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Sample records for two-sided skin membranes

  1. Two-Sided Surface Oxidized Cellulose Membranes Modified with PEI: Preparation, Characterization and Application for Dyes Removal

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2017-09-01

    Full Text Available Porous regenerated cellulose (RC membranes were prepared with cotton linter pulp as a raw material. These membranes were first oxidized on both sides by a modified (2,2,6,6-tetramethylpiperidin-1-yloxyl (TEMPO oxidation system using a controlled oxidation reaction technique. Then, the oxidized RC membranes were functionalized with polyethylenimine (PEI via the glutaraldehyde crosslinking method to obtain bifunctional (carboxyl and amino porous RC membranes, as revealed by Fourier transform infrared spectroscopy (FT-IR, elemental analysis and zeta potential measurement. The scanning electron microscopy (SEM and the tests of the mechanical properties and permeability characteristics of modified RC membranes demonstrated that the porous structure and certain mechanical properties could be retained. The adsorption performance of the modified membranes towards dyes was subsequently investigated. The modified membranes displayed good adsorption capacities, rapid adsorption equilibrium and removal efficiencies towards both anionic (xylenol orange (XO and cationic (methylene blue (MB dyes, making them suitable bioadsorbents for wastewater treatment.

  2. Membrane properties for permeability testing: Skin versus synthetic membranes.

    Science.gov (United States)

    Haq, Anika; Dorrani, Mania; Goodyear, Benjamin; Joshi, Vivek; Michniak-Kohn, Bozena

    2018-03-25

    Synthetic membranes that are utilized in diffusion studies for topical and transdermal formulations are usually porous thin polymeric sheets for example cellulose acetate (CA) and polysulfones. In this study, the permeability of human skin was compared using two synthetic membranes: cellulose acetate and Strat-M® membrane and lipophilic and hydrophilic compounds either as saturated or formulated solutions as well as marketed dosage forms. Our data suggests that hydrophilic compounds have higher permeation in Strat-M membranes compared with lipophilic ones. High variation in permeability values, a typical property of biological membranes, was not observed with Strat-M. In addition, the permeability of Strat-M was closer to that of human skin than that of cellulose acetate (CA > Strat-M > Human skin). Our results suggest that Strat-M with little or no lot to lot variability can be applied in pilot studies of diffusion tests instead of human skin and is a better substitute than a cellulose acetate. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Fish skin as a model membrane: structure and characteristics.

    Science.gov (United States)

    Konrádsdóttir, Fífa; Loftsson, Thorsteinn; Sigfússon, Sigurdur Dadi

    2009-01-01

    Synthetic and cell-based membranes are frequently used during drug formulation development for the assessment of drug availability. However, most of the currently used membranes do not mimic mucosal membranes well, especially the aqueous mucous layer of the membranes. In this study we evaluated catfish (Anarichas lupus L) skin as a model membrane. Permeation of hydrocortisone, lidocaine hydrochloride, benzocaine, diethylstilbestrol, naproxen, picric acid and sodium nitrate through skin from a freshly caught catfish was determined in Franz diffusion cells. Both lipophilic and hydrophilic molecules permeate through catfish skin via hydrated channels or aqueous pores. No correlation was observed between the octanol/water partition coefficient of the permeating molecules and their permeability coefficient through the skin. Permeation through catfish skin was found to be diffusion controlled. The results suggest that permeation through the fish skin proceeds via a diffusion-controlled process, a process that is similar to drug permeation through the aqueous mucous layer of a mucosal membrane. In addition, the fish skin, with its collagen matrix structure, appears to possess similar properties to the eye sclera.

  4. Hydrocortisone Diffusion Through Synthetic Membrane, Mouse Skin, and Epiderm™ Cultured Skin.

    Science.gov (United States)

    Christensen, John Mark; Chuong, Monica Chang; Le, Hang; Pham, Loan; Bendas, Ehab

    2011-03-01

    OBJECTIVES: The penetration of hydrocortisone (HC) from six topical over-the-counter products along with one prescription cream through cultured normal human-derived epidermal keratinocytes (Epiderm™), mouse skin and synthetic nylon membrane was performed as well as the effect hydrating the skin by pre-washing was explored using the Upright Franz Cell. METHOD AND RESULTS: Permeation of HC through EpiDerm™, mouse skin and synthetic membrane was highest with the topical HC gel formulation with prewash treatment of the membranes among seven products evaluated, 198 ± 32 µg/cm(2), 746.32 ± 12.43 µg/cm(2), and 1882 ± 395.18 µg/cm(2), respectively. Pre-washing to hydrate the skin enhanced HC penetration through EpiDerm™ and mouse skin. The 24-hour HC released from topical gel with prewash treatment was 198.495 ± 32 µg/cm(2) and 746.32 ± 12.43 µg/cm(2) while without prewash, the 24-h HC released from topical gel was 67.2 ± 7.41 µg/cm(2) and 653.43 ± 85.62 µg/cm(2) though EpiDerm™ and mouse skin, respectively. HC penetration through synthetic membrane was ten times greater than through mouse skin and EpiDerm™. Generally, the shape, pattern, and rank order of HC diffusion from each commercial product was similar through each membrane.

  5. Basement membrane proteoglycans are of epithelial origin in rodent skin

    DEFF Research Database (Denmark)

    Yamane, Y; Yaoita, H; Couchman, J R

    1996-01-01

    . For in vivo experiments, pieces of newborn rat epidermis obtained by dispase treatment were grafted onto athymic nude mice. Three and six weeks after grafting, immunofluorescence analysis of the grafted skin was carried out, using monoclonal antibodies specific for rat basement membrane chondroitin sulfate...

  6. Price discrimination in two-sided markets

    Directory of Open Access Journals (Sweden)

    Kai Zhang

    2016-03-01

    Full Text Available The use of a price discrimination strategy is an important tool in competition. It can hurt firms and benefit consumers in a one-sided market. However, in two-sided markets, its primary goal is to attract more agents or increase profits. Here, the performance of a second-degree price discrimination strategy in the context of duopoly two-sided platforms is analysed. Two exogenous variables, which include the discount rate and the price discrimination threshold, are used in order to examine whether the price discrimination strategy could help two-sided platforms achieve their objective, which is to maximise their market value. Three cases are considered, and we demonstrate that the price discrimination strategy cannot attract more agents and at the same time increase the profits; a lower price discrimination threshold cannot ensure larger markets shares; a higher discount rate is detrimental to the profit of a platform. However, this is good for its market shares. Moreover, discriminative pricing increases the competition.

  7. Launching a Two-sided Platform

    OpenAIRE

    Solheim, Magnus Tovsen; Tovsen, Ole Kristoffer Solheim

    2017-01-01

    Two-sided platforms, such as Airbnb, Uber and eBay, have all revolutionized their industries. Despite having colossal potential, they are very difficult to launch. This is due to what s referred to as network effects, which imply that the value of the platform becomes larger as more people use it. Network effects lead to a chicken-or-egg-problem , where it is difficult to convince sellers to join if there are no buyers and vice versa, in addition to the need to reach a critical mass of users...

  8. Grammars with two-sided contexts

    Directory of Open Access Journals (Sweden)

    Mikhail Barash

    2014-05-01

    Full Text Available In a recent paper (M. Barash, A. Okhotin, "Defining contexts in context-free grammars", LATA 2012, the authors introduced an extension of the context-free grammars equipped with an operator for referring to the left context of the substring being defined. This paper proposes a more general model, in which context specifications may be two-sided, that is, both the left and the right contexts can be specified by the corresponding operators. The paper gives the definitions and establishes the basic theory of such grammars, leading to a normal form and a parsing algorithm working in time O(n^4, where n is the length of the input string.

  9. Dicationic alkylammonium bromide gemini surfactants. Membrane perturbation and skin irritation.

    Directory of Open Access Journals (Sweden)

    João A S Almeida

    Full Text Available Dicationic alkylammonium bromide gemini surfactants represent a class of amphiphiles potentially effective as skin permeation enhancers. However, only a limited number of studies has been dedicated to the evaluation of the respective cytotoxicity, and none directed to skin irritation endpoints. Supported on a cell viability study, the cytotoxicity of gemini surfactants of variable tail and spacer length was assessed. For this purpose, keratinocyte cells from human skin (NCTC 2544 cell line, frequently used as a model for skin irritation, were employed. The impact of the different gemini surfactants on the permeability and morphology of model vesicles was additionally investigated by measuring the leakage of calcein fluorescent dye and analyzing the NMR spectra of ³¹P, respectively. Detail on the interaction of gemini molecules with model membranes was also provided by a systematic differential scanning calorimetry (DSC and molecular dynamics (MD simulation. An irreversible impact on the viability of the NCTC 2544 cell line was observed for gemini concentrations higher than 25 mM, while no cytotoxicity was found for any of the surfactants in a concentration range up to 10 mM. A higher cytotoxicity was also found for gemini surfactants presenting longer spacer and shorter tails. The same trend was obtained in the calorimetric and permeability studies, with the gemini of longest spacer promoting the highest degree of membrane destabilization. Additional structural and dynamical characterization of the various systems, obtained by ³¹P NMR and MD, provide some insight on the relationship between the architecture of gemini surfactants and the respective perturbation mechanism.

  10. Agar/collagen membrane as skin dressing for wounds

    Energy Technology Data Exchange (ETDEWEB)

    Bao Lei; Yang Wei; Mao Xuan; Mou Shansong; Tang Shunqing [Biomedical Engineering Institute, Jinan University, Guangzhou (China)], E-mail: tshunqt@jnu.edu.cn, E-mail: tmuss@jnu.edu.cn

    2008-12-15

    Agar, a highly hydrophilic polymer, has a special gel property and favorable biocompatibility, but moderate intension strength in an aqueous condition and a low degradation rate. In order to tailor both properties of mechanical intension and degradation, type I collagen was composited with agar in a certain ratio by drying at 50 {sup 0}C or by a freeze-dry process. Glutaraldehyde was chosen as a crosslinking agent, and the most favorable condition for crosslinking was that the weight ratio of agar to glutaraldehyde was 66.7 and the pH value about 5. Dynamic mechanical analysis results showed that the single agar membrane had a modulus value between 640 MPa and 1064 MPa, but it was between 340 MPa and 819 MPa after being composited with type I collagen. It was discovered under an optical microscope that the pores were interconnected in the composite scaffolds instead of the honeycomb-like pores in a single type I collagen scaffold or the laminated gaps in a single agar scaffold. The results of an acute toxicity test disclosed that the composites were not toxic to mice although the composites were crosslinked with a certain concentration of glutaraldehyde. The results of gross examinations showed that when the composite membranes or scaffolds were applied to a repair rabbit skin lesion, the composites had a good repair effect without infection, liquid exudation or visible scar in the lesion covered with them. But in the control group, the autologous skin showed necrosis and there were a lot of scar tissues in the lesion site. H and E staining results showed that the repair tissue was similar to the normal one and very few scaffolds or membranes were left without degradation after 2 or 3 weeks. In conclusion, it is proved that type I collagen increases the toughness of the agar membrane, and the agar/type I collagen composites are promising biomaterials as wound dressings for healing burns or ulcers.

  11. Agar/collagen membrane as skin dressing for wounds

    International Nuclear Information System (INIS)

    Bao Lei; Yang Wei; Mao Xuan; Mou Shansong; Tang Shunqing

    2008-01-01

    Agar, a highly hydrophilic polymer, has a special gel property and favorable biocompatibility, but moderate intension strength in an aqueous condition and a low degradation rate. In order to tailor both properties of mechanical intension and degradation, type I collagen was composited with agar in a certain ratio by drying at 50 0 C or by a freeze-dry process. Glutaraldehyde was chosen as a crosslinking agent, and the most favorable condition for crosslinking was that the weight ratio of agar to glutaraldehyde was 66.7 and the pH value about 5. Dynamic mechanical analysis results showed that the single agar membrane had a modulus value between 640 MPa and 1064 MPa, but it was between 340 MPa and 819 MPa after being composited with type I collagen. It was discovered under an optical microscope that the pores were interconnected in the composite scaffolds instead of the honeycomb-like pores in a single type I collagen scaffold or the laminated gaps in a single agar scaffold. The results of an acute toxicity test disclosed that the composites were not toxic to mice although the composites were crosslinked with a certain concentration of glutaraldehyde. The results of gross examinations showed that when the composite membranes or scaffolds were applied to a repair rabbit skin lesion, the composites had a good repair effect without infection, liquid exudation or visible scar in the lesion covered with them. But in the control group, the autologous skin showed necrosis and there were a lot of scar tissues in the lesion site. H and E staining results showed that the repair tissue was similar to the normal one and very few scaffolds or membranes were left without degradation after 2 or 3 weeks. In conclusion, it is proved that type I collagen increases the toughness of the agar membrane, and the agar/type I collagen composites are promising biomaterials as wound dressings for healing burns or ulcers.

  12. Evaluation of a Silicone Membrane as an Alternative to Human Skin for Determining Skin Permeation Parameters of Chemical Compounds.

    Science.gov (United States)

    Uchida, Takashi; Yakumaru, Masafumi; Nishioka, Keisuke; Higashi, Yoshihiro; Sano, Tomohiko; Todo, Hiroaki; Sugibayashi, Kenji

    2016-01-01

    We evaluated the effectiveness of a silicone membrane as an alternative to human skin using the skin permeation parameters of chemical compounds. An in vitro permeation study using 15 model compounds was conducted, and permeation parameters comprising permeability coefficient (P), diffusion parameter (DL(-2)), and partition parameter (KL) were calculated from each permeation profile. Significant correlations were obtained in log P, log DL(-2), and log KL values between the silicone membrane and human skin. DL(-2) values of model compounds, except flurbiprofen, in the silicone membrane were independent of the lipophilicity of the model compounds and were 100-fold higher than those in human skin. For antipyrine and caffeine, which are hydrophilic, KL values in the silicone membrane were 100-fold lower than those in human skin, and P values, calculated as the product of a DL(-2) and KL, were similar. For lipophilic compounds, such as n-butyl paraben and flurbiprofen, KL values for silicone were similar to or 10-fold higher than those in human skin, and P values for silicone were 100-fold higher than those in human skin. Furthermore, for amphiphilic compounds with log Ko/w values from 0.5 to 3.5, KL values in the silicone membrane were 10-fold lower than those in human skin, and P values for silicone were 10-fold higher than those in human skin. The silicone membrane was useful as a human skin alternative in an in vitro skin permeation study. However, depending on the lipophilicity of the model compounds, some parameters may be over- or underestimated.

  13. Cdc42 expression in keratinocytes is required for the maintenance of the basement membrane in skin

    DEFF Research Database (Denmark)

    Wu, Xunwei; Quondamatteo, Fabio; Brakebusch, Cord

    2006-01-01

    , structure and number of hemidesomosomes were not significantly changed in the Cdc42 mutant skin compared with the control mice and no blister formation was observed in mutant skin. These data indicate that Cdc42 in keratinocytes is important for maintenance of the basement membrane of skin....... process, which requires directed secretion, deposition and organization of basement membrane components at the basal side of epithelial cells. In the current study, we analyzed the maintenance of skin basement membrane in mice with a keratinocyte-restricted deletion of the Cdc42 gene. In the absence...

  14. Evaluation of in vitro absorption, decontamination and desorption of organophosphorous compounds from skin and synthetic membranes.

    Science.gov (United States)

    Mircioiu, Constantin; Voicu, Victor A; Ionescu, Mihaela; Miron, Dalia S; Radulescu, Flavian S; Nicolescu, Adrian C

    2013-05-23

    Chemical warfare agents, such as soman, and pesticides, such as chlorpyrifos, dichlorvos or malathion, are toxic organophosphorous compounds (OPCs) that are readily absorbed by the skin. Decontamination using solvents or surfactants may modify the cornified layer - the skin's main barrier against xenobiotic penetration. Thus, effective skin decontamination with fewer side effects is desired. We determined the membrane absorption, decontamination and desorption of toxic OPCs using human skin and synthetic membrane (cuprophane, cellulose acetate, methyl ethyl cellulose, acetophane and nylon) models, and estimated the efficacy of adsorptive powders (bentonite and magnesium trisilicate) at inhibiting this transfer. Using validated flow-through and static diffusion cell and HPLC methods, we found that the transfer of OPCs depends on their membrane affinity. The chlorpyrifos transfer decreased with a decrease in the membrane hydrophilicity, and that of malathion across hydrophilic membranes was less than half of that across hydrophobic membranes. We reliably modeled the toxicant transfer through the skin and synthetic membranes as first-order kinetic and/or square root law transfer processes, suggesting a potential application of synthetic membranes for predicting percutaneous absorption of OPCs. All tested adsorptive powders, applied either alone or as mixtures, significantly reduced the toxicant amount transferred across all membrane models, suggesting a potential therapeutic application with fewer later undesired effects on intact skin. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  15. Numerical tension adjustment of x-ray membrane to represent goat skin kompang

    Science.gov (United States)

    Siswanto, Waluyo Adi; Abdullah, Muhammad Syiddiq Bin

    2017-04-01

    This paper presents a numerical membrane model of traditional musical instrument kompang that will be used to find the parameter of membrane tension of x-ray membrane representing the classical goat-skin membrane of kompang. In this study, the experiment towards the kompang is first conducted in an acoustical anechoic enclosure and in parallel a mathematical model of the kompang membrane is developed to simulate the vibration of the kompang membrane in polar coordinate by implementing Fourier-Bessel wave function. The wave equation in polar direction in mode 0,1 is applied to provide the corresponding natural frequencies of the circular membrane. The value of initial and boundary conditions in the function is determined from experiment to allow the correct development of numerical equation. The numerical mathematical model is coded in SMath for the accurate numerical analysis as well as the plotting tool. Two kompang membrane cases with different membrane materials, i.e. goat skin and x-ray film membranes with fixed radius of 0.1 m are used in the experiment. An alternative of kompang's membrane made of x-ray film with the appropriate tension setting can be used to represent the sound of traditional goat-skin kompang. The tension setting of the membrane to resemble the goat-skin is 24N. An effective numerical tool has been develop to help kompang maker to set the tension of x-ray membrane. In the future application, any tradional kompang with different size can be replaced by another membrane material if the tension is set to the correct tension value. The developed numerical tool is useful and handy to calculate the tension of the alternative membrane material.

  16. Ultrathin-skinned asymmetric membranes by immiscible solvents treatment

    Science.gov (United States)

    Friesen, Dwayne T.; Babcock, Walter C.

    1989-01-01

    Improved semipermeable asymmetric fluid separation membranes useful in gas, vapor and liquid separations are disclosed. The membranes are prepared by substantially filling the pores of asymmetric cellulosic semipermeable membranes having a finely porous layer on one side thereof with a water immiscible organic liquid, followed by contacting the finely porous layer with water.

  17. Double-Skinned Forward Osmosis Membranes for Reducing Internal Concentration Polarization within the Porous Sublayer

    KAUST Repository

    Wang, Kai Yu

    2010-05-19

    A scheme to fabricate forward osmosis membranes comprising a highly porous sublayer sandwiched between two selective skin layers via phase inversion was proposed. One severe deficiency of existing composite and asymmetric membranes used in forward osmosis is the presence of unfavorable internal concentration polarization within the porous support layer that hinders both (i) separation (salt flux) and (ii) the performance (water flux). The double skin layers of the tailored membrane may mitigate the internal concentration polarization by preventing the salt and other solutes in the draw solution from penetrating into the membrane porous support. The prototype double-skinned cellulose acetate membrane displayed a water flux of 48.2 L·m-2·h -1 and lower reverse salt transport of 6.5 g·m -2·h-1 using 5.0 M MgCl2 as the draw solution in a forward osmosis process performed at 22 °C. This can be attributed to the effective salt rejection by the double skin layers and the low water transport resistance within the porous support layer. The prospects of utilizing the double-selective layer membranes may have potential application in forward osmosis for desalination. This study may help pave the way to improve the membrane design for the forward osmosis process. © 2010 American Chemical Society.

  18. Double-Skinned Forward Osmosis Membranes for Reducing Internal Concentration Polarization within the Porous Sublayer

    KAUST Repository

    Wang, Kai Yu; Ong, Rui Chin; Chung, Tai-Shung

    2010-01-01

    A scheme to fabricate forward osmosis membranes comprising a highly porous sublayer sandwiched between two selective skin layers via phase inversion was proposed. One severe deficiency of existing composite and asymmetric membranes used in forward osmosis is the presence of unfavorable internal concentration polarization within the porous support layer that hinders both (i) separation (salt flux) and (ii) the performance (water flux). The double skin layers of the tailored membrane may mitigate the internal concentration polarization by preventing the salt and other solutes in the draw solution from penetrating into the membrane porous support. The prototype double-skinned cellulose acetate membrane displayed a water flux of 48.2 L·m-2·h -1 and lower reverse salt transport of 6.5 g·m -2·h-1 using 5.0 M MgCl2 as the draw solution in a forward osmosis process performed at 22 °C. This can be attributed to the effective salt rejection by the double skin layers and the low water transport resistance within the porous support layer. The prospects of utilizing the double-selective layer membranes may have potential application in forward osmosis for desalination. This study may help pave the way to improve the membrane design for the forward osmosis process. © 2010 American Chemical Society.

  19. Harmony Search for Balancing Two-sided Assembly Lines

    Directory of Open Access Journals (Sweden)

    Hindriyanto Dwi Purnomo

    2012-01-01

    Full Text Available Two-sided assembly lines balancing problems are important problem for large-sized products such as cars and buses, in which, tasks operations can be performed in the two sides of the line. In this paper, Harmony Search algorithm is proposed to solve two-sided assembly lines balancing problems type-I (TALBP-I. The proposed method adopts the COMSOAL heuristic and specific features of TALBP in the Harmony operators – the harmony memory consideration, random selection and pitch adjustment – in order to maintain the local and global search. The proposed method is evaluated based on 6 benchmark problems that are commonly used in TALBP. The experiment results show that the proposed method work well and produces better solution than the heuristic method and genetic algorithm.

  20. Novice in Secondary School--The Coin Has Two Sides

    Science.gov (United States)

    Ulvik, Marit; Smith, Kari; Helleve, Ingrid

    2009-01-01

    The aim of this study is to gain an insight into novice teachers' diverse experiences. The study is conducted among nine beginning teachers in upper secondary school in Norway, and the research instrument was semi structured interviews. The main findings indicate that there are two sides of the coin of being a new teacher, positive as well as less…

  1. Statistical Significance and Effect Size: Two Sides of a Coin.

    Science.gov (United States)

    Fan, Xitao

    This paper suggests that statistical significance testing and effect size are two sides of the same coin; they complement each other, but do not substitute for one another. Good research practice requires that both should be taken into consideration to make sound quantitative decisions. A Monte Carlo simulation experiment was conducted, and a…

  2. Upward Pricing Pressure in Two-Sided Markets

    NARCIS (Netherlands)

    Affeldt, P.; Filistrucchi, L.; Klein, T.J.

    2012-01-01

    Abstract: Pricing pressure indices have recently been proposed as alternative screening devices for horizontal mergers involving differentiated products. We extend the concept of Upward Pricing Pressure (UPP) proposed by Farrell and Shapiro (2010) to two-sided markets. Examples of such markets are

  3. Upward pricing pressure in two-sided markets

    NARCIS (Netherlands)

    Affeldt, P.; Filistrucchi, L.; Klein, T.J.

    2013-01-01

    Measuring upward pricing pressure (UPP) has recently been proposed by Farrell and Shapiro (2010) as an alternative screening device for horizontal mergers. We extend the concept of UPP to two-sided markets. Examples of such markets are the newspaper market, where the demand for advertising is

  4. Hollow fiber ultrafiltration membranes with microstructured inner skin

    NARCIS (Netherlands)

    Culfaz, P.Z.; Wessling, Matthias; Lammertink, Rob G.H.

    2011-01-01

    Hollow fiber membranes with microstructured inner surfaces were fabricated from a PES/PVP blend using a spinneret with a microstructured needle. The effect of spinning parameters such as polymer dope flow rate, bore liquid flowrate, air gap and take-up speed on the microstructure and shape of the

  5. Highly permeable double-skinned forward osmosis membranes for anti-fouling in the emulsified oil-water separation process

    KAUST Repository

    Duong, Hoang Hanh Phuoc; Chung, Neal Tai-Shung; Wei, Shawn; Irish, Lana

    2014-01-01

    Forward osmosis (FO) has attracted wide attention in recent years. However, the FO performance may be restricted due to internal concentration polarization (ICP) and fast fouling propensity that occurs in the membrane sublayer. Particularly, these problems significantly affect the membrane performance when treating highly contaminated oily wastewater. Recently, double-skinned flat sheet cellulose acetate (CA) membranes consisting of two selective skins via the phase inversion method have demonstrated less ICP and fouling propensity over typical single-skinned membranes. However, these membranes exhibit low water fluxes of <12 LMH under 2 M NaCl draw solution. Therefore, a novel double-skinned FO membrane with a high water flux has been aimed for in this study for emulsified oil-water treatment. The double-skinned FO membrane comprises a fully porous sublayer sandwiched between (i) a truly dense skin for salt rejection and (ii) a fairly loose dense skin for emulsified oil particle rejection. The former dense skin is a polyamide synthesized via interfacial polymerization, while the latter one is a self-assembled sulfonated pentablock copolymer (Nexar copolymer) layer. The resultant double-skinned membrane exhibits a high water flux of 17.2 LMH and a low reverse salt transport of 4.85 gMH using 0.5 M NaCl as the draw solution and DI water as the feed. The double-skinned membrane outperforms the single-skinned membrane with much lower fouling propensity for emulsified oil-water separation. © 2014 American Chemical Society.

  6. Highly permeable double-skinned forward osmosis membranes for anti-fouling in the emulsified oil-water separation process

    KAUST Repository

    Duong, Hoang Hanh Phuoc

    2014-04-15

    Forward osmosis (FO) has attracted wide attention in recent years. However, the FO performance may be restricted due to internal concentration polarization (ICP) and fast fouling propensity that occurs in the membrane sublayer. Particularly, these problems significantly affect the membrane performance when treating highly contaminated oily wastewater. Recently, double-skinned flat sheet cellulose acetate (CA) membranes consisting of two selective skins via the phase inversion method have demonstrated less ICP and fouling propensity over typical single-skinned membranes. However, these membranes exhibit low water fluxes of <12 LMH under 2 M NaCl draw solution. Therefore, a novel double-skinned FO membrane with a high water flux has been aimed for in this study for emulsified oil-water treatment. The double-skinned FO membrane comprises a fully porous sublayer sandwiched between (i) a truly dense skin for salt rejection and (ii) a fairly loose dense skin for emulsified oil particle rejection. The former dense skin is a polyamide synthesized via interfacial polymerization, while the latter one is a self-assembled sulfonated pentablock copolymer (Nexar copolymer) layer. The resultant double-skinned membrane exhibits a high water flux of 17.2 LMH and a low reverse salt transport of 4.85 gMH using 0.5 M NaCl as the draw solution and DI water as the feed. The double-skinned membrane outperforms the single-skinned membrane with much lower fouling propensity for emulsified oil-water separation. © 2014 American Chemical Society.

  7. SAMPA: A free software tool for skin and membrane permeation data analysis.

    Science.gov (United States)

    Bezrouk, Aleš; Fiala, Zdeněk; Kotingová, Lenka; Krulichová, Iva Selke; Kopečná, Monika; Vávrová, Kateřina

    2017-10-01

    Skin and membrane permeation experiments comprise an important step in the development of a transdermal or topical formulation or toxicological risk assessment. The standard method for analyzing these data relies on the linear part of a permeation profile. However, it is difficult to objectively determine when the profile becomes linear, or the experiment duration may be insufficient to reach a maximum or steady state. Here, we present a software tool for Skin And Membrane Permeation data Analysis, SAMPA, that is easy to use and overcomes several of these difficulties. The SAMPA method and software have been validated on in vitro and in vivo permeation data on human, pig and rat skin and model stratum corneum lipid membranes using compounds that range from highly lipophilic polycyclic aromatic hydrocarbons to highly hydrophilic antiviral drug, with and without two permeation enhancers. The SAMPA performance was compared with the standard method using a linear part of the permeation profile and a complex mathematical model. SAMPA is a user-friendly, open-source software tool for analyzing the data obtained from skin and membrane permeation experiments. It runs on a Microsoft Windows platform and is freely available as a Supporting file to this article. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Heat transfer from two-side heated helical channels

    International Nuclear Information System (INIS)

    Shimonis, V.; Ragaishis, V.; Poshkas, P.

    1995-01-01

    Experimental results are presented on the heat transfer from two-side heated helical channels to gas (air) flows. The study covered six configurations and wide ranges of geometrical (D/h=5.5 to 84.2) and performance (Re=10 3 to 2*10 5 ) parameters. Under the influence of Re and of the channel curvature, the heat transfer from both the convex and the concave surfaces for two-side heating (q w1 ≅ q w2 ) is augmented by 20-30% over one-side heating. Improved relations to predict the critical values of Reynolds Re cr1 and Re cr2 are suggested. They enable more exact predictions of the heat transfer from convex surface in transient flows for one-side heating. The relation for annular channels is suggested for the turbulent heat transfer from the convex and concave surfaces of two-side heated helical channels. It can be adapted by introducing earlier expresions for one-side heated helical channels. (author). 6 refs., 2 tabs., 3 figs

  9. Imageology and clinical examination: Two sides of the same coin

    Directory of Open Access Journals (Sweden)

    Deepa Das

    2011-01-01

    Full Text Available The continuous and rapid transition of techniques from research lab into clinical practice has been the pattern of development in radiology and imaging, and this has put the concept of clinical imaging into a different perspective. From a passive role of pattern recognition, distinguishing a radiograph from normal to abnormal, the task of a radiologist today has been elevated to reporting a comprehensive clinical imaging assay, giving information at a level profound enough to be useful for scientists working in allied fields. A peep into the literature shows how radiological and clinical examination can be two sides of the same coin.

  10. Peace and development: two sides of the same coin?

    Directory of Open Access Journals (Sweden)

    Viveros Tafur, Memphis Ronald

    2015-07-01

    Full Text Available There is the notion that peace and development are positively correlated, that peace drives development and that development drives peace, for Galtung (1985: 147 Peace and Development should be regarded as two sides of the same coin and considers development in relation to peace. This paper shows that peace and development are uncorrelated in several countries where there is peace without development or development without peace. The use of quantitative models as a tool for the analysis is a plus for the findings because most of the related theories are qualitative.

  11. Population and housing: A two-sided relationship

    Directory of Open Access Journals (Sweden)

    Clara H. Mulder

    2006-11-01

    Full Text Available In this paper I explore the relationship between population and housing. I argue that this relationship is two-sided. On the one hand, the size of a population, and particularly the number of households, determines the demand for housing. On the other hand, the availability of suitable and affordable housing may attract certain categories of migrants. It also influences young people's opportunities to leave the parental home, marry or cohabit, and have children. Furthermore, home-ownership hampers residential mobility and migration by binding people to a place.

  12. The properties of connective tissue membrane and pig skin as raw materials for cooked sausage.

    Science.gov (United States)

    Puolanne, E; Ruusunen, M

    1981-09-01

    Pig skin and epimysial membrane from young bulls were comminuted in a colloid grinder and mixed with water and additives. The resultant mixture was heated in a water bath to give an internal temperature of 72°C, and centrifuged while still hot. Such variations in the amount of water added, the salt content, the phosphate content and the pH value as are possible in cooked sausage heated to over 65°C during processing did not cause marked changes in the amount of water bound by the connective tissues, the amount of dissolved protein or the gel strength of the liquid released from the connective tissues. As the temperature rose the amount of bound water dropped, but the amount of dissolved protein and the gel strength increased. The liquid released from the connective tissue membranes formed a gel at 32°C and re-melted at 49°C. For pig skin, the corresponding temperatures were 23°C and 47°C. On the basis of this study it appears that connective tissue may be important for the water-binding capacity and firmness of cold sausage. The connective tissue membranes obtained from young bulls and pig skin are of roughly equal value in this respect, although the gel formed from connective tissue membrane is tougher. Copyright © 1981. Published by Elsevier Ltd.

  13. A Diffusion Model for Two-sided Service Systems

    Science.gov (United States)

    Homma, Koichi; Yano, Koujin; Funabashi, Motohisa

    A diffusion model is proposed for two-sided service systems. ‘Two-sided’ refers to the existence of an economic network effect between two different and interrelated groups, e.g., card holders and merchants in an electronic money service. The service benefit for a member of one side depends on the number and quality of the members on the other side. A mathematical model by J. H. Rohlfs explains the network (or bandwagon) effect of communications services. In Rohlfs' model, only the users' group exists and the model is one-sided. This paper extends Rohlfs' model to a two-sided model. We propose, first, a micro model that explains individual behavior in regard to service subscription of both sides and a computational method that drives the proposed model. Second, we develop macro models with two diffusion-rate variables by simplifying the micro model. As a case study, we apply the models to an electronic money service and discuss the simulation results and actual statistics.

  14. Utilization of Shrimp Skin Waste (Sea Lobster) As Raw Material for the Membrane Filtration

    International Nuclear Information System (INIS)

    Rupiasih, Ni Nyoman; Windari, Putri; Sumadiyasa, Made; Suyanto, Hery

    2017-01-01

    In view of the increasing littering of the sea banks by shells of crustaceans, a study was carried out to investigate the extraction and characterization of chitosan from skin waste of sea lobster i.e. ‘Bamboo Lobster’ ( Panulirus versicolor ). Chitosan was extracted using conventional methods such as pretreatment, demineralization, deprotienization, and deacetylation. The result showed that the degree of deacetylation of chitosan obtained is 70.02%. The FTIR spectra of the chitosan gave a characteristic of –NH 2 band at 3447 cm –1 and carbonyl group band at 1655 cm −1 . This chitosan has been used to prepare membrane. The chitosan membrane 2% has been prepared using phase inversion method with precipitation by solvent evaporation. The membranes were characterized by FTIR spectrophotometer, Nova 1200e using BJH method, and filtration method. The results show that thickness of the membrane is about 134 μm. The FTIR spectra show that functional groups present in the membrane are -NH, -CH, C=O, and -OH. Using BJH method obtained that the pore diameter is 3.382 nm with pore density is 8.95 x 10 5 pores/m 3 . By filtration method obtained that pure water flux (PWF) of the membrane are 386.662 and 489.627 1/m 2 .h at pressure 80-85 kPa and 90-100 kPa, respectively. These results show that skin waste of sea lobster was discovered as a raw material to prepare chitosan membrane. The membrane obtained is belonged to mesoporous group which may use in microfiltration process. (paper)

  15. Skin Mast Cell Promotion in Random Skin Flaps in Rats using Bone Marrow Mesenchymal Stem Cells and Amniotic Membrane

    Science.gov (United States)

    Chehelcheraghi, Farzaneh; Abbaszadeh, Abolfazl; Tavafi, Magid

    2018-03-06

    Skin flap procedures are employed in plastic surgery, but failure can lead to necrosis of the flap. Studies have used bone marrow mesenchymal stem cells (BM-MSCs) to improve flap viability. BM-MSCs and acellular amniotic membrane (AAM) have been introduced as alternatives. The objective of this study was to evaluate the effect of BM-MSCs and AAM on mast cells of random skin flaps (RSF) in rats. RSFs (80 × 30 mm) were created on 40 rats that were randomly assigned to one of four groups, including (I) AAM, (II) BM-MSCs, (III) BM-MSCs/AAM, and (IV) saline (control). Transplantation was carried out during the procedure (zero day). Flap necrosis was observed on day 7, and skin samples were collected from the transition line of the flap to evaluate the total number and types of mast cells. The development and the total number of mast cells were related to the development of capillaries. The results of one-way ANOVA indicated that there was no statistically significant difference between the mean numbers of mast cell types for different study groups. However, the difference between the total number of mast cells in the study groups was statistically significant (p = 0.001). The present study suggests that the use of AAM/BM-MSCs can improve the total number of mast cells and accelerate the growth of capillaries at the transient site in RSFs in rats.

  16. Membrane damage induced in cultured human skin fibroblasts by UVA irradiation

    International Nuclear Information System (INIS)

    Gaboriau, F.; Morliere, P.; Marquis, I.; Moysan, A.; Geze, M.; Dubertret, L.

    1993-01-01

    Irradiation of cultured human skin fibroblasts with ultraviolet light from 320 to 400 nm (UVA) leads to a decrease in the membrane fluidity exemplified by an enhanced fluorescence anisotropy of the lipophilic fluorescent probe 1-[4-trimethylamino)-phenyl]-6-phenylhexa-1,3,5-triene. This UVA-induced decrease in fluidity is associated with lactate dehydrogenase leakage in the supernatant. Vitamin E, an inhibitor of lipid peroxidation, exerts a protective effect on both phenomena. Therefore, this UVA-induced damage in membrane properties may be related to lipid peroxidation processes. Moreover, exponentially growing cells are more sensitive to these UVA-induced alterations than confluent cells. (Author)

  17. Protein nanocoatings on synthetic polymeric nanofibrous membranes designed as carriers for skin cells.

    Science.gov (United States)

    Bacakova, Marketa; Pajorova, Julia; Stranska, Denisa; Hadraba, Daniel; Lopot, Frantisek; Riedel, Tomas; Brynda, Eduard; Zaloudkova, Margit; Bacakova, Lucie

    2017-01-01

    Protein-coated resorbable synthetic polymeric nanofibrous membranes are promising for the fabrication of advanced skin substitutes. We fabricated electrospun polylactic acid and poly(lactide- co -glycolic acid) nanofibrous membranes and coated them with fibrin or collagen I. Fibronectin was attached to a fibrin or collagen nanocoating, in order further to enhance the cell adhesion and spreading. Fibrin regularly formed a coating around individual nanofibers in the membranes, and also formed a thin noncontinuous nanofibrous mesh on top of the membranes. Collagen also coated most of the fibers of the membrane and randomly created a soft gel on the membrane surface. Fibronectin predominantly adsorbed onto a thin fibrin mesh or a collagen gel, and formed a thin nanofibrous structure. Fibrin nanocoating greatly improved the attachment, spreading, and proliferation of human dermal fibroblasts, whereas collagen nanocoating had a positive influence on the behavior of human HaCaT keratinocytes. In addition, fibrin stimulated the fibroblasts to synthesize fibronectin and to deposit it as an extracellular matrix. Fibrin coating also showed a tendency to improve the ultimate tensile strength of the nanofibrous membranes. Fibronectin attached to fibrin or to a collagen coating further enhanced the adhesion, spreading, and proliferation of both cell types.

  18. A co-cultured skin model based on cell support membranes

    International Nuclear Information System (INIS)

    Dai, N.-T.; Yeh, M.-K.; Liu, Demeral David; Adams, E.F.; Chiang, C.-H.; Yen, C.-Y.; Shih, C.-M.; Sytwu, H.-K.; Chen, Tim-Mo; Wang, H.-J.; Williamson, M.R.; Coombes, A.G.A.

    2005-01-01

    Tissue engineering of skin based on collagen: PCL biocomposites using a designed co-culture system is reported. The collagen: PCL biocomposites having collagen: PCL (w/w) ratios of 1:4, 1:8, and 1:20 have been proven to be biocompatible materials to support both adult normal human epidermal Keratinocyte (NHEK) and mouse 3T3 fibroblast growth in cell culture, respectively, by Dai, Coombes, et al. in 2004. Films of collagen: PCL biocomposites were prepared using non-crosslinking method by impregnation of lyophilized collagen mats with PCL/dichloromethane solutions followed by solvent evaporation. To mimic the dermal/epidermal structure of skin, the 1:20 collagen: PCL biocomposites were selected for a feasibility study of a designed co-culture technique that would subsequently be used for preparing fibroblast/biocomposite/keratinocyte skin models. A 55.3% increase in cell number was measured in the designed co-culture system when fibroblasts were seeded on both sides of a biocomposite film compared with cell culture on one surface of the biocomposite in the feasibility study. The co-culture of human keratinocytes and 3T3 fibroblasts on each side of the membrane was therefore studied using the same co-culture system by growing keratinocytes on the top surface of membrane for 3 days and 3T3 fibroblasts underneath the membrane for 6 days. Scanning electron microscopy (SEM) and immunohistochemistry assay revealed good cell attachment and proliferation of both human keratinocytes and 3T3 fibroblasts with these two types of cells isolated well on each side of the membrane. Using a modified co-culture technique, a co-cultured skin model presenting a confluent epidermal sheet on one side of the biocomposite film and fibroblasts populated on the other side of the film was developed successfully in co-culture system for 28 days under investigations by SEM and immunohistochemistry assay. Thus, the design of a co-culture system based on 1:20 (w/w) collagen: PCL biocomposite

  19. Permeability Barrier and Microstructure of Skin Lipid Membrane Models of Impaired Glucosylceramide Processing

    OpenAIRE

    Sochorov?, Michaela; Sta?kov?, Kl?ra; Pullmannov?, Petra; Kov??ik, Andrej; Zbytovsk?, Jarmila; V?vrov?, Kate?ina

    2017-01-01

    Ceramide (Cer) release from glucosylceramides (GlcCer) is critical for the formation of the skin permeability barrier. Changes in ?-glucocerebrosidase (GlcCer?ase) activity lead to diminished Cer, GlcCer accumulation and structural defects in SC lipid lamellae; however, the molecular basis for this impairment is not clear. We investigated impaired GlcCer-to-Cer processing in human Cer membranes to determine the physicochemical properties responsible for the barrier defects. Minor impairment (...

  20. Skin Membrane Electrical Impedance Properties under the Influence of a Varying Water Gradient

    Science.gov (United States)

    Björklund, Sebastian; Ruzgas, Tautgirdas; Nowacka, Agnieszka; Dahi, Ihab; Topgaard, Daniel; Sparr, Emma; Engblom, Johan

    2013-01-01

    The stratum corneum (SC) is an effective permeability barrier. One strategy to increase drug delivery across skin is to increase the hydration. A detailed description of how hydration affects skin permeability requires characterization of both macroscopic and molecular properties and how they respond to hydration. We explore this issue by performing impedance experiments on excised skin membranes in the frequency range 1 Hz to 0.2 MHz under the influence of a varying gradient in water activity (aw). Hydration/dehydration induces reversible changes of membrane resistance and effective capacitance. On average, the membrane resistance is 14 times lower and the effective capacitance is 1.5 times higher when the outermost SC membrane is exposed to hydrating conditions (aw = 0.992), as compared to the case of more dehydrating conditions (aw = 0.826). Molecular insight into the hydration effects on the SC components is provided by natural-abundance 13C polarization transfer solid-state NMR and x-ray diffraction under similar hydration conditions. Hydration has a significant effect on the dynamics of the keratin filament terminals and increases the interchain spacing of the filaments. The SC lipids are organized into lamellar structures with ∼ 12.6 nm spacing and hexagonal hydrocarbon chain packing with mainly all-trans configuration of the acyl chains, irrespective of hydration state. Subtle changes in the dynamics of the lipids due to mobilization and incorporation of cholesterol and long-chain lipid species into the fluid lipid fraction is suggested to occur upon hydration, which can explain the changes of the impedance response. The results presented here provide information that is useful in explaining the effect of hydration on skin permeability. PMID:23790372

  1. Interpenetrating network hydrogel membranes of sodium alginate and poly(vinyl alcohol) for controlled release of prazosin hydrochloride through skin.

    Science.gov (United States)

    Kulkarni, Raghavendra V; Sreedhar, V; Mutalik, Srinivas; Setty, C Mallikarjun; Sa, Biswanath

    2010-11-01

    Interpenetrating network (IPN) hydrogel membranes of sodium alginate (SA) and poly(vinyl alcohol) (PVA) were prepared by solvent casting method for transdermal delivery of an anti-hypertensive drug, prazosin hydrochloride. The prepared membranes were thin, flexible and smooth. The X-ray diffraction studies indicated the amorphous dispersion of drug in the membranes. Differential scanning calorimetric analysis confirmed the IPN formation and suggests that the membrane stiffness increases with increased concentration of glutaraldehyde (GA) in the membranes. All the membranes were permeable to water vapors depending upon the extent of cross-linking. The in vitro drug release study was performed through excised rat abdominal skin; drug release depends on the concentrations of GA in membranes. The IPN membranes extended drug release up to 24 h, while SA and PVA membranes discharged the drug quickly. The primary skin irritation and skin histopathology study indicated that the prepared IPN membranes were less irritant and safe for skin application. Copyright © 2010 Elsevier B.V. All rights reserved.

  2. Neutrophils in Cancer: Two Sides of the Same Coin.

    Science.gov (United States)

    Uribe-Querol, Eileen; Rosales, Carlos

    2015-01-01

    Neutrophils are the most abundant leukocytes in blood and are considered to be the first line of defense during inflammation and infections. In addition, neutrophils are also found infiltrating many types of tumors. Tumor-associated neutrophils (TANs) have relevant roles in malignant disease. Indeed neutrophils may be potent antitumor effector cells. However, increasing clinical evidence shows TANs correlate with poor prognosis. The tumor microenvironment controls neutrophil recruitment and in turn TANs help tumor progression. Hence, TANs can be beneficial or detrimental to the host. It is the purpose of this review to highlight these two sides of the neutrophil coin in cancer and to describe recent studies that provide some light on the mechanisms for neutrophil recruitment to the tumor, for neutrophils supporting tumor progression, and for neutrophil activation to enhance their antitumor functions.

  3. Neutrophils in Cancer: Two Sides of the Same Coin

    Directory of Open Access Journals (Sweden)

    Eileen Uribe-Querol

    2015-01-01

    Full Text Available Neutrophils are the most abundant leukocytes in blood and are considered to be the first line of defense during inflammation and infections. In addition, neutrophils are also found infiltrating many types of tumors. Tumor-associated neutrophils (TANs have relevant roles in malignant disease. Indeed neutrophils may be potent antitumor effector cells. However, increasing clinical evidence shows TANs correlate with poor prognosis. The tumor microenvironment controls neutrophil recruitment and in turn TANs help tumor progression. Hence, TANs can be beneficial or detrimental to the host. It is the purpose of this review to highlight these two sides of the neutrophil coin in cancer and to describe recent studies that provide some light on the mechanisms for neutrophil recruitment to the tumor, for neutrophils supporting tumor progression, and for neutrophil activation to enhance their antitumor functions.

  4. MATHEMATICAL SIMULATION OF CONCURRENT TWO-SIDED LENS PROCESSING

    Directory of Open Access Journals (Sweden)

    A. S. Kozeruk

    2015-01-01

    Full Text Available The purpose of the paper is to modernize technology for obtaining high-accuracy lenses with fine centre. Presently their operating surfaces are fixed  to an accessory with the help of adhesive substance that leads to elastic deformation in glass and causes local errors in lens parts.A mathematical model for concurrent two-sided processing of high-accuracy optical parts with spherical surfaces has been developed in the paper. The paper presents analytical expressions that permit to calculate sliding speed at any point on the processed spherical surface depending on type and value of technological equipment settings. Calculation of parameter Q = Pv in a diametric section of the convexo-concave lens has been carried out while using these expressions together with functional dependence of pressure on contact zone еarea of tool and part bedding surfaces.Theoretical and experimental investigations have been carried out with the purpose to study changes in Q parameter according to the processed lens surface for various setting parameters of the technological equipment and their optimum values ensuring preferential stock removal in the central or boundary part zone or uniform distribution of the removal along the whole processed surface have been determined in the paper.The paper proposes a machine tool scheme for concurrent two-sided grinding and polishing of lenses while fixing their side (cylindrical surface. Machine tool kinematics makes it possible flexibly and within wide limits to change its setting parameters  that significantly facilitates the control of form-building process of parts with highly-precise spherical surfaces.Methodology for investigations presupposes the following: mathematical simulation of highly-precise spherical surface form-building process under conditions of forced closing, execution of numerical and experimental studies.  

  5. Human skin basement membrane-associated heparan sulphate proteoglycan: distinctive differences in ultrastructural localization as a function of developmental age

    DEFF Research Database (Denmark)

    Horiguchi, Y; Fine, J D; Couchman, J R

    1991-01-01

    was identical to that observed in neonatal and adult human skin. These findings demonstrate that active remodelling of the dermo-epidermal junction occurs during at least the first two trimesters, and affects not only basement membrane-associated structures but also specific antigens.......Recent studies have demonstrated that skin basement membrane components are expressed within the dermo-epidermal junction in an orderly sequence during human foetal development. We have investigated the ultrastructural localization of basement membrane-related antigens in human foetal skin...... at different developmental ages using two monoclonal antibodies to a well-characterized basement membrane-associated heparan sulphate proteoglycan. A series of foetal skin specimens (range, 54-142 gestational days) were examined using an immunoperoxidase immunoelectron microscopic technique. In specimens...

  6. Influence of CO2 on electrophysiology and ionic permeability of the basolateral membrane of frog skin

    International Nuclear Information System (INIS)

    Stoddard, J.S.

    1984-01-01

    When short-circuited epithelia of frog skin bathed in an alkaline Ringer solution equilibrated with room air, are exposed to a Ringer solution equilibrated with 5% CO 2 , inhibition of transepithelial Na + transport is observed accompanied by a marked depolarization of the basolateral membrane voltage as measured with intracellular microelectrodes. To study further the mechanisms involved, basolateral membrane influxes and effluxes of 24 Na, 42 K, and 36 Cl were measured in control and CO 2 -treated isolated epithelia. In control epithelia, studies of the bidirectional 24 Na fluxes confirmed the existence of an important basolateral membrane permeability to Na + . In control epithelia, the apical membranes of the cells were found to be virtually impermeable to Cl - , while basolateral membranes were highly permeable to Cl - . Although CO 2 caused a partial inhibition of pump activity as assessed from decreases of pump-mediated Na + efflux and K + influx, CO 2 caused little or no change of the leak influx of Na + or K + . K + efflux was increased markedly with CO 2 resulting in a net loss of K + from the cells. Cl - influx was increased and Cl - efflux was decreased by CO 2 leading to a net influx of Cl - . Analysis of the data according to criteria involving changes of flux, ionic equilibrium potentials, mass and charge balance restrictions indicated that the principle changes involve a transient decrease in electrical conductance to K + with a concurrent increase in electrical conductance to HCO 3 - (OH - or H + ) of the basolateral membranes of the cells

  7. A new method to determine the skin thickness of asymmetric UF-membranes using colloidal gold particles

    NARCIS (Netherlands)

    Cuperus, Folkert Petrus; Bargeman, Derk; Smolders, C.A.

    1990-01-01

    In this paper a new method is presented for the determination of the skin thickness of asymmetric ultrafiltration membranes. The method is based on the use of well-defined, uniformly sized colloidal gold particles, permeated from the sublayer side of the membrane, combined with electron microscopic

  8. The memory formalism in the diffusion of drugs through skin membrane

    Energy Technology Data Exchange (ETDEWEB)

    Caputo, Michele; Cametti, Cesare, E-mail: cesare.cametti@roma1.infn.i [Dipartimento di Fisica, Universita di Roma ' La Sapienza' , Piazzale A. Moro 2, I-00185 Rome (Italy) and CNR-INFM-SOFT, Unita di Roma1 Rome (Italy)

    2009-06-21

    The diffusion of drugs across a composite structure such as a biological membrane is a rather complex phenomenon, where the assumptions on which the Fick equations are based are not always true, because of the inhomogeneous nature of the lipid membrane, the diffusion rate and the solubility of the drug being strongly dependent on the local position across the membrane. These problems are particularly strengthened in composite structures of a considerable thickness such as the human skin, where the high heterogeneity provokes the transport through different simultaneous pathways. In this note, we generalize the diffusion model based on Fick's second equation by the introduction of a space-dependent diffusion constant within the memory formalism (diffusion with memory) approach. The model predictions have been compared with experimental results concerning the permeation of two different compounds through human skin in vivo, such as piroxicam, an anti-inflammatory drug and 4-cyanophenol, a test chemical model compound. In both cases, reasonably good agreement has been found.

  9. The memory formalism in the diffusion of drugs through skin membrane

    International Nuclear Information System (INIS)

    Caputo, Michele; Cametti, Cesare

    2009-01-01

    The diffusion of drugs across a composite structure such as a biological membrane is a rather complex phenomenon, where the assumptions on which the Fick equations are based are not always true, because of the inhomogeneous nature of the lipid membrane, the diffusion rate and the solubility of the drug being strongly dependent on the local position across the membrane. These problems are particularly strengthened in composite structures of a considerable thickness such as the human skin, where the high heterogeneity provokes the transport through different simultaneous pathways. In this note, we generalize the diffusion model based on Fick's second equation by the introduction of a space-dependent diffusion constant within the memory formalism (diffusion with memory) approach. The model predictions have been compared with experimental results concerning the permeation of two different compounds through human skin in vivo, such as piroxicam, an anti-inflammatory drug and 4-cyanophenol, a test chemical model compound. In both cases, reasonably good agreement has been found.

  10. [Lichen planus, a T-lymphocyte mediated reaction involving the skin and mucous membranes].

    Science.gov (United States)

    van den Akker, T W

    2001-10-06

    Lichen planus concerns a benign skin disorder without involvement of other organ systems. Its course is generally limited to less than a year. Classic lichen planus is characterized by pruritic, violaceous, plane papules which occur most commonly on the inside of the wrists, the lower back, the lower legs and the perimalleolar region of adults aged between 30-60 years. Frequently, oral and genital mucous membrane lesions are involved. Erosive mucosal lesions are particularly painful and long-lasting. Many clinical variants have been described ranging from lichenoid drug eruptions to associations with graft-versus-host disease. The cause of lichen planus is unknown. An immunopathological pathogenesis with T-lymphocytes directed against basal keratinocytes or the basal membrane zone is assumed. Multiple therapeutic options exist: local and systemic corticosteroids, psoralens with ultraviolet A light (PUVA), retinoids, cyclosporin.

  11. The human skin/chick chorioallantoic membrane model accurately predicts the potency of cosmetic allergens.

    Science.gov (United States)

    Slodownik, Dan; Grinberg, Igor; Spira, Ram M; Skornik, Yehuda; Goldstein, Ronald S

    2009-04-01

    The current standard method for predicting contact allergenicity is the murine local lymph node assay (LLNA). Public objection to the use of animals in testing of cosmetics makes the development of a system that does not use sentient animals highly desirable. The chorioallantoic membrane (CAM) of the chick egg has been extensively used for the growth of normal and transformed mammalian tissues. The CAM is not innervated, and embryos are sacrificed before the development of pain perception. The aim of this study was to determine whether the sensitization phase of contact dermatitis to known cosmetic allergens can be quantified using CAM-engrafted human skin and how these results compare with published EC3 data obtained with the LLNA. We studied six common molecules used in allergen testing and quantified migration of epidermal Langerhans cells (LC) as a measure of their allergic potency. All agents with known allergic potential induced statistically significant migration of LC. The data obtained correlated well with published data for these allergens generated using the LLNA test. The human-skin CAM model therefore has great potential as an inexpensive, non-radioactive, in vivo alternative to the LLNA, which does not require the use of sentient animals. In addition, this system has the advantage of testing the allergic response of human, rather than animal skin.

