Sample records for abnormal macropore formation

  1. Abnormal macropore formation during double-sided gas tungsten arc welding of magnesium AZ91D alloy

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

    Shen Jun; You Guoqiang; Long Siyuan

    2008-08-15

    One of the major concerns during gas tungsten arc (GTA) welding of cast magnesium alloys is the presence of large macroporosity in weldments, normally thought to occur from the presence of gas in the castings. In this study, a double-sided GTA welding process was adopted to join wrought magnesium AZ91D alloy plates. Micropores were formed in the weld zone of the first side that was welded, due to precipitation of H{sub 2} as the mushy zone freezes. When the reverse side was welded, the heat generated caused the mushy zone in the initial weld to reform. The micropores in themore » initial weld then coalesced and expanded to form macropores by means of gas expansion through small holes that are present at the grain boundaries in the partially melted zone. Macropores in the partially melted zone increase with increased heat input, so that when a filler metal is used the macropores are smaller in number and in size.« less

  2. Macroporous ceramics by colloidal templating

    NASA Astrophysics Data System (ADS)

    Subramaniam, G.; Pine, David J.

    2000-04-01

    We describe a novel method of fabricating macroporous ceramics employing colloidal dispersion of ultrafine ceramic particles with latex particles as the templates. The colloidal particles form a particulate gel on drying and fill the voids of the ordered latex templates. Subsequent removal of the template by calcination results in the formation of an ordered macroporous ceramic. The process has significant advantages over the traditional sol-gel process employing alkoxide precursors. Most importantly, the much lower shrinkage compared to the sol-gel process enabled us to produce larger pieces of the sample. The larger shrinkage involved in the sol-gel process often results in small and fragile pieces of the macroporous material which has to be subsequently heat treated to induce crystallization. The ability to choose crystalline colloidal particles in our method obviates the need for heat treatment to achieve crystallinity. We have synthesized a variety of materials such as macroporous silica, titania, alumina and recently have also extended the approach to macroporous silicon which is not amenable to the sol-gel process.

  3. Direct observation of macrostructure formation of hierarchically structured meso-macroporous aluminosilicates with 3D interconnectivity by optical microscope.

    PubMed

    Lemaire, Arnaud; Rooke, Joanna Claire; Chen, Li-Hua; Su, Bao-Lian

    2011-03-15

    Hierarchically structured spongy meso-macroporous aluminosilicates with high tetrahedral aluminum content were synthesized from a mixture of single molecular alkoxide precursor, (sec-BuO)2-Al-O-Si(OEt)3, already containing Si-O-Al bonds, and a silica coreactant, tetramethoxysilane (TMOS). The spontaneous byproduct templated macroporous structure formation has been directly visualized using in situ high-resolution optical microscopy (OM), allowing the crucial observation of a microbubble dispersion which is directly correlated to the macrostructure observed by electronic microscopies (SEM and TEM). This discovery leads to a comparative study with meso-macroporous pure metal oxide and to a proposal of the formation mechanism of meso-macroporous aluminosilicates with 3D interconnectivity. The aluminosilicate phase/microbubbles emulsion is produced by a phase separation process occurring between the aluminosilicate nanoparticles and the liquid hydrolysis-condensation reaction byproducts (water, methanol, ethanol, and butanol). The use of alkoxysilane improves the heterocondensation rates between the highly reactive aluminum alkoxide part of the single precursor and added silica species but, above all, leads to the spontaneous generation of an unusual meso-macroporosity in alkaline media. The particles obtained at pH = 13.0 featured regular micrometer-sized macrospheres separated by very thin mesoporous walls and connected by submicrometric openings, providing a 3D interconnectivity. The slight increase in pH value to 13.5 induced significant modifications in morphology and textural properties due to the slower gelification process of the aluminosilicate phase, resulting in the formation of an aluminosilicate material constituted of 1-2 µm large independent hollow mesoporous spheres.

  4. Calcium ions and osteoclastogenesis initiate the induction of bone formation by coral-derived macroporous constructs

    PubMed Central

    Klar, Roland M; Duarte, Raquel; Dix-Peek, Therese; Dickens, Caroline; Ferretti, Carlo; Ripamonti, Ugo

    2013-01-01

    Coral-derived calcium carbonate/hydroxyapatite macroporous constructs of the genus Goniopora with limited hydrothermal conversion to hydroxyapatite (7% HA/CC) initiate the induction of bone formation. Which are the molecular signals that initiate pattern formation and the induction of bone formation? To evaluate the role of released calcium ions and osteoclastogenesis, 7% HA/CC was pre-loaded with either 500 μg of the calcium channel blocker, verapamil hydrochloride, or 240 μg of the osteoclast inhibitor, biphosphonate zoledronate, and implanted in the rectus abdominis muscle of six adult Chacma baboons Papio ursinus. Generated tissues on days 15, 60 and 90 were analysed by histomorphometry and qRT-PCR. On day 15, up-regulation of type IV collagen characterized all the implanted constructs correlating with vascular invasion. Zoledronate-treated specimens showed an important delay in tissue patterning and morphogenesis with limited bone formation. Osteoclastic inhibition yielded minimal, if any, bone formation by induction. 7% HA/CC pre-loaded with the Ca++ channel blocker verapamil hydrochloride strongly inhibited the induction of bone formation. Down-regulation of bone morphogenetic protein-2 (BMP-2) together with up-regulation of Noggin genes correlated with limited bone formation in 7% HA/CC pre-loaded with either verapamil or zoledronate, indicating that the induction of bone formation by coral-derived macroporous constructs is via the BMPs pathway. The spontaneous induction of bone formation is initiated by a local peak of Ca++ activating stem cell differentiation and the induction of bone formation. PMID:24106923

  5. Parallel fabrication of macroporous scaffolds.

    PubMed

    Dobos, Andrew; Grandhi, Taraka Sai Pavan; Godeshala, Sudhakar; Meldrum, Deirdre R; Rege, Kaushal

    2018-07-01

    Scaffolds generated from naturally occurring and synthetic polymers have been investigated in several applications because of their biocompatibility and tunable chemo-mechanical properties. Existing methods for generation of 3D polymeric scaffolds typically cannot be parallelized, suffer from low throughputs, and do not allow for quick and easy removal of the fragile structures that are formed. Current molds used in hydrogel and scaffold fabrication using solvent casting and porogen leaching are often single-use and do not facilitate 3D scaffold formation in parallel. Here, we describe a simple device and related approaches for the parallel fabrication of macroporous scaffolds. This approach was employed for the generation of macroporous and non-macroporous materials in parallel, in higher throughput and allowed for easy retrieval of these 3D scaffolds once formed. In addition, macroporous scaffolds with interconnected as well as non-interconnected pores were generated, and the versatility of this approach was employed for the generation of 3D scaffolds from diverse materials including an aminoglycoside-derived cationic hydrogel ("Amikagel"), poly(lactic-co-glycolic acid) or PLGA, and collagen. Macroporous scaffolds generated using the device were investigated for plasmid DNA binding and cell loading, indicating the use of this approach for developing materials for different applications in biotechnology. Our results demonstrate that the device-based approach is a simple technology for generating scaffolds in parallel, which can enhance the toolbox of current fabrication techniques. © 2018 Wiley Periodicals, Inc.

  6. Functionalization of 2D macroporous silicon under the high-pressure oxidation

    NASA Astrophysics Data System (ADS)

    Karachevtseva, L.; Kartel, M.; Kladko, V.; Gudymenko, O.; Bo, Wang; Bratus, V.; Lytvynenko, O.; Onyshchenko, V.; Stronska, O.

    2018-03-01

    Addition functionalization after high-pressure oxidation of 2D macroporous silicon structures is evaluated. X-ray diffractometry indicates formation of orthorhombic SiO2 phase on macroporous silicon at oxide thickness of 800-1200 nm due to cylindrical symmetry of macropores and high thermal expansion coefficient of SiO2. Pb center concentration grows with the splitting energy of LO- and TO-phonons and SiO2 thickness in oxidized macroporous silicon structures. This increase EPR signal amplitude and GHz radiation absorption and is promising for development of high-frequency devices and electronically controlled elements.

  7. Macroporous Hydrogel Scaffolds for Three-Dimensional Cell Culture and Tissue Engineering.

    PubMed

    Fan, Changjiang; Wang, Dong-An

    2017-10-01

    Hydrogels have been promising candidate scaffolds for cell delivery and tissue engineering due to their tissue-like physical properties and capability for homogeneous cell loading. However, the encapsulated cells are generally entrapped and constrained in the submicron- or nanosized gel networks, seriously limiting cell growth and tissue formation. Meanwhile, the spatially confined settlement inhibits attachment and spreading of anchorage-dependent cells, leading to their apoptosis. In recent years, macroporous hydrogels have attracted increasing attention in use as cell delivery vehicles and tissue engineering scaffolds. The introduction of macropores within gel scaffolds not only improves their permeability for better nutrient transport but also creates space/interface for cell adhesion, proliferation, and extracellular matrix deposition. Herein, we will first review the development of macroporous gel scaffolds and outline the impact of macropores on cell behaviors. In the first part, the advantages and challenges of hydrogels as three-dimensional (3D) cell culture scaffolds will be described. In the second part, the fabrication of various macroporous hydrogels will be presented. Third, the enhancement of cell activities within macroporous gel scaffolds will be discussed. Finally, several crucial factors that are envisaged to propel the improvement of macroporous gel scaffolds are proposed for 3D cell culture and tissue engineering.

  8. Macroporous Semiconductors

    PubMed Central

    Föll, Helmut; Leisner, Malte; Cojocaru, Ala; Carstensen, Jürgen

    2010-01-01

    Pores in single crystalline semiconductors come in many forms (e.g., pore sizes from 2 nm to > 10 µm; morphologies from perfect pore crystal to fractal) and exhibit many unique properties directly or as nanocompounds if the pores are filled. The various kinds of pores obtained in semiconductors like Ge, Si, III-V, and II-VI compound semiconductors are systematically reviewed, emphasizing macropores. Essentials of pore formation mechanisms will be discussed, focusing on differences and some open questions but in particular on common properties. Possible applications of porous semiconductors, including for example high explosives, high efficiency electrodes for Li ion batteries, drug delivery systems, solar cells, thermoelectric elements and many novel electronic, optical or sensor devices, will be introduced and discussed.

  9. Unique organogel formation with macroporous materials constructed by the freeze-drying of aqueous cyclodextrin solutions.

    PubMed

    Marui, Yasuhiro; Kikuzawa, Akira; Kida, Toshiyuki; Akashi, Mitsuru

    2010-07-06

    Macroporous cyclodextrin materials (MP-alpha-, beta-, and gamma-CDs) were easily fabricated by the freeze-drying of aqueous solutions of alpha-, beta-, and gamma-CDs. These MP-CDs showed the absorption ability toward various organic solvents and oils to give organogels at ambient temperature. The morphological changes of the MP-CD microstructures were observed through the absorption of organic solvents. In particular, the absorption of polar organic solvents with hydrogen-bond forming ability, including 1,4-dioxane and ethanol, by the MP-CDs caused remarkable morphological changes in the microstructures. The absorption of these polar solvents by MP-alpha- and gamma-CDs resulted in the formation of channel-type assemblies of alpha- and gamma-CDs, respectively.

  10. Synthesis of macroporous structures

    DOEpatents

    Stein, Andreas; Holland, Brian T.; Blanford, Christopher F.; Yan, Hongwei

    2004-01-20

    The present application discloses a method of forming an inorganic macroporous material. In some embodiments, the method includes: providing a sample of organic polymer particles having a particle size distribution of no greater than about 10%; forming a colloidal crystal template of the sample of organic polymer particles, the colloidal crystal template including a plurality of organic polymer particles and interstitial spaces therebetween; adding an inorganic precursor composition including a noncolloidal inorganic precursor to the colloidal crystal template such that the precursor composition permeates the interstitial spaces between the organic polymer particles; converting the noncolloidal inorganic precursor to a hardened inorganic framework; and removing the colloidal crystal template from the hardened inorganic framework to form a macroporous material. Inorganic macroporous materials are also disclosed.

  11. Soil Susceptibility to Macropore Flow Across a Desert-Oasis Ecotone of the Hexi Corridor, Northwest China

    NASA Astrophysics Data System (ADS)

    Zhang, Yongyong; Zhao, Wenzhi; He, Jianhua; Fu, Li

    2018-02-01

    Macropore flow not only provides a fast pathway for water and solute transport and increases the risks of water and nutrient loss but also enhances soil aeration and groundwater recharge. However, macropore flow characteristics in irrigated oasis soils subject to continuous crop cultivation are poorly understood. This study was to investigate the effect of continuous cultivation on soil properties and macropore flow and to quantify the changes in macropore flow characteristics in an old oasis field (>50 years of cultivation, OOF), young oasis field (20 years, YOF), and adjacent uncultivated sandy area (0 year, USL) in Northwest China. Triplicate soil samples were collected from each site to investigate soil properties. Dye tracer experiments with also three replicates were conducted at each site. The degree of macropore flow (i.e., parameters of macropore flow) was highest at the OOF, intermediate at the YOF, and minimal at the USL. The macropore flow fraction (i.e., fraction of total infiltration flows through macropore flow pathways) at the OOF was 3.4 times greater than at the USL. The heterogeneous infiltration pattern at the OOF was dominated by macropore flow, while funnel flow was predominant at the USL. Long-term irrigation with silt-laden river water has increased silt + clay contents of the oasis soils. Irrigation and high-input crop cultivation also increased organic matter. These changes in soil properties contributed to the interaggregate voids formation. The conversion of native desert soils to irrigated croplands increases the degree of macropore flow, which might enhance groundwater recharge in the desert-oasis ecotone.

  12. Meta-analysis on Macropore Flow Velocity in Soils

    NASA Astrophysics Data System (ADS)

    Liu, D.; Gao, M.; Li, H. Y.; Chen, X.; Leung, L. R.

    2017-12-01

    Macropore flow is ubiquitous in the soils and an important hydrologic process that is not well explained using traditional hydrologic theories. Macropore Flow Velocity (MFV) is an important parameter used to describe macropore flow and quantify its effects on runoff generation and solute transport. However, the dominant factors controlling MFV are still poorly understood and the typical ranges of MFV measured at the field are not defined clearly. To address these issues, we conducted a meta-analysis based on a database created from 246 experiments on MFV collected from 76 journal articles. For a fair comparison, a conceptually unified definition of MFV is introduced to convert the MFV measured with different approaches and at various scales including soil core, field, trench or hillslope scales. The potential controlling factors of MFV considered include scale, travel distance, hydrologic conditions, site factors, macropore morphologies, soil texture, and land use. The results show that MFV is about 2 3 orders of magnitude larger than the corresponding values of saturated hydraulic conductivity. MFV is much larger at the trench and hillslope scale than at the field profile and soil core scales and shows a significant positive correlation with the travel distance. Generally, higher irrigation intensity tends to trigger faster MFV, especially at field profile scale, where MFV and irrigation intensity have significant positive correlation. At the trench and hillslope scale, the presence of large macropores (diameter>10 mm) is a key factor determining MFV. The geometric mean of MFV for sites with large macropores was found to be about 8 times larger than those without large macropores. For sites with large macropores, MFV increases with the macropore diameter. However, no noticeable difference in MFV has been observed among different soil texture and land use. Comparing the existing equations to describe MFV, the Poiseuille equation significantly overestimated the

  13. Polyacrylonitrile-Derived Sponge-Like Micro/Macroporous Carbon for Selective CO2 Separation.

    PubMed

    Guo, Li-Ping; Hu, Qing-Tao; Zhang, Peng; Li, Wen-Cui; Lu, An-Hui

    2018-06-12

    CO 2 capture under a dynamical flow situation requires adsorbents possessing balanced proportion of macropores as diffusion path and micropores as adsorption reservoir. However, the construction of interconnected micro-/macropores structure coupled with abundant nitrogen species into one carbon skeleton remains a challenge. Here, we report a new approach to prepare sponge-like carbon with a well-developed micro-/macroporous structure and enriched nitrogen species through aqueous phase polymerization of acrylonitrile in the presence of graphene oxide. The tension stress caused by the uniform thermal shrinkage of polyacrylonitrile during the pyrolysis together with the favorable flexibility of graphene oxide sheets are responsible for the formation of the sponge-like morphology. The synergistic effect of micro-/macroporous framework and rich CO 2 -philic site enables such carbon to decrease resistance to mass transfer and show high CO 2 dynamic selectivity over N 2 (454) and CH 4 (11), as well as good CO 2 capacity at 298 K under low CO 2 partial pressure (0.17 bar, a typical CO 2 partial pressure in flue gas). The above attributes make this porous carbon a promising candidate for CO 2 capture from flue gas, methane sources and other relevant applications. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Spatial structure and scaling of macropores in hydrological process at small catchment scale

    NASA Astrophysics Data System (ADS)

    Silasari, Rasmiaditya; Broer, Martine; Blöschl, Günter

    2013-04-01

    During rainfall events, the formation of overland flow can occur under the circumstances of saturation excess and/or infiltration excess. These conditions are affected by the soil moisture state which represents the soil water content in micropores and macropores. Macropores act as pathway for the preferential flows and have been widely studied locally. However, very little is known about their spatial structure and conductivity of macropores and other flow characteristic at the catchment scale. This study will analyze these characteristics to better understand its importance in hydrological processes. The research will be conducted in Petzenkirchen Hydrological Open Air Laboratory (HOAL), a 64 ha catchment located 100 km west of Vienna. The land use is divided between arable land (87%), pasture (5%), forest (6%) and paved surfaces (2%). Video cameras will be installed on an agricultural field to monitor the overland flow pattern during rainfall events. A wireless soil moisture network is also installed within the monitored area. These field data will be combined to analyze the soil moisture state and the responding surface runoff occurrence. The variability of the macropores spatial structure of the observed area (field scale) then will be assessed based on the topography and soil data. Soil characteristics will be supported with laboratory experiments on soil matrix flow to obtain proper definitions of the spatial structure of macropores and its variability. A coupled physically based distributed model of surface and subsurface flow will be used to simulate the variability of macropores spatial structure and its effect on the flow behaviour. This model will be validated by simulating the observed rainfall events. Upscaling from field scale to catchment scale will be done to understand the effect of macropores variability on larger scales by applying spatial stochastic methods. The first phase in this study is the installation and monitoring configuration of video

  15. [Soil macropore characteristics under typical vegetations in Liupan Mountains].

    PubMed

    Shi, Zhong-Jie; Wang, Yan-Hui; Xu, Li-Hong; Yu, Peng-Tao; Xiong, Wei; Xu, Da-Ping

    2007-12-01

    The radius and density of soil macropores under eight typical vegetations in Liupan Mountains of Northwest China were studied by using water breakthrough curves and Poiseuille equation. The results indicated that the radii of soil macropores ranged from 0.4 mm to 2.3 mm, and the weighted mean radii ranged from 0.57 mm to 1.21 mm, with a mean of 0.89 mm. The density of soil macropores ranged from 57 individuals per dm2 to 1 117 individuals per dm2, with a mean of 408 individuals per dm2. The macropores with radii bigger than 1.4 mm had a lower density, accounting for only 6.86% of the total. The area proportion of soil macropores ranged from 0.76% to 31.26%, with a mean of 10.82%. In study area, the density of soil macropores was higher in broadleaf forest than in coniferous forest, but basically the same in sub-alpine meadow and in broadleaf forest, as well as in shrubs and in coniferous forest. As for the area proportion of soil macropores, it was also higher in broadleaf forest than in coniferous forest, but basically the same in shrubs and in broadleaf forest soil, as well as in sub-alpine meadow and in coniferous forest.

  16. Controlled release of ibuprofen by meso–macroporous silica

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

    Santamaría, E., E-mail: esthersantamaria@ub.edu; Maestro, A.; Porras, M.

    2014-02-15

    Structured meso–macroporous silica was successfully synthesized from an O/W emulsion using decane as a dispersed phase. Sodium silicate solution, which acts as a silica source and a poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) (EO{sub 19}PO{sub 39}EO{sub 19}) denoted as P84 was used in order to stabilize the emulsion and as a mesopore template. The materials obtained were characterized through transmission electron microscopy (TEM), scanning electron microscopy (SEM), small-angle X-ray diffraction scattering (SAXS) and nitrogen adsorption–desorption isotherms. Ibuprofen (IBU) was selected as the model drug and loaded into ordered meso–macroporous materials. The effect of the materials’ properties on IBU drug loading and releasemore » was studied. The results showed that the loading of IBU increases as the macropore presence in the material is increased. The IBU adsorption process followed the Langmuir adsorption isotherm. A two-step release process, consisting of an initial fast release and then a slower release was observed. Macropores enhanced the adsorption capacity of the material; this was probably due to the fact that they allowed the drug to access internal pores. When only mesopores were present, ibuprofen was probably adsorbed on the mesopores close to the surface. Moreover, the more macropore present in the material, the slower the release behaviour observed, as the ibuprofen adsorbed in the internal pores had to diffuse along the macropore channels up to the surface of the material. The material obtained from a highly concentrated emulsion was functionalized with amino groups using two methods, the post-grafting mechanism and the co-condensation mechanism. Both routes improve IBU adsorption in the material and show good behaviour as a controlled drug delivery system. - Graphical abstract: Ibuprofen release profiles for the materials obtained from samples P84{sub m}eso (black diamonds), P84{sub 2}0% (white squares), P84

  17. Predicting macropores in space and time by earthworms and abiotic controls

    NASA Astrophysics Data System (ADS)

    Hohenbrink, Tobias Ludwig; Schneider, Anne-Kathrin; Zangerlé, Anne; Reck, Arne; Schröder, Boris; van Schaik, Loes

    2017-04-01

    Macropore flow increases infiltration and solute leaching. The macropore density and connectivity, and thereby the hydrological effectiveness, vary in space and time due to earthworms' burrowing activity and their ability to refill their burrows in order to survive drought periods. The aim of our study was to predict the spatiotemporal variability of macropore distributions by a set of potentially controlling abiotic variables and abundances of different earthworm species. We measured earthworm abundances and effective macropore distributions using tracer rainfall infiltration experiments in six measurement campaigns during one year at six field sites in Luxembourg. Hydrologically effective macropores were counted in three soil depths (3, 10, 30 cm) and distinguished into three diameter classes (<2, 2-6, >6 mm). Earthworms were sampled and determined to species-level. In a generalized linear modelling framework, we related macropores to potential spatial and temporal controlling factors. Earthworm species such as Lumbricus terrestris and Aporrectodea longa, local abiotic site conditions (land use, TWI, slope), temporally varying weather conditions (temperature, humidity, precipitation) and soil moisture affected the number of effective macropores. Main controlling factors and explanatory power of the models (uncertainty and model performance) varied depending on the depth and diameter class of macropores. We present spatiotemporal predictions of macropore density by daily-resolved, one year time series of macropore numbers and maps of macropore distributions at specific dates in a small-scale catchment with 5 m resolution.

  18. Spherical Macroporous Carbon Nanotube Particles with Ultrahigh Sulfur Loading for Lithium-Sulfur Battery Cathodes.

    PubMed

    Gueon, Donghee; Hwang, Jeong Tae; Yang, Seung Bo; Cho, Eunkyung; Sohn, Kwonnam; Yang, Doo-Kyung; Moon, Jun Hyuk

    2018-01-23

    A carbon host capable of effective and uniform sulfur loading is the key for lithium-sulfur batteries (LSBs). Despite the application of porous carbon materials of various morphologies, the carbon hosts capable of uniformly impregnating highly active sulfur is still challenging. To address this issue, we demonstrate a hierarchical pore-structured CNT particle host containing spherical macropores of several hundred nanometers. The macropore CNT particles (M-CNTPs) are prepared by drying the aerosol droplets in which CNTs and polymer particles are dispersed. The spherical macropore greatly improves the penetration of sulfur into the carbon host in the melt diffusion of sulfur. In addition, the formation of macropores greatly develops the volume of the micropore between CNT strands. As a result, we uniformly impregnate 70 wt % sulfur without sulfur residue. The S-M-CNTP cathode shows a highly reversible capacity of 1343 mA h g -1 at a current density of 0.2 C even at a high sulfur content of 70 wt %. Upon a 10-fold current density increase, a high capacity retention of 74% is observed. These cathodes have a higher sulfur content than those of conventional CNT hosts but nevertheless exhibit excellent performance. Our CNTPs and pore control technology will advance the commercialization of CNT hosts for LSBs.

  19. Quantifying macropore recharge: Examples from a semi-arid area

    USGS Publications Warehouse

    Wood, W.W.; Rainwater, Ken A.; Thompson, D.B.

    1997-01-01

    The purpose of this paper is to illustrate the significantly increased resolution of determining macropore recharge by combining physical, chemical, and isotopic methods of analysis. Techniques for quantifying macropore recharge were developed for both small-scale (1 to 10 km2) and regional-scale areas in and semi-arid areas. The Southern High Plains region of Texas and New Mexico was used as a representative field site to test these methods. Macropore recharge in small-scale areas is considered to be the difference between total recharge through floors of topographically dosed basins and interstitial recharge through the same area. On the regional scale, macropore recharge was considered to be the difference between regional average annual recharge and interstitial recharge measured in the unsaturated zone. Stable isotopic composition of ground water and precipitation was used us an independent estimate of macropore recharge on the regional scale. Results of this analysis suggest that in the Southern High Plains recharge flux through macropores is between 60 and 80 percent of the total 11 mm/y. Between 15 and 35 percent of the recharge occurs by interstitial recharge through the basin floors. Approximately 5 percent of the total recharge occurs as either interstitial or matrix recharge between the basin floors, representing approximately 95 percent of the area. The approach is applicable to other arid and semi-arid areas that focus rainfall into depressions or valleys.The purpose of this paper is to illustrate the significantly increased resolution of determining macropore recharge by combining physical, chemical, and isotopic methods of analysis. Techniques for quantifying macropore recharge were developed for both small-scale (1 to 10 km2) and regional-scale areas in arid and semi-arid areas. The Southern High Plains region of Texas and New Mexico was used as a representative field site to test these methods. Macropore recharge in small-scale areas is considered

  20. Modified APEX model for Simulating Macropore Phosphorus Contributions to Tile Drains.

    PubMed

    Ford, William I; King, Kevin W; Williams, Mark R; Confesor, Remegio B

    2017-11-01

    The contribution of macropore flow to phosphorus (P) loadings in tile-drained agricultural landscapes remains poorly understood at the field scale, despite the recognized deleterious impacts of contaminant transport via macropore pathways. A new subroutine that couples existing matrix-excess and matrix-desiccation macropore flow theory and a modified P routine is implemented in the Agricultural Policy Environmental eXtender (APEX) model. The original and modified formulation were applied and evaluated for a case study in a poorly drained field in Western Ohio with 31 months of surface and subsurface monitoring data. Results highlighted that a macropore subroutine in APEX improved edge-of-field discharge calibration and validation for both tile and total discharge from satisfactory and good, respectively, to very good and improved dissolved reactive P load calibration and validation statistics for tile P loads from unsatisfactory to very good. Output from the calibrated macropore simulations suggested median annual matrix-desiccation macropore flow contributions of 48% and P load contributions of 43%, with the majority of loading occurring in winter and spring. While somewhat counterintuitive, the prominence of matrix-desiccation macropore flow during seasons with less cracking reflects the importance of coupled development of macropore pathways and adequate supply of the macropore flow source. The innovative features of the model allow for assessments of annual macropore P contributions to tile drainage and has the potential to inform P site assessment tools. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. Abnormally high formation pressures, Potwar Plateau, Pakistan

    USGS Publications Warehouse

    Law, B.E.; Shah, S.H.A.; Malik, M.A.

    1998-01-01

    Abnormally high formation pressures in the Potwar Plateau of north-central Pakistan are major obstacles to oil and gas exploration. Severe drilling problems associated with high pressures have, in some cases, prevented adequate evaluation of reservoirs and significantly increased drilling costs. Previous investigations of abnormal pressure in the Potwar Plateau have only identified abnormal pressures in Neogene rocks. We have identified two distinct pressure regimes in this Himalayan foreland fold and thrust belt basin: one in Neogene rocks and another in pre-Neogene rocks. Pore pressures in Neogene rocks are as high as lithostatic and are interpreted to be due to tectonic compression and compaction disequilibrium associated with high rates of sedimentation. Pore pressure gradients in pre-Neogene rocks are generally less than those in Neogene rocks, commonly ranging from 0.5 to 0.7 psi/ft (11.3 to 15.8 kPa/m) and are most likely due to a combination of tectonic compression and hydrocarbon generation. The top of abnormally high pressure is highly variable and doesn't appear to be related to any specific lithologic seal. Consequently, attempts to predict the depth to the top of overpressure prior to drilling are precluded.

  2. Biomimetic macroporous hydrogel scaffolds in a high-throughput screening format for cell-based assays.

    PubMed

    Dainiak, Maria B; Savina, Irina N; Musolino, Isabella; Kumar, Ashok; Mattiasson, Bo; Galaev, Igor Yu

    2008-01-01

    Macroporous hydrogels (MHs) hold great promise as scaffolds in tissue engineering and cell-based assays. In this study, the possibility of combination of three-dimensional (3D) cell culture with a miniaturized screening format was demonstrated on human colon cancer HCT116, human acute myeloid leukemia KG-1 cells, and embryonic fibroblasts cultured on MHs (12.5 mm x 7.1 mm I.D.) in a 96-minicolumn plate format. MHs were prepared by cryogelation technique and functionalized by coating with type I collagen and by copolymerization with agmatine-based mimetic of cell adhesive peptide RGD (abRGDm). Cancer cells formed multicellular aggregates while fibroblasts formed adhesions on abRGDm-containing and collagen-MHs but not on plain MHs, as was demonstrated by scanning electron microscopy. HCT116 and KG-1 cells grown as aggregates were more resistant to the treatment with cis-diaminedichloroplatinum (II) (cisplatin) and cytosine 1-beta-D-arabinofuranoside (Ara-C), respectively, during the first 18-24 h of incubation, than single cells grown on unmodified MH. HCT116 cells grown as 2D cultures in conventional 96-well tissue culture plates were 1.5- to 3.5-fold more sensitive to the treatment with 70 microM cisplatin than cells in 3D cultures in functionalized MHs. Further development of the described experimental system including matching of a specific cell type with appropriate extracellular matrix (ECM) components and 3D cocultures on ECM-modified MHs may provide a realistic in vitro experimental model for high-throughput toxicity tests.

  3. Conjunction of Conducting Polymer Nanostructures with Macroporous Structured Graphene Thin Films for High-Performance Flexible Supercapacitors.

    PubMed

    Memon, Mushtaque A; Bai, Wei; Sun, Jinhua; Imran, Muhammad; Phulpoto, Shah Nawaz; Yan, Shouke; Huang, Yong; Geng, Jianxin

    2016-05-11

    Fabrication of hybridized structures is an effective strategy to promote the performances of graphene-based composites for energy storage/conversion applications. In this work, macroporous structured graphene thin films (MGTFs) are fabricated on various substrates including flexible graphene papers (GPs) through an ice-crystal-induced phase separation process. The MGTFs prepared on GPs (MGTF@GPs) are recognized with remarkable features such as interconnected macroporous configuration, sufficient exfoliation of the conductive RGO sheets, and good mechanical flexibility. As such, the flexible MGTF@GPs are demonstrated as a versatile conductive platform for depositing conducting polymers (CPs), e.g., polyaniline (PAn), polypyrrole, and polythiophene, through in situ electropolymerization. The contents of the CPs in the composite films are readily controlled by varying the electropolymerization time. Notably, electrodeposition of PAn leads to the formation of nanostructures of PAn nanofibers on the walls of the macroporous structured RGO framework (PAn@MGTF@GPs): thereafter, the PAn@MGTF@GPs display a unique structural feature that combine the nanostructures of PAn nanofibers and the macroporous structures of RGO sheets. Being used as binder-free electrodes for flexible supercapacitors, the PAn@MGTF@GPs exhibit excellent electrochemical performance, in particular a high areal specific capacity (538 mF cm(-2)), high cycling stability, and remarkable capacitive stability to deformation, due to the unique electrode structures.

  4. Controlled release of ibuprofen by meso-macroporous silica

    NASA Astrophysics Data System (ADS)

    Santamaría, E.; Maestro, A.; Porras, M.; Gutiérrez, J. M.; González, C.

    2014-02-01

    Structured meso-macroporous silica was successfully synthesized from an O/W emulsion using decane as a dispersed phase. Sodium silicate solution, which acts as a silica source and a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (EO19PO39EO19) denoted as P84 was used in order to stabilize the emulsion and as a mesopore template. The materials obtained were characterized through transmission electron microscopy (TEM), scanning electron microscopy (SEM), small-angle X-ray diffraction scattering (SAXS) and nitrogen adsorption-desorption isotherms. Ibuprofen (IBU) was selected as the model drug and loaded into ordered meso-macroporous materials. The effect of the materials’ properties on IBU drug loading and release was studied. The results showed that the loading of IBU increases as the macropore presence in the material is increased. The IBU adsorption process followed the Langmuir adsorption isotherm. A two-step release process, consisting of an initial fast release and then a slower release was observed. Macropores enhanced the adsorption capacity of the material; this was probably due to the fact that they allowed the drug to access internal pores. When only mesopores were present, ibuprofen was probably adsorbed on the mesopores close to the surface. Moreover, the more macropore present in the material, the slower the release behaviour observed, as the ibuprofen adsorbed in the internal pores had to diffuse along the macropore channels up to the surface of the material. The material obtained from a highly concentrated emulsion was functionalized with amino groups using two methods, the post-grafting mechanism and the co-condensation mechanism. Both routes improve IBU adsorption in the material and show good behaviour as a controlled drug delivery system.

  5. Relations between macropore network characteristics and the degree of preferential solute transport

    NASA Astrophysics Data System (ADS)

    Larsbo, M.; Koestel, J.; Jarvis, N.

    2014-12-01

    The characteristics of the soil macropore network determine the potential for fast transport of agrochemicals and contaminants through the soil. The objective of this study was to examine the relationships between macropore network characteristics, hydraulic properties and state variables and measures of preferential transport. Experiments were carried out under near-saturated conditions on undisturbed columns sampled from four agricultural topsoils of contrasting texture and structure. Macropore network characteristics were computed from 3-D X-ray tomography images of the soil pore system. Non-reactive solute transport experiments were carried out at five steady-state water flow rates from 2 to 12 mm h-1. The degree of preferential transport was evaluated by the normalised 5% solute arrival time and the apparent dispersivity calculated from the resulting breakthrough curves. Near-saturated hydraulic conductivities were measured on the same samples using a tension disc infiltrometer placed on top of the columns. Results showed that many of the macropore network characteristics were inter-correlated. For example, large macroporosities were associated with larger specific macropore surface areas and better local connectivity of the macropore network. Generally, an increased flow rate resulted in earlier solute breakthrough and a shifting of the arrival of peak concentration towards smaller drained volumes. Columns with smaller macroporosities, poorer local connectivity of the macropore network and smaller near-saturated hydraulic conductivities exhibited a greater degree of preferential transport. This can be explained by the fact that, with only two exceptions, global (i.e. sample scale) continuity of the macropore network was still preserved at low macroporosities. Thus, for any given flow rate, pores of larger diameter were actively conducting solute in soils of smaller near-saturated hydraulic conductivity. This was associated with larger local transport

  6. Macroporous Monolithic Polymers: Preparation and Applications

    PubMed Central

    Arrua, Ruben Dario; Strumia, Miriam Cristina; Alvarez Igarzabal, Cecilia Inés

    2009-01-01

    In the last years, macroporous monolithic materials have been introduced as a new and useful generation of polymers used in different fields. These polymers may be prepared in a simple way from a homogenous mixture into a mold and contain large interconnected pores or channels allowing for high flow rates at moderate pressures. Due to their porous characteristics, they could be used in different processes, such as stationary phases for different types of chromatography, high-throughput bioreactors and in microfluidic chip applications. This review reports the contributions of several groups working in the preparation of different macroporous monoliths and their modification by immobilization of specific ligands on the products for specific purposes.

  7. Nonenzymatic free-cholesterol detection via a modified highly sensitive macroporous gold electrode with platinum nanoparticles.

    PubMed

    Lee, Yi-Jae; Park, Jae-Yeong

    2010-12-15

    A sensitive macroporous Au electrode with a highly rough surface obtained through the use of with Pt nanoparticles (macroporous Au-/nPts) is reported. It has been designed for nonenzymatic free-cholesterol biosensor applications. A macroporous Au-/nPts electrode was fabricated by electroplating Pt nanoparticles onto a coral-like shaped macroporous Au electrode structure. The macroporous Au-/nPts electrode was physically characterized by field emission scanning electron microscopy (FESEM). It was confirmed that the Pt nanoparticles were well deposited on the surface of the macroporous Au electrode. The porosity and window pore size of the macroporous Au electrode were 50% and 100-300 nm, respectively. The electroplated Pt nanoparticle size was approximately 10-20 nm. Electrochemical experiments showed that the macroporous Au-/nPts exhibited a much larger surface activation area (roughness factor (RF)=2024.7) than the macroporous Au electrode (RF=46.07). The macroporous Au-/nPts also presented a much stronger electrocatalytic activity towards cholesterol oxidation than does the macroporous Au electrode. At 0.2 V, the electrode responded linearly up to a 5 mM cholesterol concentration in a neutral media, with a detection limit of 0.015 mM and detection sensitivity of 226.2 μA mM(-1) cm(-2). Meanwhile, interfering species such as ascorbic acid (AA), acetaminophen (AP), and uric acid (UA), were effectively avoided. This novel nonenzymatic detection electrode has strong applications as an electrochemically based cholesterol biosensor. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. Soft-Template Construction of 3D Macroporous Polypyrrole Scaffolds.

    PubMed

    Liu, Shaohua; Wang, Faxing; Dong, Renhao; Zhang, Tao; Zhang, Jian; Zheng, Zhikun; Mai, Yiyong; Feng, Xinliang

    2017-04-01

    A bottom-up approach toward 3D hierarchical macroporous polypyrrole aerogels is demonstrated via soft template-directed synthesis and self-assembly of ultrathin polypyrrole nanosheets in solution, which present interconnected macropores, ultrathin walls, and large specific surface areas, thereby exhibiting a high capacity, satisfactory rate capability, and excellent cycling stability for Na-ion storage. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Formation of different micro-morphologies from VO2 and ZnO crystallization using macro-porous silicon substrates

    NASA Astrophysics Data System (ADS)

    Salazar-Kuri, U.; Antúnez, E. E.; Estevez, J. O.; Olive-Méndez, Sion F.; Silva-González, N. R.; Agarwal, V.

    2017-05-01

    Square-shaped macropores produced by electrochemical anodization of n- and p-type Si wafers have been used as centers of nucleation to crystallize VO2 and ZnO. Substrate roughness dependent formation of different morphologies is revealed in the form of squared particles, spheres, bars and ribbons in the case of VO2 and hexagonal piles and spheres in the case of ZnO, have been observed.The presence of nano-/micro-metric crystals was studied through field emission scanning electron microscopy and energy dispersive X-ray spectroscopy mapping. Crystal structure of metal oxides was confirmed by micro-Raman spectroscopy. The growth of the different morphologies has been explained in terms of the surface free energy of a bare Si/SiO2 substrate and its modification originated from the roughness of the surface and of the walls of the porous substrates. This energy plays a crucial role on the minimization of the required energy to induce heterogeneous nucleation and crystal growth. Present work strengthens and provides an experimental evidence of roughness dependent metal oxide crystal growth with well-defined habits from pore corners and rough sides of the pore walls, similar to already reported protein crystals.

  10. Mapping Soil Surface Macropores Using Infrared Thermography: An Exploratory Laboratory Study

    PubMed Central

    de Lima, João L. M. P.; Abrantes, João R. C. B.; Silva, Valdemir P.; de Lima, M. Isabel P.; Montenegro, Abelardo A. A.

    2014-01-01

    Macropores and water flow in soils and substrates are complex and are related to topics like preferential flow, nonequilibrium flow, and dual-continuum. Hence, the quantification of the number of macropores and the determination of their geometry are expected to provide a better understanding on the effects of pores on the soil's physical and hydraulic properties. This exploratory study aimed at evaluating the potential of using infrared thermography for mapping macroporosity at the soil surface and estimating the number and size of such macropores. The presented technique was applied to a small scale study (laboratory soil flume). PMID:25371915

  11. [Monitoring method for macroporous resin column chromatography process of salvianolic acids based on near infrared spectroscopy].

    PubMed

    Hou, Xiang-Mei; Zhang, Lei; Yue, Hong-Shui; Ju, Ai-Chun; Ye, Zheng-Liang

    2016-07-01

    To study and establish a monitoring method for macroporous resin column chromatography process of salvianolic acids by using near infrared spectroscopy (NIR) as a process analytical technology (PAT).The multivariate statistical process control (MSPC) model was developed based on 7 normal operation batches, and 2 test batches (including one normal operation batch and one abnormal operation batch) were used to verify the monitoring performance of this model. The results showed that MSPC model had a good monitoring ability for the column chromatography process. Meanwhile, NIR quantitative calibration model was established for three key quality indexes (rosmarinic acid, lithospermic acid and salvianolic acid B) by using partial least squares (PLS) algorithm. The verification results demonstrated that this model had satisfactory prediction performance. The combined application of the above two models could effectively achieve real-time monitoring for macroporous resin column chromatography process of salvianolic acids, and can be used to conduct on-line analysis of key quality indexes. This established process monitoring method could provide reference for the development of process analytical technology for traditional Chinese medicines manufacturing. Copyright© by the Chinese Pharmaceutical Association.

  12. Characteristics of immobilized aminoacylase from Aspergillus oryzae on macroporous copolymers.

    PubMed

    He, B L; Jiang, P; Qiu, Y B

    1990-01-01

    Aminoacylase from Aspergillus oryzae was adsorbed on functionallized macroporous copolymers where the enzyme showed excellent catalyzing activity and operation stability. Various factors which effect the activity of the immobilized aminoacylase such as temperature, pH and ionic strength were investigated. The continuous operation of the enzyme immobilized on macroporous copolymers was compared with that of the enzyme immobilized on DEAE-Sephadex.

  13. Representing macropore flow at the catchment scale: a comparative modeling study

    NASA Astrophysics Data System (ADS)

    Liu, D.; Li, H. Y.; Tian, F.; Leung, L. R.

    2017-12-01

    Macropore flow is an important hydrological process that generally enhances the soil infiltration capacity and velocity of subsurface water. Up till now, macropore flow is mostly simulated with high-resolution models. One possible drawback of this modeling approach is the difficulty to effectively represent the overall typology and connectivity of the macropore networks. We hypothesize that modeling macropore flow directly at the catchment scale may be complementary to the existing modeling strategy and offer some new insights. Tsinghua Representative Elementary Watershed model (THREW model) is a semi-distributed hydrology model, where the fundamental building blocks are representative elementary watersheds (REW) linked by the river channel network. In THREW, all the hydrological processes are described with constitutive relationships established directly at the REW level, i.e., catchment scale. In this study, the constitutive relationship of macropore flow drainage is established as part of THREW. The enhanced THREW model is then applied at two catchments with deep soils but distinct climates, the humid Asu catchment in the Amazon River basin, and the arid Wei catchment in the Yellow River basin. The Asu catchment has an area of 12.43km2 with mean annual precipitation of 2442mm. The larger Wei catchment has an area of 24800km2 but with mean annual precipitation of only 512mm. The rainfall-runoff processes are simulated at a hourly time step from 2002 to 2005 in the Asu catchment and from 2001 to 2012 in the Wei catchment. The role of macropore flow on the catchment hydrology will be analyzed comparatively over the Asu and Wei catchments against the observed streamflow, evapotranspiration and other auxiliary data.

  14. Macroporous nanowire nanoelectronic scaffolds for synthetic tissues

    NASA Astrophysics Data System (ADS)

    Tian, Bozhi; Liu, Jia; Dvir, Tal; Jin, Lihua; Tsui, Jonathan H.; Qing, Quan; Suo, Zhigang; Langer, Robert; Kohane, Daniel S.; Lieber, Charles M.

    2012-11-01

    The development of three-dimensional (3D) synthetic biomaterials as structural and bioactive scaffolds is central to fields ranging from cellular biophysics to regenerative medicine. As of yet, these scaffolds cannot electrically probe the physicochemical and biological microenvironments throughout their 3D and macroporous interior, although this capability could have a marked impact in both electronics and biomaterials. Here, we address this challenge using macroporous, flexible and free-standing nanowire nanoelectronic scaffolds (nanoES), and their hybrids with synthetic or natural biomaterials. 3D macroporous nanoES mimic the structure of natural tissue scaffolds, and they were formed by self-organization of coplanar reticular networks with built-in strain and by manipulation of 2D mesh matrices. NanoES exhibited robust electronic properties and have been used alone or combined with other biomaterials as biocompatible extracellular scaffolds for 3D culture of neurons, cardiomyocytes and smooth muscle cells. Furthermore, we show the integrated sensory capability of the nanoES by real-time monitoring of the local electrical activity within 3D nanoES/cardiomyocyte constructs, the response of 3D-nanoES-based neural and cardiac tissue models to drugs, and distinct pH changes inside and outside tubular vascular smooth muscle constructs.

  15. A New Model for Root Growth in Soil with Macropores

    NASA Astrophysics Data System (ADS)

    Landl, M.; Huber, K.; Schnepf, A.; Vanderborght, J.; Javaux, M.; Bengough, G.; Vereecken, H.

