either constraints or derivation rules. Constraints restrict the possible or permitted states or state transitions, while derivation rules enable some facts to be derived from others. Graphical languages are commonly used to specify conceptual schemas, but often need to be supplemented by more expressive textual languages to capture additional business rules, as well as conceptual queries that enable conceptual models to be queried directly. This paper describes research to provide a role calculus to underpin textual languages for Object-Role Modeling (ORM), to enable business rules and queries to be formulated in a language intelligible to business users. The role-based nature of this calculus, which exploits the attribute-free nature of ORM, appears to offer significant advantages over other proposed approaches, especially in the area of semantic stability.