  12. Evaluation of Amniotic Membrane Effectiveness in Skin Graft Donor Site Dressing in Burn Patients.

    Science.gov (United States)

    Salehi, Seyed Hamid; As'adi, Kamran; Mousavi, Seyed Jaber; Shoar, Saeed

    2015-12-01

    Although the recipient site in burn wounds is dressed with universally accepted materials, the ideal management of split-thickness skin donor sites remains controversial. The aim of our study is to compare two methods of wound dressing in donor sites of split-thickness skin graft in patients undergoing burn wound reconstructive surgery. Forty-two consecutive patients with second- and third-degree burns with a total body surface area between 20 and 40 % were enrolled in this randomized clinical trial conducted in Motahari Burn Hospital in Tehran, Iran. In each patient, two anatomic areas with similar features were randomly selected as intervention and control donor sites. The intervention site was dressed with amniotic membrane, whereas the control site was treated with Vaseline-impregnated gauze. Wounds were examined daily by expert surgeons to measure the clinical outcomes including duration of healing, severity of pain, and infection rate. The mean ± SD age of patients was 31.17 ± 13.72 years; furthermore, burn percentage had a mean ± SD of 31.19 ± 10.56. The mean ± SD of patients' cooperation score was 1.6 ± 0.79 in the intervention group compared with 2.93 ± 0.71 in the control group, revealing a statistically significant difference (P  0.05). Amniotic membrane as an alternative for dressing of skin graft donor sites provides significant benefits by increasing patients' comfort via diminishing the number of dressing changes and facilitating the process of wound healing.

  13. Diabetes and Hepatitis C: Two sides of a coin

    Directory of Open Access Journals (Sweden)

    Muhammad Atif

    2017-05-01

    Full Text Available Background: Hepatitis C virus or HCV is a blood borne pathogen, transmitted primarily via blood, body secretions and by piercing through skin (percutaneous, veins and mucosal surfaces. Prevalence of HCV in Pakistan is 4.5-8%. The prevalence of HCV in diabetic patients is reported to be 14.9% in 2016. Different studies show different prevalence of Hepatitis C in local population of Pakistan. This study was designed to find out the prevalence of HCV in diabetic patients of different age groups and gender. Methods: Blood samples from 259 diabetic patients were collected at Diabetes Testing and Screening Camp arranged by Akhuwat Health Services (AHS at Township, Lahore. People of all age groups and gender were invited. Results were entered in MS Excel and analyzed on SPSS 19. Results: Out of 259 patients, 53% were females while 47% were males. This study shows the prevalence of HCV in Diabetic Patients as 8%. It was observed in diabetic patients, that females and patients from age group 30-40 years had high prevalence of HCV. Conclusion: The prevalence of Hepatitis C is high in the diabetic patients as compared to general population. HCV has a greater incidence in diabetic females of age group (30-40 years.

  14. Cytosolic lipolysis and lipophagy: two sides of the same coin.

    Science.gov (United States)

    Zechner, Rudolf; Madeo, Frank; Kratky, Dagmar

    2017-11-01

    Fatty acids are the most efficient substrates for energy production in vertebrates and are essential components of the lipids that form biological membranes. Synthesis of triacylglycerols from non-esterified free fatty acids (FFAs) combined with triacylglycerol storage represents a highly efficient strategy to stockpile FFAs in cells and prevent FFA-induced lipotoxicity. Although essentially all vertebrate cells have some capacity to store and utilize triacylglycerols, white adipose tissue is by far the largest triacylglycerol depot and is uniquely able to supply FFAs to other tissues. The release of FFAs from triacylglycerols requires their enzymatic hydrolysis by a process called lipolysis. Recent discoveries thoroughly altered and extended our understanding of lipolysis. This Review discusses how cytosolic 'neutral' lipolysis and lipophagy, which utilizes 'acid' lipolysis in lysosomes, degrade cellular triacylglycerols as well as how these pathways communicate, how they affect lipid metabolism and energy homeostasis and how their dysfunction affects the pathogenesis of metabolic diseases. Answers to these questions will likely uncover novel strategies for the treatment of prevalent metabolic diseases.

  15. Study of sunless tanning formulas using molted snake skin as an alternative membrane model.

    Science.gov (United States)

    Balogh, T S; Pedriali, C A; Gama, R M; de Oliveira Pinto, C A S; Bedin, V; Villa, R T; Kaneko, T M; Consiglieri, V O; Velasco, M V R; Baby, A R

    2011-08-01

    Sunless tanning formulas have become increasingly popular in recent years for their ability to give people convincing tans without the dangers of skin cancer. Most sunless tanners currently on the market contain dihydroxyacetone (DHA), a keto sugar with three carbons. The temporary pigment provided by these formulas is designed to resemble a UV-induced tan. This study evaluated the effectiveness of carbomer gels and cold process self emulsifying bases on skin pigmentation, using different concentrations of a chemical system composed of DHA and N-acetyl tyrosine, which are found in moulted snake skins and their effectiveness was tested by Mexameter(®) MX 18. Eight different sunless tanning formulas were developed, four of which were gels and four of which were emulsions (base, base plus 4.0%, 5.0% and 6.0% (w/w) of a system of DHA and N-acetyl tyrosine). Tests to determine the extent of artificial tanning were done by applying 30 mg cm(-2) of each formula onto standard sizes of moulted snake skin (2.0 cm × 3.0 cm). A Mexameter(®) MX 18 was used to evaluate the extent of coloration in the moulted snake skin at T(0) (before the application) and after 24, 48, 72, 168, 192 and 216 h. The moulted snake skins can be used as an alternative membrane model for in vitro sunless tanning efficacy tests due to their similarity to the human stratum corneum. The DHA concentration was found to influence the initiation of the pigmentation in both sunless tanning systems (emulsion and gel) as well as the time required to increases by a given amount on the tanning index. In the emulsion system, the DHA concentration also influenced the final value on the tanning index. The type of system (emulsion or gel) has no influence on the final value in the tanning index after 216 h for samples with the same DHA concentration. © 2011 The Authors. ICS © 2011 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  16. Physiochemical properties and resorption progress of porcine skin-derived collagen membranes: In vitro and in vivo analysis.

    Science.gov (United States)

    An, Yin-Zhe; Kim, You-Kyoung; Lim, Su-Min; Heo, Yeong-Ku; Kwon, Mi-Kyung; Cha, Jae-Kook; Lee, Jung-Seok; Jung, Ui-Won; Choi, Seong-Ho

    2018-03-30

    The aim of the present study was to evaluate the physiochemical properties and resorption progress of two cross-linked, porcine skin-derived collagen membranes and compare their features with those of a membrane without cross-linking (Bio-Gide ® [BG], Geistlich Biomaterials, Wolhusen, Switzerland). Three porcine skin-derived collagen membranes, dehydrothermally (DHT) cross-linked (experimental), DHT and 1-ethyl-3(3-dimethylaminopropyl)-carbodiimide (DHT/EDC) cross-linked (experimental) and BG were investigated for their morphology, enzyme resistance, and tensile strength in vitro and biodegradation in vivo. DHT and DHT/EDC membranes exhibited irregular, interconnected macro- and micropores that formed a 3D mesh, whereas BG exhibited individual collagen fibrils interlaced to form coarse collagen strands. In enzyme resistance and tensile strength tests, DHT and DHT/EDC membranes demonstrated good resistance and mechanical properties compared with BG. In vivo, all three membranes were well integrated into the surrounding connective tissue. Thus, the DHT membrane exhibited its potential as a barrier membrane for guided bone and tissue regeneration.

  17. DMPD: Targeting bacterial endotoxin: two sides of a coin. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available n M. Ann N Y Acad Sci. 2007 Jan;1096:1-17. (.png) (.svg) (.html) (.csml) Show Targeting bacterial endotoxin: two sides of a coin. Pub...medID 17405910 Title Targeting bacterial endotoxin: two sides of a coin. Authors Bo

  18. Price Competition in Two-Sided Markets with Heterogeneous Consumers and Network Effects

    NARCIS (Netherlands)

    Filistrucchi, L.; Klein, T.J.

    We model a two-sided market with heterogeneous customers and two heterogeneous network effects. In our model, customers on each market side care differently about both the number and the type of customers on the other side. Examples of two-sided markets are online platforms or daily newspapers. In

  19. Krylov-Schur-Type restarts for the two-sided arnoldi method

    NARCIS (Netherlands)

    Zwaan, I.N.; Hochstenbach, M.E.

    2017-01-01

    We consider the two-sided Arnoldi method and propose a two-sided Krylov-Schurtype restarting method. We discuss the restart for standard Rayleigh-Ritz extraction as well as harmonic Rayleigh-Ritz extraction. Additionally, we provide error bounds for Ritz values and Ritz vectors in the context of

  20. In vivo performance of chitosan/soy-based membranes as wound-dressing devices for acute skin wounds.

    Science.gov (United States)

    Santos, Tírcia C; Höring, Bernhard; Reise, Kathrin; Marques, Alexandra P; Silva, Simone S; Oliveira, Joaquim M; Mano, João F; Castro, António G; Reis, Rui L; van Griensven, Martijn

    2013-04-01

    Wound management represents a major clinical challenge on what concerns healing enhancement and pain control. The selection of an appropriate dressing plays an important role in both recovery and esthetic appearance of the regenerated tissue. Despite the wide range of available dressings, the progress in the wound care market relies on the increasing interest in using natural-based biomedical products. Herein, a rat wound-dressing model of partial-thickness skin wounds was used to study newly developed chitosan/soy (cht/soy)-based membranes as wound-dressing materials. Healing and repair of nondressed, cht/soy membrane-dressed, and Epigard(®)-dressed wounds were followed macroscopically and histologically for 1 and 2 weeks. cht/soy membranes performed better than the controls, promoting a faster wound repair. Re-epithelialization, observed 1 week after wounding, was followed by cornification of the outermost epidermal layer at the second week of dressing, indicating repair of the wounded tissue. The use of this rodent model, although in impaired healing conditions, may enclose some drawbacks regarding the inevitable wound contraction. Moreover, being the main purpose the evaluation of cht/soy-based membranes' performance in the absence of growth factors, the choice of a clinically relevant positive control was limited to a polymeric mesh, without any growth factor influencing skin healing/repair, Epigard. These new cht/soy membranes possess the desired features regarding healing/repair stimulation, ease of handling, and final esthetic appearance-thus, valuable properties for wound dressings.

  1. Comparative evaluation of rivastigmine permeation from a transdermal system in the Franz cell using synthetic membranes and pig ear skin with in vivo-in vitro correlation.

    Science.gov (United States)

    Simon, Alice; Amaro, Maria Inês; Healy, Anne Marie; Cabral, Lucio Mendes; de Sousa, Valeria Pereira

    2016-10-15

    In the present study, in vitro permeation experiments in a Franz diffusion cell were performed using different synthetic polymeric membranes and pig ear skin to evaluate a rivastigmine (RV) transdermal drug delivery system. In vitro-in vivo correlations (IVIVC) were examined to determine the best model membrane. In vitro permeation studies across different synthetic membranes and skin were performed for the Exelon(®) Patch (which contains RV), and the results were compared. Deconvolution of bioavailability data using the Wagner-Nelson method enabled the fraction of RV absorbed to be determined and a point-to-point IVIVC to be established. The synthetic membrane, Strat-M™, showed a RV permeation profile similar to that obtained with pig ear skin (R(2)=0.920). Studies with Strat-M™ resulted in a good and linear IVIVC (R(2)=0.991) when compared with other synthetic membranes that showed R(2) values less than 0.90. The R(2) for pig ear skin was 0.982. Strat-M™ membrane was the only synthetic membrane that adequately simulated skin barrier performance and therefore it can be considered to be a suitable alternative to human or animal skin in evaluating transdermal drug transport, potentially reducing the number of studies requiring human or animal samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. The advertising-financed business model in two-sided media markets

    OpenAIRE

    Anderson, Simon P.; Jullien, Bruno

    2016-01-01

    This chapter focuses on the economic mechanisms at work in recent models of advertising finance in media markets developed around the concept of two-sided markets. The objective is to highlight new and original insights from this approach, and to clarify the conceptual aspects. The chapter first develops a canonical model of two-sided markets for advertising, where platforms deliver content to consumers and resell their "attention" to advertisers. A key distinction is drawn between free media...

  3. Promotion of cooperation induced by two-sided players in prisoner's dilemma game

    Science.gov (United States)

    Su, Zhen; Li, Lixiang; Xiao, Jinghua; Podobnik, B.; Stanley, H. Eugene

    2018-01-01

    We examine how real-world individuals and companies can either reach an agreement or fail to reach an agreement after several stages of negotiation. We use a modified prisoner's dilemma game with two-sided players who can either cooperate or not cooperate with their neighbors. We find that the presence of even a small number of these two-sided players substantially promotes the cooperation because, unlike the rock-paper-scissors scenario, when the cooperators change to the non-cooperators to gain a payoff, they can turn to the two-sided players and continue negotiating. We find that the network structure influences the spread of strategies. Lattice and regular-random (RR) networks benefit the spread of both non-cooperation and two-sided strategies, but scale-free (SF) networks stop both strategies. We also find that the Erdös-R e ´ nyi (ER) network promotes the two-sided strategy and blocks the spread of non-cooperation. As the ER network density decreases, and the network degree is lowered the lifetime of non-cooperators increases. Our results expand our understanding of the role played by the two-sided strategy in the growth of the cooperative behavior in networks.

  4. Skin

    International Nuclear Information System (INIS)

    Hunter, R.D.

    1985-01-01

    Malignant disease involving the skin represents a significant work load to the general radiotherapist and can involve interesting diagnostic and therapeutic decisions. Primary skin cancer is also relatively common and there is a need to provide an efficient service in which the first treatment is successful in the majority of patients. The reward for careful attention to technique is very considerable both in terms of clinical cancer control and functional results. Squamous cell carcinoma, basal cell carcinoma, and intra-epidermal carcinoma constitute the majority of the lesions dealt with clinically, but metastatic disease, lymphomas, and malignant melanomas are also referred regularly for opinions and may require radiotherapy. The general principle of the techniques of assessment and radiotherapeutic management to be described are equally applicable to any malignant skin tumour once the decision has been made to accept it for radiotherapy. Dosage and fractionation may have to be adjusted to allow for the nature of the disease process and the intent of the treatment

  5. The skin migratory stage of the schistosomulum of Schistosoma mansoni has a surface showing greater permeability and activity in membrane internalisation than other forms of skin or mechanical schistosomula.

    Science.gov (United States)

    DE Jesus Jeremias, Wander; DA Cunha Melo, Jose Renan; Baba, Elio Hideo; Coelho, Paulo Marcos Zech; Kusel, John Robert

    2015-08-01

    Skin schistosomula can be prepared by collecting them after isolated mouse skin have been penetrated by cercariae in vitro. The schistosomula can also migrate out of isolated mouse skin penetrated by cercariae in vitro and from mouse skin penetrated by cercariae in vivo. Schistosomula can also be produced from cercariae applied through a syringe or in a vortex. When certain surface properties of the different forms of schistosomula were compared, those migrating from mouse skin penetrated by cercariae in vivo or in vitro had greatly increased permeability to membrane impermeant molecules such as Lucifer yellow and high molecular weight dextrans. These migrating forms also possessed surfaces which showed greatly enhanced uptake into internal membrane vesicles of the dye FM 143, a marker for endocytosis. This greatly enhanced activity and permeability of the surfaces of tissue migrating schistosomula is likely to be of great importance in the adaptation to the new host.

  6. Successive Two-sided Loop Jets Caused by Magnetic Reconnection between Two Adjacent Filamentary Threads

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Zhanjun; Liu, Yu; Shen, Yuandeng [Yunnan Observatories, Chinese Academy of Sciences, Kunming, 650216 (China); Elmhamdi, Abouazza; Kordi, Ayman S. [Department of Physics and Astronomy, King Saud University, P.O. Box 2455, 11451 (Saudi Arabia); Su, Jiangtao [University of Chinese Academy of Sciences, Beijing 100049 (China); Liu, Ying D., E-mail: ydshen@ynao.ac.cn [State Key Laboratory of Space Weather, Chinese Academy of Sciences, Beijing 100190 (China)

    2017-08-20

    We present observational analysis of two successive two-sided loop jets observed by the ground-based New Vacuum Solar Telescope and the space-borne Solar Dynamics Observatory . The two successive two-sided loop jets manifested similar evolution processes and both were associated with the interaction of two small-scale adjacent filamentary threads, magnetic emerging, and cancellation processes at the jet’s source region. High temporal and high spatial resolution observations reveal that the two adjacent ends of the two filamentary threads are rooted in opposite magnetic polarities within the source region. The two threads approached each other, and then an obvious brightening patch is observed at the interaction position. Subsequently, a pair of hot plasma ejections are observed heading in opposite directions along the paths of the two filamentary threads at a typical speed for two-sided loop jets of the order 150 km s{sup −1}. Close to the end of the second jet, we report the formation of a bright hot loop structure at the source region, which suggests the formation of new loops during the interaction. Based on the observational results, we propose that the observed two-sided loop jets are caused by magnetic reconnection between the two adjacent filamentary threads, largely different from the previous scenario that a two-sided loop jet is generated by magnetic reconnection between an emerging bipole and the overlying horizontal magnetic fields.

  7. Specific binding of prostaglandin E2 to membrane preparations from human skin: receptor modulation by UVB-irradiation and chemical agents

    International Nuclear Information System (INIS)

    Lord, J.T.; Ziboh, V.A.

    1979-01-01

    Human skin membranes bind prostaglandin E2 (PGE2) with high affinity and specificity. This binding is inhibited by trypsin or heat treatment suggesting that PGE2 receptors have protein components. Exposure of the membranes to ultraviolet irradiation (UVB) resulted in the loss of the membrane binding capacity for PGE2. This UVB-inhibitory effect could be prevented by a known protein sulfhydryl-oxidizing agent and a known lipid anti-oxidant

  8. Evaluation of the Membrane Permeability (PAMPA and Skin) of Benzimidazoles with Potential Cannabinoid Activity and their Relation with the Biopharmaceutics Classification System (BCS)

    OpenAIRE

    Alvarez-Figueroa, M. Javiera; Pessoa-Mahana, C. David; Palavecino-González, M. Elisa; Mella-Raipán, Jaime; Espinosa-Bustos, Cristián; Lagos-Muñoz, Manuel E.

    2011-01-01

    The permeability of five benzimidazole derivates with potential cannabinoid activity was determined in two models of membranes, parallel artificial membrane permeability assay (PAMPA) and skin, in order to study the relationship of the physicochemical properties of the molecules and characteristics of the membranes with the permeability defined by the Biopharmaceutics Classification System. It was established that the PAMPA intestinal absorption method is a good predictor for classifying thes...

  9. The plasma membrane-associated NADH oxidase (ECTO-NOX) of mouse skin responds to blue light

    Science.gov (United States)

    Morre, D. James; Morre, Dorothy M.

    2003-01-01

    NADH oxidases of the external plasma membrane surface (ECTO-NOX proteins) are characterized by oscillations in activity with a regular period length of 24 min. Explants of mouse skin exhibit the oscillatory activity as estimated from the decrease in A(340) suggesting that individual ECTO-NOX molecules must somehow be induced to function synchronously. Transfer of explants of mouse skin from darkness to blue light (495 nm, 2 min, 50 micromol m(-1) s(-1)) resulted in initiation of a new activity maximum (entrainment) with a midpoint 36 min after light exposure followed by maxima every 24 min thereafter. Addition of melatonin resulted in a new maximum 24 min after melatonin addition. The findings suggest that the ECTO-NOX proteins play a central role in the entrainment of the biological clock both by light and by melatonin.

  10. On revenue and welfare dominance of ad valorem taxes in two-sided markets

    DEFF Research Database (Denmark)

    Kind, Hans Jarle; Köthenbürger, Marko; Schjelderup, Guttorm

    2009-01-01

    A benchmark result in public economics is that it is possible to increase both tax revenue and welfare by making a monopoly subject to ad valorem taxes rather than unit taxes. We show that such revenue and welfare dominance does not hold in two-sided markets.......A benchmark result in public economics is that it is possible to increase both tax revenue and welfare by making a monopoly subject to ad valorem taxes rather than unit taxes. We show that such revenue and welfare dominance does not hold in two-sided markets....

  11. Direct visualization of lipid domains in human skin stratum corneum's lipid membranes

    DEFF Research Database (Denmark)

    Plasencia, I; Norlen, Lars; Bagatolli, Luis

    2007-01-01

    scanning calorimetry, fluorescence spectroscopy, and two-photon excitation and laser scanning confocal fluorescence microscopy. Here we show that hydrated bilayers of human skin stratum corneum lipids express a giant sponge-like morphology with dimensions corresponding to the global three......-dimensional morphology of the stratum corneum extracellular space. These structures can be directly visualized using the aforementioned fluorescence microscopy techniques. At skin physiological temperatures (28 degrees C-32 degrees C), the phase state of these hydrated bilayers correspond microscopically (radial...

  12. Computer program determines exact two-sided tolerance limits for normal distributions

    Science.gov (United States)

    Friedman, H. A.; Webb, S. R.

    1968-01-01

    Computer program determines by numerical integration the exact statistical two-sided tolerance limits, when the proportion between the limits is at least a specified number. The program is limited to situations in which the underlying probability distribution for the population sampled is the normal distribution with unknown mean and variance.

  13. Regenerative and Antibacterial Properties of Acellular Fish Skin Grafts and Human Amnion/Chorion Membrane: Implications for Tissue Preservation in Combat Casualty Care.

    Science.gov (United States)

    Magnusson, Skuli; Baldursson, Baldur Tumi; Kjartansson, Hilmar; Rolfsson, Ottar; Sigurjonsson, Gudmundur Fertram

    2017-03-01

    Improvised explosive devices and new directed energy weapons are changing warfare injuries from penetrating wounds to large surface area thermal and blast injuries. Acellular fish skin is used for tissue repair and during manufacturing subjected to gentle processing compared to biologic materials derived from mammals. This is due to the absence of viral and prion disease transmission risk, preserving natural structure and composition of the fish skin graft. The aim of this study was to assess properties of acellular fish skin relevant for severe battlefield injuries and to compare those properties with those of dehydrated human amnion/chorion membrane. We evaluated cell ingrowth capabilities of the biological materials with microscopy techniques. Bacterial barrier properties were tested with a 2-chamber model. The microstructure of the acellular fish skin is highly porous, whereas the microstructure of dehydrated human amnion/chorion membrane is mostly nonporous. The fish skin grafts show superior ability to support 3-dimensional ingrowth of cells compared to dehydrated human amnion/chorion membrane (p fish skin is a bacterial barrier for 24 to 48 hours. The unique biomechanical properties of the acellular fish skin graft make it ideal to be used as a conformal cover for severe trauma and burn wounds in the battlefield. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

  14. Study of skin and mucous membrane disorders among workers engaged in the sodium dichromate manufacturing industry and chrome plating industry.

    Science.gov (United States)

    Singhal, Vijay Kumar; Deswal, Balbir Singh; Singh, Bachu Narayan

    2015-01-01

    Inhalation of dusts and fumes arising during the manufacture of sodium dichromate from chrome ore, chromic acid mist emitted during electroplating, and skin contact with chromate produce hazards to workers. (1) To elucidate the prevalence of skin and mucous membrane disorders among the workers engaged in the sodium dichromate manufacturing industry and chrome plating industry. (2) To know the relationship of prevalence with the duration of exposure to chrome mist, dust, and fumes. A cross-sectional study was conducted among all the workers engaged in sodium dichromate manufacturing and chrome plating from several industries situated near the Delhi-Haryana border in the districts of Faridabad and Sonepat of Haryana, India from January 01, 2014 to December 31, 2014. All the workers available from the concerned industries for the study were interviewed and medically examined after obtaining their informed consent. A total of 130 workers comprising 66 workers from the sodium dichromate manufacturing industry and 64 workers from the chrome plating industry were examined on a pretested schedule. Descriptive statistical methods (proportions, relative risk, and Chi-square test of significance with P value analyzed using Epi Info version 7). All the workers were found to be males and of the adult age group. Out of the total examined, 69.69% and 56.22% of the workers had disorders of the nasal mucous membrane in the sodium dichromate manufacturing industry and the chrome plating industry, respectively. 42.42% and 28.22% of the workers had perforation of the nasal septum in the sodium dichromate manufacturing industry and chrome plating industry, respectively. 6.06% and 3.12% workers had skin ulcers in the sodium dichromate manufacturing industry and chrome plating industry, respectively. Nasal irritation and rhinorrhea were the most commonly found symptoms in both the processes. 48.48% and 90.52% of the workers were using hand gloves in the sodium dichromate manufacturing

  15. Dual-skinned polyamide/poly(vinylidene fluoride)/cellulose acetate membranes with embedded woven

    KAUST Repository

    Duong, Phuoc H.H.

    2016-08-31

    We propose multilayer membranes including (i) a thin selective polyamide (PA) layer prepared via interfacial polymerization, (ii) a poly (vinylidene fluoride) (PVDF) asymmetric porous support with high adhesion to the PA layer and high mechanical strength, (iii) a strong woven fabric, and (iv) fouling resistant porous cellulose acetate (CA) layer. The PA layer rejects solutes of the draw solution. The PVDF/woven fabric/CA (PVDF/CA) integrated layer performs as a mechanical support with unique properties for forward osmosis (FO) applications. It consists of a modified PVDF top layer suitable for the deposition of a PA layer and a highly hydrophilic bottom layer (CA) with a tunable pore size to minimize foulant deposition and intrusion onto and into the support. The experimental results using bovine serum albumin (BSA) as a model foulant show that the presence of the CA layer at the bottom of the FO membrane (PA/PVDF/CA) reduces 75% fouling propensity compared to the simple FO membrane made of PVDF, woven fabric and PA (PA/PVDF). Fouling tests with 2000 ppm oily feed faced the bottom of the FO membranes further indicate the superiority of the PA/PVDF/CA membrane compared to the PA/PVDF membrane. Moreover, the bottom CA layer can be adjusted with a flexible range of pore size, varied from sub-micron to sub-nanometer depending on the feed composition. The newly developed multilayer FO membrane has comparable performance to the state-of-the-art membrane with added tailored fouling resistance for specific wastewater feeds.

  16. Skin secretion of Siphonops paulensis (Gymnophiona, Amphibia forms voltage-dependent ionic channels in lipid membranes

    Directory of Open Access Journals (Sweden)

    E.F. Schwartz

    2003-09-01

    Full Text Available The effect of the skin secretion of the amphibian Siphonops paulensis was investigated by monitoring the changes in conductance of an artificial planar lipid bilayer. Skin secretion was obtained by exposure of the animals to ether-saturated air, and then rinsing the animals with distilled water. Artificial lipid bilayers were obtained by spreading a solution of azolectin over an aperture of a Delrin cup inserted into a cut-away polyvinyl chloride block. In 9 of 12 experiments, the addition of the skin secretion to lipid bilayers displayed voltage-dependent channels with average unitary conductance of 258 ± 41.67 pS, rather than nonspecific changes in bilayer conductance. These channels were not sensitive to 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid or tetraethylammonium ion, but the experimental protocol used does not permit us to specify their characteristics.

  17. Protein nanocoatings on synthetic polymeric nanofibrous membranes designed as carriers for skin cells

    Czech Academy of Sciences Publication Activity Database

    Bačáková, Markéta; Pajorová, Julie; Stránská, D.; Hadraba, Daniel; Lopot, F.; Riedel, Tomáš; Brynda, Eduard; Žaloudková, Margit; Bačáková, Lucie

    2017-01-01

    Roč. 12, Feb (2017), s. 1143-1160 E-ISSN 1178-2013 R&D Projects: GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:67985823 ; RVO:67985891 ; RVO:61389013 Keywords : skin-tissue engineering * nanocoating * nanofibers * skin cells * fibrin * collagen Subject RIV: EI - Biotechnology ; Bionics; EI - Biotechnology ; Bionics (UMCH-V); EI - Biotechnology ; Bionics (USMH-B) OBOR OECD: Technologies involving the manipulation of cells, tissues, organs or the whole organism (assisted reproduction); Biomaterials (as related to medical implants, devices, sensors) (UMCH-V); Health-related biotechnology (USMH-B) Impact factor: 4.300, year: 2016

  18. Evaluation of Human Amniotic Membrane as a Wound Dressing for Split-Thickness Skin-Graft Donor Sites

    Directory of Open Access Journals (Sweden)

    Denys J. Loeffelbein

    2014-01-01

    Full Text Available Human amniotic membrane (HAM has been used as a biomaterial in various surgical procedures and exceeds some qualities of common materials. We evaluated HAM as wound dressing for split-thickness skin-graft (STSG donor sites in a swine model (Part A and a clinical trial (Part B. Part A: STSG donor sites in 4 piglets were treated with HAM or a clinically used conventional polyurethane (PU foil (n=8 each. Biopsies were taken on days 5, 7, 10, 20, 40, and 60 and investigated immunohistochemically for alpha-smooth muscle actin (αSMA: wound contraction marker, von Willebrand factor (vWF: angiogenesis, Ki-67 (cell proliferation, and laminin (basement membrane integrity. Part B: STSG donor sites in 45 adult patients (16 female/29 male were treated with HAM covered by PU foam, solely by PU foam, or PU foil/paraffin gauze (n=15 each. Part A revealed no difference in the rate of wound closure between groups. HAM showed improved esthetic results and inhibitory effects on cicatrization. Angioneogenesis was reduced, and basement membrane formation was accelerated in HAM group. Part B: no difference in re-epithelialization/infection rate was found. HAM caused less ichor exudation and less pruritus. HAM has no relevant advantage over conventional dressings but might be a cost-effective alternative.

  19. A Two-Sided Market Model of Optimal Price Structure for Instant Messenger

    Directory of Open Access Journals (Sweden)

    Jun Xu

    2013-01-01

    Full Text Available Instant messenger (IM is one of the most popular Internet applications all over the world. This paper examines the pricing problem of IM based on two-sided market model. IM serves as a two-sided platform, which gets both Internet users and advertisers on board. This paper concludes that IM operator adopts a heavily skewed price structure that favors IM users both under monopolistic case and under horizontal differentiated duopolistic case. When advertising revenue is large enough relatively to marginal cost for serving IM users, IM users can enjoy free service provided by IM operators. The competitive equilibrium of duopolistic case is not necessarily symmetric when advertisers choose singlehoming. Even in the symmetric equilibrium platform would rather deter all advertisers.

  20. Interpretation of the measurement of ions fluxes through a biological membrane with a cellular compartment: example of the movements of sodium through the skin of frogs

    International Nuclear Information System (INIS)

    Morel, F.

    1959-01-01

    Two-way ion fluxes which can be measured in vitro through a living epithelial membrane (such as frog skin) by the indicator method take place across the cells which behave like an intermediate ionic 'compartment'. Two membranes and four fluxes have thus to be considered. Measurements in vitro of the total sodium fluxes as a function of the sodium concentration in the medium in contact with the external face of the skin have been interpreted in this spirit. Making use of certain hypotheses, the permeability coefficients for sodium of the two cellular membranes, the four sodium fluxes, the intracellular sodium concentration and the membrane potentials have been calculated for each value of the sodium concentration in the external medium. (author) [fr

  1. Bargaining with Incomplete Information: An Infinite-Horizon Model with Two-Sided Uncertainty

    OpenAIRE

    Peter Cramton

    1984-01-01

    The resolution of any bargaining conflict depends crucially on the relative urgency of the agents to reach agreement and the information each agent has about the others' preferences. This paper explores, within the context of an infinite-horizon bargaining model with two-sided uncertainty, how timing and information affect the rational behaviour of agents when commitment is not possible. Since the bargainers are uncertain about whether trade is desirable, they must communicate some of their p...

  2. Persistence Probabilities of Two-Sided (Integrated) Sums of Correlated Stationary Gaussian Sequences

    Science.gov (United States)

    Aurzada, Frank; Buck, Micha

    2018-02-01

    We study the persistence probability for some two-sided, discrete-time Gaussian sequences that are discrete-time analogues of fractional Brownian motion and integrated fractional Brownian motion, respectively. Our results extend the corresponding ones in continuous time in Molchan (Commun Math Phys 205(1):97-111, 1999) and Molchan (J Stat Phys 167(6):1546-1554, 2017) to a wide class of discrete-time processes.

  3. Application of Two-Sided Matching to Internal Labor of the Hellenic Navy

    Science.gov (United States)

    2012-03-01

    Figure 7. The NIMP Algorithm¹³ The first memorable theoretical study of two-sided matching belongs to Milton Friedman and his 1955 article, “The Role...Military Personnel” (Master’s thesis, Naval Postgraduate School, Monterey, 2011). 15. Milton Friedman . “The Role of Government in Education,” in...Research, Cambridge, Massachusetts, June, 2009. Friedman , Milton . “The Role of Government in Education.” In Economics and the Public Interest, edited

  4. Electromotive force and impedance studies of cellulose acetate membranes: Evidence for two binding sites for divalent cations and for an alveolar structure of the skin layer

    DEFF Research Database (Denmark)

    Smith Sørensen, T.; Jensen, J.B.; Malmgren-Hansen, B.

    1991-01-01

    asymmetic membranes. The skin layer in asymmetric membranes is assumed to have properties similar to dense membranes. The EMF measurements were interpreted by means of a Donnan-Nernst-Planck (Teorell-Meyer-Sievers) model, which functions quite well due to the low fixed charge in the membrane. The membrane...... diffusion potential is calculated by the Henderson method and in some cases by solving transcendental equations according to Planck, Pleijel and Schlogl. There is no great difference between the membrane potentials calculated by the two methods, but the ion profiles and the actual rates of electrodiffusion...... of ca. 30 in the alveolar phase is also supported by a simple dielectric calculation of the Nernst distribution of mono- and divalent ions between external water and the alveolar solution. Corrections for activity coefficients only seems important above 0.5 M. The Onsager-Samaras dielectric repulsion...

  5. Scheduling Two-Sided Transformations Using Tile Algorithms on Multicore Architectures

    Directory of Open Access Journals (Sweden)

    Hatem Ltaief

    2010-01-01

    Full Text Available The objective of this paper is to describe, in the context of multicore architectures, three different scheduler implementations for the two-sided linear algebra transformations, in particular the Hessenberg and Bidiagonal reductions which are the first steps for the standard eigenvalue problems and the singular value decompositions respectively. State-of-the-art dense linear algebra softwares, such as the LAPACK and ScaLAPACK libraries, suffer performance losses on multicore processors due to their inability to fully exploit thread-level parallelism. At the same time the fine-grain dataflow model gains popularity as a paradigm for programming multicore architectures. Buttari et al. (Parellel Comput. Syst. Appl. 35 (2009, 38–53 introduced the concept of tile algorithms in which parallelism is no longer hidden inside Basic Linear Algebra Subprograms but is brought to the fore to yield much better performance. Along with efficient scheduling mechanisms for data-driven execution, these tile two-sided reductions achieve high performance computing by reaching up to 75% of the DGEMM peak on a 12000×12000 matrix with 16 Intel Tigerton 2.4 GHz processors. The main drawback of the tile algorithms approach for two-sided transformations is that the full reduction cannot be obtained in one stage. Other methods have to be considered to further reduce the band matrices to the required forms.

  6. The use dibunol therapy for radiation injuries of the skin and mucous membranes

    International Nuclear Information System (INIS)

    Agafonova, G.B.; Barsel', V.A.; Sarkisyan, Yu.Kh.; Terekhova, G.S.; Podlyashchuk, E.L.; Ustinova, V.F.; AN SSSR, Moscow. Inst. Khimicheskoj Fiziki)

    1983-01-01

    There are presented the results of the use of dibunol in the form of liniment (1-10%) for the treatment of radiation cystitis and rectitis resulting from radiation therapy of small pelvic tumors, epidermitis and epithelitis that develop in the course of treatment of skin and lower lip tumors. A high efficacy of the drug in the therapy of radiation injury has been shown in 212 patients

  7. Use dibunol therapy for radiation injuries of the skin and mucous membranes

    Energy Technology Data Exchange (ETDEWEB)

    Agafonova, G.B.; Barsel' , V.A.; Sarkisyan, Yu.Kh.; Terekhova, G.S.; Podlyashchuk, E.L.; Ustinova, V.F. (Nauchno-Issledovatel' skij Inst. Rentgenologii i Radiologii, Moscow (USSR); AN SSSR, Moscow. Inst. Khimicheskoj Fiziki)

    1983-04-01

    There are presented the results of the use of dibunol in the form of liniment (1-10%) for the treatment of radiation cystitis and rectitis resulting from radiation therapy of small pelvic tumors, epidermitis and epithelitis that develop in the course of treatment of skin and lower lip tumors. A high efficacy of the drug in the therapy of radiation injury has been shown in 212 patients.

  8. From membrane to skin: aqueous permeation control through light-responsive amphiphilic polymer co-networks

    Czech Academy of Sciences Publication Activity Database

    Schöller, K.; Küpfer, S.; Baumann, L.; Hoyer, P.M.; de Courten, D.; Rossi, R.M.; Vetushka, Aliaksi; Wolf, M.; Bruns, N.; Scherer, L.J.

    2014-01-01

    Roč. 24, č. 33 (2014), s. 5194-5201 ISSN 1616-301X R&D Projects: GA ČR GB14-37427G; GA MŠk(CZ) LM2011026 Institutional support: RVO:68378271 Keywords : transdermal drug-delivery * porcine ear skin * in-vitro * surface modification Subject RIV: JI - Composite Materials Impact factor: 11.805, year: 2014

  9. Hair Follicle Morphogenesis in the Treatment of Mouse Full-Thickness Skin Defects Using Composite Human Acellular Amniotic Membrane and Adipose Derived Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Wu Minjuan

    2016-01-01

    Full Text Available Early repair of skin injury and maximal restoration of the function and appearance have become important targets of clinical treatment. In the present study, we observed the healing process of skin defects in nude mice and structural characteristics of the new skin after transplantation of isolated and cultured adipose derived mesenchymal stem cells (ADMSCs onto the human acellular amniotic membrane (AAM. The result showed that ADMSCs were closely attached to the surface of AAM and grew well 24 h after seeding. Comparison of the wound healing rate at days 7, 14, and 28 after transplantation showed that ADMSCs seeded on AAM facilitated the healing of full-thickness skin wounds more effectively as compared with either hAM or AAM alone, indicating that ADMSCs participated in skin regeneration. More importantly, we noticed a phenomenon of hair follicle development during the process of skin repair. Composite ADMSCs and AAM not only promoted the healing of the mouse full-thickness defects but also facilitated generation of the appendages of the affected skin, thus promoting restoration of the skin function. Our results provide a new possible therapy idea for the treatment of skin wounds with respect to both anatomical regeneration and functional restoration.

  10. Skin Basement Membrane: The Foundation of Epidermal Integrity—BM Functions and Diverse Roles of Bridging Molecules Nidogen and Perlecan

    Directory of Open Access Journals (Sweden)

    Dirk Breitkreutz

    2013-01-01

    Full Text Available The epidermis functions in skin as first defense line or barrier against environmental impacts, resting on extracellular matrix (ECM of the dermis underneath. Both compartments are connected by the basement membrane (BM, composed of a set of distinct glycoproteins and proteoglycans. Herein we are reviewing molecular aspects of BM structure, composition, and function regarding not only (i the dermoepidermal interface but also (ii the resident microvasculature, primarily focusing on the per se nonscaffold forming components perlecan and nidogen-1 and nidogen-2. Depletion or functional deficiencies of any BM component are lethal at some stage of development or around birth, though BM defects vary between organs and tissues. Lethality problems were overcome by developmental stage- and skin-specific gene targeting or by cell grafting and organotypic (3D cocultures of normal or defective cells, which allows recapitulating BM formation de novo. Thus, evidence is accumulating that BM assembly and turnover rely on mechanical properties and composition of the adjacent ECM and the dynamics of molecular assembly, including further “minor” local components, nidogens largely functioning as catalysts or molecular adaptors and perlecan as bridging stabilizer. Collectively, orchestration of BM assembly, remodeling, and the role of individual players herein are determined by the developmental, tissue-specific, or functional context.

  11. 19-DEJ-1, a hemidesmosome-anchoring filament complex-associated monoclonal antibody. Definition of a new skin basement membrane antigenic defect in junctional and dystrophic epidermolysis bullosa

    DEFF Research Database (Denmark)

    Fine, J D; Horiguchi, Y; Couchman, J R

    1989-01-01

    A murine monoclonal antibody (19-DEJ-1) was recently produced that recognizes a unique antigenic epitope of human skin basement membrane localized to the midlamina lucida exclusively in those areas bordered by overlying hemidesmosomes. To determine whether the antigen defined by 19-DEJ-1 is norma...

  12. Near-ultraviolet radiation-induced lipid peroxidation and membrane effects in Escherichia coli and human skin fibroblasts

    International Nuclear Information System (INIS)

    Chamberlain, J.

    1987-01-01

    The first part of this thesis examines the response of an unsaturated fatty acid auxotroph, Escherichia coli K1060 to broad-band near-UV radiation. Sensitivity, lipid peroxidation and leakage of rubidium from irradiated cells were found to increase with increasing unsaturation of membrane fatty acids. The involvement of singlet oxygen was implicated by an increase in sensitivity, lipid peroxidation and leakage of rubidium following irradiation in deuterium oxide. Some factors influencing survival following irradiation were investigated, where lower growth rates were shown to enhance survival. In the second part, the study was extended to human fibroblasts where a normal human skin fibroblast strain, GM730 and a strain derived from an actinic reticuloid patient, AR6LO, are compared. Lipid peroxidation was measured in both cell lines following broad-band near-UV irradiation. Membrane activity, as assessed by the pinocytic uptake of 14 C-sucrose and its subsequent release from the cell, was measured. Near-UV irradiation was found to increase such activity in both strains. Vitamin E and Trolox-C were found to decrease this response in AR6LO but not GM730 cells. The final part consists of preliminary investigations into the near-UV induced peroxidation of fatty acids and liposomes, and the subsequent increase in the level of hydroperoxides in the hours following irradiation. (author)

  13. Vortex interactions in a two side-by-side cylinder near-wake

    International Nuclear Information System (INIS)

    Wang, Z.J.; Zhou, Y.

    2005-01-01

    The flow behind two side-by-side circular cylinders is experimentally investigated based on laser-illuminated flow-visualization, particle image velocimetry and hot-wire measurements. The flow is classified as three regimes: single street (the cylinder center-to-center spacing T/d 2.0). Special attention is given to the regime of 1.2 2.0, the flow structure change from the anti-phase to in-phase mode starts with a phase shift between gap vortices. The dynamical role of gap bleeding between cylinders for L/d < 1.2 is also examined

  14. Social long-term care insurance with two-sided altruism

    OpenAIRE

    Cremer, Helmuth; Pestieau, Pierre; Roeder, Kerstin

    2015-01-01

    This paper studies the design of a social long-term care (LTC) insurance when altruism is two-sided. The laissez-faire solution is not efficient, unless there is perfect altruism. Under full information, the first-best can be decentralized by a linear subsidy on informal aid, a linear tax on bequests when the parent is dependent and state specific lump-sum transfers which provide insurance. We also study a second-best scheme comprising a LTC benefit, a payroll tax on children's earnings and a...

  15. Two sides of the same coin? The (techno)epistemic cultures of systems and synthetic biology.

    Science.gov (United States)

    Kastenhofer, Karen

    2013-06-01

    Systems and synthetic biology both emerged around the turn of this century as labels for new research approaches. Although their disciplinary status as well as their relation to each other is rarely discussed in depth, now and again the idea is invoked that both approaches represent 'two sides of the same coin'. The following paper focuses on this general notion and compares it with empirical findings concerning the epistemic cultures prevalent in the two contexts. Drawing on interviews with researchers from both fields, on participatory observation in conferences and courses and on documentary analysis, this paper delineates differences and similarities, incompatibilities and blurred boundaries. By reconstructing systems and synthetic biology's epistemic cultures, this paper argues that they represent two 'communities of vision', encompassing heterogeneous practices. Understanding the relation of the respective visions of understanding nature and engineering life is seen as indispensible for the characterisation of (techno)science in more general terms. Depending on the conceptualisation of understanding and construction (or: science and engineering), related practices such as in silico modelling for enhancing understanding or enabling engineering can either be seen as incommensurable or 'two sides of one coin'. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Supercritical heat transfer in an annular channel with two-sided heaing

    International Nuclear Information System (INIS)

    Sergeev, V.V.; Remizov, O.V.; Gal'chenko, Eh.F.

    1986-01-01

    The paper deals with experimental inestigation into worsening of heat transfer at forced up flow in steam-water mixture in a vertical annular channel with two-sided heating and development of technique for calculation of supercritical heat exchange in this channel. Bench-scale experiments are carried out at high-pressure at mass rates of the coolant equal to 300-865 kg/(m 2 x s), pressure of 9.8-17.8 MPa and heat flux on the internal surface - 20-400 kW/m 2 , on the external surface - 35-450 kW/m 2 . Technique for calculation of supercritical heat exchange in channels with one- and two-sided heating is suggested. Analysis of the obtained experimental data permits to determine conditions for arising departure nucleate boiling on the internal and external surfaces and on both surfaces simultaneously. It is concluded that the suggested technique of calculation adequately reflects the effect of regime parameters of coolant flow on temperature regime of heat transferring surfaces in the supercritical area

  17. Contact curietherapy with 32P used in diseases of the skin and visible mucous membranes

    International Nuclear Information System (INIS)

    Vlakhov, N.; Gyrdev, P.; Parusheva, D.

    1994-01-01

    Contact curietherapy with 32 P is conducted in sixty-one patients affected with keratoma senile (34), leukoplakia vulvae (15), chronic eczema (10), Bowen's disease (1) and Queyrat's disease (1). A contact technique with applicator is used. The single skin dose amounts to 5 Gy/hour. Irradiation rhythm is: alternating 5 consecutive days with 2 days rest period. The total dose per course leading to a permanent therapeutic effect (3 years) varies in the range 35 to 100 Gy/h. Optimal results are recorded in 42% of cases, very good - in 52%, and satisfactory - in 6%. A wider application of the method in hematological practice is recommended because of the low radiation exposure and absence of complications. 12 refs. (orig.)

  18. Melatonin reverses the enhanced oxidative damage to membrane lipids and improves skin biophysical characteristics in former-smokers - A study in postmenopausal women.

    Science.gov (United States)

    Sagan, Dorota; Stepniak, Jan; Gesing, Adam; Lewinski, Andrzej; Karbownik-Lewinska, Malgorzata

    2017-12-23

    Protective antioxidative effects of melatonin have been repeatedly documented in experimental and clinical studies. One of the most spectacular exogenous prooxidative agents is cigarette smoking. The aim of the study was to evaluate the level of oxidative damage to membrane lipids (lipid peroxidation; LPO) in blood serum, and in epidermis exfoliated during microdermabrasion collected from former-smokers who were treated with melatonin. The study was performed in postmenopausal women. Ninety (90) female volunteers, aged 46-67 years, were enrolled. Two major groups, i.e. never-smokers (n=44) and former-smokers (n=46), were divided into: Control, melatonin topical skin application, Restructurer (containing antioxidants) topical skin application, and melatonin oral treatment. Microdermabrasion was performed at point '0', after 2 weeks, and after 4 weeks of treatment. The following parameters were measured: LPO in blood serum, LPO in epidermis exfoliated during microdermabrasion, and skin biophysical characteristics, such as sebum, moisture, elasticity, and pigmentation. Malondialdehyde+4-hydroxyalkenals level (LPO index) was measured spectrophotometrically. Melatonin oral treatment significantly reversed the increased serum LPO level in former-smokers already after 2 weeks of treatment. In a univariate regression model, LPO blood level constituted the only independent factor negatively associated with melatonin oral treatment. After 4 weeks of treatment, melatonin given orally increased skin sebum, moisture and elasticity levels, and melatonin applied topically increased sebum level. Exogenous melatonin reverses the enhanced oxidative damage to membrane lipids and improves skin biophysical characteristics in former-smokers.

  19. Two sides of the same coin: stem cells in cancer and regenerative medicine.

    Science.gov (United States)

    Ilmer, Matthias; Vykoukal, Jody; Recio Boiles, Alejandro; Coleman, Michael; Alt, Eckhard

    2014-07-01

    Multipotent stromal cells (MSCs) derived from bone marrow, adipose tissue, cord blood, and other origins have recently received much attention as potential therapeutic agents with beneficial immunomodulatory and regenerative properties. In their native tissue environment, however, such cells also appear to have essential functions in building and supporting tumor microenvironments, providing metastatic niches, and maintaining cancer hallmarks. Here, we consider the varied roles of these tissue-resident stroma-associated cells, synthesize recent and emerging discoveries, and discuss the role, potential, and clinical applications of MSCs in cancer and regenerative medicine.-Ilmer, M., Vykoukal, J., Recio Boiles, A., Coleman, M., Alt, E. Two sides of the same coin: stem cells in cancer and regenerative medicine. © FASEB.

  20. Numerical study of two side-by-side cylinders with unequal diameters at low Reynolds number

    International Nuclear Information System (INIS)

    Gao, Y Y; Wang, X K; Tan, S K

    2012-01-01

    Two-dimensional laminar flow about two side-by-side unequal cylinders with different diameter ratios d/D and centre-to-centre spacing ratios T/D at Re=300 (based on the larger cylinder diameter) was simulated using a CFD software. Comparisons of experimental and numerical results were made to elucidate the degree of interference due to d/D and T/D and their effects on the flow patterns and vortex shedding frequencies. The findings showed that the flow patterns behind two unequal cylinders were distinctly different from that behind two equal side-by-side cylinders, with distinct in-phase and anti-phase vortex shedding, and random switching of modes of vortex shedding.

  1. Slip effects on a generalized Burgers’ fluid flow between two side walls with fractional derivative

    Directory of Open Access Journals (Sweden)

    Shihao Han

    2016-01-01

    Full Text Available This paper presents a research for the 3D flow of a generalized Burgers’ fluid between two side walls generated by an exponential accelerating plate and a constant pressure gradient, where the no-slip assumption between the exponential accelerating plate and the Burgers’ fluid is no longer valid. The governing equations of the generalized Burgers’ fluid flow are established by using the fractional calculus approach. Exact analytic solutions for the 3D flow are established by employing the Laplace transform and the finite Fourier sine transform. Furthermore, some 3D and 2D figures for the fluid velocity and shear stress are plotted to analyze and discuss the effects of various parameters.

  2. Multi-Robot Item Delivery and Foraging: Two Sides of a Coin

    Directory of Open Access Journals (Sweden)

    Somchaya Liemhetcharat

    2015-09-01

    Full Text Available Multi-robot foraging has been widely studied in the literature, and the general assumption is that the robots are simple, i.e., with limited processing and carrying capacity. We previously studied continuous foraging with slightly more capable robots, and in this article, we are interested in using similar robots for item delivery. Interestingly, item delivery and foraging are two sides of the same coin: foraging an item from a location is similar to satisfying a demand. We formally define the multi-robot item delivery problem and show that the continuous foraging problem is a special case of it. We contribute distributed multi-robot algorithms that solve the item delivery and foraging problems and describe how our shared world model is synchronized across the multi-robot team. We performed extensive experiments on simulated robots using a Java simulator, and we present our results to demonstrate that we outperform benchmark algorithms from multi-robot foraging.

  3. End Effects on the Linear Induction MHD Generator Calculated by Two-Sided Laplace Transform

    Energy Technology Data Exchange (ETDEWEB)

    Engeln, F.; Peschka, W. [Deutsche Versuchsanstalt fuer Luft- und Raumfahrt e.V., Institut fuer Energiewandlung und Elektrische Antriebe, Stuttgart, Federal Republic of Germany (Germany)

    1966-11-15

    In induction MHD systems special problems occur where the flow enters or leaves the magnetic field. These problems are generally described as end effects. Large gradients of the magnetic field are present at the inlet and also at the outlet of an MHD induction engine, these generating electric current systems in the fluid which may spoil the performance characteristics of the generator due to the interaction with the primary field of the engine. The two-dimensional induction MHD generator of finite length, using a polyphase winding system to obtain a travelling magnetic field, is treated as a boundary value problem by two-sided Laplace transform. For simplicity incompressibility is assumed. The two- dimensional boundary value problem of the induction engine is solved for - {infinity} Less-Than-Over-Equal-To x Less-Than-Over-Equal-To {infinity}. x is parallel to the flow direction of the linear MHD generator. In the region 0 Less-Than-Over-Equal-To x Less-Than-Over-Equal-To L the magnetic travelling wave is sinusoidal with a cyclical frequency {omega} and a phase-velocity v{sub s}. At x = 0 the conducting incompressible working fluid enters the field region and leaves it at the point-x = L. Two mathematical methods can be used to solve the boundary value problem, the Fourier transform or the two-sided Laplace transform. The latter offers the advantage of representing a complex analytical function in the image space. Moreover, it is possible to obtain the characteristics of the generator in the image space (e. g. field configuration, power flow function, etc.). That implies a large simplification of mathematical treatment. The solution in the original space then is given by asymptotic expansion of the known image function. (author)

  4. Basement membrane reconstruction in human skin equivalents is regulated by fibroblasts and/or exogenously activated keratinocytes.

    Science.gov (United States)

    El Ghalbzouri, Abdoelwaheb; Jonkman, Marcel F; Dijkman, Remco; Ponec, Maria

    2005-01-01

    This study was undertaken to examine the role fibroblasts play in the formation of the basement membrane (BM) in human skin equivalents. For this purpose, keratinocytes were seeded on top of fibroblast-free or fibroblast-populated collagen matrix or de-epidermized dermis and cultured in the absence of serum and exogenous growth factors. The expression of various BM components was analyzed on the protein and mRNA level. Irrespective of the presence or absence of fibroblasts, keratin 14, hemidesmosomal proteins plectin, BP230 and BP180, and integrins alpha1beta1, alpha2beta1, alpha3beta1, and alpha6beta4 were expressed but laminin 1 was absent. Only in the presence of fibroblasts or of various growth factors, laminin 5 and laminin 10/11, nidogen, uncein, type IV and type VII collagen were decorating the dermal/epidermal junction. These findings indicate that the attachment of basal keratinocytes to the dermal matrix is most likely mediated by integrins alpha1beta1 and alpha2beta1, and not by laminins that bind to integrin alpha6beta4 and that the epithelial-mesenchymal cross-talk plays an important role in synthesis and deposition of various BM components.

  5. How to optimize brand awareness through non-administrated social channels in a two-sided network

    OpenAIRE

    Arozin, Alexander

    2016-01-01

    The effects of social media on digital branding is analysed in this paper, to establish how to optimize brand awareness through non-administrated social media channels in a two-sided network. This is a relatively unexplored field which may prove to be important for future businesses. Different levels of cooperation between brands are increasing and the implementation of two-sided networks are becoming standardized. A new way of differentiation is needed for the ever changing field of social m...

  6. Translation failure and medical reversal: Two sides to the same coin.

    Science.gov (United States)

    Prasad, Vinay

    2016-01-01

    Translation failure occurs when the results of preclinical, observational and/or early phase studies fail to predict the results of well done (i.e. appropriately controlled, adequately powered, and properly conducted) phase III or randomised clinical trials. Some failures occur when promising basic science findings fail to replicate in human studies, while others happen when promising uncontrolled trial data show an exaggerated effect that vanishes in the setting of a randomised trial. Medical reversals occur when the results of preclinical, observational and/or early phase studies fail to predict the results of subsequent randomized clinical trials, but the practice has already gained widespread acceptance. Oncologic examples include bevacizumab and the use of autologous stem cell transplant in metastatic breast cancer. In a well-intentioned effort to reduce the rate of translation failure, oncologists must be careful that changes to regulatory processes and clinical trial design do not actually work to increase the approval of ineffective compounds. By trying to cure translation failure, we should be careful to avoid medical reversal. The rise of surrogate end-points and role of hard-wired bias in oncology trials suggest that we may be currently ignoring the simple fact that translation failure and medical reversal are two sides to the same coin. Published by Elsevier Ltd.