    2016-12-01

    In order to study soil-root interaction processes, dynamic root architecture models which are linked to models that simulate water flow and nutrient transport in the soil-root system are needed. Such models can be used to predict the impact of soil structural features, e.g. the presence of macropores in dense subsoil, on water and nutrient uptake by plants. In dynamic root architecture models, root growth is represented by moving root tips whose growth trajectory results in the creation of linear root segments. Typically, the direction of each new root segment is calculated as the vector sum of various direction-affecting components. The use of these established methods to simulate root growth in soil containing macropores, however, failed to reproduce experimentally observed root growth patterns. We therefore developed an alternative modelling approach where we distinguish between, firstly, the driving force for root growth which is determined by the orientation of the previous root segment as well as the influence of gravitropism and, secondly, soil mechanical resistance to root growth. The latter is expressed by root conductance which represents the inverse of soil penetration resistance and is treated similarly to hydraulic conductivity in Darcy's law. At the presence of macropores, root conductance is anisotropic which leads to a difference between the direction of the driving force and the direction of the root tip movement. The model was tested using data from the literature, at pot scale, at macropore scale, and in a series of simulations where sensitivity to gravity and macropore orientation was evaluated. The model simulated root growth trajectories in structured soil at both single root and whole root-system scales, generating root systems that were similar to images from experiments. Its implementation in the three dimensional soil and root water uptake model R-SWMS enables the use of the model in the future to evaluate the effect of macropores on crop

  16. Synthesis of hierarchically meso-macroporous TiO2/CdS heterojunction photocatalysts with excellent visible-light photocatalytic activity.

    PubMed

    Zhao, Haixin; Cui, Shu; Yang, Lan; Li, Guodong; Li, Nan; Li, Xiaotian

    2018-02-15

    Photocatalysts with a hierarchically porous structure have attracted considerable attention owing to their wide pore size distribution and high surface area, which enhance the efficiency of transporting species to active sites. In this study, hierarchically meso-macroporous TiO 2 photocatalysts decorated with highly dispersed CdS nanoparticles were synthesized via hydrolysis, followed by a hydrothermal treatment. The textural mesopores and interconnected pore framework provided more accessible active sites and efficient mass transport for the photocatalytic process. The light collection efficiency was enhanced because of multiple scattering of incident light in the macropores. Moreover, the formation of a heterojunction between the CdS and TiO 2 nanoparticles extended the photoresponse of TiO 2 to the visible-light range and enhanced the charge separation efficiency. Therefore, the hierarchically meso-macroporous TiO 2 /CdS photocatalysts exhibited excellent photocatalytic activity for the degradation of rhodaming B under visible-light irradiation. Trapping experiments demonstrated that superoxide radicals (O 2 - ) and hydroxyl radicals (OH) were the main active species in photocatalysis. A reasonable photocatalytic mechanism of TiO 2 /CdS heterojunction photocatalysts was also presented. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Effect of tillage on macropore flow and phosphorus transport to tile drains

    USDA-ARS?s Scientific Manuscript database

    Elevated phosphorus (P) concentrations in subsurface drainage water are thought to be the result of P bypassing the soil matrix via macropore flow. The objectives of this study were to quantify event water delivery to tile drains via macropore flow paths during storm events and to determine the effe...

  18. Macropore system characteristics controls on non-reactive solute transport at different flow rates

    NASA Astrophysics Data System (ADS)

    Larsbo, Mats; Koestel, John

    2014-05-01

    Preferential flow and transport in macroporous soils are important pathways for the leaching of agrochemicals through soils. Preferential solute transport in soil is to a large extent determined by the macropore system characteristics and the water flow conditions. The importance of different characteristics of the macropore system is likely to vary with the flow conditions. The objective of this study was to determine which properties of the macropore system that control the shape of non-reactive tracer solute breakthrough curves at different steady-state flow rates. We sampled five undisturbed columns (20 cm high, 20 cm diameter) from the soil surface of four soils with clay contents between 21 and 50 %. Solute transport experiments were carried out under unsaturated conditions at 2, 4, 6, 8 and 12 mm h-1 flow rates. For each flow rate a pulse of potassium bromide solution was applied at the soil surface and the electrical conductivity was measured with high temporal resolution in the column effluent. We used the 5 % arrival time and the holdback factor to estimate the degree of preferential transport from the resulting breakthrough curves. Unsaturated hydraulic conductivities were measured at the soil surface of the columns using a tension disc infiltrometer. The macropore system was imaged by industrial X-ray computed tomography at a resolution of 125 μm in all directions. Measures of the macropore system characteristics including measures of pore continuity were calculated from these images using the ImageJ software. Results show that the degree of preferential transport is generally increasing with flow rate when larger pores become active in the transport. The degree of preferential flow was correlated to measures of macropore topology. This study show that conclusions drawn from experiments carried out at one flow rate should generally not be extrapolated to other flow rates.

  19. [Studies on the process of Herba Clinopodii saponins purified with macroporous adsorption resin].

    PubMed

    Zhang, Yi; Yan, Dan; Han, Yumei

    2005-10-01

    To study the technological parameters of the purification process of saponins with macroporous adsorption resin. The adsorptive characteristics and elutive parameters of the process were studied by taking the elutive and purified ratio of saponins as markers. 11.4 ml of the extraction of Herba Clinopodii (crude drugs 0.2 g/ml) was purified with a column of macroporous adsorption resin (phi15 mm x H90 mm, dry weight 2.5 g) and washed with 3BV of distilled water, then eluted with 3BV of 30% ethanol and 3BV of 70% ethanol. Most of saponins were collected in the 70% ethanol. With macroporous adsorption resin adsorbing and purifying,the elutive ratio of saponins is 86.8% and the purity reaches 153.2%. So this process of applying macroporous adsorption resin to adsorb and purify Saponins is feasible.

  20. Nature and extent of macropores in forest soils and their influence on subsurface water movement

    Treesearch

    Gerald M. Aubertin; Gerald M. Aubertin

    1971-01-01

    Rain, falling on a sloping forested soil, may enter the soil quickly and move considerable distances through the soil by way of macropores. A macropore is a large pore, cavity, passageway, channel, tunnel, or void in the soil, through which water usually drains by gravity. Large quantities of water can move through the soil by way of these macropores-without...

  1. Facile Fabrication of Microparticles with pH-responsive Macropores for Small Intestine Targeted Drug Formulation.

    PubMed

    Homayun, Bahman; Sun, Chengmeng; Kumar, Ankit; Montemagno, Carlo; Choi, Hyo-Jick

    2018-05-10

    Oral drugs present the most convenient, economical, and painless route for self-administration. Despite commercialization of multiple technologies relying on micro- and nanocrystalline drugs, research on microparticles (MPs) based oral biopharmaceuticals delivery systems has still not culminated well enough in commercial products. This is largely due to the drugs being exposed to the destabilizing environment during MP synthesis process, and partly because of complicated process conditions. Hence, we developed a solvent swelling-evaporation method of producing pH-responsive MPs with micron-sized macropores using poly(methacrylic acid-co-ethyl acrylate) in 1:1 ratio (commercial name: Eudragit ® L100-55 polymer). We investigated the effects of temperature and evaporation time on pore formation, freeze-drying induced pore closure, and the release profile of model drugs (fluorescent beads, lactase, and pravastatin sodium) encapsulated MPs in simulated gastrointestinal tract conditions. Encapsulated lactase/pravastatin maintained > 60% of their activity due to the preservation of pore closure, which proved the potential of this proof-of-concept microencapsulation system. Importantly, the presence of macropores on MPs can be beneficial for easy drug loading, and solve the problem of bioactivity loss during the conventional MP fabrication-drug encapsulation steps. Therefore, pH-sensing MPs with macropores can contribute to the development of oral drug formulations for a wide variety of drugs and bio-macromolecules, having a various size ranging from genes to micron-sized ingredients with high therapeutic efficacy. Copyright © 2018. Published by Elsevier B.V.

  2. Hierarchical mesostructured titanium phosphonates with unusual uniform lines of macropores.

    PubMed

    Ma, Tian-Yi; Lin, Xiu-Zhen; Zhang, Xue-Jun; Yuan, Zhong-Yong

    2011-04-01

    Organic-inorganic hybrid materials of mesostructured titanium phosphonates with unusual uniform lines of macropores were synthesized by using bis(hexamethylenetriamine) penta(methylenephosphonic acid) (BHMTPMP) as the coupling molecule, through a one-pot hydrothermal process without any surfactant assistance. A wormhole-like mesostructure and many uniform parallel lines of macropores divided by solid ridges in the same direction were confirmed by N(2) sorption, SEM and TEM observations. This novel macropore architecture has never been observed in other metal phosphonate materials, which may be directly related to the structure nature of BHMTPMP with extra long alkyl chains. The structural characterization of FT-IR and MAS NMR revealed the integrity of organic groups inside the hybrid framework. The hybrid materials were also used as adsorbents for heavy metal ions and CO(2), in order to clarify the impacts of the organic contents and organic types on the physicochemical properties of the synthesized hierarchical macro-/mesoporous phosphonate materials.

  3. Three-dimensional macroporous nanoelectronic networks as minimally invasive brain probes

    NASA Astrophysics Data System (ADS)

    Xie, Chong; Liu, Jia; Fu, Tian-Ming; Dai, Xiaochuan; Zhou, Wei; Lieber, Charles M.

    2015-12-01

    Direct electrical recording and stimulation of neural activity using micro-fabricated silicon and metal micro-wire probes have contributed extensively to basic neuroscience and therapeutic applications; however, the dimensional and mechanical mismatch of these probes with the brain tissue limits their stability in chronic implants and decreases the neuron-device contact. Here, we demonstrate the realization of a three-dimensional macroporous nanoelectronic brain probe that combines ultra-flexibility and subcellular feature sizes to overcome these limitations. Built-in strains controlling the local geometry of the macroporous devices are designed to optimize the neuron/probe interface and to promote integration with the brain tissue while introducing minimal mechanical perturbation. The ultra-flexible probes were implanted frozen into rodent brains and used to record multiplexed local field potentials and single-unit action potentials from the somatosensory cortex. Significantly, histology analysis revealed filling-in of neural tissue through the macroporous network and attractive neuron-probe interactions, consistent with long-term biocompatibility of the device.

  4. Organic matter composition of soil macropore surfaces under different agricultural management practices

    NASA Astrophysics Data System (ADS)

    Glæsner, Nadia; Leue, Marin; Magid, Jacob; Gerke, Horst H.

    2016-04-01

    Understanding the heterogeneous nature of soil, i.e. properties and processes occurring specifically at local scales is essential for best managing our soil resources for agricultural production. Examination of intact soil structures in order to obtain an increased understanding of how soil systems operate from small to large scale represents a large gap within soil science research. Dissolved chemicals, nutrients and particles are transported through the disturbed plow layer of agricultural soil, where after flow through the lower soil layers occur by preferential flow via macropores. Rapid movement of water through macropores limit the contact between the preferentially moving water and the surrounding soil matrix, therefore contact and exchange of solutes in the water is largely restricted to the surface area of the macropores. Organomineral complex coated surfaces control sorption and exchange properties of solutes, as well as availability of essential nutrients to plant roots and to the preferentially flowing water. DRIFT (Diffuse Reflectance infrared Fourier Transform) Mapping has been developed to examine composition of organic matter coated macropores. In this study macropore surfaces structures will be determined for organic matter composition using DRIFT from a long-term field experiment on waste application to agricultural soil (CRUCIAL, close to Copenhagen, Denmark). Parcels with 5 treatments; accelerated household waste, accelerated sewage sludge, accelerated cattle manure, NPK and unfertilized, will be examined in order to study whether agricultural management have an impact on the organic matter composition of intact structures.

  5. Spatial distribution of heterocyclic organic matter compounds at macropore surfaces in Bt-horizons

    NASA Astrophysics Data System (ADS)

    Leue, Martin; Eckhardt, Kai-Uwe; Gerke, Horst H.; Ellerbrock, Ruth H.; Leinweber, Peter

    2017-04-01

    The illuvial Bt-horizon of Luvisols is characterized by coatings of clay and organic matter (OM) at the surfaces of cracks, biopores and inter-aggregate spaces. The OM composition of the coatings that originate from preferential transport of suspended matter in macropores determines the physico-chemical properties of the macropore surfaces. The analysis of the spatial distribution of specific OM components such as heterocyclic N-compounds (NCOMP) and benzonitrile and naphthalene (BN+NA) could enlighten the effect of macropore coatings on the transport of colloids and reactive solutes during preferential flow and on OM turnover processes in subsoils. The objective was to characterize the mm-to-cm scale spatial distribution of NCOMP and BN+NA at intact macropore surfaces from the Bt-horizons of two Luvisols developed on loess and glacial till. In material manually separated from macropore surfaces the proportions of NCOMP and BN+NA were determined by pyrolysis-field ionization mass spectrometry (Py-FIMS). These OM compounds, likely originating from combustion residues, were found increased in crack coatings and pinhole fillings but decreased in biopore walls (worm burrows and root channels). The Py-FIMS data were correlated with signals from C=O and C=C groups and with signals from O-H groups of clay minerals as determined by Fourier transform infrared spectroscopy in diffuse reflectance mode (DRIFT). Intensive signals of C15 to C17 alkanes from long-chain alkenes as main components of diesel and diesel exhaust particulates substantiated the assumption that burning residues were prominent in the subsoil OM. The spatial distribution of NCOMP and BN+NA along the macropores was predicted by partial least squares regression (PLSR) using DRIFT mapping spectra from intact surfaces and was found closely related to the distribution of crack coatings and pinholes. The results emphasize the importance of clay coatings in the subsoil to OM sorption and stabilization

  6. Installing artificial macropores in degraded soils to enhance vertical infiltration and increase soil carbon content

    NASA Astrophysics Data System (ADS)

    Mori, Yasushi; Fujihara, Atsushi; Yamagishi, Kazuto

    2014-12-01

    Of all terrestrial media (including vegetation and the atmosphere), soil is the largest store of carbon. Soils also have important functions such as water storage and plant support roles. However, at present, these characteristics do not fully function, because of, for example, climate-change-induced heavy rainfall would wash away the organic-rich surface soils. In this study, artificial macropores were introduced into exposed soil plots for the purpose of enhancing infiltration, and fibrous material was inserted to reinforce the macropore structure. As expected, the capillary force caused by the fibers drew surface water deeper into the soil profile before saturation. Additionally, the same capillary force promoted vertical transport, while micropores (matrix) enhanced horizontal flow. Our results show that infiltration was more effective in the fiber-containing macropores than in empty macropores. Additionally, our column experiments showed that artificial macropores reduced surface runoff when the rainfall intensities were 2, 4, and 20 mm · h-1 but not for 80 mm · h-1. In field experiments, soil moisture sensors installed at depths of 10, 30, and 50 cm responded well to rainfall, showing that artificial macropores were able to successfully introduce surface water into the soil profile. One year after the artificial macropores were installed, a field survey carried out to assess soil organic matter and plant growth showed that plant biomass had doubled and that there was a significant increase in soil carbon. This novel technique has many advantages as it mimics natural processes, is low cost, and has a simple structure.

  7. Coupling of Spinosad Fermentation and Separation Process via Two-Step Macroporous Resin Adsorption Method.

    PubMed

    Zhao, Fanglong; Zhang, Chuanbo; Yin, Jing; Shen, Yueqi; Lu, Wenyu

    2015-08-01

    In this paper, a two-step resin adsorption technology was investigated for spinosad production and separation as follows: the first step resin addition into the fermentor at early cultivation period to decrease the timely product concentration in the broth; the second step of resin addition was used after fermentation to adsorb and extract the spinosad. Based on this, a two-step macroporous resin adsorption-membrane separation process for spinosad fermentation, separation, and purification was established. Spinosad concentration in 5-L fermentor increased by 14.45 % after adding 50 g/L macroporous at the beginning of fermentation. The established two-step macroporous resin adsorption-membrane separation process got the 95.43 % purity and 87 % yield for spinosad, which were both higher than that of the conventional crystallization of spinosad from aqueous phase that were 93.23 and 79.15 % separately. The two-step macroporous resin adsorption method has not only carried out the coupling of spinosad fermentation and separation but also increased spinosad productivity. In addition, the two-step macroporous resin adsorption-membrane separation process performs better in spinosad yield and purity.

  8. Photoconductivity of Macroporous and Nonporous Silicon with Ultrathin Oxide Layers

    NASA Astrophysics Data System (ADS)

    Konin, K. P.; Goltvyansky, Yu. V.; Karachevtseva, L. A.; Karas, M. I.; Morozovs'ka, D. V.

    2018-06-01

    The photoconductivity of macroporous silicon with ultrathin oxide layers of 2.7-30 nm in thickness at short-wave optical excitation was studied. The following feature was revealed: a nonmonotonic change in the photoconductivity as a function of the oxide thickness. At a minimum thickness, the photoconductivity is negative; in the interval 6.8-15 nm, it is very much suppressed; at 15-30 nm, it is positive. Suppression of photoconductivity over a wide thickness range indicates an abnormally high concentration of traps and capture centers for charge carriers of both signs. Such a change in the photoconductivity corresponds to the known results on the continuous morphological rearrangement of the oxide in the thickness range from 6-7 nm to 12-15 nm from the coesite-like (4-membered SiO4 tetrahedra rings) to the tridymite-like (6-membered SiO4 tetrahedra rings). The suppression of photoconductivity in the intermediate range probably demonstrates the collective, antisynergetic action of these coexisting oxide forms on the nonequilibrium charge carriers. These coexisting oxide forms manifest themselves as an unusual collective defect.

  9. Bioactive macroporous titanium implants highly interconnected.

    PubMed

    Caparrós, Cristina; Ortiz-Hernandez, Mónica; Molmeneu, Meritxell; Punset, Miguel; Calero, José Antonio; Aparicio, Conrado; Fernández-Fairén, Mariano; Perez, Román; Gil, Francisco Javier

    2016-10-01

    Intervertebral implants should be designed with low load requirements, high friction coefficient and low elastic modulus in order to avoid the stress shielding effect on bone. Furthermore, the presence of a highly interconnected porous structure allows stimulating bone in-growth and enhancing implant-bone fixation. The aim of this study was to obtain bioactive porous titanium implants with highly interconnected pores with a total porosity of approximately 57 %. Porous Titanium implants were produced by powder sintering route using the space holder technique with a binder phase and were then evaluated in an in vivo study. The size of the interconnection diameter between the macropores was about 210 μm in order to guarantee bone in-growth through osteblastic cell penetration. Surface roughness and mechanical properties were analyzed. Stiffness was reduced as a result of the powder sintering technique which allowed the formation of a porous network. Compression and fatigue tests exhibited suitable properties in order to guarantee a proper compromise between mechanical properties and pore interconnectivity. Bioactivity treatment effect in novel sintered porous titanium materials was studied by thermo-chemical treatments and were compared with the same material that had undergone different bioactive treatments. Bioactive thermo-chemical treatment was confirmed by the presence of sodium titanates on the surface of the implants as well as inside the porous network. Raman spectroscopy results suggested that the identified titanate structures would enhance in vivo apatite formation by promoting ion exchange for the apatite formation process. In vivo results demonstrated that the bioactive titanium achieved over 75 % tissue colonization compared to the 40 % value for the untreated titanium.

  10. A Macroporous TiO2 Oxygen Sensor Fabricated Using Anodic Aluminium Oxide as an Etching Mask

    PubMed Central

    Lu, Chih-Cheng; Huang, Yong-Sheng; Huang, Jun-Wei; Chang, Chien-Kuo; Wu, Sheng-Po

    2010-01-01

    An innovative fabrication method to produce a macroporous Si surface by employing an anodic aluminium oxide (AAO) nanopore array layer as an etching template is presented. Combining AAO with a reactive ion etching (RIE) processes, a homogeneous and macroporous silicon surface can be effectively configured by modulating AAO process parameters and alumina film thickness, thus hopefully replacing conventional photolithography and electrochemical etch methods. The hybrid process integration is considered fully CMOS compatible thanks to the low-temperature AAO and CMOS processes. The gas-sensing characteristics of 50 nm TiO2 nanofilms deposited on the macroporous surface are compared with those of conventional plain (or non-porous) nanofilms to verify reduced response noise and improved sensitivity as a result of their macroporosity. Our experimental results reveal that macroporous geometry of the TiO2 chemoresistive gas sensor demonstrates 2-fold higher (∼33%) improved sensitivity than a non-porous sensor at different levels of oxygen exposure. In addition, the macroporous device exhibits excellent discrimination capability and significantly lessened response noise at 500 °C. Experimental results indicate that the hybrid process of such miniature and macroporous devices are compatible as well as applicable to integrated next generation bio-chemical sensors. PMID:22315561

  11. A macroporous TiO2 oxygen sensor fabricated using anodic aluminium oxide as an etching mask.

    PubMed

    Lu, Chih-Cheng; Huang, Yong-Sheng; Huang, Jun-Wei; Chang, Chien-Kuo; Wu, Sheng-Po

    2010-01-01

    An innovative fabrication method to produce a macroporous Si surface by employing an anodic aluminium oxide (AAO) nanopore array layer as an etching template is presented. Combining AAO with a reactive ion etching (RIE) processes, a homogeneous and macroporous silicon surface can be effectively configured by modulating AAO process parameters and alumina film thickness, thus hopefully replacing conventional photolithography and electrochemical etch methods. The hybrid process integration is considered fully CMOS compatible thanks to the low-temperature AAO and CMOS processes. The gas-sensing characteristics of 50 nm TiO(2) nanofilms deposited on the macroporous surface are compared with those of conventional plain (or non-porous) nanofilms to verify reduced response noise and improved sensitivity as a result of their macroporosity. Our experimental results reveal that macroporous geometry of the TiO(2) chemoresistive gas sensor demonstrates 2-fold higher (∼33%) improved sensitivity than a non-porous sensor at different levels of oxygen exposure. In addition, the macroporous device exhibits excellent discrimination capability and significantly lessened response noise at 500 °C. Experimental results indicate that the hybrid process of such miniature and macroporous devices are compatible as well as applicable to integrated next generation bio-chemical sensors.

  12. Investigation of Episodic Flow from Unsaturated Porous Media into a Macropore

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

    R. K. Podgorney; J. P. Fairley

    Th e recent literature contains numerous observations of episodic or intermittent fl ow in unsaturated flow systems under both constant fl ux and ponded boundary conditions. Flow systems composed of a heterogeneous porous media, as well as discrete fracture networks, have been cited as examples of systems that can exhibit episodic fl ow. Episodic outfl ow events are significant because relatively large volumes of water can move rapidly through an unsaturated system, carrying water and contaminants to depth greatly ahead of a wetting front predicted by a one-dimensional, gravity-driven diff usive infiltration model. In this study, we model the behaviormore » of water flow through a sand column underlain by an impermeable-walled macropore. Relative permeability and capillary pressure relationships were developed that capture the complex interrelationships between the macropore and the overlying porous media that control fl ow out of the system. The potential for episodic flow is assessed and compared to results of conventional modeling approaches and experimental data from the literature. Model results using coupled matrix–macropore relative permeability and capillary pressure relationships capture the behavior observed in laboratory experiments remarkably well, while simulations using conventional relative permeability and capillary pressure functions fail to capture some of the observed fl ow dynamics. Capturing the rapid downward movement of water suggests that the matrix-macropore capillary pressure and relative permeability functions developed have the potential to improve descriptions of fl ow and transport processes in heterogeneous, variably saturated media.« less

  13. Homogenization-assisted cavitation hybrid rotation extraction and macroporous resin enrichment of dihydroquercetin from Larix gmelinii.

    PubMed

    Xia, Yu; Wang, Yinhang; Li, Wei; Ma, Chunhui; Liu, Shouxin

    2017-12-01

    Cavitation hybrid rotation, which was and is still looked upon as an unavoidable nuisance in the flow systems, for extraction processing intensification of active chemical compounds from natural products. In this study, a homogenization-assisted cavitation hybrid rotation extraction method was applied to extract dihydroquercetin (DHQ) from larch (Larix gmelinii) wood root. The extraction parameters were optimized in single factor experiments with the DHQ extraction yields as the response values. The optimum conditions were as follows: number of extractions, three; ethanol volume fraction for the extraction, 60%; liquid-solid ratio for homogenization, 10mL/g; homogenization time, 8min; liquid-solid ratio for cavitation extraction, 9mL/g, and cavitation extraction time, 35min. Under these conditions, the DHQ content in extract was 4.50±0.02mg/g, and the extraction efficiency was higher than those of traditional techniques. Cavitation can be effectively used to improve the extraction rate by increasing the mass transfer rates and possible rupture of cell wall due to formation of microcavities leading to higher product yields with reduced processing time and solvent consumption. After the extraction process, macroporous resin column chromatography was used to concentrate and purify the DHQ. Three resins were selected from fifteen macroporous resins for further investigation of their performance. Among these resins, AB-8 resin exhibited relatively better adsorption capacities and desorption ratios for DHQ. The ethanol volume fraction of the solutions for sample loading and desorption, and flow rates for loading and desorption were optimized for the macroporous resin column chromatography. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Direct Writing of Three-Dimensional Macroporous Photonic Crystals on Pressure-Responsive Shape Memory Polymers.

    PubMed

    Fang, Yin; Ni, Yongliang; Leo, Sin-Yen; Wang, Bingchen; Basile, Vito; Taylor, Curtis; Jiang, Peng

    2015-10-28

    Here we report a single-step direct writing technology for making three-dimensional (3D) macroporous photonic crystal patterns on a new type of pressure-responsive shape memory polymer (SMP). This approach integrates two disparate fields that do not typically intersect: the well-established templating nanofabrication and shape memory materials. Periodic arrays of polymer macropores templated from self-assembled colloidal crystals are squeezed into disordered arrays in an unusual shape memory "cold" programming process. The recovery of the original macroporous photonic crystal lattices can be triggered by direct writing at ambient conditions using both macroscopic and nanoscopic tools, like a pencil or a nanoindenter. Interestingly, this shape memory disorder-order transition is reversible and the photonic crystal patterns can be erased and regenerated hundreds of times, promising the making of reconfigurable/rewritable nanooptical devices. Quantitative insights into the shape memory recovery of collapsed macropores induced by the lateral shear stresses in direct writing are gained through fundamental investigations on important process parameters, including the tip material, the critical pressure and writing speed for triggering the recovery of the deformed macropores, and the minimal feature size that can be directly written on the SMP membranes. Besides straightforward applications in photonic crystal devices, these smart mechanochromic SMPs that are sensitive to various mechanical stresses could render important technological applications ranging from chromogenic stress and impact sensors to rewritable high-density optical data storage media.

  15. Site-specificity of abnormal excision: the mechanism of formation of a specialized transducing bacteriophage lambda plac5.

    PubMed Central

    Shpakovski, G V; Berlin, Y A

    1984-01-01

    Molecular mechanism of the specialized transducing bacteriophage lambda plac5 formation has been studied. Phage-bacterial DNA junctions in lambda plac5 DNA are localized and primary structure of regions of the abnormal excisional recombination leading to the phage formation is elucidated; the crossover region proved to be comparable with the central part of attP and attB sites (the core and the adjacent tetranucleotide) in length and degree of homology. Bacterial insert in lambda plac5 DNA is shown to end immediately after Z-Y spacer, the DNA not containing lacY gene segments. The data obtained led to the conclusion of site-specific (homologous) character of abnormal excision upon formation of lambda transducing bacteriophages. Possible mechanisms of the excision are discussed. Images PMID:6091038

  16. Structure, MC3T3-E1 cell response, and osseointegration of macroporous titanium implants covered by a bioactive microarc oxidation coating with microporous structure.

    PubMed

    Zhou, Rui; Wei, Daqing; Cheng, Su; Feng, Wei; Du, Qing; Yang, Haoyue; Li, Baoqiang; Wang, Yaming; Jia, Dechang; Zhou, Yu

    2014-04-09

    Macroporous Ti with macropores of 50-400 μm size is prepared by sintering Ti microbeads with different diameters of 100, 200, 400, and 600 μm. Bioactive microarc oxidation (MAO) coatings with micropores of 2-5 μm size are prepared on the macroporous Ti. The MAO coatings are composed of a few TiO2 nanocrystals and lots of amorphous phases with Si, Ca, Ti, Na, and O elements. Compared to compact Ti, the MC3T3-E1 cell attachment is prolonged on macroporous Ti without and with MAO coatings; however, the cell proliferation number increases. These results are contributed to the effects of the space structure of macroporous Ti and the surface chemical feature and element dissolution of the MAO coatings during the cell culture. Macroporous Ti both without and with MAO coatings does not cause any adverse effects in vivo. The new bone grows well into the macropores and micropores of macroporous Ti with MAO coatings, showing good mechanical properties in vivo compared to Ti, MAO-treated Ti, and macroporous Ti because of its excellent osseointegration. Moreover, the MAO coatings not only show a high interface bonding strength with new bones but also connect well with macroporous Ti. Furthermore, the pushing out force for macroporous Ti with MAO coatings increases significantly with increasing microbead diameter.

  17. Fast plasma sintering delivers functional graded materials components with macroporous structures and osseointegration properties.

    PubMed

    Godoy, R F; Coathup, M J; Blunn, G W; Alves, A L; Robotti, P; Goodship, A E

    2016-04-13

    We explored the osseointegration potential of two macroporous titanium surfaces obtained using fast plasma sintering (FPS): Ti macroporous structures with 400-600 µmØ pores (TiMac400) and 850-1000 µmØ pores (TiMac850). They were compared against two surfaces currently in clinical use: Ti-Growth® and air plasma spray (Ti-Y367). Each surface was tested, once placed over a Ti-alloy and once onto a CoCr bulk substrate. Implants were placed in medial femoral condyles in 24 sheep. Samples were explanted at four and eight weeks after surgery. Push-out loads were measured using a material-testing system. Bone contact and ingrowth were assessed by histomorphometry and SEM and EDX analyses. Histology showed early osseointegration for all the surfaces tested. At 8 weeks, TiMac400, TiMac850 and Ti-Growth® showed deep bone ingrowth and extended colonisation with newly formed bone. The mechanical push-out force was equal in all tested surfaces. Plasma spray surfaces showed greater bone-implant contact and higher level of pores colonisation with new bone than FPS produced surfaces. However, the void pore area in FPS specimens was significantly higher, yet the FPS porous surfaces allowed a deeper osseointegration of bone to implant. FPS manufactured specimens showed similar osseointegration potential to the plasma spray surfaces for orthopaedic implants. FPS is a useful technology for manufacturing macroporous titanium surfaces. Furthermore, its capability to combine two implantable materials, using bulk CoCr with macroporous titanium surfaces, could be of interest as it enables designers to conceive and manufacture innovative components. FPS delivers functional graded materials components with macroporous structures optimised for osseointegration.

  18. In Situ Gold Nanoparticle Gradient Formation in a 3D Meso- and Macroporous Polymer Matrix.

    PubMed

    Penders, Jelle; Rajasekharan, Anand K; Hulander, Mats; Andersson, Martin

    2017-08-01

    Herein, the development and characterization of a 3D gradient structure of gold nanoparticles is described. The gradient of gold nanoparticles is made in situ in a macroporous nonionic block copolymer hydrogel matrix, through gold ion diffusion control. The polymer provides a matrix for diffusion of gold ions, acts as a template for controlling nanoparticle growth, and facilitates the in situ reduction of gold ions to gold nanoparticles. A clear gradient in gold nanoparticles is observed across the 3D space of the polymer matrix using scanning electron microscopy, fluorescence microscopy, atomic force microscopy, and thermogravimetric analysis. The particle gradient is further functionalized with both hydrophobic and hydrophilic groups via thiol-gold linkage to demonstrate the ability to form gradients with different chemical functionalities. Using additive manufacturing, the polymer can also be printed as a porous network with possible applications for 3D cell culturing in, e.g., biomaterials research. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Palladium nanoparticle deposition via precipitation: a new method to functionalize macroporous silicon

    PubMed Central

    Scheen, Gilles; Bassu, Margherita; Douchamps, Antoine; Zhang, Chao; Debliquy, Marc; Francis, Laurent A

    2014-01-01

    We present an original two-step method for the deposition via precipitation of Pd nanoparticles into macroporous silicon. The method consists in immersing a macroporous silicon sample in a PdCl2/DMSO solution and then in annealing the sample at a high temperature. The impact of composition and concentration of the solution and annealing time on the nanoparticle characteristics is investigated. This method is compared to electroless plating, which is a standard method for the deposition of Pd nanoparticles. Scanning electron microscopy and computerized image processing are used to evaluate size, shape, surface density and deposition homogeneity of the Pd nanoparticles on the pore walls. Energy-dispersive x-ray spectroscopy (EDX) and x-ray photoelectron spectroscopy (XPS) analyses are used to evaluate the composition of the deposited nanoparticles. In contrast to electroless plating, the proposed method leads to homogeneously distributed Pd nanoparticles along the macropores depth with a surface density that increases proportionally with the PdCl2 concentration. Moreover EDX and XPS analysis showed that the nanoparticles are composed of Pd in its metallic state, while nanoparticles deposited by electroless plating are composed of both metallic Pd and PdOx. PMID:27877732

  20. Nonenzymatic glucose detection by using a three-dimensionally ordered, macroporous platinum template.

    PubMed

    Song, Yan-Yan; Zhang, Dai; Gao, Wei; Xia, Xing-Hua

    2005-03-18

    A three-dimensionally ordered, macroporous, inverse-opal platinum film was synthesized electrochemically by the inverted colloidal-crystal template technique. The inverse-opal film that contains platinum nanoparticles showed improved electrocatalytic activity toward glucose oxidation with respect to the directly deposited platinum; this improvement is due to the interconnected porous structure and the greatly enhanced effective surface area. In addition, the inverse-opal Pt-film electrode responds more sensitively to glucose than to common interfering species of ascorbic acid, uric acid, and p-acetamidophenol due to their different electrochemical reaction mechanisms. Results showed that the ordered macroporous materials with enhanced selectivity and sensitivity are promising for fabrication of nonenzymatic glucose biosensors.

  1. Synthesis of Macroporous Poly(dimethylsiloxane) Scaffolds for Tissue Engineering Applications

    PubMed Central

    Pedraza, Eileen; Brady, Ann-Christina; Fraker, Christopher A.

    2015-01-01

    Macroporous, biostable scaffolds with controlled porous architecture were prepared from poly(dimethylsiloxane) (PDMS) using sodium chloride particles (NaCl) and a solvent casting and particulate leaching (SCPL) technique. The effect of particulate size range and overall porosity on the resulting structure was evaluated. Results found 90% v/v scaffolds and particulate ranges above 100 µm to have the most optimal open framework and porosity. Resulting hydrophobic PDMS scaffolds were coated with fibronectin and evaluated as a platform for adherent cell culture using human mesenchymal stem cells. Biocompatibility of PDMS scaffolds was also evaluated in a rodent model, where implants were found to be highly biocompatibile and biostable, with positive extracellular matrix deposition throughout the scaffold. These results demonstrate the suitability of macroporous PDMS scaffolds for tissue engineering applications where strong integration with the host is desired. PMID:23683037

  2. Development of gelatin/carboxymethyl chitosan/nano-hydroxyapatite composite 3D macroporous scaffold for bone tissue engineering applications.

    PubMed

    Maji, Somnath; Agarwal, Tarun; Das, Joyjyoti; Maiti, Tapas Kumar

    2018-06-01

    The present study delineates a relatively simpler approach for fabrication of a macroporous three-dimensional scaffold for bone tissue engineering. The novelty of the work is to obtain a scaffold with macroporosity (interconnected networks) through a combined approach of high stirring induced foaming of the gelatin/carboxymethyl chitosan (CMC)/nano-hydroxyapatite (nHAp) matrix followed by freeze drying. The fabricated macroporous (SGC) scaffold had a greater pore size, higher porosity, higher water retention capacity, slow and sustained enzymatic degradation rate along with higher compressive strength compared to that of non-macroporous (NGC, prepared by conventional freeze drying methodology) scaffold. The biological studies revealed the increased percentage of viability, proliferation, and differentiation as well as higher mineralization of differentiated human Wharton's jelly MSC microtissue (wjhMSC-MT) on SGC as compared to NGC scaffold. RT-PCR also showed enhanced expression level of collagen type I, osteocalcin and Runx2 when seeded on SGC. μCT and histological analysis further revealed a penetration of cellular spheroid to a greater depth in SGC scaffold than NGC scaffold. Furthermore, the effect of cryopreservation on microtissue survival on the three-dimensional construct revealed significant higher viability upon revival in macroporous SGC scaffolds. These results together suggest that high stirring based macroporous scaffolds could have a potential application in bone tissue engineering. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. [Investigation on the process of sapindus saponin purified with macroporous adsorption resin and screening of its bacteriostasis].

    PubMed

    Fu, Yong; Lei, Peng; Han, Yu-mei; Yan, Dan

    2010-02-01

    To study the technological parameters of the purification process of saponins with macroporous adsorption resin. The adsorptive characteristics and elutive parameters of the process were studied by taking the elutive and purified ratio of saponins as markers. Bacteriostasis activity of each parts eluted was evaluated by the mean of cup-plate method. 13.6 mL of the extraction of sapindus saponin (crude drugs 0.01 g/mL) was purified with a column of macroporous adsorption resin (phi15 mm x H90 mm, dry weight 2.5 g) and washed with 3BV of distilled water, then eluted with 3BV of 30% ethanol and 3BV of 70% ethanol, most of saponins were collected in the 70% ethanol. With macroporous adsorption resin adsorbing and purifying, the elutive ratio of saponins was 93.8% and the purity reached 250.1%. So this process of applying macroporous adsorption resin to adsorb and purify saponins is feasible, and supplies reference to the purification of other types of saponin.

  4. Effects of expected-value information and display format on recognition of aircraft subsystem abnormalities

    NASA Technical Reports Server (NTRS)

    Palmer, Michael T.; Abbott, Kathy H.

    1994-01-01

    This study identifies improved methods to present system parameter information for detecting abnormal conditions and to identify system status. Two workstation experiments were conducted. The first experiment determined if including expected-value-range information in traditional parameter display formats affected subject performance. The second experiment determined if using a nontraditional parameter display format, which presented relative deviation from expected value, was better than traditional formats with expected-value ranges included. The inclusion of expected-value-range information onto traditional parameter formats was found to have essentially no effect. However, subjective results indicated support for including this information. The nontraditional column deviation parameter display format resulted in significantly fewer errors compared with traditional formats with expected-value-ranges included. In addition, error rates for the column deviation parameter display format remained stable as the scenario complexity increased, whereas error rates for the traditional parameter display formats with expected-value ranges increased. Subjective results also indicated that the subjects preferred this new format and thought that their performance was better with it. The column deviation parameter display format is recommended for display applications that require rapid recognition of out-of-tolerance conditions, especially for a large number of parameters.

  5. Silicon macroporous arrays with high aspect ratio prepared by ICP etching

    NASA Astrophysics Data System (ADS)

    Wang, Guozheng; Yang, Bingchen; Wang, Ji; Yang, Jikai; Duanmu, Qingduo

    2018-02-01

    This paper reports on a macroporous silicon arrays with high aspect ratio, the pores of which are of 162, 205, 252, 276μm depths with 6, 10, 15 and 20 μm diameters respectively, prepared by Multiplex Inductively Coupled Plasma (ICP) etching. It was shown that there are very differences in process of high aspect ratio microstructures between the deep pores, a closed structure, and deep trenches, a open structure. The morphology and the aspect ratio dependent etching were analyzed and discussed. The macroporous silicon etched by ICP process yield an uneven, re-entrant, notched and ripples surface within the pores. The main factors effecting on the RIE lag of HARP etching are the passivation cycle time, the pressure of reactive chamber, and the platen power of ICP system.

  6. Mitochondrial Abnormality Facilitates Cyst Formation in Autosomal Dominant Polycystic Kidney Disease

    PubMed Central

    Ishimoto, Yu; Yoshihara, Daisuke; Kugita, Masanori; Nagao, Shizuko; Shimizu, Akira; Takeda, Norihiko; Wake, Masaki; Honda, Kenjiro; Zhou, Jing

    2017-01-01

    ABSTRACT Autosomal dominant polycystic kidney disease (ADPKD) constitutes the most inherited kidney disease. Mutations in the PKD1 and PKD2 genes, encoding the polycystin 1 and polycystin 2 Ca2+ ion channels, respectively, result in tubular epithelial cell-derived renal cysts. Recent clinical studies demonstrate oxidative stress to be present early in ADPKD. Mitochondria comprise the primary reactive oxygen species source and also their main effector target; however, the pathophysiological role of mitochondria in ADPKD remains uncharacterized. To clarify this function, we examined the mitochondria of cyst-lining cells in ADPKD model mice (Ksp-Cre PKD1flox/flox) and rats (Han:SPRD Cy/+), demonstrating obvious tubular cell morphological abnormalities. Notably, the mitochondrial DNA copy number and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) expression were decreased in ADPKD model animal kidneys, with PGC-1α expression inversely correlated with oxidative stress levels. Consistent with these findings, human ADPKD cyst-derived cells with heterozygous and homozygous PKD1 mutation exhibited morphological and functional abnormalities, including increased mitochondrial superoxide. Furthermore, PGC-1α expression was suppressed by decreased intracellular Ca2+ levels via calcineurin, p38 mitogen-activated protein kinase (MAPK), and nitric oxide synthase deactivation. Moreover, the mitochondrion-specific antioxidant MitoQuinone (MitoQ) reduced intracellular superoxide and inhibited cyst epithelial cell proliferation through extracellular signal-related kinase/MAPK inactivation. Collectively, these results indicate that mitochondrial abnormalities facilitate cyst formation in ADPKD. PMID:28993480

  7. Ionic liquid-regenerated macroporous cellulose monolith: Fabrication, characterization and its protein chromatography.

    PubMed

    Du, Kaifeng

    2017-04-21

    Macroporous cellulose monolith as chromatographic support was successfully fabricated from an ionic liquid dissolved cellulose solution by an emulsification method and followed by the cross-linking reaction and DEAE modification. With the physical characterization, the cellulose monolith featured by both the interconnected macropores in range of 0.5-2.5μm and the diffusion pores centered at about 10nm. Given the bimodal pore system, the monolith possessed the specific surface area of 36.4m 2 g -1 and the column permeability of about 7.45×10 -14 m 2 . After the DEAE modification, the anion cellulose monolith was evaluated for its chromatography performances. It demonstrated that the static and dynamic adsorption capacity of BSA reached about 66.7mgmL -1 and 43.9mgmL -1 at 10% breakthrough point, respectively. The results were comparable to other chromatographic adsorbent. In addition, the proteins mixture with different pI was well separated at high flow velocity (611.0cmh -1 ) and high protein recovery (over 97%), proving the macroporous cellulose monolith had excellent separation performance. In this way, the prepared cellulose monolith with bimodal pores system is expected for the potential application in high-speed chromatography. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Fabrication of macroporous cement scaffolds using PEG particles: In vitro evaluation with induced pluripotent stem cell-derived mesenchymal progenitors.

    PubMed

    Sladkova, Martina; Palmer, Michael; Öhman, Caroline; Alhaddad, Rawan Jaragh; Esmael, Asmaa; Engqvist, Håkan; de Peppo, Giuseppe Maria

    2016-12-01

    Calcium phosphate cements (CPCs) have been extensively used in reconstructive dentistry and orthopedics, but it is only recently that CPCs have been combined with stem cells to engineer biological substitutes with enhanced healing potential. In the present study, macroporous CPC scaffolds with defined composition were fabricated using an easily reproduced synthesis method, with minimal fabrication and processing steps. Scaffold pore size and porosity, essential for cell infiltration and tissue ingrowth, were tuned by varying the content and size of polyethylene glycol (PEG) particles, resulting in 9 groups with different architectural features. The scaffolds were characterized for chemical composition, porosity and mechanical properties, then tested in vitro with human mesenchymal progenitors derived from induced pluripotent stem cells (iPSC-MPs). Biomimetic decellularized bone scaffolds were used as reference material in this study. Our manufacturing process resulted in the formation of macroporous monetite scaffolds with no residual traces of PEG. The size and content of PEG particles was found to affect scaffold porosity, and thus mechanical properties. Irrespective of pore size and porosity, the CPC scaffolds fabricated in this study supported adhesion and viability of human iPSC-MPs similarly to decellularized bone scaffolds. However, the architectural features of the scaffolds were found to affect the expression of bone specific genes, suggesting that specific scaffold groups could be more suitable to direct human iPSC-MPs in vitro toward an osteoblastic phenotype. Our simplistic fabrication method allows rapid, inexpensive and reproducible construction of macroporous CPC scaffolds with tunable architecture for potential use in dental and orthopedic applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Fabrication of magnetic macroporous chitosan-g-poly (acrylic acid) hydrogel for removal of Cd2+ and Pb2.

    PubMed

    Zhu, Yongfeng; Zheng, Yian; Wang, Feng; Wang, Aiqin

    2016-12-01

    A novel macroporous magnetic macroporous chitosan-g-poly (acrylic acid) hydrogel adsorbent was fabricated from the Pickering high internal emulsions template stabilized by modified Fe 3 O 4 nanoparticles. The structure and composition of modified Fe 3 O 4 and macroporous magnetic hydrogel were characterized by TEM, XRD, TG and SEM techniques. The characterization results suggest that the Fe 3 O 4 nanoparticles have been modified successfully with organosilane of 3-aminopropyltrimethoxysilane (APTES), and the porous structure of the macroporous hydrogel can be tuned with the amount of stabilized particles, volume fraction of dispersed phase and the amount of the cosurfactant. Adsorption experiments indicate that the adsorption equilibrium was rapidly reached within 20min and the maximal adsorption capacities were determined to be 308.84mg/g for Cd 2+ and 695.22mg/g for Pb 2+ . After five adsorption-desorption cycles, the adsorbent can retain its high adsorption capacity. The introduction of Fe 3 O 4 is beneficial to the recycle of adsorbent after usage. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. A New Dual-Pore Formation Factor Model: A Percolation Network Study and Comparison to Experimental Data

    NASA Astrophysics Data System (ADS)

    Tang, Y. B.; Li, M.; Bernabe, Y.