  7. Accurately bi-orthogonal direct and adjoint lambda modes via two-sided Eigen-solvers

    International Nuclear Information System (INIS)

    Roman, J.E.; Vidal, V.; Verdu, G.

    2005-01-01

    This work is concerned with the accurate computation of the dominant l-modes (Lambda mode) of the reactor core in order to approximate the solution of the neutron diffusion equation in different situations such as the transient modal analysis. In a previous work, the problem was already addressed by implementing a parallel program based on SLEPc (Scalable Library for Eigenvalue Problem Computations), a public domain software for the solution of eigenvalue problems. Now, the proposed solution is extended by incorporating also the computation of the adjoint l-modes in such a way that the bi-orthogonality condition is enforced very accurately. This feature is very desirable in some types of analyses, and in the proposed scheme it is achieved by making use of two-sided eigenvalue solving software. Current implementations of some of these software, while still susceptible of improvement, show that they can be competitive in terms of response time and accuracy with respect to other types of eigenvalue solving software. The code developed by the authors has parallel capabilities in order to be able to analyze reactors with a great level of detail in a short time. (authors)

  8. Two-Sided Estimates of Thermo-elastic Characteristics of Dispersed Inclusion Composites

    Directory of Open Access Journals (Sweden)

    V. S. Zarubin

    2015-01-01

    Full Text Available The composites, dispersion-reinforced with inclusions from high-strength and high-modulus materials are widely used in technology. Nanostructure elements can perform the role of such inclusions as well. Possible applications of such composites in heat-stressed structures under heavy mechanical and thermal influences significantly depend on a complex of thermo-mechanical characteristics including the values of the moduli of elasticity and coefficient of linear thermal expansion. There are different approaches to construction of mathematical models that allow calculating dependences to estimate elastic characteristics of composites. Relation between thermoelastic properties of matrix and inclusions of the composite with its temperature coefficient of linear expansion is studied in less detail. Thus, attention has been insufficient in estimating a degree of reliability and a possible error of derived dependencies.A dual variation formulation of the problem of thermo-elasticity in a non-uniform solids simulating the properties and structure of the composite with dispersed inclusions, makes it possible to define two-sided limits of possible values of the volume elasticity modulus, shear modulus, and coefficient of linear thermal expansion of such composite. These limits allow us to estimate the maximum possible error, if to take a half-sum of the limit values of these parameters as the thermoelastic characteristics of the composite. Implementing this approach to find possible errors, arising when using one or another calculating dependency, improves reliability of predicted thermo-elastic characteristics as applied to existing and promising composites.

  9. Thickness measurement by two-sided step-heating thermal imaging

    Science.gov (United States)

    Li, Xiaoli; Tao, Ning; Sun, J. G.; Zhang, Cunlin; Zhao, Yuejin

    2018-01-01

    Infrared thermal imaging is a promising nondestructive technique for thickness prediction. However, it is usually thought to be only appropriate for testing the thickness of thin objects or near-surface structures. In this study, we present a new two-sided step-heating thermal imaging method which employed a low-cost portable halogen lamp as the heating source and verified it with two stainless steel step wedges with thicknesses ranging from 5 mm to 24 mm. We first derived the one-dimensional step-heating thermography theory with the consideration of warm-up time of the lamp, and then applied the nonlinear regression method to fit the experimental data by the derived function to determine the thickness. After evaluating the reliability and accuracy of the experimental results, we concluded that this method is capable of testing thick objects. In addition, we provided the criterions for both the required data length and the applicable thickness range of the testing material. It is evident that this method will broaden the thermal imaging application for thickness measurement.

  10. Accurately bi-orthogonal direct and adjoint lambda modes via two-sided Eigen-solvers

    Energy Technology Data Exchange (ETDEWEB)

    Roman, J.E.; Vidal, V. [Valencia Univ. Politecnica, D. Sistemas Informaticos y Computacion (Spain); Verdu, G. [Valencia Univ. Politecnica, D. Ingenieria Quimica y Nuclear (Spain)

    2005-07-01

    This work is concerned with the accurate computation of the dominant l-modes (Lambda mode) of the reactor core in order to approximate the solution of the neutron diffusion equation in different situations such as the transient modal analysis. In a previous work, the problem was already addressed by implementing a parallel program based on SLEPc (Scalable Library for Eigenvalue Problem Computations), a public domain software for the solution of eigenvalue problems. Now, the proposed solution is extended by incorporating also the computation of the adjoint l-modes in such a way that the bi-orthogonality condition is enforced very accurately. This feature is very desirable in some types of analyses, and in the proposed scheme it is achieved by making use of two-sided eigenvalue solving software. Current implementations of some of these software, while still susceptible of improvement, show that they can be competitive in terms of response time and accuracy with respect to other types of eigenvalue solving software. The code developed by the authors has parallel capabilities in order to be able to analyze reactors with a great level of detail in a short time. (authors)

  11. Towards Automated Bargaining in Electronic Markets: A Partially Two-Sided Competition Model

    Science.gov (United States)

    Gatti, Nicola; Lazaric, Alessandro; Restelli, Marcello

    This paper focuses on the prominent issue of automating bargaining agents within electronic markets. Models of bargaining in literature deal with settings wherein there are only two agents and no model satisfactorily captures settings in which there is competition among buyers, being they more than one, and analogously among sellers. In this paper, we extend the principal bargaining protocol, i.e. the alternating-offers protocol, to capture bargaining in markets. The model we propose is such that, in presence of a unique buyer and a unique seller, agents' equilibrium strategies are those in the original protocol. Moreover, we game theoretically study the considered game providing the following results: in presence of one-sided competition (more buyers and one seller or vice versa) we provide agents' equilibrium strategies for all the values of the parameters, in presence of two-sided competition (more buyers and more sellers) we provide an algorithm that produce agents' equilibrium strategies for a large set of the parameters and we experimentally evaluate its effectiveness.

  12. Evaluation of the membrane permeability (PAMPA and skin) of benzimidazoles with potential cannabinoid activity and their relation with the Biopharmaceutics Classification System (BCS).

    Science.gov (United States)

    Alvarez-Figueroa, M Javiera; Pessoa-Mahana, C David; Palavecino-González, M Elisa; Mella-Raipán, Jaime; Espinosa-Bustos, Cristián; Lagos-Muñoz, Manuel E

    2011-06-01

    The permeability of five benzimidazole derivates with potential cannabinoid activity was determined in two models of membranes, parallel artificial membrane permeability assay (PAMPA) and skin, in order to study the relationship of the physicochemical properties of the molecules and characteristics of the membranes with the permeability defined by the Biopharmaceutics Classification System. It was established that the PAMPA intestinal absorption method is a good predictor for classifying these molecules as very permeable, independent of their thermodynamic solubility, if and only if these have a Log P(oct) value permeability is conditioned on the solubility of the molecule so that it can only serve as a model for classifying the permeability of molecules that possess high solubility (class I: high solubility, high permeability; class III: high solubility, low permeability).

  13. Balsam-Pear-Skin-Like Porous Polyacrylonitrile Nanofibrous Membranes Grafted with Polyethyleneimine for Postcombustion CO2 Capture.

    Science.gov (United States)

    Zhang, Yufei; Guan, Jiming; Wang, Xianfeng; Yu, Jianyong; Ding, Bin

    2017-11-22

    Amine-containing sorbents have been extensively studied for postcombustion carbon dioxide (CO 2 ) capture because of their ability to chemisorb CO 2 from the flue gas. However, most sorbents are in the form of powders currently, which is not the ideal configuration for the flue gas separation because of the fragile nature and poor mechanical properties, resulting in blocking of the flow pipes and difficult recycling. Herein, we present a novel approach for the facile fabrication of flexible, robust, and polyethyleneimine-grafted (PEI-grafted) hydrolyzed porous PAN nanofibrous membranes (HPPAN-PEI NFMs) through the combination of electrospinning, pore-forming process, hydrolysis reaction, and the subsequent grafting technique. Excitingly, we find that all the resultant porous PAN (PPAN) fibers exhibit a balsam-pear-skin-like porous structure due to the selective removal of poly(vinylpyrrolidone) (PVP) from PAN/PVP fibers by water extraction. Significantly, the HPPAN-PEI NFMs retain their mesoporosity, as well as exhibit good thermal stability and prominent tensile strength (11.1 MPa) after grafting, guaranteeing their application in CO 2 trapping from the flue gas. When exposed to CO 2 at 40 °C, the HPPAN-PEI NFMs show an enhanced CO 2 adsorption capacity of 1.23 mmol g -1 (based on the overall quantity of the sample) or 6.15 mmol g -1 (based on the quantity of grafted PEI). Moreover, the developed HPPAN-PEI NFMs display significantly selective capture for CO 2 over N 2 and excellent recyclability. The CO 2 capacity retains 92% of the initial value after 20 adsorption-desorption cycle tests, indicating that the resultant HPPAN-PEI NFMs have good long-term stability. This work paves the way for fabricating NFM-based solid adsorption materials endowed with a porous structure applied to efficient postcombustion CO 2 capture.

  14. Immunosenescence and Inflamm-Aging As Two Sides of the Same Coin: Friends or Foes?

    Science.gov (United States)

    Fulop, Tamas; Larbi, Anis; Dupuis, Gilles; Le Page, Aurélie; Frost, Eric H; Cohen, Alan A; Witkowski, Jacek M; Franceschi, Claudio

    2017-01-01

    The immune system is the most important protective physiological system of the organism. It has many connections with other systems and is, in fact, often considered as part of the larger neuro-endocrine-immune axis. Most experimental data on immune changes with aging show a decline in many immune parameters when compared to young healthy subjects. The bulk of these changes is termed immunosenescence. Immunosenescence has been considered for some time as detrimental because it often leads to subclinical accumulation of pro-inflammatory factors and inflamm-aging. Together, immunosenescence and inflamm-aging are suggested to stand at the origin of most of the diseases of the elderly, such as infections, cancer, autoimmune disorders, and chronic inflammatory diseases. However, an increasing number of immune-gerontologists have challenged this negative interpretation of immunosenescence with respect to its significance in aging-related alterations of the immune system. If one considers these changes from an evolutionary perspective, they can be viewed preferably as adaptive or remodeling rather than solely detrimental. Whereas it is conceivable that global immune changes may lead to various diseases, it is also obvious that these changes may be needed for extended survival/longevity. Recent cumulative data suggest that, without the existence of the immunosenescence/inflamm-aging duo (representing two sides of the same phenomenon), human longevity would be greatly shortened. This review summarizes recent data on the dynamic reassessment of immune changes with aging. Accordingly, attempts to intervene on the aging immune system by targeting its rejuvenation, it may be more suitable to aim to maintain general homeostasis and function by appropriately improving immune-inflammatory-functions.

  15. Immunosenescence and Inflamm-Aging As Two Sides of the Same Coin: Friends or Foes?

    Science.gov (United States)

    Fulop, Tamas; Larbi, Anis; Dupuis, Gilles; Le Page, Aurélie; Frost, Eric H.; Cohen, Alan A.; Witkowski, Jacek M.; Franceschi, Claudio

    2018-01-01

    The immune system is the most important protective physiological system of the organism. It has many connections with other systems and is, in fact, often considered as part of the larger neuro–endocrine–immune axis. Most experimental data on immune changes with aging show a decline in many immune parameters when compared to young healthy subjects. The bulk of these changes is termed immunosenescence. Immunosenescence has been considered for some time as detrimental because it often leads to subclinical accumulation of pro-inflammatory factors and inflamm-aging. Together, immunosenescence and inflamm-aging are suggested to stand at the origin of most of the diseases of the elderly, such as infections, cancer, autoimmune disorders, and chronic inflammatory diseases. However, an increasing number of immune-gerontologists have challenged this negative interpretation of immunosenescence with respect to its significance in aging-related alterations of the immune system. If one considers these changes from an evolutionary perspective, they can be viewed preferably as adaptive or remodeling rather than solely detrimental. Whereas it is conceivable that global immune changes may lead to various diseases, it is also obvious that these changes may be needed for extended survival/longevity. Recent cumulative data suggest that, without the existence of the immunosenescence/inflamm-aging duo (representing two sides of the same phenomenon), human longevity would be greatly shortened. This review summarizes recent data on the dynamic reassessment of immune changes with aging. Accordingly, attempts to intervene on the aging immune system by targeting its rejuvenation, it may be more suitable to aim to maintain general homeostasis and function by appropriately improving immune-inflammatory-functions. PMID:29375577

  16. Indirect two-sided relative ranking: a robust similarity measure for gene expression data

    Directory of Open Access Journals (Sweden)

    Licamele Louis

    2010-03-01

    Full Text Available Abstract Background There is a large amount of gene expression data that exists in the public domain. This data has been generated under a variety of experimental conditions. Unfortunately, these experimental variations have generally prevented researchers from accurately comparing and combining this wealth of data, which still hides many novel insights. Results In this paper we present a new method, which we refer to as indirect two-sided relative ranking, for comparing gene expression profiles that is robust to variations in experimental conditions. This method extends the current best approach, which is based on comparing the correlations of the up and down regulated genes, by introducing a comparison based on the correlations in rankings across the entire database. Because our method is robust to experimental variations, it allows a greater variety of gene expression data to be combined, which, as we show, leads to richer scientific discoveries. Conclusions We demonstrate the benefit of our proposed indirect method on several datasets. We first evaluate the ability of the indirect method to retrieve compounds with similar therapeutic effects across known experimental barriers, namely vehicle and batch effects, on two independent datasets (one private and one public. We show that our indirect method is able to significantly improve upon the previous state-of-the-art method with a substantial improvement in recall at rank 10 of 97.03% and 49.44%, on each dataset, respectively. Next, we demonstrate that our indirect method results in improved accuracy for classification in several additional datasets. These datasets demonstrate the use of our indirect method for classifying cancer subtypes, predicting drug sensitivity/resistance, and classifying (related cell types. Even in the absence of a known (i.e., labeled experimental barrier, the improvement of the indirect method in each of these datasets is statistically significant.

  17. 23andMe: a new two-sided data-banking market model.

    Science.gov (United States)

    Stoeklé, Henri-Corto; Mamzer-Bruneel, Marie-France; Vogt, Guillaume; Hervé, Christian

    2016-03-31

    Since 2006, the genetic testing company 23andMe has collected biological samples, self-reported information, and consent documents for biobanking and research from more than 1,000,000 individuals (90% participating in research), through a direct-to-consumer (DTC) online genetic-testing service providing a genetic ancestry report and a genetic health report. However, on November 22, 2013, the Food and Drug Administration (FDA) halted the sale of genetic health testing, on the grounds that 23andMe was not acting in accordance with federal law, by selling tests of undemonstrated reliability as predictive tests for medical risk factors. Consumers could still obtain the genetic ancestry report, but they no longer had access to the genetic health report in the United States (US). However, this did not prevent the company from continuing its health research, with previously obtained and future samples, provided that consent had been obtained from the consumers concerned, or with health reports for individuals from other countries. Furthermore, 23andMe was granted FDA authorization on February 19, 2015, first to provide reports about Bloom syndrome carrier status, and, more recently, to provide consumers with "carrier status" information for 35 genes known (with high levels of confidence) to cause disease. In this Debate, we highlight the likelihood that the primary objective of the company was probably two-fold: promoting itself within the market for predictive testing for human genetic diseases and ancestry at a low cost to consumers, and establishing a high-value database/biobank for research (one of the largest biobanks of human deoxyribonucleic acid (DNA) and personal information). By dint of this marketing approach, a two-sided market has been established between the consumer and the research laboratories, involving the establishment of a database/DNA biobank for scientific and financial gain. We describe here the profound ethical issues raised by this setup.

  18. Topical application of zinc oxide nanoparticles reduces bacterial skin infection in mice and exhibits antibacterial activity by inducing oxidative stress response and cell membrane disintegration in macrophages.

    Science.gov (United States)

    Pati, Rashmirekha; Mehta, Ranjit Kumar; Mohanty, Soumitra; Padhi, Avinash; Sengupta, Mitali; Vaseeharan, Baskarlingam; Goswami, Chandan; Sonawane, Avinash

    2014-08-01

    Here we studied immunological and antibacterial mechanisms of zinc oxide nanoparticles (ZnO-NPs) against human pathogens. ZnO-NPs showed more activity against Staphylococcus aureus and least against Mycobacterium bovis-BCG. However, BCG killing was significantly increased in synergy with antituberculous-drug rifampicin. Antibacterial mechanistic studies showed that ZnO-NPs disrupt bacterial cell membrane integrity, reduce cell surface hydrophobicity and down-regulate the transcription of oxidative stress-resistance genes in bacteria. ZnO-NP treatment also augmented the intracellular bacterial killing by inducing reactive oxygen species production and co-localization with Mycobacterium smegmatis-GFP in macrophages. Moreover, ZnO-NPs disrupted biofilm formation and inhibited hemolysis by hemolysin toxin producing S. aureus. Intradermal administration of ZnO-NPs significantly reduced the skin infection, bacterial load and inflammation in mice, and also improved infected skin architecture. We envision that this study offers novel insights into antimicrobial actions of ZnO-NPs and also demonstrates ZnO-NPs as a novel class of topical anti-infective agent for the treatment of skin infections. This in-depth study demonstrates properties of ZnO nanoparticles in infection prevention and treatment in several skin infection models, dissecting the potential mechanisms of action of these nanoparticles and paving the way to human applications. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Matriptase and prostasin are expressed in human skin in an inverse trend over the course of differentiation and are targeted to different regions of the plasma membrane

    Directory of Open Access Journals (Sweden)

    Chih-Hsin Lai

    2016-10-01

    Full Text Available Matriptase and prostasin, acting as a tightly coupled proteolytic cascade, were reported to be required for epidermal barrier formation in mouse skin. Here we show that, in human skin, matriptase and prostasin are expressed with an inverse pattern over the course of differentiation. Matriptase was detected primarily in epidermal basal keratinocytes and the basaloid cells in the outer root sheath of hair follicles and the sebaceous gland, where prostasin was not detected. In contrast, prostasin was detected primarily in differentiated cells in the epidermal granular layer, the inner root sheath of hair follicles, and the sebaceous gland, where matriptase expression is negligible. While co-expressed in the middle stage of differentiation, prostasin was detected as polarized patches, and matriptase at intercellular junctions. Targeting to different subcellular localizations is also observed in HaCaT human keratinocytes, in which matriptase was detected primarily at intercellular junctions, and prostasin primarily on membrane protrusion. Furthermore, upon induction of zymogen activation, free active prostasin remains cell-associated and free active matriptase is rapidly shed into the extracellular milieu. Our data suggest that matriptase and prostasin likely function as independent entities in human skin rather than as a tightly coupled proteolytic cascade as observed in mouse skin.

  20. [Occurrence and number of bacteria from the Micrococcus, Kocuria, Nesterenkonia, Kytococcus and Dermacoccus genera on skin and mucous membranes in humans].

    Science.gov (United States)

    Szczerba, Izabela

    2003-01-01

    The aim of work was to evaluate the frequency of occurrence of bacteria from genera of Micrococcus, Kocuria, Nesterenkonia, kytococcus and Dermatococcus on human skin and mucous membranes in healthy population. Among 150 investigated persons these bacteria were found in 122 (81.3%). The frequency of isolation was similar in both sex (82.4% in female and 79.7% in male). Most often the strains were isolated from oral cavity (48.7%), and from skin of palm and forearm (40.7% and 37.3%). Least frequency of occurrence was observed in vestibule of nose (26%). The predominant isolated strains were: M. luteus (26.2%), and N. halobia (21%) followed by K. varians (16.4%), M. lylae (12.2%), D. sedentarius (9.1%), K. kristinae (7.3%), K. nishinomiyaensis (7.3%), K. rosea (0.3%).

  1. NKG2D Ligands in Tumor Immunity: Two Sides of a Coin

    Directory of Open Access Journals (Sweden)

    Jennifer eWu

    2015-03-01

    Full Text Available The activating/co-stimulatory receptor NKG2D (natural-killer group 2, member D is expressed on the surface of all human NK, NKT, CD8+ T and subsets of γδ+ T cells. The significance of NKG2D function in tumor immunity has been well demonstrated in experimental animal models. However, the role of human NKG2D ligands in regulating tumor immunity and cancer prognosis had been controversial in the literature. In this review, we summarize the latest advancement, discuss the controversies, and present evidence that membrane-bound and soluble NKG2D ligands oppositely regulate tumor immunity. We also discuss new perspectives of targeting NKG2D ligands for cancer immunotherapy.

  2. Membranous nephropathy

    Science.gov (United States)

    ... skin-lightening creams Systemic lupus erythematosus , rheumatoid arthritis, Graves disease, and other autoimmune disorders The disorder occurs at ... diagnosis. The following tests can help determine the cause of membranous nephropathy: Antinuclear antibodies test Anti-double- ...

  3. Assessing unilateral merger effects in a two-sided market : An application to the Dutch daily newspaper market

    NARCIS (Netherlands)

    Filistrucchi, L.; Klein, T.J.; Michielsen, T.O.

    2012-01-01

    We compare different methods to assess unilateral merger effects in a two-sided market by applying them to a hypothetical merger in the Dutch newspaper industry. We first specify and estimate a structural model of demand for differentiated products in both the readership and the advertising sides of

  4. Assessing Unilateral Merger Effects in a Two-Sided Market : An Application to the Dutch Daily Newspaper Market

    NARCIS (Netherlands)

    Filistrucchi, L.; Klein, T.J.; Michielsen, T.O.

    2011-01-01

    We compare different methods to assess unilateral merger effects in a two-sided market by applying them to a hypothetical merger in the Dutch newspaper industry. For this, we first specify and estimate a structural model of demand for differentiated products on both the readership and the

  5. Intestinal Behçet and Crohn's disease: two sides of the same coin.

    Science.gov (United States)

    Valenti, Simona; Gallizzi, Romina; De Vivo, Dominique; Romano, Claudio

    2017-04-20

    Behçet's disease (BD) and Crohn's disease (CD) are chronic immune-mediated, inflammatory disorders affecting many different systems (joints, skin, eyes, gastrointestinal and biliary tracts). Both disorders have fluctuating courses and when gastrointestinal symptoms are prevalent, differential diagnosis can be difficult. BD involves the gastrointestinal tract in 10-15% of cases with localized lesions in the ileocecal region. The clinical picture is heterogeneous with various clusters of disease expression. CD is a chronic inflammatory disorder, which can affect any part of the intestinal tract, as well as extra-intestinal tissue. Factors that contribute towards the pathogenesis of both disease include the host's genetic profile, and immune system, and environmental factors such as the gut microbiota. The aim of this manuscript is to provide a narrative review of clinical features of BD and CD, highlighting the importance of differential diagnosis and therapeutic approach, especially in the presence of gastrointestinal involvement. A comprehensive search of published literature using the Pubmed ( http://www.ncbi.nlm.nih.gov/pubmed/ ) database was carried out to identify all articles published in English from 1999 to October 2016, using 4 key terms: "Behçet Disease", "Intestinal Behçet's Disease", "Crohn's Disease" and" Inflammatory Bowel Disease".

  6. Two sides of the coin. Part 2. Colloid and surface science meets real biointerfaces.

    Science.gov (United States)

    Ninham, Barry W; Larsson, Kåre; Lo Nostro, Pierandrea

    2017-11-01

    Part 1 revisited developments in lipid and surfactant self assembly over the past 40 years [1]. New concepts emerged. Here we explore how these developments can be used to make sense of and bring order to a range of complex biological phenomena. Together with Part 1, this contribution is a fundamental revision of intuition at the boundaries of Colloid Science and Biological interfaces from a perspective of nearly 50 years. We offer new insights on a unified treatment of self assembly of lipids, surfactants and proteins in the light of developments presented in Part 1. These were in the enabling disciplines in molecular forces, hydration, oil and electrolyte specificity; and in the role of non Euclidean geometries-across the whole gammut of physical, colloid and surface chemistry, biophysics and membrane biology and medicine. It is where the early founders of the cell theory of biology and the physiologists expected advances to occur as D'Arcy Thompson predicted us 100 years ago. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Two sides of the coin. Part 1. Lipid and surfactant self-assembly revisited.

    Science.gov (United States)

    Ninham, Barry W; Larsson, Kåre; Lo Nostro, Pierandrea

    2017-04-01

    Hofmeister, specific ion effects, hydration and van der Waals forces at and between interfaces are factors that determine curvature and microstructure in self assembled aggregates of surfactants and lipids; and in microemulsions. Lipid and surfactant head group interactions and between aggregates vary enormously and are highly specific. They act on the hydrophilic side of a bilayer, micelle or other self assembled aggregate. It is only over the last three decades that the origin of Hofmeister effects has become generally understood. Knowledge of their systematics now provides much flexibility in designing nanostructured fluids. The other side of the coin involves equally specific forces. These (opposing) forces work on the hydrophobic side of amphiphilic interfaces. They are due to the interaction of hydrocarbons and other "oils" with hydrophobic tails of surfactants and lipids. The specificity of oleophilic solutes in microemulsions and lipid membranes provides a counterpoint to Hofmeister effects and hydration. Together with global packing constraints these effects determine microstructure. Another factor that has hardly been recognised is the role of dissolved gas. This introduces further, qualitative changes in forces that prescribe microstructure. The systematics of these effects and their interplay are elucidated. Awareness of these competing factors facilitates formulation of self assembled nanostructured fluids. New and predictable geometries that emerge naturally provide insights into a variety of biological phenomena like anaesthetic and pheromone action and transmission of the nervous impulse (see Part 2). Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Chlamydia trachomatis Infection and Anti-Hsp60 Immunity: The Two Sides of the Coin

    Science.gov (United States)

    Cappello, Francesco; Conway de Macario, Everly; Di Felice, Valentina; Zummo, Giovanni; Macario, Alberto J. L.

    2009-01-01

    Chlamydia trachomatis (CT) infection is one of the most common causes of reproductive tract diseases and infertility. CT-Hsp60 is synthesized during infection and is released in the bloodstream. As a consequence, immune cells will produce anti-CT-Hsp60 antibodies. Hsp60, a ubiquitous and evolutionarily conserved chaperonin, is normally sequestered inside the cell, particularly into mitochondria. However, upon cell stress, as well as during carcinogenesis, the chaperonin becomes exposed on the cell surface (sf-Hsp60) and/or is secreted from cells into the extracellular space and circulation. Reports in the literature on circulating Hsp and anti-Hsp antibodies are in many cases short on details about Hsp60 concentrations, and about the specificity spectra of the antibodies, their titers, and their true, direct, pathogenetic effects. Thus, more studies are still needed to obtain a definitive picture on these matters. Nevertheless, the information already available indicates that the concurrence of persistent CT infection and appearance of sf-Hsp60 can promote an autoimmune aggression towards stressed cells and the development of diseases such as autoimmune arthritis, multiple sclerosis, atherosclerosis, vasculitis, diabetes, and thyroiditis, among others. At the same time, immunocomplexes composed of anti-CT-Hsp60 antibodies and circulating Hsp60 (both CT and human) may form deposits in several anatomical locations, e.g., at the glomerular basal membrane. The opposite side of the coin is that pre-tumor and tumor cells with sf-Hsp60 can be destroyed with participation of the anti-Hsp60 antibody, thus stopping cancer progression before it is even noticed by the patient or physician. PMID:19714222

  9. Chlamydia trachomatis infection and anti-Hsp60 immunity: the two sides of the coin.

    Directory of Open Access Journals (Sweden)

    Francesco Cappello

    2009-08-01

    Full Text Available Chlamydia trachomatis (CT infection is one of the most common causes of reproductive tract diseases and infertility. CT-Hsp60 is synthesized during infection and is released in the bloodstream. As a consequence, immune cells will produce anti-CT-Hsp60 antibodies. Hsp60, a ubiquitous and evolutionarily conserved chaperonin, is normally sequestered inside the cell, particularly into mitochondria. However, upon cell stress, as well as during carcinogenesis, the chaperonin becomes exposed on the cell surface (sf-Hsp60 and/or is secreted from cells into the extracellular space and circulation. Reports in the literature on circulating Hsp and anti-Hsp antibodies are in many cases short on details about Hsp60 concentrations, and about the specificity spectra of the antibodies, their titers, and their true, direct, pathogenetic effects. Thus, more studies are still needed to obtain a definitive picture on these matters. Nevertheless, the information already available indicates that the concurrence of persistent CT infection and appearance of sf-Hsp60 can promote an autoimmune aggression towards stressed cells and the development of diseases such as autoimmune arthritis, multiple sclerosis, atherosclerosis, vasculitis, diabetes, and thyroiditis, among others. At the same time, immunocomplexes composed of anti-CT-Hsp60 antibodies and circulating Hsp60 (both CT and human may form deposits in several anatomical locations, e.g., at the glomerular basal membrane. The opposite side of the coin is that pre-tumor and tumor cells with sf-Hsp60 can be destroyed with participation of the anti-Hsp60 antibody, thus stopping cancer progression before it is even noticed by the patient or physician.

  10. The effect of curve sawing two-sided cants from small diameter hardwood sawlogs on lumber and pallet part yields

    Science.gov (United States)

    Peter Hamner; Marshall S. White; Philip A. Araman

    2006-01-01

    Curve sawing is a primary log breakdown process that incorporates gang-saw technology to allow two-sided cants from logs with sweep to be cut parallel to the log surface or log axis. Since curve-sawn logs with sweep are cut along the grain, the potential for producing high quality straight-grain lumber and cants increases, and strength, stiffness, and dimensional...

  11. An Evaluation of One-Sided and Two-Sided Communication Paradigms on Relaxed-Ordering Interconnect

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, Khaled Z. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hargrove, Paul H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Iancu, Costin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Yelick, Katherine [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-08-14

    The Cray Gemini interconnect hardware provides multiple transfer mechanisms and out-of-order message delivery to improve communication throughput. In this paper we quantify the performance of one-sided and two-sided communication paradigms with respect to: 1) the optimal available hardware transfer mechanism, 2) message ordering constraints, 3) per node and per core message concurrency. In addition to using Cray native communication APIs, we use UPC and MPI micro-benchmarks to capture one- and two-sided semantics respectively. Our results indicate that relaxing the message delivery order can improve performance up to 4.6x when compared with strict ordering. When hardware allows it, high-level one-sided programming models can already take advantage of message reordering. Enforcing the ordering semantics of two-sided communication comes with a performance penalty. Furthermore, we argue that exposing out-of-order delivery at the application level is required for the next-generation programming models. Any ordering constraints in the language specifications reduce communication performance for small messages and increase the number of active cores required for peak throughput.

  12. The analytical utility of thermally desorbed polydimethylsilicone membranes for in-vivo sampling of volatile organic compounds in and on human skin.

    Science.gov (United States)

    Riazanskaia, S; Blackburn, G; Harker, M; Taylor, D; Thomas, C L P

    2008-08-01

    A thermally-desorbed polydimethylsilicone (PDMS) membrane approach with analysis by gas chromatography-mass spectrometry has been developed and characterised, to enable the VOC arising in, and on skin, from glandular secretions, exogenous materials, products of perfusion from blood, and microbiological metabolites to be sampled in a single procedure. In-vitro studies using a series of volatile fatty acid standards indicated that the recovery efficiency of the technique increased with decreasing volatility; for example, the recovery of hexanoic acid was 3.3 times greater than that for 2-methylpropanoic acid. The relative standard deviation of the methodology decreased with decreasing volatility; RSD = 19% for 2-methylpropanoic acid and RSD = 7% for hexanoic acid. Sampled-mass vs. response relationships were modelled satisfactorily using linear regression analysis with regression coefficients in the range 0.95 to 0.998. In-vivo reproducibility was assessed though the analysis of the responses of 1-dodecane, 3,7-dimethyloct-1-ene, 2-propenoic acid, 2-ethylhexyl ester, 2-ethylhexan-1-ol, butanoic, 2-ethylhexylester, and junipen (1,4-methanoazulene, decahydro-4,8,8-trimethyl-9-methylene-); six compounds selected at random retention times from a GC-MS chromatographic VOC profile of human skin containing several hundred resolved and partially resolved compounds. Five samples were obtained simultaneously from the forearm of a healthy male participant. The in-vivo sample masses were estimated to be in the range 50 pg to 100 ng per sample with observed RSD falling between 15% and 32%; in line with a Horwitz trend. Increasing the sample time from 5 min to 120 min generally resulted in an enrichment of the VOC recovered, and for many VOC substantial increases in sensitivity (x7) were observed over this time range as the PDMS sampling-patch approached equilibrium with the underlying skin. Nevertheless, more volatile components, 2,4,6-trimethylcarbazole for instance, were

  13. Complexation induced phase separation: preparation of composite membranes with a nanometer thin dense skin loaded with metal ions

    KAUST Repository

    Villalobos Vazquez de la Parra, Luis Francisco

    2015-04-21

    We present the development of a facile phase-inversion method for forming asymmetric membranes with a precise high metal ion loading capacity in only the dense layer. The approach combines the use of macromolecule-metal intermolecular complexes to form the dense layer of asymmetric membranes with nonsolvent-induced phase separation to form the porous support. This allows the independent optimization of both the dense layer and porous support while maintaining the simplicity of a phase-inversion process. Moreover, it facilitates control over (i) the thickness of the dense layer throughout several orders of magnitude—from less than 15 nm to more than 6 μm, (ii) the type and amount of metal ions loaded in the dense layer, (iii) the morphology of the membrane surface, and (iv) the porosity and structure of the support. This simple and scalable process provides a new platform for building multifunctional membranes with a high loading of well-dispersed metal ions in the dense layer.

  14. Ultrastructural localization of the core protein of a basement membrane-specific chondroitin sulfate proteoglycan in adult rat skin

    DEFF Research Database (Denmark)

    McCarthy, K J; Horiguchi, Y; Couchman, J R

    1990-01-01

    Basement membranes are complex extracellular matrices present at epithelial/mesenchymal interfaces of tissues. The dermal-epidermal junction has been shown to contain numerous components, some of the most well known being laminin, types IV and VII collagens, heparan sulfate proteoglycan, fibronec...

  15. Complexation induced phase separation: preparation of composite membranes with a nanometer thin dense skin loaded with metal ions

    KAUST Repository

    Villalobos Vazquez de la Parra, Luis Francisco; Karunakaran, Madhavan; Peinemann, Klaus-Viktor

    2015-01-01

    We present the development of a facile phase-inversion method for forming asymmetric membranes with a precise high metal ion loading capacity in only the dense layer. The approach combines the use of macromolecule-metal intermolecular complexes to form the dense layer of asymmetric membranes with nonsolvent-induced phase separation to form the porous support. This allows the independent optimization of both the dense layer and porous support while maintaining the simplicity of a phase-inversion process. Moreover, it facilitates control over (i) the thickness of the dense layer throughout several orders of magnitude—from less than 15 nm to more than 6 μm, (ii) the type and amount of metal ions loaded in the dense layer, (iii) the morphology of the membrane surface, and (iv) the porosity and structure of the support. This simple and scalable process provides a new platform for building multifunctional membranes with a high loading of well-dispersed metal ions in the dense layer.

  16. Development of a membrane of poly (L-co-D,L lactic acid-co-trimethylene carbonate) with aloe vera: An alternative biomaterial designed to improve skin healing.

    Science.gov (United States)

    Komatsu, Daniel; Mistura, Daniel V; Motta, Adriana; Domingues, Juliana A; Hausen, Moema A; Duek, Eliana

    2017-09-01

    The search for new therapies and drugs that act as topical agents to relieve pain and control the infectious processes in burns always attracted interest in clinical trials. As an alternative to synthetic drugs, the use of natural extracts is useful in the development of new strategies and formulations for improving the life quality. The aim of this study was to develop a wound dressing using Poly(L-co-D,L lactic acid-co-TMC) (PLDLA-co-TMC) containing aloe vera (AV). This natural plant extract is known for its modulatory effects under healing process. The membrane of PLDLA-co-TMC+aloe vera was prepared at different concentrations of AV (5, 10, 15 and 50%). The FTIR showed no change in the PLDLA-co-TMC spectrum after AV addition, while the swelling test showed changes only in PLDLA-co-TMC+AV at 50%. The wettability measurements showed decrease in the contact angle in all samples after the AV addition in the polymer, while the AV release test showed that PLDLA-co-TMC+50%AV sample has higher AV release rate than the sample with other AV concentrations. The SEM analysis showed that AV was homogeneously distributed at 5% only. Tensile tests demonstrated an increase in the Young's modulus and a reduction in the elongation till rupture of the PLDLA-co-TMC after the addition of AV. Biocompatibility in vitro evaluation with fibroblast cells seeded in the membranes of PLDLA-co-TMC+AV showed that the cells were able to adhere, proliferate and maintain mitochondrial activity in all AV concentrations tested. Due to the known skin medicinal properties attributed to AV and the results here obtained, we suggest that after in vivo trials, the PLDLA-co-TMC+AV should be a promising biomaterial for application as a device for skin curative and healing agent.

  17. Rational Arithmetic Mathematica Functions to Evaluate the Two-Sided One Sample K-S Cumulative Sampling Distribution

    Directory of Open Access Journals (Sweden)

    J. Randall Brown

    2007-06-01

    Full Text Available One of the most widely used goodness-of-fit tests is the two-sided one sample Kolmogorov-Smirnov (K-S test which has been implemented by many computer statistical software packages. To calculate a two-sided p value (evaluate the cumulative sampling distribution, these packages use various methods including recursion formulae, limiting distributions, and approximations of unknown accuracy developed over thirty years ago. Based on an extensive literature search for the two-sided one sample K-S test, this paper identifies an exact formula for sample sizes up to 31, six recursion formulae, and one matrix formula that can be used to calculate a p value. To ensure accurate calculation by avoiding catastrophic cancelation and eliminating rounding error, each of these formulae is implemented in rational arithmetic. For the six recursion formulae and the matrix formula, computational experience for sample sizes up to 500 shows that computational times are increasing functions of both the sample size and the number of digits in the numerator and denominator integers of the rational number test statistic. The computational times of the seven formulae vary immensely but the Durbin recursion formula is almost always the fastest. Linear search is used to calculate the inverse of the cumulative sampling distribution (find the confidence interval half-width and tables of calculated half-widths are presented for sample sizes up to 500. Using calculated half-widths as input, computational times for the fastest formula, the Durbin recursion formula, are given for sample sizes up to two thousand.

  18. Two-sided messages for health risk prevention: the role of argument type, refutation, and issue ambivalence.

    Science.gov (United States)

    Cornelis, Erlinde; Cauberghe, Veroline; De Pelsmacker, Patrick

    2013-06-01

    Two experiments were conducted among adolescents in 2011 in urban parts of Belgium, Europe. The effectiveness of two-sided binge drinking and marijuana prevention messages was investigated in relation to argument type, refutation, and issue ambivalence. Study 1 (n = 373) serves as a baseline study for study 2 (n = 156). Data were collected through a printed questionnaire in classrooms in Flemish secondary schools. Analysis of variance (ANOVA) was used to analyze the data. Implications for health practitioners, as well as limitations and suggestions for further research are given.

  19. Multi-Criterion Two-Sided Matching of Public–Private Partnership Infrastructure Projects: Criteria and Methods

    Directory of Open Access Journals (Sweden)

    Ru Liang

    2018-04-01

    Full Text Available Two kinds of evaluative criteria are associated with Public–Private Partnership (PPP infrastructure projects, i.e., private evaluative criteria and public evaluative criteria. These evaluative criteria are inversely related, that is, the higher the public benefits; the lower the private surplus. To balance evaluative criteria in the Two-Sided Matching (TSM decision, this paper develops a quantitative matching decision model to select an optimal matching scheme for PPP infrastructure projects based on the Hesitant Fuzzy Set (HFS under unknown evaluative criterion weights. In the model, HFS is introduced to describe values of the evaluative criteria and multi-criterion information is fully considered given by groups. The optimal model is built and solved by maximizing the whole deviation of each criterion so that the evaluative criterion weights are determined objectively. Then, the match-degree of the two sides is calculated and a multi-objective optimization model is introduced to select an optimal matching scheme via a min-max approach. The results provide new insights and implications of the influence on evaluative criteria in the TSM decision.

  20. Lower Prevalence of Atopic Dermatitis and Allergic Sensitization among Children and Adolescents with a Two-Sided Migrant Background.

    Science.gov (United States)

    Ernst, Sinja Alexandra; Schmitz, Roma; Thamm, Michael; Ellert, Ute

    2016-02-26

    In industrialized countries atopic diseases have been reported to be less likely in children and adolescents with a migrant background compared to non-migrants. This paper aimed at both examining and comparing prevalence of asthma, allergic rhinoconjunctivitis and atopic dermatitis and allergic sensitization to specific IgE antibodies in children and adolescents with and without a migrant background. Using data of the population-based German Health Interview and Examination Survey for children and adolescents (KiGGS;n = 17,450; 0-17 years), lifetime and 12-month prevalence of atopic diseases and point prevalence of 20 common allergic sensitizations were investigated among migrants compared to non-migrants. Multiple regression models were used to estimate the association of atopic disease and allergic sensitization with migrant background. In multivariate analyses with substantial adjustment we found atopic dermatitis about one-third less often (OR 0.73, 0.57-0.93) in participants with a two-sided migrant background. Statistically significant associations between allergic sensitizations and a two-sided migrant background remained for birch (OR 0.73, 0.58-0.90), soybean (OR 0.72, 0.54-0.96), peanut (OR 0.69, 0.53-0.90), rice (OR 0.64, 0.48-0.87), potato (OR 0.64, 0.48-0.85), and horse dander (OR 0.58, 0.40-0.85). Environmental factors and living conditions might be responsible for the observed differences.

  1. A Reliable Methodology for Determining Seed Viability by Using Hyperspectral Data from Two Sides of Wheat Seeds.

    Science.gov (United States)

    Zhang, Tingting; Wei, Wensong; Zhao, Bin; Wang, Ranran; Li, Mingliu; Yang, Liming; Wang, Jianhua; Sun, Qun

    2018-03-08

    This study investigated the possibility of using visible and near-infrared (VIS/NIR) hyperspectral imaging techniques to discriminate viable and non-viable wheat seeds. Both sides of individual seeds were subjected to hyperspectral imaging (400-1000 nm) to acquire reflectance spectral data. Four spectral datasets, including the ventral groove side, reverse side, mean (the mean of two sides' spectra of every seed), and mixture datasets (two sides' spectra of every seed), were used to construct the models. Classification models, partial least squares discriminant analysis (PLS-DA), and support vector machines (SVM), coupled with some pre-processing methods and successive projections algorithm (SPA), were built for the identification of viable and non-viable seeds. Our results showed that the standard normal variate (SNV)-SPA-PLS-DA model had high classification accuracy for whole seeds (>85.2%) and for viable seeds (>89.5%), and that the prediction set was based on a mixed spectral dataset by only using 16 wavebands. After screening with this model, the final germination of the seed lot could be higher than 89.5%. Here, we develop a reliable methodology for predicting the viability of wheat seeds, showing that the VIS/NIR hyperspectral imaging is an accurate technique for the classification of viable and non-viable wheat seeds in a non-destructive manner.

  2. Two sides of one coin: massive hepatic necrosis and progenitor cell-mediated regeneration in acute liver failure

    Directory of Open Access Journals (Sweden)

    Honglei eWeng

    2015-06-01

    Full Text Available Massive hepatic necrosis is a key event underlying acute liver failure, a serious clinical syndrome with high mortality. Massive hepatic necrosis in acute liver failure has unique pathophysiological characteristics including extremely rapid parenchymal cell death and removal. On the other hand, massive necrosis rapidly induces the activation of liver progenitor cells, the so-called second pathway of liver regeneration. The final clinical outcome of acute liver failure depends on whether liver progenitor cell-mediated regeneration can efficiently restore parenchymal mass and function within a short time. This review summarizes the current knowledge regarding massive hepatic necrosis and liver progenitor cell-mediated regeneration in patients with acute liver failure, the two sides of one coin.

  3. Two sides of one coin: massive hepatic necrosis and progenitor cell-mediated regeneration in acute liver failure.

    Science.gov (United States)

    Weng, Hong-Lei; Cai, Xiaobo; Yuan, Xiaodong; Liebe, Roman; Dooley, Steven; Li, Hai; Wang, Tai-Ling

    2015-01-01

    Massive hepatic necrosis is a key event underlying acute liver failure, a serious clinical syndrome with high mortality. Massive hepatic necrosis in acute liver failure has unique pathophysiological characteristics including extremely rapid parenchymal cell death and removal. On the other hand, massive necrosis rapidly induces the activation of liver progenitor cells, the so-called "second pathway of liver regeneration." The final clinical outcome of acute liver failure depends on whether liver progenitor cell-mediated regeneration can efficiently restore parenchymal mass and function within a short time. This review summarizes the current knowledge regarding massive hepatic necrosis and liver progenitor cell-mediated regeneration in patients with acute liver failure, the two sides of one coin.

  4. Skin graft

    Science.gov (United States)

    Skin transplant; Skin autografting; FTSG; STSG; Split thickness skin graft; Full thickness skin graft ... donor site. Most people who are having a skin graft have a split-thickness skin graft. This takes ...

  5. Evasion and Immuno-Endocrine Regulation in Parasite Infection: Two Sides of the Same Coin in Chagas Disease?

    Science.gov (United States)

    Morrot, Alexandre; Villar, Silvina R; González, Florencia B; Pérez, Ana R

    2016-01-01

    Chagas disease is a serious illness caused by the protozoan parasite Trypanosoma cruzi. Nearly 30% of chronically infected people develop cardiac, digestive, or mixed alterations, suggesting a broad range of host-parasite interactions that finally impact upon chronic disease outcome. The ability of T. cruzi to persist and cause pathology seems to depend on diverse factors like T. cruzi strains, the infective load and the route of infection, presence of virulence factors, the parasite capacity to avoid protective immune response, the strength and type of host defense mechanisms and the genetic background of the host. The host-parasite interaction is subject to a constant neuro-endocrine regulation that is thought to influence the adaptive immune system, and as the infection proceeds it can lead to a broad range of outcomes, ranging from pathogen elimination to its continued persistence in the host. In this context, T. cruzi evasion strategies and host defense mechanisms can be envisioned as two sides of the same coin, influencing parasite persistence and different outcomes observed in Chagas disease. Understanding how T. cruzi evade host's innate and adaptive immune response will provide important clues to better dissect mechanisms underlying the pathophysiology of Chagas disease.

  6. VALUE-ADDED SERVICE INVESTING AND PRICING STRATEGIES FOR A TWO-SIDED PLATFORM UNDER INVESTING RESOURCE CONSTRAINT

    Institute of Scientific and Technical Information of China (English)

    Guowei Dou; Ping He

    2017-01-01

    Investing on value-added service (VAS) amplifies users' participation and platform profit.However,the investing resource is usually limited in practice.This paper investigates VAS investing and pricing strategies for a two-sided platform under investing resource constraint.We reveal that with VAS investment,Subsidizing can still be done to enlarge users' demand,even when the investing cost becomes higher.For optimal pricing strategies,the network effect will be the dominating determinant if the gap between two marginal cross-side benefits (i.e.the benefit that users obtain when each new user join the other side of the platform) is large.Interestingly,we show that with the increase of the marginal investing cost,users might either be priced higher or lower.If the marginal investing cost increases to a high level,and the gap between the two marginal cross-side benefits is large,lowering the access fee for users possessing the higher cross-side network effect does not necessarily compensate more profit loss caused by higher cost.Moreover,after VAS is developed,raising the access fee for those whose marginal investing benefit is large does not necessarily generate more profit as well.The opposite strategy further enlarges users' utility,and promotes the investment to benefit more users.

  7. Two sides of the same coin--an interview study of Swedish obstetricians' experiences using ultrasound in pregnancy management.

    Science.gov (United States)

    Åhman, Annika; Persson, Margareta; Edvardsson, Kristina; Lalos, Ann; Graner, Sophie; Small, Rhonda; Mogren, Ingrid

    2015-11-20

    The extended use of ultrasound that is seen in maternity care in most Western countries has not only affected obstetric care but also impacted on the conception of the fetus in relation to the pregnant woman. This situation has also raised concerns regarding the pregnant woman's reproductive freedom. The purpose of this study was to explore Swedish obstetricians' experiences and views on the role of obstetric ultrasound particularly in relation to clinical management of complicated pregnancy, and in relation to situations where the interests of maternal and fetal health conflict. A qualitative study design was applied, and data were collected in 2013 through interviews with 11 obstetricians recruited from five different obstetric clinics in Sweden. Data were analysed using qualitative content analysis. The theme that emerged in the analysis 'Two sides of the same coin' depicts the view of obstetric ultrasound as a very important tool in obstetric care while it also was experienced as having given rise to new and challenging issues in the management of pregnancy. This theme was built on three categories: I. Ultrasound is essential and also demanding; II. A woman's health interest is prioritised in theory, but not always in practice; and III. Ultrasound is rewarding but may also cause unwarranted anxiety. The widespread use of ultrasound in obstetric care has entailed new challenges for clinicians due to enhanced possibilities to diagnose and treat fetal conditions, which in turn might conflict with the health interests of the pregnant woman. There is a need for further ethical discussions regarding the obstetrician's position in management of situations where maternal and fetal health interests conflict. The continuing advances in the potential of ultrasound to impact on pregnancy management will also increase the need for adequate and appropriate information and counselling. Together with other health care professionals, obstetricians therefore need to develop

  8. Skin Diseases: Skin Health and Skin Diseases

    Science.gov (United States)

    Skip Navigation Bar Home Current Issue Past Issues Skin Diseases Skin Health and Skin Diseases Past Issues / Fall 2008 Table of Contents ... acne to wrinkles Did you know that your skin is the largest organ of your body? It ...

  9. Interpretation of the measurement of ions fluxes through a biological membrane with a cellular compartment: example of the movements of sodium through the skin of frogs; Interpretation de la mesure des flux d'ions a travers une membrane biologique comportant un ''compartiment'' cellulaire; exemple des mouvements de sodium a travers la peau de grenouille

    Energy Technology Data Exchange (ETDEWEB)

    Morel, F [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    Two-way ion fluxes which can be measured in vitro through a living epithelial membrane (such as frog skin) by the indicator method take place across the cells which behave like an intermediate ionic 'compartment'. Two membranes and four fluxes have thus to be considered. Measurements in vitro of the total sodium fluxes as a function of the sodium concentration in the medium in contact with the external face of the skin have been interpreted in this spirit. Making use of certain hypotheses, the permeability coefficients for sodium of the two cellular membranes, the four sodium fluxes, the intracellular sodium concentration and the membrane potentials have been calculated for each value of the sodium concentration in the external medium. (author) [French] Les flux ioniques bidirectionnels que l'on peut mesurer in vitro a travers une membrane epitheliale vivante (comme la peau de grenouille) a l'aide de la methode des indicateurs, s'effectuent a travers les cellules qui se comportent comme un 'compartiment' ionique intermediaire. On doit donc considerer deux membranes et quatre flux. Des mesures in vitro des flux totaux de sodium en fonction de la concentration du sodium dans le milieu baignant la face externe de la peau ont ete interpretees dans cette perspective. Moyennant certaines hypotheses, les coefficients de permeabilite pour le sodium des deux membranes cellulaires, les quatre flux de sodium ainsi que la concentration du sodium intracellulaire et les potentiels de membrane ont pu etre calcules pour chaque valeur de la concentration du sodium dans le milieu externe. (auteur)

  10. Plasmoacanthoma of oral cavity and plasma cell cheilitis: two sides of same disorder “oral plasma cell mucositis” ?

    Directory of Open Access Journals (Sweden)

    Gayatri Khatri

    2014-04-01

    Full Text Available Plasmoacanthoma and plasma cell cheilitis are rare disorders of obscure etiology characterized by a plasma cell infiltrate an 80-year-old woman presented with a verrucous, fleshy, skin colored plaque over lips, gingiva, and the palate and painful swallowing for over a period of 6 months. Histopathology of the lesion showed dense infiltrate of plasma cells. The lesions resolved completely after intralesional triamcinolone acetonide. Another 52-year-old male had progressively enlarging, erosive lesion over vermilion border of lower lip for 6months resembling actinic cheilitis. Histology was diagnostic of plasma cell cheilitis. Treatment with topical clobetasol propionate was effective. Plasma cell cheilitis and plasmoacanthoma perhaps represent a spectrum of oral ”plasma cell mucositis” with plasmoacanthoma being an advanced version of the former.

  11. No Way Out or Swallow the Bait of Two-Sided Exit Options in Negotiation: The Influence of Social Motives and Interpersonal Trust

    NARCIS (Netherlands)

    Giebels, Ellen; de Dreu, Carsten K.W.; van de Vliert, Evert

    2003-01-01

    In two negotiation experiments with business students we examined effects of the two-sided availability of alternative negotiators in combination with the parties’ social motive. Contrary to our expectation, prosocial negotiators rather than egoistic negotiators were sensitive to the presence of

  12. Your Skin

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Your Skin KidsHealth / For Kids / Your Skin What's in this ... body) are really dead skin cells. Bye-Bye Skin Cells These old cells are tough and strong, ...

  13. Roads may act as barriers to flying insects: species composition of bees and wasps differs on two sides of a large highway

    Directory of Open Access Journals (Sweden)

    Petter Andersson

    2017-07-01

    Full Text Available Roads may act as barriers to animal movements, but direct barrier effects on insects have rarely been studied. In this study we collected data on bees and wasps along two sides of a large road in Sweden using yellow pan traps. We then analyzed if the species composition differed between the two sides of the road; first for the whole community, and then only for the smallest species (which typically are poorer dispersers. As a complement, we analyzed if different vegetation variables differed between the two sides of the road, as this may also affect differences in species composition. Finally, we analyzed if species richness and abundance in general differed between the two sides and how these two response variables were explained by the vegetation variables. There was a significant difference in species composition between the eastern and the western side of the road when analyzing the whole community, and this relationship became even stronger when the largest species were excluded. The vegetation variables did not strongly differ between the two sides, and there was no difference in species richness and abundance of bees and wasps either. Abundance was, however, explained by the number of flowering plants in the surroundings of the trap. Even though using a rather limited data set, our results indicate that large roads may act as barriers on the movement of bees and wasps, especially for small species with poor dispersal ability. On the other hand, road verges may be important habitat for many species, which leads to a potential conflict that is important to consider in the planning of green infrastructure.

  14. Skin-safe photothermal therapy enabled by responsive release of acid-activated membrane-disruptive polymer from polydopamine nanoparticle upon very low laser irradiation.