    2014-12-01

    We modeled the electrical transport behavior of dual-pore carbonate rocks in this paper. Based on experimental data of a carbonate reservoir in China, we simply considered the low porosity samples equivalent to the matrix (micro-pore system) of the high porosity samples. For modeling the bimodal porous media, we considered that the matrix is homogeneous and interconnected. The connectivity and the pore size distribution of macro-pore system are varied randomly. Both pore systems are supposed to act electrically in parallel, connected at the nodes, where the fluid exchange takes place, an approach previously used by Bauer et al. (2012). Then, the effect of the properties of matrix, the pore size distribution and connectivity of macro-pore system on petrophysical properties of carbonates can be investigated. We simulated electrical current through networks in three-dimensional simple cubic (SC) and body-center cubic (BCC) with different coordination numbers and different pipe radius distributions of macro-pore system. Based on the simulation results, we found that the formation factor obeys a "universal" scaling relationship (i.e. independent of lattice type), 1/F∝eγz, where γ is a function of the normalized standard deviation of the pore radius distribution of macro-pore system and z is the coordination number of macro-pore system. This relationship is different from the classic "universal power law" in percolation theory. A formation factor model was inferred on the basis of the scaling relationship mentioned above and several scale-invariant quantities (such as hydraulic radius rH and throat length l of macro-pore). Several methods were developed to estimate corresponding parameters of the new model with conventional core analyses. It was satisfactorily tested against experimental data, including some published experimental data. Furthermore, the relationship between water saturation and resistivity in dual-pore carbonates was discussed based on the new model.

  11. The Influence of Syndepositional Macropores on the Hydraulic Integrity of Thick Alluvial Clay Aquitards

    NASA Astrophysics Data System (ADS)

    Timms, Wendy A.; Acworth, R. Ian; Crane, Richard A.; Arns, Christoph H.; Arns, Ji-Youn; McGeeney, Dayna E.; Rau, Gabriel C.; Cuthbert, Mark O.

    2018-04-01

    Clay-rich deposits are commonly assumed to be aquitards which act as natural hydraulic barriers due to their low hydraulic connectivity. Postdepositional weathering processes are known to increase the permeability of aquitards in the near surface but not impact on deeper parts of relatively thick formations. However, syndepositional processes affecting the hydraulic properties of aquitards have previously received little attention in the literature. Here, we analyze a 31 m deep sediment core recovered from an inland clay-rich sedimentary sequence using a combination of techniques including particle size distribution and microscopy, centrifuge dye tracer testing and micro X-ray CT imaging. Subaerial deposition of soils within these fine grained alluvial deposits has led to the preservation of considerable macropores (root channels or animal burrows). Connected pores and macropores thus account for vertical hydraulic conductivity (K) of 4.2×10-9 m/s (geometric mean of 13 samples) throughout the thick aquitard, compared to a matrix K that is likely <10-10 m/s, the minimum K value that was measured. Our testing demonstrates that such syndepositional features may compromise the hydraulic integrity of what otherwise appears to have the characteristics of a much lower permeability aquitard. Heterogeneity within a clay-rich matrix could also enhance vertical connectivity, as indicated by digital analysis of pore morphology in CT images. We highlight that the paleo-environment under which the sediment was deposited must be considered when aquitards are investigated as potential natural hydraulic barriers and illustrate the value of combining multiple investigation techniques for characterizing clay-rich deposits.

  12. [Purification Technology Optimization for Saponins from Ziziphi Spinosae Semen with Macroporous Adsorption Resin by Box-Behnken Design-Response Surface Methodology].

    PubMed

    Zhao, Hui-ru; Ren, Zao; Liu, Chun-ye

    2015-04-01

    To compare the purification effect of saponins from Ziziphi Spinosae Semen with different types of macroporous adsorption resin, and to optimize its purification technology. The type of macroporous resins was optimized by static adsorption method. The optimum technological conditions of saponins from Ziziphi Spinosae Semen was screened by single factor test and Box-Behnken Design-Response Surface Methodology. AB-8 macroporous resin had better purification effect of total saponins than other resins, optimum technological parameters were as follows: column height-diameter ratio was 5: 1, the concentration of sample solution was 2. 52 mg/mL, resin adsorption quantity was 8. 915 mg/g, eluted by 3 BV water, flow rate of adsorption and elution was 2 BV/h, elution solvent was 75% ethanol, elution solvent volume was 5 BV. AB-8 macroporous resin has a good purification effect on jujuboside A. The optimized technology is stable and feasible.

  13. Synthesis and properties of immobilized pectinase onto the macroporous polyacrylamide microspheres.

    PubMed

    Lei, Zhongli; Jiang, Qin

    2011-03-23

    Pectinase was covalently immobilized onto the macroporous polyacrylamide (PAM) microspheres synthesized via an inverse suspension polymerization approach, resulting in 81.7% immobilization yield. The stability of the macroporous PAM support, which has a large surface area, is not impeded by the adsorbed proteins despite the fact that up to 296.3 mg of enzyme is immobilized per gram of the carrier particles. The immobilized enzyme retained more than 75% of its initial activity over 30 days, and the optimum temperature/pH also increased to the range of 50-60 °C/3.0-5.0. The immobilized enzyme also exhibited great operational stability, and more than 75% residual activity was observed after 10 batch reactions. The kinetics of a model reaction catalyzed by the immobilized pectinase was finally investigated. Moreover, the immobilized pectinase could be recovered by centrifuging and showed durable activity at the process of recycle.

  14. Current-voltage characteristics in macroporous silicon/SiOx/SnO2:F heterojunctions.

    PubMed

    Garcés, Felipe A; Urteaga, Raul; Acquaroli, Leandro N; Koropecki, Roberto R; Arce, Roberto D

    2012-07-25

    We study the electrical characteristics of macroporous silicon/transparent conductor oxide junctions obtained by the deposition of fluorine doped-SnO2 onto macroporous silicon thin films using the spray pyrolysis technique. Macroporous silicon was prepared by the electrochemical anodization of a silicon wafer to produce pore sizes ranging between 0.9 to 1.2 μm in diameter. Scanning electronic microscopy was performed to confirm the pore filling and surface coverage. The transport of charge carriers through the interface was studied by measuring the current-voltage curves in the dark and under illumination. In the best configuration, we obtain a modest open-circuit voltage of about 70 mV and a short-circuit current of 3.5 mA/cm2 at an illumination of 110 mW/cm2. In order to analyze the effects of the illumination on the electrical properties of the junction, we proposed a model of two opposing diodes, each one associated with an independent current source. We obtain a good accordance between the experimental data and the model. The current-voltage curves in illuminated conditions are well fitted with the same parameters obtained in the dark where only the photocurrent intensities in the diodes are free parameters.

  15. A simple method for the production of large volume 3D macroporous hydrogels for advanced biotechnological, medical and environmental applications

    PubMed Central

    Savina, Irina N.; Ingavle, Ganesh C.; Cundy, Andrew B.; Mikhalovsky, Sergey V.

    2016-01-01

    The development of bulk, three-dimensional (3D), macroporous polymers with high permeability, large surface area and large volume is highly desirable for a range of applications in the biomedical, biotechnological and environmental areas. The experimental techniques currently used are limited to the production of small size and volume cryogel material. In this work we propose a novel, versatile, simple and reproducible method for the synthesis of large volume porous polymer hydrogels by cryogelation. By controlling the freezing process of the reagent/polymer solution, large-scale 3D macroporous gels with wide interconnected pores (up to 200 μm in diameter) and large accessible surface area have been synthesized. For the first time, macroporous gels (of up to 400 ml bulk volume) with controlled porous structure were manufactured, with potential for scale up to much larger gel dimensions. This method can be used for production of novel 3D multi-component macroporous composite materials with a uniform distribution of embedded particles. The proposed method provides better control of freezing conditions and thus overcomes existing drawbacks limiting production of large gel-based devices and matrices. The proposed method could serve as a new design concept for functional 3D macroporous gels and composites preparation for biomedical, biotechnological and environmental applications. PMID:26883390

  16. A simple method for the production of large volume 3D macroporous hydrogels for advanced biotechnological, medical and environmental applications

    NASA Astrophysics Data System (ADS)

    Savina, Irina N.; Ingavle, Ganesh C.; Cundy, Andrew B.; Mikhalovsky, Sergey V.

    2016-02-01

    The development of bulk, three-dimensional (3D), macroporous polymers with high permeability, large surface area and large volume is highly desirable for a range of applications in the biomedical, biotechnological and environmental areas. The experimental techniques currently used are limited to the production of small size and volume cryogel material. In this work we propose a novel, versatile, simple and reproducible method for the synthesis of large volume porous polymer hydrogels by cryogelation. By controlling the freezing process of the reagent/polymer solution, large-scale 3D macroporous gels with wide interconnected pores (up to 200 μm in diameter) and large accessible surface area have been synthesized. For the first time, macroporous gels (of up to 400 ml bulk volume) with controlled porous structure were manufactured, with potential for scale up to much larger gel dimensions. This method can be used for production of novel 3D multi-component macroporous composite materials with a uniform distribution of embedded particles. The proposed method provides better control of freezing conditions and thus overcomes existing drawbacks limiting production of large gel-based devices and matrices. The proposed method could serve as a new design concept for functional 3D macroporous gels and composites preparation for biomedical, biotechnological and environmental applications.

  17. Cystic fibrosis transmembrane regulator gene (CFTR) is associated with abnormal enamel formation.

    PubMed

    Arquitt, C K; Boyd, C; Wright, J T

    2002-07-01

    Cystic fibrosis (CF), a chloride ion transport disorder, is caused by mutations of the cftr gene and is the most common autosomal-recessive heritable disease in Caucasians. CFTR knockout mice have enamel with crystallite defects, retained protein, and hypomineralization, suggesting a role for CFTR in enamel formation and mineralization. This investigation examined CFTR expression and elemental composition in developing murine incisor teeth. RT-PCR showed cftr mRNA expression in the normal mouse apical incisor tissue but not in the CFTR knockout tissue. Elemental analysis by energy-dispersive x-ray spectroscopy showed relatively decreased chloride in secretory-stage CF enamel. Iron and potassium were significantly increased, and calcium was significantly decreased (p value = 0.05) in the CF mature enamel. Abnormal enamel mineralization, ion concentrations, and molecular evidence of cftr mRNA expression by odontogenic cells strongly suggest that CFTR plays an important role in enamel formation.

  18. Abnormal electron-heating mode and formation of secondary-energetic electrons in pulsed microwave-frequency atmospheric microplasmas

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

    Kwon, H. C.; Research and Development Division, SK Hynix Semiconductor Inc., Icheon 467-701; Jung, S. Y.

    2014-03-15

    The formation of secondary energetic electrons induced by an abnormal electron-heating mode in pulsed microwave-frequency atmospheric microplasmas was investigated using particle-in-cell simulation. We found that additional high electron heating only occurs during the first period of the ignition phase after the start of a second pulse at sub-millimeter dimensions. During this period, the electrons are unable to follow the abruptly retreating sheath through diffusion alone. Thus, a self-consistent electric field is induced to drive the electrons toward the electrode. These behaviors result in an abnormal electron-heating mode that produces high-energy electrons at the electrode with energies greater than 50 eV.

  19. Proangiogenic hydrogels within macroporous scaffolds enhance islet engraftment in an extrahepatic site.

    PubMed

    Brady, Ann-Christina; Martino, Mikaël M; Pedraza, Eileen; Sukert, Steve; Pileggi, Antonello; Ricordi, Camillo; Hubbell, Jeffrey A; Stabler, Cherie L

    2013-12-01

    The transplantation of allogeneic islets in recent clinical trials has shown substantial promise as a therapy for type 1 diabetes; however, long-term insulin independence remains inadequate. This has been largely attributed to the current intravascular, hepatic transplant site, which exposes islets to mechanical and inflammatory stresses. A highly macroporous scaffold, housed within an alternative transplant site, can support an ideal environment for islet transplantation by providing three-dimensional distribution of islets, while permitting the infiltration of host vasculature. In the present study, we sought to evaluate the synergistic effect of a proangiogenic hydrogel loaded within the void space of a macroporous poly(dimethylsiloxane) (PDMS) scaffold on islet engraftment. The fibrin-based proangiogenic hydrogel tested presents platelet derived growth factor (PDGF-BB), via a fibronectin (FN) fragment containing growth factor and major integrin binding sites in close proximity. The combination of the proangiogenic hydrogel with PDMS scaffolds resulted in a significant decrease in the time to normoglycemia for syngeneic mouse islet transplants. This benefit was associated with an observed increase in competent vessel branching, as well as mature intraislet vessels. Overall, the addition of the proangiogenic factor PDGF-BB, delivered via the FN fragment-functionalized hydrogel, positively influenced the efficiency of engraftment. These characteristics, along with its ease of retrieval, make this combination of a biostable macroporous scaffold and a degradable proangiogenic hydrogel a supportive structure for insulin-producing cells implanted in extrahepatic sites.

  20. Macroporous resin purification of peptides with umami taste from soy sauce.

    PubMed

    Zhuang, Mingzhu; Zhao, Mouming; Lin, Lianzhu; Dong, Yi; Chen, Huiping; Feng, Mengying; Sun-Waterhouse, Dongxiao; Su, Guowan

    2016-01-01

    In this study, the performance and separation characteristics of four macroporous resins for purifying umami peptides from soy sauce were examined. Results showed that the resins could separate the peptides of soy sauce, and the particle diffusion kinetics model was suitable for describing the whole exothermic (ΔH < 43 kJ/mol) adsorption process on the SP-825 and HP-20 resins, while the pseudo-second-order kinetics model accurately described the XAD-16 and HP-2 MGL resins. Furthermore, the adsorption processes of the peptides followed the Freundlich model. The XAD-16 resin was the most effective resin for the enrichment of peptides due to its high adsorption and total desorption capacities. Interestingly, the umami peptides were enriched in the deionized water fraction. This study provides new insights into exploring performance and separation characteristics of macroporous resins on soy sauce, and indicated that peptide may be the contributor to the umami taste in Chinese soy sauce. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Preparation of monodispersed macroporous core-shell molecularly imprinted particles and their application in the determination of 2,4-dichlorophenoxyacetic acid.

    PubMed

    Liu, Yongliang; He, Yonghuan; Jin, Yulong; Huang, Yanyan; Liu, Guoquan; Zhao, Rui

    2014-01-03

    Porous polymers have aroused extensive attention due to their controllable porous structure in favor of mass transfer and binding capacity. In this work, the novel macroporous core-shell molecularly imprinted polymers (MIP) for selective recognition of 2,4-dichlorophenoxyacetic acid (2,4-D) were prepared by surface initiated atom transfer radical polymerization (si-ATRP). By using one-step swelling and polymerization method, the monodispersed macroporous poly(glycidyl methacrylate) (PGMA) particles were synthesized and used as supporting matrix for preparing surface MIP particles (PGMA@MIP). Thanks to the inner and outer surface-located binding cavities and the macroporous structure, the PGMA@MIPs revealed desirable efficiency for template removal and mass transfer, and thus excellent accessibility and affinity toward template 2,4-D. Moreover, PGMA@MIPs exhibited much higher selectivity toward 2,4-D than PGMA@NIPs. PGMA@MIP particles were directly used to selectively enrich 2,4-D from tap water and the recoveries of 2,4-D were obtained as 90.0-93.4% with relative standard division of 3.1-3.4% (n=3). The macroporous PGMA@MIPs also possessed steady and excellent reusable performance for 2,4-D in four extraction/stripping cycles. This novel macroporous core-shell imprinted material may become a powerful tool for rapid and efficient enrichment and separation of target compounds from the complicated samples. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Macroporous 'bubble' graphene film via template-directed ordered-assembly for high rate supercapacitors.

    PubMed

    Chen, Cheng-Meng; Zhang, Qiang; Huang, Chun-Hsien; Zhao, Xiao-Chen; Zhang, Bing-Sen; Kong, Qing-Qiang; Wang, Mao-Zhang; Yang, Yong-Gang; Cai, Rong; Sheng Su, Dang

    2012-07-21

    A three-dimensional bubble graphene film, with controllable and uniform macropores and tailorable microstructure, was fabricated by a facile hard templating strategy and exhibit extraordinary electrochemical capacitance with high rate capability (1.0 V s(-1)).

  3. Tcof1/Treacle is required for neural crest cell formation and proliferation deficiencies that cause craniofacial abnormalities

    PubMed Central

    Dixon, Jill; Jones, Natalie C.; Sandell, Lisa L.; Jayasinghe, Sachintha M.; Crane, Jennifer; Rey, Jean-Philippe; Dixon, Michael J.; Trainor, Paul A.

    2006-01-01

    Neural crest cells are a migratory cell population that give rise to the majority of the cartilage, bone, connective tissue, and sensory ganglia in the head. Abnormalities in the formation, proliferation, migration, and differentiation phases of the neural crest cell life cycle can lead to craniofacial malformations, which constitute one-third of all congenital birth defects. Treacher Collins syndrome (TCS) is characterized by hypoplasia of the facial bones, cleft palate, and middle and external ear defects. Although TCS results from autosomal dominant mutations of the gene TCOF1, the mechanistic origins of the abnormalities observed in this condition are unknown, and the function of Treacle, the protein encoded by TCOF1, remains poorly understood. To investigate the developmental basis of TCS we generated a mouse model through germ-line mutation of Tcof1. Haploinsufficiency of Tcof1 leads to a deficiency in migrating neural crest cells, which results in severe craniofacial malformations. We demonstrate that Tcof1/Treacle is required cell-autonomously for the formation and proliferation of neural crest cells. Tcof1/Treacle regulates proliferation by controlling the production of mature ribosomes. Therefore, Tcof1/Treacle is a unique spatiotemporal regulator of ribosome biogenesis, a deficiency that disrupts neural crest cell formation and proliferation, causing the hypoplasia characteristic of TCS craniofacial anomalies. PMID:16938878

  4. Tcof1/Treacle is required for neural crest cell formation and proliferation deficiencies that cause craniofacial abnormalities.

    PubMed

    Dixon, Jill; Jones, Natalie C; Sandell, Lisa L; Jayasinghe, Sachintha M; Crane, Jennifer; Rey, Jean-Philippe; Dixon, Michael J; Trainor, Paul A

    2006-09-05

    Neural crest cells are a migratory cell population that give rise to the majority of the cartilage, bone, connective tissue, and sensory ganglia in the head. Abnormalities in the formation, proliferation, migration, and differentiation phases of the neural crest cell life cycle can lead to craniofacial malformations, which constitute one-third of all congenital birth defects. Treacher Collins syndrome (TCS) is characterized by hypoplasia of the facial bones, cleft palate, and middle and external ear defects. Although TCS results from autosomal dominant mutations of the gene TCOF1, the mechanistic origins of the abnormalities observed in this condition are unknown, and the function of Treacle, the protein encoded by TCOF1, remains poorly understood. To investigate the developmental basis of TCS we generated a mouse model through germ-line mutation of Tcof1. Haploinsufficiency of Tcof1 leads to a deficiency in migrating neural crest cells, which results in severe craniofacial malformations. We demonstrate that Tcof1/Treacle is required cell-autonomously for the formation and proliferation of neural crest cells. Tcof1/Treacle regulates proliferation by controlling the production of mature ribosomes. Therefore, Tcof1/Treacle is a unique spatiotemporal regulator of ribosome biogenesis, a deficiency that disrupts neural crest cell formation and proliferation, causing the hypoplasia characteristic of TCS craniofacial anomalies.

  5. Scalable synthesis of hierarchical macropore-rich activated carbon microspheres assembled by carbon nanoparticles for high rate performance supercapacitors

    NASA Astrophysics Data System (ADS)

    Zhang, Dongdong; Zhao, Jianghong; Feng, Chong; Zhao, Rijie; Sun, Yahui; Guan, Taotao; Han, Baixin; Tang, Nan; Wang, Jianlong; Li, Kaixi; Qiao, Jinli; Zhang, Jiujun

    2017-02-01

    A scalable inverse-microemulsion-polymerization-phase-separation coupling method is applied to successfully prepare hierarchical macropore-rich activated carbon microspheres (ACS) using a phenolic resin (PR) precursor followed by carbonization and KOH activation for the first time. The formed ACS materials are assembled by carbon nanoparticles (CNPs). The macropores interspersed among the component CNPs are formed after removing the non-reactive solvent phase in the course of the polymerization of the reactive PR phase, which occupies ∼64% of the total pore volume (∼2.779 cm3 g-1) of the optimized ACS. In combination with mesopores (∼18% of the total pore volume), the ACS possesses meso/macropores approaching 82% of the total pore volume. Micropores are created in the component CNPs via KOH activation, showing shortened ion transport distances in the nanoscale dimension. Both the hierarchical micro/meso/macroporous structure and the inner nanoparticle morphology (short ion diffusion pathways) can significantly contribute to the rapid transport of electrolyte ions throughout the carbonaceous matrix, resulting in superior rate performance of ACS-based supercapacitors. More importantly, the energy densities of the ACS supercapacitors operating in both aqueous and organic electrolyte retain steady over a wide range of power densities varying dramatically from 0.25 to 14.5 kW kg-1 and to 7.0 kW kg-1, respectively.

  6. Bioinspired Mechano‐Sensitive Macroporous Ceramic Sponge for Logical Drug and Cell Delivery

    PubMed Central

    Xu, Changlu; Wei, Zhihao; Gao, Huajian; Bai, Yanjie; Liu, Huiling; Yang, Huilin

    2017-01-01

    On‐demand, ultrahigh precision delivery of molecules and cells assisted by scaffold is a pivotal theme in the field of controlled release, but it remains extremely challenging for ceramic‐based macroporous scaffolds that are prevalently used in regenerative medicine. Sea sponges (Phylum Porifera), whose bodies possess hierarchical pores or channels and organic/inorganic composite structures, can delicately control water intake/circulation and therefore achieve high precision mass transportation of food, oxygen, and wastes. Inspired by leuconoid sponge, in this study, the authors design and fabricate a biomimetic macroporous ceramic composite sponge (CCS) for high precision logic delivery of molecules and cells regulated by mechanical stimulus. The CCS reveals unique on‐demand AND logic release behaviors in response to dual‐gates of moisture and pressure (or strain) and, more importantly, 1 cm3 volume of CCS achieves unprecedentedly delivery precision of ≈100 ng per cycle for hydrophobic or hydrophilic molecules and ≈1400 cells per cycle for fibroblasts, respectively. PMID:28638781

  7. Macroporous polyacrylamide monolithic gels with immobilized metal affinity ligands: the effect of porous structure and ligand coupling chemistry on protein binding.

    PubMed

    Plieva, Fatima; Bober, Beata; Dainiak, Maria; Galaev, Igor Yu; Mattiasson, Bo

    2006-01-01

    Macroporous polyacrylamide gels (MPAAG) with iminodiacetic acid (IDA) functionality were prepared by (i) chemical modification of polyacrylamide gel, (ii) co-polymerization of acrylamide with allyl glycidyl ether (AGE) and N,N'metylene-bis(acrylamide) (MBAAm) followed by coupling IDA ligand or (iii) by copolymerization of acrylamide and MBAAm with functional monomer carrying IDA-functionality (1-(N,N-bis(carboxymethyl)amino-3-allylglycerol). Screening for optimized conditions for the production of the MPAAG with required porous properties was performed in a 96-well chromatographic format that allowed parallel production and analysis of the MPAAG prepared from reaction mixtures with different compositions. Scanning electron microscopy of the fabricated MPAAG revealed two different types of the porous structures: monomodal macroporous structure with large interconnected pores separated by dense non-porous pore walls in case of plain gels or gels produced via copolymerization with AGE. The other type of the MPAAG (gel produced via co-polymerization with functional monomer carrying IDA-functionality) had bimodal pore structure with large interconnected pores separated by the pore walls pierced through with micropores. The effect of different modifications of MPAAG monoliths and of porous structure of the MPAAG (monomodal and bimodal porous structure) on protein binding has been evaluated. Copyright 2006 John Wiley & Sons, Ltd.

  8. Optimization of macropore evolution towards high photocatalytic activity enhancement in meso/macro porous Anatase TiO2

    NASA Astrophysics Data System (ADS)

    Nair, Radhika V.; Gayathri, P. K.; Siva Gummaluri, Venkata; Vijayan, C.

    2017-01-01

    We report on an optimization strategy for macro pore evolution leading to the design of highly photocatalytic 3D hierarchical meso/macroporous TiO2 via much simpler, faster and cost effective synthesis scheme. Meso/macro porous TiO2 is an excellent candidate material for photocatalytic applications owing to the availability of internal surfaces as active sites for redox reactions. The current research scenario focuses on the design of highly efficient photocatalytic systems as well as rapid, facile and cost effective methods of synthesis and optimization of parameters. The present report is on the gradual evolution of macropores in anatase TiO2 by the effective control of pH of the solvent, reaction time, temperature, solvent ratio and reactant concentration via a facile hydrothermal method in this regard. 3D hierarchical macroporous structures are obtained at pH 7 within a comparatively short reaction time of 5 h and demonstrated to be highly photocatalytic (with rate constant four times that of P25 nanoparticles) through photodegradation of Rhodamine B dye.

  9. Sol-gel (template) synthesis of macroporous Mo-based catalysts for hydrothermal oxidation of radionuclide-organic complexes

    NASA Astrophysics Data System (ADS)

    Papynov, E. K.; Palamarchuk, M. S.; Mayorov, V. Yu; Modin, E. B.; Portnyagin, A. S.; Sokol'nitskaya, T. A.; Belov, A. A.; Tananaev, I. G.; Avramenko, V. A.

    2017-07-01

    Molybdenum compounds are industrially demanding as heterogeneous catalysts for oxidation of various organic substances. Highly porous structure of molybdenum-containing catalysts avoids surface's colmatation and prevents blocking catalytic sites that makes these materials play a key role in processes of hydrothermal oxidation of radionuclide organic complexes. The study presents an original way of sol-gel synthesis of new macroporous molybdenum compounds using ;core-shell; colloid template (polymer latex) as poreforming agent. We have described three individual routs of template removal via thermal decomposition to obtain porous materials based on molybdenum compounds. Thermal treatment conditions (temperature, gaseous atmosphere) have been studied with respect to their influence on composition, structure and catalytic properties of synthesized molybdenum systems. The optimal way to synthesis of crystal molybdenum (VI) oxide with ordered porous structure (mean pore size 100-160 nm) has been suggested. Catalytic properties of macroporous molybdenum materials have been investigated in the process of liquid phase and hydrothermal oxidation of such organic substances thiazine and stable Co-EDTA complex. It was shown that macroporous molybdenum oxides could be applied as prospective catalysts for hydrothermal oxidation of organic radionuclide complexes during the processing of radioactive waste.

  10. Facile Synthesis of Radial-Like Macroporous Superparamagnetic Chitosan Spheres with In-Situ Co-Precipitation and Gelation of Ferro-Gels

    PubMed Central

    Yang, Chih-Hui; Wang, Chih-Yu; Huang, Keng-Shiang; Yeh, Chen-Sheng; Wang, Andrew H. -J.; Wang, Wei-Ting; Lin, Ming-Yu

    2012-01-01

    Macroporous chitosan spheres encapsulating superparamagnetic iron oxide nanoparticles were synthesized by a facile and effective one-step fabrication process. Ferro-gels containing ferrous cations, ferric cations and chitosan were dropped into a sodium hydroxide solution through a syringe pump. In addition, a sodium hydroxide solution was employed for both gelation (chitosan) and co-precipitation (ferrous cations and ferric cations) of the ferro-gels. The results showed that the in-situ co-precipitation of ferro-ions gave rise to a radial morphology with non-spheroid macro pores (large cavities) inside the chitosan spheres. The particle size of iron oxide can be adjusted from 2.5 nm to 5.4 nm by tuning the concentration of the sodium hydroxide solution. Using Fourier Transform Infrared Spectroscopy and X-ray diffraction spectra, the synthesized nanoparticles were illustrated as Fe3O4 nanoparticles. In addition, the prepared macroporous chitosan spheres presented a super-paramagnetic behaviour at room temperature with a saturation magnetization value as high as ca. 18 emu/g. The cytotoxicity was estimated using cell viability by incubating doses (0∼1000 µg/mL) of the macroporous chitosan spheres. The result showed good viability (above 80%) with alginate chitosan particles below 1000 µg/mL, indicating that macroporous chitosan spheres were potentially useful for biomedical applications in the future. PMID:23226207

  11. Agarose template for the fabrication of macroporous metal oxide structures.

    PubMed

    Zhou, Jingfang; Zhou, Meifang; Caruso, Rachel A

    2006-03-28

    Agarose gels have been applied as templates for the formation of macroporous metal oxide structures. The preparation of the agarose template is extremely simple, and with variation of the agarose content, control over morphology is demonstrated: The average pore size decreases from 180 to 55 nm and the surface area increases from 238 to 271 m2 g(-1) with increasing agarose content in the gel. The gelling temperature was also found to influence the final template morphology. Conducting sol-gel chemistry within the template structure followed by removal of the template by heating to 450 degrees C gives porous inorganic oxides. The technique has been demonstrated for the oxides of titanium, zirconium, niobium, and tin. The final morphology of the metal oxide is homogeneous and results from a coating of the agarose structure. The pore diameter decreased and the specific surface area of the titanium dioxide materials increased from 28 to 66 m2 g(-1) as the agarose content in the template is increased from 0.5 to 5.0 wt%. The overall pore size and surface area are lower than the original gel due to shrinkage occurring with the sol-gel process, as well as crystallization and a loss of microporosity in the final material.

  12. Uneven biofilm and current distribution in three-dimensional macroporous anodes of bio-electrochemical systems composed of graphite electrode arrays.

    PubMed

    Li, Jun; Hu, Linbin; Zhang, Liang; Ye, Ding-Ding; Zhu, Xun; Liao, Qiang

    2017-03-01

    A 3-D macroporous anode was constructed using different numbers of graphite rod arrays in fixed-volume bio-electrochemical systems (BESs), and the current and biofilm distribution were investigated by dividing the 3-D anode into several subunits. In the fixed-volume chamber, current production was not significantly improved after the electrode number increased to 36. In the case of 100 electrodes, a significant uneven current distribution was found in the macroporous anode. This was attributed to a differential pH distribution, which resulted from proton accumulation inside the macroporous anode. The pH distribution influenced the biofilm development and led to an uneven biofilm distribution. With respect to current generation, the uneven distribution of both the pH and biofilm contributed to the uneven current distribution. The center had a low pH, which led to less biofilm and a lower contribution to the total current, limiting the performance of the BESs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Melanin or a Melanin-Like Substance Interacts with the N-Terminal Portion of Prion Protein and Inhibits Abnormal Prion Protein Formation in Prion-Infected Cells

    PubMed Central

    Hamanaka, Taichi; Nishizawa, Keiko; Sakasegawa, Yuji; Oguma, Ayumi; Teruya, Kenta; Kurahashi, Hiroshi; Hara, Hideyuki; Sakaguchi, Suehiro

    2017-01-01

    ABSTRACT Prion diseases are progressive fatal neurodegenerative illnesses caused by the accumulation of transmissible abnormal prion protein (PrP). To find treatments for prion diseases, we searched for substances from natural resources that inhibit abnormal PrP formation in prion-infected cells. We found that high-molecular-weight components from insect cuticle extracts reduced abnormal PrP levels. The chemical nature of these components was consistent with that of melanin. In fact, synthetic melanin produced from tyrosine or 3-hydroxy-l-tyrosine inhibited abnormal PrP formation. Melanin did not modify cellular or cell surface PrP levels, nor did it modify lipid raft or cellular cholesterol levels. Neither did it enhance autophagy or lysosomal function. Melanin was capable of interacting with PrP at two N-terminal domains. Specifically, it strongly interacted with the PrP region of amino acids 23 to 50 including a positively charged amino acid cluster and weakly interacted with the PrP octarepeat peptide region of residues 51 to 90. However, the in vitro and in vivo data were inconsistent with those of prion-infected cells. Abnormal PrP formation in protein misfolding cyclic amplification was not inhibited by melanin. Survival after prion infection was not significantly altered in albino mice or exogenously melanin-injected mice compared with that of control mice. These data suggest that melanin, a main determinant of skin color, is not likely to modify prion disease pathogenesis, even though racial differences in the incidence of human prion diseases have been reported. Thus, the findings identify an interaction between melanin and the N terminus of PrP, but the pathophysiological roles of the PrP-melanin interaction remain unclear. IMPORTANCE The N-terminal region of PrP is reportedly important for neuroprotection, neurotoxicity, and abnormal PrP formation, as this region is bound by many factors, such as metal ions, lipids, nucleic acids, antiprion compounds

  14. Hierarchical bioceramic scaffolds with 3D-plotted macropores and mussel-inspired surface nanolayers for stimulating osteogenesis

    NASA Astrophysics Data System (ADS)

    Xu, Mengchi; Zhai, Dong; Xia, Lunguo; Li, Hong; Chen, Shiyi; Fang, Bing; Chang, Jiang; Wu, Chengtie

    2016-07-01

    The hierarchical structure of biomaterials plays an important role in the process of tissue reconstruction and regeneration. 3D-plotted scaffolds have been widely used for bone tissue engineering due to their controlled macropore structure and mechanical properties. However, the lack of micro- or nano-structures on the strut surface of 3D-plotted scaffolds, especially for bioceramic scaffolds, limits their biological activity. Inspired by the adhesive versatility of mussels and the active ion-chelating capacity of polydopamine, we set out to prepare a hierarchical bioceramic scaffold with controlled macropores and mussel-inspired surface nanolayers by combining the 3D-plotting technique with the polydopamine/apatite hybrid strategy in order to synergistically accelerate the osteogenesis and angiogenesis. β-Tricalcium phosphate (TCP) scaffolds were firstly 3D-plotted and then treated in dopamine-Tris/HCl and dopamine-SBF solutions to obtain TCP-DOPA-Tris and TCP-DOPA-SBF scaffolds, respectively. It was found that polydopamine/apatite hybrid nanolayers were formed on the surface of both TCP-DOPA-Tris and TCP-DOPA-SBF scaffolds and TCP-DOPA-SBF scaffolds induced apatite mineralization for the second time during the cell culture. As compared to TCP scaffolds, both TCP-DOPA-Tris and TCP-DOPA-SBF scaffolds significantly promoted the osteogenesis of bone marrow stromal cells (BMSCs) as well as the angiogenesis of human umbilical vein endothelial cells (HUVECs), and the TCP-DOPA-SBF group presented the highest in vitro osteogenic/angiogenic activity among the three groups. Furthermore, both TCP-DOPA-Tris and TCP-DOPA-SBF scaffolds significantly improved the formation of new bone in vivo as compared to TCP scaffolds without a nanostructured surface. Our results suggest that the utilization of a mussel-inspired Ca, P-chelated polydopamine nanolayer on 3D-plotted bioceramic scaffolds is a viable and effective strategy to construct a hierarchical structure for synergistically

  15. Formation mechanism of 3D macroporous graphene aerogel in alcohol-water media under gamma-ray radiation

    NASA Astrophysics Data System (ADS)

    Wang, Weikang; Wu, Yihu; Jiang, Zhiwen; Wang, Mozhen; Wu, Qichao; Zhou, Xiao; Ge, Xuewu

    2018-01-01

    The subtle control on the self-assembly behavior of graphene oxide (GO) nanosheets is one of effective ways for the preparation of high-performance macroscopic graphene-based materials. In this work, detailed characterizations and discussion on the morphological and compositional changes on the solid products in various alcohol-water dispersions of GO under γ-ray radiation were carried out, proving the concurrent hydroxyalkylation and reduction processes of GO nanosheets in the system, which triggered the spontaneous self-assembly of the hydroxyalkylated and reduced GO nanosheets (HA-rGO). The pH and the volume ratio of alcohol to water (ϕa/w) are the key factors to control the self-assembly of the HA-rGO sheets. A free-standing graphene hydrogel (GH) only forms in the strong acid alcohol-water media with an appropriate ϕa/w. After the freeze-drying of the GH, a macroporous graphene aerogel (GA) was obtained, which exhibited a high absorption performance for not only nonpolar molecules (cyclohexane and kerosene), but also most polar molecules (toluene, chloroform, glycol, etc). This work demonstrates a comprehensive self-assembly mechanism of GO nanosheets in an aqueous media under γ-ray radiation and reveals that GA produced from the reduction of GO can be used as potential super-adsorbents for not only waste oil, but also the polar alcohols.

  16. Preparation of Macroporous Epitaxial Quartz Films on Silicon by Chemical Solution Deposition.

    PubMed

    Carretero-Genevrier, Adrián; Gich, Martí

    2015-12-21

    This work describes the detailed protocol for preparing piezoelectric macroporous epitaxial quartz films on silicon(100) substrates. This is a three-step process based on the preparation of a sol in a one-pot synthesis which is followed by the deposition of a gel film on Si(100) substrates by evaporation induced self-assembly using the dip-coating technique and ends with a thermal treatment of the material to induce the gel crystallization and the growth of the quartz film. The formation of a silica gel is based on the reaction of a tetraethyl orthosilicate and water, catalyzed by HCl, in ethanol. However, the solution contains two additional components that are essential for preparing mesoporous epitaxial quartz films from these silica gels dip-coated on Si. Alkaline earth ions, like Sr(2+) act as glass melting agents that facilitate the crystallization of silica and in combination with cetyl trimethylammonium bromide (CTAB) amphiphilic template form a phase separation responsible of the macroporosity of the films. The good matching between the quartz and silicon cell parameters is also essential in the stabilization of quartz over other SiO2 polymorphs and is at the origin of the epitaxial growth.

  17. Preparation of Macroporous Epitaxial Quartz Films on Silicon by Chemical Solution Deposition

    PubMed Central

    Carretero-Genevrier, Adrián; Gich, Martí

    2015-01-01

    This work describes the detailed protocol for preparing piezoelectric macroporous epitaxial quartz films on silicon(100) substrates. This is a three-step process based on the preparation of a sol in a one-pot synthesis which is followed by the deposition of a gel film on Si(100) substrates by evaporation induced self-assembly using the dip-coating technique and ends with a thermal treatment of the material to induce the gel crystallization and the growth of the quartz film. The formation of a silica gel is based on the reaction of a tetraethyl orthosilicate and water, catalyzed by HCl, in ethanol. However, the solution contains two additional components that are essential for preparing mesoporous epitaxial quartz films from these silica gels dip-coated on Si. Alkaline earth ions, like Sr2+ act as glass melting agents that facilitate the crystallization of silica and in combination with cetyl trimethylammonium bromide (CTAB) amphiphilic template form a phase separation responsible of the macroporosity of the films. The good matching between the quartz and silicon cell parameters is also essential in the stabilization of quartz over other SiO2 polymorphs and is at the origin of the epitaxial growth. PMID:26710210

  18. Melanin or a Melanin-Like Substance Interacts with the N-Terminal Portion of Prion Protein and Inhibits Abnormal Prion Protein Formation in Prion-Infected Cells.

    PubMed

    Hamanaka, Taichi; Nishizawa, Keiko; Sakasegawa, Yuji; Oguma, Ayumi; Teruya, Kenta; Kurahashi, Hiroshi; Hara, Hideyuki; Sakaguchi, Suehiro; Doh-Ura, Katsumi

    2017-03-15

    Prion diseases are progressive fatal neurodegenerative illnesses caused by the accumulation of transmissible abnormal prion protein (PrP). To find treatments for prion diseases, we searched for substances from natural resources that inhibit abnormal PrP formation in prion-infected cells. We found that high-molecular-weight components from insect cuticle extracts reduced abnormal PrP levels. The chemical nature of these components was consistent with that of melanin. In fact, synthetic melanin produced from tyrosine or 3-hydroxy-l-tyrosine inhibited abnormal PrP formation. Melanin did not modify cellular or cell surface PrP levels, nor did it modify lipid raft or cellular cholesterol levels. Neither did it enhance autophagy or lysosomal function. Melanin was capable of interacting with PrP at two N-terminal domains. Specifically, it strongly interacted with the PrP region of amino acids 23 to 50 including a positively charged amino acid cluster and weakly interacted with the PrP octarepeat peptide region of residues 51 to 90. However, the in vitro and in vivo data were inconsistent with those of prion-infected cells. Abnormal PrP formation in protein misfolding cyclic amplification was not inhibited by melanin. Survival after prion infection was not significantly altered in albino mice or exogenously melanin-injected mice compared with that of control mice. These data suggest that melanin, a main determinant of skin color, is not likely to modify prion disease pathogenesis, even though racial differences in the incidence of human prion diseases have been reported. Thus, the findings identify an interaction between melanin and the N terminus of PrP, but the pathophysiological roles of the PrP-melanin interaction remain unclear. IMPORTANCE The N-terminal region of PrP is reportedly important for neuroprotection, neurotoxicity, and abnormal PrP formation, as this region is bound by many factors, such as metal ions, lipids, nucleic acids, antiprion compounds, and

  19. Multifunctional three-dimensional macroporous nanoelectronic networks for smart materials.

    PubMed

    Liu, Jia; Xie, Chong; Dai, Xiaochuan; Jin, Lihua; Zhou, Wei; Lieber, Charles M

    2013-04-23

    Seamless and minimally invasive integration of 3D electronic circuitry within host materials could enable the development of materials systems that are self-monitoring and allow for communication with external environments. Here, we report a general strategy for preparing ordered 3D interconnected and addressable macroporous nanoelectronic networks from ordered 2D nanowire nanoelectronic precursors, which are fabricated by conventional lithography. The 3D networks have porosities larger than 99%, contain approximately hundreds of addressable nanowire devices, and have feature sizes from the 10-μm scale (for electrical and structural interconnections) to the 10-nm scale (for device elements). The macroporous nanoelectronic networks were merged with organic gels and polymers to form hybrid materials in which the basic physical and chemical properties of the host were not substantially altered, and electrical measurements further showed a >90% yield of active devices in the hybrid materials. The positions of the nanowire devices were located within 3D hybrid materials with ∼14-nm resolution through simultaneous nanowire device photocurrent/confocal microscopy imaging measurements. In addition, we explored functional properties of these hybrid materials, including (i) mapping time-dependent pH changes throughout a nanowire network/agarose gel sample during external solution pH changes, and (ii) characterizing the strain field in a hybrid nanoelectronic elastomer structures subject to uniaxial and bending forces. The seamless incorporation of active nanoelectronic networks within 3D materials reveals a powerful approach to smart materials in which the capabilities of multifunctional nanoelectronics allow for active monitoring and control of host systems.

  20. Macroporous Inverse Opal-like MoxC with Incorporated Mo Vacancies for Significantly Enhanced Hydrogen Evolution.

    PubMed

    Li, Feng; Zhao, Xianglong; Mahmood, Javeed; Okyay, Mahmut Sait; Jung, Sun-Min; Ahmad, Ishfaq; Kim, Seok-Jin; Han, Gao-Feng; Park, Noejung; Baek, Jong-Beom

    2017-07-25

    The hydrogen evolution reaction (HER) is one of the most important pathways for producing pure and clean hydrogen. Although platinum (Pt) is the most efficient HER electrocatalyst, its practical application is significantly hindered by high-cost and scarcity. In this work, an Mo x C with incorporated Mo vacancies and macroporous inverse opal-like (IOL) structure (Mo x C-IOL) was synthesized and studied as a low-cost efficient HER electrocatalyst. The macroporous IOL structure was controllably fabricated using a facile-hard template strategy. As a result of the combined benefits of the Mo vacancies and structural advantages, including appropriate hydrogen binding energy, large exposed surface, robust IOL structure and fast mass/charge transport, the synthesized Mo x C-IOL exhibited significantly enhanced HER electrocatalytic performance with good stability, with performance comparable or superior to Pt wire in both acidic and alkaline solutions.

  1. Preparative separation and purification of steroidal saponins in Paris polyphylla var. yunnanensis by macroporous adsorption resins.

    PubMed

    Liu, Zhen; Wang, Jieyin; Gao, Wenyuan; Man, Shuli; Wang, Ying; Liu, Changxiao

    2013-07-01

    Saponins are active compounds in natural products. Many researchers have tried to find the method for knowing their concentration in herbs. Some methods, such as solid-liquid extraction and solvent extraction, have been developed. However, the extraction methods of the steroidal saponins from Paris polyphylla Smith var. yunnanensis (Liliaceae) are not fully researched. To establish a simple extraction method for the separation of steroidal saponins from the rhizomes of P. polyphylla Smith var. yunnanensis. Macroporous adsorption resins were used for the separation of steroidal saponins. To select the most suitable resins, seven kinds of macroporous resins were selected in this study. The static adsorption and desorption tests on macroporous resins were determined. Also, we optimized the temperature and the ethanol concentration in the extraction method by the contents of five kinds of saponins. Then, we compared the extraction method with two other methods. D101 resin demonstrated the best adsorption and desorption properties for steroidal saponins. Its adsorption data fits best to the Freundlich adsorption model. The contents of steroidal saponins in the product were 4.83-fold increased with recovery yields of 85.47%. The process achieved simple and effective enrichment and separation for steroidal saponins. The method provides a scientific basis for large-scale preparation of steroidal saponins from the Rhizoma Paridis and other plants.

  2. Sensitivity of the Enviroscan soil moisture capacitance probe to the presence of artificial macropores

    USDA-ARS?s Scientific Manuscript database

    Capacitance probes (CP) have been used to measure soil water contents in various applications. Effects of large macropores, cracks and other large heterogeneities within the CP sensitivity volume are sources of concerns related to such applications. The objective of this work was to evaluate the sen...