    Science.gov (United States)

    Zhu, Rui; Gao, Feng; Piao, Ji-Gang; Yang, Lihua

    2017-07-25

    How to ablate tumor without damaging skin is a challenge for photothermal therapy. We, herein, report skin-safe photothermal cancer therapy provided by the responsive release of acid-activated hemolytic polymer (aHLP) from the photothermal polydopamine (PDA) nanoparticle upon irradiation at very low dosage. Upon skin-permissible irradiation (via an 850 nm laser irradiation at the power density of 0.4 W cm -2 ), the nanoparticle aHLP-PDA generates sufficient localized-heat to bring about mild hyperthermia treatment and consequently, responsively sheds off the aHLP polymer from its PDA nanocore; this leads to selective cytotoxicity to cancer cells under the acidic conditions of the extracellular microenvironment of tumor. As a result, our aHLP-PDA nanoparticle upon irradiation at a low dosage effectively inhibits tumor growth without damaging skin, as demonstrated using animal models. Effective in mitigating the otherwise inevitable skin damage in tumor photothermal therapy, the nanosystem reported herein offers an efficient pathway towards skin-safe photothermal therapy.

  15. Two Sides of the Same Coin? Analysis of the Web-Based Social Media with Regard to the Image of the Agri-Food Sector in Germany

    Directory of Open Access Journals (Sweden)

    Justus Boehm

    2010-10-01

    Full Text Available  Never before has food been as safe and secure as it is today, but simultaneously, society has become increasingly critical towards agricultural and food related issues. This two-sided development between society and agribusiness will be analyzed using Framing Theory. A quantitative semantic analysis was applied to evaluate the web-based social media in Germany. 50,931 web posts were collected covering 21 issues identified as relevant for the agri-food sector. The results show that all contentious issues are mainly framed in a two-sided way. The modern productivity-driven industry is judged as a negative development, trends returning to a more natural food production are seen as positive.

  16. Skin Conditions

    Science.gov (United States)

    Your skin is your body's largest organ. It covers and protects your body. Your skin Holds body fluids in, preventing dehydration Keeps harmful ... it Anything that irritates, clogs, or inflames your skin can cause symptoms such as redness, swelling, burning, ...

  17. Skin abscess

    Science.gov (United States)

    Abscess - skin; Cutaneous abscess; Subcutaneous abscess; MRSA - abscess; Staph infection - abscess ... Skin abscesses are common and affect people of all ages. They occur when an infection causes pus ...

  18. Microfabricated hydrogen sensitive membranes

    Energy Technology Data Exchange (ETDEWEB)

    Naddaf, A.; Kraetz, L. [Lehrstuhl fuer Thermische Verfahrenstechnik, Technische Universitaet Kaiserslautern (Germany); Detemple, P.; Schmitt, S.; Hessel, V. [Institut fuer Mikrotechnik Mainz GmbH, Mainz (Germany); Faqir, N. [University of Jordan, Amman (Jordan); Bart, H.J.

    2009-01-15

    Thin, defect-free palladium, palladium/copper and palladium/silver hydrogen absorbing membranes were microfabricated. A dual sputtering technique was used to deposit the palladium alloy membranes of only 1 {mu}m thickness on a nonporous silicon substrate. Advanced silicon etching (ASE) was applied on the backside to create a mechanically stable support structure for the thin films. Performance evaluation was carried out for different gases in a temperature range of 20 C to 298 C at a constant differential pressure of 110 kPa at the two sides of the membrane. The composite membranes show an excellent permeation rate of hydrogen, which appears to be 0.05 Pa m{sup 3} s{sup -1} and 0.01.10{sup -3} Pa m{sup 3} s{sup -1} at 20 C for the microfabricated 23 % silver and the 53 % copper composite membranes, respectively. The selectivity to hydrogen over a gas mixture containing, in addition to hydrogen, carbon monoxide, carbon dioxide and nitrogen was measured. The mass spectrometer did not detect any CO{sub 2} or CO, showing that the membrane is completely hydrogen selective. The microfabricated membranes exhibit both high mechanical strength (they easily withstand pressures up to 4 bar) and high thermal stability (up to 650 C). (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  19. Utilization of reconstructed cultured human skin models as an alternative skin for permeation studies of chemical compounds

    OpenAIRE

    Kano, Satoshi; 藤堂, 浩明; 杉江, 謙一; 藤本, 英哲; 中田, 圭一; 徳留, 嘉寛; 橋本, フミ惠; 杉林, 堅次

    2010-01-01

    Two reconstructed human skin models, EpiskinSM and EpiDermTM, have been approved as alternative membranes for skin corrosive/irritation experiments due to their close correlation with animal skin. Such reconstructed human skin models were evaluated as alternative membranes for skin permeation experiments. Seven drugs with different lipophilicities and almost the same molecular weight were used as test penetrants. Relationships were investigated between permeability coefficients (P values) of ...

  20. Photothermal Radiometry for Skin Research

    Directory of Open Access Journals (Sweden)

    Perry Xiao

    2016-02-01

    Full Text Available Photothermal radiometry is an infrared remote sensing technique that has been used for skin and skin appendages research, in the areas of skin hydration, hydration gradient, skin hydration depth profiling, skin thickness measurements, skin pigmentation measurements, effect of topically applied substances, transdermal drug delivery, moisture content of bio-materials, membrane permeation, and nail and hair measurements. Compared with other technologies, photothermal radiometry has the advantages of non-contact, non-destructive, quick to make a measurement (a few seconds, and being spectroscopic in nature. It is also colour blind, and can work on any arbitrary sample surfaces. It has a unique depth profiling capability on a sample surface (typically the top 20 µm, which makes it particularly suitable for skin measurements. In this paper, we present a review of the photothermal radiometry work carried out in our research group. We will first introduce the theoretical background, then illustrate its applications with experimental results.

  1. Membrane potentials and intracellular Cl- activity of toad skin epithelium in relation to activation and deactivation of the transepithelial Cl- conductance

    DEFF Research Database (Denmark)

    Willumsen, N J; Larsen, Erik Hviid

    1986-01-01

    M in skins from animals adapted to distilled water. Both Va and acCl were found to be positively correlated with Isc (r = 0.66 and r = 0.70, respectively). In eight epithelia from animals adapted to dry milieu/tap water Va and acCl were measured with KCl Ringer's on the outside during activation...... V was stepped back to 40 mV, Va instantaneously shifted to -67.8 +/- 3.9 mV while acCl and fRa remained constant during deactivation of GCl. Similar results were obtained in epithelia impaled from the serosal side. In 12 skins from animals adapted to either tap water or distilled water the density...... zero.(ABSTRACT TRUNCATED AT 400 WORDS)...

  2. Skin Cancer.

    Science.gov (United States)

    Linares, Miguel A; Zakaria, Alan; Nizran, Parminder

    2015-12-01

    Skin cancer accounts for most malignancies across the globe. They are primarily divided into melanoma and nonmelanoma skin malignancies. Nonmelanoma skin cancer includes basal cell carcinoma and squamous cell carcinoma. Fair skin and chronic ultraviolet B exposure are the most important risk factors. Primary prevention is achieved by avoiding sun exposure and tanning beds. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Skin tightening.

    Science.gov (United States)

    Woolery-Lloyd, Heather; Kammer, Jenna N

    2011-01-01

    Skin tightening describes the treatment of skin laxity via radiofrequency (RF), ultrasound, or light-based devices. Skin laxity on the face is manifested by progressive loss of skin elasticity, loosening of the connective tissue framework, and deepening of skin folds. This results in prominence of submandibular and submental tissues. Genetic factors (chronological aging) and extrinsic factors (ultraviolet radiation) both contribute to skin laxity. There are many RF, ultrasound, and light-based devices directed at treating skin laxity. All of these devices target and heat the dermis to induce collagen contraction. Heating of the dermis causes collagen denaturation and immediate collagen contraction in addition to long-term collagen remodeling. Via RF, light, or ultrasound, these skin tightening devices deliver heat to the dermis to create new collagen and induce skin tightening. This chapter will provide an overview of the various skin tightening devices. Copyright © 2011 S. Karger AG, Basel.

  4. Self-tuning wireless power transmission scheme based on on-line scattering parameters measurement and two-side power matching.

    Science.gov (United States)

    Luo, Yanting; Yang, Yongmin; Chen, Zhongsheng

    2014-04-10

    Sub-resonances often happen in wireless power transmission (WPT) systems using coupled magnetic resonances (CMR) due to environmental changes, coil movements or component degradations, which is a serious challenge for high efficiency power transmission. Thus self-tuning is very significant to keep WPT systems following strongly magnetic resonant conditions in practice. Traditional coupled-mode ways is difficult to solve this problem. In this paper a two-port power wave model is presented, where power matching and the overall systemic power transmission efficiency are firstly defined by scattering (S) parameters. Then we propose a novel self-tuning scheme based on on-line S parameters measurements and two-side power matching. Experimental results testify the feasibility of the proposed method. These findings suggest that the proposed method is much potential to develop strongly self-adaptive WPT systems with CMR.

  5. A comparative study of mixed convection and its effect on partially active thermal zones in a two sided lid-driven cavity filled with nanofluid

    Directory of Open Access Journals (Sweden)

    Sumit Malik

    2016-09-01

    Full Text Available In the present study, a two sided lid-driven mixed convection nanofluid flow with discrete heat sources have been numerically investigated. A two dimensional computational visualization technique is used to study the flow behavior using four different cases; depending on the direction of moving vertical walls with fixed upper and lower walls. Two discrete heat sources of equal lengths are taken on the lower wall and the rest of it is kept insulated. The other walls are kept at constant low temperature. The effect of flow governing parameters such as Reynolds number 1⩽Re⩽100, Richardson number 0.1⩽Ri⩽10 and solid volume fraction 0.0⩽ϕ⩽0.2 with Prandtl number Pr=6.2 is studied to understand the fluid flow pattern and the heat transfer effect using isotherms and average Nusselt number.

  6. Repeated noxious stimulation of the skin enhances cutaneous pain perception of migraine patients in-between attacks: clinical evidence for continuous sub-threshold increase in membrane excitability of central trigeminovascular neurons.

    Science.gov (United States)

    Weissman-Fogel, Irit; Sprecher, Elliot; Granovsky, Yelena; Yarnitsky, David

    2003-08-01

    Recent clinical studies showed that acute migraine attacks are accompanied by increased periorbital and bodily skin sensitivity to touch, heat and cold. Parallel pre-clinical studies showed that the underlying mechanism is sensitization of primary nociceptors and central trigeminovascular neurons. The present study investigates the sensory state of neuronal pathways that mediate skin pain sensation in migraine patients in between attacks. The assessments of sensory perception included (a) mechanical and thermal pain thresholds of the periorbital area, electrical pain threshold of forearm skin, (b) pain scores to phasic supra-threshold stimuli in the same modalities and areas as above, and (c) temporal summation of pain induced by applying noxious tonic heat pain and brief trains of noxious mechanical and electrical pulses to the above skin areas. Thirty-four pain-free migraine patients and 28 age- and gender-matched controls were studied. Patients did not differ from controls in their pain thresholds for heat (44+/-2.6 vs. 44.6+/-1.9 degrees C), and electrical (4.8+/-1.6 vs. 4.3+/-1.6 mA) stimulation, and in their pain scores for supra-threshold phasic stimuli for all modalities. They did, however, differ in their pain threshold for mechanical stimulation, just by one von Frey filament (P=0.01) and in their pain scores of the temporal summation tests. Increased summation of pain was found in migraineurs for repeated mechanical stimuli (delta visual analog scale (VAS) +2.32+/-0.73 in patients vs. +0.16+/-0.83 in controls, P=0.05) and repeated electrical stimuli (delta VAS +3.83+/-1.91 vs -3.79+/-2.31, P=0.01). Increased summation corresponded with more severe clinical parameters of migraine and tended to depend on interval since last migraine attack. The absence of clinically or overt laboratory expressed allodynia suggests that pain pathways are not sensitized in the pain-free migraine patients. Nevertheless, the increased temporal summation, and the slight

  7. Skin Complications

    Science.gov (United States)

    ... Text Size: A A A Listen En Español Skin Complications Diabetes can affect every part of the ... lipoidica diabeticorum, diabetic blisters, and eruptive xanthomatosis. General Skin Conditions Bacterial Infections Several kinds of bacterial infections ...

  8. Cryotherapy - skin

    Science.gov (United States)

    Cryosurgery - skin; Warts - freezing; Warts - cryotherapy; Actinic keratosis - cryotherapy; Solar keratosis - cryotherapy ... may be used to: Remove warts Destroy precancerous skin lesions (actinic keratoses or solar keratoses) In rare ...

  9. Skin Cancer

    Science.gov (United States)

    Skin cancer is the most common form of cancer in the United States. The two most common types ... face, neck, hands, and arms. Another type of skin cancer, melanoma, is more dangerous but less common. Anyone ...

  10. Sagging Skin

    Science.gov (United States)

    ... turkey neck,” this occurs as skin loses its elasticity and in cases where individuals have lost a ... technique or procedure is appropriate for my skin type? Did the doctor show me before-and-after ...

  11. Skin Biopsy

    Science.gov (United States)

    ... Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & Behavior School & Family Life First Aid & Safety Doctors & ... like these: skin rashes or conditions, such as eczema or psoriasis skin infections, such as staph diseases, ...

  12. Skin Graft

    OpenAIRE

    Shimizu, Ruka; Kishi, Kazuo

    2012-01-01

    Skin graft is one of the most indispensable techniques in plastic surgery and dermatology. Skin grafts are used in a variety of clinical situations, such as traumatic wounds, defects after oncologic resection, burn reconstruction, scar contracture release, congenital skin deficiencies, hair restoration, vitiligo, and nipple-areola reconstruction. Skin grafts are generally avoided in the management of more complex wounds. Conditions with deep spaces and exposed bones normally require the use o...

  13. Skin Aging

    Science.gov (United States)

    Your skin changes as you age. You might notice wrinkles, age spots and dryness. Your skin also becomes thinner and loses fat, making it ... heal, too. Sunlight is a major cause of skin aging. You can protect yourself by staying out ...

  14. Two Sides of the Same Coin: The Positive and Negative Impact of Spiritual Religious Coping on Quality of Life and Depression in Dialysis Patients.

    Science.gov (United States)

    Vitorino, Luciano Magalhães; Soares, Renata de Castro E Santos; Santos, Ana Eliza Oliveira; Lucchetti, Alessandra Lamas Granero; Cruz, Jonas Preposi; Cortez, Paulo José Oliveira; Lucchetti, Giancarlo

    2017-08-01

    Studies have shown that spiritual/religious beliefs are associated with mental health and health-related quality of life (HRQoL). However, few studies evaluated how spiritual/religious coping (SRC) could affect hemodialysis patients. The present study investigated the role of SRC behaviors on HRQoL and depressive symptoms in hemodialysis patients. This was cross-sectional study with 184 patients. Patients completed the Beck Depression Inventory, Brief SRC Scale, Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), and a Sociodemographic and Health Characterization Questionnaire. From 218 patients, 184 (84.4%) were included (53.8% male with a median age of 55.9 years). Negative SRC, but not positive SRC, was associated with depressive symptoms. Positive SRC presented significant effects in SF-36 pain and physical and social functioning. On the other hand, negative SRC exhibited significant effects in SF-36 role emotional, energy/fatigue, pain, and physical functioning. SRC influences the mental health and HRQoL in Brazilian hemodialysis patients in two distinct ways. If used positively, it may have positive outcomes. However, if used negatively, it may lead to dysfunctional consequences such as greater depressive symptomatology and affect HRQoL. Health professionals must be aware of these "two sides of the same coin."

  15. Ulva and Enteromorpha (Ulvaceae, Chlorophyta) from two sides of the Yellow Sea: analysis of nuclear rDNA ITS and plastid rbcL sequence data

    Science.gov (United States)

    Wang, Jinfeng; Li, Nan; Jiang, Peng; Boo, Sung Min; Lee, Wook Jae; Cui, Yulin; Lin, Hanzhi; Zhao, Jin; Liu, Zhengyi; Qin, Song

    2010-07-01

    Ulvacean green seaweeds are common worldwide; they formed massive green tides in the Yellow Sea in recent years, which caused marine ecological problems as well as a social issue. We investigated two major genera of the Ulvaceae, Ulva and Enteromorpha, and collected the plastid rbcL and nuclear ITS sequences of specimens of the genera in two sides of the Yellow Sea and analyzed them. Phylogenetic trees of rbcL data show the occurrence of five species of Enteromorpha ( E. compressa, E. flexuosa, E. intestinalis, E. linza and E. prolifera) and three species of Ulva ( U. pertusa, U. rigida and U. ohnoi). However, we found U. ohnoi, which is known as a subtropical to tropical species, at two sites on Jeju Island, Korea. Four ribotypes in partial sequences of 5.8S rDNA and ITS2 from E. compressa were also found. Ribotype network analysis revealed that the common ribotype, occurring in China, Korea and Europe, is connected with ribotypes from Europe and China/Japan. Although samples of the same species were collected from both sides of the Yellow Sea, intraspecific genetic polymorphism of each species was low among samples collected worldwide.

  16. Dry Skin Relief

    Science.gov (United States)

    ... on a budget Skin care products Skin care secrets Skin lighteners Skin of color Summer skin problems ... condition, such as eczema. Additional related information Dermatologists' top tips for relieving dry skin FIND A DERMATOLOGIST ...

  17. Skin cancer

    International Nuclear Information System (INIS)

    Yamada, Michiko

    1992-01-01

    This chapter reviews the development of skin cancer associated with radiation, focusing on the knowledge of A-bomb radiation-induced skin cancer. Since the discovery of X radiation in 1895, acute and chronic radiation dermatitis has been the first matter of concern. Then, in 1902, skin cancer found among radiological personnel has posed a social problem. In earlier study determining the relationship between skin cancer and A-bomb radiation, there is no increase in the incidence of either skin cancer or precancerous condition during the first 20 years after A-bombing. More recent studies have showed that there is a significant correlation between the incidence of skin cancer and distance from the hypocenter; and the incidence of skin cancer is found to be remarkably increased since 1975 in the group exposed at ≤2,000 m. Excess relative risk is 2.2 at one Gy dose. The incidence of skin cancer is also found to be extremely increased with aging. Relative risk is high in younger A-bomb survivors at the time of exposure. Histologically, basal cell carcinoma is more senstitive to ionizing radiation than squamous cell carcinoma. (N.K.)

  18. Effectiveness of two-sided UV-C treatments in inhibiting natural microflora and extending the shelf-life of minimally processed 'Red Oak Leaf' lettuce.

    Science.gov (United States)

    Allende, Ana; McEvoy, James L; Luo, Yaguang; Artes, Francisco; Wang, Chien Y

    2006-05-01

    The use of UV-C radiation treatments to inhibit the microbial growth and extend the shelf-life of minimally processed 'Red Oak Leaf' lettuce was investigated. Initially, UV-C resistance of 20 bacterial strains from different genera often associated with fresh produce (Enterobacter, Erwinia, Escherichia, Leuconostoc, Pantoea, Pseudomonas, Rahnela, Salmonella, Serratia and Yersinia) were tested in vitro. Most of the bacterial strains were inhibited with the minimum dose (30 J m(-2)). Erwinia carotovora, Leuconostoc carnosum, Salmonella typhimurium, and Yersinia aldovae were the most resistant strains requiring a UV-C dose of 85 J m(-2) to completely inhibit growth. An in vivo study consisted of treating minimally processed 'Red Oak Leaf' lettuce (Lactuca sativa) with UV-C at three radiation doses (1.18, 2.37 and 7.11 kJ m(-2)) on each side of the leaves and storing the product under passive MAP conditions at 5 degrees C for up to 10 days. The gas composition inside packages varied significantly among the treatments, with CO2 concentrations positively and O2 concentrations negatively correlating with the radiation dose. All the radiation doses were effective in reducing the natural microflora of the product, although the highest doses showed the greatest microbial inhibitions. Taking into account the microbial limit set by Spanish legislation [Boletín Oficial del Estado (BOE), 2001. Normas de higiene para la elaboración, distribución y comercio de comidas preparadas, Madrid, Spain, Real Decreto 3484/2000, pp. 1435-1441], all UV-C treatments extended the shelf-life of the product. However, the 7.11 kJ m(-2) dose induced tissue softening and browning after 7 days of storage at 5 degrees C. Therefore, the use of two sided UV-C radiation, at the proper dose, is effective in reducing the natural microflora and extending the shelf-life of minimally processed 'Red Oak Leaf' lettuce.

  19. Chloride channels in toad skin

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Rasmussen, B E

    1982-01-01

    A study of the voltage and time dependence of a transepithelial Cl- current in toad skin (Bufo bufo) by the voltage-clamp method leads to the conclusion that potential has a dual role for Cl- transport. One is to control the permeability of an apical membrane Cl-pathway, the other is to drive Cl-...

  20. Membrane dynamics

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    Current topics include membrane-protein interactions with regard to membrane deformation or curvature sensing by BAR domains. Also, we study the dynamics of membrane tubes of both cells and simple model membrane tubes. Finally, we study membrane phase behavior which has important implications...... for the lateral organization of membranes as wells as for physical properties like bending, permeability and elasticity...

  1. Skin Dictionary

    Science.gov (United States)

    ... Registration General information Housing & travel Education Exhibit hall Mobile app 2019 Annual Meeting Derm Exam Prep Course ... SkinPAC State societies Scope of practice Truth in advertising NP/PA laws Action center Public and patients ...

  2. Hyperelastic skin

    Science.gov (United States)

    ... is most often seen in people who have Ehlers-Danlos syndrome. People with this disorder have very elastic skin. ... any member of your family been diagnosed with Ehlers-Danlos syndrome? What other symptoms are present? Genetic counseling may ...

  3. Skin Cancer

    Science.gov (United States)

    ... sunlamps. There are 2 types of UV rays: UVA rays (long-wave) – UVA rays penetrate clouds and glass. They penetrate the ... to cancer. But studies have shown that both UVA and UVB damage the skin and can cause ...

  4. Skin Cancer Screening

    Science.gov (United States)

    ... Genetics of Skin Cancer Skin Cancer Screening Research Skin Cancer Screening (PDQ®)–Patient Version What is screening? ... These are called diagnostic tests . General Information About Skin Cancer Key Points Skin cancer is a disease ...

  5. The isolated perfused human skin flap model: A missing link in skin penetration studies?

    Science.gov (United States)

    Ternullo, Selenia; de Weerd, Louis; Flaten, Gøril Eide; Holsæter, Ann Mari; Škalko-Basnet, Nataša

    2017-01-01

    Development of effective (trans)dermal drug delivery systems requires reliable skin models to evaluate skin drug penetration. The isolated perfused human skin flap remains metabolically active tissue for up to 6h during in vitro perfusion. We introduce the isolated perfused human skin flap as a close-to-in vivo skin penetration model. To validate the model's ability to evaluate skin drug penetration the solutions of a hydrophilic (calcein) and a lipophilic (rhodamine) fluorescence marker were applied. The skin flaps were perfused with modified Krebs-Henseleit buffer (pH7.4). Infrared technology was used to monitor perfusion and to select a well-perfused skin area for administration of the markers. Flap perfusion and physiological parameters were maintained constant during the 6h experiments and the amount of markers in the perfusate was determined. Calcein was detected in the perfusate, whereas rhodamine was not detectable. Confocal images of skin cross-sections shoved that calcein was uniformly distributed through the skin, whereas rhodamine accumulated in the stratum corneum. For comparison, the penetration of both markers was evaluated on ex vivo human skin, pig skin and cellophane membrane. The proposed perfused flap model enabled us to distinguish between the penetrations of the two markers and could be a promising close-to-in vivo tool in skin penetration studies and optimization of formulations destined for skin administration. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Simulation of stretch forming with intermediate heat treatments of aircraft skins - A physically based modeling approach

    NARCIS (Netherlands)

    Kurukuri, S.; Miroux, Alexis; Wisselink, H.H.; van den Boogaard, Antonius H.

    2011-01-01

    In the aerospace industry stretch forming is often used to produce skin parts. During stretch forming a sheet is clamped at two sides and stretched over a die, such that the sheet gets the shape of the die. However for complex shapes it is necessary to use expensive intermediate heat-treatments in

  7. Skin decontamination

    International Nuclear Information System (INIS)

    Moehrle, G.

    1975-01-01

    A general survey of skin decontamination is given. The success of every decontamination treatments depends mainly on the speed, but also on the care, with which the action is taken. The best way to remove the skin contaminants is thorough washing under lukewarm running water with mild soap and a soft brush. This washing is to be repeated several times for a period of several minutes. If results are not satisfactory, light duty detergents and wetting agents available commercially may also be used. Some solutions which have proved useful are mentioned. The decontamination solutions are best used in the order given. When one has no satisfactory decontamination effect, the next one is to be used. If necessary, these agents must be used several times in the stated order as long as this does not involve too much strain for the skin. All the decontamination measures mentioned refer, of course, to intact healthy skin. After decontamination has been completed, the skin should be treated with a protective cream

  8. Minimum-error quantum distinguishability bounds from matrix monotone functions: A comment on 'Two-sided estimates of minimum-error distinguishability of mixed quantum states via generalized Holevo-Curlander bounds' [J. Math. Phys. 50, 032106 (2009)

    International Nuclear Information System (INIS)

    Tyson, Jon

    2009-01-01

    Matrix monotonicity is used to obtain upper bounds on minimum-error distinguishability of arbitrary ensembles of mixed quantum states. This generalizes one direction of a two-sided bound recently obtained by the author [J. Tyson, J. Math. Phys. 50, 032106 (2009)]. It is shown that the previously obtained special case has unique properties.

  9. Nanostructured Polysulfone-Based Block Copolymer Membranes

    KAUST Repository

    Xie, Yihui

    2016-01-01

    polycondensation and reversible addition-fragmentation chain-transfer polymerization. The obtained membrane has a highly porous interconnected skin layer composed of elongated micelles with a flower-like arrangement, on top of the graded finger-like macrovoids

  10. Squamous cell skin cancer

    Science.gov (United States)

    ... that reflect light more, such as water, sand, concrete, and areas that are painted white. The higher ... - skin - squamous cell; Skin cancer - squamous cell; Nonmelanoma skin cancer - squamous ...

  11. Membrane fusion

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    At Stanford University, Boxer lab, I worked on membrane fusion of small unilamellar lipid vesicles to flat membranes tethered to glass surfaces. This geometry closely resembles biological systems in which liposomes fuse to plasma membranes. The fusion mechanism was studied using DNA zippering...... between complementary strands linked to the two apposing membranes closely mimicking the zippering mechanism of SNARE fusion complexes....

  12. Skin Pigmentation Disorders

    Science.gov (United States)

    Pigmentation means coloring. Skin pigmentation disorders affect the color of your skin. Your skin gets its color from a pigment called melanin. Special cells in the skin make melanin. When these cells become damaged or ...

  13. Skin Cancer Foundation

    Science.gov (United States)

    ... Host a Fundraising Event | About Us | Store The Skin Cancer Foundation The Skin Cancer Foundation is the ... Handbook A "Sunscreen Gene"? Skin Cancer Facts & Statistics Skin Cancer Treatment Glossary Information on medications and procedures ...

  14. Skin Cancer Treatment

    Science.gov (United States)

    ... Unusual Cancers of Childhood Treatment Genetics of Skin Cancer Skin color and being exposed to sunlight can increase ... is based on the type of nonmelanoma skin cancer or other skin condition diagnosed: Basal cell carcinoma Enlarge Basal cell ...

  15. Stages of Skin Cancer

    Science.gov (United States)

    ... Unusual Cancers of Childhood Treatment Genetics of Skin Cancer Skin color and being exposed to sunlight can increase ... is based on the type of nonmelanoma skin cancer or other skin condition diagnosed: Basal cell carcinoma Enlarge Basal cell ...

  16. Cutaneous skin tag

    Science.gov (United States)

    Skin tag; Acrochordon; Fibroepithelial polyp ... have diabetes. They are thought to occur from skin rubbing against skin. ... The tag sticks out of the skin and may have a short, narrow stalk connecting it to the surface of the skin. Some skin tags are as long as ...

  17. 单面与双面信息广告重复效应的实证研究%An Empirical Study on One-sided VS Two-sided Advertising's Repetition Effect

    Institute of Scientific and Technical Information of China (English)

    代祺; 梁樑

    2011-01-01

    By introducing the variable of business ethics perception and integrating Optimal Arousal Theory, Processing Fluency Model, Attribution Theory and Two Factor Theory, the study compares the repetition effects differences between one and two-sided advertisements. Using inter-group experiment design, the results suggest that two-sided advertisements are processed less fluently than one-sided ones, but the percentage of accurate recall and advertisement response are higher than its counterpart. The repetition effects are inverted U shape for one-side advertisements and monotonic increase for two-sided advertisements. Thus, the wearing out effects of two-sided advertisements is delayed. The diversity in perception of business ethics play important role in determining this differences.%通过引入企业道德感知变量,并在整合最优唤醒理论、加工流畅模型、归因理论和两因素理论的基础上,深入剖析了单、双面信息广告重复效应的差异.研究结果表明:双面信息广告比单面信息广告加工更困难,但消费者对其广告正确回忆率更高,广告反应也更积极.单面信息广告的重复效应呈现先增后减的倒U趋势,而双面信息广告的重复效应呈单调递增趋势,疲劳效应延迟出现.消费者对企业道德感知的差异在很大程度上决定了单、双面信息广告重复效应的差异.

  18. Membrane Biophysics

    CERN Document Server

    Ashrafuzzaman, Mohammad

    2013-01-01

    Physics, mathematics and chemistry all play a vital role in understanding the true nature and functioning of biological membranes, key elements of living processes. Besides simple spectroscopic observations and electrical measurements of membranes we address in this book the phenomena of coexistence and independent existence of different membrane components using various theoretical approaches. This treatment will be helpful for readers who want to understand biological processes by applying both simple observations and fundamental scientific analysis. It provides a deep understanding of the causes and effects of processes inside membranes, and will thus eventually open new doors for high-level pharmaceutical approaches towards fighting membrane- and cell-related diseases.

  19. Anyone Can Get Skin Cancer

    Science.gov (United States)

    ... of Skin Cancer Skin Cancer Screening Research Anyone Can Get Skin Cancer Order the free Anyone Can ... rarely, younger children can develop skin cancer. How can people with dark skin get skin cancer? Although ...

  20. Skin dose assessment in routine personnel beta/gamma dosimetry

    International Nuclear Information System (INIS)

    Christensen, P.

    1980-01-01

    Three alternative methods are outlined by which substantial improvements of the capabilities of existing routine monitoring systems for skin dose assessment can be obtained. The introduction of a supplementary skin dosemeter may be an attractive method for systems with badges that have a capability for an additional dosemeter already built-in. The two-side reading method has limited possibilities because of reduced accuracy for mixed radiation and technical difficulties in using it for TLD systems with planchet heating. The use of a boron diffused LiF layer for skin dose assessment seems to be most attractive method since the only modification needed here is replacement of a dosemeter. However the study of this method is so far only in a preliminary stage and further investigations are needed. (U.K.)

  1. p63 in skin development and ectodermal dysplasias

    Science.gov (United States)

    Koster, Maranke I.

    2010-01-01

    The transcription factor p63 is critically important for skin development and maintenance. Processes that require p63 include epidermal lineage commitment, epidermal differentiation, cell adhesion, and basement membrane formation. Not surprisingly, alterations in the p63 pathway underlie a subset of ectodermal dysplasias, developmental syndromes in which the skin and skin appendages do not develop normally. This review summarizes the current understanding of the role of p63 in normal development and ectodermal dysplasias. PMID:20445549

  2. Abnormally dark or light skin

    Science.gov (United States)

    Hyperpigmentation; Hypopigmentation; Skin - abnormally light or dark ... Normal skin contains cells called melanocytes. These cells produce melanin , the substance that gives skin its color. Skin with ...

  3. Mathematical Model to Predict Skin Concentration after Topical Application of Drugs

    Directory of Open Access Journals (Sweden)

    Hiroaki Todo

    2013-12-01

    Full Text Available Skin permeation experiments have been broadly done since 1970s to 1980s as an evaluation method for transdermal drug delivery systems. In topically applied drug and cosmetic formulations, skin concentration of chemical compounds is more important than their skin permeations, because primary target site of the chemical compounds is skin surface or skin tissues. Furthermore, the direct pharmacological reaction of a metabolically stable drug that binds with specific receptors of known expression levels in an organ can be determined by Hill’s equation. Nevertheless, little investigation was carried out on the test method of skin concentration after topically application of chemical compounds. Recently we investigated an estimating method of skin concentration of the chemical compounds from their skin permeation profiles. In the study, we took care of “3Rs” issues for animal experiments. We have proposed an equation which was capable to estimate animal skin concentration from permeation profile through the artificial membrane (silicone membrane and animal skin. This new approach may allow the skin concentration of a drug to be predicted using Fick’s second law of diffusion. The silicone membrane was found to be useful as an alternative membrane to animal skin for predicting skin concentration of chemical compounds, because an extremely excellent extrapolation to animal skin concentration was attained by calculation using the silicone membrane permeation data. In this chapter, we aimed to establish an accurate and convenient method for predicting the concentration profiles of drugs in the skin based on the skin permeation parameters of topically active drugs derived from steady-state skin permeation experiments.

  4. Skin color - patchy

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003224.htm Skin color - patchy To use the sharing features on this page, please enable JavaScript. Patchy skin color is areas where the skin color is irregular. ...

  5. Histoplasma skin test

    Science.gov (United States)

    Histoplasmosis skin test ... health care provider cleans an area of your skin, usually the forearm. An allergen is injected just below the cleaned skin surface. An allergen is a substance that causes ...

  6. Skin Condition Finder

    Science.gov (United States)

    ... SKIN CONDITIONS HEALTH TOPICS FOR PROFESSIONALS Rash and Skin Condition Finder 1 Select Age Group Infant Child ... Toe Toe Webspace Toe Nail CLOSE About the Skin Condition Finder Have a health question or concern? ...

  7. Skin Complications of IBD

    Science.gov (United States)

    ... Home > Resources > Skin Complications of IBD Go Back Skin Complications of IBD Email Print + Share After arthritis, ... about 5% of people with inflammatory bowel disease. SKIN DISORDERS COMMONLY SEEN IN IBD ERHTHEMA NODOSUM The ...

  8. Skin Peeling Syndrome

    Directory of Open Access Journals (Sweden)

    Sharma Rajeev

    2000-01-01

    Full Text Available Peeling of the skin is an uncommonly encountered disorder. Occurrence of vesicles and bullae in peeling skin syndrome is very rare. We report a case of idiopathic peeling skin syndrome with vesicular lesions.

  9. Basolateral Cl- channels in the larval bullfrog skin epithelium

    DEFF Research Database (Denmark)

    Hillyard, Stanley D.; Rios, K.; Larsen, Erik Hviid

    2002-01-01

    The addition of 150 U/ml nystatin to the mucosal surface of isolated skin from larval bullfrogs increases apical membrane permeability and allows a voltage clamp to be applied to the basolateral membrane. With identical Ringer's solutions bathing either side of the tissue the short-circuit curren...

  10. Two Sides of the Same Coin: Leadership.

    Science.gov (United States)

    Berg, Steven; Burns, James MacGregor; McKay, Ritchie

    2002-01-01

    This article presents a transcript of Steven Berg's interviews with James MacGregor Burns and Ritchie McKay regarding leadership. James Burns is a senior fellow in the Jepson School of Leadership Studies at the University of Richmond, Virginia. Ritchie McKay is Head Coach of the men's basketball team at University of New Mexico. Steven Berg is an…

  11. The two sides of silicon detectors

    International Nuclear Information System (INIS)

    Devine, S.R.

    2001-10-01

    Results are presented on in situ irradiation of silicon detector's at cryogenic temperature. The results show that irradiation at cryogenic temperatures does not detrimentally effect a silicon detectors performance when compared to its irradiation at room temperature. Operation of silicon devices at cryogenic temperatures offers the advantage of reducing radiation-induced leakage current to levels of a few pA, while at 130K the Lazarus Effect plays an important role i.e. minimum voltage required for full depletion. Performing voltage scans on a 'standard' silicon pad detector pre- and post annealing, the charge collection efficiency was found to be 60% at 200V and 95% at 200V respectively. Time dependence measurements are presented, showing that for a dose of 6.5x10 14 p/cm 2 (450GeV protons) the time dependence of the charge collection efficiency is negligible. However, for higher doses, 1.2x10 15 p/cm 2 , the charge collection efficiency drops from an initial measured value of 67% to a stable value of 58% over a period of 15 minutes for reversed biased diodes. An analysis of the 'double junction' effect is also presented. A comparison between the Transient Current Technique and an X-ray technique is presented. The double junction has been observed in p + /n/n + silicon detectors after irradiation beyond 'type inversion', corresponding to a fluence equivalent to ∼3x10 13 cm -2 1MeV neutrons, producing p + /p/n + and essentially two p-n junctions within one device. With increasing bias voltage, as the electric field is extending into the detector bulk from opposite sides of the silicon detector, there are two distinct depletion regions that collect charge signal independently. Summing the signal charge from the two regions, one is able to reconstruct the initial energy of the incident particle. From Transient Current measurements it is apparent that E-field manipulation is possible by excess carrier injection, enabling a high enough E-field to extend across the width of the detector, allowing for efficient charge collection. (author)

  12. The Two Sides of the Representative Coin

    Directory of Open Access Journals (Sweden)

    Keith Sutherland

    2011-12-01

    Full Text Available In Federalist 10 James Madison drew a functional distinction between “parties” (advocates for factional interests and “judgment” (decision-making for the public good and warned of the corrupting effect of combining both functions in a “single body of men.” This paper argues that one way of overcoming “Madisonian corruption” would be by restricting political parties to an advocacy role, reserving the judgment function to an allotted (randomly-selected microcosm of the whole citizenry, who would determine the outcome of parliamentary debates by secret ballot—a division of labour suggested by James Fishkin’s experiments in deliberative polling. The paper then defends this radical constitutional proposal against Bernard Manin’s (1997 claim that an allotted microcosm could not possibly fulfil the “consent” requirement of Natural Right theory. Not only does the proposal challenge Manin’s thesis, but a 28th Amendment implementing it would finally reconcile the competing visions that have bedevilled representative democracy since the Constitutional Convention of 1787.

  13. THE TWO SIDES OF MONEY LAUNDERING

    Directory of Open Access Journals (Sweden)

    Corina – Maria ENE

    2014-12-01

    Full Text Available The mainly goal of money laundering is to carry out more and more illegal economic transactions or activities to produce individual or groups gains and then to legitimate them. Money laundering converts illicit source of money generated by criminal activities in order to hide the connection between money and their original illegal activities. This is one of money laundering side. The second side implies corruption. While money laundering is a passing channel for illicit funds due to its criminal origin source, such funds may derive from corruption offences. All corruption’s forms represent the most important illicit funds branches for money laundering process. Corrupt people methods used to exploit the national and international financial system reflect the relationship between those two criminal activities. Criminals achieve their personal interests by hiding their corruption proceeds and transfer these gains to official economies. Corruption spread in any society entails money laundering spread, and the converse, too. There is a quite “indecent” relationship between money laundering and corruption. This paper tries to identify the multiple connections between the two phenomenons showing the negative impacts these criminal behaviours are having on the national and international economy. We conclude by highlighting the necessity of a multidisciplinary approach in order to fight against money laundering and corruption by integrating these problem frameworks at national level. International community must focus their resources on money laundering and corruption risks areas and maximize their response impact.

  14. Biologic and synthetic skin substitutes: An overview.

    Science.gov (United States)

    Halim, Ahmad Sukari; Khoo, Teng Lye; Mohd Yussof, Shah Jumaat

    2010-09-01

    The current trend of burn wound care has shifted to more holistic approach of improvement in the long-term form and function of the healed burn wounds and quality of life. This has demanded the emergence of various skin substitutes in the management of acute burn injury as well as post burn reconstructions. Skin substitutes have important roles in the treatment of deep dermal and full thickness wounds of various aetiologies. At present, there is no ideal substitute in the market. Skin substitutes can be divided into two main classes, namely, biological and synthetic substitutes. The biological skin substitutes have a more intact extracellular matrix structure, while the synthetic skin substitutes can be synthesised on demand and can be modulated for specific purposes. Each class has its advantages and disadvantages. The biological skin substitutes may allow the construction of a more natural new dermis and allow excellent re-epithelialisation characteristics due to the presence of a basement membrane. Synthetic skin substitutes demonstrate the advantages of increase control over scaffold composition. The ultimate goal is to achieve an ideal skin substitute that provides an effective and scar-free wound healing.

  15. Biologic and synthetic skin substitutes: An overview

    Directory of Open Access Journals (Sweden)

    Halim Ahmad

    2010-10-01

    Full Text Available The current trend of burn wound care has shifted to more holistic approach of improvement in the long-term form and function of the healed burn wounds and quality of life. This has demanded the emergence of various skin substitutes in the management of acute burn injury as well as post burn reconstructions. Skin substitutes have important roles in the treatment of deep dermal and full thickness wounds of various aetiologies. At present, there is no ideal substitute in the market. Skin substitutes can be divided into two main classes, namely, biological and synthetic substitutes. The biological skin substitutes have a more intact extracellular matrix structure, while the synthetic skin substitutes can be synthesised on demand and can be modulated for specific purposes. Each class has its advantages and disadvantages. The biological skin substitutes may allow the construction of a more natural new dermis and allow excellent re-epithelialisation characteristics due to the presence of a basement membrane. Synthetic skin substitutes demonstrate the advantages of increase control over scaffold composition. The ultimate goal is to achieve an ideal skin substitute that provides an effective and scar-free wound healing.

  16. Stabilized ultrathin liquid membranes for gas separations

    International Nuclear Information System (INIS)

    Deetz, D.W.

    1987-01-01

    Although immobilized liquid membranes have the desirable properties of high selectivity and permeability, their practical application to gas phase separations is hindered because of the instability of the liquid phase and the relative thickness of current membranes. The problem of liquid instability, which is due to both liquid volatilization and flooding, can be reduced, or eliminated, by immobilizing the liquid phase in pores small enough to significantly reduce the molar free energy of the solution via the Kelvin effect. The obstacle of membrane thickness can be overcome by selectively immobilizing the liquid phase into the skin of a porous asymmetric membranes

  17. Membrane paradigm

    International Nuclear Information System (INIS)

    Price, R.H.; Thorne, K.S.

    1986-01-01

    The membrane paradigm is a modified frozen star approach to modeling black holes, with particles and fields assuming a complex, static, boundary-layer type structure (membrane) near the event horizon. The membrane has no effects on the present or future evolution of particles and fields above itself. The mathematical representation is a combination of a formalism containing terms for the shear and bulk viscosity, surface pressure, momentum, temperature, entropy, etc., of the horizon and the 3+1 formalism. The latter model considers a family of three-dimensional spacelike hypersurfaces in one-dimensional time. The membrane model considers a magnetic field threading the hole and undergoing torque from the hole rotation. The field is cleaned by the horizon and distributed over the horizon so that ohmic dissipation is minimized. The membrane paradigm is invalid inside the horizon, but is useful for theoretically probing the properties of slowly evolving black holes

  18. Membrane processes

    Science.gov (United States)

    Staszak, Katarzyna

    2017-11-01

    The membrane processes have played important role in the industrial separation process. These technologies can be found in all industrial areas such as food, beverages, metallurgy, pulp and paper, textile, pharmaceutical, automotive, biotechnology and chemical industry, as well as in water treatment for domestic and industrial application. Although these processes are known since twentieth century, there are still many studies that focus on the testing of new membranes' materials and determining of conditions for optimal selectivity, i. e. the optimum transmembrane pressure (TMP) or permeate flux to minimize fouling. Moreover the researchers proposed some calculation methods to predict the membrane processes properties. In this article, the laboratory scale experiments of membrane separation techniques, as well their validation by calculation methods are presented. Because membrane is the "heart" of the process, experimental and computational methods for its characterization are also described.

  19. Skin, Hair, and Nails

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Skin, Hair, and Nails KidsHealth / For Parents / Skin, Hair, and ... piel, el cabello y las uñas About Skin, Hair and Nails Skin is our largest organ. If ...

  20. Estrogens and aging skin

    OpenAIRE

    Thornton, M. Julie

    2013-01-01

    Estrogen deficiency following menopause results in atrophic skin changes and acceleration of skin aging. Estrogens significantly modulate skin physiology, targeting keratinocytes, fibroblasts, melanocytes, hair follicles and sebaceous glands, and improve angiogenesis, wound healing and immune responses. Estrogen insufficiency decreases defense against oxidative stress; skin becomes thinner with less collagen, decreased elasticity, increased wrinkling, increased dryness and reduced vascularity...

  1. Urostomy - stoma and skin care

    Science.gov (United States)

    ... it well before you attach the pouch. Avoid skin care products that contain alcohol. These can make your skin ... the pouch to your skin. Use fewer special skin care products. This will make problems with your skin less ...

  2. Risks of Skin Cancer Screening

    Science.gov (United States)

    ... factors increase or decrease the risk of skin cancer. Skin cancer is a disease in which malignant (cancer) ... following PDQ summaries for more information about skin cancer: Skin Cancer Prevention Skin Cancer Treatment Melanoma Treatment Genetics ...

  3. Calcipotriol delivery into the skin with PEGylated liposomes

    DEFF Research Database (Denmark)

    Knudsen, Nina Østergaard; Rønholt, Stine; Salte, Ragnhild Djønne

    2012-01-01

    The d-vitamin analogue calcipotriol is commonly used for topical treatment of psoriasis, but skin penetration is required for calcipotriol to reach its pharmacological target: the keratinocytes in the lower epidermis. Liposomes can enhance the delivery of drugs into the skin, but a major challenge...... of the liposomes and the ability to deliver membrane-intercalated calcipotriol into the skin. Inclusion of 0.5, l and 5mol% PEG-DSPE in the membrane enhanced the colloidal stability of the liposomes without compromising the delivery of calcipotriol from the vehicle into excised pig skin. Calcipotriol...... to large multilamellar vesicles, indicating that the liposomes to some extent migrate as intact vesicles into the stratum corneum. However, calcipotriol penetrated the skin better than the lipid component of the liposomes, suggesting that at least a fraction of the drug is released from the liposomes...

  4. Primordial membranes

    DEFF Research Database (Denmark)

    Hanczyc, Martin M; Monnard, Pierre-Alain

    2017-01-01

    Cellular membranes, which are self-assembled bilayer structures mainly composed of lipids, proteins and conjugated polysaccharides, are the defining feature of cell physiology. It is likely that the complexity of contemporary cells was preceded by simpler chemical systems or protocells during...... the various evolutionary stages that led from inanimate to living matter. It is also likely that primitive membranes played a similar role in protocell 'physiology'. The composition of such ancestral membranes has been proposed as mixtures of single hydrocarbon chain amphiphiles, which are simpler versions...

  5. Electrospun superhydrophobic membranes with unique structures for membrane distillation.

    Science.gov (United States)

    Liao, Yuan; Loh, Chun-Heng; Wang, Rong; Fane, Anthony G

    2014-09-24

    With modest temperature demand, low operating pressure, and high solute rejection, membrane distillation (MD) is an attractive option for desalination, waste treatment, and food and pharmaceutical processing. However, large-scale practical applications of MD are still hindered by the absence of effective membranes with high hydrophobicity, high porosity, and adequate mechanical strength, which are important properties for MD permeation fluxes, stable long-term performance, and effective packing in modules without damage. This study describes novel design strategies for highly robust superhydrophobic dual-layer membranes for MD via electrospinning. One of the newly developed membranes comprises a durable and ultrathin 3-dimensional (3D) superhydrophobic skin and porous nanofibrous support whereas another was fabricated by electrospinning 3D superhydrophobic layers on a nonwoven support. These membranes exhibit superhydrophobicity toward distilled water, salty water, oil-in-water emulsion, and beverages, which enables them to be used not only for desalination but also for other processes. The superhydrophobic dual-layer membrane #3S-N with nanofibrous support has a competitive permeation flux of 24.6 ± 1.2 kg m(-2) h(-1) in MD (feed and permeate temperate were set as 333 and 293 K, respectively) due to the higher porosity of the nanofibrous scaffold. Meanwhile, the membranes with the nonwoven support exhibit greater mechanical strength due to this support combined with better long-term performance because of the thicker 3D superhydrophobic layers. The morphology, pore size, porosity, mechanical properties, and liquid enter pressure of water of these superhydrophobic composite membranes with two different structures are reported and compared with commercial polyvinylidene fluoride membranes.

  6. Use of autologous tissue engineered skin to treat porcine full-thickness skin defects

    Institute of Scientific and Technical Information of China (English)

    CAI Xia; CAO Yi-lin; CUI Lei; LIU Wei; GUAN Wen-xiang

    2005-01-01

    Objective: To explore a feasible method to repair full-thickness skin defects utilizing tissue engineered techniques. Methods: The Changfeng hybrid swines were used and the skin specimens were cut from the posterior limb girdle region, from which the keratinocytes and fibroblasts were isolated and harvested by trypsin, EDTA, and type II collagenase. The cells were seeded in Petri dishes for primary culture. When the cells were in logarithmic growth phase, they were treated with trypsin to separate them from the floor of the tissue culture dishes. A biodegradable material, Pluronic F-127, was prefabricated and mixed with these cells, and then the cell-Pluronic compounds were seeded evenly into a polyglycolic acid (PGA). Then the constructs were replanted to the autologous animals to repair the full-thickness skin defects. Histology and immunohistochemistry of the neotissue were observed in 1, 2, 4, and 8 postoperative weeks. Results: The cell-Pluronic F-127-PGA compounds repaired autologous full-thickness skin defects 1 week after implantation. Histologically, the tissue engineered skin was similar to the normal skin with stratified epidermis overlying a moderately thick collageneous dermis. Three of the structural proteins in the epidermal basement membrane zone, type IV collagen, laminin, and type VII collagen were detected using immunohistochemical methods. Conclusions: By studying the histology and immunohistochemistry of the neotissue, the bioengineered skin graft holds great promise for improving healing of the skin defects.

  7. Oily skin: an overview.

    Science.gov (United States)

    Sakuma, Thais H; Maibach, Howard I

    2012-01-01

    Oily skin (seborrhea) is a common cosmetic problem that occurs when oversized sebaceous glands produce excessive amounts of sebum giving the appearance of shiny and greasy skin. This paper overviews the main concepts of sebaceous gland anatomy and physiology, including the biosynthesis, storage and release of sebum, as well as its relationship to skin hydration and water barrier function. We also address how skin oiliness may vary according to diet, age, gender, ethnicity and hot humid climates. The deeper understanding of this skin type provides the opportunity to better guide patients regarding skin care and also assist in the development of sebosuppressive agents. Copyright © 2012 S. Karger AG, Basel.

  8. Human skin penetration of silver nanoparticles through intact and damaged skin

    International Nuclear Information System (INIS)

    Larese, Francesca Filon; D'Agostin, Flavia; Crosera, Matteo; Adami, Gianpiero; Renzi, Nadia; Bovenzi, Massimo; Maina, Giovanni

    2009-01-01

    There is a growing interest on nanoparticle safety for topical use. The benefits of nanoparticles have been shown in several scientific fields, but little is known about their potential to penetrate the skin. This study aims at evaluating in vitro skin penetration of silver nanoparticles. Experiments were performed using the Franz diffusion cell method with intact and damaged human skin. Physiological solution was used as receiving phase and 70 μg/cm 2 of silver nanoparticles coated with polyvinylpirrolidone dispersed in synthetic sweat were applied as donor phase to the outer surface of the skin for 24 h. The receptor fluid measurements were performed by electro thermal atomic absorption spectroscopy (ETAAS). Human skin penetration was also determined by using transmission electron microscope (TEM) to verify the location of silver nanoparticles in exposed membranes. Median silver concentrations of 0.46 ng cm -2 (range -2 (range 0.43-11.6) were found in the receiving solutions of cells where the nanoparticles solution was applied on intact skin (eight cells) and on damaged skin (eight cells), respectively. Twenty-four hours silver flux permeation in damaged skin was 0.62 ± 0.2 ng cm -2 with a lag time <1 h. Our experimental data showed that silver nanoparticles absorption through intact and damaged skin was very low but detectable, and that in case of damaged skin it was possible an increasing permeation of silver applied as nanoparticles. Moreover, silver nanoparticles could be detected in the stratum corneum and the outermost surface of the epidermis by electron microscopy. We demonstrated for the first time that silver applied as nanoparticles coated with polyvinylpirrolidone is able to permeate the damaged skin in an in vitro diffusion cell system

  9. The use of allodermis prepared from Euro skin bank to prepare autologous tissue engineered skin for clinical use.

    Science.gov (United States)

    Deshpande, P; Ralston, D R; MacNeil, S

    2013-09-01

    Over the past two decades a range of 3D models for human skin have been described. Some include native collagen and intrinsic basement membrane proteins and fibroblasts, others are based on xenogeneic collagen or synthetic supports often without fibroblasts. The aim of this study was to look at the influence of media calcium, basement membrane and fibroblasts on the quality of 3D tissue engineered skin produced using human de-epidermized acellular dermis. In this study we deliberately used Euro skin as the source of the donor dermis to examine to what extent this could provide an effective dermal substrate for producing 3D skin for clinical use. Keratinocytes were cultured in the presence and absence of fibroblasts and both with and without basement membrane on decellularized dermis at calcium concentrations ranging from 250μM to 1.6mM over a period of 14 days. Results showed the formation of a well attached epithelium with many of the features of normal skin in the presence of a basement membrane. This was largely independent of the presence of fibroblasts and not greatly influenced by the concentration of calcium in the media. However there was a clear requirement for physiological levels of calcium in the formation of a stratified epithelium in the absence of a basement membrane. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  10. Skin Stem Cells in Skin Cell Therapy

    Directory of Open Access Journals (Sweden)

    Mollapour Sisakht

    2015-12-01

    Full Text Available Context Preclinical and clinical research has shown that stem cell therapy is a promising therapeutic option for many diseases. This article describes skin stem cells sources and their therapeutic applications. Evidence Acquisition Compared with conventional methods, cell therapy reduces the surgical burden for patients because it is simple and less time-consuming. Skin cell therapy has been developed for variety of diseases. By isolation of the skin stem cell from the niche, in vitro expansion and transplantation of cells offers a surprising healing capacity profile. Results Stem cells located in skin cells have shown interesting properties such as plasticity, transdifferentiation, and specificity. Mesenchymal cells of the dermis, hypodermis, and other sources are currently being investigated to promote regeneration. Conclusions Because skin stem cells are highly accessible from autologous sources and their immunological profile is unique, they are ideal for therapeutic approaches. Optimization of administrative routes requires more investigation own to the lack of a standard protocol.

  11. Examine Your Skin

    Science.gov (United States)

    ... Support Donate Share Facebook Twitter Newsletter Examine Your Skin Watch the video below and in only two minutes, you can learn to examine your skin. A special thanks to Dr. Martin Weinstock, MD, ...

  12. Examine Your Skin

    Medline Plus

    Full Text Available ... Support Donate Share Facebook Twitter Newsletter Examine Your Skin Watch the video below and in only two minutes, you can learn to examine your skin. A special thanks to Dr. Martin Weinstock, MD, ...

  13. Bleeding into the skin

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003235.htm Bleeding into the skin To use the sharing features on this page, please enable JavaScript. Bleeding into the skin can occur from broken blood ...

  14. Mantoux Tuberculin Skin Test

    Centers for Disease Control (CDC) Podcasts

    Learn how to evaluate people for latent TB infection with the Mantoux tuberculin skin test. This podcast includes sections on administering and reading the Mantoux tuberculin skin test, the standard method for detecting latent TB infection since the 1930s.

  15. Skin graft - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100100.htm Skin graft - series—Normal anatomy To use the sharing features ... entire body, and acts as a protective barrier. Skin grafts may be recommended for: Extensive wounds Burns Specific ...

  16. Laser surgery - skin

    Science.gov (United States)

    ... Bleeding Problem not going away Infection Pain Scarring Skin color changes Some laser surgery is done when you are asleep and ... TG, Elston DM, eds. Andrews' Diseases of the Skin: Clinical ... lasers, lights, and tissue interactions. In: Hruza GJ, Avram ...

  17. Examine Your Skin

    Medline Plus

    Full Text Available ... Suggestions Examine Your Skin Newly Diagnosed? Understanding Your Pathology Biopsy: The First Step Sentinel Node Biopsy Melanoma ... Suggestions Examine Your Skin Newly Diagnosed? Understanding Your Pathology Biopsy: The First Step Sentinel Node Biopsy Melanoma ...

  18. Axionic membranes

    International Nuclear Information System (INIS)

    Aurilia, A.; Spallucci, E.

    1992-01-01

    A metal ring removed from a soap-water solution encloses a film of soap which can be mathematically described as a minimal surface having the ring as its only boundary. This is known to everybody. In this letter we suggest a relativistic extension of the above fluidodynamic system where the soap film is replaced by a Kalb-Ramand gauge potential B μν (x) and the ring by a closed string. The interaction between the B μν field and the string current excites a new configuration of the system consisting of a relativistic membrane bounded by the string. We call such a classical solution of the equation of motion an axionic membrane. As a dynamical system, the axionic membrane admits a Hamilton-Jacobi formulation which is an extension of the HJ theory of electromagnetic strings. (orig.)

  19. In-vitro percutaneous absorption of losartan potassium in human skin and prediction of human skin permeability

    Directory of Open Access Journals (Sweden)

    Petkar K.C.

    2007-05-01

    Full Text Available This study describes the feasibility of transdermal controlled administration of Losartan potassium (LP across human cadaver skin. Study also defines the influence of capsaicin, sex and site of application on permeation characteristics and determined an appropriate animal model for human skin permeability. The permeation of LP of various formulations was studied using Keshary-Chein diffusion cell. Optimized controlled formulation (without capsaicin released 42.17% (±1.85 of LP in 12 hr whereas treatment formulation (with capsaicin 0.028 % w/v released 48.94% (±1.71 of LP with significant difference on null hypothesis. Influence of sex showed statistically significant difference for permeation of LP through male and female rats, as well as male and female mice across both the abdominal and dorsal sides of the skin (p<0.05. Similarly statistically significant differences were noted for permeation of LP across male and female mice abdomen-dorsal, but not for male rat abdomen-dorsal and female rat abdomen-dorsal. Furthermore, in-vitro permeation of LP across human skin was compared with the permeation across rat and mice skins. Male rat and male mice dorsal skin was found to have closer permeability characteristics to human than other skin membranes, but the Factor of Difference values were < 3 for all membranes which were used suggesting the membranes are good models for human skin permeability. In conclusion simple transdermal adhesive patches formulations incorporating high molecular weight of LP can deliver a dose in-vivo and proposed model skin membranes can be utilized for future pharmacokineic and toxicokinetic studies as well as metabolism studies of LP

  20. Electroosmotic pore transport in human skin.

    Science.gov (United States)

    Uitto, Olivia D; White, Henry S

    2003-04-01

    To determine the pathways and origin of electroosmotic flow in human skin. Iontophoretic transport of acetaminophen in full thickness human cadaver skin was visualized and quantified by scanning electrochemical microscopy. Electroosmotic flow in the shunt pathways of full thickness skin was compared to flow in the pores of excised stratum corneum and a synthetic membrane pore. The penetration of rhodamine 6G into pore structures was investigated by laser scanning confocal microscopy. Electroosmotic transport is observed in shunt pathways in full thickness human skin (e.g., hair follicles and sweat glands), but not in pore openings of freestanding stratum corneum. Absolute values of the diffusive and iontophoretic pore fluxes of acetaminophen in full thickness human skin are also reported. Rhodamine 6G is observed to penetrate to significant depths (approximately 200 microm) along pore pathways. Iontophoresis in human cadaver skin induces localized electroosmotic flow along pore shunt paths. Electroosmotic forces arise from the passage of current through negatively charged mesoor nanoscale pores (e.g., gap functions) within cellular regions that define the pore structure beneath the stratum corneum.

  1. Metamaterial membranes

    International Nuclear Information System (INIS)

    Restrepo-Flórez, Juan Manuel; Maldovan, Martin

    2017-01-01

    We introduce a new class of metamaterial device to achieve separation of compounds by using coordinate transformations and metamaterial theory. By rationally designing the spatial anisotropy for mass diffusion, we simultaneously concentrate different compounds in different spatial locations, leading to separation of mixtures across a metamaterial membrane. The separation of mixtures into their constituent compounds is critically important in biophysics, biomedical, and chemical applications. We present a practical case where a mixture of oxygen and nitrogen diffusing through a polymeric planar matrix is separated. This work opens doors to new paradigms in membrane separations via coordinate transformations and metamaterials by introducing novel properties and unconventional mass diffusion phenomena. (paper)

  2. Skin self-exam

    Science.gov (United States)

    Skin cancer - self-exam; Melanoma - self-exam; Basal cell cancer - self-exam; Squamous cell - self-exam; Skin mole - self-exam ... Checking your skin regularly can help you notice any unusual changes. Follow your health care provider's recommendations on how often to ...

  3. Skin Conditions during Pregnancy

    Science.gov (United States)

    ... during pregnancy. For most skin changes, however, health care providers are not sure of the exact cause. Why do dark spots and patches appear on the skin during pregnancy? Dark spots and patches are caused by an increase in the body’s melanin—a natural substance that gives color to the skin and ...

  4. Psychoneuroimmunology and the Skin.

    Science.gov (United States)

    Honeyman, Juan F

    2016-08-23

    The nervous, immune, endocrine and integumentary systems are closely related and interact in a number of normal and pathological conditions. Nervous system mediators may bring about direct changes to the skin or may induce the release of immunological or hormonal mediators that cause pathological changes to the skin. This article reviews the psychological mechanisms involved in the development of skin diseases.

  5. Skin layer mechanics

    NARCIS (Netherlands)

    Geerligs, M.

    2010-01-01

    The human skin is composed of several layers, each with an unique structure and function. Knowledge about the mechanical behavior of these skin layers is important for clinical and cosmetic research, such as the development of personal care products and the understanding of skin diseases. Until

  6. Polymer and Membrane Design for Low Temperature Catalytic Reactions

    KAUST Repository

    Villalobos, Luis Francisco

    2016-02-29

    Catalytically active asymmetric membranes have been developed with high loadings of palladium nanoparticles located solely in the membrane\\'s ultrathin skin layer. The manufacturing of these membranes requires polymers with functional groups, which can form insoluble complexes with palladium ions. Three polymers have been synthesized for this purpose and a complexation/nonsolvent induced phase separation followed by a palladium reduction step is carried out to prepare such membranes. Parameters to optimize the skin layer thickness and porosity, the palladium loading in this layer, and the palladium nanoparticles size are determined. The catalytic activity of the membranes is verified with the reduction of a nitro-compound and with a liquid phase Suzuki-Miyaura coupling reaction. Very low reaction times are observed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Socio-motivational moderators – Two sides of the same coin?Testing the potential buffering role of socio-motivational relationships on achievement drive and test anxiety among German and Canadian secondary school students

    Directory of Open Access Journals (Sweden)

    Frances eHoferichter

    2015-10-01

    Full Text Available The current cross-national study investigates the potential buffering role of socio-motivational relationships for the association of achievement drive and test anxiety in secondary school students from Canada and Germany. One thousand eighty-eight students (54% girls, Mage = 13.71, SD = .53, age span 12–15 years from the state of Brandenburg and 389 students from Quebéc (55.9% girls, Mage = 13.43, SD = .82, age span 12–16 years were asked about their socio-motivational relationships with their teachers and peers, their drive for achievement, and test anxiety. Multigroup latent moderated structural equations (MGLMS were conducted to test for the moderator role of socio-motivational relationships that would buffer feelings of test anxiety related to the drive for achievement. The analyses revealed the two-sided role socio-motivational relationships can have for students with different levels of achievement drive; intensifying or mitigating feelings of test anxiety. Thereby, the results of this study extend the buffering hypothesis by Cohen and Wills (1985. Cross-national differences between Canada and Germany were found concerning the studied moderators on the association of achievement drive and test anxiety: While for German students teacher-student relationships acted as moderator, for Canadian students student-student relationships and teachers acting as positive motivators displayed a moderator role.

  8. Socio-motivational moderators—two sides of the same coin? Testing the potential buffering role of socio-motivational relationships on achievement drive and test anxiety among German and Canadian secondary school students

    Science.gov (United States)

    Hoferichter, Frances; Raufelder, Diana; Eid, Michael

    2015-01-01

    The current cross-national study investigates the potential buffering role of socio-motivational relationships for the association of achievement drive (AD) and test anxiety (TX) in secondary school students from Canada and Germany. One thousand and eighty-eight students (54% girls, Mage = 13.71, SD = 0.53, age span 12–15 years) from the state of Brandenburg and 389 students from Quebéc (55.9% girls, Mage = 13.43, SD = 0.82, age span 12–16 years) were asked about their socio-motivational relationships with their teachers and peers, their drive for achievement, and TX. Multigroup latent moderated structural equations were conducted to test for the moderator role of socio-motivational relationships that would buffer feelings of TX related to the drive for achievement. The analyses revealed the two-sided role socio-motivational relationships can have for students with different levels of AD; intensifying or mitigating feelings of TX. Thereby, the results of this study extend the buffering hypothesis by Cohen and Wills (1985). Cross-national differences between Canada and Germany were found concerning the studied moderators on the association of AD and TX: While for German students teacher–student relationships acted as moderator, for Canadian students student–student relationships and teachers acting as positive motivators displayed a moderator role. PMID:26583000

  9. Socio-motivational moderators-two sides of the same coin? Testing the potential buffering role of socio-motivational relationships on achievement drive and test anxiety among German and Canadian secondary school students.

    Science.gov (United States)

    Hoferichter, Frances; Raufelder, Diana; Eid, Michael

    2015-01-01

    The current cross-national study investigates the potential buffering role of socio-motivational relationships for the association of achievement drive (AD) and test anxiety (TX) in secondary school students from Canada and Germany. One thousand and eighty-eight students (54% girls, M age = 13.71, SD = 0.53, age span 12-15 years) from the state of Brandenburg and 389 students from Quebéc (55.9% girls, M age = 13.43, SD = 0.82, age span 12-16 years) were asked about their socio-motivational relationships with their teachers and peers, their drive for achievement, and TX. Multigroup latent moderated structural equations were conducted to test for the moderator role of socio-motivational relationships that would buffer feelings of TX related to the drive for achievement. The analyses revealed the two-sided role socio-motivational relationships can have for students with different levels of AD; intensifying or mitigating feelings of TX. Thereby, the results of this study extend the buffering hypothesis by Cohen and Wills (1985). Cross-national differences between Canada and Germany were found concerning the studied moderators on the association of AD and TX: While for German students teacher-student relationships acted as moderator, for Canadian students student-student relationships and teachers acting as positive motivators displayed a moderator role.

  10. Taking Care of Your Skin

    Science.gov (United States)

    ... Educators Search English Español Taking Care of Your Skin KidsHealth / For Kids / Taking Care of Your Skin ... you're in. Why Be Nice to Your Skin? Like the heart, stomach, and brain, your skin ...

  11. Chelating polymeric membranes

    KAUST Repository

    Peinemann, Klaus-Viktor; Villalobos Vazquez de la Parra, Luis Francisco; Hilke, Roland

    2015-01-01

    microporous chelating polymeric membrane. Embodiments include, but are not limited to, microporous chelating polymeric membranes, device comprising the membranes, and methods of using and making the same.

  12. SKIN CARE IN INFANTS

    Directory of Open Access Journals (Sweden)

    I. N. Zakharova

    2014-01-01

    Full Text Available Human skin is a complex organ in its structure. Numerous functions of the skin may be impaired in its pathology. Anatomical and physiological characteristics of the skin in children predispose to common diseases of the skin. Diaper dermatitis is one of the most common skin diseases during infancy and childhood. Diapered skin is exposed to friction and excessive hydration, has a higher pH than nondiapered skin, and is repeatedly soiled with feces that contains enzymes with high irritation potential for the skin. Diaper dermatitis may vary in clinical severity and course. Therapeutically, frequent diaper changes and adequate skin care are most important. Appropriate skin care can help to prevent the occurrence of diaper dermatitis and to speed up the healing of affected skin. This includes frequent diaper changes and aeration, gentle cleansing, and the use of a barrier cream. For the treatment of diaper dermatitis agents selected depending on the presence and severity of complications. For prevention and treatment of uncomplicated diaper dermatitis effective means of containing dexpantenol.

  13. Nutrition and skin.

    Science.gov (United States)

    Pappas, Apostolos; Liakou, Aikaterini; Zouboulis, Christos C

    2016-09-01

    Nutrition has long been associated with skin health, including all of its possible aspects from beauty to its integrity and even the aging process. Multiple pathways within skin biology are associated with the onset and clinical course of various common skin diseases, such as acne, atopic dermatitis, aging, or even photoprotection. These conditions have been shown to be critically affected by nutritional patterns and dietary interventions where well-documented studies have demonstrated beneficial effects of essential nutrients on impaired skin structural and functional integrity and have restored skin appearance and health. Although the subject could be vast, the intention of this review is to provide the most relevant and the most well-documented information on the role of nutrition in common skin conditions and its impact on skin biology.

  14. Fabrication of bioinspired composite nanofiber membranes with robust superhydrophobicity for direct contact membrane distillation.

    Science.gov (United States)

    Liao, Yuan; Wang, Rong; Fane, Anthony G

    2014-06-03

    The practical application of membrane distillation (MD) for water purification is hindered by the absence of desirable membranes that can fulfill the special requirements of the MD process. Compared to the membranes fabricated by other methods, nanofiber membranes produced by electrospinning are of great interest due to their high porosity, low tortuosity, large surface pore size, and high surface hydrophobicity. However, the stable performance of the nanofiber membranes in the MD process is still unsatisfactory. Inspired by the unique structure of the lotus leaf, this study aimed to develop a strategy to construct superhydrophobic composite nanofiber membranes with robust superhydrophobicity and high porosity suitable for use in MD. The newly developed membrane consists of a superhydrophobic silica-PVDF composite selective skin formed on a polyvinylidene fluoride (PVDF) porous nanofiber scaffold via electrospinning. This fabrication method could be easily scaled up due to its simple preparation procedures. The effects of silica diameter and concentration on membrane contact angle, sliding angle, and MD performance were investigated thoroughly. For the first time, the direct contact membrane distillation (DCMD) tests demonstrate that the newly developed membranes are able to present stable high performance over 50 h of testing time, and the superhydrophobic selective layer exhibits excellent durability in ultrasonic treatment and a continuous DCMD test. It is believed that this novel design strategy has great potential for MD membrane fabrication.

  15. Skin absorption through atopic dermatitis skin

    DEFF Research Database (Denmark)

    Halling-Overgaard, A-S; Kezic, S; Jakasa, I

    2017-01-01

    Patients with atopic dermatitis have skin barrier impairment in both lesional and non-lesional skin. They are typically exposed to emollients daily and topical anti-inflammatory medicaments intermittently, hereby increasing the risk of developing contact allergy and systemic exposed to chemicals...... ingredients found in these topical preparations. We systematically searched for studies that investigated skin absorption of various penetrants, including medicaments, in atopic dermatitis patients, but also animals with experimentally induced dermatitis. We identified 40 articles, i.e. 11 human studies...... examining model penetrants, 26 human studies examining atopic dermatitis drugs and 3 animal studies. We conclude that atopic dermatitis patients have nearly two-fold increased skin absorption when compared to healthy controls. There is a need for well-designed epidemiological and dermato...

  16. Biocompatibility of epoxidized styrene-butadiene-styrene block copolymer membrane

    International Nuclear Information System (INIS)

    Yang, Jen Ming; Tsai, Shih Chang

    2010-01-01

    Styrene-butadiene-styrene block copolymer (SBS) membrane was prepared by solution casting method and then was epoxidized with peroxyformic acid generated in situ to yield the epoxidized styrene-butadiene-styrene block copolymer membrane (ESBS). The structure and properties of ESBS were characterized with infrared spectroscopy, Universal Testing Machine, differential scanning calorimetry (DSC), and thermogravimetry analysis (TGA). The performances of contact angle, water content, protein adsorption, and water vapor transmission rate on ESBS membrane were determined. After epoxidation, the hydrophilicity of the membrane increased. The water vapor transmission rate of ESBS membrane is similar to human skin. The biocompatibility of ESBS membrane was evaluated with the cell culture of fibroblasts on the membrane. It revealed that the cells not only remained viable but also proliferated on the surface of the various ESBS membranes and the population doubling time for fibroblast culture decreased.

  17. Latest development on the membrane formation for gas separation

    Directory of Open Access Journals (Sweden)

    Ahmad Fausi Ismail

    2002-11-01

    Full Text Available The first scientific observation related to gas separation was encountered by J.K Mitchell in 1831. However, the most remarkable and influential contribution to membrane gas separation technology was the systematic study by Thomas Graham in 1860. However only in 1979, membrane based gas separation technology was available and recognized as one of the most recent and advanced unit operations for gas separation processes. Membrane is fabricated by various methods and the parameters involved to a certain extent are very complicated. The phase inversion technique that is normally employed to produce membranes are dry/wet, wet, dry and thermal induced phase separation. Other techniques used to produce membrane are also reviewed. This paper reports the latest development in membrane formation for gas separation. The route to produce defect-free and ultrathin-skinned asymmetric membrane is also presented that represents the cutting edge technology in membrane gas separation process

  18. Poly/vinyl alcohol/ membranes for reverse osmosis

    Science.gov (United States)

    Katz, M. G.; Wydeven, T., Jr.

    1981-01-01

    A description is presented of the results of studies of the water and salt transport properties of PVA membranes, taking into account radiation crosslinked PVA membranes, diffusive salt permeability through PVA membranes, and heat treated PVA membranes. The experimental findings support an occurrence of independent water, and salt permeation processes. It is suggested that the salt permeation is governed by a solution-diffusion transport mechanism. The preparation of thin skinned, asymmetric PVA membranes is also discussed. The employed method has a certain similarity to the classical phase inversion method, which is widely applied in the casting of asymmetric reverse osmosis membranes. Instead of using a gelling bath composed of a nonsolvent for the membrane material and miscible with the solvent from which the membrane is cast, a 'complexing' bath is used, which is a solution of a complexing agent in water.

  19. Uptake of macromolecules by cercariae during skin penetration and transformation to schistosomula (Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Joyce Thornhill

    2010-07-01

    Full Text Available Here, we observed the uptake of membrane-impermeant molecules by cercariae as they penetrate the skin and are transformed into schistosomula. We propose that membrane-impermeant molecules, Lucifer Yellow, Propidium iodide and Hoechst 33258 enter the parasite through both thenephridiopore and the surface membrane and then diffuse throughout the body of the parasite. We present a hypothesis that the internal cells of the body of the schistosomulum represent a new host-parasite interface, at which skin-derived growth factors may stimulate receptors on internal membranes during transformation of the cercariae into the schistosomulum.

  20. New Polymeric Membranes for Organic Solvent Nanofiltration

    KAUST Repository

    Aburabie, Jamaliah

    2017-05-01

    The focus of this dissertation was the development, synthesis and modification of polymers for the preparation of membranes for organic solvent nanofiltration. High chemical stability in a wide range of solvents was a key requirement. Membranes prepared from synthesized polymers as well as from commercial polymers were designed and chemically modified to reach OSN requirements. A solvent stable thin-film composite (TFC) membrane is reported, which is fabricated on crosslinked polythiosemicarbazide (PTSC) as substrate. The membranes exhibited high fluxes towards solvents like THF, DMF and DMSO ranging around 20 L/m2 h at 5 bar with a MWCO of around 1000 g/mol. Ultrafiltration PTSC membranes were prepared by non-solvent induced phase separation and crosslinked with GPTMS. The crosslinking reaction was responsible for the formation of an inorganic-type-network that tuned the membrane pore size. The crosslinked membranes acquired high solvent stability in DMSO, DMF and THF with a MWCO above 1300 g/mol. Reaction Induced Phase Separation (RIPS) was introduced as a new method for the preparation of skinned asymmetric membranes. These membranes have two distinctive layers with different morphologies both from the same polymer. The top dense layer is composed of chemically crosslinked polymer chains while the bottom layer is a porous structure formed by non-crosslinked polymer chains. Such membranes were tested for vitamin B12 in solvents after either crosslinking the support or dissolving the support and fixing the freestanding membrane on alumina. Pebax® 1657 was utilized for the preparation of composite membranes by simple coating. Porous PAN membranes were coated with Pebax® 1657 which was then crosslinked using TDI. Crosslinked Pebax® membranes show high stability towards ethanol, propanol and acetone. The membranes were also stable in DMF once crosslinked PAN supports were used. Sodium alginate polymer was investigated for the preparation of thin film composite

  1. Characterization of anisotropic UF-membranes: top layer thickness and pore structure

    NARCIS (Netherlands)

    Cuperus, F.P.; Cuperus, F.P.; Bargeman, D.; Bargeman, D.; Smolders, C.A.; Smolders, C.A.

    1991-01-01

    Anisotropic poly(2,6-dimethyl-, 1,4-phenylene oxide) (PPO) ultrafiltration membranes are characterized by means of two techniques. A new method for the determination of skin thicknesses, the gold sol method, is introduced and applied to these membranes. The membranes appeared to have a well-defined

  2. Dois lados de uma mesma moeda: A dissolução da economia clássica e o nascimento da Sociologia (Two sides of the same coin: The dissolution of classic economy and the birth of Sociology

    Directory of Open Access Journals (Sweden)

    Ranieri Carli

    2009-01-01

    Full Text Available Resumo: Este artigo pretende delinear os contornos do que Georg Lukács chama de “movimento de decadência ideológica da burguesia”, o qual significa uma passagem no plano da teoria da racionalidade ao formalismo e que corresponde à passagem no plano político da revolução à manutenção para a classe burguesa. Analisaremos as suas consequências especialmente na economia política e na Sociologia. A ideia desenvolvida é que tanto a dissolução da economia clássica quanto o nascimento da Sociologia são dois lados de uma mesma moeda: fazem parte do que Lukács chamou de “destruição da razão burguesa”. Para concluir, a análise a ser feita será a propósito da herança cultural do pensamento progressista burguês.Abstract: This article aims at delineating the outlines of what Georg Lukács calls “movement of ideological decay of the bourgeoisie”, which means a transition in the theoretical plan from the rationality to the formalism that corresponds to the transition in the political plan from the revolution to the maintenance for the bourgeois class. The analysis will focus especially on its consequences in terms of political economy and sociology. The idea developed is that the dissolution of the traditional economy as the birth of sociology represents two sides of the same coin, being part of what Lukács called the “destruction of bourgeois reason”. In conclusion, the following analysis will examine the cultural inheritance of the bourgeois progressive thought.

  3. Skin barrier function

    DEFF Research Database (Denmark)

    2016-01-01

    Renowned experts present the latest knowledge Although a very fragile structure, the skin barrier is probably one of the most important organs of the body. Inward/out it is responsible for body integrity and outward/in for keeping microbes, chemicals, and allergens from penetrating the skin. Since...... the role of barrier integrity in atopic dermatitis and the relationship to filaggrin mutations was discovered a decade ago, research focus has been on the skin barrier, and numerous new publications have become available. This book is an interdisciplinary update offering a wide range of information...... on the subject. It covers new basic research on skin markers, including results on filaggrin and on methods for the assessment of the barrier function. Biological variation and aspects of skin barrier function restoration are discussed as well. Further sections are dedicated to clinical implications of skin...

  4. Recommendations for skin decontamination

    International Nuclear Information System (INIS)

    1989-01-01

    Further to the reecommendations for determining the surface contamination of the skin and estimating the radiation exposure of the skin after contamination (SAAS-Mitt--89-16), measures for skin decontamination are recommended. They are necessary if (1) after simple decontamination by means of water, soap and brush without damaging the skin the surface contamination limits are exceeded and the radiation exposure to be expected for the undamaged healthy skin is estimated as to high, and if (2) a wound is contaminated. To remove skin contaminations, in general universally applicable, non-aggressive decontamination means and methods are sufficient. In special cases, nuclide-specific decontamination is required taking into account the properties of the radioactive substance

  5. STUDI MEMBRAN KITOSAN DARI KULIT LOBSTER BAMBU SEBAGAI MEMBRAN FILTRASI

    Directory of Open Access Journals (Sweden)

    Ni Nyoman Putri Windari

    2016-02-01

    Full Text Available The study of the extraction and characterization of chitosan from skin waste of Bamboo Lobster (Panulirus versicolor has been done. Chitosan is extracted using conventional method, namely the initial process: cleaning and drying (pretreatment, demineralization, deproteination, and deacetylation. The chitosan obtained has been used to prepare chitosan membrane 2% with acetic acid 1% as solvent. The membrane prepared by phase inversion method withprecipitation through solvent evaporation. The prepared membranes were characterized by FTIR spectrophotometer, Nova 1200e by BJH method and filtration method. The results obtained that degree of deacetylation (DD of chitosan is 70.016%. The thickness of the membrane is 0.361 mm. The FTIR spectra show that functional groups obtained are -NH, -CH, C=O, C-O and -CN. From BJH method obtained that the pore radius is 1.69 nm and pore density is 8.95 x 105pores/m3. From the filtration method obtained that at each pressure, 80-85 kPa and 90-100 kPa, the PWF values are 381.232 and 454.545 L/m2.h, respectively.

  6. Biomimetic shark skin: design, fabrication and hydrodynamic function.

    Science.gov (United States)

    Wen, Li; Weaver, James C; Lauder, George V

    2014-05-15

    Although the functional properties of shark skin have been of considerable interest to both biologists and engineers because of the complex hydrodynamic effects of surface roughness, no study to date has successfully fabricated a flexible biomimetic shark skin that allows detailed study of hydrodynamic function. We present the first study of the design, fabrication and hydrodynamic testing of a synthetic, flexible, shark skin membrane. A three-dimensional (3D) model of shark skin denticles was constructed using micro-CT imaging of the skin of the shortfin mako (Isurus oxyrinchus). Using 3D printing, thousands of rigid synthetic shark denticles were placed on flexible membranes in a controlled, linear-arrayed pattern. This flexible 3D printed shark skin model was then tested in water using a robotic flapping device that allowed us to either hold the models in a stationary position or move them dynamically at their self-propelled swimming speed. Compared with a smooth control model without denticles, the 3D printed shark skin showed increased swimming speed with reduced energy consumption under certain motion programs. For example, at a heave frequency of 1.5 Hz and an amplitude of ± 1 cm, swimming speed increased by 6.6% and the energy cost-of-transport was reduced by 5.9%. In addition, a leading-edge vortex with greater vorticity than the smooth control was generated by the 3D printed shark skin, which may explain the increased swimming speeds. The ability to fabricate synthetic biomimetic shark skin opens up a wide array of possible manipulations of surface roughness parameters, and the ability to examine the hydrodynamic consequences of diverse skin denticle shapes present in different shark species. © 2014. Published by The Company of Biologists Ltd.

  7. Polymer and Membrane Design for Low Temperature Catalytic Reactions

    KAUST Repository

    Villalobos, Luis Francisco; Xie, Yihui; Nunes, Suzana Pereira; Peinemann, Klaus-Viktor

    2016-01-01

    Catalytically active asymmetric membranes have been developed with high loadings of palladium nanoparticles located solely in the membrane's ultrathin skin layer. The manufacturing of these membranes requires polymers with functional groups, which can form insoluble complexes with palladium ions. Three polymers have been synthesized for this purpose and a complexation/nonsolvent induced phase separation followed by a palladium reduction step is carried out to prepare such membranes. Parameters to optimize the skin layer thickness and porosity, the palladium loading in this layer, and the palladium nanoparticles size are determined. The catalytic activity of the membranes is verified with the reduction of a nitro-compound and with a liquid phase Suzuki-Miyaura coupling reaction. Very low reaction times are observed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Fouling-induced enzyme immobilization for membrane reactors

    DEFF Research Database (Denmark)

    Luo, Jianquan; Meyer, Anne S.; Jonsson, Gunnar Eigil

    2013-01-01

    A simple enzyme immobilization method accomplished by promoting membrane fouling formation is proposed. The immobilization method is based on adsorption and entrapment of the enzymes in/on the membrane. To evaluate the concept, two membrane orientations, skin layer facing feed (normal mode......, but the reverse mode allowed for higher enzyme loading and stability, and irreversible fouling (i.e. pore blocking) developed more readily in the support structure than in the skin layer. Compared with an enzymatic membrane reactor (EMR) with free enzymes, the novel EMR with enzymes immobilized in membrane......) and support layer facing feed (reverse mode), were used to immobilize alcohol dehydrogenase (ADH, EC 1.1.1.1) and glutamate dehydrogenase (GDH, EC 1.4.1.3), respectively. The nature of the fouling in each mode was determined by filtration fouling models. The permeate flux was larger in the normal mode...

  9. Gauge/gravity duality for interactions of spherical membranes in 11-dimensional pp-wave

    International Nuclear Information System (INIS)

    Lee, Hok Kong; McLoughlin, Tristan; Wu Xinkai

    2005-01-01

    We investigate the gauge/gravity duality in the interaction between two spherical membranes in the 11-dimensional pp-wave background. On the supergravity side, we find the solution to the field equations at locations close to a spherical source membrane, and use it to obtain the light-cone Lagrangian of a spherical probe membrane very close to the source, i.e., with their separation much smaller than their radii. On the gauge theory side, using the BMN matrix model, we compute the one-loop effective potential between two membrane fuzzy spheres. Perfect agreement is found between the two sides. Moreover, the one-loop effective potential we obtain on the gauge theory side is valid beyond the small-separation approximation, giving the full interpolation between interactions of membrane-like objects and that of graviton-like objects

  10. Glycerol and urea can be used to increase skin permeability in reduced hydration conditions.

    Science.gov (United States)

    Björklund, Sebastian; Engblom, Johan; Thuresson, Krister; Sparr, Emma

    2013-12-18

    The natural moisturizing factor (NMF) is a group of hygroscopic molecules that is naturally present in skin and protects from severe drying. Glycerol and urea are two examples of NMF components that are also used in skin care applications. In the present study, we investigate the influence of glycerol and urea on the permeability of a model drug (metronidazole, Mz) across excised pig skin membranes at different hydrating conditions. The degree of skin hydration is regulated by the gradient in water activity across the membrane, which in turn depends on the water activity of the formulation in contact with the skin membrane. Here, we determine the water activity of all formulations employed using an isothermal calorimetric method. Thus, the gradient in water activity is controlled by a novel experimental set-up with well-defined boundary conditions on both sides of the skin membrane. The results demonstrate that glycerol and urea can retain high steady state flux of Mz across skin membranes at dehydrating conditions, which otherwise would decrease the permeability due to dehydration. X-ray diffraction measurements are performed to give insight into the effects of glycerol and urea on SC molecular organization. The novel steady state flux results can be related to the observation that water, glycerol, and urea all affect the structural features of the SC molecular components in a similar manner. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  11. Chondroitin-6-sulfate-containing proteoglycan: a new component of human skin dermoepidermal junction

    DEFF Research Database (Denmark)

    Fine, J D; Couchman, J R

    1988-01-01

    chondroitin sulfate proteoglycan is present in adult, neonatal, and/or fetal skin, and if present, its ultrastructural localization. Indirect immunofluorescence was performed on human adult, neonatal, and fetal skin. To detect the antigen, specimens were pretreated with chondroitinase ABC; absence of enzyme...... treatment served as negative control. Chondroitin sulfate proteoglycan was detectable in linear homogeneous array along the dermoepidermal junction and within vascular (and when present, adnexal) basement membranes in both adult and neonatal skin. In fetal skin, basement membrane staining was noted as early...... as 54 gestational days. Indirect immunoelectron microscopy and NaCl-split skin studies were performed to ultrastructurally localize the antigen; immune deposits were detectable within the lamina densa in chondroitinase-treated skin. These findings demonstrate that chondroitin sulfate proteoglycan...

  12. Skin-Sparing Radiation Using Intensity-Modulated Radiotherapy After Conservative Surgery in Early-Stage Breast Cancer: A Planning Study

    International Nuclear Information System (INIS)

    Saibishkumar, Elantholi P.; MacKenzie, Marc A.; Severin, Diane; Mihai, Alina; Hanson, John M.Sc.; Daly, Helene; Fallone, Gino; Parliament, Matthew B.; Abdulkarim, Bassam S.

    2008-01-01

    Purpose: To evaluate the feasibility of skin-sparing by configuring it as an organ-at-risk (OAR) while delivering whole-breast intensity-modulated radiotherapy (IMRT) in early breast cancer. Methods and Materials: Archival computed tomography scan images of 14 left-sided early-breast tumor patients who had undergone lumpectomy were selected for this study. Skin was contoured as a 4- to 5-mm strip extending from the patient outline to anterior margin of the breast planning target volume (PTV). Two IMRT plans were generated by the helical tomotherapy approach to deliver 50 Gy in 25 fractions to the breast alone: one with skin dose constraints (skin-sparing plan) and the other without (non-skin-sparing plan). Comparison of the plans was done using a two-sided paired Student t test. Results: The mean skin dose and volume of skin receiving 50 Gy were significantly less with the skin-sparing plan compared with non-skin-sparing plan (42.3 Gy vs. 47.7 Gy and 12.2% vs. 57.8% respectively; p < 0.001). The reduction in skin dose was confirmed by TLD measurements in anthropomorphic phantom using the same plans. Dose-volume analyses for other OARs were similar in both plans. Conclusions: By configuring the skin as an OAR, it is possible to achieve skin dose reduction while delivering whole-breast IMRT without compromising dose profiles to PTV and OARs

  13. Skin Diseases: Skin and Sun—Not a good mix

    Science.gov (United States)

    Skip Navigation Bar Home Current Issue Past Issues Skin Diseases Skin and Sun —Not a good mix Past Issues / ... of this page please turn Javascript on. Good skin care begins with sun safety. Whether it is ...

  14. Skin tribology: Science friction?

    NARCIS (Netherlands)

    van der Heide, Emile; Zeng, Xiangqiong; Masen, Marc Arthur

    2013-01-01

    The application of tribological knowledge is not just restricted to optimizing mechanical and chemical engineering problems. In fact, effective solutions to friction and wear related questions can be found in our everyday life. An important part is related to skin tribology, as the human skin is

  15. Examine Your Skin

    Medline Plus

    Full Text Available ... Facebook Twitter Newsletter Examine Your Skin Watch the video below and in only two minutes, you can learn to examine your skin. A special thanks to Dr. Martin Weinstock, MD, PhD, Professor of Dermatology, Brown University, for permission to use this video. UPDATED: ... Melanoma Facts Melanoma Prevention ...

  16. Bionanomaterials for skin regeneration

    CERN Document Server

    Leonida, Mihaela D

    2016-01-01

    This book gives a concise overview of bionanomaterials with applications for skin regeneration. The advantages and challenges of nanoscale materials are covered in detail, giving a basic view of the skin structure and conditions that require transdermal or topical applications. Medical applications, such as wound healing, care for burns, skin disease, and cosmetic care, such as aging of the skin and photodamage, and how they benefit from bionanomaterials, are described in detail. A final chapter is devoted to the ethical and social issues related to the use of bionanomaterials for skin regeneration. This is an ideal book for researchers in materials science, medical scientists specialized in dermatology, and cosmetic chemists working in formulations. It can also serve as a reference for nanotechnologists, dermatologists, microbiologists, engineers, and polymer chemists, as well as students studying in these fields.

  17. Preparation of membranes from cellulose obtained of sugarcane bagasse

    International Nuclear Information System (INIS)

    Pereira, Paulo Henrique Fernandes; Cioffi, Maria Odila Hilario; Voorwald, Herman Jacobus Cornelis; Pinho, Maria Noberta de; Silva, Maria Lucia Caetano Pinto da

    2010-01-01

    In this work, cellulose obtained from sugarcane bagasse to produce both cellulose and acetylated cellulose to prepare asymmetric membranes. Membranes was procedure used a mixture of materials of DMAc/ LiCl systemic in different conditions. Cellulose and acetylated cellulose were characterized by thermogravimetric (TG), Xray diffraction (XRD) and scanning Electron Microscopy (SEM). Observed less stability thermal of acetylated cellulose when compared of cellulose. All membranes procedure were asymmetric, characterized by presence of a dense skin and porous support can be observed. SEM showed that the morphology of the superficial of membranes depends on the method preparation. (author)

  18. The Relative Utility of Skin Resistance and Skin Conductance

    National Research Council Canada - National Science Library

    Barland, Gordon

    1990-01-01

    The effectiveness of two circuits (constant current = skin resistance; constant voltage = skin conductance) used for measuring electrodermal activity during a psychophysiological detection of deception...

  19. Dry skin - self-care

    Science.gov (United States)

    ... pat skin dry then apply your moisturizer. Avoid skin care products and soaps that contain alcohol, fragrances, dyes, or other chemicals. Take short, warm baths or showers. Limit your ... gentle skin cleansers or soap with added moisturizers. Only use ...

  20. 6 Common Cancers - Skin Cancer

    Science.gov (United States)

    ... Bar Home Current Issue Past Issues 6 Common Cancers - Skin Cancer Past Issues / Spring 2007 Table of Contents ... AP Photo/Herald-Mail, Kevin G. Gilbert Skin Cancer Skin cancer is the most common form of cancer ...

  1. Cryogen therapy of skin cancer

    International Nuclear Information System (INIS)

    Zikiryakhodjaev, D.Z.; Sanginov, D.R.

    2001-01-01

    In this chapter authors studied the cure of skin cancer in particular cryogen therapy of skin cancer. They noted that cryogen therapy of skin cancer carried new possibilities and improved results of neoplasms treatment

  2. Robotic membranes

    DEFF Research Database (Denmark)

    Ramsgaard Thomsen, Mette

    2008-01-01

    The relationship between digital and analogue is often constructed as one of opposition. The perception that the world is permeated with underlying patterns of data, describing events and matter alike, suggests that information can be understood apart from the substance to which it is associated......, and that its encoded logic can be constructed and reconfigured as an isolated entity. This disembodiment of information from materiality implies that an event like a thunderstorm, or a material like a body, can be described equally by data, in other words it can be read or written. The following prototypes......, Vivisection and Strange Metabolisms, were developed at the Centre for Information Technology and Architecture (CITA) at the Royal Danish Academy of Fine Arts in Copenhagen as a means of engaging intangible digital data with tactile physical material. As robotic membranes, they are a dual examination...

  3. Deformation of Two-Dimensional Nonuniform-Membrane Red Blood Cells Simulated by a Lattice Boltzmann Model

    International Nuclear Information System (INIS)

    Hua-Bing, Li; Li, Jin; Bing, Qiu

    2008-01-01

    To study two-dimensional red blood cells deforming in a shear Bow with the membrane nonuniform on the rigidity and mass, the membrane is discretized into equilength segments. The fluid inside and outside the red blood cell is simulated by the D2Q9 lattice Boltzmann model and the hydrodynamic forces exerted on the membrane from the inner and outer of the red blood cell are calculated by a stress-integration method. Through the global deviation from the curvature of uniform-membrane, we find that when the membrane is nonuniform on the rigidity, the deviation first decreases with the time increases and implies that the terminal profile of the red blood cell is static. To a red blood cell with the mass nonuniform on the membrane, the deviation becomes more large, and the mass distribution affects the profile of the two sides of the flattened red blood cell in a shear flow. (fundamental areas of phenomenology(including applications))

  4. Skin and antioxidants.

    Science.gov (United States)

    Poljsak, Borut; Dahmane, Raja; Godic, Aleksandar

    2013-04-01

    It is estimated that total sun exposure occurs non-intentionally in three quarters of our lifetimes. Our skin is exposed to majority of UV radiation during outdoor activities, e.g. walking, practicing sports, running, hiking, etc. and not when we are intentionally exposed to the sun on the beach. We rarely use sunscreens during those activities, or at least not as much and as regular as we should and are commonly prone to acute and chronic sun damage of the skin. The only protection of our skin is endogenous (synthesis of melanin and enzymatic antioxidants) and exogenous (antioxidants, which we consume from the food, like vitamins A, C, E, etc.). UV-induced photoaging of the skin becomes clinically evident with age, when endogenous antioxidative mechanisms and repair processes are not effective any more and actinic damage to the skin prevails. At this point it would be reasonable to ingest additional antioxidants and/or to apply them on the skin in topical preparations. We review endogenous and exogenous skin protection with antioxidants.

  5. Occupational skin cancers

    Energy Technology Data Exchange (ETDEWEB)

    Gawkrodger, D.J. [Royal Hallamshire Hospital, Sheffield (United Kingdom). Dept. of Dermatology

    2004-10-01

    Skin cancer due to occupation is more common than is generally recognized, although it is difficult to obtain an accurate estimate of its prevalence. Over the past two centuries, occupational skin cancers have particularly been due to industrial exposure of men (it seems more so than women) to chemical carcinogens such as polycyclic hydrocarbons (e.g. from coal tar products) or to arsenic. Industrial processes have improved in most Western countries to limit this type of exposure, but those with outdoor occupations are still exposed to solar ultraviolet irradiation without this being widely recognized as an industrial hazard. Ionizing radiation such as X-rays can also cause skin cancer. Occupational skin cancers often resemble skin tumours found in non-occupational subjects, e.g. basal cell carcinoma, squamous cell carcinoma and malignant melanoma, but some pre-malignant lesions can be more specific and point to an occupational origin, e.g. tar keratoses or arsenical keratoses. An uncommon but well-recognized cause of occupational skin cancer is that which results from scar formation following an industrial burn. In the future it will be necessary to focus on preventative measures, e.g. for outdoor workers, the need to cover up in the sun and use sun protective creams and a campaign for earlier recognition of skin cancers, which are usually curable if treated in their early stages.

  6. Skin Picking Disorder

    Directory of Open Access Journals (Sweden)

    Pinar Cetinay Aydin

    2014-08-01

    Full Text Available Skin picking disorder is not a dermatological disorder and it is a table characterized with picking skin excessively and repetitively, leading to damage in skin tissue. Unlike normal picking behaviour, psychogenic skin picking is repetitive and it can lead to severe damage in the skin and even complications which constitute vital danger. While some patients define frequent but short lasting picking attacks, others define rarer attacks which last a few hours. Skin picking disorder, which is not included in the classification systems up to DSM-5 as a separate diagnosis category, is included as an independent diagnosis in Obsessive Compulsive Disorder and Associated Disorders category in DSM-5. In case reports, open label studies and double blind studies selective serotonin reuptake inhibitors are shown to be effective in the treatment of skin picking disorder. Mostly, cognitive-behaviourial techniques are used and have been proven to be useful in psychotherapy. Habit reversal is one of the behaviourial techniques which are frequently applied, give positive results in which well-being state can be maintained. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(4.000: 401-428

  7. Manifestações cutâneo-mucosas da coccidioidomicose: estudo de trinta casos procedentes dos estados do Piauí e Maranhão Skin and mucous membrane manifestations of coccidioidomycosis: a study of thirty cases in the Brazilian states of Piauí and Maranhão

    Directory of Open Access Journals (Sweden)

    Antônio de Deus Filho

    2010-02-01

    Full Text Available FUNDAMENTOS: A coccidioidomicose é micose sistêmica usualmente manifesta como infecção benigna de resolução espontânea; porém, uma pequena proporção dos infectados desenvolve quadros progressivos potencialmente fatais, podendo atingir a pele com lesões pleomórficas disseminadas. OBJETIVOS: Identificar e descrever as manifestações cutâneo-mucosas da coccidioidomicose, as ocupações de risco relacionadas à doença e o quadro clínico associado. MÉTODOS: Estudo realizado entre os anos 2003 e 2006 em 30 pacientes portadores de coccidioidomicose provenientes dos estados do Piauí e Maranhão e diagnosticados por exame microscópico direto, cultivo do escarro ou sorologia de triagem de imunodifusão dupla em gel de ágar, aliados à anamnese e exame físico. RESULTADOS: Identificaram-se lesões extrapulmonares em 13 casos (43,3%, com predomínio de manifestações dermatológicas de hipersensibilidade: eritema nodoso (26,6%, exantema com lesões eritemato-escamosas (26,6% e eritema multiforme (23,3%, além de úlceras de língua (13,3% e lábio (6,6% e abscesso subcutâneo (3,3%. Tais manifestações foram observadas na fase aguda da doença. CONCLUSÕES: As manifestações cutâneas associadas à infecção respiratória aguda fortalecem a hipótese diagnóstica desta doença, especialmente, em caçadores de tatus ou pessoas expostas à escavação do solo.BACKGROUND: Coccidioidomycosis is a systemic mycosis that usually presents as a benign infection. Patients generally recover spontaneously; however, a small proportion of infected individuals develop progressive complications that may affect the skin in the form of disseminated pleomorphic lesions and may become fatal. OBJECTIVES: To identify and describe skin and mucous membrane manifestations of coccidioidomycosis, to identify occupational hazards associated with the disease and to determine its associated clinical presentation. METHODS: A study conducted between 2003 and 2006

  8. Toxic effects of ultraviolet radiation on the skin

    International Nuclear Information System (INIS)

    Matsumura, Yasuhiro; Ananthaswamy, Honnavara N.

    2004-01-01

    Ultraviolet (UV) irradiation present in sunlight is an environmental human carcinogen. The toxic effects of UV from natural sunlight and therapeutic artificial lamps are a major concern for human health. The major acute effects of UV irradiation on normal human skin comprise sunburn inflammation (erythema), tanning, and local or systemic immunosuppression. At the molecular level, UV irradiation causes DNA damage such as cyclobutane pyrimidine dimers and (6-4) photoproducts, which are usually repaired by nucleotide excision repair (NER). Chronic exposure to UV irradiation leads to photoaging, immunosuppression, and ultimately photocarcinogenesis. Photocarcinogenesis involves the accumulation of genetic changes, as well as immune system modulation, and ultimately leads to the development of skin cancers. In the clinic, artificial lamps emitting UVB (280-320 nm) and UVA (320-400 nm) radiation in combination with chemical drugs are used in the therapy of many skin diseases including psoriasis and vitiligo. Although such therapy is beneficial, it is accompanied with undesirable side effects. Thus, UV radiation is like two sides of the same coin--on one side, it has detrimental effects, and on the other side, it has beneficial effects

  9. Dermal-epidermal membrane systems by using human keratinocytes and mesenchymal stem cells isolated from dermis

    Energy Technology Data Exchange (ETDEWEB)

    Salerno, Simona, E-mail: s.salerno@itm.cnr.it [Institute on Membrane Technology, National Research Council of Italy, ITM-CNR, c/o University of Calabria, via P. Bucci cubo 17/C, I-87036, Rende (CS) (Italy); Messina, Antonietta [Institute on Membrane Technology, National Research Council of Italy, ITM-CNR, c/o University of Calabria, via P. Bucci cubo 17/C, I-87036, Rende (CS) (Italy); Giordano, Francesca [Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, I-87036 Rende, (CS) (Italy); Bader, Augustinus [Biomedical-Biotechnological Center, BBZ, University of Leipzig, D-04103 Leipzig (Germany); Drioli, Enrico [Institute on Membrane Technology, National Research Council of Italy, ITM-CNR, c/o University of Calabria, via P. Bucci cubo 17/C, I-87036, Rende (CS) (Italy); WCU Energy Engineering Department, Hanyang University, Seoul (Korea, Republic of); De Bartolo, Loredana, E-mail: l.debartolo@itm.cnr.it [Institute on Membrane Technology, National Research Council of Italy, ITM-CNR, c/o University of Calabria, via P. Bucci cubo 17/C, I-87036, Rende (CS) (Italy)

    2017-02-01

    Dermal-epidermal membrane systems were developed by co-culturing human keratinocytes with Skin derived Stem Cells (SSCs), which are Mesenchymal Stem Cells (MSCs) isolated from dermis, on biodegradable membranes of chitosan (CHT), polycaprolactone (PCL) and a polymeric blend of CHT and PCL. The membranes display physico-chemical, morphological, mechanical and biodegradation properties that could satisfy and fulfil specific requirements in skin tissue engineering. CHT membrane exhibits an optimal biodegradation rate for acute wounds; CHT-PCL for the chronic ones. On the other hand, PCL membrane in spite of its very slow biodegradation rate exhibits mechanical properties similar to in vivo dermis, a lower hydrophilic character, and a surface roughness, all properties that make it able to sustain cell adhesion and proliferation for in vitro skin models. Both CHT–PCL and PCL membranes guided epidermal and dermal differentiation of SSCs as pointed out by the expression of cytokeratins and the deposition of the ECM protein fibronectin, respectively. In the dermal-epidermal membrane systems, a more suitable microenvironment for the SSCs differentiation was promoted by the interactions and the mutual interplay with keratinocytes. Being skin tissue-biased stem cells committed to their specific final dermal and/or epidermal cell differentiation, SSCs are more suitable for skin tissue engineering than other adult MSCs with different origin. For this reason, they represent a useful autologous cell source for engineering skin substitutes for both in vivo and in vitro applications.

  10. Ultrasound skin tightening.

    Science.gov (United States)

    Minkis, Kira; Alam, Murad

    2014-01-01

    Ultrasound skin tightening is a noninvasive, nonablative method that allows for energy deposition into the deep dermal and subcutaneous tissue while avoiding epidermal heating. Ultrasound coagulation is confined to arrays of 1-mm(3) zones that include the superficial musculoaponeurotic system and connective tissue. This technology gained approval from the Food and Drug Administration as the first energy-based skin "lifting" device, specifically for lifting lax tissue on the neck, submentum, and eyebrows. Ultrasound has the unique advantage of direct visualization of treated structures during treatment. Ultrasound is a safe and efficacious treatment for mild skin tightening and lifting. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Modelling the effect of mixture components on permeation through skin.

    Science.gov (United States)

    Ghafourian, T; Samaras, E G; Brooks, J D; Riviere, J E

    2010-10-15

    A vehicle influences the concentration of penetrant within the membrane, affecting its diffusivity in the skin and rate of transport. Despite the huge amount of effort made for the understanding and modelling of the skin absorption of chemicals, a reliable estimation of the skin penetration potential from formulations remains a challenging objective. In this investigation, quantitative structure-activity relationship (QSAR) was employed to relate the skin permeation of compounds to the chemical properties of the mixture ingredients and the molecular structures of the penetrants. The skin permeability dataset consisted of permeability coefficients of 12 different penetrants each blended in 24 different solvent mixtures measured from finite-dose diffusion cell studies using porcine skin. Stepwise regression analysis resulted in a QSAR employing two penetrant descriptors and one solvent property. The penetrant descriptors were octanol/water partition coefficient, logP and the ninth order path molecular connectivity index, and the solvent property was the difference between boiling and melting points. The negative relationship between skin permeability coefficient and logP was attributed to the fact that most of the drugs in this particular dataset are extremely lipophilic in comparison with the compounds in the common skin permeability datasets used in QSAR. The findings show that compounds formulated in vehicles with small boiling and melting point gaps will be expected to have higher permeation through skin. The QSAR was validated internally, using a leave-many-out procedure, giving a mean absolute error of 0.396. The chemical space of the dataset was compared with that of the known skin permeability datasets and gaps were identified for future skin permeability measurements. Copyright 2010 Elsevier B.V. All rights reserved.

  12. Three-Dimensional In Vitro Skin and Skin Cancer Models Based on Human Fibroblast-Derived Matrix.

    Science.gov (United States)

    Berning, Manuel; Prätzel-Wunder, Silke; Bickenbach, Jackie R; Boukamp, Petra

    2015-09-01

    Three-dimensional in vitro skin and skin cancer models help to dissect epidermal-dermal and tumor-stroma interactions. In the model presented here, normal human dermal fibroblasts isolated from adult skin self-assembled into dermal equivalents with their specific fibroblast-derived matrix (fdmDE) over 4 weeks. The fdmDE represented a complex human extracellular matrix that was stabilized by its own heterogeneous collagen fiber meshwork, largely resembling a human dermal in vivo architecture. Complemented with normal human epidermal keratinocytes, the skin equivalent (fdmSE) thereof favored the establishment of a well-stratified and differentiated epidermis and importantly allowed epidermal regeneration in vitro for at least 24 weeks. Moreover, the fdmDE could be used to study the features of cutaneous skin cancer. Complementing fdmDE with HaCaT cells in different stages of malignancy or tumor-derived cutaneous squamous cell carcinoma cell lines, the resulting skin cancer equivalents (fdmSCEs) recapitulated the respective degree of tumorigenicity. In addition, the fdmSCE invasion phenotypes correlated with their individual degree of tissue organization, disturbance in basement membrane organization, and presence of matrix metalloproteinases. Together, fdmDE-based models are well suited for long-term regeneration of normal human epidermis and, as they recapitulate tumor-specific growth, differentiation, and invasion profiles of cutaneous skin cancer cells, also provide an excellent human in vitro skin cancer model.

  13. Spiritual and religious aspects of skin and skin disorders

    Directory of Open Access Journals (Sweden)

    Shenefelt PD

    2014-08-01

    Full Text Available Philip D Shenefelt,1 Debrah A Shenefelt2 1Dermatology and Cutaneous Surgery, University of South Florida, Tampa, 2Congregation Or Ahavah, Lutz, FL, USA Abstract: Skin and skin disorders have had spiritual aspects since ancient times. Skin, hair, and nails are visible to self and others, and touchable by self and others. The skin is a major sensory organ. Skin also expresses emotions detectable by others through pallor, coldness, "goose bumps", redness, warmth, or sweating. Spiritual and religious significances of skin are revealed through how much of the skin has been and continues to be covered with what types of coverings, scalp and beard hair cutting, shaving and styling, skin, nail, and hair coloring and decorating, tattooing, and intentional scarring of skin. Persons with visible skin disorders have often been stigmatized or even treated as outcasts. Shamans and other spiritual and religious healers have brought about healing of skin disorders through spiritual means. Spiritual and religious interactions with various skin disorders such as psoriasis, leprosy, and vitiligo are discussed. Religious aspects of skin and skin diseases are evaluated for several major religions, with a special focus on Judaism, both conventional and kabbalistic. Keywords: skin, skin disorders, spiritual, religious

  14. Skin Diseases: Cross-section of human skin

    Science.gov (United States)

    Skip Navigation Bar Home Current Issue Past Issues Skin Diseases Cross-section of human skin Past Issues / Fall 2008 Table of Contents For ... Logical Images, Inc. I n the areas of skin health and skin diseases, the NIH's National Institute ...

  15. Cure of skin cancer. Surgical cure of skin cancer

    International Nuclear Information System (INIS)

    Zikiryakhodjaev, D.Z.; Sanginov, D.R.