  3. Abnormal branching and regression of the notochord and its relationship to foregut abnormalities.

    PubMed

    Vleesch Dubois, V N; Quan Qi, B; Beasley, S W; Williams, A

    2002-04-01

    An abnormally positioned notochord has been reported in embryos that develop foregut abnormalities, vertebral defects and other abnormalities of the VATER association. This study examines the patterns of regression of the abnormal notochord in the rat model of the VATER association and investigates the relationship between developmental abnormalities of the notochord and those of the vertebra and foregut. Timed-pregnant Sprague-Dawley rats were given daily intraperitoneal injections of 1.75 mg/kg adriamycin on gestational days 6 - 9 inclusive. Rats were sacrificed between days 14 and 20 and their embryos harvested, histologically sectioned and stained and examined serially. The location and appearance of the degenerating notochord and its relationship to regional structural defects were analysed. All 26 embryos exposed to adriamycin developed foregut abnormalities and had an abnormal notochord. The notochord disappeared by a process of apoptotic degeneration that lagged behind that of the normal embryo: the notochord persisted in the abnormal embryo beyond day 17, whereas in the normal rat it had already disappeared. Similarly, formation of the nucleus pulposus was delayed. Vertebral abnormalities occurred when the notochord was ventrally-positioned. The notochord disappears during day 16 in the normal embryo whereas abnormal branches of the notochord persist until day 19 in the adriamycin-treated embryo. Degeneration of the notochord is dominated by apoptosis. An excessively ventrally-placed notochord is closely associated with abnormalities of the vertebral column, especially hemivertebrae.

  4. Investigating the interplay between substrate stiffness and ligand chemistry in directing mesenchymal stem cell differentiation within 3D macro-porous substrates.

    PubMed

    Haugh, Matthew G; Vaughan, Ted J; Madl, Christopher M; Raftery, Rosanne M; McNamara, Laoise M; O'Brien, Fergal J; Heilshorn, Sarah C

    2018-07-01

    Dimensionality can have a profound impact on stiffness-mediated differentiation of mesenchymal stem cells (MSCs). However, while we have begun to understand cellular response when encapsulated within 3D substrates, the behavior of cells within macro-porous substrates is relatively underexplored. The goal of this study was to determine the influence of macro-porous topographies on stiffness-mediated differentiation of MSCs. We developed macro-porous recombinant elastin-like protein (ELP) substrates that allow independent control of mechanical properties and ligand chemistry. We then used computational modeling to probe the impact of pore topography on the mechanical stimulus that cells are exposed to within these substrates, and finally we investigated stiffness induced biases towards adipogenic and osteogenic differentiation of MSCs within macro-porous substrates. Computational modeling revealed that there is significant heterogeneity in the mechanical stimuli that cells are exposed to within porous substrates and that this heterogeneity is predominantly due to the wide range of possible cellular orientations within the pores. Surprisingly, MSCs grown within 3D porous substrates respond to increasing substrate stiffness by up-regulating both osteogenesis and adipogenesis. These results demonstrate that within porous substrates the behavior of MSCs diverges from previously observed responses to substrate stiffness, emphasizing the importance of topography as a determinant of cellular behavior. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Formation of carbon nanosheets via simultaneous activation and catalytic carbonization of macroporous anion-exchange resin for supercapacitors application.

    PubMed

    Peng, Hui; Ma, Guofu; Sun, Kanjun; Mu, Jingjing; Zhang, Zhe; Lei, Ziqiang

    2014-12-10

    Two-dimensional mesoporous carbon nanosheets (CNSs) have been prepared via simultaneous activation and catalytic carbonization route using macroporous anion-exchange resin (AER) as carbon precursor and ZnCl2 and FeCl3 as activating agent and catalyst, respectively. The iron catalyst in the skeleton of the AER may lead to carburization to form a sheetlike structure during the carbonization process. The obtained CNSs have a large number of mesopores, a maximum specific surface area of 1764.9 m(2) g(-1), and large pore volume of 1.38 cm(3) g(-1). As an electrode material for supercapacitors application, the CNSs electrode possesses a large specific capacitance of 283 F g(-1) at 0.5 A g(-1) and excellent rate capability (64% retention ratio even at 50 A g(-1)) in 6 mol L(-1) KOH. Furthermore, CNSs symmetric supercapacitor exhibits specific energies of 17.2 W h kg(-1) at a power density of 224 W kg(-1) operated in the voltage range of 0-1.8 V in 0.5 mol L(-1) Na2SO4 aqueous electrolyte, and outstanding cyclability (retains about 96% initial capacitance after 5000 cycles).

  6. Study of Ni Metallization in Macroporous Si Using Wet Chemistry for Radio Frequency Cross-Talk Isolation in Mixed Signal Integrated Circuits

    PubMed Central

    Zhang, Xi; Xu, Chengkun; Chong, Kyuchul; Tu, King-Ning; Xie, Ya-Hong

    2011-01-01

    A highly conductive moat or Faraday cage of through-the-wafer thickness in Si substrate was proposed to be effective in shielding electromagnetic interference thereby reducing radio frequency (RF) cross-talk in high performance mixed signal integrated circuits. Such a structure was realized by metallization of selected ultra-high-aspect-ratio macroporous regions that were electrochemically etched in p− Si substrates. The metallization process was conducted by means of wet chemistry in an alkaline aqueous solution containing Ni2+ without reducing agent. It is found that at elevated temperature during immersion, Ni2+ was rapidly reduced and deposited into macroporous Si and a conformal metallization of the macropore sidewalls was obtained in a way that the entire porous Si framework was converted to Ni. A conductive moat was as a result incorporated into p− Si substrate. The experimentally measured reduction of crosstalk in this structure is 5~18 dB at frequencies up to 35 GHz. PMID:28879960

  7. Study of Ni Metallization in Macroporous Si Using Wet Chemistry for Radio Frequency Cross-Talk Isolation in Mixed Signal Integrated Circuits.

    PubMed

    Zhang, Xi; Xu, Chengkun; Chong, Kyuchul; Tu, King-Ning; Xie, Ya-Hong

    2011-05-25

    A highly conductive moat or Faraday cage of through-the-wafer thickness in Si substrate was proposed to be effective in shielding electromagnetic interference thereby reducing radio frequency (RF) cross-talk in high performance mixed signal integrated circuits. Such a structure was realized by metallization of selected ultra-high-aspect-ratio macroporous regions that were electrochemically etched in p - Si substrates. The metallization process was conducted by means of wet chemistry in an alkaline aqueous solution containing Ni 2+ without reducing agent. It is found that at elevated temperature during immersion, Ni 2+ was rapidly reduced and deposited into macroporous Si and a conformal metallization of the macropore sidewalls was obtained in a way that the entire porous Si framework was converted to Ni. A conductive moat was as a result incorporated into p - Si substrate. The experimentally measured reduction of crosstalk in this structure is 5~18 dB at frequencies up to 35 GHz.

  8. Ordered macroporous platinum electrode and enhanced mass transfer in fuel cells using inverse opal structure.

    PubMed

    Kim, Ok-Hee; Cho, Yong-Hun; Kang, Soon Hyung; Park, Hee-Young; Kim, Minhyoung; Lim, Ju Wan; Chung, Dong Young; Lee, Myeong Jae; Choe, Heeman; Sung, Yung-Eun

    2013-01-01

    Three-dimensional, ordered macroporous materials such as inverse opal structures are attractive materials for various applications in electrochemical devices because of the benefits derived from their periodic structures: relatively large surface areas, large voidage, low tortuosity and interconnected macropores. However, a direct application of an inverse opal structure in membrane electrode assemblies has been considered impractical because of the limitations in fabrication routes including an unsuitable substrate. Here we report the demonstration of a single cell that maintains an inverse opal structure entirely within a membrane electrode assembly. Compared with the conventional catalyst slurry, an ink-based assembly, this modified assembly has a robust and integrated configuration of catalyst layers; therefore, the loss of catalyst particles can be minimized. Furthermore, the inverse-opal-structure electrode maintains an effective porosity, an enhanced performance, as well as an improved mass transfer and more effective water management, owing to its morphological advantages.

  9. Interpenetrated Networks between Graphitic Carbon Infilling and Ultrafine TiO2 Nanocrystals with Patterned Macroporous Structure for High-Performance Lithium Ion Batteries.

    PubMed

    Zheng, Wenji; Yan, Zhijun; Dai, Yan; Du, Naixu; Jiang, Xiaobin; Dai, Hailing; Li, Xiangcun; He, Gaohong

    2017-06-21

    Interpenetrated networks between graphitic carbon infilling and ultrafine TiO 2 nanocrystals with patterned macropores (100-200 nm) were successfully synthesized. Polypyrrole layer was conformably coated on the primary TiO 2 nanoparticles (∼8 nm) by a photosensitive reaction and was then transformed into carbon infilling in the interparticle mesopores of the TiO 2 nanoparticles. Compared to the carbon/graphene supported TiO 2 nanoparticles or carbon coated TiO 2 nanostructures, the carbon infilling would provide a conductive medium and buffer layer for volume expansion of the encapsulated TiO 2 nanoparticles, thus enhancing conductivity and cycle stability of the C-TiO 2 anode materials for lithium ion batteries (LIBs). In addition, the macropores with diameters of 100-200 nm in the C-TiO 2 anode and the mesopores in carbon infilling could improve electrolyte transportation in the electrodes and shorten the lithium ion diffusion length. The C-TiO 2 electrode can provide a large capacity of 192.8 mA h g -1 after 100 cycles at 200 mA g -1 , which is higher than those of the pure macroporous TiO 2 electrode (144.8 mA h g -1 ), C-TiO 2 composite electrode without macroporous structure (128 mA h g -1 ), and most of the TiO 2 based electrodes in the literature. Importantly, the C-TiO 2 electrode exhibits a high rate performance and still delivers a high capacity of ∼140 mA h g -1 after 1000 cycles at 1000 mA g -1 (∼5.88 C), suggesting good lithium storage properties of the macroporous C-TiO 2 composites with high capacity, cycle stability, and rate capability. This work would be instructive for designing hierarchical porous TiO 2 based anodes for high-performance LIBs.

  10. A simple and effective approach to prepare injectable macroporous calcium phosphate cement for bone repair: Syringe-foaming using a viscous hydrophilic polymeric solution.

    PubMed

    Zhang, Jingtao; Liu, Weizhen; Gauthier, Olivier; Sourice, Sophie; Pilet, Paul; Rethore, Gildas; Khairoun, Khalid; Bouler, Jean-Michel; Tancret, Franck; Weiss, Pierre

    2016-02-01

    In this study, we propose a simple and effective strategy to prepare injectable macroporous calcium phosphate cements (CPCs) by syringe-foaming via hydrophilic viscous polymeric solution, such as using silanized-hydroxypropyl methylcellulose (Si-HPMC) as a foaming agent. The Si-HPMC foamed CPCs demonstrate excellent handling properties such as injectability and cohesion. After hardening the foamed CPCs possess hierarchical macropores and their mechanical properties (Young's modulus and compressive strength) are comparable to those of cancellous bone. Moreover, a preliminary in vivo study in the distal femoral sites of rabbits was conducted to evaluate the biofunctionality of this injectable macroporous CPC. The evidence of newly formed bone in the central zone of implantation site indicates the feasibility and effectiveness of this foaming strategy that will have to be optimized by further extensive animal experiments. A major challenge in the design of biomaterial-based injectable bone substitutes is the development of cohesive, macroporous and self-setting calcium phosphate cement (CPC) that enables rapid cell invasion with adequate initial mechanical properties without the use of complex processing and additives. Thus, we propose a simple and effective strategy to prepare injectable macroporous CPCs through syringe-foaming using a hydrophilic viscous polymeric solution (silanized-hydroxypropyl methylcellulose, Si-HPMC) as a foaming agent, that simultaneously meets all the aforementioned aims. Evidence from our in vivo studies shows the existence of newly formed bone within the implantation site, indicating the feasibility and effectiveness of this foaming strategy, which could be used in various CPC systems using other hydrophilic viscous polymeric solutions. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  11. Three-Dimensional Macroporous Polypyrrole-Derived Graphene Electrode Prepared by the Hydrogen Bubble Dynamic Template for Supercapacitors and Metal-Free Catalysts.

    PubMed

    Yang, Xiaoqing; Liu, Anran; Zhao, Yuewu; Lu, Huijia; Zhang, Yuanjian; Wei, Wei; Li, Ying; Liu, Songqin

    2015-10-28

    We report a general method for the fabrication of three-dimensional (3D) macroporous graphene/conducting polymer modified electrode and nitrogen-doped graphene modified electrode. This method involves three consecutive steps. First, the 3D macroporous graphene (3D MG) electrode was fabricated electrochemically by reducing graphene oxide dispersion on different conducting substrates and used hydrogen bubbles as the dynamic template. The morphology and pore size of 3D MG could be governed by the use of surfactants and the dynamics of bubble generation and departure. Second, 3D macroporous graphene/polypyrrole (MGPPy) composites were constructed via directly electropolymerizing pyrrole monomer onto the networks of 3D MG. Due to the benefit of the good conductivity of 3D MG and pseudocapacitance of PPy, the composites manifest outstanding area specific capacitance of 196 mF cm(-2) at a current density of 1 mA cm(-2). The symmetric supercapacitor device assembled by the composite materials had a good capacity property. Finally, the nitrogen-doped MGPPy (N-MGPPy or MGPPy-X) with 3D macroporous nanostructure and well-regulated nitrogen doping was prepared via thermal treatment of the composites. The resultant N-MGPPy electrode was explored as a good electrocatalyst for the oxygen reduction reaction (ORR) with the current density value of 5.56 mA cm(-2) (-0.132 V vs Ag/AgCl). Moreover, the fuel tolerance and durability under the electrochemical environment of the N-MGPPy catalyst were found to be superior to the Pt/C catalyst.

  12. Creation of Triple Hierarchical Micro-Meso-Macroporous N-doped Carbon Shells with Hollow Cores Toward the Electrocatalytic Oxygen Reduction Reaction

    NASA Astrophysics Data System (ADS)

    Xing, Ruohao; Zhou, Tingsheng; Zhou, Yao; Ma, Ruguang; Liu, Qian; Luo, Jun; Wang, Jiacheng

    2018-03-01

    A series of triple hierarchical micro-meso-macroporous N-doped carbon shells with hollow cores have been successfully prepared via etching N-doped hollow carbon spheres with CO2 at high temperatures. The surface areas, total pore volumes and micropore percentages of the CO2-activated samples evidently increase with increasing activation temperature from 800 to 950 °C, while the N contents show a contrary trend from 7.6 to 3.8 at%. The pyridinic and graphitic nitrogen groups are dominant among various N-containing groups in the samples. The 950 °C-activated sample (CANHCS-950) has the largest surface area (2072 m2 g-1), pore volume (1.96 cm3 g-1), hierarchical micro-mesopore distributions (1.2, 2.6 and 6.2 nm), hollow macropore cores ( 91 nm) and highest relative content of pyridinic and graphitic N groups. This triple micro-meso-macropore system could synergistically enhance the activity because macropores could store up the reactant, mesopores could reduce the transport resistance of the reactants to the active sites, and micropores could be in favor of the accumulation of ions. Therefore, the CANHCS-950 with optimized structure shows the optimal and comparable oxygen reduction reaction (ORR) activity but superior methanol tolerance and long-term durability to commercial Pt/C with a 4e--dominant transfer pathway in alkaline media. These excellent properties in combination with good stability and recyclability make CANHCSs among the most promising metal-free ORR electrocatalysts reported so far in practical applications. [Figure not available: see fulltext.

  13. Novel Biocompatible Thermoresponsive Poly(N-vinyl Caprolactam)/Clay Nanocomposite Hydrogels with Macroporous Structure and Improved Mechanical Characteristics.

    PubMed

    Shi, Kun; Liu, Zhuang; Yang, Chao; Li, Xiao-Ying; Sun, Yi-Min; Deng, Yi; Wang, Wei; Ju, Xiao-Jie; Xie, Rui; Chu, Liang-Yin

    2017-07-05

    Poly(N-vinyl caprolactam) (PVCL) hydrogels usually suffer from the imporous structure and poor mechanical characteristics as well as the toxicity of cross-linkers, although PVCL itself is biocompatible. In this paper, novel biocompatible thermoresponsive poly(N-vinyl caprolactam)/clay nanocomposite (PVCL-Clay) hydrogels with macroporous structure and improved mechanical characteristics are developed for the first time. The macroporosity in the hydrogel is introduced by using Pickering emulsions as templates, which contain N-vinyl caprolactam (VCL) monomer as dispersed phase and clay sheets as stabilizers at the interface. After polymerization, macropores are formed inside the hydrogels with the residual unreacted VCL droplets as templates. The three-dimensional PVCL polymer networks are cross-linked by the clay nanosheets. Due to the nanocomposite structure, the hydrogel exhibits better mechanical characteristics in comparison to the conventional PVCL hydrogels cross-linked by N,N'-methylene diacrylamide (BIS). The prepared PVCL-Clay hydrogel possesses remarkable temperature-responsive characteristics with a volume phase transition temperature (VPTT) around 35 °C, and provides a feasible platform for cell culture. With macroporous structure and good mechanical characteristics as well as flexible assembly performance, the proposed biocompatible thermoresponsive PVCL-Clay nanocomposite hydrogels are ideal material candidates for biomedical, analytical, and other applications such as entrapment of enzymes, cell culture, tissue engineering, and affinity and displacement chromatography.

  14. Enrichment and Purification of Syringin, Eleutheroside E and Isofraxidin from Acanthopanax senticosus by Macroporous Resin

    PubMed Central

    Yang, Fengjian; Yang, Lei; Wang, Wenjie; Liu, Yang; Zhao, Chunjian; Zu, Yuangang

    2012-01-01

    In order to screen a suitable resin for the preparative simultaneous separation and purification of syringin, eleutheroside E and isofraxidin from Acanthopanax senticosus, the adsorption and desorption properties of 17 widely used commercial macroporous resins were evaluated. According to our results, HPD100C, which adsorbs by the molecular tiers model, was the best macroporous resin, offering higher adsorption and desorption capacities and higher adsorption speed for syringin, eleutheroside E and isofraxidin than other resins. Dynamic adsorption and desorption tests were carried out to optimize the process parameters. The optimal conditions were as follows: for adsorption, processing volume: 24 BV, flow rate: 2 BV/h; for desorption, ethanol–water solution: 60:40 (v/v), eluent volume: 4 BV, flow rate: 3 BV/h. Under the above conditions, the contents of syringin, eleutheroside E and isofraxidin increased 174-fold, 20-fold and 5-fold and their recoveries were 80.93%, 93.97% and 93.79%, respectively. PMID:22942746

  15. Separation of scutellarin from crude extracts of Erigeron breviscapus (vant.) Hand. Mazz. by macroporous resins.

    PubMed

    Gao, Min; Huang, Wei; Liu, Chun-Zhao

    2007-10-15

    Scutellarin, a flavone glycoside, popularly used in the treatment of heart disease, has been efficiently separated using macroporous resins from crude extracts of Chinese medicinal plant Erigeron breviscapus (vant.) Hand. Mazz. HPD-800 resin offered the best adsorption and desorption capacity for scutellarin among the eight macroporous resins tested, and its adsorption data at 25 degrees C fit best to the Langmuir isotherm. The dynamic adsorption and desorption experiments have been carried out on a HPD-800 resin packed column to optimize the separation process of scutellarin from the crude extracts of E. breviscapus. After one run treatment with HPD-800 resin, the scutellarin content in the product was increased 15.69-fold from 2.61% to 40.96% with a recovery yield of 95.01%. The preparative separation process via adsorption-desorption method developed in this study provides a new approach for scale-up separation and purification of scutellarin for its wide pharmaceutical use.

  16. 3D macroporous graphene frameworks for supercapacitors with high energy and power densities.

    PubMed

    Choi, Bong Gill; Yang, Minho; Hong, Won Hi; Choi, Jang Wook; Huh, Yun Suk

    2012-05-22

    In order to develop energy storage devices with high power and energy densities, electrodes should hold well-defined pathways for efficient ionic and electronic transport. Herein, we demonstrate high-performance supercapacitors by building a three-dimensional (3D) macroporous structure that consists of chemically modified graphene (CMG). These 3D macroporous electrodes, namely, embossed-CMG (e-CMG) films, were fabricated by using polystyrene colloidal particles as a sacrificial template. Furthermore, for further capacitance boost, a thin layer of MnO(2) was additionally deposited onto e-CMG. The porous graphene structure with a large surface area facilitates fast ionic transport within the electrode while preserving decent electronic conductivity and thus endows MnO(2)/e-CMG composite electrodes with excellent electrochemical properties such as a specific capacitance of 389 F/g at 1 A/g and 97.7% capacitance retention upon a current increase to 35 A/g. Moreover, when the MnO(2)/e-CMG composite electrode was asymmetrically assembled with an e-CMG electrode, the assembled full cell shows remarkable cell performance: energy density of 44 Wh/kg, power density of 25 kW/kg, and excellent cycle life.

  17. Free-Standing Air Cathodes Based on 3D Hierarchically Porous Carbon Membranes: Kinetic Overpotential of Continuous Macropores in Li-O2 Batteries.

    PubMed

    Xu, Shu-Mao; Liang, Xiao; Ren, Zhi-Chu; Wang, Kai-Xue; Chen, Jie-Sheng

    2018-06-04

    Free-standing macroporous air electrodes with enhanced interfacial contact, rapid mass transport, and tailored deposition space for large amounts of Li 2 O 2 are essential for improving the rate performance of Li-O 2 batteries. An ordered mesoporous carbon membrane with continuous macroporous channels was prepared by inversely topological transformation from ZnO nanorod array. Utilized as a free-standing air cathode for Li-O 2 battery, the hierarchically porous carbon membrane shows superior rate performance. However, the increased cross-sectional area of the continuous macropores on the cathode surface leads to a kinetic overpotential with large voltage hysteresis and linear voltage variation against Butler-Volmer behavior. The kinetics were investigated based on the rate-determining step of second electron transfer accompanied by migration of Li + in solid or quasi-solid intermediates. These discoveries shed light on the design of the air cathode for Li-O 2 batteries with high-rate performance. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. A composite chitosan-gelatin bi-layered, biomimetic macroporous scaffold for blood vessel tissue engineering.

    PubMed

    Badhe, Ravindra V; Bijukumar, Divya; Chejara, Dharmesh R; Mabrouk, Mostafa; Choonara, Yahya E; Kumar, Pradeep; du Toit, Lisa C; Kondiah, Pierre P D; Pillay, Viness

    2017-02-10

    A composite chitosan-gelatin macroporous hydrogel-based scaffold with bi-layered tubular architecture was engineered by solvent casting-co-particulate leaching. The scaffold constituted an inner macroporous layer concealed by a non-porous outer layer mimicking the 3D matrix of blood vessels with cellular adhesion and proliferation. The scaffold was evaluated for its morphological, physicochemical, physicomechanical and biodurability properties employing SEM, FTIR, DSC, XRD, porositometry, rheology and texture analysis. The fluid uptake and biodegradation in the presence of lysozymes was also investigated. Cellular attachment and proliferation was analysed using human dermal fibroblasts (HDF-a) seeded onto the scaffold and evaluated by MTT assay, SEM, and confocal microscopy. Results demonstrated that the scaffold had a desirable tensile strength=95.81±11kPa, elongation at break 112.5±13%, porosity 82% and pores between 100 and 230μm, 50% in vitro biodegradation at day 16 and proliferated fibroblasts over 20 days. These results demonstrate that scaffold may be an excellent tubular archetype for blood vessel tissue engineering. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Preparation of three-dimensional macroporous chitosan-gelatin B microspheres and HepG2-cell culture.

    PubMed

    Huang, Fang; Cui, Long; Peng, Cheng-Hong; Wu, Xu-Bo; Han, Bao-San; Dong, Ya-Dong

    2016-12-01

    Chitosan-gelatin B microspheres with an open, interconnected, highly macroporous (100-200 µm) structure were prepared via a three-step protocol combining freeze-drying with an electrostatic and ionic cross-linking method. Saturated tripolyphosphate ethanol solution (85% ethanol) was chosen as the crosslinking agent to prevent destruction of the porous structure and to improve the biostability of the chitosan-gelatin B microspheres, with N-(3-dimethylaminopropyl)-N'-ethyl-carbodiimide/N-hydroxysuccinimide as a second crosslinking agent to react with gelatin A and fixed chitosan-gelatin B microspheres to attain improved biocompatibility. Water absorption of the three-dimensional macroporous chitosan-gelatin B microspheres (3D-P-CGMs) was 12.84, with a porosity of 85.45%. In vitro lysozyme degradation after 1, 3, 5, 7, 10, 14, and 21 days showed improved biodegradation in the 3D-P-CGMs. The morphology of human hepatoma cell lines (HepG2 cells) cultured on the 3D-P-CGMs was spherical, unlike that of cells cultured under traditional two-dimensional conditions. Scanning electron microscopy and paraffin sections were used to confirm the porous structure of the 3D-P-CGMs. HepG2 cells were able to migrate inside through the pore. Cell proliferation and levels of albumin and lactate dehydrogenase suggested that the 3D-P-CGMs could provide a larger specific surface area and an appropriate microenvironment for cell growth and survival. Hence, the 3D-P-CGMs are eminently suitable as macroporous scaffolds for cell cultures in tissue engineering and cell carrier studies. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

  20. Detachment of affinity-captured bioparticles by elastic deformation of a macroporous hydrogel

    PubMed Central

    Dainiak, Maria B.; Kumar, Ashok; Galaev, Igor Yu.; Mattiasson, Bo

    2006-01-01

    Adsorption of bioparticles to affinity surfaces involves polyvalent interactions, complicating greatly the recovery of the adsorbed material. A unique system for the efficient binding and release of different cells and particles is described. Affinity-bound bioparticles and synthetic particles are detached from the macroporous hydrogel matrix, a so-called cryogel, when the cryogel undergoes elastic deformation. The particle detachment upon elastic deformation is believed to be due to breaking of many of the multipoint attachments between the particles and the affinity matrix and the change in the distance between affinity ligands when the matrix is deformed. However, no release of affinity-bound protein occurred upon elastic deformation. The phenomenon of particle detachment upon elastic deformation is believed to be of a generic nature, because it was demonstrated for a variety of bioparticles of different sizes and for synthetic particles, for different ligand–receptor pairs (IgG–protein A, sugar–ConA, metal ion–chelating ligand), and when the deformation was caused by either external forces (mechanical deformation) or internal forces (the shrinkage of thermosensitive, macroporous hydrogel upon an increase in temperature). The elasticity of cryogel monoliths ensures high recovery of captured cells under mild conditions, with highly retained viability. This property, along with their continuous porous structure makes cryogel monoliths very attractive for applications in affinity cell separation. PMID:16418282

  1. Impact of fire on macropore flow and the hydraulic conductivity of near-surface blanket peat

    NASA Astrophysics Data System (ADS)

    Holden, Joseph; Wearing, Catherine; Palmer, Sheila; Jackson, Benjamin; Johnston, Kerrylyn; Brown, Lee

    2013-04-01

    Peatlands can be subject to wildfire or deliberate burning in many locations. Wildfires are known to impact soil properties and runoff production in most soil types but relatively little work has been conducted on peatlands. Furthermore in large parts of the UK uplands prescribed vegetation burning on peat has taken place at regular intervals (e.g. every 8-25 years) on patches of around 300-900 sq. metres over the past century to support increased grouse populations for sport shooting. However, there have been few studies on how these prescribed fires influence near-surface hydrology. It is known that macropores transport a large proportion of flow in near-surface peat layers and we investigated their role in flow transport for fire sites using tension infiltrometers. Measurements were performed, at replicated hillslope positions to control for slope position effects, on unburnt peat (U) and where prescribed burning had taken place two years (P2), four years (P4) and >15 years (P15+) prior to sampling. For the prescribed burning plots, vegetation burning had also occurred at around a 15-20 year interval for most of the past century. We also sampled a nearby wildfire site (W) with the same sampling design where wildfire had occurred four months prior to sampling. Both the contribution of macropore flow to overall infiltration, and the saturated hydraulic conductivity, were significantly lower in the recently burnt sites (W, P2, P4), compared to P15+ and U. There was no significant difference in macropore flow contributions, effective macroporosity and saturated hydraulic conductivity between P15+ and U. The results suggest fire influences the near-surface hydrological functioning of peatlands but that 'recovery' for some hydrological processes to prescribed vegetation burning may be possible within two decades if there are no further fires.

  2. Designed catalysts from Pt nanoparticles supported on macroporous oxides for selective isomerization of n-hexane.

    PubMed

    An, Kwangjin; Alayoglu, Selim; Musselwhite, Nathan; Na, Kyungsu; Somorjai, Gabor A

    2014-05-14

    Selective isomerization toward branched hydrocarbons is an important catalytic process in oil refining to obtain high-octane gasoline with minimal content of aromatic compounds. Colloidal Pt nanoparticles with controlled sizes of 1.7, 2.7, and 5.5 nm were deposited onto ordered macroporous oxides of SiO2, Al2O3, TiO2, Nb2O5, Ta2O5, and ZrO2 to investigate Pt size- and support-dependent catalytic selectivity in n-hexane isomerization. Among the macroporous oxides, Nb2O5 and Ta2O5 exhibited the highest product selectivity, yielding predominantly branched C6 isomers, including 2- or 3-methylpentane, as desired products of n-hexane isomerization (140 Torr n-hexane and 620 Torr H2 at 360 °C). In situ characterizations including X-ray diffraction and ambient-pressure X-ray photoelectron spectroscopy showed that the crystal structures of the oxides in Pt/oxide catalysts were not changed during the reaction and oxidation states of Nb2O5 were maintained under both H2 and O2 conditions. Fourier transform infrared spectra of pyridine adsorbed on the oxides showed that Lewis sites were the dominant acidic site of the oxides. Macroporous Nb2O5 and Ta2O5 were identified to play key roles in the selective isomerization by charge transfer at Pt-oxide interfaces. The selectivity was revealed to be Pt size-dependent, with improved isomer production as Pt sizes increased from 1.7 to 5.5 nm. When 5.5 nm Pt nanoparticles were supported on Nb2O5 or Ta2O5, the selectivity toward branched C6 isomers was further increased, reaching ca. 97% with a minimum content of benzene, due to the combined effects of the Pt size and the strong metal-support interaction.

  3. Abnormal tuning of saccade-related cells in pontine reticular formation of strabismic monkeys.

    PubMed

    Walton, Mark M G; Mustari, Michael J

    2015-08-01

    Strabismus is a common disorder, characterized by a chronic misalignment of the eyes and numerous visual and oculomotor abnormalities. For example, saccades are often highly disconjugate. For humans with pattern strabismus, the horizontal and vertical disconjugacies vary with eye position. In monkeys, manipulations that disturb binocular vision during the first several weeks of life result in a chronic strabismus with characteristics that closely match those in human patients. Early onset strabismus is associated with altered binocular sensitivity of neurons in visual cortex. Here we test the hypothesis that brain stem circuits specific to saccadic eye movements are abnormal. We targeted the pontine paramedian reticular formation, a structure that directly projects to the ipsilateral abducens nucleus. In normal animals, neurons in this structure are characterized by a high-frequency burst of spikes associated with ipsiversive saccades. We recorded single-unit activity from 84 neurons from four monkeys (two normal, one exotrope, and one esotrope), while they made saccades to a visual target on a tangent screen. All 24 neurons recorded from the normal animals had preferred directions within 30° of pure horizontal. For the strabismic animals, the distribution of preferred directions was normal on one side of the brain, but highly variable on the other. In fact, 12/60 neurons recorded from the strabismic animals preferred vertical saccades. Many also had unusually weak or strong bursts. These data suggest that the loss of corresponding binocular vision during infancy impairs the development of normal tuning characteristics for saccade-related neurons in brain stem. Copyright © 2015 the American Physiological Society.

  4. Preparation of ordered mesoporous and macroporous thermoplastic polyurethane surfaces for potential medical applications.

    PubMed

    Chennell, Philip; Feschet-Chassot, Emmanuelle; Sautou, Valérie; Mailhot-Jensen, Bénédicte

    2018-05-01

    Thermoplastic polyurethanes are widely used in medical devices. In order to limit some of their shortfalls, like microbial attachment, surfaces modifications can be required. In this work, a two-step replication method was used to create ordered macroporous and mesoporous thermoplastic polyurethane surfaces using anodic aluminum oxide as master template. The intermediate mould materials that were tested were polystyrene and a polyacrylate resin with inorganic filler. All obtained surfaces were characterized by scanning electron microscopy. The initial anodic aluminum oxide surfaces possessed macro or mesopores, function of anodization conditions. The intermediate mould structure correctly replicated the pattern, but the polystyrene surface structures (pillars) were less resistant than the polyacrylate resin ones. The thermoplastic polyurethane pattern possessed macropores or mesopores of about 130 nm or 46 nm diameter and of about 300 nm or 99 nm interpore distances, respectively, in accordance with the initial pattern. Thermoplastic polyurethanes pore depth was however less than initial anodic aluminum oxide pore depth, linked to an incomplete replication during intermediate mould preparation (60 to 90% depth replication). The correct replication of the original pattern confirms that this novel fabrication method is a promising route for surface patterning of thermoplastic polyurethanes that could be used for medical applications.

  5. Preparative Separation and Purification of the Total Flavonoids in Scorzonera austriaca with Macroporous Resins.

    PubMed

    Xie, Yang; Guo, Qiu-Shi; Wang, Guang-Shu

    2016-06-13

    The use of macroporous resins for the separation and purification of total flavonoids to obtain high-purity total flavonoids from Scorzonera austriaca was studied. The optimal conditions for separation and purification of total flavonoids in S. austriaca with macroporous resins were as follows: D4020 resin columns were loaded with crude flavonoid extract solution, and after reaching adsorptive saturation, the columns were eluted successively with 5 bed volumes (BV) of water, 5 BV of 5% (v/v) aqueous ethanol and 5 BV of 30% (v/v) aqueous ethanol at an elute flow rate of 2 BV·h(-1). Total flavonoids were obtained from the 30% aqueous ethanol eluate by vacuum distillation recovery. The content of flavonoid compounds in the total flavonoids was 93.5%, which represents an improvement by about 150%. In addition, five flavonoid compounds in the product were identified as 2″-O-β-d-xylopyranosyl isoorientin, 6-C-α-l-arabipyranosyl orientin, orientin, isoorientin and vitexin by LC-ESI-MS analysis and internal standard methods. The results in this study could represent a method for the large-scale production of total flavonoids from S. austriaca.

  6. Visualizing how cancer chromosome abnormalities form in living cells

    Cancer.gov

    For the first time, scientists have directly observed events that lead to the formation of a chromosome abnormality that is often found in cancer cells. The abnormality, called a translocation, occurs when part of a chromosome breaks off and becomes attac

  7. Enhanced Efficiency of Dye-Sensitized Solar Cells with Mesoporous-Macroporous TiO2 Photoanode Obtained Using ZnO Template

    NASA Astrophysics Data System (ADS)

    Pham, Trang T. T.; Mathews, Nripan; Lam, Yeng-Ming; Mhaisalkar, Subodh

    2017-06-01

    Improved light harvesting efficiency can be achieved by enhancing the optical properties of the titanium dioxide (TiO2) photoanode in dye-sensitized solar cells (DSSCs), leading to higher power conversion efficiency. By incorporating submicrometer cavities in TiO2 mesoporous film, using zinc oxide (ZnO) particles as a template, a bimodal pore size structure has been created, called a mesoporous-macroporous nanostructure. This photoanode structure consists of 20-nm TiO2 nanoparticles with two kinds of pores with size of 20 nm (mesopores) and 500 nm (macropores). Energy-dispersive x-ray spectroscopy and x-ray diffraction studies showed no trace of ZnO in the TiO2 after removal by TiCl4 treatment. Higher diffuse transmittance of this film compared with the standard transparent photoanode provides evidence of improved light scattering. When employed in a device, the incident-photon-to-current efficiency of ZnO-assisted devices showed enhancement at longer wavelengths, corresponding to the Mie light scattering effect with the macropores as scattering centers. This resulted in overall higher power conversion efficiency of the DSSC. In this work, a nonvolatile gel ionic liquid was used as the electrolyte to also demonstrate the benefit of this structure in combination with a viscous electrolyte and its promising application to prolong the stability of DSSCs.

  8. Novel three-dimensionally ordered macroporous Fe3+-doped TiO2 photocatalysts for H2 production and degradation applications

    NASA Astrophysics Data System (ADS)

    Yan, Xiaoqing; Xue, Chao; Yang, Bolun; Yang, Guidong

    2017-02-01

    Novel three-dimensionally ordered macroporous (3DOM) Fe3+-doped TiO2 photocatalysts were prepared using a colloidal crystal template method with low-cost raw material including ferric trichloride, isopropanol, tetrabutyl titanate and polymethyl methacrylate. The as-prepared 3DOM Fe3+-doped TiO2 photocatalysts were characterized by various analytical techniques. TEM and SEM results showed that the obtained photocatalysts possess well-ordered macroporous structure in three dimensional orientations. As proved by XPS and EDX analysis that Fe3+ ions have been introduced TiO2 lattice and the doped Fe3+ ions can act as the electron acceptor/donor centers to significantly enhance the electron transfer from the bulk to surface of TiO2, resulting in more electrons could take part in the oxygen reduction process thereby decreasing the recombination rate of photogenerated charges. Meanwhile, the 3DOM architecture with the feature of interfacial chemical reaction active sites and optical absorption active sites is remarkably favorable for the reactant transfer and light trapping in the photoreaction process. As a result, the 3DOM Fe3+-doped TiO2 photocatalysts show the considerably higher photocatalytic activity for decomposition of the Rhodamine B (RhB) and the generation of hydrogen under visible light irradiation due to the synergistic effects of open, interconnected macroporous network and metal ion doping.

  9. Porosity change after gypsum crust formation on macro-porous limestones

    NASA Astrophysics Data System (ADS)

    Dewanckele, Jan; Cnudde, Veerle; de Kock, Tim; Boone, Marijn; Boone, Matthieu; van Hoorebeke, Luc; Jacobs, Patric

    2010-05-01

    The deterioration of stone is a complex process in which physical, biological and chemical mechanisms are involved. In this research, pore structure changes inside two types of porous limestone were analyzed before, during and after strong acid tests with SO2. Sulphatation and crust formation phenomena on natural building stones exposed to a polluted environment, are largely described in literature. As far as rocks rich in calcium carbonate are concerned, the main processes involved are the dissolution of the calcium carbonate and the formation of gypsum (CaSO4.2H2O) in presence of an acid atmosphere. The low mobility of this newly formed salt favours its accumulation in porous materials and at the surface of less porous media. The main actor in the process of gypsum crystallization on limestone is the aggressive sulphur dioxide gas (SO2). In this study, the Savonnières and Euville limestone were subjected to tests with a strong acid. According to the standard EN 13919:2002E, samples were put in acid environment for 21 days. At the bottom of the container a mixture of 500 ± 10 ml H2SO3 and 150 ± 10 ml de-mineralized H2O was added. No airborne particles or oxides of nitrogen (NOx) were added. Before exposure, after 6 days in the polluted environment and at the end of the test, the two samples were scanned with X-ray computed tomography (X-ray CT) at the Centre for X-ray Tomography at Ghent University, Belgium (UGCT; www.ugct.ugent.be). This visualization technique allows 2D and 3D reconstructions on a micrometer scale of the internal structure of an object without damaging the material. It thus enables to scan the same sample in a sequential way. In order to obtain information about the sample's interior of which the characteristics can be compared before, during and after the test, the same scanning parameters (exposure time, amount of frames, energy, etc.) were used. In addition, the same adjustments like beam hardening correction, normalizing, ring and spot

  10. Drug delivery properties of macroporous polystyrene solid foams.

    PubMed

    Canal, Cristina; Aparicio, Rosa Maria; Vilchez, Alejandro; Esquena, Jordi; García-Celma, Maria José

    2012-01-01

    Polymeric porous foams have been evaluated as possible new pharmaceutical dosage forms. These materials were obtained by polymerization in the continuous phase of highly concentrated emulsions prepared by the phase inversion temperature method. Their porosity, specific surface and surface topography were characterized, and the incorporation and release of active principles was studied using ketoprofen as model lipophilic molecule. Solid foams with very high pore volume, mainly inside macropores, were obtained by this method. The pore morphology of the materials was characterized, and very rough topography was observed, which contributed to their nearly superhydrophobic properties. These solid foams could be used as delivery systems for active principles with pharmaceutical interest, and in the present work ketoprofen was used as a model lipophilic molecule. Drug incorporation and release was studied from solid foam disks, using different concentrations of the loading solutions, achieving a delayed release with short lag-time.

  11. Acetylene Black Induced Heterogeneous Growth of Macroporous CoV2O6 Nanosheet for High-Rate Pseudocapacitive Lithium-Ion Battery Anode.

    PubMed

    Zhang, Lei; Zhao, Kangning; Luo, Yanzhu; Dong, Yifan; Xu, Wangwang; Yan, Mengyu; Ren, Wenhao; Zhou, Liang; Qu, Longbing; Mai, Liqiang

    2016-03-23

    Metal vanadates suffer from fast capacity fading in lithium-ion batteries especially at a high rate. Pseudocapacitance, which is associated with surface or near-surface redox reactions, can provide fast charge/discharge capacity free from diffusion-controlled intercalation processes and is able to address the above issue. In this work, we report the synthesis of macroporous CoV2O6 nanosheets through a facile one-pot method via acetylene black induced heterogeneous growth. When applied as lithium-ion battery anode, the macroporous CoV2O6 nanosheets show typical features of pseudocapacitive behavior: (1) currents that are mostly linearly dependent on sweep rate and (2) redox peaks whose potentials do not shift significantly with sweep rate. The macroporous CoV2O6 nanosheets display a high reversible capacity of 702 mAh g(-1) at 200 mA g(-1), excellent cyclability with a capacity retention of 89% (against the second cycle) after 500 cycles at 500 mA g(-1), and high rate capability of 453 mAh g(-1) at 5000 mA g(-1). We believe that the introduction of pseudocapacitive properties in lithium battery is a promising direction for developing electrode materials with high-rate capability.

  12. [Study on the extraction process and macroporous resin for purification of Timosaponin B II].

    PubMed

    Liu, Yan-Ping; Ding, Yue; Zhang, Tong; Wang, Bing; Cai, Zhen-Zhen; Tao, Jian-Sheng

    2013-06-01

    To optimize the extraction process and macroporous resin for purification of Timosaponin B II from Anemarrhena asphodeloides. Orthogonal design L9 (34) was employed to optimize the circumfluence extraction conditions by taking the extraction yield of Timosaponin B II as index. The absorption-desorption characteristics of eight kinds of macroporous resins were evaluated, then the best resin was chosen to optimize the purification process conditions. The optimum extraction conditions were as follows: the herb was extracted for 2 times (2 hours each time) with 8.5-fold 50% ethanol at the first time and 6-fold 50% ethanol at the second time. HPD100 resin showed a good property for the absorption-desorption of Timosaponin B II. The optimum technological conditions of HPD100 resin were as follows:the solution concentration was 0.23 mg/mL, the amount of saturated adsorption at 4/5 body volumn (BV) resin, the HPD100 resin was washed with 3 BV water and 6 BV 20% ethanol solution to remove the impurity, then the Timosaponin B II was desorbed by 5 BV ethanol solution. The purity of Timosaponin B II was about 50%. The optimized extraction process and purification is stable, efficient and suitable for industrial production.

  13. Biodegradable FeMnSi Sputter-Coated Macroporous Polypropylene Membranes for the Sustained Release of Drugs

    PubMed Central

    Fornell, Jordina; Soriano, Jorge; Guerrero, Miguel; Sirvent, Juan de Dios; Ferran-Marqués, Marta; Ibáñez, Elena; Barrios, Leonardo; Baró, Maria Dolors; Suriñach, Santiago; Nogués, Carme; Sort, Jordi; Pellicer, Eva

    2017-01-01

    Pure Fe and FeMnSi thin films were sputtered on macroporous polypropylene (PP) membranes with the aim to obtain biocompatible, biodegradable and, eventually, magnetically-steerable platforms. Room-temperature ferromagnetic response was observed in both Fe- and FeMnSi-coated membranes. Good cell viability was observed in both cases by means of cytotoxicity studies, though the FeMnSi-coated membranes showed higher biodegradability than the Fe-coated ones. Various strategies to functionalize the porous platforms with transferrin-Alexa Fluor 488 (Tf-AF488) molecules were tested to determine an optimal balance between the functionalization yield and the cargo release. The distribution of Tf-AF488 within the FeMnSi-coated PP membranes, as well as its release and uptake by cells, was studied by confocal laser scanning microscopy. A homogeneous distribution of the drug within the membrane skeleton and its sustained release was achieved after three consecutive impregnations followed by the addition of a layer made of gelatin and maltodextrin, which prevented exceedingly fast release. The here-prepared organic-inorganic macroporous membranes could find applications as fixed or magnetically-steerable drug delivery platforms. PMID:28672792

  14. Dual permeability modeling of tile drain management influences on hydrologic and nutrient transport characteristics in macroporous soil

    NASA Astrophysics Data System (ADS)

    Frey, Steven K.; Hwang, Hyoun-Tae; Park, Young-Jin; Hussain, Syed I.; Gottschall, Natalie; Edwards, Mark; Lapen, David R.

    2016-04-01

    Tile drainage management is considered a beneficial management practice (BMP) for reducing nutrient loads in surface water. In this study, 2-dimensional dual permeability models were developed to simulate flow and transport following liquid swine manure and rhodamine WT (strongly sorbing) tracer application on macroporous clay loam soils under controlled (CD) and free drainage (FD) tile management. Dominant flow and transport characteristics were successfully replicated, including higher and more continuous tile discharge and lower peak rhodamine WT concentrations in FD tile effluent; in relation to CD, where discharge was intermittent, peak rhodamine concentrations higher, and mass exchange from macropores into the soil matrix greater. Explicit representation of preferential flow was essential, as macropores transmitted >98% of surface infiltration, tile flow, and tile solute loads for both FD and CD. Incorporating an active 3rd type lower boundary condition that facilitated groundwater interaction was imperative for simulating CD, as the higher (relative to FD) water table enhanced water and soluble nutrient movement from the soil profile into deeper groundwater. Scenario analysis revealed that in conditions where slight upwards hydraulic gradients exist beneath tiles, groundwater upwelling can influence the concentration of surface derived solutes in tile effluent under FD conditions; whereas the higher and flatter CD water table can restrict groundwater upwelling. Results show that while CD can reduce tile discharge, it can also lead to an increase in surface-application derived nutrient concentrations in tile effluent and hence surface water receptors, and it can promote NO3 loading into groundwater. This study demonstrates dual permeability modeling as a tool for increasing the conceptual understanding of tile drainage BMPs.

  15. Site selective generation of sol-gel deposits in layered bimetallic macroporous electrode architectures.

    PubMed

    Lalo, Hélène; Bon-Saint-Côme, Yémima; Plano, Bernard; Etienne, Mathieu; Walcarius, Alain; Kuhn, Alexander

    2012-02-07

    The elaboration of an original composite bimetallic macroporous electrode containing a site-selective sol-gel deposit is reported. Regular colloidal crystals, obtained by a modified Langmuir-Blodgett approach, are used as templates for the electrogeneration of the desired metals in the form of a well-defined layered bimetallic porous electrode. This porous matrix shows a spatially modulated electroactivity which is subsequently used as a strategy for targeted electrogeneration of a sol-gel deposit, exclusively in one predefined part of the porous electrode.

  16. The growth of high density network of MOF nano-crystals across macroporous metal substrates - Solvothermal synthesis versus rapid thermal deposition

    NASA Astrophysics Data System (ADS)

    Maina, James W.; Gonzalo, Cristina Pozo; Merenda, Andrea; Kong, Lingxue; Schütz, Jürg A.; Dumée, Ludovic F.

    2018-01-01

    Fabrication of metal organic framework (MOF) films and membranes across macro-porous metal substrates is extremely challenging, due to the large pore sizes across the substrates, poor wettability, and the lack of sufficient reactive functional groups on the surface, which prevent high density nucleation of MOF crystals. Herein, macroporous stainless steel substrates (pore size 44 × 40 μm) are functionalized with amine functional groups, and the growth of ZIF-8 crystals investigated through both solvothermal synthesis and rapid thermal deposition (RTD), to assess the role of synthesis routes in the resultant membranes microstructure, and subsequently their performance. Although a high density of well interconnected MOF crystals was observed across the modified substrates following both techniques, RTD was found to be a much more efficient route, yielding high quality membranes under 1 h, as opposed to the 24 h required for solvothermal synthesis. The RTD membranes also exhibited high gas permeance, with He permeance of up to 2.954 ± 0.119 × 10-6 mol m-2 s-1 Pa-1, and Knudsen selectivities for He/N2, Ar/N2 and CO2/N2, suggesting the membranes were almost defect free. This work opens up route for efficient fabrication of MOF films and membranes across macro-porous metal supports, with potential application in electrically mediated separation applications.

  17. Pericellular innervation of neurons expressing abnormally hyperphosphorylated tau in the hippocampal formation of Alzheimer's disease patients.

    PubMed

    Blazquez-Llorca, Lidia; Garcia-Marin, Virginia; Defelipe, Javier

    2010-01-01

    Neurofibrillary tangles (NFT) represent one of the main neuropathological features in the cerebral cortex associated with Alzheimer's disease (AD). This neurofibrillary lesion involves the accumulation of abnormally hyperphosphorylated or abnormally phosphorylated microtubule-associated protein tau into paired helical filaments (PHF-tau) within neurons. We have used immunocytochemical techniques and confocal microscopy reconstructions to examine the distribution of PHF-tau-immunoreactive (ir) cells, and their perisomatic GABAergic and glutamatergic innervations in the hippocampal formation and adjacent cortex of AD patients. Furthermore, correlative light and electron microscopy was employed to examine these neurons and the perisomatic synapses. We observed two patterns of staining in PHF-tau-ir neurons, pattern I (without NFT) and pattern II (with NFT), the distribution of which varies according to the cortical layer and area. Furthermore, the distribution of both GABAergic and glutamatergic terminals around the soma and proximal processes of PHF-tau-ir neurons does not seem to be altered as it is indistinguishable from both control cases and from adjacent neurons that did not contain PHF-tau. At the electron microscope level, a normal looking neuropil with typical symmetric and asymmetric synapses was observed around PHF-tau-ir neurons. These observations suggest that the synaptic connectivity around the perisomatic region of these PHF-tau-ir neurons was apparently unaltered.

  18. Nickel oxide film with open macropores fabricated by surfactant-assisted anodic deposition for high capacitance supercapacitors.

    PubMed

    Wu, Mao-Sung; Wang, Min-Jyle

    2010-10-07

    Nickel oxide film with open macropores prepared by anodic deposition in the presence of surfactant shows a very high capacitance of 1110 F g(-1) at a scan rate of 10 mV s(-1), and the capacitance value reduces to 950 F g(-1) at a high scan rate of 200 mV s(-1).

  19. An Efficient Protocol for Preparation of Gallic Acid from Terminalia bellirica (Gaertn.) Roxb by Combination of Macroporous Resin and Preparative High-Performance Liquid Chromatography.

    PubMed

    Zou, Denglang; Chen, Tao; Chen, Chen; Li, Hongmei; Liu, Yongling; Li, Yulin

    2016-08-01

    In this article, macroporous resin column chromatography and preparative high-performance liquid chromatography were applied for preparation of gallic acid from Terminalia bellirica (Gaertn.) Roxb. In the first step, six kinds of resins were investigated by adsorption and desorption tests and AB-8 macroporous resin was selected for the enrichment of gallic acid. As a result, 20 g of gallic acid at a purity of 71% could be separated from 100 g of crude extract in which the content of gallic acid was 16.7% and the recovery of gallic acid reached 85.0%. In the second step, preparative high-performance liquid chromatography was selected to purify gallic acid. As a result, 640 mg of gallic acid at a purity of 99.1% was obtained from 1 g of sample in 35 min. The results demonstrated that macroporous resin coupled with preparative high-performance liquid chromatography was suitable for preparation of gallic acid from T. bellirica (Gaertn.) Roxb. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Macroporous monoliths for trace metal extraction from seawater

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

    Yue, Yanfeng; Mayes, Richard; Gill, Gary A.

    2015-05-29

    The viability of seawater-based uranium recovery depends on the uranium adsorption rate and capacity, since the concentration of uranium in the oceans is relatively low (3.3 μgL⁻¹). An important consideration for a fast adsorption is to maximize the adsorption properties of adsorbents such as surface areas and pore structures, which can greatly improve the kinetics of uranium extraction and the adsorption capacity simultaneously. Following this consideration, macroporous monolith adsorbents were prepared from the copolymerization of acrylonitrile (AN) and N, N’-methylenebis(acrylamide) (MBAAm) based on a cryogel method using both hydrophobic and hydrophilic monomers. The monolithic sorbents were tested with simulated seawatermore » containing a high uranyl concentration (–6 ppm) and the uranium adsorption results showed that the adsorption capacities are strongly influenced by the ratio of monomer to the crosslinker, i.e., the density of the amidoxime groups. The preliminary seawater testing indicates the high salinity content of seawater does not hinder the adsorption of uranium.« less

  1. Macroporous monoliths for trace metal extraction from seawater

    DOE PAGES

    Yue, Yanfeng; Mayes, Richard T.; Gill, Gary; ...

    2015-05-29

    The viability of seawater-based uranium recovery depends on the uranium adsorption rate and capacity, since the concentration of uranium in the oceans is relatively low (3.3 gL -1). An important consideration for a fast adsorption is to maximize the adsorption properties of adsorbents such as surface areas and pore structures, which can greatly improve the kinetics of uranium extraction and the adsorption capacity simultaneously. Following this consideration, macroporous monolith adsorbents were prepared from the copolymerization of acrylonitrile (AN) and N,N -methylenebis(acrylamide) (MBAAm) based on a cryogel method using both hydrophobic and hydrophilic monomers. The monolithic sorbents were tested with simulatedmore » seawater containing a high uranyl concentration (–6 ppm) and the uranium adsorption results showed that the adsorption capacities are strongly influenced by the ratio of monomer to the crosslinker, i.e., the density of the amidoxime groups. Furthermore, the preliminary seawater testing indicates the high salinity content of seawater does not hinder the adsorption of uranium.« less

  2. Effect of soil acidity, soil strength and macropores on root growth and morphology of perennial grass species differing in acid-soil resistance.

    PubMed

    Haling, Rebecca E; Simpson, Richard J; Culvenor, Richard A; Lambers, Hans; Richardson, Alan E

    2011-03-01

    It is unclear whether roots of acid-soil resistant plants have significant advantages, compared with acid-soil sensitive genotypes, when growing in high-strength, acid soils or in acid soils where macropores may allow the effects of soil acidity and strength to be avoided. The responses of root growth and morphology to soil acidity, soil strength and macropores by seedlings of five perennial grass genotypes differing in acid-soil resistance were determined, and the interaction of soil acidity and strength for growth and morphology of roots was investigated. Soil acidity and strength altered root length and architecture, root hair development, and deformed the root tip, especially in acid-soil sensitive genotypes. Root length was restricted to some extent by soil acidity in all genotypes, but the adverse impact of soil acidity on root growth by acid-soil resistant genotypes was greater at high levels of soil strength. Roots reacted to soil acidity when growing in macropores, but elongation through high-strength soil was improved. Soil strength can confound the effect of acidity on root growth, with the sensitivity of acid-resistant genotypes being greater in high-strength soils. This highlights the need to select for genotypes that resist both acidity and high soil strength. © 2010 Blackwell Publishing Ltd.

  3. Hierarchical 3D ordered meso-/macroporous metal-organic framework produced through a facile template-free self-assembly

    NASA Astrophysics Data System (ADS)

    Yang, Xiaoli; Wu, Suilan; Wang, Panhao; Yang, Lin

    2018-02-01

    The synthesis of well-ordered hierarchical metal-organic frameworks (MOFs) in an efficient manner is a great challenge. Here, a 3D regular ordered meso-/macroporous MOF of Cu-TATAB (referred to as MM-MOF) was synthesized through a facile template-free self-assembly process with pore sizes of 31 nm and 119 nm.

  4. Separation and purification of both tea seed polysaccharide and saponin from camellia cake extract using macroporous resin.

    PubMed

    Yang, Pengjie; Zhou, Mingda; Zhou, Chengyun; Wang, Qian; Zhang, Fangfang; Chen, Jian

    2015-02-01

    A novel method to separate and purify tea seed polysaccharide and tea seed saponin from camellia cake extract by macroporous resin was developed. Among four kinds of resins (AB-8, NKA-9, XDA-6, and D4020) tested, AB-8 macroporous resin possessed optimal separating capacity for the two substances and thus was selected for the separation, in which deionized water was used to elute tea seed polysaccharide, 0.25% NaOH solution to remove the undesired pigments, and 90% ethanol to elute tea seed saponin. Further dynamic adsorption/desorption experiments on AB-8 resin-based column chromatography were conducted to obtain the optimal parameters. Under optimal dynamic adsorption and desorption conditions, 18.7 and 11.8% yield of tea seed polysaccharide and tea seed saponin were obtained with purities of 89.2 and 96.0%, respectively. The developed method provides a potential approach for the large-scale production of tea seed polysaccharide and tea seed saponin from camellia cake. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Aligned macroporous TiO2/chitosan/reduced graphene oxide (rGO) composites for photocatalytic applications

    NASA Astrophysics Data System (ADS)

    Chen, Chao; Zhang, Yan; Zeng, Jing; Zhang, Fuqiang; Zhou, Kechao; Bowen, Chris R.; Zhang, Dou

    2017-12-01

    In this article ice templating is used to fabricate novel TiO2/chitosan/reduced graphene oxide (rGO) composites with a highly aligned macroporous structure for photocatalytic applications. The structure of the composites was readily tailored using the composite composition, for example the lamellar pore width decreased from 50-45 to 5-10 μm, while the lamellar thickness increased from 2-3 to 20-25 μm, with an increase of the TiO2 content from 45 to 77 vol%. Lamellar pore channels between the layers exhibited a more uniform distribution when the rGO content was 1.0 wt%. The increase in viscosity of the composites with high TiO2 contents led to the formation of smaller ice crystals and smaller lamellar pore sizes to enable the production of composite structures with improved mechanical strength. The TiO2/chitosan/rGO composites exhibited excellent photocatalytic degradation of methyl orange and the photocatalytic efficiency was optimized by control of the active material content and microstructure. The hybrid composites with 1.0 wt% rGO showed a degradation percentage of 97%, which makes these novel TiO2/chitosan/rGO freeze cast structures attractive materials as high performance and high strength substrates for photocatalytic degradation applications.

  6. Cholesterol-imprinted macroporous monoliths: Preparation and characterization.

    PubMed

    Stepanova, Mariia А; Kinziabulatova, Lilia R; Nikitina, Anna A; Korzhikova-Vlakh, Evgenia G; Tennikova, Tatiana B

    2017-11-01

    The development of sorbents for selective binding of cholesterol, which is a risk factor for cardiovascular disease, has a great importance for analytical science and medicine. In this work, two series of macroporous cholesterol-imprinted monolithic sorbents differing in the composition of functional monomers (methacrylic acid, butyl methacrylate, 2-hydroxyethyl methacrylate and ethylene dimethacrylate), amount of a template (4, 6 and 8 mol%) used for molecular imprinting, as well as mean pore size were synthesized by in situ free-radical process in stainless steel housing of 50 mm × 4.6 mm i.d. All prepared materials were characterized regarding to their hydrodynamic permeability and porous properties, as well as examined by BET and SEM methods. Imprinting factors, apparent dynamic dissociation constants, the maximum binding capacity, the number of theoretical plates and the height equivalent to a theoretical palate of MIP monoliths at different mobile phase flow rates were determined. The separation of a mixture of structural analogues, namely, cholesterol and prednisolone, was demonstrated. Additionally, the possibility of using the developed monoliths for cholesterol solid-phase extraction from simulated biological solution was shown. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Understanding Nanoemulsion Formation and Developing a Procedure for Porous Material Growth using Assembled Nanoemulsions

    NASA Astrophysics Data System (ADS)

    Yeranossian, Vahagn Frounzig

    Nanoemulsions as an emerging technology have found many applications in consumer products, drug delivery, and even particle formation. However, knowledge gaps exist in how some of these emulsions are formed, specifically what pathways are traversed to reach the final state. Moreover, how these pathways affect the final properties of the nanoemulsions would affect the applications that these droplets possess. Some nanoemulsions possess unique properties, including the assembly of droplets. While the assembly of droplets is being studied in the Helgeson lab, work must be done to understand how the assembly itself could be used to control the growth of porous materials, such a hydrogels. Thus, this thesis aims to address two factors of nanoemulsions: the formation of water-in-oil nanoemulsions and the use of assemblying droplets in oil-in-water nanoemulsions to form macroporous hydrogels. To elucidate the formation mechanism of water-in-oil nanoemulsions, a combination of dynamic light scattering and small angle neutron scattering were used to study the intermediate and final states of the nanoemulsion during its formation. These nanoemulsions were prepared by slowly adding water to an oil and surfactant mixture and were diluted to effectively measure using scattering techniques without multiple scattering events. To develop a procedure to use assembled nanoemulsions for the growth of porous materials, a combination of optical microscopy and diffusional studies were employed. Optical microscopy images taken at various stages of the procedure help elucidate how the pore sizes of the final porous material is related to the droplet-rich domains of the assembled nanoemulsion. Meanwhile, diffusional measurements help confirm the size and interconnectedness of the macropores. From the work done in the completion of my thesis, the formation mechanism of the water-in-oil nanoemulsion studied has been elucidated. The neutron scattering measurements show that during the

  8. Three-Dimensional Ordered Macroporous FePO4 as High-Efficiency Catalyst for Rechargeable Li-O2 Batteries.

    PubMed

    Li, Chao; Guo, Ziyang; Pang, Ying; Sun, Yunhe; Su, Xiuli; Wang, Yonggang; Xia, Yongyao

    2016-11-23

    The Li-O 2 battery is receiving much recent attention because of its superhigh theoretical energy density. However, its performance is limited by the irreversible formation/decomposition of Li 2 O 2 on the cathode and the undesired electrolyte decomposition. In this work, low-cost three-dimensional ordered macroporous (3DOM) FePO 4 is synthesized by using polystyrene (PS) spheres template in a facile experimental condition and applied as a high-efficiency catalyst for rechargeable Li-O 2 batteries, including good rate performance, high specific capacity, and perfect cycling stability. The superior performances can be attributed to the unique structure of 3DOM FePO 4 cathodes, which can provide an efficient buffer space for O 2 /Li 2 O 2 conversion. In addition, it is demonstrated that the Li + intercalation/deintercalation behavior of 3DOM FePO 4 in ether-based electrolyte can contribute to capacity for Li-O 2 batteries over cycling. As a result, when there is no O 2 in the environment, the Li-O 2 cell can also be operated as a rechargeable Li-FePO 4 cell with a perfect cycle capability.

  9. Bacteria-Affinity 3D Macroporous Graphene/MWCNTs/Fe3O4 Foams for High-Performance Microbial Fuel Cells.

    PubMed

    Song, Rong-Bin; Zhao, Cui-E; Jiang, Li-Ping; Abdel-Halim, Essam Sayed; Zhang, Jian-Rong; Zhu, Jun-Jie

    2016-06-29

    Promoting the performance of microbial fuel cells (MFCs) relies heavily on the structure design and composition tailoring of electrode materials. In this work, three-dimensional (3D) macroporous graphene foams incorporated with intercalated spacer of multiwalled carbon nanotubes (MWCNTs) and bacterial anchor of Fe3O4 nanospheres (named as G/MWCNTs/Fe3O4 foams) were first synthesized and used as anodes for Shewanella-inoculated microbial fuel cells (MFCs). Thanks to the macroporous structure of 3D graphene foams, the expanded electrode surface by MWCNTs spacing, as well as the high affinity of Fe3O4 nanospheres toward Shewanella oneidensis MR-1, the anode exhibited high bacterial loading capability. In addition to spacing graphene nanosheets for accommodating bacterial cells, MWCNTs paved a smoother way for electron transport in the electrode substrate of MFCs. Meanwhile, the embedded bioaffinity Fe3O4 nanospheres capable of preserving the bacterial metabolic activity provided guarantee for the long-term durability of the MFCs. With these merits, the constructed MFC possessed significantly higher power output and stronger stability than that with conventional graphite rod anode.

  10. The efficiency of macroporous polystyrene ion-exchange resins in natural organic matter removal from surface water

    NASA Astrophysics Data System (ADS)

    Urbanowska, Agnieszka; Kabsch-Korbutowicz, Małgorzata

    2017-11-01

    Natural water sources used for water treatment contains various organic and inorganic compounds. Surface waters are commonly contaminated with natural organic matter (NOM). NOM removal from water is important e.g. due to lowering the risk of disinfection by-product formation during chlorination. Ion exchange with the use of synthetic ion-exchange resins is an alternative process to typical NOM removal approach (e.g. coagulation, adsorption or oxidation) as most NOM compounds have anionic character. Moreover, neutral fraction could be removed from water due to its adsorption on resin surface. In this study, applicability of two macroporous, polystyrene ion exchange resins (BD400FD and A100) in NOM removal from water was assessed including comparison of treatment efficiency in various process set-ups and conditions. Moreover, resin regeneration effectivity was determined. Obtained results shown that examined resins could be applied in NOM removal and it should be noticed that column set-up yielded better results (contrary to batch set-up). Among the examined resins A100 one possessed better properties. It was determined that increase of solution pH resulted in a slight decrease in treatment efficiency while higher temperature improved it. It was also observed that regeneration efficiency was comparable in both tested methods but batch set-up required less reagents.

  11. NMR imaging of fluid exchange between macropores and matrix in eogenetic karst

    USGS Publications Warehouse

    Florea, L.J.; Cunningham, K.J.; Altobelli, S.

    2009-01-01

    Sequential time-step images acquired using nuclear magnetic resonance (NMR) show the displacement of deuterated water (D2O) by fresh water within two limestone samples characterized by a porous and permeable limestone matrix of peloids and ooids. These samples were selected because they have a macropore system representative of some parts of the eogenetic karst limestone of the Biscayne Aquifer in southeastern Florida. The macroporosity, created by the trace fossil Ophiomorpha, is principally well connected and of centimeter scale. These macropores occur in broadly continuous stratiform zones that create preferential flow layers within the hydrogeologic units of the Biscayne. This arrangement of porosity is important because in coastal areas, it could produce a preferential pathway for salt water intrusion. Two experiments were conducted in which samples saturated with D2O were placed in acrylic chambers filled with fresh water and examined with NMR. Results reveal a substantial flux of fresh water into the matrix porosity with a simultaneous loss of D 2O. Specifically, we measured rates upward of 0.001 mL/h/g of sample in static conditions, and perhaps as great as 0.07 mL/h/g of sample when fresh water continuously flows past a sample at velocities less than those found within stressed areas of the Biscayne. These experiments illustrate how fresh water and D2O, with different chemical properties, migrate within one type of matrix porosity found in the Biscayne. Furthermore, these experiments are a comparative exercise in the displacement of sea water by fresh water in the matrix of a coastal, karst aquifer since D2O has a greater density than fresh water. ?? 2008 National Ground Water Association.

  12. Cryogelation of molecularly imprinted nanoparticles: a macroporous structure as affinity chromatography column for removal of β-blockers from complex samples.

    PubMed

    Hajizadeh, Solmaz; Xu, Changgang; Kirsebom, Harald; Ye, Lei; Mattiasson, Bo

    2013-01-25

    In this work, a new macroporous molecularly imprinted cryogel (MIP composite cryogel) was synthesized by glutaraldehyde cross-linking reaction of poly(vinyl alcohol) (PVA) particles and amino-modified molecularly imprinted core-shell nanoparticles. The MIP core-shell nanoparticles were prepared using propranolol as a template by one-pot precipitation polymerization with sequential monomer addition. The characteristics of the MIP composite cryogel were studied by scanning electron microscopy (SEM) and texture analyzer. The macroporous structure of the composite (with the pore size varying from a few micrometers to 100 μm) enabled high mass transfer of particulate-containing fluids. In a solid phase extraction (SPE) process, the efficiency and selectivity of the MIP composite cryogel were investigated, where the cryogel was used as an affinity matrix to remove propranolol from aqueous solution as well as from complex plasma sample without prior protein precipitation. The MIP composite cryogel maintained high selectivity and stability and could be used repeatedly after regeneration. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Purification of bioactive phenolics from Phanerochaete chysosporium biomass extract on selected macroporous resins

    NASA Astrophysics Data System (ADS)

    Idris, Z. M.; Dzahir, M. I. H. M.; Jamal, P.; Barkat, A. A.; Xian, R. L. W.

    2017-06-01

    In this study, two different types of macroporous resins known as XAD-7HP and HP-20 were evaluated for the adsorption and desorption properties against bioactive phenolics extracted from Phanerochaete chrysosporium. From the previous static sorption studies, it was found that the adsorption capacity for both resins had has no significant difference. Then, the kinetic adsorption data were analyzed with both pseudo-first-order and pseudo-second-order equations and the later performed better. The adsorption isotherm data were fitted well by both Langmuir and Freundlich models. Meanwhile in desorption study, HP-20 and XAD-7HP gave 90.52% and 88.28% recoveries, respectively. Considering the desorption results of the macroporous resins, HP-20 and XAD-7HP were packed in chromatography column to further purify the phenolics. For dynamic adsorption, breakthrough capacity of HP-20 (0.522) was found to be higher than XAD-7HP (0.131). Different ethanol concentrations (30% to 50% (v/v)) were investigated at fixed flowrate (1 ml/min) on phenolics recovery from both types of resins. The highest recovery of bioactive phenolics was 94.3% using XAD-7HP resins at 50% (v/v) of ethanol. Only 77.1% of bioactive phenolics were recovered using HP-20 resin at the same experimental conditions. The purified extract subsequently was analyzed using HPLC. The results showed that three phenolics (gallic acid 3,4-dihydroxybenzoic acid and 4-hydroxybenzoic acid) were identified with higher concentrations as compared to non-purified extract. Finally, the purified extract was tested for scavenging activity against DPPH, and it showed that the activity increased significantly to 90.80% from 59.94% in non-purified extract.

  14. Design, fabrication, and testing of three-dimensionally ordered macroporous materials for pseudomorphic transformation and power storage

    NASA Astrophysics Data System (ADS)

    Lytle, Justin Conrad

    This dissertation details my study of three-dimensionally ordered macroporous (3DOM) materials, which were prepared using polymer latex colloidal crystal templates. These solids are composed of close-packed and three-dimensionally interconnected spherical macropores surrounded by nanoscale solid wall skeletons. This unique architecture offers relatively large surface areas that are accessible by interconnected macropores, making these materials important for innovative catalysis, sensing, and separations applications. In addition, the three-dimensionally alternating dielectric structure can establish photonic stop bands that control the flow of light analogously to the restraint of electronic conduction by electronic bandgaps. Many potential applications would benefit from reducing device feature sizes from the bulk into the nanoscale regime. However, some compositions are more easily prepared as nanostructured materials than others. Therefore, it would be immensely important to develop synthetic methods of transforming solids that are more easily formed with nanoarchitectural features into compositions that are not. Pseudomorphic transformation reactions may be one solution to this problem, since they are capable of altering chemical composition while maintaining shape and structural morphology. Several compositions of inverse opal and nanostructured preforms were investigated in this work to study the effects of vapor-phase and solution-phase conversion reactions on materials with feature sizes ranging from a few nm to tens of mum. 3DOM SiO2 and WO3, nanostructured Ni, and colloidal silica sphere performs were studied to investigate the effects of preform chemistries, feature sizes and shapes, processing temperatures, and reagent ratios on overall pseudomorphic structural retention. Power storage and fuel cell devices based on nanostructured electrodes are a major example of how reducing device component feature sizes can greatly benefit applications. Bulk

  15. Imaginal Disc Abnormalities in Lethal Mutants of Drosophila

    PubMed Central

    Shearn, Allen; Rice, Thomas; Garen, Alan; Gehring, Walter

    1971-01-01

    Late lethal mutants of Drosophila melanogaster, dying after the larval stage of development, were isolated. The homozygous mutant larvae were examined for abnormal imaginal disc morphology, and the discs were injected into normal larval hosts to test their capacities to differentiate into adult structures. In about half of the mutants analyzed, disc abnormalities were found. Included among the abnormalities were missing discs, small discs incapable of differentiating, morphologically normal discs with limited capacities for differentiation, and discs with homeotic transformations. In some mutants all discs were affected, and in others only certain discs. The most extreme abnormal phenotype is a class of “discless” mutants. The viability of these mutant larvae indicates that the discs are essential only for the development of an adult and not of a larva. The late lethals are therefore a major source of mutants for studying the genetic control of disc formation. Images PMID:5002822

  16. Formation of Nanofibrous Matrices, Three-Dimensional Scaffolds, and Microspheres: From Theory to Practice

    PubMed Central

    Ma, Chi

    2017-01-01

    Nanofibrous architecture presents unique biophysical cues to facilitate cellular responses and is considered an indispensable feature of a biomimetic three-dimensional (3D) scaffold and cell carrier. While electrospinning is a widely used method to prepare natural extracellular matrix-like nanofibers, it faces significant challenges to incorporate nanofibrous architecture into well-defined macroporous 3D scaffolds or injectable microspheres. Here we report a nonelectrospinning approach that is effective at generating nanofibers from a variety of synthetic and natural biodegradable polymers and integrating these nanofibers into (1) 3D scaffolds with constructive geometry and designed internal macropore structures; and (2) injectable microspheres. Our approach to generating polymer nanofibers is based on the control of polymer–solvent interaction parameter χp-s. We obtained the χp-s and solvent composition phase diagrams of different temperatures according to the Flory–Huggins classic lattice model and the Hildebrand-Scott solubility parameter equation. A critical polymer–solvent interaction parameter χcrit was introduced as a criterion to predict phase separation and nanofiber formation. To test the effectiveness of our approach, a total of 15 widely used biodegradable polymers were selected and successfully fabricated into nanofibrous matrices. Furthermore, macroporous nanofibrous 3D scaffolds with complex architecture and nanofibrous injectable microspheres were generated from those biodegradable polymers by combining our method with other processes. Our approach is universally effective to fabricate nanofibrous matrices from any polymeric materials. This work, therefore, greatly expands our ability to design appropriate biomimetic 3D scaffolds and injectable cell carriers for advanced regenerative therapies. PMID:27923327

  17. Surface plasmon resonance sensor for femtomolar detection of testosterone with water-compatible macroporous molecularly imprinted film.

    PubMed

    Zhang, Qingwen; Jing, Lijing; Zhang, Jinling; Ren, Yamin; Wang, Yang; Wang, Yi; Wei, Tianxin; Liedberg, Bo

    2014-10-15

    A novel water-compatible macroporous molecularly imprinted film (MIF) has been developed for rapid, sensitive, and label-free detection of small molecule testosterone in urine. The MIF was synthesized by photo copolymerization of monomers (methacrylic acid [MAA] and 2-hydroxyethyl methacrylate [HEMA]), cross-linker (ethylene glycol dimethacrylate, EGDMA), and polystyrene nanoparticles (PS NPs) in combination with template testosterone molecules. The PS NPs and template molecules were subsequently removed to form an MIF with macroporous structures and the specific recognition sites of testosterone. Incubation of artificial urine and human urine on the MIF and the non-imprinted film (NIF), respectively, indicated undetectable nonspecific adsorption. Accordingly, the MIF was applied on a surface plasmon resonance (SPR) sensor for the detection of testosterone in phosphate-buffered saline (PBS) and artificial urine with a limit of detection (LOD) down to 10(-15)g/ml. To the best of our knowledge, the LOD is considered as one of the lowest among the SPR sensors for the detection of small molecules. The control experiments performed with analogue molecules such as progesterone and estradiol demonstrated the good selectivity of this MIF for sensing testosterone. Furthermore, this MIF-based SPR sensor shows high stability and reproducibility over 8months of storage at room temperature, which is more robust than protein-based biosensors. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Cell death in neural precursor cells and neurons before neurite formation prevents the emergence of abnormal neural structures in the Drosophila optic lobe.

    PubMed

    Hara, Yusuke; Sudo, Tatsuya; Togane, Yu; Akagawa, Hiromi; Tsujimura, Hidenobu

    2018-04-01

    Programmed cell death is a conserved strategy for neural development both in vertebrates and invertebrates and is recognized at various developmental stages in the brain from neurogenesis to adulthood. To understand the development of the central nervous system, it is essential to reveal not only molecular mechanisms but also the role of neural cell death (Pinto-Teixeira et al., 2016). To understand the role of cell death in neural development, we investigated the effect of inhibition of cell death on optic lobe development. Our data demonstrate that, in the optic lobe of Drosophila, cell death occurs in neural precursor cells and neurons before neurite formation and functions to prevent various developmental abnormalities. When neuronal cell death was inhibited by an effector caspase inhibitor, p35, multiple abnormal neuropil structures arose during optic lobe development-e.g., enlarged or fused neuropils, misrouted neurons and abnormal neurite lumps. Inhibition of cell death also induced morphogenetic defects in the lamina and medulla development-e.g., failures in the separation of the lamina and medulla cortices and the medulla rotation. These defects were reproduced in the mutant of an initiator caspase, dronc. If cell death was a mechanism for removing the abnormal neuropil structures, we would also expect to observe them in mutants defective for corpse clearance. However, they were not observed in these mutants. When dead cell-membranes were visualized with Apoliner, they were observed only in cortices and not in neuropils. These results suggest that the cell death occurs before mature neurite formation. Moreover, we found that inhibition of cell death induced ectopic neuroepithelial cells, neuroblasts and ganglion mother cells in late pupal stages, at sites where the outer and inner proliferation centers were located at earlier developmental stages. Caspase-3 activation was observed in the neuroepithelial cells and neuroblasts in the proliferation centers

  19. Role of macropore flow in the transport of Escherichia coli cells in undisturbed cores of a brown leached soil.

    PubMed

    Martins, Jean M F; Majdalani, Samer; Vitorge, Elsa; Desaunay, Aurélien; Navel, Aline; Guiné, Véronique; Daïan, Jean François; Vince, Erwann; Denis, Hervé; Gaudet, Jean Paul

    2013-02-01

    The objective of this work was to evaluate the transport of Escherichia coli cells in undisturbed cores of a brown leached soil collected at La Côte St André (France). Two undisturbed soil cores subjected to repeated injections of bacterial cells and/or bromide tracer were used to investigate the effect of soil hydrodynamics and ionic strength on cell mobility. Under the tested experimental conditions, E. coli cells were shown to be transported at the water velocity (retardation factor close to 1) and their retention appeared almost insensitive to water flow and ionic strength variations, both factors being known to control bacterial transport in model saturated porous media. In contrast, E. coli breakthrough curves evolved significantly along with the repetition of the cell injections in each soil core, with a progressive acceleration of their transport. The evolution of E. coli cells BTCs was shown to be due to the evolution of the structure of soil hydraulic pathways caused by the repeated water infiltrations and drainage as may occur in the field. This evolution was demonstrated through mercury intrusion porosimetry (MIP) performed on soil aggregates before and after the repeated infiltrations of bacteria. MIP revealed a progressive and important reduction of the soil aggregate porosity, n, that decreased from approximately 0.5 to 0.3, along with a decrease of the soil percolating step from 27 to 2 μm. From this result a clear compaction of soil aggregates was evidenced that concerned preferentially the pores larger than 2 μm equivalent diameter, i.e. those allowing bacterial cell passage. Since no significant reduction of the global soil volume was observed at the core scale, this aggregate compaction was accompanied by macropore formation that became progressively the preferential hydraulic pathway in the soil cores, leading to transiently bi-modal bacterial BTCs. The evolution of the soil pore structure induced a modification of the main hydrodynamic

  20. Friction Stir Welding of Al Alloy 2219-T8: Part I-Evolution of Precipitates and Formation of Abnormal Al2Cu Agglomerates

    NASA Astrophysics Data System (ADS)

    Kang, Ju; Feng, Zhi-Cao; Frankel, G. S.; Huang, I. Wen; Wang, Guo-Qing; Wu, Ai-Ping

    2016-09-01

    Friction stir welding was performed on AA2219-T8 plates with 6.31 wt pct Cu. The thermal cycles were measured in different regions of the joint during welding. Differential scanning calorimetry and transmission electron microscopy were utilized to analyze the evolution of precipitates in the joint. The relationships between welding peak temperature, precipitate evolution, and microhardness distribution are discussed. The temperature in the heat-affected zone (HAZ) ranged from 453 K to 653 K (180 °C to 380 °C). The θ″ and some θ' phases redissolved into the HAZ matrix, while the rest of the θ' phases coarsened. In the thermomechanically affected zone (TMAZ), the temperature range was from 653 K to 673 K (380 °C to 400 °C), causing both θ″ phase and θ' phase to redissolve. In the weld nugget zone (WNZ), all the θ″, θ', and some of the θ phase (Al2Cu) redissolved. Abnormal θ particles were observed in the WNZ, including agglomerated θ with sizes around 100 to 1000 µm and a ring-shaped distribution of normal size θ particles. The formation of abnormal θ particles resulted from metal plastic flow during welding and the high content of Cu in AA2219. No abnormal θ particles were observed in joints of another AA2219 plate, which had a lower Cu content of 5.83 wt pct.

  1. Macroporous biohybrid cryogels for co-housing pancreatic islets with mesenchymal stromal cells.

    PubMed

    Borg, Danielle J; Welzel, Petra B; Grimmer, Milauscha; Friedrichs, Jens; Weigelt, Marc; Wilhelm, Carmen; Prewitz, Marina; Stißel, Aline; Hommel, Angela; Kurth, Thomas; Freudenberg, Uwe; Bonifacio, Ezio; Werner, Carsten

    2016-10-15

    Intrahepatic transplantation of allogeneic pancreatic islets offers a promising therapy for type 1 diabetes. However, long-term insulin independency is often not achieved due to severe islet loss shortly after transplantation. To improve islet survival and function, extrahepatic biomaterial-assisted transplantation of pancreatic islets to alternative sites has been suggested. Herein, we present macroporous, star-shaped poly(ethylene glycol) (starPEG)-heparin cryogel scaffolds, covalently modified with adhesion peptides, for the housing of pancreatic islets in three-dimensional (3D) co-culture with adherent mesenchymal stromal cells (MSC) as accessory cells. The implantable biohybrid scaffolds provide efficient transport properties, mechanical protection, and a supportive extracellular environment as a desirable niche for the islets. MSC colonized the cryogel scaffolds and produced extracellular matrix proteins that are important components of the natural islet microenvironment known to facilitate matrix-cell interactions and to prevent cellular stress. Islets survived the seeding procedure into the cryogel scaffolds and secreted insulin after glucose stimulation in vitro. In a rodent model, intact islets and MSC could be visualized within the scaffolds seven days after subcutaneous transplantation. Overall, this demonstrates the potential of customized macroporous starPEG-heparin cryogel scaffolds in combination with MSC to serve as a multifunctional islet supportive carrier for transplantation applications. Diabetes results in the insufficient production of insulin by the pancreatic β-cells in the islets of Langerhans. Transplantation of pancreatic islets offers valuable options for treating the disease; however, many transplanted islets often do not survive the transplantation or die shortly thereafter. Co-transplanted, supporting cells and biomaterials can be instrumental for improving islet survival, function and protection from the immune system. In the

  2. Adsorption and desorption properties of macroporous resins for anthocyanins from the calyx extract of roselle (Hibiscus sabdariffa L.).

    PubMed

    Chang, Xiu-Lian; Wang, Dong; Chen, Bi-Yun; Feng, Yong-Mei; Wen, Shao-Hong; Zhan, Peng-Yuan

    2012-03-07

    Adsorption of roselle anthocynins, a natural pigment, onto various macroporous resins was optimized to develop a simple and efficient process for industrial separation and purification of roselle anthocyanins. Nine different macroporous resins (AB-8, X-5, HPD-100, SP-207, XAD-4, LS-305A, DM-21, LS-610B, and LS-305) were evaluated for the adsorption properties of the anthocyanins extracted from the calyx extract of Hibiscus sabdariffa L. The influences of phase contact time, solution pH, initial anthocyanin concentration, and ethanol concentration with different citric acid amounts were studied by the static adsorption/desorption method. The adsorption isotherm data were fitted well to the Langmuir isotherm, and according to this model, LS-610B and LS-305 exhibited the highest monolayer sorption capacities of 31.95 and 38.16 mg/g, respectively. The kinetic data were modeled using pseudo-first-order, pseudo-second-order, and intraparticle diffusion equations. The experimental data were well described by the pseudo-second-order kinetic model. Continuous column adsorption-regeneration cycles indicated negligible capacity loss of LS-305 during operation. The overall yield of pigment product was 49.6 mg/g dried calyces. The content of roselle anthocynins in the pigment product was 4.85%.

  3. Qualitative Analysis of Polyphenols in Macroporous Resin Pretreated Pomegranate Husk Extract by HPLC-QTOF-MS.

    PubMed

    Abdulla, Rahima; Mansur, Sanawar; Lai, Haizhong; Ubul, Ablikim; Sun, Guangying; Huang, Guozheng; Aisa, Haji Akber

    2017-09-01

    Pomegranate (Punica granatum L.) husk is a traditional herbal medicine abundant in phenolic compounds and plays some roles in the treatment of oxidative stress, bacterial and viral infection, diabetes mellitus, and acute and chronic inflammation. Identification and determination of polyphenols in macroporous resin pretreated pomegranate husk extract by high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF-MS). The total polyphenols of pomegranate husk were prepared by ethanol extraction followed by pretreatment with HPD-300 macroporous resin. The polyphenolic compounds were qualitatively analysed by HPLC-QTOF-MS in negative electrospray ionisation (ESI) mode at different collision energy (CE) values. A total of 50 polyphenols were detected in the extract of pomegranate husk, including 35 hydrolysable tannins and 15 flavonoids with distinct retention time, fragmentation behaviours and characteristics, and the accurate mass-to-charge ratios at low, moderate and high CE values. Of these, we identified nine compounds for the first time in the pomegranate husk, including hexahydroxydiphenoyl-valoneoyl-glucoside (HHDP-valoneyl-glucoside), galloyl-O-punicalin, rutin, hyperoside, quercimeritrin, kaempferol-7-O-rhahmano-glucoside, luteolin-3'-O-arabinoside, luteolin-3'-O-glucoside, and luteolin-4'-O-glucoside. To validate the specificity and accuracy of mass spectrometry in the detection of polyphenols, as compared to the fragmentation pathways of granatin B in detail, including the HHDP-valoneyl- glucoside was first identified from pomegranate husk. The study provides evidence for the quality control and development of novel drugs based on polyphenols from the pomegranate husk. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  4. Crab-shell induced synthesis of ordered macroporous carbon nanofiber arrays coupled with MnCo2O4 nanoparticles as bifunctional oxygen catalysts for rechargeable Zn-air batteries.

    PubMed

    Bin, Duan; Guo, Ziyang; Tamirat, Andebet Gedamu; Ma, Yuanyuan; Wang, Yonggang; Xia, Yongyao

    2017-08-10

    The oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are traditionally carried out using noble metals (such as Pt) and metal oxides (such as RuO 2 and IrO 2 ) as catalysts, respectively. Nevertheless, several key issues such as high cost, poor stability, and detrimental environmental effects limit the catalytic activity of these noble metal- and metal oxide-based catalysts. Herein, we have designed and synthesized macroporous carbon nanofiber arrays by using a natural crab shell template. Subsequently, spinel MnCo 2 O 4 nanoparticles were embedded into the nitrogen-doped macroporous carbon nanofiber arrays (NMCNAs) by a hydrothermal method. Accompanied by the good conductivity, large surface area and doping of nitrogen, the as-prepared MnCo 2 O 4 /NMCNA exhibited remarkable catalytic performance and outstanding stability for both ORR and OER in alkaline media. The macroporous superstructures play vital role in reducing the ion transport resistance and facilitating the diffusion of gaseous products (O 2 ). Finally, rechargeable Zn-air batteries using the MnCo 2 O 4 /NMCNA catalyst displayed appreciably lower overpotentials, higher power density and better stability than commercial Pt/C, thus raising the prospect of functional low-cost, non-precious-metal bifunctional catalysts in metal-air batteries.

  5. Abnormal pressure study in the Malay and Penyu Basins: A regional understanding

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

    Kader, M.S.; Leslie, W.

    1994-07-01

    A majority of wells drilled in the Malay and Penyu basins were terminated due to abnormal pressure. Blowouts and the subsequent loss of technical data have always been a concern during drilling operations. This study employs data from 94 exploratory wells spread throughout the Malay and Penyu basins. The postdrill abnormal pressure predictive method used is pressure vs. depth plots of data obtained from Repeat Formation tester (RFT) readings. The study results indicate that abnormal pressure occurs in a progressively older stratigraphic unit toward the basin margins. The margins of the Malay and the entire Penyu basins tend to bemore » normally pressured. The onset of abnormal pressure appears to be abrupt in the northern portion and more gradual in the southern part of the Malay Basin. Abnormal pressure in the Malay Basin is found to be neither depth dependent nor age related. Many factors can cause the abnormal formation pressures. In some areas, a combination of factors prevails. Rapid deposition of the middle to late Miocene siliciclastic sediments appears to be a dominant cause particularly in the center of the Malay Basin. A low sand:shale ratio coupled with a high geothermal gradient is also found to be a local cause near the axis of the basin. This phenomenon is crucial to the understanding of hydrocarbon migration and will enable the planning of safe and efficient drilling campaigns.« less

  6. Hierarchically Macroporous Graphitic Nanowebs Exhibiting Ultra-fast and Stable Charge Storage Performance

    NASA Astrophysics Data System (ADS)

    Yun, Young Soo

    2018-02-01

    The macro/microstructures of carbon-based electrode materials for supercapacitor applications play a key role in their electrochemical performance. In this study, hierarchically macroporous graphitic nanowebs (HM-GNWs) were prepared from bacterial cellulose by high-temperature heating at 2400 °C. The HM-GNWs were composed of well-developed graphitic nanobuilding blocks with a high aspect ratio, which was entangled as a nanoweb structure. The morphological and microstructural characteristics of the HM-GNWs resulted in remarkable charge storage performance. In particular, the HM-GNWs exhibited very fast charge storage behaviors at scan rates ranging from 5 to 100 V s-1, in which area capacitances ranging from 8.9 to 3.8 mF cm-2 were achieved. In addition, 97% capacitance retention was observed after long-term cycling for more than 1,000,000 cycles.