    2001-01-01

    In this chapter authors studied the cure of skin cancer in particular the surgical cure of skin cancer. They noted that surgical cure of skin cancer is remain one of the primary and most important methods in treatment of skin cancer

  16. Artificial skin and patient simulator comprising the artificial skin

    NARCIS (Netherlands)

    2011-01-01

    The invention relates to an artificial skin (10, 12, 14), and relates to a patient simulator (100) comprising the artificial skin. The artificial skin is a layered structure comprising a translucent cover layer (20) configured for imitating human or animal skin, and comprising a light emitting layer

  17. Allergy Skin Tests

    Science.gov (United States)

    ... and symptoms. Medications can interfere with results Before scheduling a skin test, bring your doctor a list ... of Privacy Practices Notice of Nondiscrimination Manage Cookies Advertising Mayo Clinic is a not-for-profit organization ...

  18. Caring for Tattooed Skin

    Science.gov (United States)

    ... Registration General information Housing & travel Education Exhibit hall Mobile app 2019 Annual Meeting Derm Exam Prep Course ... SkinPAC State societies Scope of practice Truth in advertising NP/PA laws Action center Public and patients ...

  19. Dry Skin (Xerosis)

    Science.gov (United States)

    ... Registration General information Housing & travel Education Exhibit hall Mobile app 2019 Annual Meeting Derm Exam Prep Course ... SkinPAC State societies Scope of practice Truth in advertising NP/PA laws Action center Public and patients ...

  20. Impairments in Skin Integrity.

    Science.gov (United States)

    Murphree, Rose W

    2017-09-01

    Altered skin integrity increases the chance of infection, impaired mobility, and decreased function and may result in the loss of limb or, sometimes, life. Skin is affected by both intrinsic and extrinsic factors. Intrinsic factors can include altered nutritional status, vascular disease issues, and diabetes. Extrinsic factors include falls, accidents, pressure, immobility, and surgical procedures. Ensuring skin integrity in the elderly requires a team approach and includes the individual, caregivers, and clinicians. The twenty-first century clinician has several online, evidence-based tools to assist with optimal treatment plans. Understanding best practices in addressing skin integrity issues can promote positive outcomes with the elderly. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Allergy testing - skin

    Science.gov (United States)

    Patch tests - allergy; Scratch tests - allergy; Skin tests - allergy; RAST test; Allergic rhinitis - allergy testing; Asthma - allergy testing; Eczema - allergy testing; Hayfever - allergy testing; Dermatitis - allergy testing; Allergy testing; ...

  2. Examine Your Skin

    Medline Plus

    Full Text Available ... Store In Memory Melanoma Info Melanoma Facts Melanoma Prevention Sunscreen Suggestions Examine Your Skin Newly Diagnosed? Understanding ... Biopsy: The First Step Sentinel Node Biopsy Melanoma Treatment: Stages I & II Melanoma Treatment: Stage III Melanoma ...

  3. Examine Your Skin

    Medline Plus

    Full Text Available ... We Are Be On Our PAGE MIF Staff Programs & Services Scientific Advisory Board Advisory Board Patrons & Sponsors ... us for One-on-One Support Donate Share Facebook Twitter Newsletter Examine Your Skin Watch the video ...

  4. Occupational skin diseases

    DEFF Research Database (Denmark)

    Mahler, V; Aalto-Korte, K; Alfonso, J H

    2017-01-01

    BACKGROUND: Work-related skin diseases (WSD) are caused or worsened by a professional activity. Occupational skin diseases (OSD) need to fulfil additional legal criteria which differ from country to country. OSD range amongst the five most frequently notified occupational diseases (musculoskeletal...... diseases, neurologic diseases, lung diseases, diseases of the sensory organs, skin diseases) in Europe. OBJECTIVE: To retrieve information and compare the current state of national frameworks and pathways to manage patients with occupational skin disease with regard to prevention, diagnosis, treatment...... in Science and Technology (COST) Action TD 1206 (StanDerm) (www.standerm.eu). RESULTS: Besides a national health service or a statutory health insurance, most European member states implemented a second insurance scheme specifically geared at occupational diseases [insurance against occupational risks...

  5. Skin care and incontinence

    Science.gov (United States)

    ... skin care; Incontinence - pressure sore; Incontinence - pressure ulcer Patient Instructions Preventing pressure ulcers Images Male urinary system References Holroyd S. Incontinence-associated dermatitis: identification, prevention and care. Br J Nurs . 2015;24( ...

  6. Healthy Skin Matters

    Science.gov (United States)

    ... skin. If you’re helping out in the kitchen, make sure you use hot pads or wear ... in humans, plants, and animals, while others are essential for a healthy life. Propionibacterium acnes (P. acnes) ( ...

  7. Tuberculin Skin Testing

    Science.gov (United States)

    ... Appendix 1 Appendix 2 Appendix 3 Interim Laboratory Biosafety Guidance for XDR Mycobacterium tuberculosis strains Data & Statistics ... The Mantoux tuberculin skin test (TST) is the standard method of determining whether a person is infected ...

  8. [Currently available skin substitutes].

    Science.gov (United States)

    Oravcová, Darina; Koller, Ján

    2014-01-01

    The current trend of burn wound care has shifted to more holistic approach of improvement in the long-term form and function of the healed burn wounds and quality of life. Autologous split or full-thickness skin graft are the best definitive burn wound coverage, but it is constrained by the limited available sources, especially in major burns. Donor site morbidities in term of additional wounds and scarring are also of concern of the autograft application. This has demanded the emergence of various skin substitutes in the management of acute burn injury as well as post burn reconstructions. This paper reviews currently available skin substitutes, produced in not for-profit skin banks as well as commercially available. They are divided according to type of material included, as biological, biosynthetic and synthetic and named respectively.

  9. Parasites and the skin

    African Journals Online (AJOL)

    2009-06-11

    Jun 11, 2009 ... those conditions that are encountered in daily practice and to remind you of those ... care conditions. Parasitic infections can be solely confined to the skin, as seen ..... endemic areas or may become chronic and disseminate.

  10. Skin or nail culture

    Science.gov (United States)

    Mucosal culture; Culture - skin; Culture - mucosal; Nail culture; Culture - fingernail; Fingernail culture ... There, it is placed in a special dish (culture). It is then watched to see if bacteria, ...

  11. Fungal Skin Infections

    Science.gov (United States)

    ... Abbreviations Weights & Measures ENGLISH View Professional English Deutsch Japanese Espaniol Find information on medical topics, symptoms, drugs, ... touching the infected area. Diagnosis Skin scrapings or cultures Doctors may suspect a fungal infection when they ...

  12. Examine Your Skin

    Medline Plus

    Full Text Available ... Download a Skin Self-Exam Card Download a Patient Navigation Card Events, Webinars & Videos Events, Webinars & Videos Melanoma Patient Video Events Host an Event Past Webinars Upcoming ...

  13. Allergic Skin Conditions

    Science.gov (United States)

    ... most common types are atopic dermatitis (often called eczema) and contact dermatitis. Atopic Dermatitis (Eczema) Eczema is a chronic ... contact with your skin, they may cause a rash called contact dermatitis. There are two kinds of contact dermatitis: ...

  14. Neuromodulators for Aging Skin

    Science.gov (United States)

    ... Light treatment to the skin and Restylane to tear troughs and outer eyebrow. Photo courtesy of Rebecca Fitzagerald, MD - Los Angeles, California Possible risks Soreness Mild bruising Temporary weakness of surrounding muscles Headache Drooping eyelid Why choose neuromodulators for aging ...

  15. Examine Your Skin

    Medline Plus

    Full Text Available ... Doctor Glossary of Terms Resources Resources Global Resources Cancer Centers Online Resources The Melanoma Book Clinical Trials Download a Skin Self-Exam Card Download a Patient Navigation Card ...

  16. ReciPlySkin

    DEFF Research Database (Denmark)

    Popovic Larsen, Olga; Andersen, Mikkel; Munk-Andersen, Niklas

    2017-01-01

    The report presents process that enbabled the production of the ReciPlySkin structure exhibited at the Circular Economy Exhibition at KADK during the Autumn 2017. The concept, design, detailed design and production are presented in this report.......The report presents process that enbabled the production of the ReciPlySkin structure exhibited at the Circular Economy Exhibition at KADK during the Autumn 2017. The concept, design, detailed design and production are presented in this report....

  17. Adnexal Tumours Of Skin

    Directory of Open Access Journals (Sweden)

    Parate Sanjay N

    1998-01-01

    Full Text Available A total 120 cases of epidermal appendage tumours of skin were analysed and classified according to the classification provided by WHO’. Epidermal appendage tumours accounted for 12.87% of all skin tumours, of which 29.17% were benign and 70.83% were malignant. Most of the tumours (75.83% were in the head and face region. The most common tumour was basal cell epithelioma (55%.

  18. Mantoux Tuberculin Skin Test

    Centers for Disease Control (CDC) Podcasts

    2006-11-22

    Learn how to evaluate people for latent TB infection with the Mantoux tuberculin skin test. This podcast includes sections on administering and reading the Mantoux tuberculin skin test, the standard method for detecting latent TB infection since the 1930s.  Created: 11/22/2006 by National Center for HIV, STD and TB Prevention (NCHHSTP).   Date Released: 12/12/2006.

  19. Stressed skin panels

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2001-07-01

    Advantages and disadvantages of stressed skin panels, also known as structural insulated panels (SIPs), are discussed as material and labour-saving alternatives to traditional stick framing. Stressed skin panels are manufactured 'sandwich' assemblies with a rigid insulating polystyrene foam core, whose interior and exterior surfaces are bonded into panels. The skins distribute and carry the structural loading while the bonded foam core provides insulation and keeps the two skins aligned. Since there are fewer framing members, there is little thermal bridging and the R-value remains high. SIPs are usually manufactured in four feet by eight feet panels, although some manufacturers can produce panels up to eight feet by forty feet. SIPs are resource efficient as they use less wood than conventional framing (about 25 per cent less); can structurally cover large spans, requiring less supplementary framing. Use of SIPs eliminate the need for headers over small openings; provide the ability to nail anywhere; create less scrap and waste; lessen vulnerability to unfavourable weather and other job-site hazards, can reduce delays, and often can produce significant savings in material and labour costs. Limitations include the more complex approaches to plumbing and electrical systems, although this can be minimized by designers by incorporating much of the plumbing and electrical work on interior (non-panel) walls. Most stressed skin panels require one-half inch interior gypsum drywall. If become wet, stressed skin panels take a long time to dry out and may harbour mold growth. Larger stressed-skin panels used in floors and roofs, may require cranes or other machinery for handling because of their weight. Although not without some environmental impact, overall, stressed skin panels are judged to be a resource-efficient building technology with significant energy-efficiency benefits and distinct advantages over stick framing. 3 photos.

  20. The asymmetric facial skin perfusion distribution of Bell's palsy discovered by laser speckle imaging technology.

    Science.gov (United States)

    Cui, Han; Chen, Yi; Zhong, Weizheng; Yu, Haibo; Li, Zhifeng; He, Yuhai; Yu, Wenlong; Jin, Lei

    2016-01-01

    Bell's palsy is a kind of peripheral neural disease that cause abrupt onset of unilateral facial weakness. In the pathologic study, it was evidenced that ischemia of facial nerve at the affected side of face existed in Bell's palsy patients. Since the direction of facial nerve blood flow is primarily proximal to distal, facial skin microcirculation would also be affected after the onset of Bell's palsy. Therefore, monitoring the full area of facial skin microcirculation would help to identify the condition of Bell's palsy patients. In this study, a non-invasive, real time and full field imaging technology - laser speckle imaging (LSI) technology was applied for measuring facial skin blood perfusion distribution of Bell's palsy patients. 85 participants with different stage of Bell's palsy were included. Results showed that Bell's palsy patients' facial skin perfusion of affected side was lower than that of the normal side at the region of eyelid, and that the asymmetric distribution of the facial skin perfusion between two sides of eyelid is positively related to the stage of the disease (P Bell's palsy patients, and we discovered that the facial skin blood perfusion could reflect the stage of Bell's palsy, which suggested that microcirculation should be investigated in patients with this neurological deficit. It was also suggested LSI as potential diagnostic tool for Bell's palsy.

  1. Intrinsic potential of cell membranes: opposite effects of lipid transmembrane asymmetry and asymmetric salt ion distribution

    DEFF Research Database (Denmark)

    Gurtovenko, Andrey A; Vattulainen, Ilpo

    2009-01-01

    Using atomic-scale molecular dynamics simulations, we consider the intrinsic cell membrane potential that is found to originate from a subtle interplay between lipid transmembrane asymmetry and the asymmetric distribution of monovalent salt ions on the two sides of the cell membrane. It turns out......Cl saline solution and the PE leaflet is exposed to KCl, the outcome is that the effects of asymmetric lipid and salt ion distributions essentially cancel one another almost completely. Overall, our study highlights the complex nature of the intrinsic potential of cell membranes under physiological...... that both the asymmetric distribution of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) lipids across a membrane and the asymmetric distribution of NaCl and KCl induce nonzero drops in the transmembrane potential. However, these potential drops are opposite in sign. As the PC leaflet faces a Na...

  2. Recent advances on polymeric membranes for membrane reactors

    KAUST Repository

    Buonomenna, M. G.; Choi, Seung Hak

    2012-01-01

    . The successful use of membranes in membrane reactors is primary the result of two developments concerning: (i) membrane materials and (ii) membrane structures. The selection of a suited material and preparation technique depends on the application the membrane

  3. Proof-of-concept: 3D bioprinting of pigmented human skin constructs.

    Science.gov (United States)

    Ng, Wei Long; Qi, Jovina Tan Zhi; Yeong, Wai Yee; Naing, May Win

    2018-01-23

    Three-dimensional (3D) pigmented human skin constructs have been fabricated using a 3D bioprinting approach. The 3D pigmented human skin constructs are obtained from using three different types of skin cells (keratinocytes, melanocytes and fibroblasts from three different skin donors) and they exhibit similar constitutive pigmentation (pale pigmentation) as the skin donors. A two-step drop-on-demand bioprinting strategy facilitates the deposition of cell droplets to emulate the epidermal melanin units (pre-defined patterning of keratinocytes and melanocytes at the desired positions) and manipulation of the microenvironment to fabricate 3D biomimetic hierarchical porous structures found in native skin tissue. The 3D bioprinted pigmented skin constructs are compared to the pigmented skin constructs fabricated by conventional a manual-casting approach; in-depth characterization of both the 3D pigmented skin constructs has indicated that the 3D bioprinted skin constructs have a higher degree of resemblance to native skin tissue in term of the presence of well-developed stratified epidermal layers and the presence of a continuous layer of basement membrane proteins as compared to the manually-cast samples. The 3D bioprinting approach facilitates the development of 3D in vitro pigmented human skin constructs for potential toxicology testing and fundamental cell biology research.

  4. Changes in Transepidermal Water Loss and Skin Hydration according to Expression of Aquaporin-3 in Psoriasis

    Science.gov (United States)

    Lee, Young; Je, Young-Jin; Lee, Sang-Sin; Li, Zheng Jun; Choi, Dae-Kyoung; Kwon, Yoo-Bin; Sohn, Kyung-Cheol; Im, Myung; Seo, Young Joon

    2012-01-01

    Background Aquaporins (AQPs) are a family of water transporting proteins present in many mammalian epithelial and endothelial cell types. Among the AQPs, AQP3 is known to be a water/glycerol transporter expressed in human skin. Objective The relationship between the expression level of AQP3 and transpidermal water loss (TEWL) in the lesional and peri-lesional skin of psoriasis-affected patients, and skin hydration in the lesional and peri-lesional skin of psoriasis patients, was investigated. Methods The expression of AQP3 in psoriasis-affected and healthy control skin was determined using immunohistochemical and immunofluroscence staining. TEWL and skin hydration were measured using a Tewameter® TM210 (Courage & Khazaka, Cologne, Germany) and a Corneometer® CM 820 (Courage & Khazaka), respectively. Results AQP3 was mainly expressed in the plasma membrane of stratum corneum and the stratum spinosum in normal epidermis. Unlike the normal epidermis, AQP3 showed decreased expression in the lesional and peri-lesional epidermis of psoriasis. TEWL was increased, and skin hydration was decreased, in the lesional and peri-lesional skin of psoriasis patients, compared with the healthy control sample. Conclusion Although various factors contribute to reduced skin hydration in the lesional and peri-lesional skin of psoriasis, AQP3 appears to be a key factor in the skin dehydration of psoriasis-affected skin. PMID:22577267

  5. Magnetically controlled permeability membranes

    KAUST Repository

    Kosel, Jurgen

    2013-10-31

    A bioactive material delivery system can include a thermoresponsive polymer membrane and nanowires distributed within the thermoresponsive polymer membrane. Magnetic activation of a thermoresponsive polymer membrane can take place via altering the magnetization or dimensions of nanowires dispersed or ordered within the membrane matrix.

  6. Magnetically controlled permeability membranes

    KAUST Repository

    Kosel, Jü rgen; Khashab, Niveen M.; Zaher, Amir

    2013-01-01

    A bioactive material delivery system can include a thermoresponsive polymer membrane and nanowires distributed within the thermoresponsive polymer membrane. Magnetic activation of a thermoresponsive polymer membrane can take place via altering the magnetization or dimensions of nanowires dispersed or ordered within the membrane matrix.

  7. Evaluation of nicotinamide microemulsion on the skin penetration enhancement.

    Science.gov (United States)

    Boonme, Prapaporn; Boonthongchuay, Chalida; Wongpoowarak, Wibul; Amnuaikit, Thanaporn

    2016-01-01

    This study purposed to evaluate a microemulsion containing nicotinamide for its characteristics, stability, and skin penetration and retention comparing with a solution of nicotinamide in 2:1 mixture of water and isopropyl alcohol (IPA). The microemulsion system was composed of 1:1 mixture of Span80 and Tween80 as a surfactant mixture, isopropyl palmitate (IPP) as an oil phase, and 2:1 mixture of water and IPA as an aqueous phase. Nicotinamide microemulsion was prepared by dissolving the active in the aqueous phase before simply mixing with the other components. It was determined for its characteristics and stability under various conditions. The skin penetration and retention studies of nicotinamide microemulsion and solution were performed by modified Franz diffusion cells, using newborn pig skin as the membrane. The results showed that nicotinamide microemulsion could be obtained as clear yellowish liquid, was water-in-oil (w/o) type, possessed Newtonian flow, and exhibited physicochemical stability when kept at 4 °C and room temperature (≈30 ± 2 °C) during 3 months. From the skin penetration data, the microemulsion could enhance the skin penetration of nicotinamide comparing with the solution. Additionally, nicotinamide microemulsion could provide much higher amount of skin retention than that of skin penetration, resulting in suitability for a cosmeceutical product.

  8. [Decellularized fish skin: characteristics that support tissue repair].

    Science.gov (United States)

    Magnússon, Skúli; Baldursson, Baldur Tumi; Kjartansson, Hilmar; Thorlacius, Guðný Ella; Axelsson, Ívar; Rolfsson, Óttar; Petersen, Pétur Henry; Sigurjónsson, Guðmundur Fertram

    2015-12-01

    Acellular fish skin of the Atlantic cod (Gadus morhua) is being used to treat chronic wounds. The prevalence of diabetes and the comorbidity of chronic wounds is increasing globally. The aim of the study was to assess the biocompatibility and biological characteristics of acellular fish skin, important for tissue repair. The structure of the acellular fish skin was examined with microscopy. Biocompatibility of the graft was conducted by a specialized certified laboratory. Protein extracts from the material were analyzed using gel electrophoresis. Cytokine levels were measured with an enzyme linked immunosorbent assay (ELISA). Angiogenic properties were assessed with a chick chorioallantoic membrane (chick CAM) assay. The structure of acellular fish skin is porous and the material is biocompatible. Electrophoresis revealed proteins around the size 115-130 kDa, indicative of collagens. The material did not have significant effect on IL-10, IL-12p40, IL-6 or TNF-α secretion from monocytes or macrophages. Acellular fish skin has significant effect on angiogenesis in the chick CAM assay. The acellular fish skin is not toxic and is not likely to promote inflammatory responses. The graft contains collagen I, promotes angiogenesis and supports cellular ingrowth. Compared to similar products made from mammalian sources, acellular fish skin does not confer a disease risk and contains more bioactive compounds, due to less severe processing.

  9. The relevance of polymeric synthetic membranes in topical formulation assessment and drug diffusion study.

    Science.gov (United States)

    Ng, Shiow-Fern; Rouse, Jennifer J; Sanderson, Francis D; Eccleston, Gillian M

    2012-03-01

    Synthetic membranes are composed of thin sheets of polymeric macromolecules that can control the passage of components through them. Generally, synthetic membranes used in drug diffusion studies have one of two functions: skin simulation or quality control. Synthetic membranes for skin simulation, such as the silicone-based membranes polydimethylsiloxane and Carbosil, are generally hydrophobic and rate limiting, imitating the stratum corneum. In contrast, synthetic membranes for quality control, such as cellulose esters and polysulfone, are required to act as a support rather than a barrier. These synthetic membranes also often contain pores; hence, they are called porous membranes. The significance of Franz diffusion studies and synthetic membranes in quality control studies involves an understanding of the fundamentals of synthetic membranes. This article provides a general overview of synthetic membranes, including a brief background of the history and the common applications of synthetic membranes. This review then explores the types of synthetic membranes, the transport mechanisms across them, and their relevance in choosing a synthetic membrane in Franz diffusion cell studies for formulation assessment purposes.

  10. Screening for skin cancer.

    Science.gov (United States)

    Helfand, M; Mahon, S M; Eden, K B; Frame, P S; Orleans, C T

    2001-04-01

    Malignant melanoma is often lethal, and its incidence in the United States has increased rapidly over the past 2 decades. Nonmelanoma skin cancer is seldom lethal, but, if advanced, can cause severe disfigurement and morbidity. Early detection and treatment of melanoma might reduce mortality, while early detection and treatment of nonmelanoma skin cancer might prevent major disfigurement and to a lesser extent prevent mortality. Current recommendations from professional societies regarding screening for skin cancer vary. To examine published data on the effectiveness of routine screening for skin cancer by a primary care provider, as part of an assessment for the U.S. Preventive Services Task Force. We searched the MEDLINE database for papers published between 1994 and June 1999, using search terms for screening, physical examination, morbidity, and skin neoplasms. For information on accuracy of screening tests, we used the search terms sensitivity and specificity. We identified the most important studies from before 1994 from the Guide to Clinical Preventive Services, second edition, and from high-quality reviews. We used reference lists and expert recommendations to locate additional articles. Two reviewers independently reviewed a subset of 500 abstracts. Once consistency was established, the remainder were reviewed by one reviewer. We included studies if they contained data on yield of screening, screening tests, risk factors, risk assessment, effectiveness of early detection, or cost effectiveness. We abstracted the following descriptive information from full-text published studies of screening and recorded it in an electronic database: type of screening study, study design, setting, population, patient recruitment, screening test description, examiner, advertising targeted at high-risk groups or not targeted, reported risk factors of participants, and procedure for referrals. We also abstracted the yield of screening data including probabilities and numbers

  11. Tissue Banking in Malaysia-amniotic membrane

    International Nuclear Information System (INIS)

    Hashim bin Mohamad; Norimah binti Yusof

    1991-01-01

    Burn treatment using amniotic membranes in some of our patients initiate our own tissue bank starting with a pilot project on procurement, processing and clinical application of irradiated amniotic membrane. The irradiation of amniotic membrane was made possible by the availability of cobalt source at the Nuclear Energy Agency (UTN). With the technical help from the Inter-national Atomic Energy Agency (IAEA) we soon should be able to embark on bone bank to supply local surgeons. Thus the establishment of tissue bank at our institution will further enhance our programme which will include keratinocytes culture for burn, osteocytes culture for bone replacement as well as the use of animal skin for temporary coverage of open wounds

  12. 网上技术市场是双边市场吗?——以浙江网上技术市场为例%Is the Online Technology Market a Two-sided Market?——Taking the Zhejiang Online Technology Market as an Example

    Institute of Scientific and Technical Information of China (English)

    雷梦思; 李华; 王方

    2017-01-01

    This paper tests whether the online technology market is two-sided markets or not based on the judgment benchmark of two-sided markets.Based on the analysis of necessary conditions for the characteristics of two-sided markets in the online technology market,using Zhejiang online technology market as an example,establish the Grainger test model doing empirical test to test that online technology market meets the sufficient conditions for the existence of the two-sided markets (i.e.,cross network externalities) by collecting and collating the quantity of technical problems and technological achievements released from May 2010 to February and conclude that online technology market is a two-sided market.Implement the measurement of the degree of cross network externalities in the online technology market by setting up a hnear regression equation and put forward some problems that can be studied under the framework of the two sided market theory.%从双边市场的判断基准出发,检验网上技术市场是否为双边市场.在对网上技术市场具有双边市场特征的必要条件进行分析的基础上,以中国浙江网上技术市场为例,通过搜集整理其2010年5月至2016年2月发布的技术难题数量和技术成果数量,建立格兰杰检验模型,实证检验网上技术市场满足双边市场存在的充分条件(即具有交叉网络外部性),从而得出网上技术市场是双边市场的结论.并通过建立回归方程,实现网上技术市场交叉网络外部性程度的测度,提出可在双边市场理论框架下进行研究的若干问题.

  13. A wrinkle in flight: the role of elastin fibres in the mechanical behaviour of bat wing membranes.

    Science.gov (United States)

    Cheney, Jorn A; Konow, Nicolai; Bearnot, Andrew; Swartz, Sharon M

    2015-05-06

    Bats fly using a thin wing membrane composed of compliant, anisotropic skin. Wing membrane skin deforms dramatically as bats fly, and its three-dimensional configurations depend, in large part, on the mechanical behaviour of the tissue. Large, macroscopic elastin fibres are an unusual mechanical element found in the skin of bat wings. We characterize the fibre orientation and demonstrate that elastin fibres are responsible for the distinctive wrinkles in the surrounding membrane matrix. Uniaxial mechanical testing of the wing membrane, both parallel and perpendicular to elastin fibres, is used to distinguish the contribution of elastin and the surrounding matrix to the overall membrane mechanical behaviour. We find that the matrix is isotropic within the plane of the membrane and responsible for bearing load at high stress; elastin fibres are responsible for membrane anisotropy and only contribute substantially to load bearing at very low stress. The architecture of elastin fibres provides the extreme extensibility and self-folding/self-packing of the wing membrane skin. We relate these findings to flight with membrane wings and discuss the aeromechanical significance of elastin fibre pre-stress, membrane excess length, and how these parameters may aid bats in resisting gusts and preventing membrane flutter. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  14. Skin manifestations in sulfur mustard exposed victims with ophthalmologic complications: Association between early and late phase

    Directory of Open Access Journals (Sweden)

    Somayeh Hejazi, MD

    Full Text Available Context: Sulfur mustard (SM was used during the Iraq-Iran war (1980–1988. Exposed veterans continue to suffer from its ocular, skin, and respiratory complications. Objective: We aimed to evaluate associations between early (at the time of acute exposure and decades later skin manifestations in individuals with severe ophthalmologic complications secondary to sulfur mustard exposure. Materials and methods: One hundred forty-nine veterans with severe ocular injuries were evaluated for acute and chronic skin complications. Logistic regression models were used to examine the associations between early and late skin manifestations. Results: Late skin complaints were observed in nearly all survivors who had early skin lesions (131 out of 137; 95.62%. Seven out of 12 patients (58.33% who did not have early skin lesions ultimately developed late skin complications. There was a significant relationship between the presence of lesions at the time of exposure and developing late skin complaints (two-sided Fisher's exact test, OR = 15.59, p < 0.001. There was an association between having at least one early skin lesion and occurrence of late skin complications. Survivors with blisters at the time of chemical exposure were more likely to complain of itching (95% CI: 3.63–25.97, p < 0.001, burning (OR = 11.16; 95% CI: 2.97–41.89, p < 0.001, pigmentation changes (OR = 10.17; 95% CI: 2.54–40.75, p = 0.001, dryness (OR = 6.71, 95% CI: 1.22–37.01, p = 0.03 or cherry angioma (OR = 2.59; 95% CI:1.21–5.55, p = 0.01 during the late phase. Using multivariate logistic models, early blisters remained significantly associated with latent skin complaints. Of note, the genitalia and great flexure areas were the most involved anatomical sites for both early and late skin lesions in SM exposed survivors. Conclusion: According to this study, the presence of blisters at the time of exposure to SM is the most important predictor of developing

  15. [A case of skin autograft for skin ulcers in ichthyosis].

    Science.gov (United States)

    Li, Shiwei; Yang, Xiaodong; Liu, Lijun; Tang, Xueyang

    2017-10-28

    Ichthyosis refers to a group of skin diseases characterized by abnormal keratinization of the epidermis, resulting in dryness, roughness and scale of the skin. A girl with ichthyosis, who presented with skin ulcers and infection of the right dorsal foot, was admitted to our department. An autologous razor-thin skin grafting procedure was performed to repair the skin ulcers after debridement and vacuum sealing drain. After 8 months of follow-up, both the donor and recipient site healed well and there were no newly formed ulcers or infections. Although the skin quality of ichthyosis is poor, the lesion area can still be used as donor or recipient cite.

  16. Development of ultra-low pressure reverse osmosis membranes; Choteiatsu gyakushintomaku no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Hirose, M.; Ito, H.; Ohara, T. [Nitto Denko Corp., Osaka (Japan)

    1998-06-05

    Described herein is development of ultra-low pressure reverse osmosis (RO) membranes. The composite RO membrane, which is now widely used, has a cross-sectional structure consisting of an ultrafilter membrane as the support and a very thin skin layer responsible for filtration. It is confirmed that the skin layer is of a pleated structure. Growing this structure can greatly accelerate permeation of water without damaging arresting and durability characteristics of the membrane, and hence is a desired approach. Utilization of molecular structure simulation of the skin layer materials is investigated by the molecular dynamics. The results show that the stable structure of the material for the skin layer in the RO membrane is a network structure with regularly arranged honeycombs, when it should arrest at least 99% of salt. These techniques serve as the bases for development of the ultra-low pressure RO membranes (ES Series), where the skin layer is made of cross-linked, totally aromatic polyamide. The membrane passes twice as large a quantity of water as the conventional one, is highly resistant to chemicals, and arrests 99.7% of salt. 3 refs., 4 figs.

  17. Smoking and skin disease

    DEFF Research Database (Denmark)

    Thomsen, S F; Sørensen, L T

    2010-01-01

    Tobacco smoking is a serious and preventable health hazard that can cause or exacerbate a number of diseases and shorten life expectancy, but the role of smoking as an etiologic factor in the development of skin disease is largely unknown. Although epidemiological evidence is sparse, findings...... suggest that tobacco smoking is a contributing factor in systemic lupus erythematosus, psoriasis, palmoplantar pustulosis, cutaneous squamous cell carcinoma, hidradenitis suppurativa, and genital warts. In contrast, smoking may confer some protective effects and mitigate other skin diseases, notably...... pemphigus vulgaris, pyoderma gangrenosum, aphthous ulcers, and Behçet's disease. Various degenerative dermatologic conditions are also impacted by smoking, such as skin wrinkling and dysregulated wound healing, which can result in post-surgical complications and delayed or even arrested healing of chronic...

  18. Sprayed skin turbine component

    Science.gov (United States)

    Allen, David B

    2013-06-04

    Fabricating a turbine component (50) by casting a core structure (30), forming an array of pits (24) in an outer surface (32) of the core structure, depositing a transient liquid phase (TLP) material (40) on the outer surface of the core structure, the TLP containing a melting-point depressant, depositing a skin (42) on the outer surface of the core structure over the TLP material, and heating the assembly, thus forming both a diffusion bond and a mechanical interlock between the skin and the core structure. The heating diffuses the melting-point depressant away from the interface. Subsurface cooling channels (35) may be formed by forming grooves (34) in the outer surface of the core structure, filling the grooves with a fugitive filler (36), depositing and bonding the skin (42), then removing the fugitive material.

  19. Thyroid and skin

    Directory of Open Access Journals (Sweden)

    Dogra Alka

    2006-01-01

    Full Text Available The association of thyroid disorders with skin manifestations is complex. Both hypothryoidism and hyperthyroidism are known to cause these changes. In order to study this association of skin changes in relation to hypothyroidism, a study was carried out in the outpatients department of Dermatology of Dayanand Medical College and Hospital, Ludhiana, over a period of 3 months from Jan-March 2005. Thirty two patients were enrolled in the study and parameters were noted regarding history, general symptoms, cutaneous signs and associated diseases. We found gain in weight (71.85% and lethargy (65.62% to be the most common complaints. On cutaneous examination, dry, coarse texture of the skin (56%, pigmentary disorders (37.5% and telogen effluvium (40.62% were the most common findings. Other associated disorders were vitiligo, melasma, pemphigus, alopecia areata, xanthelasma palpebrarum, etc.

  20. Environment and the skin

    International Nuclear Information System (INIS)

    Suskind, R.R.

    1990-01-01

    The skin is an important organ of defense adaptation and a portal of entry for xenobiotics. It is vulnerable to physical, chemical, and biologic agents and capable of expressing responses to these agents in a variety of pathologic patterns. These patterns are characterized by morphologic and functional features which are elicited by careful examination and test procedures. Cutaneous cancer may result from exposure to nonionizing as well as ionizing radiation, to specific identifiable chemical hazards, and may be enhanced by trauma. Cutaneous hazards of chemical sources are largely found in the workplace and among consumer products, including drugs and toilet goods. Environmental skin diseases and injuries are preventable. Prior to use assessment for safety and for possible risks from exposure to an agent, product, or process is of primary importance in the prevention and control of environmental skin disease and injury

  1. Precancerous Skin Lesions.

    Science.gov (United States)

    Ferrándiz, C; Malvehy, J; Guillén, C; Ferrándiz-Pulido, C; Fernández-Figueras, M

    Certain clinically and histologically recognizable skin lesions with a degree of risk of progression to squamous cell carcinoma have been traditionally grouped as precancerous skin conditions but now tend to be classified as in situ carcinomas. This consensus statement discusses various aspects of these lesions: their evaluation by means of clinical and histopathologic features, the initial evaluation of the patient, the identification of risk factors for progression, and the diagnostic and treatment strategies available today. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. Skin graft viability test

    International Nuclear Information System (INIS)

    Wahner, H.W.; Robertson, J.S.

    1983-01-01

    With respect to skin pedicles (tubular pedicle or direct flap), an estimation of the blood supply is of great importance in making a decision as to when to perform the separation from the original blood supply. This decision is based on empiric observation of the normal time of healing and varies greatly with the site and the concepts of the individual surgery. A number of methods have been proposed for testing the circulation of pedicle skin flaps or tubes, and these methods all seem more complicated and less accurate than the isotope method that is described in this chapter

  3. Skin innate immune system

    Directory of Open Access Journals (Sweden)

    Berna Aksoy

    2013-06-01

    Full Text Available All multicellular organisms protect themselves from external universe and microorganisms by innate immune sytem that is constitutively present. Skin innate immune system has several different components composed of epithelial barriers, humoral factors and cellular part. In this review information about skin innate immune system and its components are presented to the reader. Innate immunity, which wasn’t adequately interested in previously, is proven to provide a powerfull early protection system, control many infections before the acquired immunity starts and directs acquired immunity to develop optimally

  4. Going skin deep: A direct comparison of penetration potential of lipid-based nanovesicles on the isolated perfused human skin flap model.

    Science.gov (United States)

    Ternullo, Selenia; de Weerd, Louis; Holsæter, Ann Mari; Flaten, Gøril Eide; Škalko-Basnet, Nataša

    2017-12-01

    Phospholipid-based nanocarriers are attractive drug carriers for improved local skin therapy. In the present study, the recently developed isolated perfused human skin flap (IPHSF) model was used to directly compare the skin penetration enhancing potential of the three commonly used nanocarriers, namely conventional liposomes (CLs), deformable liposomes (DLs) and solid lipid nanoparticles (SLNs). Two fluorescent markers, calcein (hydrophilic) or rhodamine (lipophilic), were incorporated individually in the three nanosystems. The nanocarrier size ranged between 200 and 300nm; the surface charge and entrapment efficiency for both markers were dependent on the lipid composition and the employed surfactant. Both carrier-associated markers could not penetrate the full thickness human skin, confirming their suitability for dermal drug delivery. CLs exhibited higher retention of both markers on the skin surface compared to DLs and SLNs, indicating a depo formation. DLs and SLNs enabled the deeper penetration of the two markers into the skin layers. In vitro and ex vivo skin penetration studies performed on the cellophane membrane and full thickness pig/human skin, respectively, confirmed the findings. In conclusion, efficient dermal drug delivery can be achieved by optimization of a lipid nanocarrier on the suitable skin-mimicking model to assure system's accumulation in the targeted skin layer. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Therapeutic potential of the anti-diabetic agent metformin in targeting the skin cancer stem cell diaspora.

    Science.gov (United States)

    Reddi, Anand; Powers, Matthew A; Dellavalle, Robert P

    2014-05-01

    Type II diabetes is associated with increased prevalence of cancer including both melanoma and squamous cell carcinoma (SCC) of the skin. Emerging evidence from epidemiological studies suggest that diabetic patients on metformin have a lower risk of cancer incidence and mortality in a broad range of neoplasms. In both melanoma and SCC, populations of cancer stem cells (CSC) contribute to tumor initiation and metastasis. We propose that metformin constitutes a new class of targeted therapy that acts on the skin CSC diaspora. We posit that metformin selectively and simultaneously targets CSCs of the primary tumor as well as in metastatic niches thereby disrupting the dynamic dispersal of circulating CSCs between the primary tumor and metastatic site. This hypothesis suggests a new concept in dermato-oncology that treatment of type II diabetes and prevention of skin cancer are two sides of the same coin. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. 交叉网络外部性还是单向网络外部性?——传媒业内的双边市场辨析%Cross-Product Network Externalities or Unilateral Network Externalities: Analysis of Two-Sided-Market in Media Industry

    Institute of Scientific and Technical Information of China (English)

    张辉锋

    2012-01-01

    This paper mainly discusses whether media industry has two-sided-market or not. It focuses on two categories which are mostly similar to two-sided-market: one is Internet advertising alliance, copyright exchange base, content products trade fair, etc., the other is the press and broadcasting markets. It finds that the former belongs to two-sided-market while the latter does not since there is no cross-product network externalities between advertiser and audience. It also argues that the former should refer to the pricing strategy of two-sided-market and there is no need for the latter to take care of the influence of the pricing strategy on audiences.%本论文利用双边市场理论对传媒业进行辨析,以厘清传媒业中是否存在双边市场。辨析主要集中在与双边市场最贴近的两类,一是互联网广告联盟、版权交易基地、内容产品展销会等,一是报刊广电等传媒。结论是前者属于双边市场,后者由于广告主与受众两边市场不存在交叉网络外部性而不是。论文还指出,前者的定价应多借鉴双边市场定价策略的相关内容,而后者对广告主的定价可不考虑对受众的影响。

  7. Asymmetric block copolymer membranes with ultrahigh porosity and hierarchical pore structure by plain solvent evaporation

    KAUST Repository

    Yu, H.

    2016-09-14

    Membranes with a hierarchical porous structure could be manufactured from a block copolymer blend by pure solvent evaporation. Uniform pores in a 30 nm thin skin layer supported by a macroporous structure were formed. This new process is attractive for membrane production because of its simplicity and the lack of liquid waste.

  8. Asymmetric block copolymer membranes with ultrahigh porosity and hierarchical pore structure by plain solvent evaporation

    KAUST Repository

    Yu, H.; Qiu, Xiaoyan; Behzad, Ali Reza; Musteata, Valentina-Elena; Smilgies, D.-M.; Nunes, Suzana Pereira; Peinemann, Klaus-Viktor

    2016-01-01

    Membranes with a hierarchical porous structure could be manufactured from a block copolymer blend by pure solvent evaporation. Uniform pores in a 30 nm thin skin layer supported by a macroporous structure were formed. This new process is attractive for membrane production because of its simplicity and the lack of liquid waste.

  9. A survey of structure characterization methods for ultrafiltration and reverse osmosis membranes

    NARCIS (Netherlands)

    Smolders, C.A.; Mulder, M.H.V.; van der Velden, P.M.

    1976-01-01

    Asymmetric membranes consist of a thin skin, which is permselective to certain molecules in solution, and a porous support, serving as a mechanical support layer and also as a transport layer for the permeate. Both in ultrafiltration and in hyperfiltration (reverse osmosis) asymmetric membranes are

  10. Skin dosimetry - radiological protection aspects of skin dosimetry

    International Nuclear Information System (INIS)

    Dennis, J.A.

    1991-01-01

    Following a Workshop in Skin Dosimetry, a summary of the radiological protection aspects is given. Aspects discussed include routine skin monitoring and dose limits, the need for careful skin dosimetry in high accidental exposures, techniques for assessing skin dose at all relevant depths and the specification of dose quantities to be measured by personal dosemeters and the appropriate methods to be used in their calibration. (UK)

  11. Frog skin function revisited

    DEFF Research Database (Denmark)

    Hviid Larsen, Erik; Ramløv, Hans

    2013-01-01

    of the epidermis. These mechanisms have evolved pari passu with life alternating between aquatic and terrestrial habitats associated with permeabilities of the skin controlled by external ion- and osmotic concentrations (loc. cit.). This allows for fast switching of the cutaneous uptake of chloride between active...

  12. Skin Cut Construction

    DEFF Research Database (Denmark)

    2017-01-01

    of the exhibition is to create a connection between the artistic and technological development through Danish rms and researchers who represent the newest technology in concrete treatment. The rst part exhibition (skin) will focus on the surface treatment of concrete (’graphical concrete’), the second (cut...

  13. Mechanical modeling of skin

    NARCIS (Netherlands)

    Oomens, C.W.J.; Peters, G.W.M.; Kassab, G.S.; Sacks, M.S.

    2016-01-01

    The chapter describes the work that was performed in the soft tissue biomechanics laboratory at Eindhoven University of Technology on the biomechanics of skin. A rationale is given for the changes from standard testing methods to inverse methods, from in vitro to in vivo and back to in vitro testing

  14. Preventing Skin Cancer

    Centers for Disease Control (CDC) Podcasts

    2016-05-18

    A man and a woman talk about how they’ve learned to protect their skin from the sun over the years. .  Created: 5/18/2016 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 5/18/2016.

  15. Skin Cancer Trends

    Science.gov (United States)

    ... Children from the Sun? Are There Benefits to Spending Time Outdoors? The Surgeon General’s Call to Action to Prevent Skin Cancer Related Resources Sun Safety Tips for Men Tips for Families Tips for Schools Tips for Employers Tips for ...

  16. Immunity and skin cancer

    International Nuclear Information System (INIS)

    Smith, E.B.; Brysk, M.M.

    1981-01-01

    Observations in humans and animal studies support the theory that immunologic surveillance plays an important role in limiting the development of skin malignancies. These immune responses undergo progressive diminution with age. In addition, other factors, such as bereavement, poor nutrition, and acute and chronic exposure to ultraviolet light, can further diminish immune mechanisms

  17. Examine Your Skin

    Medline Plus

    Full Text Available ... us for One-on-One Support Donate Share Facebook Twitter Newsletter Examine Your Skin Watch the video ... 29498 © 2013 Melanoma International Foundation. All Rights Reserved. Privacy Policy | Terms of Use Toll-free: 866-463- ...

  18. Skin lesion removal

    Science.gov (United States)

    ... likely to be done when there is a concern about a skin cancer. Most often, an area the shape of an ellipse is removed, as this makes it easier to close with stitches. The entire lesion is removed, going as deep as the fat, if needed, to ...

  19. Skin painting studies

    International Nuclear Information System (INIS)

    Witschi, H.P.; Smith, L.H.; Goad, M.E.; Anthony, W.B.; Gipson, L.C.; Stephens, T.J.; Whitaker, M.S.

    1987-01-01

    In order to estimate eventual risks to human health as a consequence of incidental and prolonged skin contact, it is necessary to obtain some information on the potential of coal-derived liquids to elicit skin cancer. In addition, it also must be established whether prolonged dermal exposure will produce signs of toxicity not only on the skin but to internal organs. During the past 2 years, they completed a life-long skin painting study with mice designed to answer some of these questions. The following materials were tested: Raw H-coal blend, containing 5700 ppm N; H-coal blend after low hydrotreatment (2650 ppm N); H-coal blend after high hydrotreatment (0.2 ppm N); H-coal home heating oil, a devolatilized version of the high-hydrotreatment H-coal blend; and an H-coal reformed naphtha. Two petroleum-derived references samples were used: Petroleum No. 2 fuel oil and high catalytically cracked naphtha. Benzo(a)pyrene was used as reference substance. Experimental animals were male and female C3H mice

  20. Light and skin disease

    International Nuclear Information System (INIS)

    Bauer, R.

    1991-01-01

    Because of the depletion of ozone in the stratosphere due to chlorofluorocarbons, the screening effect of this ozone layer on ultraviolet radiation (especially the so-called UV-B component) is reduced. This paper describes the impact of increased UV radiation on the human skin. Because of the 'ozone-hole', a distinct increase in the rate of skin cancer is to be expected which will affect all living beings but most of all man - an indirect consequence of the climate development. What makes the increased intensity of UV-B radiation so harmful is the fact that light-induced skin damage accumulates for the period of the life-time of the individual and cannot be reversed. A further thinning of stratospheric ozone would let through, in addition, the more short-waved ('harder') UV-C radiation. The latter, though clinically not significant currently, would then account for a further increase in the rate of malignant skin disease world-wide. (orig.) [de

  1. Skin peeling syndrome

    Directory of Open Access Journals (Sweden)

    Gharpuray Mohan

    1994-01-01

    Full Text Available We are reporting a case of skin peeling syndrome, a rare disorder in which sudden generalized exfoliation of the stratum corneum occurs. Histopathologically, there was well formed subcorneal pustule filled with polymorphs and nuclear dust, considering this to be a varient of subcorneal pustular dermatosis, we have put the patient on Dapsone.

  2. Fabrication of Polybenzimidazole/Palladium Nanoparticles Hollow Fiber Membranes for Hydrogen Purification

    KAUST Repository

    Villalobos, Luis Francisco

    2017-09-13

    A novel scheme to fabricate polybenzimidazole (PBI) hollow fiber membranes with a thin skin loaded with fully dispersed palladium nanoparticles is proposed for the first time. Palladium is added to the membrane during the spinning process in the form of ions that coordinate to the imidazole groups of the polymer. This is attractive for membrane production because agglomeration of nanoparticles is minimized and the high-cost metal is incorporated in only the selective layer—where it is required. Pd-containing membranes achieve three orders of magnitude higher H2 permeances and a twofold improvement in H2/CO2 selectivity compared to pure PBI hollow fiber membranes.

  3. Skin color independent assessment of aging using skin autofluorescence

    NARCIS (Netherlands)

    Koetsier, M.; Nur, Erfan; Chunmao, Han; Lutgers, Helen L.; Links, Thera P.; Smit, Andries J.; Rakhorst, Gerhard; Graaff, Reindert

    2010-01-01

    Skin autofluorescence (AF) for the non-invasive assessment of the amount of accumulated tissue Advanced Glycation Endproducts (AGEs) increases with aging. In subjects with darker skin colors, measurements typically result in lower AF values than in subjects with fair skin colors, e.g. due to

  4. Skin color independent assessment of aging using skin autofluorescence

    NARCIS (Netherlands)

    Koetsier, M.; Nur, E.; Chunmao, H.; Lutgers, H.L.; Links, T.P.; Smit, A.J.; Rakhorst, G.; de Graaff, R.

    2010-01-01

    Skin autofluorescence (AF) for the non-invasive assessment of the amount of accumulated tissue Advanced Glycation Endproducts (AGEs) increases with aging. In subjects with darker skin colors, measurements typically result in lower AF values than in subjects with fair skin colors, e. g. due to

  5. A new method for skin color enhancement

    Science.gov (United States)

    Zeng, Huanzhao; Luo, Ronnier

    2012-01-01

    Skin tone is the most important color category in memory colors. Reproducing it pleasingly is an important factor in photographic color reproduction. Moving skin colors toward their preferred skin color center improves the skin color preference on photographic color reproduction. Two key factors to successfully enhance skin colors are: a method to detect original skin colors effectively even if they are shifted far away from the regular skin color region, and a method to morph skin colors toward a preferred skin color region properly without introducing artifacts. A method for skin color enhancement presented by the authors in the same conference last year applies a static skin color model for skin color detection, which may miss to detect skin colors that are far away from regular skin tones. In this paper, a new method using the combination of face detection and statistical skin color modeling is proposed to effectively detect skin pixels and to enhance skin colors more effectively.

  6. Candida infection of the skin

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000880.htm Candida infection of the skin To use the sharing features on this page, please enable JavaScript. Candida infection of the skin is a yeast infection ...

  7. Nanoclay embedded mixed matrix PVDF nanocomposite membrane: Preparation, characterization and biofouling resistance

    Energy Technology Data Exchange (ETDEWEB)

    Rajabi, Hamid [Membrane Research Centre, Department of Chemical Engineering, Razi University, Tagh Bostan, 67149 Kermanshah (Iran, Islamic Republic of); Department of Civil Engineering, Razi University, 67149 Kermanshah (Iran, Islamic Republic of); Ghaemi, Negin, E-mail: negin_ghaemi@kut.ac.ir [Department of Chemical Engineering, Kermanshah University of Technology, 67178 Kermanshah (Iran, Islamic Republic of); Madaeni, Sayed S. [Membrane Research Centre, Department of Chemical Engineering, Razi University, Tagh Bostan, 67149 Kermanshah (Iran, Islamic Republic of); Daraei, Parisa [Department of Chemical Engineering, Kermanshah University of Technology, 67178 Kermanshah (Iran, Islamic Republic of); Khadivi, Mohammad Ali [Friedrich-Alexander University, Erlangen-Nuremberg, Egerland Strasse 3, D-91058 Erlangen (Germany); Falsafi, Monir [Department of Chemistry, Faculty of Science, Razi University, 67149 Kermanshah (Iran, Islamic Republic of)

    2014-09-15

    Highlights: • Nanocomposite membranes were prepared by addition of OMMT to PVDF membrane. • Addition of nanoclay considerably increased the hydrophilicity of PVDF membrane. • Nanocomposite membranes had higher water flux and antifouling properties. • Fouling of membranes blended with nanoclay (<4 wt.%) reduced. - Abstract: In this paper, nanocomposite PVDF/nanoclay membranes were prepared with addition of different concentrations of organically modified montmorillonite (OMMT) into the polymeric casting solution using combination of solution dispersion and phase inversion methods. Membranes were characterized by use of X-ray diffraction (XRD), water contact angle, scanning electron microscopy (SEM) and atomic force microscopy (AFM), and their performances were evaluated in terms of pure water flux and fouling parameters. The surface hydrophilicity of all nanocomposites markedly improved compared to nascent PVDF. In addition, XRD patterns revealed the formation of intercalated layers of mineral clays in PVDF matrix. SEM and AFM images showed that addition of OMMT resulted in nanocomposite membranes with thinner skin layer and higher porosity rather than PVDF membranes. Pure water flux of PVDF/OMMT membranes increased significantly (particularly for fabricated membranes by 4 and 6 wt.% OMMT) compared to that of PVDF membrane. Moreover, nanocomposite membranes showed the elevated antifouling properties, and flux recovery of nascent PVDF membranes increased from 51 to 72% with addition of 2 wt.% OMMT nanoparticles. These nanocomposite membranes also offered a remarkable reusability and durability against biofouling.

  8. Nanoclay embedded mixed matrix PVDF nanocomposite membrane: Preparation, characterization and biofouling resistance

    International Nuclear Information System (INIS)

    Rajabi, Hamid; Ghaemi, Negin; Madaeni, Sayed S.; Daraei, Parisa; Khadivi, Mohammad Ali; Falsafi, Monir

    2014-01-01

    Highlights: • Nanocomposite membranes were prepared by addition of OMMT to PVDF membrane. • Addition of nanoclay considerably increased the hydrophilicity of PVDF membrane. • Nanocomposite membranes had higher water flux and antifouling properties. • Fouling of membranes blended with nanoclay (<4 wt.%) reduced. - Abstract: In this paper, nanocomposite PVDF/nanoclay membranes were prepared with addition of different concentrations of organically modified montmorillonite (OMMT) into the polymeric casting solution using combination of solution dispersion and phase inversion methods. Membranes were characterized by use of X-ray diffraction (XRD), water contact angle, scanning electron microscopy (SEM) and atomic force microscopy (AFM), and their performances were evaluated in terms of pure water flux and fouling parameters. The surface hydrophilicity of all nanocomposites markedly improved compared to nascent PVDF. In addition, XRD patterns revealed the formation of intercalated layers of mineral clays in PVDF matrix. SEM and AFM images showed that addition of OMMT resulted in nanocomposite membranes with thinner skin layer and higher porosity rather than PVDF membranes. Pure water flux of PVDF/OMMT membranes increased significantly (particularly for fabricated membranes by 4 and 6 wt.% OMMT) compared to that of PVDF membrane. Moreover, nanocomposite membranes showed the elevated antifouling properties, and flux recovery of nascent PVDF membranes increased from 51 to 72% with addition of 2 wt.% OMMT nanoparticles. These nanocomposite membranes also offered a remarkable reusability and durability against biofouling

  9. Folate in Skin Cancer Prevention

    OpenAIRE

    Williams, J.D.; Jacobson, Elaine L.; Kim, H.; Kim, M.; Jacobson, M.K.

    2012-01-01

    Skin, the largest, most exposed organ of the body, provides a protective interface between humans and the environment. One of its primary roles is protection against exposure to sunlight, a major source of skin damage where the UV radiation (UVR) component functions as a complete carcinogen. Melanin pigmentation and the evolution of dark skin is an adaptive protective mechanism against high levels of UVR exposure. Recently, the hypothesis that skin pigmentation balances folate preservation an...

  10. LOCALIZATION OF PERMEABILITY BARRIERS IN THE FROG SKIN EPITHELIUM

    Science.gov (United States)

    Martinez-Palomo, A.; Erlij, D.; Bracho, H.

    1971-01-01

    Ruthenium red and colloidal lanthanum were used to determine the site of the structural barriers to diffusion within the intercellular spaces of frog skin epithelium. Electron micrographs show that occluding zonules located at the outer border of the stratum corneum and at the outer layer of the stratum granulosum are true tight junctions since they are impermeable to these tracers. Measurement of 140La uptake by the living skin shows that lanthanum moves across the external surface of the skin readily, into and out of a compartment that has a limited capacity and is bounded on its internal side by a barrier impermeable to lanthanum. Examination of these skins with the electron microscope suggests that the compartment is localized between the external membrane of the cells at the outer layer of the s. granulosum and at the outermost surface of the skin. These observations and other findings described in the literature indicate that the site of the external high resistance barrier of the frog skin is localized at the outer border of the s. granulosum. PMID:4329611

  11. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T [Huntington Beach, CA; Sahimi, Muhammad [Altadena, CA; Fayyaz-Najafi, Babak [Richmond, CA; Harale, Aadesh [Los Angeles, CA; Park, Byoung-Gi [Yeosu, KR; Liu, Paul K. T. [Lafayette Hill, PA

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  12. Premature rupture of membranes

    Science.gov (United States)

    ... gov/ency/patientinstructions/000512.htm Premature rupture of membranes To use the sharing features on this page, ... water that surrounds your baby in the womb. Membranes or layers of tissue hold in this fluid. ...