  7. Isolation of organic acids from large volumes of water by adsorption on macroporous resins

    USGS Publications Warehouse

    Aiken, George R.; Suffet, I.H.; Malaiyandi, Murugan

    1987-01-01

    Adsorption on synthetic macroporous resins, such as the Amberlite XAD series and Duolite A-7, is routinely used to isolate and concentrate organic acids from forge volumes of water. Samples as large as 24,500 L have been processed on site by using these resins. Two established extraction schemes using XAD-8 and Duolite A-7 resins are described. The choice of the appropriate resin and extraction scheme is dependent on the organic solutes of interest. The factors that affect resin performance, selectivity, and capacity for a particular solute are solution pH, resin surface area and pore size, and resin composition. The logistical problems of sample handling, filtration, and preservation are also discussed.

  8. Mechanosensation across borders: fibroblasts inside a macroporous scaffold sense and respond to the mechanical environment beyond the scaffold walls.

    PubMed

    Könnig, D; Herrera, A; Duda, G N; Petersen, A

    2018-01-01

    In tissue defects, cells face distinct mechanical boundary conditions, but how this influences early stages of tissue regeneration remains largely unknown. Biomaterials are used to fill defects but also to provide specific mechanical or geometrical signals. However, they might at the same time shield mechanical information from surrounding tissues that is relevant for tissue functionalisation. This study investigated how fibroblasts in a soft macroporous biomaterial scaffold respond to distinct mechanical environments while they form microtissues. Different boundary stiffnesses counteracting scaffold contraction were provided via a newly developed in vitro setup. Online monitoring over 14 days revealed 3.0 times lower microtissue contraction but 1.6 times higher contraction force for high vs. low stiffness. This difference was significant already after 48 h, a very early stage of microtissue growth. The microtissue's mechanical and geometrical adaptation indicated a collective cellular behaviour and mechanical communication across scaffold pore walls. Surprisingly, the stiffness of the environment influenced cell behaviour even inside macroporous scaffolds where direct cell-cell contacts are hindered. Mechanical communication between cells via traction forces is essential for tissue adaptation to the environment and should not be blocked by rigid biomaterials. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  9. Aqueous cholesteric liquid crystals using uncharged rodlike polypeptides. Polypeptide vesicles by conformation-specific assembly. Ordered chiral macroporous hybrid silica-polypeptide composites

    NASA Astrophysics Data System (ADS)

    Bellomo, Enrico Giuseppe

    2005-07-01

    Aqueous cholesteric liquid crystals using uncharged rodlike polypeptides . The aqueous, lyotropic liquid-crystalline phase behavior of an alpha helical polypeptide, has been studied using optical microscopy and X-ray scattering. Solutions of optically pure polypeptide were found to form cholesteric liquid crystals at volume fractions that decreased with increasing average chain length. At very high volume fractions, the formation of a hexagonal mesophase was observed. The pitch of the cholesteric phase could be varied by a mixture of enantiomeric samples, where the pitch increased as the mixture approached equimolar. The cholesteric phases could be untwisted, using either magnetic field or shear flow, into nematic phases, which relaxed into cholesterics upon removal of field or shear. We have found that the phase diagram of this polypeptide in aqueous solution parallels that of poly(gamma-benzyl glutamate) in organic solvents, thus providing a useful system for liquid-crystal applications requiring water as solvent. Polypeptide vesicles by conformation-specific assembly. We have found that block copolymers composed of polypeptide segments provide significant advantages in controlling both the function and supramolecular structure of bioinspired self-assemblies. Incorporation of the stable chain conformations found in proteins into block copolymers was found to provide an additional element of control, beyond amphiphilicity and composition that defines self-assembled architecture. The abundance of functionality present in amino acids, and the ease by which they can be incorporated into these materials, also provides a powerful mechanism to impart block copolypeptides with function. This combination of structure and function work synergistically to enable significant advantages in the preparation of therapeutic agents as well as provide insight into design of self-assemblies beginning to approach the complexity of natural structures such as virus capsids. Ordered

  10. Facile synthesis of flexible macroporous polypropylene sponges for separation of oil and water

    PubMed Central

    Wang, Guowei; Uyama, Hiroshi

    2016-01-01

    Oil spill disasters always occur accidentally, accompanied by the release of plenty of crude oil that could spread quickly over a wide area, creating enormous damage to the fragile marine ecological system. Therefore, the facile large-scale synthesis of hydrophobic three-dimensional (3-D) porous sorbents from low cost raw materials is in urgent demand. In this study, we report the facile template-free synthesis of polypropylene (PP) sponge by using a thermally-induced phase separation (TIPS) technique. The obtained sponge showed macroporous structure, excellent mechanical property, high hydrophobicity, and superoleophilicity. Oil could be separated from an oil/water mixture by simple immersing the sponge into the mixture and subsequent squeezing the sponge. All of these features make this sponge the most promising oil sorbent that will replace commercial non-woven PP fabrics. PMID:26880297

  11. Structural transformation of macroporous silicon anodes as a result of cyclic lithiation processes

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

    Li, G. V.; Kulova, T. L.; Tolmachev, V. A., E-mail: tva@mail.ioffe.ru

    2013-09-15

    Anodes based on a regular lattice of macroporous silicon with different periods, sizes, and shapes of pore cross sections are studied. The discharge capacity and its degradation during cycling (embedding and extraction of lithium) are examined. Scanning electron microscopy is used to analyze changes in the electrode structure upon the lithiation/delithiation of Si and to evaluate the elemental composition of the porous material. An ex situ morphological analysis of the electrodes demonstrates that, on the whole, the porous structure is preserved upon cycling and the thickness of silicon walls increases. The degree of Si-wall destruction depends on their initial thickness.more » Estimates show that the electrolyte reduction process mainly occurs according to the two-electron mechanism, with inorganic salts of lithium formed as a result.« less

  12. Significantly enhanced energy output from 3D ordered macroporous structured Fe2O3/Al nanothermite film.

    PubMed

    Zhang, Wenchao; Yin, Baoqing; Shen, Ruiqi; Ye, Jiahai; Thomas, Jason A; Chao, Yimin

    2013-01-23

    A three-dimensionally ordered macroporous Fe(2)O(3)/Al nanothermite membrane has been prepared with a polystyrene spheres template. The nanothermite, with an enhanced interfacial contact between fuel and oxidizer, outputs 2.83 kJ g(-1) of energy. This is significantly more than has been reported before. This approach, fully compatible with MEMS technology, provides an efficient way to produce micrometer thick three-dimensionally ordered nanostructured thermite films with overall spatial uniformity. These exciting achievements will greatly facilitate potential for the future development of applications of nanothermites.

  13. Adsorption kinetics, isotherm, and thermodynamics studies of acetyl-11-keto-β-boswellic acids (AKBA) from Boswellia serrata extract using macroporous resin.

    PubMed

    Niphadkar, Sonali S; Rathod, Virendra K

    2017-09-14

    An acetyl-11-keto-β-boswellic acid (AKBA) is potent anti-inflammatory agent found in Boswellia serrata oleogum resin. Adsorption characteristics of AKBA from B. serrata were studied using macroporous adsorbent resin to understand separation and adsorption mechanism of targeted molecules. Different macroporous resins were screened for adsorption and desorption of AKBA and Indion 830 was screened as it showed higher adsorption capacity. The kinetic equations were studied and results showed that the adsorption of AKBA on Indion 830 was well fitted to the pseudo first-order kinetic model. The influence of two parameters such as temperature (298, 303, and 308 K) and pH (5-8) on the adsorption process was also studied. The experimental data was further investigated using Langmuir, Freundlich, and Temkin isotherm models. It was observed that Langmuir isotherm model was found to be the best fit for AKBA adsorption by Indion 830 and highest adsorption capacity (50.34 mg/g) was obtained at temperature of 303 K. The values of thermodynamic parameters such as the change of Gibbs free energy (ΔG*), entropy (ΔS*), and enthalpy (ΔH*), indicated that the process of adsorption was spontaneous, favourable, and exothermic.

  14. A multi-scaled hybrid orthopedic implant: bone ECM-shaped Sr-HA nanofibers on the microporous walls of a macroporous titanium scaffold.

    PubMed

    Han, Yong; Zhou, Jianhong; Zhang, Lan; Xu, Kewei

    2011-07-08

    We report here, for the first time, a novel multi-scaled hybrid orthopedic implant material consisting of a macroporous Ti scaffold, whose macropores' walls have a microporous titania layer which is fully covered with nanofibers of Sr-doped hydroxyapatite (Sr-HA). The microporous titania layer is formed on and within the Ti scaffold by micro-arc oxidation, which firmly binds to the Ti substrate and contains Ca2+, Sr2+ and PO4(3-) ions. It is then hydrothermally treated to form Sr-HA nanofibers. During the hydrothermal treatment, Sr-HA nanoprisms nucleate from Ca0.5Sr0.5TiO3 pre-formed on the TiO2 and grow in length to nanofibers at the expense of Ca2+, Sr2+ and PO4(3-) ions that migrate from the TiO2. These Sr-HA nanofibers construct a network structure similar to the hierarchical organization of bone extracellular matrix (ECM), and the resulting nanofibrous surface displays a firm adhesion to substrate, superhydrophilicity and apatite-inducing ability. The induced apatite prefers to nucleate on the basal-faceted surfaces of Sr-HA nanofibers. The nanofiber-walled scaffold has a great potential for load-bearing orthotopic use.

  15. A multi-scaled hybrid orthopedic implant: bone ECM-shaped Sr-HA nanofibers on the microporous walls of a macroporous titanium scaffold

    NASA Astrophysics Data System (ADS)

    Han, Yong; Zhou, Jianhong; Zhang, Lan; Xu, Kewei

    2011-07-01

    We report here, for the first time, a novel multi-scaled hybrid orthopedic implant material consisting of a macroporous Ti scaffold, whose macropores' walls have a microporous titania layer which is fully covered with nanofibers of Sr-doped hydroxyapatite (Sr-HA). The microporous titania layer is formed on and within the Ti scaffold by micro-arc oxidation, which firmly binds to the Ti substrate and contains Ca2 + , Sr2 + and PO43 - ions. It is then hydrothermally treated to form Sr-HA nanofibers. During the hydrothermal treatment, Sr-HA nanoprisms nucleate from Ca0.5Sr0.5TiO3 pre-formed on the TiO2 and grow in length to nanofibers at the expense of Ca2 + , Sr2 + and PO43 - ions that migrate from the TiO2. These Sr-HA nanofibers construct a network structure similar to the hierarchical organization of bone extracellular matrix (ECM), and the resulting nanofibrous surface displays a firm adhesion to substrate, superhydrophilicity and apatite-inducing ability. The induced apatite prefers to nucleate on the basal-faceted surfaces of Sr-HA nanofibers. The nanofiber-walled scaffold has a great potential for load-bearing orthotopic use.

  16. Macroporous Carbon Supported Zerovalent Iron for Remediation of Trichloroethylene

    DOE PAGES

    Lawrinenko, Michael; Wang, Zhuangji; Horton, Robert; ...

    2016-12-26

    Groundwater contamination with chlorinated hydrocarbons has become a widespread problem that threatens water quality and human health. Permeable reactive barriers (PRBs), which employ zerovalent iron, are effective for remediation; however, a need exists to reduce the economic and environmental costs associated with constructing PRBs. Here, we present a method to produce zerovalent iron supported on macroporous carbon using only lignin and magnetite. Biochar- ZVI (BC-ZVI) produced by this method exhibits a broad pore size distribution with micrometer sized ZVI phases dispersed throughout a carbon matrix. X-ray diffraction revealed that pyrolysis at 900 °C of a 50/50 lignin$-$magnetite mixture resulted inmore » almost complete reduction of magnetite to ZVI and that compression molding promotes iron reduction in pyrolysis due to mixing of starting materials. High temperature pyrolysis of lignin yields some graphite in BC-ZVI due to reduction of carbonaceous gases on iron oxides. TCE was removed from water as it passed through a column packed with BC-ZVI at flow rates representative of average and high groundwater flow. Lastly, one-dimensional convection$-$dispersion modeling revealed that adsorption by biochar influences TCE transport and that BC-ZVI facilitated removal of TCE from contaminated water by both adsorption and degradation.« less

  17. Enrichment and purification of six Aconitum alkaloids from Aconiti kusnezoffii radix by macroporous resins and quantification by HPLC-MS.

    PubMed

    Liu, Jingjing; Li, Qing; Liu, Ran; Yin, Yidi; Chen, Xiaohui; Bi, Kaishun

    2014-06-01

    Aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine and benzoylhypaconine are six main Aconitum alkaloids from traditional Chinese medicine, Aconiti kusnezoffii radix, which possess highly bioactive as well as highly toxic character for medicinal use. In the present study, for the purpose of better utilizing the toxic herbal material, the performance characteristics of NKA-II, D101, X-5, AB-8, S-8, HPD722 and HPD750 macroporous resins for the enrichment and purification of these six Aconitum alkaloids were critically evaluated. Results showed that NKA-II offered the best adsorption and desorption capacities for six Aconitum alkaloids among the seven macroporous resins tested, which were affected significantly by the pH value. Subsequently, dynamic adsorption and desorption experiments had been carried out with the column packed by NKA-II resin to optimize the separation process of six Aconitum alkaloids. After one run treatment with NKA-II resin, the content of total six Aconitum alkaloids were increased from 5.87% to 60.3%, the recovery was 75.8%. Meanwhile, a validated HPLC-MS method had been developed to qualitative and quantitative these six Aconitum alkaloids. This method would provide scientific references to the large-scale production of six Aconitum alkaloids from Aconiti kusnezoffii radix or other plants and might also expand the secure application of these highly toxic components for pharmacy. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Separation and purification of epigallocatechin-3-gallate (EGCG) from green tea using combined macroporous resin and polyamide column chromatography.

    PubMed

    Jin, Xin; Liu, Mingyan; Chen, Zaixing; Mao, Ruikun; Xiao, Qinghuan; Gao, Hua; Wei, Minjie

    2015-10-01

    Epigallocatechin-3-gallate (EGCG) is a major bioactive ingredient of green tea that produces beneficial neuroprotective effects. In this paper, to optimize the EGCG enrichment, thirteen macroporous resins with different chemical and physical properties were systemically evaluated. Among the thirteen tested resins, the H-bond resin HPD826 exhibited best adsorption/desorption capabilities and desorption ratio, as well as weakest affinity for caffeine. The absorption of EGCG on the HPD826 resin followed the pseudo-second-order kinetics and Langmuir isotherm model. The separation parameters of EGCG were optimized by dynamic adsorption/desorption experiments with the HPD826 resin column. Under the optimal condition, the content of EGCG in the 30% ethanol eluent increased by 5.8-fold from 7.7% to 44.6%, with the recovery yield of 72.1%. After further purification on a polyamide column, EGCG with 74.8% purity was obtained in the 40-50% ethanol fraction with a recovery rate of 88.4%. In addition, EGCG with 95.1% purity could be easily obtained after one-step crystallization in distilled water. Our study suggests that the combined macroporous resin and polyamide column chromatography is a simple method for large-scale separation and purification of EGCG from natural plants for food and pharmaceutical applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. 3D-macroporous chitosan-based scaffolds with in situ formed Pd and Pt nanoparticles for nitrophenol reduction.

    PubMed

    Berillo, Dmitriy; Cundy, Andrew

    2018-07-15

    3D-macroporous chitosan-based scaffolds (cryogels) were produced via growth of metal-polymer coordinated complexes and electrostatic interactions between oppositely charged groups of chitosan and metal ions under subzero temperatures. A mechanism of reduction of noble metal complexes inside the cryogel walls by glutaraldehyde is proposed, which produces discrete and dispersed noble metal nanoparticles. 3D-macroporous scaffolds prepared under different conditions were characterised using TGA, FTIR, nitrogen adsorption, SEM, EDX and TEM, and the distribution of platinum nanoparticles (PtNPs) and palladium nanoparticles (PdNPs) in the material assessed. The catalytic activity of the in situ synthesised PdNPs, at 2.6, 12.5 and 21.0 μg total mass, respectively, was studied utilising a model system of 4-nitrophenol reduction. The kinetics of the reaction under different conditions (temperature, concentration of catalyst) were examined, and a decrease of catalytic activity was not observed over 17 treatment cycles. Increasing the temperature of the catalytic reaction from 10 to 22 and 35 °C by PdNPs supported within the cryogel increased the kinetic rate by 44 and 126%, respectively. Turnover number and turnover frequency of the PdNPs catalysts at room temperature were in the range 0.20-0.53 h -1 . The conversion degree of 4-nitrophenol at room temperature reached 98.9% (21.0 μg PdNPs). Significantly less mass of palladium nanoparticles (by 30-40 times) was needed compared to published data to obtain comparable rates of reduction of 4-nitrophenol. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Hierarchical Mesoporous/Macroporous Perovskite La0.5Sr0.5CoO3-x Nanotubes: A Bifunctional Catalyst with Enhanced Activity and Cycle Stability for Rechargeable Lithium Oxygen Batteries.

    PubMed

    Liu, Guoxue; Chen, Hongbin; Xia, Lu; Wang, Suqing; Ding, Liang-Xin; Li, Dongdong; Xiao, Kang; Dai, Sheng; Wang, Haihui

    2015-10-14

    Perovskites show excellent specific catalytic activity toward both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in alkaline solutions; however, small surface areas of the perovskites synthesized by traditional sol-gel methods lead to low utilization of catalytic sites, which gives rise to poor Li-O2 batteries performance and restricts their application. Herein, a hierarchical mesporous/macroporous perovskite La0.5Sr0.5CoO3-x (HPN-LSC) nanotube is developed to promote its application in Li-O2 batteries. The HPN-LSC nanotubes were synthesized via electrospinning technique followed by postannealing. The as-prepared HPN-LSC catalyst exhibits outstanding intrinsic ORR and OER catalytic activity. The HPN-LSC/KB electrode displays excellent performance toward both discharge and charge processes for Li-O2 batteries, which enhances the reversibility, the round-trip efficiency, and the capacity of resultant batteries. The synergy of high catalytic activity and hierarchical mesoporous/macroporous nanotubular structure results in the Li-O2 batteries with good rate capability and excellent cycle stability of sustaining 50 cycles at a current density of 0.1 mA cm(-2) with an upper-limit capacity of 500 mAh g(-1). The results will benefit for the future development of high-performance Li-O2 batteries using hierarchical mesoporous/macroporous nanostructured perovskite-type catalysts.

  1. Study of the structure of 3D-ordered macroporous GaN-ZnS:Mn nanocomposite films

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

    Kurdyukov, D. A., E-mail: kurd@gvg.ioffe.ru; Shishkin, I. I.; Grudinkin, S. A.

    A film-type 3D-ordered macroporous GaN-ZnS:Mn nanocomposite with the structure of an inverted opal is fabricated. Structural studies of the nanocomposite are performed, and it is shown that GaN and ZnS:Mn introduced into the pores of the silica opal are nanocrystallites misoriented with respect to each other. It is shown that the nanocomposite is a structurally perfect 3D photonic crystal. The efficiency of using a buffer of GaN crystallites to preclude interaction between the surface of the spherical a-SiO{sub 2} particles forming the opal matrix and chemically active substances introduced into the pores is demonstrated.

  2. Enrichment and separation of chlorogenic acid from the extract of Eupatorium adenophorum Spreng by macroporous resin.

    PubMed

    Liu, Boyan; Dong, Beitao; Yuan, Xiaofan; Kuang, Qirong; Zhao, Qingsheng; Yang, Mei; Liu, Jie; Zhao, Bing

    2016-01-01

    A simple and efficient chromatographic method for separation of chlorogenic acid from Eupatorium adenophorum Spreng extract was developed. The adsorption properties of nine macroporous resins were evaluated. NKA-II resin showed much better adsorption/desorption properties. The adsorption of chlorogenic acid on NKA-II resin at 25°C was well fitted to Langmuir isotherm model and pseudo-second-order kinetic model. The dynamic adsorption and desorption experiments were carried out on columns packed with NKA-II resin to optimize the separation process. The content of chlorogenic acid in the product increased to 22.17%, with a recovery yield of 82.41%. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Extraction of anthocyanins from black bean canning wastewater with macroporous resins.

    PubMed

    Wang, Xiaoxi; Hansen, Conly; Allen, Karin

    2014-02-01

    This study investigated purification of anthocyanins from black bean canning wastewater by column chromatography with 5 types of macroporous resins (Diaion Hp20, Sepabeads Sp70, Sepabeads Sp207, Sepabeads Sp700, and Sepabeads Sp710). By-product of canned black beans was partially purified by filtration, in anticipation of higher performance during column chromatography. Equilibrium adsorption isotherms were measured and analyzed using Langmuir and Freundlich isotherm models. Both Langmuir (all R² ≥ 0.98) and Freundlich (all R² ≥ 0.97) models can describe the adsorption process of anthocyanins from black bean canning wastewater using the tested resins. The adsorption and desorption behaviors of anthocyanins were studied using a dynamic method on the 5 types of resins, and Sp700 presented the highest adsorption capacity (39 ± 4 mg/g; P < 0.05) as well as desorption capacity (19 ± 2%; P < 0.05), indicating that of the resins examined, Sp700 is a better candidate for purification of anthocyanins from black bean canning wastewater. © 2014 Institute of Food Technologists®

  4. Immobilized Candida antarctica lipase B on ZnO nanowires/macroporous silica composites for catalyzing chiral resolution of (R,S)-2-octanol.

    PubMed

    Shang, Chuan-Yang; Li, Wei-Xun; Zhang, Rui-Feng

    2014-01-01

    ZnO nanowires were successfully introduced into a macroporous SiO2 by in situ hydrothermal growth in 3D pores. The obtained composites were characterized by SEM and XRD, and used as supports to immobilize Candida antarctica lipase B (CALB) through adsorption. The high specific surface area (233 m(2)/g) and strong electrostatic interaction resulted that the average loading amount of the composite supports (196.8 mg/g) was 3-4 times of that of macroporous SiO2 and approximate to that of a silica-based mesoporous material. Both adsorption capacity and the activity of the CALB immobilized on the composite supports almost kept unchanged as the samples were soaked in buffer solution for 48 h. The chiral resolution of 2-octanol was catalyzed by immobilized CALB. A maximum molar conversion of 49.1% was achieved with 99% enantiomeric excess of (R)-2-octanol acetate under the optimal condition: a reaction using 1.0 mol/L (R,S)-2-octanol, 2.0 mol/L vinyl acetate and 4.0 wt.% water content at 60°C for 8h. After fifteen recycles the immobilized lipase could retain 96.9% of relative activity and 93.8% of relative enantioselectivity. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Purification of Houttuynia cordata Thunb. Essential Oil Using Macroporous Resin Followed by Microemulsion Encapsulation to Improve Its Safety and Antiviral Activity.

    PubMed

    Pang, Jianmei; Dong, Wujun; Li, Yuhuan; Xia, Xuejun; Liu, Zhihua; Hao, Huazhen; Jiang, Lingmin; Liu, Yuling

    2017-02-15

    Essential oil extracted from Houttuynia cordata Thunb. ( H. cordata ) is widely used in traditional Chinese medicine due to its excellent biological activities. However, impurities and deficient preparations of the essential oil limit its safety and effectiveness. Herein, we proposed a strategy to prepare H. cordata essential oil (HEO) safely and effectively by combining the solvent extraction and the macroporous resin purification flexibly, and then encapsulating it using microemulsion. The extraction and purification process were optimized by orthogonal experimental design and adsorption-desorption tests, respectively. The average houttuynin content in pure HEO was then validated at 44.3% ± 2.01%, which presented a great potential for industrial application. Subsequently, pure HEO-loaded microemulsion was prepared by high-pressure homogenization and was then fully characterized. Results showed that the pure HEO-loaded microemulsion was successfully prepared with an average particle size of 179.1 nm and a high encapsulation rate of 94.7%. Furthermore, safety evaluation tests and in vitro antiviral testing indicated that the safety and activity of HEO were significantly improved after purification using D101 resin and were further improved by microemulsion encapsulation. These results demonstrated that the purification of HEO by macroporous resin followed by microemulsion encapsulation would be a promising approach for industrial application of HEO for the antiviral therapies.

  6. Feeling Abnormal: Simulation of Deviancy in Abnormal and Exceptionality Courses.

    ERIC Educational Resources Information Center

    Fernald, Charles D.

    1980-01-01

    Describes activity in which student in abnormal psychology and psychology of exceptional children classes personally experience being judged abnormal. The experience allows the students to remember relevant research, become sensitized to the feelings of individuals classified as deviant, and use caution in classifying individuals as abnormal.…

  7. Acid-base metabolism: implications for kidney stones formation.

    PubMed

    Hess, Bernhard

    2006-04-01

    The physiology and pathophysiology of renal H+ ion excretion and urinary buffer systems are reviewed. The main focus is on the two major conditions related to acid-base metabolism that cause kidney stone formation, i.e., distal renal tubular acidosis (dRTA) and abnormally low urine pH with subsequent uric acid stone formation. Both the entities can be seen on the background of disturbances of the major urinary buffer system, NH3+ <--> NH4+. On the one hand, reduced distal tubular secretion of H+ ions results in an abnormally high urinary pH and either incomplete or complete dRTA. On the other hand, reduced production/availability of NH4+ is the cause of an abnormally low urinary pH, which predisposes to uric acid stone formation. Most recent research indicates that the latter abnormality may be a renal manifestation of the increasingly prevalent metabolic syndrome. Despite opposite deviations from normal urinary pH values, both the dRTA and uric acid stone formation due to low urinary pH require the same treatment, i.e., alkali. In the dRTA, alkali is needed for improving the body's buffer capacity, whereas the goal of alkali treatment in uric acid stone formers is to increase the urinary pH to 6.2-6.8 in order to minimize uric acid crystallization.

  8. One-pot preparation of silica-supported hybrid immobilized metal affinity adsorbent with macroporous surface based on surface imprinting coating technique combined with polysaccharide incorporated sol--gel process.

    PubMed

    Li, Feng; Li, Xue-Mei; Zhang, Shu-Sheng

    2006-10-06

    A simple and reliable one-pot approach using surface imprinting coating technique combined with polysaccharide incorporated sol-gel process was established to synthesize a new organic-inorganic hybrid matrix possessing macroporous surface and functional ligand. Using mesoporous silica gel being a support, immobilized metal affinity adsorbent with a macroporous shell/mesoporous core structure was obtained after metal ion loading. In the prepared matrix, covalently bonded coating and morphology manipulation on silica gel was achieved by using one-pot sol-gel process starting from an inorganic precursor, -glycidoxypropyltrimethoxysiloxane (GPTMS), and a functional biopolymer, chitosan (CS) at the atmosphere of imprinting polyethylene glycol (PEG). Self-hydrolysis of GPTMS, self-condensation, and co-condensation of silanol groups (Si-OH) from siloxane and silica gel surface, and in situ covalent cross-linking of CS created an orderly coating on silica gel surface. PEG extraction using hot ammonium hydroxide solution gave a chemically and mechanically stabilized pore structure and deactivated residual epoxy groups. The prepared matrix was characterized by using X-ray energy dispersion spectroscopy (EDX), scanning electron microscopy (SEM) and mercury intrusion porosimetry. The matrix possessed a high capacity for copper ion loading. Protein adsorption performance of the new immobilized metal affinity adsorbent was evaluated by batch adsorption and column chromatographic experiment using bovine serum albumin (BSA) as a simple model protein. Under the optimized coating conditions, the obtained macroporous surface resulted in a fast kinetics and high capability for protein adsorption, while the matrix non-charged with metal ions offered a low non-specific adsorption.

  9. Abnormal Uterine Bleeding

    MedlinePlus

    ... abnormal uterine bleeding? Abnormal uterine bleeding is any heavy or unusual bleeding from the uterus (through your ... one symptom of abnormal uterine bleeding. Having extremely heavy bleeding during your period can also be considered ...

  10. 3D-Graphene supports for palladium nanoparticles: Effect of micro/macropores on oxygen electroreduction in Anion Exchange Membrane Fuel Cells

    NASA Astrophysics Data System (ADS)

    Kabir, Sadia; Serov, Alexey; Atanassov, Plamen

    2018-01-01

    Hierarchically structured 3D-Graphene nanosheets as supports for palladium nanoparticles (Pd/3D-GNS) were fabricated using the Sacrificial Support Method. The pore size distribution of the 3D-GNS supports were tuned by utilizing smaller and larger sized sacrificial silica templates, EH5 and L90. Using a combination of Scanning Electron Microscopy (SEM), N2 sorption and Rotating Ring Disc Electrode (RRDE) technique, it was demonstrated that the EH5 and L90 modified 3D-GNS supports had higher percentage of micro- (<2 nm) and macropores (>50 nm), respectively. The templated pores also played a role in enhancing the oxygen reduction reaction (ORR) as well as membrane electrode assembly (MEA) performance of the Pd nanoparticles in comparison to non-porous 2D-GNS supports. Particularly, incorporation of micropores increased peroxide generation at higher potentials whereas presence of macropores increased both limiting current densities and reduce peroxide yields. Integration of the Pd/GNS nanocomposites into a H2/O2 fed Anion Exchange Membrane Fuel Cell (AEMFC) operating at 60 °C also demonstrated the effect of modified porosity on concentration polarization or transport losses at high current densities. This strategy for the tunable synthesis of hierarchically 3D porous graphitized supports offers a platform for developing morphologically modified nanomaterials for energy conversion.

  11. Fate and transport of selected estrogen compounds in Hawaii soils: effect of soil type and macropores.

    PubMed

    D'Alessio, Matteo; Vasudevan, Dharni; Lichwa, Joseph; Mohanty, Sanjay K; Ray, Chittaranjan

    2014-10-01

    The fate and transport of estrogen compounds in the environment is of increasing concern due to their potential impact on freshwater organisms, ecosystems and human health. The behavior of these compounds in batch experiments suggests low mobility, while field studies indicate the persistence of estrogen compounds in the soil with the possibility of migration to surface water as well as groundwater. To better understand the movement of these chemicals through soils, we examined their transport in three different Hawaiian soils and two aqueous matrices. The three different soils used were an Oxisol, a Mollisol and a cinder, characterized by different mineralogical properties and collected at depths of 60-90 cm and 210-240 cm. Two liquid matrices were used; deionized (DI) water containing calcium chloride (CaCl2), and recycled water collected from a wastewater treatment facility. The experiments were conducted in packed and structured columns. Non-equilibrium conditions were observed during the study, especially in the structured soil. This is believed to be primarily related to the presence of macropores in the soil. The presence of macropores resulted in reduced contact time between soil and estrogens, which facilitated their transport. We found that the organic carbon content and mineralogical composition of the soils had a profound effect on the transport of the estrogens. The mobility of estrone (E1) and 17β-estradiol (E2) was greater in cinder than in the other soils. In column experiments with recycled water, earlier breakthrough peaks and longer tails of estrogens were produced compared to those observed using DI water. The use of recycled water for agricultural purposes and the siting of septic tanks and cesspools should be critically reviewed in light of these findings, especially in areas where groundwater is the primary source of potable water, such as Hawaii. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Fate and transport of selected estrogen compounds in Hawaii soils: Effect of soil type and macropores

    NASA Astrophysics Data System (ADS)

    D'Alessio, Matteo; Vasudevan, Dharni; Lichwa, Joseph; Mohanty, Sanjay K.; Ray, Chittaranjan

    2014-10-01

    The fate and transport of estrogen compounds in the environment is of increasing concern due to their potential impact on freshwater organisms, ecosystems and human health. The behavior of these compounds in batch experiments suggests low mobility, while field studies indicate the persistence of estrogen compounds in the soil with the possibility of migration to surface water as well as groundwater. To better understand the movement of these chemicals through soils, we examined their transport in three different Hawaiian soils and two aqueous matrices. The three different soils used were an Oxisol, a Mollisol and a cinder, characterized by different mineralogical properties and collected at depths of 60-90 cm and 210-240 cm. Two liquid matrices were used; deionized (DI) water containing calcium chloride (CaCl2), and recycled water collected from a wastewater treatment facility. The experiments were conducted in packed and structured columns. Non-equilibrium conditions were observed during the study, especially in the structured soil. This is believed to be primarily related to the presence of macropores in the soil. The presence of macropores resulted in reduced contact time between soil and estrogens, which facilitated their transport. We found that the organic carbon content and mineralogical composition of the soils had a profound effect on the transport of the estrogens. The mobility of estrone (E1) and 17β-estradiol (E2) was greater in cinder than in the other soils. In column experiments with recycled water, earlier breakthrough peaks and longer tails of estrogens were produced compared to those observed using DI water. The use of recycled water for agricultural purposes and the siting of septic tanks and cesspools should be critically reviewed in light of these findings, especially in areas where groundwater is the primary source of potable water, such as Hawaii.

  13. Ordered nanoporous silica as carriers for improved delivery of water insoluble drugs: a comparative study between three dimensional and two dimensional macroporous silica

    PubMed Central

    Wang, Ying; Zhao, Qinfu; Hu, Yanchen; Sun, Lizhang; Bai, Ling; Jiang, Tongying; Wang, Siling

    2013-01-01

    The goal of the present study was to compare the drug release properties and stability of the nanoporous silica with different pore architectures as a matrix for improved delivery of poorly soluble drugs. For this purpose, three dimensional ordered macroporous (3DOM) silica with 3D continuous and interconnected macropores of different sizes (200 nm and 500 nm) and classic mesoporous silica (ie, Mobil Composition of Matter [MCM]-41 and Santa Barbara Amorphous [SBA]-15) with well-ordered two dimensional (2D) cylindrical mesopores were successfully fabricated and then loaded with the model drug indomethacin (IMC) via the solvent deposition method. Scanning electron microscopy (SEM), N2 adsorption, differential scanning calorimetry (DSC), and X-ray diffraction (XRD) were applied to systematically characterize all IMC-loaded nanoporous silica formulations, evidencing the successful inclusion of IMC into nanopores, the reduced crystallinity, and finally accelerated dissolution of IMC. It was worth mentioning that, in comparison to 2D mesoporous silica, 3DOM silica displayed a more rapid release profile, which may be ascribed to the 3D interconnected pore networks and the highly accessible surface areas. The results obtained from the stability test indicated that the amorphous state of IMC entrapped in the 2D mesoporous silica (SBA-15 and MCM-41) has a better physical stability than in that of 3DOM silica. Moreover, the dissolution rate and stability of IMC loaded in 3DOM silica was closely related to the pore size of macroporous silica. The colorimetric 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Cell Counting Kit (CCK)-8 assays in combination with direct morphology observations demonstrated the good biocompatibility of nanoporous silica, especially for 3DOM silica and SBA-15. The present work encourages further study of the drug release properties and stability of drug entrapped in different pore architecture of silica in order to realize

  14. Toward Scalable Fabrication of Hierarchical Silica Capsules with Integrated Micro-, Meso-, and Macropores.

    PubMed

    Zhou, Weizheng; Tong, Gangsheng; Wang, Dali; Zhu, Bangshang; Ren, Yu; Butler, Michael; Pelan, Eddie; Yan, Deyue; Zhu, Xinyuan; Stoyanov, Simeon D

    2016-04-06

    Hierarchical porous structures are ubiquitous in biological organisms and inorganic systems. Although such structures have been replicated, designed, and fabricated, they are often inferior to naturally occurring analogues. Apart from the complexity and multiple functionalities developed by the biological systems, the controllable and scalable production of hierarchically porous structures and building blocks remains a technological challenge. Herein, a facile and scalable approach is developed to fabricate hierarchical hollow spheres with integrated micro-, meso-, and macropores ranging from 1 nm to 100 μm (spanning five orders of magnitude). (Macro)molecules, micro-rods (which play a key role for the creation of robust capsules), and emulsion droplets have been successfully employed as multiple length scale templates, allowing the creation of hierarchical porous macrospheres. Thanks to their specific mechanical strength, these hierarchical porous spheres could be incorporated and assembled as higher level building blocks in various novel materials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. A novel electrochemical sensor based on zirconia/ordered macroporous polyaniline for ultrasensitive detection of pesticides.

    PubMed

    Wang, Yonglan; Jin, Jun; Yuan, Caixia; Zhang, Fan; Ma, Linlin; Qin, Dongdong; Shan, Duoliang; Lu, Xiaoquan

    2015-01-21

    A simple and mild strategy was proposed to develop a novel electrochemical sensor based on zirconia/ordered macroporous polyaniline (ZrO2/OMP) and further used for the detection of methyl parathion (MP), one of the organophosphate pesticides (OPPs). Due to the strong affinity of phosphate groups with ZrO2 and the advantages of OMP such as high catalytic activity and good conductivity, the developed sensor showed a limit of detection as low as 2.28 × 10(-10) mol L(-1) (S/N = 3) by square-wave voltammograms, and good selectivity, acceptable reproducibility and stability. Most importantly, this novel sensor was successfully applied to detect MP in real samples of apple and cabbage. It is expected that this method has potential applications in electrochemical sensing platforms with simple, sensitive, selective and fast analysis.

  16. Preparation and evaluation of a macroporous molecularly imprinted hybrid silica monolithic column for recognition of proteins by high performance liquid chromatography.

    PubMed

    Lin, Zian; Yang, Fan; He, Xiwen; Zhao, Xiaomiao; Zhang, Yukui

    2009-12-04

    A novel type of macroporous molecularly imprinted hybrid silica monolithic column was first developed for recognition of proteins. The macroporous silica-based monolithic skeleton was synthesized in a 4.6mm i.d. stainless steel column by a mild sol-gel process with methyltrimethoxysilane (MTMS) as a sole precursor, and then vinyl groups were introduced onto the surface of the silica skeleton by chemical modification of gamma-methacryloxypropyltrimethoxysilane (gamma-MAPS). Subsequently, the molecularly imprinted polymer (MIP) coating was copolymerized and anchored onto the surface of the silica monolith. Bovine serum albumin (BSA) and lysozyme (Lyz), which differ greatly in molecular size, isoelectric point, and charge, were representatively selected for imprinted templates to evaluate recognition property of the hybrid silica-based MIP monolith. Some important factors, such as template-monomer molar ratio, total monomer concentration and crosslinking density, were systematically investigated. Under the optimum conditions, the obtained hybrid silica-based MIP monolith showed higher binding affinity for template than its corresponding non-imprinted (NIP) monolith. The imprinted factor (IF) for BSA and Lyz reached 9.07 and 6.52, respectively. Moreover, the hybrid silica-based MIP monolith displayed favorable binding characteristics for template over competitive protein. Compared with the imprinted silica beads for stationary phase and in situ organic polymer-based hydrogel MIP monolith, the hybrid silica MIP monolith exhibited higher recognition, stability and lifetime.

  17. Induced Abnormality In Mir- and Earth-Grown Super Dwarf Wheat

    NASA Technical Reports Server (NTRS)

    Bubenheim, David L.; Stieber, Joseph; Campbell, William F.; Salisbury, Frank B.; Levinski, Margarita; Sytchev, Vladimir; Podolsky, Igor; Chernova, Lola; Ivanova, Irene; Kliss, Mark (Technical Monitor)

    1998-01-01

    Super-dwarf wheat grown on the Mir space station using the Svet "Greenhouse" exhibited morphological, metabolic and reproductive abnormalities compared with normal wheat. Of prominent importance were the abnormalities associated with reproductive ontogeny and the total absence of seed formation on Mir. Changes in the apical meristem associated with transition from the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super Dwarf' wheat up to the point of anthesis. Observation of ruptured anthers from the Mir-grown plants revealed what appeared to be normally developed pollen. These pollen grains however, contain only one nucleus, while normal viable pollen is trinucleate. A potentially important difference in the flight experiment, compared with ground reference studies, was identified - a high level of atmospheric ethylene (1200 ppb). Ground studies conducted exposing "Super-dwarf" wheat to ethylene at just prior to anthesis resulted in manifestation of the same abnormalities observed in the space flight samples.

  18. Meiotic abnormalities

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

    NONE

    1993-12-31

    Chapter 19, describes meiotic abnormalities. These include nondisjunction of autosomes and sex chromosomes, genetic and environmental causes of nondisjunction, misdivision of the centromere, chromosomally abnormal human sperm, male infertility, parental age, and origin of diploid gametes. 57 refs., 2 figs., 1 tab.

  19. Hydronephrosis in the Wnt5a-ablated kidney is caused by an abnormal ureter-bladder connection.

    PubMed

    Yun, Kangsun; Perantoni, Alan O

    The Wnt5a null mouse is a complex developmental model which, among its several posterior-localized axis defects, exhibits multiple kidney phenotypes, including duplex kidney and loss of the medullary zone. We previously reported that ablation of Wnt5a in nascent mesoderm causes duplex kidney formation as a result of aberrant development of the nephric duct and abnormal extension of intermediate mesoderm. However, these mice also display a loss of the medullary region late in gestation. We have now genetically isolated duplex kidney formation from the medullary defect by specifically targeting the progenitors for both the ureteric bud and metanephric mesenchyme. The conditional mutants fail to form a normal renal medulla but no longer exhibit duplex kidney formation. Approximately 1/3 of the mutants develop hydronephrosis in the kidneys either uni- or bilaterally when using Dll1Cre. The abnormal kidney phenotype becomes prominent at E16.5, which approximates the time when urine production begins in the mouse embryonic kidney, and is associated with a dramatic increase in apoptosis only in mutant kidneys with hydronephrosis. Methylene blue dye injection and histologic examination reveal that aberrant cell death likely results from urine toxicity due to an abnormal ureter-bladder connection. This study shows that Wnt5a is not required for development of the renal medulla and that loss of the renal medullary region in the Wnt5a-deleted kidney is caused by an abnormal ureter-bladder connection. Published by Elsevier B.V.

  20. Mesopore- and Macropore-Dominant Nitrogen-Doped Hierarchically Porous Carbons for High-Energy and Ultrafast Supercapacitors in Non-Aqueous Electrolytes.

    PubMed

    Shao, Rong; Niu, Jin; Liang, Jingjing; Liu, Mengyue; Zhang, Zhengping; Dou, Meiling; Huang, Yaqin; Wang, Feng

    2017-12-13

    Non-aqueous electrolytes (e.g., organic and ionic liquid electrolytes) can undergo high working voltage to improve the energy densities of supercapacitors. However, the large ion sizes, high viscosities, and low ionic conductivities of organic and ionic liquid electrolytes tend to cause the low specific capacitances, poor rate, and cycling performance of supercapacitors based on conventional micropore-dominant activated carbon electrodes, limiting their practical applications. Herein, we propose an effective strategy to simultaneously obtain high power and energy densities in non-aqueous electrolytes via using a cattle bone-derived porous carbon as an electrode material. Because of the unique co-activation of KOH and hydroxyapatite (HA) within the cattle bone, nitrogen-doped hierarchically porous carbon (referred to as NHPC-HA/KOH) is obtained and possesses a mesopore- and macropore-dominant porosity with an ultrahigh specific surface area (2203 m 2 g -1 ) of meso- and macropores. The NHPC-HA/KOH electrodes exhibit superior performance with specific capacitances of 224 and 240 F g -1 at 5 A g -1 in 1.0 M TEABF 4 /AN and neat EMIMBF 4 electrolyte, respectively. The symmetric supercapacitor using NHPC-HA/KOH electrodes can deliver integrated high energy and power properties (48.6 W h kg -1 at 3.13 kW kg -1 in 1.0 M TEABF 4 /AN and 75 W h kg -1 at 3.75 kW kg -1 in neat EMIMBF 4 ), as well as superior cycling performance (over 89% of the initial capacitance after 10 000 cycles at 10 A g -1 ).

  1. Matrix Elasticity of Void-Forming Hydrogels Controls Transplanted Stem Cell-Mediated Bone Formation

    PubMed Central

    Huebsch, Nathaniel; Lippens, Evi; Lee, Kangwon; Mehta, Manav; Koshy, Sandeep T; Darnell, Max C; Desai, Rajiv; Madl, Christopher M.; Xu, Maria; Zhao, Xuanhe; Chaudhuri, Ovijit; Verbeke, Catia; Kim, Woo Seob; Alim, Karen; Mammoto, Akiko; Ingber, Donald E.; Duda, Georg N; Mooney, David J.

    2015-01-01

    The effectiveness of stem-cell therapies has been hampered by cell death and limited control over fate1. These problems can be partially circumvented by using macroporous biomaterials that improve the survival of transplanted stem cells and provide molecular cues to direct cell phenotype2–4. Stem cell behavior can also be controlled in vitro by manipulating the elasticity of both porous and non-porous materials5–7, yet translation to therapeutic processes in vivo remains elusive. Here, by developing injectable, void-forming hydrogels that decouple pore formation from elasticity, we show that mesenchymal stem cell (MSC) osteogenesis in vitro, and cell deployment in vitro and in vivo, can be controlled by modifying, respectively, the hydrogel's elastic modulus or its chemistry. When the hydrogels were used to transplant MSCs, the hydrogel's elasticity regulated bone regeneration, with optimal bone formation at 60 kPa. Our findings show that biophysical cues can be harnessed to direct therapeutic stem-cell behaviors in situ. PMID:26366848

  2. Matrix elasticity of void-forming hydrogels controls transplanted-stem-cell-mediated bone formation

    NASA Astrophysics Data System (ADS)

    Huebsch, Nathaniel; Lippens, Evi; Lee, Kangwon; Mehta, Manav; Koshy, Sandeep T.; Darnell, Max C.; Desai, Rajiv M.; Madl, Christopher M.; Xu, Maria; Zhao, Xuanhe; Chaudhuri, Ovijit; Verbeke, Catia; Kim, Woo Seob; Alim, Karen; Mammoto, Akiko; Ingber, Donald E.; Duda, Georg N.; Mooney, David J.

    2015-12-01

    The effectiveness of stem cell therapies has been hampered by cell death and limited control over fate. These problems can be partially circumvented by using macroporous biomaterials that improve the survival of transplanted stem cells and provide molecular cues to direct cell phenotype. Stem cell behaviour can also be controlled in vitro by manipulating the elasticity of both porous and non-porous materials, yet translation to therapeutic processes in vivo remains elusive. Here, by developing injectable, void-forming hydrogels that decouple pore formation from elasticity, we show that mesenchymal stem cell (MSC) osteogenesis in vitro, and cell deployment in vitro and in vivo, can be controlled by modifying, respectively, the hydrogel’s elastic modulus or its chemistry. When the hydrogels were used to transplant MSCs, the hydrogel’s elasticity regulated bone regeneration, with optimal bone formation at 60 kPa. Our findings show that biophysical cues can be harnessed to direct therapeutic stem cell behaviours in situ.

  3. Efficient extraction and preparative separation of four main isoflavonoids from Dalbergia odorifera T. Chen leaves by deep eutectic solvents-based negative pressure cavitation extraction followed by macroporous resin column chromatography.

    PubMed

    Li, Lu; Liu, Ju-Zhao; Luo, Meng; Wang, Wei; Huang, Yu-Yan; Efferth, Thomas; Wang, Hui-Mei; Fu, Yu-Jie

    2016-10-15

    In this study, green and efficient deep eutectic solvent-based negative pressure cavitation-assisted extraction (DES-NPCE) followed by macroporous resin column chromatography was developed to extract and separate four main isoflavonoids, i.e. prunetin, tectorigenin, genistein and biochanin A from Dalbergia odorifera T. Chen leaves. The extraction procedure was optimized systematically by single-factor experiments and a Box-Behnken experimental design combined with response surface methodology. The maximum extraction yields of prunetin, tectorigenin, genistein and biochanin A reached 1.204, 1.057, 0.911 and 2.448mg/g dry weight, respectively. Moreover, the direct enrichment and separation of four isoflavonoids in DES extraction solution was successfully achieved by macroporous resin AB-8 with recovery yields of more than 80%. The present study provides a convenient and efficient method for the green extraction and preparative separation of active compounds from plants. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Developmental abnormalities in Glomeris marginata (Villers 1789) (Myriapoda: Diplopoda): implications for body axis determination in a myriapod

    NASA Astrophysics Data System (ADS)

    Janssen, Ralf

    2013-01-01

    Abnormally developing embryos (ADEs) of the common pill millipede Glomeris marginata have been investigated by means of nuclear staining and mRNA in situ hybridization. It showed that all ADEs represent cases of Duplicitas posterior, which means that the posterior body pole is duplicated. The severity of the duplication ranges from duplicated posterior trunk segments in one specimen to an almost completely duplicated specimen that only shares the very anterior head region. Remarkably, none of the encountered ADEs represents a case of Duplicitas anterior (duplicated anterior pole) or a case of Duplicitas cruciata (cruciate duplication with two anterior and two posterior poles). This observation is discussed in the light of earlier reports on G. marginata ADEs that claim to have found these abnormalities. The lack of any other axial abnormality aside from D. posterior implies that early axis determination in G. marginata, and possibly myriapods in general, underlies the developmental mechanisms that prevent the formation of any other type of axial duplication. It is proposed that the formation of D. posterior-type embryos could be caused by the formation of two instead of only one posterior cumulus early during development.

  5. Inexpensive method for producing macroporous silicon particulates (MPSPs) with pyrolyzed polyacrylonitrile for lithium ion batteries

    PubMed Central

    Thakur, Madhuri; Sinsabaugh, Steven L.; Isaacson, Mark J.; Wong, Michael S.; Biswal, Sibani Lisa

    2012-01-01

    One of the most exciting areas in lithium ion batteries is engineering structured silicon anodes. These new materials promise to lead the next generation of batteries with significantly higher reversible charge capacity than current technologies. One drawback of these materials is that their production involves costly processing steps, limiting their application in commercial lithium ion batteries. In this report we present an inexpensive method for synthesizing macroporous silicon particulates (MPSPs). After being mixed with polyacrylonitrile (PAN) and pyrolyzed, MPSPs can alloy with lithium, resulting in capacities of 1000 mAhg−1 for over 600+ cycles. These sponge-like MPSPs with pyrolyzed PAN (PPAN) can accommodate the large volume expansion associated with silicon lithiation. This performance combined with low cost processing yields a competitive anode material that will have an immediate and direct application in lithium ion batteries. PMID:23139860

  6. Abnormal Uterine Bleeding FAQ

    MedlinePlus

    ... Abnormal Uterine Bleeding • What is a normal menstrual cycle? • When is bleeding abnormal? • At what ages is ... abnormal bleeding? •Glossary What is a normal menstrual cycle? The normal length of the menstrual cycle is ...

  7. Three-dimensionally Ordered Macroporous Structure Enabled Nanothermite Membrane of Mn2O3/Al

    PubMed Central

    Zheng, Guoqiang; Zhang, Wenchao; Shen, Ruiqi; Ye, Jiahai; Qin, Zhichun; Chao, Yimin

    2016-01-01

    Mn2O3 has been selected to realize nanothermite membrane for the first time in the literature. Mn2O3/Al nanothermite has been synthesized by magnetron sputtering a layer of Al film onto three-dimensionally ordered macroporous (3DOM) Mn2O3 skeleton. The energy release is significantly enhanced owing to the unusual 3DOM structure, which ensures Al and Mn2O3 to integrate compactly in nanoscale and greatly increase effective contact area. The morphology and DSC curve of the nanothermite membrane have been investigated at various aluminizing times. At the optimized aluminizing time of 30 min, energy release reaches a maximum of 2.09 kJ∙g−1, where the Al layer thickness plays a decisive role in the total energy release. This method possesses advantages of high compatibility with MEMS and can be applied to other nanothermite systems easily, which will make great contribution to little-known nanothermite research. PMID:26935405

  8. Visual and reversible carbon dioxide sensing enabled by doctor blade coated macroporous photonic crystals.

    PubMed

    Lin, Yi-Han; Suen, Shing-Yi; Yang, Hongta

    2017-11-15

    With significant impacts of carbon dioxide on global climate change, carbon dioxide sensing is of great importance. However, most of the existing sensing technologies are prone to interferences from carbon monoxide, or suffer from the use of sophisticated instruments. This research reports the development of reproducible carbon dioxide sensor using roll-to-roll compatible doctor blade coated three-dimensional macroporous photonic crystals. The pores are functionalized with amine groups to allow the reaction with carbon dioxide in the presence of humidity. The adsorption of carbon dioxide leads to red-shift and amplitude reduction of the optical stop bands, resulting in carbon dioxide detection with visible readout. The dependences of the diffraction wavelength on carbon dioxide partial pressure for various amine-functionalized photonic crystals and different humidities in the environment are systematically investigated. In addition, the reproducibility of carbon dioxide sensing has also been demonstrated in this research. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Induced abnormality in Mir- and Earth grown Super Dwarf wheat.

    PubMed

    Bubenheim, D L; Stieber, J; Campbell, W F; Salisbury, F B; Levinski, M; Sytchev, V; Podolsky, I; Chernova, L; Pdolsky, I

    2003-01-01

    Super-dwarf wheat grown on the Mir space station using the Svet "Greenhouse" exhibited morphological, metabolic and reproductive abnormalities compared with Earth-grown wheat. Of prominent importance were the abnormalities associated with reproductive ontogeny and the total absence of seed formation on Mir. Changes in the apical meristem associated with transition from the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super-Dwarf' wheat up to the point of anthesis. Observation of ruptured anthers from the Mir-grown plants revealed what appeared to be normally developed pollen. These pollen gains, however, contained only one nuclei, while normal viable pollen is tri-nucleate. A potentially important difference in the flight experiment, compared with ground reference studies, was the presence of a high level of atmospheric ethylene (1,200 ppb). Ground studies conducted by exposing 'Super-Dwarf' wheat to ethylene just prior to anthesis resulted in manifestation of the same abnormalities observed in the space flight samples. c2002 Published by Elsevier Science Ltd on behalf of COSPAR.

  10. Induced abnormality in Mir- and Earth grown Super Dwarf wheat

    NASA Technical Reports Server (NTRS)

    Bubenheim, D. L.; Stieber, J.; Campbell, W. F.; Salisbury, F. B.; Levinski, M.; Sytchev, V.; Podolsky, I.; Chernova, L.; Pdolsky, I.

    2003-01-01

    Super-dwarf wheat grown on the Mir space station using the Svet "Greenhouse" exhibited morphological, metabolic and reproductive abnormalities compared with Earth-grown wheat. Of prominent importance were the abnormalities associated with reproductive ontogeny and the total absence of seed formation on Mir. Changes in the apical meristem associated with transition from the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super-Dwarf' wheat up to the point of anthesis. Observation of ruptured anthers from the Mir-grown plants revealed what appeared to be normally developed pollen. These pollen gains, however, contained only one nuclei, while normal viable pollen is tri-nucleate. A potentially important difference in the flight experiment, compared with ground reference studies, was the presence of a high level of atmospheric ethylene (1,200 ppb). Ground studies conducted by exposing 'Super-Dwarf' wheat to ethylene just prior to anthesis resulted in manifestation of the same abnormalities observed in the space flight samples. c2002 Published by Elsevier Science Ltd on behalf of COSPAR.

  11. Synthesis of three-dimensionally ordered macroporous manganese dioxide-carbon nanocomposites for supercapacitors

    NASA Astrophysics Data System (ADS)

    Liu, Zhi; Tan, Xiuli; Gao, Xin; Song, Lihong

    2014-12-01

    In this article, we report a composite of MnO2 nanoparticles supported by three-dimensionally ordered macroporous carbon (MnO2/3DOM carbon nanocomposites) fabricated by means of a simple multi-component infiltration of three-dimensional templates. MnO2 nanoparticles of 2 nm-6 nm are observed to be highly dispersed on the 3DOM carbon scaffolds. Cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy techniques are employed to assess the properties of these nanocomposites for use in supercapacitors. The results demonstrate that MnO2 can be effectively utilized with assistance of the 3DOM carbon in the electrode. The specific capacitance of the nanocomposite electrode can reach as high as 347 F g-1 at a current density of 0.5 A g-1. Moreover, the electrode exhibit excellent charge/discharge rate and good cycling stability, retaining over 92% of its initial charge after 5500 cycles at a current density of 2.5 A g-1. Such MnO2/3DOM carbon nanocomposite represents a promising exploring direction for enhancing the device performance of metal oxide-based electrochemical supercapacitors.

  12. Enhanced geometries of macroporous silicon photonic crystals for optical gas sensing applications

    NASA Astrophysics Data System (ADS)

    Cardador, D.; Vega, D.; Segura, D.; Trifonov, T.; Rodríguez, A.

    2017-07-01

    A macroporous silicon photonic crystal is designed and optimized theoretically for its use in gas sensing applications and IR optical filters. Light impinges perpendicularly onto the sample surface (vertical propagation) so a three-dimensional (3d) structure is used. For gas sensing, a sharp resonance is desired in order to isolate an absorption line of the gas of interest. The high Q-factors needed mandate the use of a plane defect inside the PhC to give rise to a resonant mode inside the bandgap tuned to the gas absorption line. Furthermore to allow gas passage through the device, an open membrane is required. This can affect the mechanical resilience. To improve the strength of the photonic crystal the pores are extended after the ;active; 3d part. The number of modulations, and the extension length have been optimized to obtain the largest Q-factor with reasonable transmitted power. These proposed structures have been experimentally performed, probing an enhancement of almost an order of magnitude in the Q-factor in respect with the basic case. Simulations considering CO2 have been performed showing that the proposed structures are promising as precise optical gas sensors.

  13. Bone-like apatite growth on controllable macroporous titanium scaffolds coated with microporous titania.

    PubMed

    Rao, Xi; Li, Jing; Feng, Xue; Chu, Chenglin

    2018-01-01

    In this study, a simple, cost-effective approach of polymeric foam replication was used to produce three-dimensionally macroporous titanium scaffolds with controllable porosities and mechanical properties. Two kinds of porous titanium scaffolds with different porosities (74.7% and 87.6%) and pore sizes (360µm and 750µm) were fabricated. Both of the scaffolds exhibit good compressive strength (24.5MPa and 13.5MPa) with a low elastic modulus (0.23GPa and 0.11GPa), approximating the mechanical properties of nature human cancellous bone (E = 10-50MPa, σ = 0.01-3.0GPa). Thereafter, the scaffolds were surface modified using plasma electrolyte oxidation (PEO) process to gain a bioactive porous titania ceramic coating. The SBF immersion test indicates PEO treated scaffolds show excellent bioactivity as the apatite rapidly nucleates and grows on the scaffold surface during 3-28 days. The results suggest that the highly porous titanium scaffolds with titania bioactive coatings are promising in cancellous bone replacement. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Template-assisted electrostatic spray deposition as a new route to mesoporous, macroporous, and hierarchically porous oxide films.

    PubMed

    Sokolov, S; Paul, B; Ortel, E; Fischer, A; Kraehnert, R

    2011-03-01

    A novel film coating technique, template-assisted electrostatic spray deposition (TAESD), was developed for the synthesis of porous metal oxide films and tested on TiO(2). Organic templates are codeposited with the titania precursor by electrostatic spray deposition and then removed during calcination. Resultant films are highly porous with pores casted by uniformly sized templates, which introduced a new level of control over the pore morphology for the ESD method. Employing the amphiphilic block copolymer Pluronic P123, PMMA latex spheres, or a combination of the two, mesoporous, macroporous, and hierarchically porous TiO(2) films are obtained. Decoupled from other coating parameters, film thickness can be controlled by deposition time or depositing multiple layers while maintaining the coating's structure and integrity.

  15. Urine - abnormal color

    MedlinePlus

    ... medlineplus.gov/ency/article/003139.htm Urine - abnormal color To use the sharing features on this page, please enable JavaScript. The usual color of urine is straw-yellow. Abnormally colored urine ...

  16. Batch and fixed-bed column study for p-nitrophenol, methylene blue, and U(VI) removal by polyvinyl alcohol-graphene oxide macroporous hydrogel bead.

    PubMed

    Chen, Dan; Zhou, Jun; Wang, Hongyu; Yang, Kai

    2018-01-01

    There is an increasing need to explore effective and clean approaches for hazardous contamination removal from wastewaters. In this work, a novel bead adsorbent, polyvinyl alcohol-graphene oxide (PVA-GO) macroporous hydrogel bead was prepared as filter media for p-nitrophenol (PNP), dye methylene blue (MB), and heavy metal U(VI) removal from aqueous solution. Batch and fixed-bed column experiments were carried out to evaluate the adsorption capacities of PNP, MB, and U(VI) on this bead. From batch experiments, the maximum adsorption capacities of PNP, MB, and U(VI) reached 347.87, 422.90, and 327.55 mg/g. From the fixed-bed column experiments, the adsorption capacities of PNP, MB, and U(VI) decreased with initial concentration increasing from 100 to 400 mg/L. The adsorption capacities of PNP, MB, and U(VI) decreased with increasing flow rate. Also, the maximum adsorption capacity of PNP decreased as pH increased from 3 to 9, while MB and U(VI) presented opposite tendencies. Furthermore, the bed depth service Time (BDST) model showed good linear relationships for the three ions' adsorption processes in this fixed-bed column, which indicated that the BDST model effectively evaluated and optimized the adsorption process of PVA-GO macroporous hydrogel bead in fixed-bed columns for hazardous contaminant removal from wastewaters.

  17. Thrombin impairs human endometrial endothelial angiogenesis; implications for progestin-only contraceptive-induced abnormal uterine bleeding.

    PubMed

    Shapiro, John P; Guzeloglu-Kayisli, Ozlem; Kayisli, Umit A; Semerci, Nihan; Huang, S Joseph; Arlier, Sefa; Larsen, Kellie; Fadda, Paolo; Schatz, Frederick; Lockwood, Charles J

    2017-06-01

    Progestin-only contraceptives induce abnormal uterine bleeding, accompanied by prothrombin leakage from dilated endometrial microvessels and increased thrombin generation by human endometrial stromal cell (HESC)-expressed tissue factor. Initial studies of the thrombin-treated HESC secretome identified elevated levels of cleaved chondroitin sulfate proteoglycan 4 (CSPG4), impairing pericyte-endothelial interactions. Thus, we investigated direct and CSPG4-mediated effects of thrombin in eliciting abnormal uterine bleeding by disrupting endometrial angiogenesis. Liquid chromatography/tandem mass spectrometry, enzyme-linked immunosorbent assay (ELISA) and quantitative real-time-polymerase chain reaction (PCR) evaluated conditioned medium supernatant and cell lysates from control versus thrombin-treated HESCs. Pre- and post-Depo medroxyprogesterone acetate (DMPA)-administered endometria were immunostained for CSPG4. Proliferation, apoptosis and tube formation were assessed in human endometrial endothelial cells (HEECs) incubated with recombinant human (rh)-CSPG4 or thrombin or both. Thrombin induced CSPG4 protein expression in cultured HESCs as detected by mass spectrometry and ELISA (p<.02, n=3). Compared to pre-DMPA endometria (n=5), stromal cells in post-DMPA endometria (n=5) displayed stronger CSPG4 immunostaining. In HEEC cultures (n=3), total tube-formed mesh area was significantly higher in rh-CSPG4 versus control (p<.05). However, thrombin disrupted HEEC tube formation by a concentration- and time-dependent reduction of angiogenic parameters (p<.05), whereas CSPG4 co-treatment did not reverse these thrombin-mediated effects. These results suggest that disruption of HEEC tube formation by thrombin induces aberrant angiogenesis and abnormal uterine bleeding in DMPA users. Mass spectrometry analysis identified several HESC-secreted proteins regulated by thrombin. Therapeutic agents blocking angiogenic effects of thrombin in HESCs can prevent or minimize progestin

  18. Abnormal pressures as hydrodynamic phenomena

    USGS Publications Warehouse

    Neuzil, C.E.

    1995-01-01

    So-called abnormal pressures, subsurface fluid pressures significantly higher or lower than hydrostatic, have excited speculation about their origin since subsurface exploration first encountered them. Two distinct conceptual models for abnormal pressures have gained currency among earth scientists. The static model sees abnormal pressures generally as relict features preserved by a virtual absence of fluid flow over geologic time. The hydrodynamic model instead envisions abnormal pressures as phenomena in which flow usually plays an important role. This paper develops the theoretical framework for abnormal pressures as hydrodynamic phenomena, shows that it explains the manifold occurrences of abnormal pressures, and examines the implications of this approach. -from Author

  19. Biotemplated syntheses of macroporous materials for bone tissue engineering scaffolds and experiments in vitro and vivo.

    PubMed

    Li, Xing; Zhao, Yayun; Bing, Yue; Li, Yaping; Gan, Ning; Guo, Zhiyong; Peng, Zhaoxiang; Zhu, Yabin

    2013-06-26

    The macroporous materials were prepared from the transformation of cuttlebone as biotemplates under hydrothermal reactions and characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric/differential thermal analyses (TG-DTA), and scanning electron microscopy (SEM). Cell experimental results showed that the prepared materials as bone tissue engineering scaffolds or fillers had fine biocompatibility suitable for adhesion and proliferation of the hMSCs (human marrow mesenchymal stem cells). Histological analyses were carried out by implanting the scaffolds into a rabbit femur, where the bioresorption, degradation, and biological activity of the scaffolds were observed in the animal body. The prepared scaffolds kept the original three-dimensional frameworks with the ordered porous structures, which made for blood circulation, nutrition supply, and the cells implantation. The biotemplated syntheses could provide a new effective approach to prepare the bone tissue engineering scaffold materials.

  20. Abnormal development of floral meristem triggers defective morphogenesis of generative system in transgenic tomatoes.

    PubMed

    Chaban, Inna; Khaliluev, Marat; Baranova, Ekaterina; Kononenko, Neonila; Dolgov, Sergey; Smirnova, Elena

    2018-04-21

    Parthenocarpy and fruit malformations are common among independent transgenic tomato lines, expressing genes encoding different pathogenesis-related (PR) protein and antimicrobal peptides. Abnormal phenotype developed independently of the expression and type of target genes, but distinctive features during flower and fruit development were detected in each transgenic line. We analyzed the morphology, anatomy, and cytoembryology of abnormal flowers and fruits from these transgenic tomato lines and compared them with flowers and fruits of wild tomatoes, line YaLF used for transformation, and transgenic plants with normal phenotype. We confirmed that the main cause of abnormal flower and fruit development was the alterations of determinate growth of generative meristem. These alterations triggered different types of anomalous growth, affecting the number of growing ectopic shoots and formation of new flowers. Investigation of the ovule ontogenesis did not show anomalies in embryo sac development, but fertilization did not occur and embryo sac degenerated. Nevertheless, the ovule continued to differentiate due to proliferation of endothelium cells. The latter substituted embryo sac and formed pseudoembryonic tissue. This process imitated embryogenesis and stimulated ovary growth, leading to the development of parthenocarpic fruit. We demonstrated that failed fertilization occurred due to defective male gametophyte formation, which was manifested in blocked division of the nucleus in the microspore and arrest of vegetative and generative cell formation. Maturing pollen grains were overgrown microspores, not competent for fertilization but capable to induce proliferation of endothelium and development of parthenocarpic ovary. Thus, our study provided new data on the structural transformations of reproductive organs during development of parthenocarpic fruits in transgenic tomato.

  1. Liquid-liquid two phase systems for the production of porous hydrogels and hydrogel microspheres for biomedical applications: A tutorial review

    PubMed Central

    Elbert, Donald L.

    2010-01-01

    Macroporous hydrogels may have direct applications in regenerative medicine as scaffolds to support tissue formation. Hydrogel microspheres may be used as drug delivery vehicles or as building blocks to assemble modular scaffolds. A variety of techniques exist to produce macroporous hydrogels and hydrogel microspheres. A subset of these relies on liquid-liquid two phase systems. Within this subset, vastly different types of polymerization processes are found. In this review, the history, terminology and classification of liquid-liquid two phase polymerization and crosslinking are described. Instructive examples of hydrogel microsphere and macroporous scaffold formation by precipitation/dispersion, emulsion and suspension polymerizations are used to illustrate the nature of these processes. The role of the kinetics of phase separation in determining the morphology of scaffolds and microspheres is also delineated. Brief descriptions of miniemulsion, microemulsion polymerization and ionotropic gelation are also included. PMID:20659596

  2. Development of a process for separation of mogroside V from Siraitia grosvenorii by macroporous resins.

    PubMed

    Zhang, Min; Yang, Huihua; Zhang, Hongyang; Wang, Yuerong; Hu, Ping

    2011-08-25

    A separation method was developed for the preparative separation and enrichment of the non-caloric sweetener mogroside V from Siraitia grosvenorii. The adsorption properties of six macroporous resins were evaluated. Results showed that HZ 806 resin offered the best adsorption and desorption capacities. Based on the adsorption experiments on HZ 806, the adsorption data were found to fit the Freundlich model well. The pseudo-second-order kinetic model showed the highest correlation with the experimental results. Separation was performed with deionized water and 40% aqueous ethanol solution as mobile phases. In a typical run, 100 g of herb was processed and 3.38 g of mogroside V with a purity of 10.7% was harvested. This separation method provided a 15.1-fold increase in the purification factor from 0.5% to 10.7%. The present study showed that HZ 806 resins were effective for the separation and enrichment of mogroside V from S. grosvenorii.

  3. Abnormal pressure in hydrocarbon environments

    USGS Publications Warehouse

    Law, B.E.; Spencer, C.W.

    1998-01-01

    Abnormal pressures, pressures above or below hydrostatic pressures, occur on all continents in a wide range of geological conditions. According to a survey of published literature on abnormal pressures, compaction disequilibrium and hydrocarbon generation are the two most commonly cited causes of abnormally high pressure in petroleum provinces. In young (Tertiary) deltaic sequences, compaction disequilibrium is the dominant cause of abnormal pressure. In older (pre-Tertiary) lithified rocks, hydrocarbon generation, aquathermal expansion, and tectonics are most often cited as the causes of abnormal pressure. The association of abnormal pressures with hydrocarbon accumulations is statistically significant. Within abnormally pressured reservoirs, empirical evidence indicates that the bulk of economically recoverable oil and gas occurs in reservoirs with pressure gradients less than 0.75 psi/ft (17.4 kPa/m) and there is very little production potential from reservoirs that exceed 0.85 psi/ft (19.6 kPa/m). Abnormally pressured rocks are also commonly associated with unconventional gas accumulations where the pressuring phase is gas of either a thermal or microbial origin. In underpressured, thermally mature rocks, the affected reservoirs have most often experienced a significant cooling history and probably evolved from an originally overpressured system.

  4. Novel resorbable glass-ceramic scaffolds for hard tissue engineering: from the parent phosphate glass to its bone-like macroporous derivatives.

    PubMed

    Bretcanu, Oana; Baino, Francesco; Verné, Enrica; Vitale-Brovarone, Chiara

    2014-05-01

    One of the major challenges of hard tissue engineering research focuses on the development of scaffolds that can match the mechanical properties of the host bone and resorb at the same rate as the bone is repaired. The aim of this work was the synthesis and characterization of a resorbable phosphate glass, as well as its application for the fabrication of three dimensional (3-D) scaffolds for bone regeneration. The glass microstructure and behaviour upon heating were analysed by X-ray diffraction, differential scanning calorimetry and hot stage microscopy. The glass solubility was investigated according to relevant ISO standards using distilled water, simulated body fluid (SBF) and Tris-HCl as testing media. The glass underwent progressive dissolution over time in all three media but the formation of a hydroxyapatite-like layer was also observed on the samples soaked in SBF and Tris-HCl, which demonstrated the bioactivity of the material. The glass powder was used to fabricate 3-D macroporous bone-like glass-ceramic scaffolds by adopting polyethylene particles as pore formers: during thermal treatment, the polymer additive was removed and the sintering of glass particles was allowed. The obtained scaffolds exhibited high porosity (87 vol.%) and compressive strength around 1.5 MPa. After soaking for 4 months in SBF, the scaffolds mass loss was 76 wt.% and the pH of the solution did not exceed the 7.55 value, thereby remaining in a physiological range. The produced scaffolds, being resorbable, bioactive, architecturally similar to trabecular bone and exhibiting interesting mechanical properties, can be proposed as promising candidates for bone repair applications.

  5. Multitracer Study of Flow to Tile Drains in Irrigated Macroporous Soil

    NASA Astrophysics Data System (ADS)

    Bishop, J. M.; Callaghan, M. V.; Cey, E.; Bentley, L. R.

    2010-12-01

    analysis showed that the tiles are highly affected by the lateral and vertical contributions to the drains. Distribution of the DFBA in the soil showed that 82% of the tracer remained in the top 75 cm of the soil profile at the end of the 2009 season. This indicates that macropore flow is occurring, but has a minor influence on the movement of the salt mass. This result is important because it illustrates that although the salt mass has migrated slowly, macroporosity can transport contaminants quickly enough to exceeded drinking water quality guidelines. Breakthrough of the PFBA occurred in the north tile drain 13 hrs after application and peaked at a concentration of 10 mg/L, followed by a sharp decrease and stabilization to concentrations of 1.0 mg/L. This shows that macropore flow is occurring at depth in addition to the surface and that contaminant transport can occur rapidly in soils with lower hydraulic conductivity. Salt concentrations in the effluent were measured at high concentrations, showing that effective salt flushing of the matrix is still occurring.

  6. 3D structure of macropore networks within natural and de-embarked estuary saltmarsh sediments: towards an improved understanding of network structural control over hydrologic function

    NASA Astrophysics Data System (ADS)

    Carr, Simon; Spencer, Kate; James, Tempest; Lucy, Diggens

    2015-04-01

    Saltmarshes are globally important environments which, though occupying < 4% of the Earth's surface, provide a range of ecosystem services. Yet, they are threatened by sea level rise, human population growth, urbanization and pollution resulting in degradation. To compensate for this habitat loss many coastal restoration projects have been implemented over the last few decades, largely driven by legislative requirements for improved biodiversity e.g. the EU Habitats Directive and Birds Directive. However, there is growing evidence that restored saltmarshes, recreated through the return to tidal inundation of previously drained and defended low-lying coastal land, do not have the same species composition even after 100 years and while environmental enhancement has been achieved, there may be consequences for ecosystem functioning This study presents the findings of a comparative analysis of detailed sediment structure and hydrological functioning of equivalent natural and de-embanked saltmarsh sediments at Orplands Farm, Essex, UK. 3D x-ray CT scanning of triplicate undisturbed sediment cores recovered in 2013 have been used to derive detailed volumetric reconstructions of macropore structure and networks, and to infer differences in bulk microporosity between natural and de-embanked saltmarshes. These volumes have been further visualised for qualitative analysis of the main sediment components, and extraction of key macropore space parameters for quantified analysis including total porosity and connectivity, as well as structure, organisation and efficiency (tortuosity) of macropore networks. Although total porosity was significantly greater within the de-embanked saltmarsh sediments, pore networks in these samples were less organised and more tortuous, and were also inferred to have significantly lower micro-porosity than those of the natural saltmarsh. These datasets are applied to explain significant differences in the hydraulic behaviour and functioning

  7. Three-Dimensional Printing of Hollow-Struts-Packed Bioceramic Scaffolds for Bone Regeneration.

    PubMed

    Luo, Yongxiang; Zhai, Dong; Huan, Zhiguang; Zhu, Haibo; Xia, Lunguo; Chang, Jiang; Wu, Chengtie

    2015-11-04

    Three-dimensional printing technologies have shown distinct advantages to create porous scaffolds with designed macropores for application in bone tissue engineering. However, until now, 3D-printed bioceramic scaffolds only possessing a single type of macropore have been reported. Generally, those scaffolds with a single type of macropore have relatively low porosity and pore surfaces, limited delivery of oxygen and nutrition to surviving cells, and new bone tissue formation in the center of the scaffolds. Therefore, in this work, we present a useful and facile method for preparing hollow-struts-packed (HSP) bioceramic scaffolds with designed macropores and multioriented hollow channels via a modified coaxial 3D printing strategy. The prepared HSP scaffolds combined high porosity and surface area with impressive mechanical strength. The unique hollow-struts structures of bioceramic scaffolds significantly improved cell attachment and proliferation and further promoted formation of new bone tissue in the center of the scaffolds, indicating that HSP ceramic scaffolds can be used for regeneration of large bone defects. In addition, the strategy can be used to prepare other HSP ceramic scaffolds, indicating a universal application for tissue engineering, mechanical engineering, catalysis, and environmental materials.

  8. The elusive abnormal CO2 insertion enabled by metal-ligand cooperative photochemical selectivity inversion.

    PubMed

    Schneck, Felix; Ahrens, Jennifer; Finger, Markus; Stückl, A Claudia; Würtele, Christian; Schwarzer, Dirk; Schneider, Sven

    2018-03-21

    Direct hydrogenation of CO 2 to CO, the reverse water-gas shift reaction, is an attractive route to CO 2 utilization. However, the use of molecular catalysts is impeded by the general reactivity of metal hydrides with CO 2 . Insertion into M-H bonds results in formates (MO(O)CH), whereas the abnormal insertion to the hydroxycarbonyl isomer (MC(O)OH), which is the key intermediate for CO-selective catalysis, has never been directly observed. We here report that the selectivity of CO 2 insertion into a Ni-H bond can be inverted from normal to abnormal insertion upon switching from thermal to photochemical conditions. Mechanistic examination for abnormal insertion indicates photochemical N-H reductive elimination as the pivotal step that leads to an umpolung of the hydride ligand. This study conceptually introduces metal-ligand cooperation for selectivity control in photochemical transformations.

  9. Mutant laboratory mice with abnormalities in hair follicle morphogenesis, cycling, and/or structure: an update.

    PubMed

    Nakamura, Motonobu; Schneider, Marlon R; Schmidt-Ullrich, Ruth; Paus, Ralf

    2013-01-01

    Human hair disorders comprise a number of different types of alopecia, atrichia, hypotrichosis, distinct hair shaft disorders as well as hirsutism and hypertrichosis. Their causes vary from genodermatoses (e.g. hypotrichoses) via immunological disorders (e.g. alopecia areata, autoimmune cicatrical alopecias) to hormone-dependent abnormalities (e.g. androgenetic alopecia). A large number of spontaneous mouse mutants and genetically engineered mice develop abnormalities in hair follicle morphogenesis, cycling, and/or hair shaft formation, whose analysis has proven invaluable to define the molecular regulation of hair growth, ranging from hair follicle development, and cycling to hair shaft formation and stem cell biology. Also, the accumulating reports on hair phenotypes of mouse strains provide important pointers to better understand the molecular mechanisms underlying human hair growth disorders. Since numerous new mouse mutants with a hair phenotype have been reported since the publication of our earlier review on this matter a decade ago, we present here an updated, tabulated mini-review. The updated annotated tables list a wide selection of mouse mutants with hair growth abnormalities, classified into four categories: Mutations that affect hair follicle (1) morphogenesis, (2) cycling, (3) structure, and (4) mutations that induce extrafollicular events (for example immune system defects) resulting in secondary hair growth abnormalities. This synthesis is intended to provide a useful source of reference when studying the molecular controls of hair follicle growth and differentiation, and whenever the hair phenotypes of a newly generated mouse mutant need to be compared with existing ones. Copyright © 2012 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  10. Preliminary enrichment and separation of chlorogenic acid from Helianthus tuberosus L. leaves extract by macroporous resins.

    PubMed

    Sun, Peng-Cheng; Liu, Ying; Yi, Yue-Tao; Li, Hong-Juan; Fan, Ping; Xia, Chuan-Hai

    2015-02-01

    In the present study, a simple and efficient method for the preparative separation of 3-CQA from the extract of Helianthus tuberosus leaves with macroporous resins was studied. ADS-21 showed much higher adsorption capacity and better adsorption/desorption properties for 3-CQA among the tested resins. The adsorption of 3-CQA on ADS-21 resin at 25°C was fitted best to the Langmuir isotherm model and pseudo-second-order kinetic model. Dynamic adsorption/desorption experiments were carried out in a glass column packed with ADS-21 to optimise the separation process of 3-CQA from H. tuberosus leaves extract. After one treatment with ADS-21, the content of 3-CQA in the product was increased 5.42-fold, from 12.0% to 65.2%, with a recovery yield of 89.4%. The results demonstrated that the method was suitable for large-scale separation and manufacture of 3-CQA from H. tuberosus leaves. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Photonic molecules for improving the optical response of macroporous silicon photonic crystals for gas sensing purposes.

    PubMed

    Cardador, D; Segura, D; Rodríguez, A

    2018-02-19

    In this paper, we report the benefits of working with photonic molecules in macroporous silicon photonic crystals. In particular, we theoretically and experimentally demonstrate that the optical properties of a resonant peak produced by a single photonic atom of 2.6 µm wide can be sequentially improved if a second and a third cavity of the same length are introduced in the structure. As a consequence of that, the base of the peak is reduced from 500 nm to 100 nm, while its amplitude remains constant, increasing its Q-factor from its initial value of 25 up to 175. In addition, the bandgap is enlarged almost twice and the noise within it is mostly eliminated. In this study we also provide a way of reducing the amplitude of one or two peaks, depending whether we are in the two- or three-cavity case, by modifying the length of the involved photonic molecules so that the remainder can be used to measure gas by spectroscopic methods.

  12. Electrocardiographic abnormalities in opiate addicts.

    PubMed

    Wallner, Christina; Stöllberger, Claudia; Hlavin, Anton; Finsterer, Josef; Hager, Isabella; Hermann, Peter

    2008-12-01

    To determine in a cross-sectional study the prevalence of electrocardiographic (ECG) abnormalities in opiate addicts who were therapy-seeking and its association with demographic, clinical and drug-specific parameters. In consecutive therapy-seeking opiate addicts, a 12-lead ECG was registered within 24 hours after admission and evaluated according to a pre-set protocol between October 2004 and August 2006. Additionally, demographic, clinical and drug-specific parameters were recorded. Included were 511 opiate-addicts, 25% female, with a mean age of 29 years (range 17-59 years). One or more ECG abnormalities were found in 314 patients (61%). In the 511 patients we found most commonly ST abnormalities (19%), QTc prolongation (13%), tall R- and/or S-waves (11%) and missing R progression (10%). ECG abnormalities were more common in males than in females (64 versus 54%, P < 0.05), and in patients with positive than negative urine findings for cannabis (68 versus 57%, P < 0.05). Patients with ST abnormalities were more often males than females (21 versus 11%, P < 0.05), had a history of seizures less often (16 versus 27%, P < 0.05), had positive than negative urine findings for cannabis more often (26 versus 15%, P < 0.01) and had negative than positive urine findings for methadone more often (21 versus 11%, P < 0.05). QTc prolongation was more frequent in patients with high dosages of maintenance drugs than in patients with medium or low dosages (27 versus 12 versus 10%, P < 0.05) and in patients whose urine findings were positive than negative for methadone (23 versus 11%, P < 0.001) as well as for benzodiazepines (17 versus 9%, P < 0.05). Limitations of the data are that in most cases other risk factors for the cardiac abnormalities were not known. ECG abnormalities are frequent in opiate addicts. The most frequent ECG abnormalities are ST abnormalities, QTc prolongation and tall R- and/or S-waves. ST abnormalities are associated with cannabis, and QTc prolongation

  13. Metabolic differentiation and classification of abnormal Savda Munziq's pharmacodynamic role on rat models with different diseases by nuclear magnetic resonance-based metabonomics.

    PubMed

    Mamtimin, Batur; Xia, Guo; Mijit, Mahmut; Hizbulla, Mawlanjan; Kurbantay, Nazuk; You, Li; Upur, Halmurat

    2015-01-01

    Abnormal Savda Munziq (ASMq) is a traditional Uyghur herbal preparation used as a therapy for abnormal Savda-related diseases. In this study, we investigate ASMq's dynamic effects on abnormal Savda rat models under different disease conditions. Abnormal Savda rat models with hepatocellular carcinoma (HCC), type 2 diabetes mellitus (T2DM), and asthma dosed of ASMq. Serum samples of each animal tested by nuclear magnetic resonance spectroscopy and analyzed by orthogonal projection to latent structure with discriminant analysis. Compared with healthy controls, HCC rats had higher concentrations of amino acids, fat-related metabolites, lactate, myoinositol, and citrate, but lower concentrations of α-glucose, β-glucose, and glutamine. Following ASMq treatment, the serum acetone very low-density lipoprotein (VLDL), LDL, unsaturated lipids, acetylcysteine, and pyruvate concentration decreased, but α-glucose, β-glucose, and glutamine concentration increased (P < 0.05). T2DM rats had higher concentrations of α- and β-glucose, but lower concentrations of isoleucine, leucine, valine, glutamine, glycoprotein, lactate, tyrosine, creatine, alanine, carnitine, and phenylalanine. After ASMq treated T2DM groups showed reduced α- and β-glucose and increased creatine levels (P < 0.05). Asthma rats had higher acetate, carnitine, formate, and phenylalanine levels, but lower concentrations of glutamine, glycoprotein, lactate, VLDL, LDL, and unsaturated lipids. ASMq treatment showed increased glutamine and reduced carnitine, glycoprotein, formate, and phenylalanine levels (P < 0.05). Low immune function, decreased oxidative defense, liver function abnormalities, amino acid deficiencies, and energy metabolism disorders are common characteristics of abnormal Savda-related diseases. ASMq may improve the abnormal metabolism and immune function of rat models with different diseases combined abnormal Savda.

  14. Highly Bactericidal Macroporous Antimicrobial Polymeric Gel for Point-of-Use Water Disinfection.

    PubMed

    Kumar, Amit; Boyer, Cyrille; Nebhani, Leena; Wong, Edgar H H

    2018-05-21

    Access to clean and safe water supply remains inadequate in many developing countries. One of the key challenges is to remove pathogenic bacteria from the water supply via effective water disinfection technologies to prevent the spread of diseases and to ensure the safety of consumers. Herein, a highly effective point-of-use (on-demand) water disinfection technology, in the form of a polymeric scaffold called macroporous antimicrobial polymeric gel (MAPG), is demonstrated. MAPG is easy to fabricate, completely organic and possess inherent antimicrobial property which makes it non-reliant on inorganic compounds such as silver where the long-term toxicity remains unknown. MAPG is highly bactericidal and can disinfect bacteria-contaminated water (ca. 10 8  CFU mL -1 ) at a capacity of about >50 times the mass of the organic material used, inactivating >99% of both Gram-negative and Gram-positive bacteria including Escherichia coli, Vibrio cholerae and Staphylococcus aureus within 20 minutes of treatment. When fabricated in a syringe, MAPG eliminates E. coli from contaminated water source by >8.0 log 10 reduction in bacteria counts (i.e., no viable bacteria were detected after treatment), and the syringe can be reused multiple times without losing potency. The MAPG technology is not only restricted to water disinfection but may also be applicable in other bacteria inactivation applications.

  15. Biochemical abnormalities in neonatal seizures.

    PubMed

    Sood, Arvind; Grover, Neelam; Sharma, Roshan

    2003-03-01

    The presence of seizure does not constitute a diagnoses but it is a symptom of an underlying central nervous system disorder due to systemic or biochemical disturbances. Biochemical disturbances occur frequently in the neonatal seizures either as an underlying cause or as an associated abnormality. In their presence, it is difficult to control seizure and there is a risk of further brain damage. Early recognition and treatment of biochemical disturbances is essential for optimal management and satisfactory long term outcome. The present study was conducted in the department of pediatrics in IGMC Shimla on 59 neonates. Biochemical abnormalities were detected in 29 (49.15%) of cases. Primary metabolic abnormalities occurred in 10(16.94%) cases of neonatal seizures, most common being hypocalcaemia followed by hypoglycemia, other metabolic abnormalities include hypomagnesaemia and hyponateremia. Biochemical abnormalities were seen in 19(38.77%) cases of non metabolic seizure in neonates. Associated metabolic abnormalities were observed more often with Hypoxic-ischemic-encephalopathy (11 out of 19) cases and hypoglycemia was most common in this group. No infant had hyponateremia, hyperkelemia or low zinc level.

  16. Immobilization of pectinase and lipase on macroporous resin coated with chitosan for treatment of whitewater from papermaking.

    PubMed

    Liu, Kai; Zhao, Guanglei; He, Beihai; Chen, Lihui; Huang, Liulian

    2012-11-01

    Anionic residues and pitch deposits in whitewater negatively impact the operation of paper-forming equipment. In order to remove these substances, a macroporous resin based on a methyl acrylate matrix was synthesized and coated with chitosan of various molecular weights through glutaraldehyde cross-linking. Pectinase from Bacillus licheniformis and lipase from Thermomyces lanuginosus were immobilized on the resin coated with chitosan by a Schiff base reaction. The highest hydrolysis activities of the immobilized enzymes were achieved by using chitosan with 10×10(5)DaMW for coating and 0.0025% glutaraldehyde for cross-linking chitosan. The cationic demand and pitch deposits in whitewater were reduced by 58% and 74%, respectively, when treating whitewater with immobilized dual-enzymes for 15min at 55°C and pH 7.5. This method is useful for treatment of whitewater in the papermaking industry. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Chorionic villus sampling for abnormal screening compared to historical indications: prevalence of abnormal karyotypes.

    PubMed

    Marshall, Nicole E; Fraley, Gwen; Feist, Cori; Burns, Michael J; Pereira, Leonardo

    2012-08-01

    To determine the prevalence of abnormal karyotype results in women undergoing chorionic villus sampling (CVS) for abnormal first trimester screening compared to CVS for historical indications (advanced maternal age (AMA) or prior aneuploidy). Retrospective cohort of all patients undergoing CVS at Oregon Health & Science University from January 2006 to June 2010. Patients were separated based on CVS indication: (1) positive ultrasound (U/S) or serum screening; or (2) AMA or prior aneuploidy with normal or no screening. Prevalence of abnormal karyotype results were compared between groups. Fetal karyotyping was successful in 500 of 506 CVS procedures performed. 203 CVS were performed for positive screening with 69 abnormal karyotypes (34.0%). 264 CVS were performed for historical indications with 11 abnormal karyotypes (4.2%). This difference was statistically significant (χ(2) 71.9, p < 0.001; OR 11.8 [95% CI 5.8, 24.6]). There were two age-related aneuplodies in AMA women without positive screening. 42 out of 44 AMA women diagnosed with aneuploidy (95.5%) had abnormal U/S and/or serum screening (35 U/S, 4 serum, 3 U/S and serum). Combined ultrasound and serum screening should be recommended to all women, including AMA women, prior to undergoing invasive testing to improve risk-based counseling and minimize morbidity.

  18. Visual scan paths are abnormal in deluded schizophrenics.

    PubMed

    Phillips, M L; David, A S

    1997-01-01

    One explanation for delusion formation is that they result from distorted appreciation of complex stimuli. The study investigated delusions in schizophrenia using a physiological marker of visual attention and information processing, the visual scan path-a map tracing the direction and duration of gaze when an individual views a stimulus. The aim was to demonstrate the presence of a specific deficit in processing meaningful stimuli (e.g. human faces) in deluded schizophrenics (DS) by relating this to abnormal viewing strategies. Visual scan paths were measured in acutely-deluded (n = 7) and non-deluded (n = 7) schizophrenics matched for medication, illness duration and negative symptoms, plus 10 age-matched normal controls. DS employed abnormal strategies for viewing single faces and face pairs in a recognition task, staring at fewer points and fixating non-feature areas to a significantly greater extent than both control groups (P < 0.05). The results indicate that DS direct their attention to less salient visual information when viewing faces. Future paradigms employing more complex stimuli and testing DS when less-deluded will allow further clarification of the relationship between viewing strategies and delusions.