  13. Oxygen transport membrane

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a novel composite oxygen transport membrane as well as its preparation and uses thereof.......The present invention relates to a novel composite oxygen transport membrane as well as its preparation and uses thereof....

  14. Membrane with integrated spacer

    NARCIS (Netherlands)

    Balster, J.H.; Stamatialis, Dimitrios; Wessling, Matthias

    2010-01-01

    Many membrane processes are severely influenced by concentration polarisation. Turbulence promoting spacers placed in between the membranes can reduce the diffusional resistance of concentration polarisation by inducing additional mixing. Electrodialysis (ED) used for desalination suffers from

  15. Gel layer formation on membranes in Membrane Bioreactors

    NARCIS (Netherlands)

    Van den Brink, P.F.H.

    2014-01-01

    The widespread application of membrane bioreactors (MBRs) for municipal wastewater treatment is hampered by membrane fouling. Fouling increases energy demand, reduces process performance and creates the need for more frequent (chemical) membrane cleaning or replacement. Membrane fouling in MBRs is

  16. Smart membranes for monitoring membrane based desalination processes

    KAUST Repository

    Laleg-Kirati, Taous-Meriem; Karam, Ayman M.

    2017-01-01

    Various examples are related to smart membranes for monitoring membrane based process such as, e.g., membrane distillation processes. In one example, a membrane, includes a porous surface and a plurality of sensors (e.g., temperature, flow and

  17. Skin Pedagogies and Abject Bodies

    Science.gov (United States)

    Kenway, Jane; Bullen, Elizabeth

    2011-01-01

    How does the beauty industry "narrate the skin"? What does it teach women from different cultural groups about the female body? How does skin function as a site where female subjection and abjection are produced and reproduced? In this paper we examine the skin industry pointing to its extreme commodification of the female body and to the…

  18. Maintaining Healthy Skin -- Part 2

    Science.gov (United States)

    ... and SCI • Depression and SCI • Taking Care of Pressure Sores • Maintaining Healthy Skin (Part I) • Maintaining Healthy Skin ( ... For information on establishing skin tolerance, see our “Pressure Sores” pamphlet.) Pressure releases in a wheelchair can be ...

  19. Maintaining Healthy Skin -- Part 1

    Science.gov (United States)

    ... with no breaks in the surface. It is warm (not hot or red) and neither dry and flaky nor moist and wrinkled. Healthy skin is a mirror of a healthy body. How to take care of your skin NUTRITION: To keep your skin healthy, eat a well- ...

  20. Skin Cancers of the Feet

    Science.gov (United States)

    ... Foot Health Awareness Month Diabetes Awareness What Are Skin Cancers of the Feet? Skin cancer can develop anywhere on the body, including ... cell carcinoma is the most common form of cancer on the skin of the feet. Most types of early squamous ...

  1. ICRP-26 and skin contamination

    International Nuclear Information System (INIS)

    Finnigan, T.; Huda, W.; Newbery, G.R.

    1979-01-01

    The experience of dealing with skin contamination incidents at The Radiochemical Centre over a 3-year period is presented. Data are given for the primary isotopes involved, the duration of skin contamination, and the skin doses that arise from these incidents. The methods employed in performing dosimetry for skin contamination are discussed and examples involving the isotopes carbon-14 and indium-111 are described. For skin contamination incidents, the mode of penetration of the activity into skin is normally not known and this can be of major significance for the final skin dose estimate. The operational health physics difficulties encountered in complying with both ICRP-26 and UK legislation for skin contamination are considered. In the event of multiple exposure (i.e. skin doses calculated from whole body film badges, extremity TLD dose meters and skin contamination) there is ambiguity in the precise meaning of the skin dose. The usefulness of Derived Working Levels is also discussed. Experience at The Radiochemical Centre has shown that good plant design, proper training and prompt action in dealing with contamination incidents ensures that overexposures to skin from accidental contamination are rare occurrences. (author)

  2. Evaluation of dermal-epidermal skin equivalents ('composite-skin') of human keratinocytes in a collagen-glycosaminoglycan matrix(Integra artificial skin).

    Science.gov (United States)

    Kremer, M; Lang, E; Berger, A C

    2000-09-01

    Integra artificial skin (Integra LifeSciences Corp., Plainsboro, NJ, USA) is a dermal template consisting of bovine collagen, chondroitin-6-sulphate and a silastic membrane manufactured as Integra. This product has gained widespread use in the clinical treatment of third degree burn wounds and full thickness skin defects of different aetiologies. The product was designed to significantly reduce the time needed to achieve final wound closure in the treatment of major burn wounds, to optimise the sparse autologous donor skin resources and to improve the durable mechanical quality of the skin substitute. The clinical procedure requires two stages. The first step creates a self neodermis, the second creates a self epidermis on the neodermis. However, it is desirable to cover major burn wounds early in a single step by a skin substitute consisting of a dermal equivalent seeded in vitro with autologous keratinocytes ('composite-skin') out of which a full thickness skin develops in vivo.The goal of this experimental study was to develop a method to integrate human keratinocytes in homogeneous distribution and depth into Integra Artificial Skin. The seeded cell-matrix composites were grafted onto athymic mice in order to evaluate their potential to reconstitute a human epidermis in vivo. We were able to demonstrate that the inoculated human keratinocytes reproducibly displayed a homogeneous pattern of distribution, adherence, proliferation and confluence. The cell-matrix composites grafted in this model exhibited good wound adherence, complete healing, minor wound contraction and had the potential to reconstitute an elastic, functional and durable human skin. Histologically we were able to show that the inoculated human keratinocytes in vivo colonised the matrix in a histomorphologically characteristic epidermal pattern (keratomorula, keratinocyte bubbling) and developed a persisting, stratified, keratinising epidermis which immunohistologically proved to be of human

  3. Model cell membranes

    DEFF Research Database (Denmark)

    Günther-Pomorski, Thomas; Nylander, Tommy; Cardenas Gomez, Marite

    2014-01-01

    The high complexity of biological membranes has motivated the development and application of a wide range of model membrane systems to study biochemical and biophysical aspects of membranes in situ under well defined conditions. The aim is to provide fundamental understanding of processes control...

  4. Idiopathic epiretinal membrane

    NARCIS (Netherlands)

    Bu, Shao-Chong; Kuijer, Roelof; Li, Xiao-Rong; Hooymans, Johanna M M; Los, Leonoor I

    2014-01-01

    Background: Idiopathic epiretinal membrane (iERM) is a fibrocellular membrane that proliferates on the inner surface of the retina at the macular area. Membrane contraction is an important sight-threatening event and is due to fibrotic remodeling. Methods: Analysis of the current literature

  5. Meniscus Membranes For Separation

    Science.gov (United States)

    Dye, Robert C.; Jorgensen, Betty; Pesiri, David R.

    2005-09-20

    Gas separation membranes, especially meniscus-shaped membranes for gas separations are disclosed together with the use of such meniscus-shaped membranes for applications such as thermal gas valves, pre-concentration of a gas stream, and selective pre-screening of a gas stream. In addition, a rapid screening system for simultaneously screening polymer materials for effectiveness in gas separation is provided.

  6. Meniscus membranes for separations

    Science.gov (United States)

    Dye, Robert C [Irvine, CA; Jorgensen, Betty [Jemez Springs, NM; Pesiri, David R [Aliso Viejo, CA

    2004-01-27

    Gas separation membranes, especially meniscus-shaped membranes for gas separations are disclosed together with the use of such meniscus-shaped membranes for applications such as thermal gas valves, pre-concentration of a gas stream, and selective pre-screening of a gas stream. In addition, a rapid screening system for simultaneously screening polymer materials for effectiveness in gas separation is provided.

  7. Skin Cancer: Biology, Risk Factors & Treatment

    Science.gov (United States)

    ... turn Javascript on. Feature: Skin Cancer Skin Cancer: Biology, Risk Factors & Treatment Past Issues / Summer 2013 Table ... Articles Skin Cancer Can Strike Anyone / Skin Cancer: Biology, Risk Factors & Treatment / Timely Healthcare Checkup Catches Melanoma ...

  8. Behavioral Counseling to Prevent Skin Cancer

    Science.gov (United States)

    ... it might mean for you. What is skin cancer? Skin cancer is cancer that occurs in different kinds ... squamous cell carcinoma, and melanoma. Facts About Skin Cancer Skin cancer is the most common type of cancer ...

  9. Genetics Home Reference: acral peeling skin syndrome

    Science.gov (United States)

    ... Home Health Conditions Acral peeling skin syndrome Acral peeling skin syndrome Printable PDF Open All Close All ... to view the expand/collapse boxes. Description Acral peeling skin syndrome is a skin disorder characterized by ...

  10. Electrically Driven Ion Separations in Permeable Membranes

    Energy Technology Data Exchange (ETDEWEB)

    Bruening, Merlin [Michigan State Univ., East Lansing, MI (United States)

    2017-04-21

    Membranes are attractive for a wide range of separations due to their low energy costs and continuous operation. To achieve practical fluxes, most membranes consist of a thin, selective skin on a highly permeable substrate that provides mechanical strength. Thus, this project focused on creating new methods for forming highly selective ultrathin skins as well as modeling transport through these coatings to better understand their unprecedented selectivities. The research explored both gas and ion separations, and the latter included transport due to concentration, pressure and electrical potential gradients. This report describes a series of highlights of the research and then provides a complete list of publications supported by the grant. These publications have been cited more than 4000 times. Perhaps the most stunning finding is the recent discovery of monovalent/divalent cation and anion selectivities around 1000 when modifying cation- and anion-exchange membranes with polyelectrolyte multilayers (PEMs). This discovery builds on many years of exciting research. (Citation numbers refer to the journal articles in the bibliography.)

  11. Skin contamination dosimeter

    Science.gov (United States)

    Hamby, David M [Corvallis, OR; Farsoni, Abdollah T [Corvallis, OR; Cazalas, Edward [Corvallis, OR

    2011-06-21

    A technique and device provides absolute skin dosimetry in real time at multiple tissue depths simultaneously. The device uses a phoswich detector which has multiple scintillators embedded at different depths within a non-scintillating material. A digital pulse processor connected to the phoswich detector measures a differential distribution (dN/dH) of count rate N as function of pulse height H for signals from each of the multiple scintillators. A digital processor computes in real time from the differential count-rate distribution for each of multiple scintillators an estimate of an ionizing radiation dose delivered to each of multiple depths of skin tissue corresponding to the multiple scintillators embedded at multiple corresponding depths within the non-scintillating material.

  12. Ablative skin resurfacing.

    Science.gov (United States)

    Agrawal, Nidhi; Smith, Greg; Heffelfinger, Ryan

    2014-02-01

    Ablative laser resurfacing has evolved as a safe and effective treatment for skin rejuvenation. Although traditional lasers were associated with significant thermal damage and lengthy recovery, advances in laser technology have improved safety profiles and reduced social downtime. CO2 lasers remain the gold standard of treatment, and fractional ablative devices capable of achieving remarkable clinical improvement with fewer side effects and shorter recovery times have made it a more practical option for patients. Although ablative resurfacing has become safer, careful patient selection and choice of suitable laser parameters are essential to minimize complications and optimize outcomes. This article describes the current modalities used in ablative laser skin resurfacing and examines their efficacy, indications, and possible side effects. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  13. Development of human skin equivalents to unravel the impaired skin barrier in atopic dermatitis skin

    NARCIS (Netherlands)

    Eweje, M.O.

    2016-01-01

    The studies in this thesis describes the barrier defects in Atopic Dermatitis (AD) skin and various techniques to develop AD Human Skin Equivalents (HSEs) which can be used to better understand the role of several factors in the pathogenesis of AD skin. The results described show that Inflammation

  14. Vibroacoustic Skin Diagnostics Modeling

    Directory of Open Access Journals (Sweden)

    Svetlana М. Yatsun

    2013-01-01

    Full Text Available The article deals with the mathematical modeling of biological diagnosis of complex heterogeneous structure (skin, using non-destructive control method. The mathematical model, describing interaction of the material with electrodynamic vibration generator and sensor system, controlling the propagation of small disturbances was developed. The influence of material model parameters on the spectrum in the course of the propagation of the surface disturbance

  15. Skin barrier composition

    International Nuclear Information System (INIS)

    Osburn, F.G.

    1985-01-01

    A skin barrier composition comprises a mixture of a copolymer resin of ethylene and vinyl acetate (EVA), and a water-insoluble dry tack-providing elastomer such as polyisobutylene. The composition after mixing and molding, is subjected to ionizing irradiation to form cross-linked polymer networks of the EVA. The compositions have exceptional properties for use as barrier sheets, rings, or strips in ostomy, wound drainage, and incontinence devices. (author)

  16. Skin barrier composition

    Energy Technology Data Exchange (ETDEWEB)

    Osburn, F G

    1985-06-12

    A skin barrier composition comprises a mixture of a copolymer resin of ethylene and vinyl acetate (EVA), and a water-insoluble dry tack-providing elastomer such as polyisobutylene. The composition after mixing and molding, is subjected to ionizing irradiation to form cross-linked polymer networks of the EVA. The compositions have exceptional properties for use as barrier sheets, rings, or strips in ostomy, wound drainage, and incontinence devices.

  17. Defective channels lead to an impaired skin barrier.

    Science.gov (United States)

    Blaydon, Diana C; Kelsell, David P

    2014-10-15

    Channels are integral membrane proteins that form a pore, allowing the passive movement of ions or molecules across a membrane (along a gradient), either between compartments within a cell, between intracellular and extracellular environments or between adjacent cells. The ability of cells to communicate with one another and with their environment is a crucial part of the normal physiology of a tissue that allows it to carry out its function. Cell communication is particularly important during keratinocyte differentiation and formation of the skin barrier. Keratinocytes in the skin epidermis undergo a programme of apoptosis-driven terminal differentiation, whereby proliferating keratinocytes in the basal (deepest) layer of the epidermis stop proliferating, exit the basal layer and move up through the spinous and granular layers of the epidermis to form the stratum corneum, the external barrier. Genes encoding different families of channel proteins have been found to harbour mutations linked to a variety of rare inherited monogenic skin diseases. In this Commentary, we discuss how human genetic findings in aquaporin (AQP) and transient receptor potential (TRP) channels reveal different mechanisms by which these channel proteins function to ensure the proper formation and maintenance of the skin barrier. © 2014. Published by The Company of Biologists Ltd.

  18. SKIN RADIATION IN PANORAMIC

    Directory of Open Access Journals (Sweden)

    Herry Irawan

    2015-06-01

    Full Text Available Dental panoramic radiograph in Indonesia has been widely used. Modern diagnostic imaging equipment with minimum radiation is still very limited. One of the conditions in nuclear safety law, UU 10/1997, is an optimization of all radiation sources with DRL through skin dose measurements. In Indonesia, the national DRL has not been established yet, and there were no reports on the study of panoramic skin dose in Indonesia. The aim of this preliminary study was to obtain a panoramic skin dose radiation as reference to establish DRL in Indonesia. Panoramic radiographs of sixteen female and fifteen male patients, aged 4 – 48 years, were taken using the standard conventional method, with TLD chips attached in location groups. The chips were then read with the detector and integrator of BATAN, in high and low temperature condition at the same time. It was revealed that behind the right and left ear were the regions with the highest radiation dose received, followed by the back of the neck, left jaw, right jaw, and chin. The result of this study has shown the importance of DRL in Indonesia since the use of modern diagnostic imaging equipement that limits radiation dose to the minimum level is still very limited.

  19. Superficial skin ulcers

    International Nuclear Information System (INIS)

    Samaila, Modupeola O.; Rafindadi, Abdulmumini H.; Oluwole, Olabode P.; Adewuyi, Sunday A.

    2007-01-01

    Objective was to determine the underlying cause of superficial skin ulcers over a 15-year period. A retrospective histopathological analysis of 670 cases of superficial skin ulcers diagnosed in the Dept. of Pathology, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria from January 1991 to December 2005. A total of 670 superficial skin ulcers were analyzed. The mail to female gender ratio was 409:261(1.5:1.0) and a peakage frequency of 44.3 %( 297) in the 5th and 6th decades. Spectrum of lesions encountered was categorized into inflammatory, infections, benign and malignant diseases. The malignant lesions were 309 (46.1%), non-specific inflammation 302 (45.1%), granulation tissue 25 (3.7%) and pseudoepitheliomatous hyperplasia 14 (2.1%). A total of 18(2.7%) specific infections were encountered, which included bacterial, fungal and viral infection. Benign lesions were 2(0.3%), comprising of neurofibroma and Bowen's disease. The most common malignant lesion was squamous cell carcinoma 203 (30.3%) with a male to female ratio of 128:75 (1.7:1.0). Of these 161 were well differentiated tumors. The lower limb was the prevalent site distribution of all the ulcers. Superficial ulcers may be harbinger of malignant diseases. Squamous cell carcinoma remains the most common malignant lesion arising from chronic superficial ulcers from our setting. Adequate tissue biopsy and early diagnosis may reduce the attendant morbidity of these ulcers. (author)

  20. Plasma skin regeneration technology.

    Science.gov (United States)

    Bogle, M A

    2006-09-01

    Plasma skin regeneration (PSR) technology uses energy delivered from plasma rather than light or radiofrequency. Plasma is the fourth state of matter in which electrons are stripped from atoms to form an ionized gas. The plasma is emitted in a millisecond pulse to deliver energy to target tissue upon contact without reliance on skin chromophores. The technology can be used at varying energies for different depths of effect, from superficial epidermal sloughing to deeper dermal heating. With the Portrait PSR device (Rhytec, Inc.) there are three treatment guidelines termed PSR1, PSR2, and PSR3. The PSR1 protocol uses a series of low-energy treatments (1.0,1.2 Joules) spaced 3 weeks apart. The PSR2 protocol uses one high-energy pass (3.0, 4.0 Joules) performed in a single treatment, and the PSR3 protocol uses two high-energy passes (3.0 4.0 Joules) performed in a single treatment. All protocols improve fine lines, textural irregularities, and dyspigmentation; however, skin tightening is probably more pronounced with the high-energy treatments.

  1. Separation membrane development

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M.W. [Savannah River Technology Center, Aiken, SC (United States)

    1998-08-01

    A ceramic membrane has been developed to separate hydrogen from other gases. The method used is a sol-gel process. A thin layer of dense ceramic material is coated on a coarse ceramic filter substrate. The pore size distribution in the thin layer is controlled by a densification of the coating materials by heat treatment. The membrane has been tested by permeation measurement of the hydrogen and other gases. Selectivity of the membrane has been achieved to separate hydrogen from carbon monoxide. The permeation rate of hydrogen through the ceramic membrane was about 20 times larger than Pd-Ag membrane.

  2. Effects of radiation on the skin

    International Nuclear Information System (INIS)

    Hopewell, J.W.

    1985-01-01

    The effects of X-irradiation on pig skin are described, comparing and contrasting the effects seen in human and rodent skin. It is concluded that, anatomically, pig skin is the best animal model for human skin. The applications of the 'pig skin model' to investigations of the problems of radiation therapy and radiological protection of human skin are discussed. (U.K.)

  3. Interference of a short-chain phospholipid with ion transport pathways in frog skin

    DEFF Research Database (Denmark)

    Unmack, M A; Frederiksen, O; Willumsen, N J

    1997-01-01

    The effects of mucosal application of the short-chain phospholipid didecanoyl-L-alpha-phosphatidylcholine (DDPC; with two saturated 10-carbon acyl chains) on active Na+ transport and transepithelial conductance (G) in the frog skin (Rana temporaria) were investigated. Active Na+ transport...... of the frog skin epithelium and opens a paracellular tight junction pathway. Both effects may be caused by incorporation of DDPC in the apical cell membrane....

  4. Microporous silica membranes

    DEFF Research Database (Denmark)

    Boffa, Vittorio; Yue, Yuanzheng

    2012-01-01

    Hydrothermal stability is a crucial factor for the application of microporous silica-based membranes in industrial processes. Indeed, it is well established that steam exposure may cause densification and defect formation in microporous silica membranes, which are detrimental to both membrane...... permeability and selectivity. Numerous previous studies show that microporous transition metal doped-silica membranes are hydrothermally more stable than pure silica membranes, but less permeable. Here we present a quantitative study on the impact of type and concentration of transition metal ions...... on the microporous structure, stability and permeability of amorphous silica-based membranes, providing information on how to design chemical compositions and synthetic paths for the fabrication of silica-based membranes with a well accessible and highly stabile microporous structure....

  5. Clustering on Membranes

    DEFF Research Database (Denmark)

    Johannes, Ludger; Pezeshkian, Weria; Ipsen, John H

    2018-01-01

    Clustering of extracellular ligands and proteins on the plasma membrane is required to perform specific cellular functions, such as signaling and endocytosis. Attractive forces that originate in perturbations of the membrane's physical properties contribute to this clustering, in addition to direct...... protein-protein interactions. However, these membrane-mediated forces have not all been equally considered, despite their importance. In this review, we describe how line tension, lipid depletion, and membrane curvature contribute to membrane-mediated clustering. Additional attractive forces that arise...... from protein-induced perturbation of a membrane's fluctuations are also described. This review aims to provide a survey of the current understanding of membrane-mediated clustering and how this supports precise biological functions....

  6. Proposed derivation of skin contamination and skin decontamination limits

    International Nuclear Information System (INIS)

    Schieferdecker, H.; Koelzer, W.; Henrichs, K.

    1986-01-01

    From the primary dose limits for the skin, secondary dose limits were derived for skin contamination which can be used in practical radiation protection work. Analogous to the secondary dose limit for the maximum permissible body burden in the case of incorporation, dose limits for the 'maximum permissible skin burden' were calculated, with the help of dose factors, for application in the case of skin contamination. They can be derived from the skin dose limit values. For conditions in which the skin is exposed to temporary contamination, a limit of skin contamination was derived for immediately removable contamination and for one day of exposure. For non-removable contamination a dose limit of annual skin contamination was defined, taking into account the renewal of the skin. An investigation level for skin contamination was assumed, as a threshold, above which certain measures must be taken; these to include appropriate washing not more than three times, with the subsequent procedure determined by the level of residual contamination. The dose limits are indicated for selected radionuclides. (author)

  7. Application of dynamic membranes in anaerobic membranes in anaerobic membrane bioreactor systems

    NARCIS (Netherlands)

    Erşahin, M.E.

    2015-01-01

    Anaerobic membrane bioreactors (AnMBRs) physically ensure biomass retention by the application of a membrane filtration process. With growing application experiences from aerobic membrane bioreactors (MBRs), the combination of membrane and anaerobic processes has received much attention and become

  8. Skin substitutes for management of thermal burns in the event of a nuclear detonation

    International Nuclear Information System (INIS)

    Singh, Rita

    2014-01-01

    Skin substitutes can play a potential role in the treatment of burn injuries in a nuclear scenario. Defence Laboratory, Jodhpur is involved in the development of various types of skin substitutes for use in burn injuries. Amniotic membranes collected from placentae are processed as biological dressings and sterilized by gamma radiation. Multi-centric clinical trials have demonstrated the functional and clinical efficacy of radiation sterilized biological dressings in burn wound care. Chitin-nanosilver membranes and hydrogels have also been developed and characterized for use as burn wound dressing

  9. Skin moisturization mechanisms: new data.

    Science.gov (United States)

    Bonté, F

    2011-05-01

    The main function of the skin is to protect the body against exogenous substances and excessive water loss. The skin barrier is located in the outermost layer of the skin, called the stratum corneum, which is composed of corneocytes, originating from the keratinocytes differentiation process, embedded in organized complex lipid domains. Moisturizing of the skin is recognized as the first anti-aging skin care. Skin moisturization is essential for its appearance, protection, complexion, softness and the reinforcement of its barrier properties against deleterious and exogenous environmental factors. The intrinsic water binding capacity of skin is not only due to the complex natural moisturizing factor present in corneocytes, but also to hyaluronic acid and a regulated water transport within the skin. Recent data shows that the water movements between the cells at the different levels of the epidermis are due to dedicated water and glycerol transport proteins named aquaporins. Their role in the skin moisturization is completed by corneodesmosomes and tight junctions. Water and pH are now shown to be of prime importance in the regulation of the epidermal enzymes linked to corneocytes desquamation and lipid synthesis. Furthermore, the level of moisturization of the skin is important in its protection against repeated exposure to various irritant agents or phenomena such as very frequent washing with strong tensioactive materials. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  10. Probing lipid membrane electrostatics

    Science.gov (United States)

    Yang, Yi

    The electrostatic properties of lipid bilayer membranes play a significant role in many biological processes. Atomic force microscopy (AFM) is highly sensitive to membrane surface potential in electrolyte solutions. With fully characterized probe tips, AFM can perform quantitative electrostatic analysis of lipid membranes. Electrostatic interactions between Silicon nitride probes and supported zwitterionic dioleoylphosphatidylcholine (DOPC) bilayer with a variable fraction of anionic dioleoylphosphatidylserine (DOPS) were measured by AFM. Classical Gouy-Chapman theory was used to model the membrane electrostatics. The nonlinear Poisson-Boltzmann equation was numerically solved with finite element method to provide the potential distribution around the AFM tips. Theoretical tip-sample electrostatic interactions were calculated with the surface integral of both Maxwell and osmotic stress tensors on tip surface. The measured forces were interpreted with theoretical forces and the resulting surface charge densities of the membrane surfaces were in quantitative agreement with the Gouy-Chapman-Stern model of membrane charge regulation. It was demonstrated that the AFM can quantitatively detect membrane surface potential at a separation of several screening lengths, and that the AFM probe only perturbs the membrane surface potential by external field created by the internai membrane dipole moment. The analysis yields a dipole moment of 1.5 Debye per lipid with a dipole potential of +275 mV for supported DOPC membranes. This new ability to quantitatively measure the membrane dipole density in a noninvasive manner will be useful in identifying the biological effects of the dipole potential. Finally, heterogeneous model membranes were studied with fluid electric force microscopy (FEFM). Electrostatic mapping was demonstrated with 50 nm resolution. The capabilities of quantitative electrostatic measurement and lateral charge density mapping make AFM a unique and powerful

  11. Emulsification using microporous membranes

    Directory of Open Access Journals (Sweden)

    Goran T. Vladisavljević

    2011-10-01

    Full Text Available Membrane emulsification is a process of injecting a pure dispersed phase or pre-emulsion through a microporous membrane into the continuous phase. As a result of the immiscibility of the two phases, droplets of the dispersed phase are formed at the outlets of membrane pores. The droplets formed in the process are removed from the membrane surface by applying cross-flow or stirring of the continuous phase or using a dynamic (rotating or vibrating membrane. The most commonly used membrane for emulsification is the Shirasu Porous Glass (SPG membrane, fabricated through spinodal decomposition in a melt consisting of Japanese volcanic ash (Shirasu, boric acid and calcium carbonate. Microsieve membranes are increasingly popular as an alternative to highly tortuous glass and ceramic membranes. Microsieves are usually fabricated from nickel by photolithography and electroplating or they can be manufactured from silicon nitride via Reactive Ion Etching (RIE. An advantage of microsieves compared to the SPG membrane is in much higher transmembrane fluxes and higher tolerance to fouling by the emulsion ingredients due to the existence of short, straight through pores. Unlike conventional emulsification devices such as high-pressure valve homogenisers and rotor-stator devices, membrane emulsification devices permit a precise control over the mean pore size over a wide range and during the process insignificant amount of energy is dissipated as heat. The drop size is primarily determined by the pore size, but it depends also on other parameters, such as membrane wettability, emulsion formulation, shear stress on the membrane surface, transmembrane pressure, etc.

  12. Gyroid Nanoporous Membranes with Tunable Permeability

    DEFF Research Database (Denmark)

    Li, Li; Schulte, Lars; Clausen, Lydia D.

    2011-01-01

    -linked 1,2-polybutadiene (1,2-PB) membranes with uniform pores that, if needed, can be rendered hydrophilic. The gyroid porosity has the advantage of isotropic percolation with no need for structure prealignment. Closed (skin) or opened (nonskin) outer surface can be simply realized by altering...... the effective diffusion coefficients of a series of antibiotics, proteins, and other biomolecules; solute permeation is discussed in terms of hindered diffusion. The combination of uniform bulk morphology, isotropically percolating porosity, controlled surface chemistry, and tunable permeability is distinctive...

  13. Epidemiology of skin cancer.

    Science.gov (United States)

    Leiter, Ulrike; Eigentler, Thomas; Garbe, Claus

    2014-01-01

    Melanoma and nonmelanoma skin cancer (NMSC) are now the most common types of cancer in white populations. Both tumor entities show an increasing incidence rate worldwide but a stable or decreasing mortality rate. NMSC is the most common cancer in white-skinned individuals with a worldwide increasing incidence. NMSC is an increasing problem for health care services worldwide which causes significant morbidity. The rising incidence rates of NMSC are probably caused by a combination of increased exposure to ultraviolet (UV) or sun light, increased outdoor activities, changes in clothing style, increased longevity, ozone depletion, genetics and in some cases, immune suppression. An intensive UV exposure in childhood and adolescence was causative for the development of basal cell carcinoma (BCC) whereas for the etiology of SCC a chronic UV exposure in the earlier decades was accused. Cutaneous melanoma is the most rapidly increasing cancer in white populations, in the last 3 decades incidence rates have risen up to 5-fold. In 2008 melanoma was on place 5 in women and on place 8 in men of the most common solid tumor entities in Germany. The frequency of its occurrence is closely associated with the constitutive color of the skin, and the geographical zone. Changes in outdoor activities and exposure to sunlight during the past 50 years are an important factor for the increasing incidence of melanoma. Mortality rates of melanoma show a stabilization in the USA, Australia and also in European countries. In contrast to SCC, melanoma risk seems to be associated with an intermittent exposure to sunlight. Prevention campaigns aim on reducing incidence and achieving earlier diagnosis, which resulted in an ongoing trend toward thin melanoma since the last two decades. However, the impact of primary prevention measures on incidence rates of melanoma is unlikely to be seen in the near future, rather increasing incidence rates to 40-50/100,000 inhabitants/year should be expected in

  14. Evaluation of the mechanism of skin enhancing surfactants on the biomembrane of shed snake skin.

    Science.gov (United States)

    Wonglertnirant, Nanthida; Ngawhirunpat, Tanasait; Kumpugdee-Vollrath, Mont

    2012-01-01

    The aim of the present work was to investigate the effects of different surfactants at various concentrations as a skin penetration enhancer through the biomembrane of the shed skin of Naja kaouthia. Additionally, the enhancer mechanism(s) of each class of surfactants were evaluated using physical characterization techniques, such as scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, and small and wide angle X-ray scattering (SWAXS). Our results showed that skin permeability increased with increasing concentrations of surfactants and the degree of increase was higher for the model hydrophilic permeant, deuterium dioxide (D(2)O), than the lipophilic permeant, ketoprofen (KP). Ionic surfactants, sodium lauryl sulfate (SLS) and cetyl trimethyl ammonium bromide (CTAB), demonstrated higher enhancement ability than the polyoxyethylene (20) sorbitan mono-oleate (Tween 80) non-ionic surfactant, which was consistent with the results from physical characterization studies. Increasing amounts of permeated drug resulted in an increase in membrane interactions. From our observations, it can be assumed that SLS and CTAB can be localized inside the biomembrane and thereby enhance drug permeation mainly through interactions with intercellular lipids in the stratum corneum (SC) and the creation of a perturbed microenvironment among lipid alkyl chains and polar head groups.

  15. Skin tightening technologies.

    Science.gov (United States)

    Greene, Ryan M; Green, Jeremy B

    2014-02-01

    Radiofrequency (RF) and intense focused ultrasound (IFUS) are increasingly used to address skin laxity of the face and neck. Both nonablative RF and ultrasound create a heat-induced tissue response that leads to collagen remodeling and other ultrastructural changes. Although these treatments are not meant to replace surgical procedures, patient satisfaction in the majority of studies has been consistently high. This article discusses the various RF and IFUS technologies currently in use and reviews pertinent clinical studies evaluating their efficacy and safety. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  16. On the subtle balance between competitive sorption and plasticization effects in asymmetric hollow fiber gas separation membranes

    NARCIS (Netherlands)

    Visser, Tymen; Koops, G.H.; Wessling, Matthias

    2005-01-01

    The paper describes the influence of a varying feed composition of CO2/CH4 and CO2/N2 mixtures on the gas separation performance of integrally skinned asymmetric PES/PI hollow fibers with an effective skin thickness of 0.27 ¿m. Normally, thin membrane structures (<3 ¿m) show accelerated

  17. Human skin in vitro permeation of bentazon and isoproturon formulations with or without protective clothing suit.

    Science.gov (United States)

    Berthet, Aurélie; Hopf, Nancy B; Miles, Alexandra; Spring, Philipp; Charrière, Nicole; Garrigou, Alain; Baldi, Isabelle; Vernez, David

    2014-01-01

    Skin exposures to chemicals may lead, through percutaneous permeation, to a significant increase in systemic circulation. Skin is the primary route of entry during some occupational activities, especially in agriculture. To reduce skin exposures, the use of personal protective equipment (PPE) is recommended. PPE efficiency is characterized as the time until products permeate through material (lag time, Tlag). Both skin and PPE permeations are assessed using similar in vitro methods; the diffusion cell system. Flow-through diffusion cells were used in this study to assess the permeation of two herbicides, bentazon and isoproturon, as well as four related commercial formulations (Basagran(®), Basamais(®), Arelon(®) and Matara(®)). Permeation was measured through fresh excised human skin, protective clothing suits (suits) (Microchem(®) 3000, AgriSafe Pro(®), Proshield(®) and Microgard(®) 2000 Plus Green), and a combination of skin and suits. Both herbicides, tested by itself or as an active ingredient in formulations, permeated readily through human skin and tested suits (Tlag < 2 h). High permeation coefficients were obtained regardless of formulations or tested membranes, except for Microchem(®) 3000. Short Tlag, were observed even when skin was covered with suits, except for Microchem(®) 3000. Kp values tended to decrease when suits covered the skin (except when Arelon(®) was applied to skin covered with AgriSafe Pro and Microgard(®) 2000), suggesting that Tlag alone is insufficient in characterizing suits. To better estimate human skin permeations, in vitro experiments should not only use human skin but also consider the intended use of the suit, i.e., the active ingredient concentrations and type of formulations, which significantly affect skin permeation.

  18. Impacts of operating conditions and solution chemistry on osmotic membrane structure and performance

    KAUST Repository

    Wong, Mavis C.Y.

    2012-02-01

    Herein, we report on changes in the performance of a commercial cellulose triacetate (CTA) membrane, imparted by varied operating conditions and solution chemistries. Changes to feed and draw solution flow rate did not significantly alter the CTA membrane\\'s water permeability, salt permeability, or membrane structural parameter when operated with the membrane skin layer facing the draw solution (PRO-mode). However, water and salt permeability increased with increasing feed or draw solution temperature, while the membrane structural parameter decreased with increasing draw solution, possibly due to changes in polymer intermolecular interactions. High ionic strength draw solutions may de-swell the CTA membrane via charge neutralization, which resulted in lower water permeability, higher salt permeability, and lower structural parameter. This observed trend was further exacerbated by the presence of divalent cations which tends to swell the polymer to a greater extent. Finally, the calculated CTA membrane\\'s structural parameter was lower and less sensitive to external factors when operated in PRO-mode, but highly sensitive to the same factors when the skin layer faced the feed solution (FO-mode), presumably due to swelling/de-swelling of the saturated porous substructure by the draw solution. This is a first attempt aimed at systematically evaluating the changes in performance of the CTA membrane due to operating conditions and solution chemistry, shedding new insight into the possible advantages and disadvantages of this material in certain applications. © 2011 Elsevier B.V.

  19. Contamination and decontamination of skin

    International Nuclear Information System (INIS)

    Severa, J.; Knajfl, J.

    1983-01-01

    In external contamination the beta radiation dose is the prevalent component of the total dose absorbed by the skin. There exist four types of radionUclide bonds to the skin: mechanical retention of solid particles or solution on the surface and in the pores, physical adsorption of nondissociated molecules or colloids, the ion exchange effect, and chemisorption. Radionuclides then penetrate the skin by transfollicular transfer. The total amount of radioactive substances absorbed into the skin depends on the condition of the skin. Skin is decontaminated by washing with lukewarm water and soap or with special decontamination solutions. The most widely used components of decontamination solutions are detergents, chelaton, sodium hexametaphosphate, oxalic acid, citric acid. The main principles of the decontamination of persons are given. (M.D.)

  20. Ion-conducting membranes

    Science.gov (United States)

    Masel, Richard I.; Sajjad, Syed Dawar; Gao, Yan; Liu, Zengcai; Chen, Qingmei

    2017-12-26

    An anion-conducting polymeric membrane comprises a terpolymer of styrene, vinylbenzyl-R.sub.s and vinylbenzyl-R.sub.x. R.sub.s is a positively charged cyclic amine group. R.sub.x is at least one constituent selected from the group consisting Cl, OH and a reaction product between an OH or Cl and a species other than a simple amine or a cyclic amine. The total weight of the vinylbenzyl-R.sub.x groups is greater than 0.3% of the total weight of the membrane. In a preferred embodiment, the membrane is a Helper Membrane that increases the faradaic efficiency of an electrochemical cell into which the membrane is incorporated, and also allows product formation at lower voltages than in cells without the Helper Membrane.

  1. Gas separation with membranes

    International Nuclear Information System (INIS)

    Schulz, G.; Michele, H.; Werner, U.

    1982-01-01

    Gas separation with membranes has already been tested in numerous fields of application, e.g. uranium enrichment of H 2 separation. In many of these processes the mass transfer units, so-called permeators, have to be connected in tandem in order to achieve high concentrations. A most economical operating method provides for each case an optimization of the cascades with regard to the membrane materials, construction and design of module. By utilization of the concentration gradient along the membrane a new process development has been accomplished - the continuously operating membrane rectification unit. Investment and operating costs can be reduced considerably for a number of separating processes by combining a membrane rectification unit with a conventional recycling cascade. However, the new procedure requires that the specifications for the module construction, flow design, and membrane properties be reconsidered. (orig.) [de

  2. Nicotinic acid receptor abnormalities in human skin cancer: implications for a role in epidermal differentiation.

    Directory of Open Access Journals (Sweden)

    Yira Bermudez

    Full Text Available Chronic UV skin exposure leads to epidermal differentiation defects in humans that can be largely restored by pharmacological doses of nicotinic acid. Nicotinic acid has been identified as a ligand for the human G-protein-coupled receptors GPR109A and GPR109B that signal through G(i-mediated inhibition of adenylyl cyclase. We have examined the expression, cellular distribution, and functionality of GPR109A/B in human skin and skin derived epidermal cells.Nicotinic acid increases epidermal differentiation in photodamaged human skin as judged by the terminal differentiation markers caspase 14 and filaggrin. Both GPR109A and GPR109B genes are transcribed in human skin and in epidermal keratinocytes, but expression in dermal fibroblasts is below limits of detection. Receptor transcripts are greatly over-expressed in squamous cell cancers. Receptor protein in normal skin is prominent from the basal through granular layers of the epidermis, with cellular localization more dispersive in the basal layer but predominantly localized at the plasma membrane in more differentiated epidermal layers. In normal human primary and immortalized keratinocytes, nicotinic acid receptors show plasma membrane localization and functional G(i-mediated signaling. In contrast, in a squamous cell carcinoma derived cell line, receptor protein shows a more diffuse cellular localization and the receptors are nearly non-functional.The results of these studies justify future genetic and pharmacological intervention studies to define possible specific role(s of nicotinic acid receptors in human skin homeostasis.

  3. Chelating polymeric membranes

    KAUST Repository

    Peinemann, Klaus-Viktor

    2015-01-22

    The present application offers a solution to the current problems associated with recovery and recycling of precious metals from scrap material, discard articles, and other items comprising one or more precious metals. The solution is premised on a microporous chelating polymeric membrane. Embodiments include, but are not limited to, microporous chelating polymeric membranes, device comprising the membranes, and methods of using and making the same.

  4. Skin contamination - prevention and decontaminating

    International Nuclear Information System (INIS)

    Henning, K.

    2001-01-01

    A detailed examination is made of the structure of human skin. Measures were drawn up to prevent skin contamination in nuclear installations as well as contaminated skin was decontaminated from the personnel. By systematically applying these measures a significant level of success was achieved in preventing contamination in nuclear installations. Cases where more far-reaching chemical methods had to be used were kept to a minimum. (R.P.)

  5. Protecting the skin during thyroidectomy

    Directory of Open Access Journals (Sweden)

    Renan Bezerra Lira

    Full Text Available In this note we describe the standard technical maneuver used in our department to protect the skin during thyroidectomy in order to get the best aesthetic result. We use surgical gloves to protect the skin during these operations to reduce the negative impact of thermal trauma and mechanical retractors and energy delivery devices at the edges of the skin incised. This practice is effective, inexpensive, rapid, reproducible and showed no complication in our experience of over 2,500 thyroidectomies.

  6. Neutron Skins and Neutron Stars

    OpenAIRE

    Piekarewicz, J.

    2013-01-01

    The neutron-skin thickness of heavy nuclei provides a fundamental link to the equation of state of neutron-rich matter, and hence to the properties of neutron stars. The Lead Radius Experiment ("PREX") at Jefferson Laboratory has recently provided the first model-independence evidence on the existence of a neutron-rich skin in 208Pb. In this contribution we examine how the increased accuracy in the determination of neutron skins expected from the commissioning of intense polarized electron be...

  7. Source and destination memory: two sides of the same coin?

    Science.gov (United States)

    Lindner, Isabel; Drouin, Héloïse; Tanguay, Annick F N; Stamenova, Vessela; Davidson, Patrick S R

    2015-01-01

    Whereas source memory involves remembering from whom you have heard something, destination memory involves remembering to whom you have told something. Despite its practical relevance, destination memory has been studied little. Recently, two reports suggested that generally destination memory should be poorer than source memory, and that it should be particularly difficult for older people. We tested these predictions by having young and older participants read sentences to two examiners (destination encoding) and listen to sentences read by two examiners (source encoding), under intentional (Experiment 1) or incidental encoding (Experiments 2 and 3). Only in Experiment 3 (in which cognitive demands during destination encoding were increased) was destination memory significantly poorer than source memory. In none of the experiments were older adults inferior to the young on destination or source memory. Destination- and source-memory scores were significantly correlated. Item memory was consistently superior for sentences that had been read out loud (during destination encoding) versus those that had been heard (during source encoding). Destination memory needs not always be poorer than source memory, appears not to be particularly impaired by normal ageing and may depend on similar processes to those supporting source memory.

  8. TNF and cancer: the two sides of the coin.

    Science.gov (United States)

    Mocellin, Simone; Nitti, Donato

    2008-01-01

    Despite its name, discovery history and approval as anticancer agent, tumor necrosis factor (TNF) has been implicated in both cancer development and progression in some preclinical models. In particular, as a central mediator of inflammation, TNF might represent one of the molecular links between chronic inflammation and the subsequent development of malignant disease. Furthermore, deregulated TNF expression within the tumor microenvironment appears to favor malignant cell tissue invasion, migration and ultimately metastasis formation. On the other side, TNF clearly possesses antitumor effects not only in preclinical models but also in the clinical setting. In order to reconcile these conflicting findings, we provide readers with an overview on the most relevant available evidence supporting anticancer as well as cancer-promoting TNF effects; on the basis of these data, we propose a model to explain the coexistence of these apparently paradoxical TNF activities.

  9. Extreme poverty and affluence, the two sides of our world

    International Nuclear Information System (INIS)

    Bischoff, G.

    1987-01-01

    The author discusses the different economic situtions in the industrialized and in the developing parts of the world, and the resulting fears of the populations. These feelings of fear and apprehension are traced back to their manifold causes, discussing among others unsecure raw material supply and the damage to the environment, hostile attitudes towards industrial exploitation or technical sciences, the role of the press and other media in the 'making' of fear of life, the fear of becoming slave of the machines. The problems' solution lies in the supply and utilisation of energy, and any efforts towards maintaining our natural environment so that life may go on will have to be based, the author says, on the technological development from nuclear power to thermonuclear fusion. (HSCH) [de

  10. [Diet and gut microbiota: two sides of the same coin?

    Science.gov (United States)

    Schiumerini, Ramona; Pasqui, Francesca; Festi, Davide

    2018-01-01

    Gut microbiota is a complex ecosystem, resident in the digestive tract, exerting multiple functions that can have a significant impact on the pathophysiology of the host organism. The composition and functions of this "superorganism" are influenced by many factors, and among them, the host's dietary habits seem to have a significant effect. Dietary changes in the evolution of human history and in the different stages of life of the human subjects are responsible for qualitative and functional modification of gut microbiota. At the same time, the different dietary models adopted in worldwide geographic areas take into account the inter-individual differences concerning composition and microbial function. This close relationship between diet, gut microbiota and host seems, in fact, to be responsible for the protection or predisposition to develop several metabolic, immunological, neoplastic and functional diseases. Thus, several studies have evaluated the impact of diet and lifestyle modification strategies on gut microbiota composition and functions which, in turn, seems to affect the effectiveness of such therapeutic measures. Gut microbiota manipulation strategies, as complementary to dietary modifications, represent a fascinating field of research, even if consolidated data are still lacking.

  11. Meditation and Hypnosis: Two Sides of the Same Coin?

    Science.gov (United States)

    Facco, Enrico

    2017-01-01

    Hypnosis and meditation, as a whole, form a heterogeneous complex of psychosomatic techniques able to control mind and body regulation. Hypnosis has been pragmatically used for limited therapeutic targets, while Eastern meditation has much wider philosophical and existential implications, aiming for a radical liberation from all illusions, attachments, suffering and pain. The available data on the history, phenomenology, and neuropsychology of hypnosis and meditation show several common features, such as the following: (a) induction based on focused attention; (b) capability to reach an intentional control of both biologic-somatic activities and conscious-unconscious processes; (c) activation/deactivation of several brain areas and circuits (e.g., the default modality network and pain neuromatrix) with a relevant overlapping between the two.

  12. Suppression and belief revision, two sides of the same coin?

    Directory of Open Access Journals (Sweden)

    Kristien Dieussaert

    2005-03-01

    Full Text Available This paper examines three experimental paradigms, designed for common sense reasoning. The comparison regards the effect disablers and alternatives exercise on the data. It was previously shown that alternatives and disablers influence the reasoning process in the three experimental paradigms: the Inference paradigm (e.g., Cummins et al., 1991, the Suppression paradigm (e.g., Byrne, 1989 and the Belief Revision paradigm (e.g., Elio, 1997. However, they were never directly compared due to large variations in the pragmatic type of conditionals and in the answer format. With this paper, we hope to fill this gap as we provide a direct comparison of the paradigms to gain more insight in reasoning with inconsistencies.

  13. Mitochondrial genome and epigenome: two sides of the same coin.

    Science.gov (United States)

    D'Aquila, Patrizia; Montesanto, Alberto; Guarasci, Francesco; Passarino, Giuseppe; Bellizzi, Dina

    2017-01-01

    The involvement of mitochondrial content, structure and function as well as of the mitochondrial genome (mtDNA) in cell biology, by participating in the main processes occurring in the cells, has been a topic of intense interest for many years. More specifically, the progressive accumulation of variations in mtDNA of post-mitotic tissues represents a major contributing factor to both physiological and pathological phenotypes. Recently, an epigenetic overlay on mtDNA genetics is emerging, as demonstrated by the implication of the mitochondrial genome in the regulation of the intracellular epigenetic landscape being itself object of epigenetic modifications. Indeed, in vitro and population studies strongly suggest that, similarly to nuclear DNA, also mtDNA is subject to methylation and hydroxymethylation. It follows that the mitochondrial-nucleus cross talk and mitochondrial retrograde signaling in cellular properties require a concerted functional cooperation between genetic and epigenetic changes. The present paper aims to review the current advances in mitochondrial epigenetics studies and the increasing indication of mtDNA methylation status as an attractive biomarker for peculiar pathological phenotypes and environmental exposure.

  14. Two Sides of the Same Coin: Politics in the Classroom

    Science.gov (United States)

    Berg, Steven L.

    2005-01-01

    This paper presents interviews with David Horowitz, an author, professor, and President of the Center for the Study of Popular Culture headquartered in Los Angeles, California and Carol King, an adjunct professor of theology at Xavier University in Cincinnati, Ohio, and manager of the Cinergy Foundation, also in Cincinnati. The interviews present…

  15. Two Sides of the Same Coin: Authentic Assessment

    Science.gov (United States)

    Berg, Steven L.

    2006-01-01

    This paper presents interviews with Dr. Jon Mueller and Dr. Paula Harris. Dr. Jon Mueller is a professor of Psychology at North Central College in Naperville, Illinois. Dr. Paula Harris is a professor in the Department of Language, Literature, and Arts at Jackson Community College in Jackson, Michigan. In these interviews, they present a…

  16. Two Sides of the Same Coin: Faculty Doing Research

    Science.gov (United States)

    Berg, Steven L.

    2006-01-01

    Dr. Richard Sagor is the Educational Leadership Program Director and a professor in the Department of Education at Lewis & Clark College in Portland, Oregon. Dr. Howard Tinberg is a professor of English at Bristol Community College in Fall River, Massachusetts, where he is also director of the Writing Lab. He is the editor of the journal…

  17. An ingested foreign body: two sides of the same coin?

    Science.gov (United States)

    Varadharajan, Kiran; Magill, Jennifer; Patel, Kalpesh

    2014-04-09

    A 2-year-old child presented to the emergency department with an acute onset of dysphagia and stertor. A plain anteroposterior chest X-ray revealed a single circular opacity in the middle third of the oesophagus consistent with an ingested coin. The child was taken to the theatre for rigid pharyngo-oesophagoscopy and removal of the coin. After the first coin was removed subsequent endoscopic examination revealed a second coin at the same location. This extremely rare case of two ingested coins becoming impacted with perfect radiological alignment emphasises the importance of thorough examination on endoscopy and the potential limitations of an X-ray in initial assessment of an ingested foreign body.

  18. Two Sides of the Same Coin: Reaching Nontraditional Students

    Science.gov (United States)

    Berg, Steven L.

    2005-01-01

    This paper presents interviews with Barbara Bonham, a Senior Researcher at the National Center for Developmental Education and a member of the faculty at the Kellogg Institute, Appalachian State University in Boone, North Carolina and Melanie Chu, the Outreach Librarian at Cal State San Marcos in San Marcos, California. In these interviews they…

  19. Venous and Arterial Thromboses: Two Sides of the Same Coin?

    Science.gov (United States)

    Lippi, Giuseppe; Favaloro, Emmanuel J

    2018-04-01

    Arterial and venous thromboses are sustained by development of intraluminal thrombi, respectively, within the venous and arterial systems. The composition and structure of arterial and venous thrombi have been historically considered as being very different. Arterial thrombi (conventionally defined as "white") have been traditionally proposed to be composed mainly of fibrin and platelet aggregates, whilst venous thrombi (conventionally defined as "red") have been proposed as mostly being enriched in fibrin and erythrocytes. This archaic dichotomy seems ever more questionable, since it barely reflects the pathophysiology of thrombus formation in vivo. Both types of thrombi are actually composed of a complex fibrin network but, importantly, also contain essentially the same blood-borne cells (i.e., red blood cells, leukocytes, and platelets), and it is only the relative content of these individual elements that differ between venous and arterial clots or, otherwise, between thrombi generated under different conditions of blood flow and shear stress. Convincing evidence now suggests that either white or red intracoronary thrombi may be present in patients with myocardial infarction and, even more importantly, red thrombi may be more prone to distal embolization during percutaneous coronary intervention than those with lower content of erythrocytes. Conversely, it is now accepted that components traditionally considered to be involved "only" in arterial thrombosis are also represented in venous thrombosis. Thus, platelets comprise important components of venous clots, although they may be present in lower amounts here than in arterial thrombi, and von Willebrand factor is also represented in both arterial and venous thrombi. Of importance, such evidence thus supports the concept that adjunctive treatment normally associated to prevention of arterial thrombosis (e.g., aspirin) may have a role also in prevention and treatment of venous thrombosis. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  20. Autoimmunity and primary immunodeficiency: two sides of the same coin?

    Science.gov (United States)

    Schmidt, Reinhold E; Grimbacher, Bodo; Witte, Torsten

    2017-12-19

    Autoimmunity and immunodeficiency were previously considered to be mutually exclusive conditions; however, increased understanding of the complex immune regulatory and signalling mechanisms involved, coupled with the application of genetic analysis, is revealing the complex relationships between primary immunodeficiency syndromes and autoimmune diseases. Single-gene defects can cause rare diseases that predominantly present with autoimmune symptoms. Such genetic defects also predispose individuals to recurrent infections (a hallmark of immunodeficiency) and can cause primary immunodeficiencies, which can also lead to immune dysregulation and autoimmunity. Moreover, risk factors for polygenic rheumatic diseases often exist in the same genes as the mutations that give rise to primary immunodeficiency syndromes. In this Review, various primary immunodeficiency syndromes are presented, along with their pathogenetic mechanisms and relationship to autoimmune diseases, in an effort to increase awareness of immunodeficiencies that occur concurrently with autoimmune diseases and to highlight the need to initiate appropriate genetic tests. The growing knowledge of various genetically determined pathologic mechanisms in patients with immunodeficiencies who have autoimmune symptoms opens up new avenues for personalized molecular therapies that could potentially treat immunodeficiency and autoimmunity at the same time, and that could be further explored in the context of autoimmune rheumatic diseases.

  1. Multiculturalism and Social Justice: Two Sides of the Same Coin

    Science.gov (United States)

    Ratts, Manivong J.

    2011-01-01

    The development of multicultural and advocacy competencies evolved out of the multicultural and social justice movements. To help readers more fully understand the complementary nature between these 2 sets of competencies and to connect both movements, this article introduces the Multicultural and Advocacy Dimensions model. Implications are also…

  2. Acute Hepatitis E: Two Sides of the Same Coin.

    Science.gov (United States)

    Hartl, Johannes; Wehmeyer, Malte H; Pischke, Sven

    2016-11-03

    The relevance of acute hepatitis E virus (HEV) infections has been underestimated for a long time. In the past, HEV infection had been interpreted falsely as a disease limited to the tropics until the relevance of autochthonous HEV infections in the Western world became overt. Due to increased awareness, the incidence of diagnosed autochthonous HEV infections (predominantly genotype 3) in industrialized countries has risen within the last decade. The main source of infections in industrialized countries seems to be infected swine meat, while infections with the tropical HEV genotypes 1 and 2 usually are mainly transmitted fecal-orally by contaminated drinking water. In the vast majority of healthy individuals, acute HEV infection is either clinically silent or takes a benign self-limited course. In patients who develop a symptomatic HEV infection, a short prodromal phase with unspecific symptoms is followed by liver specific symptoms like jaundice, itching, uncoloured stool and darkened urine. Importantly, tropical HEV infections may lead to acute liver failure, especially in pregnant women, while autochthonous HEV infections may lead to acute-on-chronic liver failure in patients with underlying liver diseases. Immunosuppressed individuals, such as transplant recipients or human immunodeficiency virus (HIV)-infected patients, are at risk for developing chronic hepatitis E, which may lead to liver fibrosis and cirrhosis in the long term. Importantly, specific treatment options for hepatitis E are not approved by the regulation authorities, but off-label ribavirin treatment seems to be effective in the treatment of chronic HEV-infection and may reduce the disease severity in patients suffering from acute liver failure.

  3. Multimorbidity or polypharmacy: two sides of the same coin?

    Directory of Open Access Journals (Sweden)

    Carol Sinnott

    2015-04-01

    Full Text Available Polypharmacy, broadly defined as the chronic co-prescription of several drugs [1], has long been recognized as problematic. The greater the number of medicines a patient takes, the greater the risk of adverse effects of any one medicine, and the greater the risk of drug–drug interactions. Thus, polypharmacy is an accepted risk for poor health outcomes, including hospitalizations and mortality [2]. The number of drugs per patient (or polypharmacy has come to be used as a measure of potentially hazardous professional behaviour, and is sometimes used in conjunction with the term ‘inappropriate prescribing’. Nonetheless, the prevalence of polypharmacy is rising inexorably [3]. This rise is driven, principally, by the rising prevalence of multimorbidity, i.e. the co-occurrence of two or more chronic long-term diseases or conditions in one patient [4]. The issue is compounded by clinical guidelines that advocate the use of several medicines in the management of individual diseases and their associated risk factors [5]. The result is a dilemma for prescribers: on the one hand there is the need to keep the number of medicines to a minimum, while on the other ensuring that the patient receives what evidence-based guidelines advocate as being in their best interest [6].

  4. Hormesis: Decoding Two Sides of the Same Coin

    Directory of Open Access Journals (Sweden)

    Dipita Bhakta-Guha

    2015-12-01

    Full Text Available In the paradigm of drug administration, determining the correct dosage of a therapeutic is often a challenge. Several drugs have been noted to demonstrate contradictory effects per se at high and low doses. This duality in function of a drug at different concentrations is known as hormesis. Therefore, it becomes necessary to study these biphasic functions in order to understand the mechanistic basis of their effects. In this article, we focus on different molecules and pathways associated with diseases that possess a duality in their function and thus prove to be the seat of hormesis. In particular, we have highlighted the pathways and factors involved in the progression of cancer and how the biphasic behavior of the molecules involved can alter the manifestations of cancer. Because of the pragmatic role that it exhibits, the imminent need is to draw attention to the concept of hormesis. Herein, we also discuss different stressors that trigger hormesis and how stress-mediated responses increase the overall adaptive response of an individual to stress stimulus. We talk about common pathways through which cancer progresses (such as nuclear factor erythroid 2-related factor 2-Kelch-like ECH-associated protein 1 (Nrf2-Keap1, sirtuin-forkhead box O (SIRT-FOXO and others, analyzing how diverse molecules associated with these pathways conform to hormesis.

  5. NF-kappaB: Two Sides of the Same Coin.

    Science.gov (United States)

    Pires, Bruno R B; Silva, Rafael C M C; Ferreira, Gerson M; Abdelhay, Eliana

    2018-01-09

    Nuclear Factor-kappa B (NF-κB) is a transcription factor family that regulates a large number of genes that are involved in important physiological processes, including survival, inflammation, and immune responses. More recently, constitutive expression of NF-κB has been associated with several types of cancer. In addition, microorganisms, such as viruses and bacteria, cooperate in the activation of NF-κB in tumors, confirming the multifactorial role of this transcription factor as a cancer driver. Recent reports have shown that the NF-κB signaling pathway should receive attention for the development of therapies. In addition to the direct effects of NF-κB in cancer cells, it might also impact immune cells that can both promote or prevent tumor development. Currently, with the rise of cancer immunotherapy, the link among immune cells, inflammation, and cancer is a major focus, and NF-κB could be an important regulator for the success of these therapies. This review discusses the contrasting roles of NF-κB as a regulator of pro- and antitumor processes and its potential as a therapeutic target.

  6. Acetylcholine, Histamine, and Cognition: Two Sides of the Same Coin

    Science.gov (United States)

    Blandina, Patrizio; Efoudebe, Marcel; Cenni, Gabriele; Mannaioni, Pierfrancesco; Passani, Maria Beatrice

    2004-01-01

    The forebrain cholinergic neurons are localized in the nucleus basalis magnocellularis (NBM), the major source of cholinergic innervation to the neocortex and to the amygdala, and in the medium septum-banda diagonalis complex, which provides cholinergic inputs to the hippocampus (Mesulam et al. 1983; Woolf et al. 1984; Nicoll 1985). Basic and…

  7. Young successors : A Two-Sided Story in Renewing SMEs

    NARCIS (Netherlands)

    Karin Kleingeld; Lex van Teeffelen

    2016-01-01

    Entrepreneurship is often used as a synonym for starting up a new business. Existing SMEs — from purchasing to succession — are all too often left out of the picture. This booklet tells the stories of those involved in handing over their businesses to the next generation. It’s an honest and

  8. Belief and unbelief: two sides of a coin

    Directory of Open Access Journals (Sweden)

    Grace Davie

    2012-06-01

    Full Text Available In what follows I build on to previous writing relating to the nature of religion (including religious belief in modern Europe and the factors that must be taken into account if this is to be properly understood (Davie 1994, 2000, 2002, 2006. These factors are: •the cultural heritage of Europe; •the ‘old’ model of a moderately dominant state church which operates like a public utility; •a ‘newer’ model which takes the form of a growing market in religion; •the arrival into Europe of new groups of people both Christian and other; •an increasingly articulate secular lobby. The first point to grasp is that all five exist alongside each other and that they push and pull in different directions. The second point provides the focus for this article: namely that exactly the same factors that account for the nature of religious belief in European society are equally present in unbelief. I will take each of them in turn in order to illustrate this point.

  9. PRIVATIZATION OF BRAZILIAN PRISONS: THE TWO SIDES OF THE CURRENCY

    Directory of Open Access Journals (Sweden)

    Hilderline Câmara de Oliveira

    2017-09-01

    Full Text Available Since the beginning of the 1990s, in Brazil, privatization has proved to be an emergency exit to crisis of services that the State cannot offer efficiently, such as Education, Health, Transportation, and more recently Social Security. The agenda in question is now Public Safety. Failing to meet the demand for lawsuits that pass through the Judiciary, Brazilian prisons are becoming increasingly overcrowded; the services lagged; Constant rebellions, high crime rate, denial of human rights and structural violence, glaring. Thus, this article aims to reflect on both sides of the 'currency' of prisons privatizations in the Brazilian scenario. He used the research with a qualitative approach and bibliographical character with the support of theoretical references from the specialized literature in the area, besides the technical documents, official reports from the Government and NGOs that carry out social control works. The research has shown that privatization seems to be the best way out in the short term and can solve a number of social problems, but how can one think of the profitable return that all privatization requires if its main objective is to reduce the target population? So either this alternative will create a market that, if it turns out, will end itself, or we will end up creating an even more perverse logic of incarceration.

  10. Quantizing the electromagnetic field near two-sided semitransparent mirrors

    Science.gov (United States)

    Furtak-Wells, Nicholas; Clark, Lewis A.; Purdy, Robert; Beige, Almut

    2018-04-01

    This paper models light scattering through flat surfaces with finite transmission, reflection, and absorption rates, with wave packets approaching the mirror from both sides. While using the same notion of photons as in free space, our model also accounts for the presence of mirror images and the possible exchange of energy between the electromagnetic field and the mirror surface. To test our model, we derive the spontaneous decay rate and the level shift of an atom in front of a semitransparent mirror as a function of its transmission and reflection rates. When considering limiting cases and using standard approximations, our approach reproduces well-known results but it also paves the way for the modeling of more complex scenarios.

  11. Dematerialization and capital maintenance. Two sides of the sustainability coin

    Energy Technology Data Exchange (ETDEWEB)

    Bartelmus, Peter [Wuppertal Institute, Doppersberg 19, D-42103 Wuppertal (Germany)

    2003-08-01

    The reductionist trend of equating sustainable development with sustained economic growth needs to be reversed. New accounts and balances help to operationalize the elusive notion of sustainability: they provide a coherent picture of the interaction between environment and economy. 'Greened' national accounts measure economic sustainability in terms of (produced and natural) capital maintenance; balances of material flows assess ecological sustainability as the dematerialization of production and consumption. Both concepts aim to preserve environmental assets, but differ in scope, strength and evaluation of sustainability. First results for Germany indicate weak sustainability of the economy; strong sustainability is not in sight because of insufficient reduction of material throughput. Attaining sustainability through integrated policies needs the support of share- and stakeholders of sustainable development.

  12. Refeeding and metabolic syndromes: two sides of the same coin

    Science.gov (United States)

    Obeid, O A; Hachem, D H; Ayoub, J J

    2014-01-01

    Refeeding syndrome describes the metabolic and clinical changes attributed to aggressive rehabilitation of malnourished subjects. The metabolic changes of refeeding are related to hypophosphatemia, hypokalemia, hypomagnesemia, sodium retention and hyperglycemia, and these are believed to be mainly the result of increased insulin secretion following high carbohydrate intake. In the past few decades, increased consumption of processed food (refined cereals, oils, sugar and sweeteners, and so on) lowered the intake of several macrominerals (mainly phosphorus, potassium and magnesium). This seems to have compromised the postprandial status of these macrominerals, in a manner that mimics low grade refeeding syndrome status. At the pathophysiological level, this condition favored the development of the different components of the metabolic syndrome. Thus, it is reasonable to postulate that metabolic syndrome is the result of long term exposure to a mild refeeding syndrome. PMID:24979149

  13. Areeda-Turner in Two-Sided Markets

    NARCIS (Netherlands)

    Behringer, S.; Filistrucchi, L.

    2014-01-01

    Areeda and Turner (1975) were the first to argue that a price below marginal costs should be considered a sign of predation. Recognizing that marginal cost data were typically unavailable, the authors concluded that a price below average variable cost should be presumed unlawful. This socalled

  14. Beneficial and Harmful Addictions: Two sides of the same coin

    Directory of Open Access Journals (Sweden)

    Rafael López

    2016-01-01

    Full Text Available En este artículo obtenemos un isomorfismo entre las adicciones beneficiosas y las perjudiciales en un contexto de elección binaria en tiempo discreto. La equivalencia obtenida de este modo nos permite estudiar los dos fenómenos (los dos tipos de adicciones como dos caras de la misma moneda. Además de la visión teórica que proporciona, esta dualidad también resulta particularmente útil porque permite trasladar fácilmente los resultados obtenidos en el campo de las adicciones perjudiciales al campo de las adicciones beneficiosas. Una vez establecido el dualismo, analizamos las adicciones bajo dos tipos de preferencias intertemporales: aquellas que son consistentes y aquellas que no lo son.

  15. Two Sides of the Megalopolis: Educating for Sustainable Citizenship

    Directory of Open Access Journals (Sweden)

    Alexander POPE

    2012-11-01

    Full Text Available Despite widespread focus on literacy and math at the expense of other subjects, citizenship and environmental education have an important role in American public education. Citizenship and environmental education are broadly tasked with helping students develop the knowledge, skills, and attitudes needed to shepherd the body politic and natural world, respectively, into the future. For educators and administrators concerned with instructional efficiency, educational farm visits offer one means of pairing these two approaches into a unified learning experience. This paper presents findings from a qualitative case study analysis of two such programs, incorporating interviews with and observations of visiting students, teachers, and parents. The authors argue that sustainable citizenship—a typically European conception of citizenship that stresses the natural as well as the national world—is an important outcome of these types of educational experiences.

  16. Two Sides of the Megalopolis: Educating for Sustainable Citizenship

    OpenAIRE

    Alexander POPE; Timothy PATTERSON

    2012-01-01

    Despite widespread focus on literacy and math at the expense of other subjects, citizenship and environmental education have an important role in American public education. Citizenship and environmental education are broadly tasked with helping students develop the knowledge, skills, and attitudes needed to shepherd the body politic and natural world, respectively, into the future. For educators and administrators concerned with instructional efficiency, educational farm visits offer one mean...

  17. Reputation and Reward: Two Sides of the Same Bitcoin

    Science.gov (United States)

    Delgado-Segura, Sergi; Tanas, Cristian; Herrera-Joancomartí, Jordi

    2016-01-01

    In Mobile Crowd Sensing (MCS), the power of the crowd, jointly with the sensing capabilities of the smartphones they wear, provides a new paradigm for data sensing. Scenarios involving user behavior or those that rely on user mobility are examples where standard sensor networks may not be suitable, and MCS provides an interesting solution. However, including human participation in sensing tasks presents numerous and unique research challenges. In this paper, we analyze three of the most important: user participation, data sensing quality and user anonymity. We tackle the three as a whole, since all of them are strongly correlated. As a result, we present PaySense, a general framework that incentivizes user participation and provides a mechanism to validate the quality of collected data based on the users’ reputation. All such features are performed in a privacy-preserving way by using the Bitcoin cryptocurrency. Rather than a theoretical one, our framework has been implemented, and it is ready to be deployed and complement any existing MCS system. PMID:27240373

  18. Supervised versus unsupervised categorization: two sides of the same coin?

    Science.gov (United States)

    Pothos, Emmanuel M; Edwards, Darren J; Perlman, Amotz

    2011-09-01

    Supervised and unsupervised categorization have been studied in separate research traditions. A handful of studies have attempted to explore a possible convergence between the two. The present research builds on these studies, by comparing the unsupervised categorization results of Pothos et al. ( 2011 ; Pothos et al., 2008 ) with the results from two procedures of supervised categorization. In two experiments, we tested 375 participants with nine different stimulus sets and examined the relation between ease of learning of a classification, memory for a classification, and spontaneous preference for a classification. After taking into account the role of the number of category labels (clusters) in supervised learning, we found the three variables to be closely associated with each other. Our results provide encouragement for researchers seeking unified theoretical explanations for supervised and unsupervised categorization, but raise a range of challenging theoretical questions.

  19. Reputation and Reward: Two Sides of the Same Bitcoin.

    Science.gov (United States)

    Delgado-Segura, Sergi; Tanas, Cristian; Herrera-Joancomartí, Jordi

    2016-05-27

    In Mobile Crowd Sensing (MCS), the power of the crowd, jointly with the sensing capabilities of the smartphones they wear, provides a new paradigm for data sensing. Scenarios involving user behavior or those that rely on user mobility are examples where standard sensor networks may not be suitable, and MCS provides an interesting solution. However, including human participation in sensing tasks presents numerous and unique research challenges. In this paper, we analyze three of the most important: user participation, data sensing quality and user anonymity. We tackle the three as a whole, since all of them are strongly correlated. As a result, we present PaySense, a general framework that incentivizes user participation and provides a mechanism to validate the quality of collected data based on the users' reputation. All such features are performed in a privacy-preserving way by using the Bitcoin cryptocurrency. Rather than a theoretical one, our framework has been implemented, and it is ready to be deployed and complement any existing MCS system.

  20. Reputation and Reward: Two Sides of the Same Bitcoin

    Directory of Open Access Journals (Sweden)

    Sergi Delgado-Segura

    2016-05-01

    Full Text Available In Mobile Crowd Sensing (MCS, the power of the crowd, jointly with the sensing capabilities of the smartphones they wear, provides a new paradigm for data sensing. Scenarios involving user behavior or those that rely on user mobility are examples where standard sensor networks may not be suitable, and MCS provides an interesting solution. However, including human participation in sensing tasks presents numerous and unique research challenges. In this paper, we analyze three of the most important: user participation, data sensing quality and user anonymity. We tackle the three as a whole, since all of them are strongly correlated. As a result, we present PaySense, a general framework that incentivizes user participation and provides a mechanism to validate the quality of collected data based on the users’ reputation. All such features are performed in a privacy-preserving way by using the Bitcoin cryptocurrency. Rather than a theoretical one, our framework has been implemented, and it is ready to be deployed and complement any existing MCS system.

  1. Development and environment - two sides of a coin

    International Nuclear Information System (INIS)

    Hohlfeld, W.; Brommann, R.; Seiberl, L.

    Environmental aspects: pollution, internal insecurity, limits to growth, population explosion, comsumption explosion, the Brokdorf example, danger of confrontations, aims of separate development, necessity of a successive development. Fundamental works on the perspective: Doubt as to quantity, search for a new ethos, maintaining life's value, tiger's reef or lion's den. Didactic-methodic aids: School teaching topic 'Our future'; development help cocktail for church communities. (HP) [de

  2. Dematerialization and capital maintenance. Two sides of the sustainability coin

    International Nuclear Information System (INIS)

    Bartelmus, Peter

    2003-01-01

    The reductionist trend of equating sustainable development with sustained economic growth needs to be reversed. New accounts and balances help to operationalize the elusive notion of sustainability: they provide a coherent picture of the interaction between environment and economy. 'Greened' national accounts measure economic sustainability in terms of (produced and natural) capital maintenance; balances of material flows assess ecological sustainability as the dematerialization of production and consumption. Both concepts aim to preserve environmental assets, but differ in scope, strength and evaluation of sustainability. First results for Germany indicate weak sustainability of the economy; strong sustainability is not in sight because of insufficient reduction of material throughput. Attaining sustainability through integrated policies needs the support of share- and stakeholders of sustainable development

  3. Measuring political polarization: Twitter shows the two sides of Venezuela

    Science.gov (United States)

    Morales, A. J.; Borondo, J.; Losada, J. C.; Benito, R. M.

    2015-03-01

    We say that a population is perfectly polarized when divided in two groups of the same size and opposite opinions. In this paper, we propose a methodology to study and measure the emergence of polarization from social interactions. We begin by proposing a model to estimate opinions in which a minority of influential individuals propagate their opinions through a social network. The result of the model is an opinion probability density function. Next, we propose an index to quantify the extent to which the resulting distribution is polarized. Finally, we apply the proposed methodology to a Twitter conversation about the late Venezuelan president, Hugo Chávez, finding a good agreement between our results and offline data. Hence, we show that our methodology can detect different degrees of polarization, depending on the structure of the network.

  4. Skin hydration, microrelief and greasiness of normal skin in Antarctica.

    Science.gov (United States)

    Tsankov, N; Mateev, D; Darlenski, R

    2018-03-01

    The skin is the primary defence of the human body against external factors from physical, chemical, mechanical and biologic origin. Climatic factors together with low temperature and sun radiation affect the skin. The effect of climatic conditions in Antarctica on healthy skin has not been previously addressed. The aim of this study was to evaluate the changes in the skin hydration, greasiness and microrelief due to the extreme climatic environmental factors during the stay of the members of the Bulgarian Antarctic expedition. Fifty-nine Caucasian healthy subjects, 42 men and 17 women with mean age 50.9 years (27-68), were enrolled. The study was performed in five consecutive years from 2011 to 2016 at the Bulgarian Antarctic base camp at Livingston Island. The study protocol consisted of two parts: study A: duration of 15 days with measurement of skin physiology parameters on a daily basis, and study B: five measurements at baseline and at days 14, 30, 45 and 50 upon arrival in Antarctica. We measured three biophysical parameters related to skin physiology at cheek skin by an impedance measuring device. No statistically significant difference between parameters at the different measurement points. There is a variation in skin hydration reaching its lower point at day 11 and then returning to values similar to baseline. Initially, an increase in skin greasiness was witnessed with a sharp depression at day 11 and final values at day 15 resembling the ones at baseline. An increase, although not statistically significant, in skin roughness was observed in the first 15 days of the study. Study B showed no statistically significant variances between values of the three parameters. Our studies show the pioneer results of the effect of Antarctic climate on human skin physiology. © 2017 European Academy of Dermatology and Venereology.

  5. Fractional laser skin resurfacing.

    Science.gov (United States)

    Alexiades-Armenakas, Macrene R; Dover, Jeffrey S; Arndt, Kenneth A

    2012-11-01

    Laser skin resurfacing (LSR) has evolved over the past 2 decades from traditional ablative to fractional nonablative and fractional ablative resurfacing. Traditional ablative LSR was highly effective in reducing rhytides, photoaging, and acne scarring but was associated with significant side effects and complications. In contrast, nonablative LSR was very safe but failed to deliver consistent clinical improvement. Fractional LSR has achieved the middle ground; it combined the efficacy of traditional LSR with the safety of nonablative modalities. The first fractional laser was a nonablative erbium-doped yttrium aluminum garnet (Er:YAG) laser that produced microscopic columns of thermal injury in the epidermis and upper dermis. Heralding an entirely new concept of laser energy delivery, it delivered the laser beam in microarrays. It resulted in microscopic columns of treated tissue and intervening areas of untreated skin, which yielded rapid reepithelialization. Fractional delivery was quickly applied to ablative wavelengths such as carbon dioxide, Er:YAG, and yttrium scandium gallium garnet (2,790 nm), providing more significant clinical outcomes. Adjustable laser parameters, including power, pitch, dwell time, and spot density, allowed for precise determination of percent surface area, affected penetration depth, and clinical recovery time and efficacy. Fractional LSR has been a significant advance to the laser field, striking the balance between safety and efficacy.

  6. Gas separation membranes

    Science.gov (United States)

    Schell, William J.

    1979-01-01

    A dry, fabric supported, polymeric gas separation membrane, such as cellulose acetate, is prepared by casting a solution of the polymer onto a shrinkable fabric preferably formed of synthetic polymers such as polyester or polyamide filaments before washing, stretching or calendering (so called griege goods). The supported membrane is then subjected to gelling, annealing, and drying by solvent exchange. During the processing steps, both the fabric support and the membrane shrink a preselected, controlled amount which prevents curling, wrinkling or cracking of the membrane in flat form or when spirally wound into a gas separation element.

  7. Anion exchange membrane

    Science.gov (United States)

    Verkade, John G; Wadhwa, Kuldeep; Kong, Xueqian; Schmidt-Rohr, Klaus

    2013-05-07

    An anion exchange membrane and fuel cell incorporating the anion exchange membrane are detailed in which proazaphosphatrane and azaphosphatrane cations are covalently bonded to a sulfonated fluoropolymer support along with anionic counterions. A positive charge is dispersed in the aforementioned cations which are buried in the support to reduce the cation-anion interactions and increase the mobility of hydroxide ions, for example, across the membrane. The anion exchange membrane has the ability to operate at high temperatures and in highly alkaline environments with high conductivity and low resistance.

  8. Photoresponsive nanostructured membranes

    KAUST Repository

    Madhavan, Poornima

    2016-07-26

    The perspective of adding stimuli-response to isoporous membranes stimulates the development of separation devices with pores, which would open or close under control of environment chemical composition, temperature or exposure to light. Changes in pH and temperature have been previously investigated. In this work, we demonstrate for the first time the preparation of photoresponsive isoporous membranes, applying self-assembly non-solvent induced phase separation to a new light responsive block copolymer. First, we optimized the membrane formation by using poly(styrene-b-anthracene methyl methacrylate-b-methylmethacrylate) (PS-b-PAnMMA-b-PMMA) copolymer, identifying the most suitable solvent, copolymer block length, and other parameters. The obtained final triblock copolymer membrane morphologies were characterized using atomic force and electron microscopy. The microscopic analysis reveals that the PS-b-PAnMMA-b-PMMA copolymer can form both lamellar and ordered hexagonal nanoporous structures on the membrane top layer in appropriate solvent compositions. The nanostructured membrane emits fluorescence due to the presence of the anthracene mid-block. On irradiation of light the PS-b-PAnMMA-b-PMMA copolymer membranes has an additional stimuli response. The anthracene group undergoes conformational changes by forming [4 + 4] cycloadducts and this alters the membrane\\'s water flux and solute retention. © 2016 The Royal Society of Chemistry.

  9. Infrared sensing based sensitive skin

    Institute of Scientific and Technical Information of China (English)

    CAO Zheng-cai; FU Yi-li; WANG Shu-guo; JIN Bao

    2006-01-01

    Developed robotics sensitive skin is a modularized, flexible, mini-type array of infrared sensors with data processing capabilities, which can be used to cover the body of a robot. Depending on the infrared sensors and periphery processing circuit, robotics sensitive skin can in real-time provide existence and distance information about obstacles for robots within sensory areas. The methodology of designing sensitive skin and the algorithm of a mass of IR data fusion are presented. The experimental results show that the multi-joint robot with this sensitive skin can work autonomously in an unknown environment.

  10. Menstrual cycle and skin reactivity

    DEFF Research Database (Denmark)

    Agner, T; Damm, P; Skouby, S O

    1991-01-01

    The hypothesis was tested that a cyclic variation exists in skin reactivity to irritant stimuli. Twenty-nine healthy women with regular menstrual cycles were challenged with sodium lauryl sulfate as an irritant patch test at day 1 and at days 9 through 11 of the menstrual cycle. The skin response...... to the applied irritant stimulus was evaluated by visual scoring and also quantified by measurements of transepidermal water loss, edema formation, and blood flow in the skin. The skin response to challenge with sodium lauryl sulfate was found to be significantly stronger at day 1 than at days 9 through 11...

  11. Skin decontamination: principles and perspectives.

    Science.gov (United States)

    Chan, Heidi P; Zhai, Hongbo; Hui, Xiaoying; Maibach, Howard I

    2013-11-01

    Skin decontamination is the primary intervention needed in chemical, biological and radiological exposures, involving immediate removal of the contaminant from the skin performed in the most efficient way. The most readily available decontamination system on a practical basis is washing with soap and water or water only. Timely use of flushing with copious amounts of water may physically remove the contaminant. However, this traditional method may not be completely effective, and contaminants left on the skin after traditional washing procedures can have toxic consequences. This article focuses on the principles and practices of skin decontamination.

  12. Thin-film composite crosslinked polythiosemicarbazide membranes for organic solvent nanofiltration (OSN)

    KAUST Repository

    Aburabie, Jamaliah

    2015-01-01

    In this work we report a new class of solvent stable thin-film composite (TFC) membrane fabricated on crosslinked polythiosemicarbazide (PTSC) as substrate that exhibits superior stability compared with other solvent stable polymeric membranes reported up to now. Integrally skinned asymmetric PTSC membranes were prepared by the phase inversion process and crosslinked with an aromatic bifunctional crosslinker to improve the solvent stability. TFC membranes were obtained via interfacial polymerization using trimesoyl chloride (TMC) and diaminopiperazine (DAP) monomers. The membranes were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and contact angle measurement.The membranes exhibited high fluxes toward solvents like tetrahydrofuran (THF), dimethylformamide (DMF) and dimethylsulfoxide (DMSO) ranging around 20L/m2 h at 5bar with a molecular weight cut off (MWCO) of around 1000g/mol. The PTSC-based thin-film composite membranes are very stable toward polar aprotic solvents and they have potential applications in the petrochemical and pharmaceutical industry.

  13. Fabrication and Characterization of Polymeric Hollow Fiber Membranes with Nano-scale Pore Sizes

    International Nuclear Information System (INIS)

    Amir Mansourizadeh; Ahmad Fauzi Ismail

    2011-01-01

    Porous polyvinylidene fluoride (PVDF) and polysulfide (PSF) hollow fiber membranes were fabricated via a wet spinning method. The membranes were characterized in terms of gas permeability, wetting pressure, overall porosity and water contact angle. The morphology of the membranes was examined by FESEM. From gas permeation test, mean pore sizes of 7.3 and 9.6 nm were obtained for PSF and PVDF membrane, respectively. Using low polymer concentration in the dopes, the membranes demonstrated a relatively high overall porosity of 77 %. From FESEM examination, the PSF membrane presented a denser outer skin layer, which resulted in significantly lower N 2 permeance. Therefore, due to the high hydrophobicity and nano-scale pore sizes of the PVDF membrane, a good wetting pressure of 4.5x10 -5 Pa was achieved. (author)

  14. A review on polymeric hydrogel membranes for wound dressing applications: PVA-based hydrogel dressings

    Directory of Open Access Journals (Sweden)

    Elbadawy A. Kamoun

    2017-05-01

    Full Text Available This review presents the past and current efforts with a brief description on the featured properties of hydrogel membranes fabricated from biopolymers and synthetic ones for wound dressing applications. Many endeavors have been exerted during past ten years for developing new artificial polymeric membranes, which fulfill the demanded conditions for the treatment of skin wounds. This review mainly focuses on representing specifications of ideal polymeric wound dressing membranes, such as crosslinked hydrogels compatible with wound dressing purposes. But as the hydrogels with single component have low mechanical strength, recent trends have offered composite or hybrid hydrogel membranes to achieve the typical wound dressing requirements.

  15. Composite Membrane Formation by Combination of Reaction-Induced and Nonsolvent-Induced Phase Separation

    KAUST Repository

    Aburabie, Jamaliah; Villalobos, Luis Francisco; Peinemann, Klaus-Viktor

    2017-01-01

    A novel method of preparing skinned asymmetric membranes with two distinctive layers is described: a top layer composed of chemically cross-linked polymer chains (dense layer) and a bottom layer of non-cross-linked polymer chains (porous substructure). The method consists of two simple steps that are compatible with industrial membrane fabrication facilities. Unlike conventional processes to prepare asymmetric membranes, with this approach it is possible to finely control the structure and functionalities of the final membrane. The thickness of the dense layer can be easily controlled over several orders of magnitude and targeted functional groups can be readily incorporated in it.

  16. Composite Membrane Formation by Combination of Reaction-Induced and Nonsolvent-Induced Phase Separation

    KAUST Repository

    Aburabie, Jamaliah

    2017-05-25

    A novel method of preparing skinned asymmetric membranes with two distinctive layers is described: a top layer composed of chemically cross-linked polymer chains (dense layer) and a bottom layer of non-cross-linked polymer chains (porous substructure). The method consists of two simple steps that are compatible with industrial membrane fabrication facilities. Unlike conventional processes to prepare asymmetric membranes, with this approach it is possible to finely control the structure and functionalities of the final membrane. The thickness of the dense layer can be easily controlled over several orders of magnitude and targeted functional groups can be readily incorporated in it.

  17. Use of Clotted Human Plasma and Aprotinin in Skin Tissue Engineering: A Novel Approach to Engineering Composite Skin on a Porous Scaffold.

    Science.gov (United States)

    Paul, Michelle; Kaur, Pritinder; Herson, Marisa; Cheshire, Perdita; Cleland, Heather; Akbarzadeh, Shiva

    2015-10-01

    Tissue-engineered composite skin is a promising therapy for the treatment of chronic and acute wounds, including burns. Providing the wound bed with a dermal scaffold populated by autologous dermal and epidermal cellular components can further entice host cell infiltration and vascularization to achieve permanent wound closure in a single stage. However, the high porosity and the lack of a supportive basement membrane in most commercially available dermal scaffolds hinders organized keratinocyte proliferation and stratification in vitro and may delay re-epithelization in vivo. The objective of this study was to develop a method to enable the in vitro production of a human skin equivalent (HSE) that included a porous scaffold and dermal and epidermal cells expanded ex vivo, with the potential to be used for definitive treatment of skin defects in a single procedure. A collagen-glycosaminoglycan dermal scaffold (Integra(®)) was populated with adult fibroblasts. A near-normal skin architecture was achieved by the addition of coagulated human plasma to the fibroblast-populated scaffold before seeding cultured keratinocytes. This resulted in reducing scaffold pore size and improving contact surfaces. Skin architecture and basement membrane formation was further improved by the addition of aprotinin (a serine protease inhibitor) to the culture media to inhibit premature clot digestion. Histological assessment of the novel HSE revealed expression of keratin 14 and keratin 10 similar to native skin, with a multilayered neoepidermis morphologically comparable to human skin. Furthermore, deposition of collagen IV and laminin-511 were detected by immunofluorescence, indicating the formation of a continuous basement membrane at the dermal-epidermal junction. The proposed method was efficient in producing an in vitro near native HSE using the chosen off-the-shelf porous scaffold (Integra). The same principles and promising outcomes should be applicable to other biodegradable

  18. HLA-DPDQDR is expressed in all lesional skin from patients with autoimmune skin diseases

    Directory of Open Access Journals (Sweden)

    Ana Maria Abreu Velez

    2014-04-01

    Full Text Available Introduction: Human genes responsible for human antigen presentation and transplant rejection functions are located on the short arm of Chromosome 6 and are called the Major Histocompatibility Complex (MHC. Moreover, the primary physiologic function of MHC molecules is to present peptides to T lymphocytes. MHC molecules are integral components of the ligands that most T cells recognize, since the T cell receptor (TCR has specificity for complexes of foreign antigenic peptides, as well as self-MHC molecules. Aim: Our investigation attempts to investigate the presence of HLA-DPDQDR within lesional skin biopsies from patients affected by autoimmune skin blistering diseases (ABDs. Materials and Methods: We utilized immunohistochemistry (IHC to evaluate the presence of HLA-DPDQDR in lesional skin biopsies of patients affected by ABDs. We tested 30 patients with endemic pemphigus foliaceus (EPF, 15 controls from the EPF endemic area, and 15 biopsies from healthy controls from the USA. We also tested archival biopsies from patients with selected ABDs, including 30 patients with bullous pemphigoid (BP, 20 with pemphigus vulgaris (PV, 8 with pemphigus foliaceus (PF, 14 with dermatitis herpetiformis (DH and 2 with epidermolysis bullosa acquisita (EBA. Results: Most ABD biopsies stained positive for HLA-DPDQDR in the lesional blisters and/or inflamed neurovascular plexus in the superficial dermis, and also at mesenchymal-endothelial like-cell junctions in the dermis. In BP, EBA and EPF, the HLA-DPDQDR staining was also seen in the dermal eccrine sweat gland coils and and ducts. Conclusion: Here, we document that HLA-DPDQDR is expressed in several anatomic areas of lesional skin in patients with ABDs. Notably, HLA-DPDQDR positivity was also consistently present in areas of the classic immune response in pemphigus epidermal keratinocytic intercellular junctions, and at basement membrane sites in bullous pemphigoid and other subepidermal blistering diseases.

  19. Membrane fusion and exocytosis.

    Science.gov (United States)

    Jahn, R; Südhof, T C

    1999-01-01

    Membrane fusion involves the merger of two phospholipid bilayers in an aqueous environment. In artificial lipid bilayers, fusion proceeds by means of defined transition states, including hourglass-shaped intermediates in which the proximal leaflets of the fusing membranes are merged whereas the distal leaflets are separate (fusion stalk), followed by the reversible opening of small aqueous fusion pores. Fusion of biological membranes requires the action of specific fusion proteins. Best understood are the viral fusion proteins that are responsible for merging the viral with the host cell membrane during infection. These proteins undergo spontaneous and dramatic conformational changes upon activation. In the case of the paradigmatic fusion proteins of the influenza virus and of the human immunodeficiency virus, an amphiphilic fusion peptide is inserted into the target membrane. The protein then reorients itself, thus forcing the fusing membranes together and inducing lipid mixing. Fusion of intracellular membranes in eukaryotic cells involves several protein families including SNAREs, Rab proteins, and Sec1/Munc-18 related proteins (SM-proteins). SNAREs form a novel superfamily of small and mostly membrane-anchored proteins that share a common motif of about 60 amino acids (SNARE motif). SNAREs reversibly assemble into tightly packed helical bundles, the core complexes. Assembly is thought to pull the fusing membranes closely together, thus inducing fusion. SM-proteins comprise a family of soluble proteins that bind to certain types of SNAREs and prevent the formation of core complexes. Rab proteins are GTPases that undergo highly regulated GTP-GDP cycles. In their GTP form, they interact with specific proteins, the effector proteins. Recent evidence suggests that Rab proteins function in the initial membrane contact connecting the fusing membranes but are not involved in the fusion reaction itself.

  20. Non-ablative skin tightening with radiofrequency in Asian skin.

    Science.gov (United States)

    Kushikata, Nobuharu; Negishi, Kei; Tezuka, Yukiko; Takeuchi, Kaori; Wakamatsu, Shingo

    2005-02-01

    The recent successful application of radiofrequency (RF) in non-ablative skin tightening for skin laxity has attracted attention worldwide. The efficacy and clinical effect of RF were assessed in Asian skin, with additional study on the duration of the effect and any complications. Eighty-five Japanese females were enrolled in the study for treatment of nasolabial folds, marionette lines, and sagging jowls with 6-month follow-up. RF treatment was effective for nasolabial folds, marionette lines, and jowls. Objective physician evaluation found relatively good improvement at 3 months post-treatment, and even better improvement at the 6-month evaluation. RF treatment was very satisfactory for skin tightening in Asian facial skin. When compared with published literature from the United States, the results suggested that there might be race-related differences in the treatment parameters. (c) 2005 Wiley-Liss, Inc.

  1. Autoimmune Subepidermal Bullous Diseases of the Skin and Mucosae: Clinical Features, Diagnosis, and Management.

    Science.gov (United States)

    Amber, Kyle T; Murrell, Dedee F; Schmidt, Enno; Joly, Pascal; Borradori, Luca

    2018-02-01

    Autoimmune subepidermal blistering diseases of the skin and mucosae constitute a large group of sometimes devastating diseases, encompassing bullous pemphigoid, gestational pemphigoid, mucous membrane pemphigoid, epidermolysis bullosa acquisita, and anti-p200 pemphigoid. Their clinical presentation is polymorphic. These autoimmune blistering diseases are associated with autoantibodies that target distinct components of the basement membrane zone of stratified epithelia. These autoantigens represent structural proteins important for maintenance of dermo-epidermal integrity. Bullous pemphigoid (BP) is the most common subepidermal autoimmune blistering disease of the skin and mucosae. Although the disease typically presents with a generalized blistering eruption associated with itch, atypical variants with either localized bullous lesions or "non-bullous" presentations are observed in approximately 20% of patients. A peculiar form of BP typically associated with pregnancy is pemphigoid gestationis. In anti-p200 pemphigoid, patients present with tense blisters on erythematosus or normal skin resembling BP, with a predilection for acral surfaces. These patients have antibodies targeting the 200-kDa basement membrane protein. Epidermolysis bullosa is a rare autoimmune blistering disease associated with autoantibodies against type VII collagen that can have several phenotypes including a classical form mimicking dystrophic epidermolysis bullosa, an inflammatory presentation mimicking BP, or mucous membrane pemphigoid-like lesions. Mucous membrane pemphigoid (MMP) is the term agreed upon by international consensus for an autoimmune blistering disorder, which affects one or more mucous membrane and may involve the skin. The condition involves a number of different autoantigens in the basement membrane zone. It may result in severe complications from scarring, such as blindness and strictures. Diagnosis of these diseases relies on direct immunofluorescence microscopy studies

  2. Plasma membrane ATPases

    DEFF Research Database (Denmark)

    Palmgren, Michael Broberg; Bækgaard, Lone; Lopez Marques, Rosa Laura

    2011-01-01

    The plasma membrane separates the cellular contents from the surrounding environment. Nutrients must enter through the plasma membrane in order to reach the cell interior, and toxic metabolites and several ions leave the cell by traveling across the same barrier. Biological pumps in the plasma me...

  3. Polymide gas separation membranes

    Science.gov (United States)

    Ding, Yong; Bikson, Benjamin; Nelson, Joyce Katz

    2004-09-14

    Soluble polyamic acid salt (PAAS) precursors comprised of tertiary and quaternary amines, ammonium cations, sulfonium cations, or phosphonium cations, are prepared and fabricated into membranes that are subsequently imidized and converted into rigid-rod polyimide articles, such as membranes with desirable gas separation properties. A method of enhancing solubility of PAAS polymers in alcohols is also disclosed.

  4. Enantioseparation with liquid membranes

    NARCIS (Netherlands)

    Gössi, Angelo; Riedl, Wolfgang; Schuur, Boelo

    Chiral resolution of racemic products is a challenging and important task in the pharmaceutical, agrochemical, flavor, polymer and fragrances industries. One of the options for these challenging separations is to use liquid membranes. Although liquid membranes have been known for almost four decades

  5. Silicon nitride nanosieve membrane

    NARCIS (Netherlands)

    Tong, D.H.; Jansen, Henricus V.; Gadgil, V.J.; Bostan, C.G.; Berenschot, Johan W.; van Rijn, C.J.M.; Elwenspoek, Michael Curt

    2004-01-01

    An array of very uniform cylindrical nanopores with a pore diameter as small as 25 nm has been fabricated in an ultrathin micromachined silicon nitride membrane using focused ion beam (FIB) etching. The pore size of this nanosieve membrane was further reduced to below 10 nm by coating it with

  6. Membrane capacitive deionization

    NARCIS (Netherlands)

    Biesheuvel, P.M.; Wal, van der A.

    2010-01-01

    Membrane capacitive deionization (MCDI) is an ion-removal process based on applying an electrical potential difference across an aqueous solution which flows in between oppositely placed porous electrodes, in front of which ion-exchange membranes are positioned. Due to the applied potential, ions

  7. Photoresponsive nanostructured membranes

    KAUST Repository

    Madhavan, Poornima; Sutisna, Burhannudin; Sougrat, Rachid; Nunes, Suzana Pereira

    2016-01-01

    The perspective of adding stimuli-response to isoporous membranes stimulates the development of separation devices with pores, which would open or close under control of environment chemical composition, temperature or exposure to light. Changes in pH and temperature have been previously investigated. In this work, we demonstrate for the first time the preparation of photoresponsive isoporous membranes, applying self-assembly non-solvent induced phase separation to a new light responsive block copolymer. First, we optimized the membrane formation by using poly(styrene-b-anthracene methyl methacrylate-b-methylmethacrylate) (PS-b-PAnMMA-b-PMMA) copolymer, identifying the most suitable solvent, copolymer block length, and other parameters. The obtained final triblock copolymer membrane morphologies were characterized using atomic force and electron microscopy. The microscopic analysis reveals that the PS-b-PAnMMA-b-PMMA copolymer can form both lamellar and ordered hexagonal nanoporous structures on the membrane top layer in appropriate solvent compositions. The nanostructured membrane emits fluorescence due to the presence of the anthracene mid-block. On irradiation of light the PS-b-PAnMMA-b-PMMA copolymer membranes has an additional stimuli response. The anthracene group undergoes conformational changes by forming [4 + 4] cycloadducts and this alters the membrane's water flux and solute retention. © 2016 The Royal Society of Chemistry.

  8. Double-Skin Facade

    DEFF Research Database (Denmark)

    Kalyanova, Olena

    favored by companies and their employees. To bring the reduction of energy use in these buildings application of suitable tools and methods is necessary to achieve successful design solutions. Earlier work on the topic of DSF modelling was examined from various publications. As a result, the main...... IEA Annex 34/43, subtask E "Double-Skin Facade". The results of empirical validation are discussed in this work. Discussion and analysis of experimental results is carried out. It has lead to hypothesis of recirculation flow phenomenon in the DSF cavity. Finally, a suggestion of a new numerical model...... is developed to account for recirculation flow appearance in the DSF cavity. The model is based on a simple mass balance between the boundary layer flow and the main flow in the cavity....

  9. Regulatory T cells in skin.

    Science.gov (United States)

    Ali, Niwa; Rosenblum, Michael D

    2017-11-01

    Foxp3 + CD4 + regulatory T (Treg) cells are a subset of immune cells that function to regulate tissue inflammation. Skin is one of the largest organs and is home to a large proportion of the body's Treg cells. However, relative to other tissues (such as the spleen and gastrointestinal tract) the function of Treg cells in skin is less well defined. Here, we review our understanding of how Treg cells migrate to skin and the cellular and molecular pathways required for their maintenance in this tissue. In addition, we outline what is known about the specialized functions of Treg cells in skin. Namely, the orchestration of stem cell-mediated hair follicle regeneration, augmentation of wound healing, and promoting adaptive immune tolerance to skin commensal microbes. A comprehensive understanding of the biology of skin Treg cells may lead to novel therapeutic approaches that preferentially target these cells to treat cutaneous autoimmunity, skin cancers and disorders of skin regeneration. © 2017 John Wiley & Sons Ltd.

  10. Skin quality in red potatoes

    Science.gov (United States)

    Attractive appearance is a highly desirable characteristic of fresh market red-skinned potatoes. The ideal red potato has a rich, uniform, deep red color. Color fading, netting, browning, and discoloration caused by skinning and disease decrease marketability and may reduce profits to growers and pa...

  11. Radiation Therapy for Skin Cancer

    Science.gov (United States)

    ... complete chart of side effects. Side effects of Skin Cancer Treatment OrganSystem General Body • cTo ( i D rme ... scrilineesnr/ desbuaoocrnfettedhh) e( ersatkrrieena) tment HELPFUL WEBSITES ON SKIN CANCER TARG E T I NG C A NC ...

  12. Molecular Interactions at Membranes

    DEFF Research Database (Denmark)

    Jagalski, Vivien

    . Today, we know more than ever before about the properties of biological membranes. Advanced biophysical techniques and sophisticated membrane models allow us to answer specific questions about the structure of the components within membranes and their interactions. However, many detailed structural...... the surface-immobilization of LeuT by exchanging the detergent with natural phosphatidylcholine (PC) lipids. Various surface sensitive techniques, including neutron reflectometry (NR), are employed and finally enabled us to confirm the gross structure of LeuT in a lipid environment as predicted by molecular...... dynamic simulations. In a second study, the co-localization of three toxic plant-derived diterpene resin acids (RAs) within DPPC membranes was investigated. These compounds are reported to disrupt the membrane and increase its fluidity. The RAs used in this study vary in their toxicity while...

  13. Membrane technology and applications

    International Nuclear Information System (INIS)

    Khalil, F.H.

    1997-01-01

    The main purpose of this dissertation is to prepare and characterize some synthetic membranes obtained by radiation-induced graft copolymerization of and A Am unitary and binary system onto nylon-6 films. The optimum conditions at which the grafting process proceeded homogeneously were determined. Some selected properties of the prepared membranes were studied. Differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), x-ray diffraction (XRD), mechanical properties and U.V./vis, instruments and techniques were used to characterize the prepared membranes. The use of such membranes for the decontamination of radioactive waste and some heavy metal ions as water pollutants were investigated. These grafted membranes showed good cation exchange properties and may be of practical interest in waste water treatment whether this water was radioactive or not. 4 tabs., 68 figs., 146 refs

  14. 媒体产业中的平台质量竞争——基于双边市场的理论视角的研究%Research on Platform Quality Competition in the Media Industry Based on Two-sided Market Theory

    Institute of Scientific and Technical Information of China (English)

    万兴

    2012-01-01

    The media industry is a typical two-sided market, where audiences and advertisers are the two sides. There are two typieal faets of the two-sided markets in the media industry. Firstly, the major revenue source of the same category media platform may differ. The feature is rare in other industries, where the make-money side is fixed. Secondly, the first-mover advantage in the media industry is not as remarkable as in other industries that are characterized by network effect. The first-mover advantage often brings entry barriers for a later comer, but the media industry witnesses many eases of successful market entry. How to analyze the difference in major revenue source, the traditional horizontal difference model or one-sided model cannot give reasonable explanation. The qual- ity difference of media contents is critical for a media platform to choose its business model. The paper establishes a two-sided market model including the quality factor to analyze the monopoly and duopoly situation. The paper has two contributions. Firstly, this paper incorporates quality into a two-sided model to analyze the quality choice of a platform on market performance. Secondly, this paper uses the quality-difference model to analyze whether or not there is the first-mover advantage in a two-sided media market and whether or not a latecomer can gain advantage over an incumbent. This paper establishes the two-sided model and makes discussion using the TV channel industry as an example. However, the modeling process and results are not limited to the industry but suitable for many media sectors. The research finds that a monopoly platform can make profits from the audience side with high content quality or depends on advertisement fees based on network externalities, but a strategy of tradeoff is not desirable. With the increase of network externalities between audiences and advertisers, the audience-side and advertiser-side profits both inerease. With the increase of eontent

  15. SMART SKINS - A Development Roadmap

    Science.gov (United States)

    Lochocki, Joseph M.

    1990-02-01

    The Air Force Project Forecast II identified a number of key technology initiatives for development. This paper addresses one such initiative, PT-16, Smart Skins. The concept of the Smart Skin is introduced by briefly highlighting its attributes and potential advantages over standard avionics packaging and maintenance, and then goes on to describe some of the key ingredients necessary for its development. Problem areas are brought out along with some of the required trades that must be made. Finally, a time phased development roadmap is introduced which shows Calspan's proposed sequence of technology development programs that can, in combination, lead to first functional Smart Skins implementations in narrowband form in the late 1990's and in wideband form in first decade of the twenty - first century. A Smart Skins implementation in integral aircraft skin structure form will take at least until 2010.

  16. Effect of Preparation Methods on Crystallization Behavior and Tensile Strength of Poly(vinylidene fluoride) Membranes.

    Science.gov (United States)

    Liu, Jie; Lu, Xiaolong; Wu, Chunrui

    2013-11-21

    Poly(vinylidene fluoride) (PVDF) membranes were prepared by non solvent induced phase separation (NIPS), melt spinning and the solution-cast method. The effect of preparation methods with different membrane formation mechanisms on crystallization behavior and tensile strength of PVDF membranes was investigated. Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) and X-ray diffraction (XRD) were employed to examine the crystal form of the surface layers and the overall membranes, respectively. Spherulite morphologies and thermal behavior of the membranes were studied by polarized light optical microscopy (PLO) and differential scanning calorimetry (DSC) separately. It was found that the crystallization behavior of PVDF membranes was closely related to the preparation methods. For membranes prepared by the NIPS method, the skin layers had a mixture of α and β phases, the overall membranes were predominantly α phase, and the total crystallinity was 60.0% with no spherulite. For melt spinning membranes, the surface layers also showed a mixture of α and β phases, the overall membranes were predominantly α phase. The total crystallinity was 48.7% with perfect spherulites. Whereas the crystallization behavior of solution-cast membranes was related to the evaporation temperature and the additive, when the evaporation temperature was 140 °C with a soluble additive in the dope solution, obvious spherulites appeared. The crystalline morphology of PVDF exerted a great influence on the tensile strength of the membranes, which was much higher with perfect spherulites.

  17. Karakteristik Membran Asimetris Polietersufone (PES dengan Pelarut Dimetil Formamide dan N-Metil-2-Pyrolidone - (Characteristic of Poliethersulfone (PES Asymmetric Membrane with Dimethyl Formamide and N-Methyl Pyrolidone as Solvent

    Directory of Open Access Journals (Sweden)

    Sri Mulyati

    2017-06-01

    Full Text Available Membrane that is generally used for separation process could be made using phase inversion technique. This research aims to create polyethersulfone (PES asymmetric membranes via phase inversion technique using solvent and Trans Membrane Pressure (TMP as variable. SEM analysis indicated that membranes had asymmetric structure that consits of two layers which denser skin layer on the top surface and the porous support on the bottom. PES/DMF membrane showed larger pore structure than PES/NMP. The permeability coefficients of both membranes were in the ultrafiltration range. The coefficient permeability (Lp of PES/DMF membrane was 35.769 L/m2.hour, much greater compared to PES/NMP membrane which was 15.364 L/m2.hour.bar. Molecular Weight Cut-Off (MWCO of PES/DMF membrane was 177 Kda, meanwhile PES/NMP was 186 Kda. Performances of the membranes were evaluated  using dextrane as feed solution. PES/DMF membrane resulted in an higher flux and lower rejection than PES/NMP.Keywords: asymmetric membrane, membrane performance, Molecular Weight Cut-Off (MWCO, morphology, permeability ABSTRAKMembran yang umumnya digunakan untuk proses pemisahan dapat dibuat menggunakan teknik inversi fasa. Penelitian ini bertujuan untuk mengetahui karakteristik membran asimetris polietersulfone (PES yang dibuat menggunakan teknik inversi fasa dengan variabel jenis pelarut dan Trans Membrane Pressure (TMP. Hasil analisis Scanning Electron Microscopy (SEM terhadap morfologi membran membuktikan bahwa membran yang dihasilkan merupakan membran asimetris yang terdiri dari dua lapisan yaitu bagian atas merupakan lapisan tipis dan lapisan bawah adalah lapisan berpori. Membran PES/DMF memiliki struktur pori yang lebih besar dibandingkan membran PES/NMP. Koefisien permeabilitas kedua membran yang dihasilkan berada dalam jangkauan ultrafiltrasi. Koefisien permeabilitas (Lp membran PES/DMF sebesar 35,769 L/m2.jam, nilai ini jauh lebih besar dibandingkan PES/NMP yaitu 15,364 L/m2.jam

  18. Matching the skin barrier to the skin type.

    Science.gov (United States)

    Thompson, Hyacinth; North, Jacqui; Davenport, Rebecca; Williams, Julia

    Peristomal skin problems are thought to be common (Herlufsson et al, 2006; Williams et al, 2010), and can interfere with the security of stoma products. Stoma patients are reliant on the integrity of their peristomal skin to maintain a normal lifestyle. Bekkers et al (1996) highlighted that, if the peristomal skin becomes damaged, it not only affects the person physically, but also psychologically, ultimately prolonging rehabilitation and adaptation to the stoma. Therefore, it can be concluded that maintaining skin integrity is a basic and essential skill in ensuring good stoma management. This article explores the assessment of four stoma patients, highlighting the importance of matching their skin type with their skin barrier for optimum skin protection. The patients have kindly agreed for their case studies to be published as a means of informing others. All names have been changed in line with Nursing and Midwifery Council (2010) guidelines to maintain patient confidentiality. This article was originally presented at the World Council of Enterostomal Therapists' (WCET) annual conference in 2010, receiving first prize at poster presentations.

  19. Is skin penetration a determining factor in skin sensitization ...

    Science.gov (United States)

    Summary:Background. It is widely accepted that substances that cannot penetrate through the skin will not be sensitisers. Thresholds based on relevant physicochemical parameters such as a LogKow > 1 and a MW 1 is a true requirement for sensitisation.Methods. A large dataset of substances that had been evaluated for their skin sensitisation potential, together with measured LogKow values was compiled from the REACH database. The incidence of skin sensitisers relative to non-skin sensitisers below and above the LogKow = 1 threshold was evaluated. Results. 1482 substances with associated skin sensitisation outcomes and measured LogKow values were identified. 305 substances had a measured LogKow self-evident truth borne out from the widespread misconception that the ability to efficiently penetrate the stratum corneum is a key determinant of skin sensitisation potential and potency. Using the REACH data extracted to test out the validity of common assumptions in the skin sensitization AOP. Builds on trying to develop a proof of concept IATA

  20. Polymeric membranes modulate human keratinocyte differentiation in specific epidermal layers.

    Science.gov (United States)

    Salerno, Simona; Morelli, Sabrina; Giordano, Francesca; Gordano, Amalia; Bartolo, Loredana De

    2016-10-01

    In vitro models of human bioengineered skin substitutes are an alternative to animal experimentation for testing the effects and toxicity of drugs, cosmetics and pollutants. For the first time specific and distinct human epidermal strata were engineered by using membranes and keratinocytes. To this purpose, biodegradable membranes of chitosan (CHT), polycaprolactone (PCL) and a polymeric blend of CHT-PCL were prepared by phase-inversion technique and characterized in order to evaluate their morphological, physico-chemical and mechanical properties. The capability of membranes to modulate keratinocyte differentiation inducing specific interactions in epidermal membrane systems was investigated. The overall results demonstrated that the membrane properties strongly influence the cell morpho-functional behaviour of human keratinocytes, modulating their terminal differentiation, with the creation of specific epidermal strata or a fully proliferative epidermal multilayer system. In particular, human keratinocytes adhered on CHT and CHT-PCL membranes, forming the structure of the epidermal top layers, such as the corneum and granulosum strata, characterized by withdrawal or reduction from the cell cycle and cell proliferation. On the PCL membrane, keratinocytes developed an epidermal basal lamina, with high proliferating cells that stratified and migrated over time to form a complete differentiating epidermal multilayer system. Copyright © 2016 Elsevier B.V. All rights reserved.