  19. Temporal lobe developmental malformations and epilepsy: dual pathology and bilateral hippocampal abnormalities.

    PubMed

    Ho, S S; Kuzniecky, R I; Gilliam, F; Faught, E; Morawetz, R

    1998-03-01

    Temporal lobe developmental malformations (TLDM) with focal cortical dysplasia and balloon cells may coexist with mesial temporal sclerosis. The true incidence of this dual pathology is unknown. Our aim was to assess the frequency of amygdala (AM)-hippocampal abnormality in a homogeneous population with this specific developmental malformation. MRI-based volumetry of the AM and hippocampal formation (HF) in 30 patients with unilateral TLDM and intractable partial epilepsy was performed. A volume normalization process defined a normal range of HF and AM volumes in control subjects, and enabled the detection of bilateral volume loss. Normalized volumes detected HF atrophy in 26 patients (nine unilateral and 17 bilateral) and AM atrophy in 18 patients (three unilateral and 15 bilateral). Visual analysis detected unilateral HF abnormality in 21 patients and bilateral abnormality in two. When compared with a group of patients with temporal lobe epilepsy and pure hippocampal sclerosis (N = 92), where volumetry revealed bilateral HF atrophy in 18%, a significant difference in the frequency of bilateral HF atrophy was found (p < 0.0001). Dual pathology is frequent in patients with TLDM (87%), and the AM-HF abnormality is often bilateral (57%). Our data suggest that more widespread and potentially epileptogenic lesions coexist with visibly detectable unilateral TLDM. This has implications for the selection of patients for temporal lobe surgery and may influence surgical strategies.

  20. Chromosomal abnormalities in human sperm

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

    Martin, R.H.

    1985-01-01

    The ability to analyze human sperm chromosome complements after penetration of zona pellucida-free hamster eggs provides the first opportunity to study the frequency and type of chromosomal abnormalities in human gametes. Two large-scale studies have provided information on normal men. We have studied 1,426 sperm complements from 45 normal men and found an abnormality rate of 8.9%. Brandriff et al. (5) found 8.1% abnormal complements in 909 sperm from 4 men. The distribution of numerical and structural abnormalities was markedly dissimilar in the 2 studies. The frequency of aneuploidy was 5% in our sample and only 1.6% in Brandriff's, perhapsmore » reflecting individual variability among donors. The frequency of 24,YY sperm was low: 0/1,426 and 1/909. This suggests that the estimates of nondisjunction based on fluorescent Y body data (1% to 5%) are not accurate. We have also studied men at increased risk of sperm chromosomal abnormalities. The frequency of chromosomally unbalanced sperm in 6 men heterozygous for structural abnormalities varied dramatically: 77% for t11;22, 32% for t6;14, 19% for t5;18, 13% for t14;21, and 0% for inv 3 and 7. We have also studied 13 cancer patients before and after radiotherapy and demonstrated a significant dose-dependent increase of sperm chromosome abnormalities (numerical and structural) 36 months after radiation treatment.« less

  1. Enrichment and Purification of Total Ginkgo Flavonoid O-Glycosides from Ginkgo Biloba Extract with Macroporous Resin and Evaluation of Anti-Inflammation Activities In Vitro.

    PubMed

    Zhang, Lihu; Wu, Tingting; Xiao, Wei; Wang, Zhenzhong; Ding, Gang; Zhao, Linguo

    2018-05-13

    In the present study, the performance and separation characteristics of six macroporous resins for the enrichment and purification of total ginkgo flavonoid O -glycosides (TGFs) (quercetin (I), kaempferol (II), isorhamnetin (III)) from Ginkgo Biloba extracts (EGB) are evaluated. The adsorption and desorption properties of TGFs are studied on macroporous resins, including D101, D201, AB-8, HPD400, D301, and D311. Along with the results, AB-8 resin exhibits the best adsorption and desorption capacity for these three ginkgo flavonoid O -glycosides among the six resins. Adsorption isotherms are created on AB-8 resin and fit well to the Langmuir (R² > 0.96) and Freundlich (R² > 0.92, 0.3 < 1/n < 0.7) models. After the treatment with gradient elution on AB-8 resin packed chromatography column, the contents of the three main ginkgo flavonoid O -glycosides (I, II, and III) increase from 8.93%, 9.88%, and 6.11% in the extracts to 30.12%, 35.21%, and 14.14%, respectively, in the product. The recoveries of compounds I, II, and III are 88.76%, 93.78%, and 60.90%, respectively. Additionally, the anti-inflammatory effects of TGFs are evaluated in LPS-treated RAW 264.7 macrophages, and the result demonstrates that TGFs could significantly inhibit LPS-induced NO release in vitro in a dose-dependent manner compared with the control group. These findings suggest that TGFs could potentially be natural antioxidants and anti-inflammatory ingredients that could be used in pharmaceutical products and functional food additives.

  2. An experimental investigation to characterise soil macroporosity under different land use and land covers of northeast India

    NASA Astrophysics Data System (ADS)

    Shougrakpam, Sangeeta; Sarkar, Rupak; Dutta, Subashisa

    2010-10-01

    Saturated macropore flow is the dominant hydrological process in tropical and subtropical hilly watersheds of northeast India. The process of infiltration into saturated macroporous soils is primarily controlled by size, network, density, connectivity, saturation of surrounding soil matrix, and depthwise distribution of macropores. To understand the effects of local land use, land cover and management practices on soil macroporosity, colour dye infiltration experiments were conducted with ten soil columns (25 × 25 × 50 cm) collected from different watersheds of the region under similar soil and agro-climatic zones. The sampling sites included two undisturbed forested hillslopes, two conventionally cultivated paddy fields, two forest lands abandoned after Jhum cultivation, and two paddy fields, one pineapple plot and one banana plot presently under active cultivation stage of the Jhum cycle. Digital image analyses of the obtained dye patterns showed that the infiltration patterns differed significantly for different sites with varying land use, land cover, and cultivation practices. Undisturbed forest soils showed high degree of soil macroporosity throughout the soil profile, paddy fields revealed sealing of macropores at the topsoil due to hard pan formation, and Jhum cultivated plots showed disconnected subsoil macropores. The important parameters related to soil macropores such as maximum and average size of macropores, number of active macropores, and depthwise distribution of macropores were estimated to characterise the soil macroporosity for the sites. These experimentally derived quantitative data of soil macroporosity can have wide range of applications in the region such as water quality monitoring and groundwater pollution assessment due to preferential leaching of solutes and pesticides, study of soil structural properties and infiltration behaviour of soils, investigation of flash floods in rivers, and hydrological modelling of the watersheds.

  3. Use of abnormal and health psychology as topics in a classroom format to reduce alcohol and other drug abuse among college students at risk.

    PubMed

    Miley, W M

    2001-12-01

    This study was done to assess whether classes containing topics derived from two college courses, Abnormal Psychology and Health Psychology, could be used in a class room format to reduce alcohol and other drug abuse among at-risk college students. Topics covered included stress and stress management, alcohol and other drug use and abuse, chronic illnesses and psychological disorders that develop from an unhealthy lifestyle, and factors that play a role in good health and well-being. Students were enrolled in a semester-long course for college credit as an alternative to punitive sanctions for on-campus alcohol violations and other drug violations. The Midwest Institute on Drug Use Survey and the CORE Alcohol and Drug Survey were administered on the first and last days of class. Analysis indicated a significant self-reported reduction in drug use and associated negative symptoms and behavioral effects. Women were more likely to report reductions in drug use than men.

  4. Arsenite promotes centrosome abnormalities under a p53 compromised status induced by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)

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

    Liao, W.-T.; Center of Excellence for Environmental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Graduate Institute of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan

    2010-02-15

    Epidemiological evidence indicated that residents, especially cigarette smokers, in arseniasis areas had significantly higher lung cancer risk than those living in non-arseniasis areas. Thus an interaction between arsenite and cigarette smoking in lung carcinogenesis was suspected. In the present study, we investigated the interactions of a tobacco-specific carcinogen 4- (methylnitrosamino)-1-(3-pyridyl)-1-butanone (nicotine-derived nitrosamine ketone, NNK) and arsenite on lung cell transformation. BEAS-2B, an immortalized human lung epithelial cell line, was selected to test the centrosomal abnormalities and colony formation by NNK and arsenite. We found that NNK, alone, could enhance BEAS-2B cell growth at 1-5 muM. Under NNK exposure, arsenite wasmore » able to increase centrosomal abnormality as compared with NNK or arsenite treatment alone. NNK treatment could also reduce arsenite-induced G2/M cell cycle arrest and apoptosis, these cellular effects were found to be correlated with p53 dysfunction. Increased anchorage-independent growth (colony formation) of BEAS-2B cells cotreated with NNK and arsenite was also observed in soft agar. Our present investigation demonstrated that NNK could provide a p53 compromised status. Arsenite would act specifically on this p53 compromised status to induce centrosomal abnormality and colony formation. These findings provided strong evidence on the carcinogenic promotional role of arsenite under tobacco-specific carcinogen co-exposure.« less

  5. Association of abnormal morphology and altered gene expression in human preimplantation embryos.

    PubMed

    Wells, Dagan; Bermúdez, Mercedes G; Steuerwald, Nury; Malter, Henry E; Thornhill, Alan R; Cohen, Jacques

    2005-08-01

    We set out to characterize the expression of nine genes in human preimplantation embryos and determine whether abnormal morphology is associated with altered gene activity. Reverse transcription and real-time polymerase chain reaction were used to quantify the expression of multiple genes in each embryo. The genes studied have various important cellular roles (e.g., cell cycle regulation, DNA repair, and apoptosis). Research laboratory working closely with a clinical IVF practice. Over 50 embryos were donated by infertile patients (various etiologies). Among these, all major stages of preimplantation development and a variety of common morphologic abnormalities were represented. None. Quantification of mRNA transcripts. We detected an association between certain forms of abnormal morphology and disturbances of gene activity. Cellular fragmentation was associated with altered expression of several genes, including TP53, suggesting that fragmenting blastomeres are suffering stress of a type monitored by p53, possibly as a consequence of suboptimal culture conditions. Appropriate gene expression is vital for the regulation of metabolic pathways and key developmental events. Our data indicates a possible causal relationship between changes in gene expression and the formation of clinically relevant abnormal embryo morphologies. We hypothesize that embryos with expression profiles characteristic of good morphology and appropriate for their developmental stage have the greatest potential for implantation. If confirmed, this could lead to a new generation of preimplantation genetic diagnosis (PGD) tests for assessing embryo viability and predicting implantation potential.

  6. Abnormal formation velocities and applications to pore pressure prediction

    NASA Astrophysics Data System (ADS)

    Liu, Libin; Shen, Guoqiang; Wang, Zhentao; Yang, Hongwei; Han, Hongwei; Cheng, Yuanfeng

    2018-06-01

    The pore pressure is a vital concept to the petroleum industry and cannot be ignored by either reservoir engineers or geoscientists. Based on theoretical analyses of effective stresses and the grain packing model, a new equation is proposed for predicting pore pressures from formation velocity data. The predictions agree well with both measured pressures and estimations using Eaton's empirical equation, but the application of the new equation to seismic data is simple and convenient. One application example shows that the identification of sweet spots is much easier using pore pressure data than with inverted seismic velocity data. In another application example using field seismic data, a distribution of overpressured strata is revealed, which is a crucial clue for petroleum generation and accumulation. Still, the accuracy of pore pressure prediction is hardly always guaranteed, mainly owing to the complexity of the real geology and the suitability of specific assumptions about the underlying rock physics.

  7. Macroporous graphitic carbon foam decorated with polydopamine as a high-performance anode for microbial fuel cell

    NASA Astrophysics Data System (ADS)

    Jiang, Hongmei; Yang, Lu; Deng, Wenfang; Tan, Yueming; Xie, Qingji

    2017-09-01

    Herein, a macroporous graphitic carbon foam (MGCF) electrode decorated with polydopamine (PDA) is used as a high-performance anode for microbial fuel cell (MFC) applications. The MGCF is facilely prepared by pyrolysis of a powder mixture comprising maltose, nickel nitrate, and ammonia chloride, without using solid porous template. The MGCF is coated with PDA by self-polymerization of dopamine in a basic solution. The MGCF can provide a large surface area for bacterial attachment, and PDA coated on the MGCF electrode can further promote bacterial adhesion resulting from the improved hydrophility, so the MGCF-PDA electrode as an anode in a MFC can show ultrahigh bacterial loading capacity. Moreover, the electrochemical oxidation of flavins at the MGCF-PDA electrode is greatly accelerated, so the extracellular electron transfer mediated by flavins is improved. As a result, the MFC equipped with a MGCF-PDA anode can show a maximum power density of 1735 mW cm-2, which is 6.7 times that of a MFC equipped with a commercial carbon felt anode, indicating a promising anode for MFC applications.

  8. Template-free synthesis of renewable macroporous carbon via yeast cells for high-performance supercapacitor electrode materials.

    PubMed

    Sun, Hongmei; He, Wenhui; Zong, Chenghua; Lu, Lehui

    2013-03-01

    The urgent need for sustainable development has forced material scientists to explore novel materials for next-generation energy storage devices through a green and facile strategy. In this context, yeast, which is a large group of single cell fungi widely distributed in nature environments, will be an ideal candidate for developing effective electrode materials with fascinating structures for high-performance supercapacitors. With this in mind, herein, we present the first example of creating three-dimensional (3D) interpenetrating macroporous carbon materials via a template-free method, using the green, renewable, and widespread yeast cells as the precursors. Remarkably, when the as-prepared materials are used as the electrode materials for supercapacitors, they exhibit outstanding performance with high specific capacitance of 330 F g(-1) at a current density of 1 A g(-1), and good stability, even after 1000 charge/discharge cycles. The approach developed in this work provides a new view of making full use of sustainable resources endowed by nature, opening the avenue to designing and producing robust materials with great promising applications in high-performance energy-storage devices.

  9. Selective removal of caffeine from tea extracts using macroporous crosslinked polyvinyl alcohol adsorbents.

    PubMed

    Ma, Ning; Wang, Peng; Kong, Xia; Shi, Rongfu; Yuan, Zhi; Wang, Chunhong

    2012-01-01

    The hydrolysis reaction of ester groups in vinyl acetate (VAc) was used to introduce hydroxyl groups into the matrix of a macroporous adsorbent, which was itself prepared by free radical suspension copolymerization of triallyl isocyanurate (TAIC) and VAc. Therefore, the copolymerization incompatibility between the hydrophilic and the hydrophobic monomer was overcome successfully and the hydrophobic matrix of the polymeric adsorbent containing a polyvinyl alcohol (PVA) segment was obtained. Introduction of the PVA segment decreased the hydrophobic adsorption affinity of the adsorbent while producing the hydrogen-bonding interaction. When isolating the two active components, polyphenols (TPh) and caffeine (CAF), from green tea extracts, this polymeric adsorbent, namely poly(TAIC-co-VA), exhibited good adsorption selectivity towards TPh over CAF. The adsorption mechanism leading to this selectivity involved a hydrophobic interaction mechanism for CAF and multiple weak hydrophobic and hydrogen-bonding interactions for TPh. The adsorption thermodynamics for TPh on poly(TAIC-co-VA) were studied. The effects of adsorbent structure and gradient desorption conditions on isolation were investigated. The result showed that adsorbent, with 20% TAIC content, was able to efficiently remove CAF from different tea extracts with different ratios of TPh and CAF. Finally, almost no CAF was detected in the TPh fraction and the recovery of TPh was greater than 95%. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Gamma-tubulin-containing abnormal centrioles are induced by insufficient Plk4 in human HCT116 colorectal cancer cells.

    PubMed

    Kuriyama, Ryoko; Bettencourt-Dias, Monica; Hoffmann, Ingrid; Arnold, Marc; Sandvig, Lisa

    2009-06-15

    Cancer cells frequently induce aberrant centrosomes, which have been implicated in cancer initiation and progression. Human colorectal cancer cells, HCT116, contain aberrant centrioles composed of disorganized cylindrical microtubules and displaced appendages. These cells also express unique centrosome-related structures associated with a subset of centrosomal components, including gamma-tubulin, centrin and PCM1. During hydroxyurea treatment, these abnormal structures become more abundant and undergo a change in shape from small dots to elongated fibers. Although gamma-tubulin seems to exist as a ring complex, the abnormal structures do not support microtubule nucleation. Several lines of evidence suggest that the fibers correspond to a disorganized form of centriolar microtubules. Plk4, a mammalian homolog of ZYG-1 essential for initiation of centriole biogenesis, is not associated with the gamma-tubulin-specific abnormal centrosomes. The amount of Plk4 at each centrosome was less in cells with abnormal centrosomes than cells without gamma-tubulin-specific abnormal centrosomes. In addition, the formation of abnormal structures was abolished by expression of exogenous Plk4, but not SAS6 and Cep135/Bld10p, which are downstream regulators required for the organization of nine-triplet microtubules. These results suggest that HCT116 cells fail to organize the ninefold symmetry of centrioles due to insufficient Plk4.

  11. Abnormal Eye Movements in Creutzfeldt-Jakob Disease

    NASA Technical Reports Server (NTRS)

    Grant, Michael P.; Cohen, Mark; Petersen, Robert B.; Halmagyi, G. Michael; McDougall, Alan; Tusa, Ronald J.; Leigh, R. John

    1993-01-01

    We report 3 patients with autopsy-proven Creutzfeldt-Jakob disease who, early in their course, developed abnormal eye movements that included periodic alternating nystagmus and slow vertical saccades. These findings suggested involvement of the cerebellar nodulus and uvula, and the brainstem reticular formation, respectively. Cerebellar ataxia was also an early manifestation and, in one patient, a frontal lobe brain biopsy was normal at a time when ocular motor and cerebellar signs were conspicuous. As the disease progressed, all saccades and quick phases of nystagmus were lost, but periodic alternating gaze deviation persisted. At autopsy, 2 of the 3 patients had pronounced involvement of the cerebellum, especially of the midline structures. Creutzfeldt-Jakob disease should be considered in patients with subacute progressive neurological disease when cognitive changes are overshadowed by ocular motor findings or ataxia.

  12. A miniaturized microbial fuel cell with three-dimensional graphene macroporous scaffold anode demonstrating a record power density of over 10,000 W m(-3) .

    PubMed

    Ren, Hao; Tian, He; Gardner, Cameron L; Ren, Tian-Ling; Chae, Junseok

    2016-02-14

    A microbial fuel cell (MFC) is a bio-inspired renewable energy converter which directly converts biomass into electricity. This is accomplished via the unique extracellular electron transfer (EET) of a specific species of microbe called the exoelectrogen. Many studies have attempted to improve the power density of MFCs, yet the reported power density is still nearly two orders of magnitude lower than other power sources/converters. Such a low performance can primarily be attributed to two bottlenecks: (i) ineffective electron transfer from microbes located far from the anode and (ii) an insufficient buffer supply to the biofilm. This work takes a novel approach to mitigate these two bottlenecks by integrating a three-dimensional (3D) macroporous graphene scaffold anode in a miniaturized MFC. This implementation has delivered the highest power density reported to date in all MFCs of over 10,000 W m(-3). The miniaturized configuration offers a high surface area to volume ratio and improved mass transfer of biomass and buffers. The 3D graphene macroporous scaffold warrants investigation due to its high specific surface area, high porosity, and excellent conductivity and biocompatibility which facilitates EET and alleviates acidification in the biofilm. Consequently, the 3D scaffold houses an extremely thick and dense biofilm from the Geobacter-enriched culture, delivering an areal/volumetric current density of 15.51 A m(-2)/31,040 A m(-3) and a power density of 5.61 W m(-2)/11,220 W m(-3), a 3.3 fold increase when compared to its planar two-dimensional (2D) control counterparts.

  13. Neurologic abnormalities in murderers.

    PubMed

    Blake, P Y; Pincus, J H; Buckner, C

    1995-09-01

    Thirty-one individuals awaiting trial or sentencing for murder or undergoing an appeal process requested a neurologic examination through legal counsel. We attempted in each instance to obtain EEG, MRI or CT, and neuropsychological testing. Neurologic examination revealed evidence of "frontal" dysfunction in 20 (64.5%). There were symptoms or some other evidence of temporal lobe abnormality in nine (29%). We made a specific neurologic diagnosis in 20 individuals (64.5%), including borderline or full mental retardation (9) and cerebral palsy (2), among others. Neuropsychological testing revealed abnormalities in all subjects tested. There were EEG abnormalities in eight of the 20 subjects tested, consisting mainly of bilateral sharp waves with slowing. There were MRI or CT abnormalities in nine of the 19 subjects tested, consisting primarily of atrophy and white matter changes. Psychiatric diagnoses included paranoid schizophrenia (8), dissociative disorder (4), and depression (9). Virtually all subjects had paranoid ideas and misunderstood social situations. There was a documented history of profound, protracted physical abuse in 26 (83.8%) and of sexual abuse in 10 (32.3%). It is likely that prolonged, severe physical abuse, paranoia, and neurologic brain dysfunction interact to form the matrix of violent behavior.

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

    Bolotov, V. V.; Knyazev, E. V.; Ponomareva, I. V.

    The oxidation of mesoporous silicon in a double-layer “macroporous silicon–mesoporous silicon” structure is studied. The morphology and dielectric properties of the buried insulating layer are investigated using electron microscopy, ellipsometry, and electrical measurements. Specific defects (so-called spikes) are revealed between the oxidized macropore walls in macroporous silicon and the oxidation crossing fronts in mesoporous silicon. It is found that, at an initial porosity of mesoporous silicon of 60%, three-stage thermal oxidation leads to the formation of buried silicon-dioxide layers with an electric-field breakdown strength of E{sub br} ~ 10{sup 4}–10{sup 5} V/cm. Multilayered “porous silicon-on-insulator” structures are shown to bemore » promising for integrated chemical micro- and nanosensors.« less

  15. Triangle pore arrays fabricated on Si (111) substrate by sphere lithography combined with metal-assisted chemical etching and anisotropic chemical etching

    NASA Astrophysics Data System (ADS)

    Asoh, Hidetaka; Fujihara, Kosuke; Ono, Sachiko

    2012-07-01

    The morphological change of silicon macropore arrays formed by metal-assisted chemical etching using shape-controlled Au thin film arrays was investigated during anisotropic chemical etching in tetramethylammonium hydroxide (TMAH) aqueous solution. After the deposition of Au as the etching catalyst on (111) silicon through a honeycomb mask prepared by sphere lithography, the specimens were etched in a mixed solution of HF and H2O2 at room temperature, resulting in the formation of ordered macropores in silicon along the [111] direction, which is not achievable by conventional chemical etching without a catalyst. In the anisotropic etching in TMAH, the macropores changed from being circular to being hexagonal and finally to being triangular, owing to the difference in etching rate between the crystal planes.

  16. Dandy-Walker syndrome and chromosomal abnormalities.

    PubMed

    Imataka, George; Yamanouchi, Hideo; Arisaka, Osamu

    2007-12-01

    Dandy-Walker syndrome (DWS) is a brain malformation of unknown etiology, but several reports have been published indicating that there is a causal relationship to various types of chromosomal abnormalities and malformation syndromes. In the present article, we present a bibliographical survey of several previously issued reports on chromosomal abnormalities associated with DWS, including our case of DWS found in trisomy 18. There are various types of chromosomal abnormalities associated with DWS; most of them are reported in chromosome 3, 9, 13 and 18. We also summarize some other chromosomal abnormalities and various congenital malformation syndromes.

  17. Excess Secretion of Gel-Forming Mucins and Associated Innate Defense Proteins with Defective Mucin Un-Packaging Underpin Gallbladder Mucocele Formation in Dogs

    PubMed Central

    Kesimer, Mehmet; Cullen, John; Cao, Rui; Radicioni, Giorgia; Mathews, Kyle G.; Seiler, Gabriela; Gookin, Jody L.

    2015-01-01

    Mucosal protection of the gallbladder is vital yet we know very little about the mechanisms involved. In domestic dogs, an emergent syndrome referred to as gallbladder mucocele formation is characterized by excessive secretion of abnormal mucus that results in obstruction and rupture of the gallbladder. The cause of gallbladder mucocele formation is unknown. In these first mechanistic studies of this disease, we investigated normal and mucocele-forming dog gallbladders to determine the source, identity, biophysical properties, and protein associates of the culprit mucins with aim to identify causes for abnormal mucus behavior. We established that mucocele formation involves an adoptive excess secretion of gel forming mucins with abnormal properties by the gallbladder epithelium. The mucus is characterized by a disproportionally significant increase in Muc5ac relative to Muc5b, defective mucin un-packaging, and mucin-interacting innate defense proteins that are capable of dramatically altering the physical and functional properties of mucus. These findings provide an explanation for abnormal mucus behavior and based on similarity to mucus observed in the airways of people with cystic fibrosis, suggest that abnormal mechanisms for maintenance of gallbladder epithelial hydration may be an instigating factor for mucocele formation in dogs. PMID:26414376

  18. Suppression of the heterotrimeric G protein causes abnormal morphology, including dwarfism, in rice

    PubMed Central

    Fujisawa, Yukiko; Kato, Teruhisa; Ohki, Shizuka; Ishikawa, Atsushi; Kitano, Hidemi; Sasaki, Takuji; Asahi, Tadashi; Iwasaki, Yukimoto

    1999-01-01

    Transgenic rice containing an antisense cDNA for the α subunit of rice heterotrimeric G protein produced little or no mRNA for the subunit and exhibited abnormal morphology, including dwarf traits and the setting of small seeds. In normal rice, the mRNA for the α subunit was abundant in the internodes and florets, the tissues closely related to abnormality in the dwarf transformants. The position of the α-subunit gene was mapped on rice chromosome 5 by mapping with the restriction fragment length polymorphism. The position was closely linked to the locus of a rice dwarf mutant, Daikoku dwarf (d-1), which is known to exhibit abnormal phenotypes similar to those of the transformants that suppressed the endogenous mRNA for the α subunit by antisense technology. Analysis of the cDNAs for the α subunits of five alleles of Daikoku dwarf (d-1), ID-1, DK22, DKT-1, DKT-2, and CM1361–1, showed that these dwarf mutants had mutated in the coding region of the α-subunit gene. These results show that the G protein functions in the formation of normal internodes and seeds in rice. PMID:10377457

  19. Identification of a novel Lymantria dispar nucleopolyhedrovirus mutant that exhibits abnormal polyhedron formation and virion occlusion

    Treesearch

    James M. Slavicek; Melissa J. Mercer; Dana Pohlman; Mary Ellen Kelly; David S. Bischoff

    1998-01-01

    In previous studies on the formation of Lymantria dispar nuclear polyhedrosis virus (LdMNPV) few polyhedra (FP) mutants, several polyhedron formation mutants (PFM) were identified that appeared to be unique. These viral mutants are being characterized to investigate the processes of polyhedron formation and virion occlusion. Ld

  20. Abnormal regulation of adenosine 3′,5′-monophosphate and corticosterone formation in an adrenocortical carcinoma

    PubMed Central

    Ney, R. L.; Hochella, N. J.; Grahame-Smith, D. G.; Dexter, R. N.; Butcher, R. W.

    1969-01-01

    A spontaneously occurring rat adrenocortical carcinoma which produces corticosterone was maintained by transplantation. The carcinoma appeared to utilize corticosterone biosynthetic steps similar to those of the normal adrenal, but the tumor produced only about 1-10% as much corticosterone per unit tissue weight as nontumorous adrenal glands. The tumor demonstrated little or no increase in corticosterone production in response to adrenocorticotropic hormone (ACTH) either in vivo or in vitro. In normal adrenals, ACTH increases the activity of adenyl cyclase which catalyzes the conversion of adenosine triphosphate (ATP) to adenosine-3′,5′-monophosphate (cyclic AMP), the latter then serving as an intracellular regulator of steroidogenesis. ACTH failed to increase cyclic AMP levels in the tumor in vivo or in slices in vitro, conditions under which there were 50- and 20-fold increases in nontumorous adrenals. However, in homogenates fortified with exogenous ATP, adenyl cyclase activity was comparable in the tumor and adrenals, and cyclic AMP formation was increased 3-fold by ACTH in each. As measured in homogenates, the tumor did not possess a greater ability to destroy cyclic AMP than did normal adrenals. Although ATP levels in the carcinoma were found to be considerably lower than those in normal adrenals, it was not clear that this finding can explain the inability of ACTH to increase cyclic AMP levels in intact tumor cells. While the failure to normally influence cyclic AMP levels in the carcinoma cells could be an important factor in the lack of a steroid response to ACTH, several lines of evidence suggest that the tumor possesses one or more additional abnormalities in the regulation of steroidogenesis. First, in the absence of ACTH stimulation, the tissue concentrations of cyclic AMP were comparable in the tumor and in nontumorous adrenals, but these cyclic AMP levels were associated with a lower level of steroidogenesis in the tumor. Second, tumor slices

  1. Retrospective analysis of the incidence of epidural haematoma in patients with epidural catheters and abnormal coagulation parameters.

    PubMed

    Gulur, P; Tsui, B; Pathak, R; Koury, K M; Lee, H

    2015-05-01

    Epidural haematoma is a rare but potentially catastrophic complication associated with epidural catheterization. The times of insertion and removal of epidural catheters are high-risk periods for epidural haematoma formation, especially with abnormal coagulation parameters. There is a lack of data on the incidence of epidural haematoma in patients with abnormal coagulation parameters. A retrospective analysis was undertaken from 2002 to 2009 on patients with an epidural catheter. Queries were performed on the coagulation parameters for the dates of placement and removal of the catheters and on all documented epidural haematoma cases. During the study period, 11 600 epidural catheters were placed. In the setting of abnormal coagulation parameters, 278 (2.4%) epidural catheters were placed and 351 (3%) were removed. Two epidural haematomas occurred; both patients had epidural catheters and spinal drains placed for vascular procedures with abnormal coagulation parameters after operatation. The haematomas occurred after removal of the catheters. Based on our study, the incidence of epidural haematoma in patients with abnormal coagulation parameters is 1 in 315 patients, with the lower limit of the 95% confidence interval at 87 and the upper limit at 2597. The risk of epidural haematoma is clearly elevated with abnormal coagulation parameters. Our data suggest that as the incidence of epidural haematoma with neuraxial access in patients with abnormal coagulation is not 100%, individual risk-benefit evaluations are warranted. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Macroporous hydrogel micropillars for quantifying Met kinase activity in cancer cell lysates.

    PubMed

    Powers, Alicia D; Liu, Bi; Lee, Andrew G; Palecek, Sean P

    2012-09-07

    Overactive and overexpressed kinases have been implicated in the cause and progression of many cancers. Kinase inhibitors offer a targeted approach for treating cancers associated with increased or deregulated kinase activity. Often, however, cancer cells exhibit initial resistance to these inhibitors or evolve to develop resistance during treatment. Additionally, cancers of any one tissue type are typically heterogeneous in their oncogenesis mechanisms, and thus diagnosis of a particular type of cancer does not necessarily provide insight into what kinase therapies may be effective. For example, while some lung cancer cells that overexpress the epidermal growth factor receptor (EFGR) respond to treatment with EGFR kinase inhibitors, overexpression or hyperactivity of Met kinase correlates with resistance to EGFR kinase inhibitors. Here we describe a microfluidic-based assay for quantifying Met kinase activity in cancer cell lysates with the eventual goals of predicting cancer cell responsiveness to kinase inhibitors and monitoring development of resistance to these inhibitors. In this assay, we immobilized a phosphorylation substrate for Met kinase into macroporous hydrogel micropillars. We then exposed the micropillars to a cancer cell lysate and detected substrate phosphorylation using a fluorescently conjugated antibody. This assay is able to quantify Met kinase activity in whole cell lysate from as few as 150 cancer cells. It can also detect cells expressing overactive Met kinase in a background of up to 75% non-cancerous cells. Additionally, the assay can quantify kinase inhibition by the Met-specific kinase inhibitors SU11274 and PHA665752, suggesting predictive capability for cellular response to kinase inhibitors.

  3. Root induced changes of effective 1D hydraulic properties in a soil column.

    PubMed

    Scholl, P; Leitner, D; Kammerer, G; Loiskandl, W; Kaul, H-P; Bodner, G

    Roots are essential drivers of soil structure and pore formation. This study aimed at quantifying root induced changes of the pore size distribution (PSD). The focus was on the extent of clogging vs. formation of pores during active root growth. Parameters of Kosugi's lognormal PSD model were determined by inverse estimation in a column experiment with two cover crops (mustard, rye) and an unplanted control. Pore dynamics were described using a convection-dispersion like pore evolution model. Rooted treatments showed a wider range of pore radii with increasing volumes of large macropores >500 μm and micropores <2.5 μm, while fine macropores, mesopores and larger micropores decreased. The non-rooted control showed narrowing of the PSD and reduced porosity over all radius classes. The pore evolution model accurately described root induced changes, while structure degradation in the non-rooted control was not captured properly. Our study demonstrated significant short term root effects with heterogenization of the pore system as dominant process of root induced structure formation. Pore clogging is suggested as a partial cause for reduced pore volume. The important change in micro- and large macropores however indicates that multiple mechanic and biochemical processes are involved in root-pore interactions.

  4. Biodiesel production from transesterification of palm oil with methanol over CaO supported on bimodal meso-macroporous silica catalyst.

    PubMed

    Witoon, Thongthai; Bumrungsalee, Sittisut; Vathavanichkul, Peerawut; Palitsakun, Supaphorn; Saisriyoot, Maythee; Faungnawakij, Kajornsak

    2014-03-01

    Calcium oxide-loaded porous materials have shown promise as catalysts in transesterification. However, the slow diffusion of bulky triglycerides through the pores limited the activity of calcium oxide (CaO). In this work, bimodal meso-macroporous silica was used as a support to enhance the accessibility of the CaO dispersed inside the pores. Unimodal porous silica having the identical mesopore diameter was employed for the purpose of comparison. Effects of CaO content and catalyst pellet size on the yield of fatty acid methyl esters (FAME) were investigated. The basic strength was found to increase with increasing the CaO content. The CaO-loaded bimodal porous silica catalyst with the pellet size of 325μm achieved a high %FAME of 94.15 in the first cycle, and retained an excellent %FAME of 88.87 after five consecutive cycles. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Enhanced photocatalytic degradation of 2-propanol over macroporous GaN/ZnO solid solution prepared by a novel sol-gel method

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

    Wang, Lizhong; Ouyang, Shuxin; Ren, Bofan

    2015-10-01

    Macroporous GaN/ZnO solid solution photocatalyst is synthesized through a novel sol-gel method under mild conditions. The performance of as-synthesized solid solution photocatalyst is evaluated for decomposition of gaseous 2-propanol (IPA). It is found that due to enhancement in both the adsorption to gaseous IPA and the absorbance to visible light, the porous GaN/ZnO solid solution exhibits a good photocatalytic performance for IPA decomposition. Moreover, the mechanism for photocatalytic degradation IPA over porous GaN/ZnO solid solution is also investigated in comparison with those for the two end materials ZnO and GaN. The trapping effects with different scavengers prove that both themore » photoexcited electrons and holes affect the IPA photodegradation process, simultaneously.« less

  6. Preliminary enrichment and separation of genistein and apigenin from extracts of pigeon pea roots by macroporous resins.

    PubMed

    Liu, Wei; Zhang, Su; Zu, Yuan-Gang; Fu, Yu-Jie; Ma, Wei; Zhang, Dong-Yang; Kong, Yu; Li, Xiao-Juan

    2010-06-01

    Enrichment and separation of genistein and apigenin from extracts of pigeon pea roots were studied using eleven macroporous resins with different physical and chemical properties. ADS-5 resin showed the maximum effectiveness among the tested resins. The solute affinity towards ADS-5 resin at different temperatures was described in terms of Langmuir and Freundlich isotherms, and the equilibrium experimental data were well-fitted to the two isotherms. In order to optimize the operating parameters for separating genistein and apigenin, dynamic adsorption and desorption tests were carried out. After one run treatment with ADS-5 resin, the contents of genistein and apigenin in the product were 9.36-fold and 11.09-fold increased with recovery yields of 89.78% and 93.41%, respectively. The process achieved easy and effective enrichment and separation of genistein and apigenin by using ADS-5 resin, and it is a promising basis for large-scale preparation of genistein and apigenin from pigeon pea or other plants extracts. (c) 2010 Elsevier Ltd. All rights reserved.

  7. A critical review on gas diffusion micro and macroporous layers degradations for improved membrane fuel cell durability

    NASA Astrophysics Data System (ADS)

    Lapicque, Francois; Belhadj, Mariem; Bonnet, Caroline; Pauchet, Joël; Thomas, Yohann

    2016-12-01

    Formerly considered as a secondary component of fuel cell, gas diffusion layers (GDLs) have been shown to have a key role in gas transport to the catalyst layers and in water management: in particular, the microporous layer (MPL) deposited on the diffusion substrate has an active part in water distribution in the membrane electrode assembly and in its efficient removal from the cell. In addition to its perfect design for the targeted application and in combination with the macroporous substrate (MPS), the MPL structure and physicochemical properties have to contribute to the cell durability, which is still considered as insufficient for larger, massive commercialisation of this energy conversion system. The paper is aimed at reviewing the main knowledge gained on the role of the MPL on GDL operation and durability, with investigation of degradation phenomena of both MPL and MPS, together with the role played by the MPL in mitigating the occurrence of degradation phenomena that can occur in the whole fuel cell. In addition to the reviewing purpose, original data on ex-situ degradation of GDL are presented.

  8. Macroporous Silica with Thick Framework for Steam-Stable and High-Performance Poly(ethyleneimine)/Silica CO2 Adsorbent.

    PubMed

    Min, Kyungmin; Choi, Woosung; Choi, Minkee

    2017-06-09

    Poly(ethyleneimine) (PEI)/silica has been widely studied as a solid adsorbent for post-combustion CO 2 capture. In this work, a highly macroporous silica (MacS), synthesized by secondary sintering of fumed silica, is compared with various mesoporous silicas with different pore structures as a support for PEI. The silicas with large pore diameter and volume enabled high CO 2 adsorption kinetics and capacity, because pore occlusion by the supported PEI was minimized. The steam stability of the silica structures increased with the silica wall thickness owing to suppressed framework ripening. The silicas with low steam stability showed rapid leaching of PEI, which indicated that the PEI squeezed out of the collapsed silica pores leached more readily. Consequently, MacS that had an extra-large pore volume (1.80 cm 3  g -1 ) and pore diameter (56.0 nm), and a thick wall (>10 nm), showed the most promising CO 2 adsorption kinetics and capacity as well as steam stability. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Structural and behavioral correlates of abnormal encoding of money value in the sensorimotor striatum in cocaine addiction

    PubMed Central

    Konova, Anna B.; Moeller, Scott J.; Tomasi, Dardo; Parvaz, Muhammad A.; Alia-Klein, Nelly; Volkow, Nora D.; Goldstein, Rita Z.

    2012-01-01

    Abnormalities in frontostriatal systems are thought to be central to the pathophysiology of addiction, and may underlie maladaptive processing of the highly generalizable reinforcer, money. Although abnormal frontostriatal structure and function have been observed in individuals addicted to cocaine, it is less clear how individual variability in brain structure is associated with brain function to influence behavior. Our objective was to examine frontostriatal structure and neural processing of money value in chronic cocaine users and closely matched healthy controls. A reward task that manipulated different levels of money was used to isolate neural activity associated with money value. Gray matter volume measures were used to assess frontostriatal structure. Our results indicated that cocaine users had an abnormal money value signal in the sensorimotor striatum (right putamen/globus pallidus) which was negatively associated with accuracy adjustments to money and was more pronounced in individuals with more severe use. In parallel, group differences were also observed in both function and gray matter volume of the ventromedial prefrontal cortex; in the cocaine users, the former was directly associated with response to money in the striatum. These results provide strong evidence for abnormalities in the neural mechanisms of valuation in addiction and link these functional abnormalities with deficits in brain structure. In addition, as value signals represent acquired associations, their abnormal processing in the sensorimotor striatum, a region centrally implicated in habit formation, could signal disadvantageous associative learning in cocaine addiction. PMID:22775285

  10. Pinna abnormalities and low-set ears

    MedlinePlus

    ... Pinna abnormalities; Genetic defect - pinna; Congenital defect - pinna Images Ear abnormalities Pinna of the newborn ear References Haddad J, Keesecker S. Congenital malformations. In: Kliegman RM, Stanton BF, ...

  11. Abnormalities associated with congenital scoliosis: a retrospective study of 226 Chinese surgical cases.

    PubMed

    Shen, Jianxiong; Wang, Zijia; Liu, Jiaming; Xue, Xuhong; Qiu, Guixing

    2013-05-01

    Retrospective study of a series of 226 consecutive Chinese patients with congenital scoliosis. To identify the incidence of intraspinal abnormalities and other organ defects in surgical patients with congenital scoliosis in Chinese population. Previous studies have revealed high rates of intraspinal anomalies and other organ defects in patients with congenital scoliosis. The incidence of abnormalities in patients with congenital scoliosis in Chinese population has not been reported. A total of 226 patients with congenital scoliosis underwent surgical treatment in Peking Union Medical College Hospital between January 2005 and March 2011 were identified. A definitive diagnosis of congenital scoliosis for all patients was made. Complete data were reviewed, including medical records, plain radiograph, magnetic resonance (MR) image of the whole spine, echocardiography, and renal ultrasound. The incidence of intraspinal abnormalities and other organ defects were analyzed. Intraspinal abnormalities were found in 99 (43%) patients. Diastematomyelia was identified to be the most common intraspinal pathological anomaly, which was different from the previous reports. The incidence of intraspinal anomaly in patients with failures of segmentation and mixed defects were significantly higher than those with failures of formation. Patients with thoracic hemivertebrae were found to have a higher incidence of intraspinal abnormalities than patients with lumbar hemivertebrae. Patients with intraspinal abnormality had a higher incidence of positive clinical findings than those with normal magnetic resonance imaging. However, the difference between the 2 groups was not statistically significant. Other organic defects were found in 91(40%) patients. Cardiac defects were detected in 18%, urogenital anomalies in 12%, and gastrointestinal anomalies in 5% of the patients in this study. Diastematomyelia was found to be the most common intraspinal pathological anomaly and cardiac defects were

  12. Preparative separation and purification of rebaudioside a from steviol glycosides using mixed-mode macroporous adsorption resins.

    PubMed

    Liu, Yongfeng; Di, Duolong; Bai, Qingqing; Li, Jintian; Chen, Zhenbin; Lou, Song; Ye, Helin

    2011-09-14

    Preparative separation and purification of rebaudioside A from steviol glycosides using mixed-mode macroporous adsorption resins (MARs) were systematically investigated. Mixed-mode MARs were prepared by a physical blending method. By evaluation of the adsorption/desorption ratio and adsorption/desorption capacity of mixed-mode MARs with different proportions toward RA and ST, the mixed-mode MAR 18 was chosen as the optimum strategy. On the basis of the static tests, it was found that the experimental data fitted best to the pseudosecond-order kinetics and Temkin-Pyzhev isotherm. Furthermore, the dynamic adsorption/desorption experiments were performed on the mini column packed with mixed-mode MAR 18. After one run treatment, the purity of rebaudioside A in purified product increased from 40.77 to 60.53%, with a yield rate of 38.73% (W/W), and that in residual product decreased from 40.77 to 36.17%, with a recovery yield of 57.61% (W/W). The total recovery yield reached 96.34% (W/W). The results showed that this method could be utilized in large-scale production of rebaudioside A from steviol glycosides in industry.

  13. Crumbs 2 prevents cortical abnormalities in mouse dorsal telencephalon.

    PubMed

    Dudok, Jacobus J; Murtaza, Mariyam; Henrique Alves, C; Rashbass, Pen; Wijnholds, Jan

    2016-07-01

    The formation of a functionally integrated nervous system is dependent on a highly organized sequence of events that includes timely division and differentiation of progenitors. Several apical polarity proteins have been shown to play crucial roles during neurogenesis, however, the role of Crumbs 2 (CRB2) in cortical development has not previously been reported. Here, we show that conditional ablation of Crb2 in the murine dorsal telencephalon leads to defects in the maintenance of the apical complex. Furthermore, within the mutant dorsal telencephalon there is premature expression of differentiation proteins. We examined the physiological function of Crb2 on wild type genetic background as well as on background lacking Crb1. Telencephalon lacking CRB2 resulted in reduced levels of PALS1 and CRB3 from the apical complex, an increased number of mitotic cells and expanded neuronal domain. These defects are transient and therefore only result in rather mild cortical abnormalities. We show that CRB2 is required for maintenance of the apical polarity complex during development of the cortex and regulation of cell division, and that loss of CRB2 results in cortical abnormalities. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  14. Diabetes synergistically exacerbates poststroke dementia and tau abnormality in brain.

    PubMed

    Zhang, Ting; Pan, Bai-Shen; Sun, Guang-Chun; Sun, Xiao; Sun, Feng-Yan

    2010-07-01

    This study investigated whether exacerbation of poststroke dementia by diabetes associated abnormal tau phosphorylation and its mechanism. Streptozotocin (STZ) injection and/or a high fat diet (HFD) were used to treat rats to induce type 1 and 2 diabetes. Animals were randomly divided into STZ, HFD, STZ-HFD, and normal diet (NPD) groups. Focal ischemic stroke was induced by middle cerebral artery occlusion (MCAO). Cognitive function was tested by the Morris water maze. STZ or STZ-HFD treatment exacerbated ischemia-induced cognitive deficits, brain infarction and reduction of synaptophysin expression. Moreover, we found that diabetes further increased AT8, a marker of hyperphosphorylated tau, protein and immunopositive stained cells in the hippocampus of rats following MCAO while reduced the level of phosphorylated glycogen synthase kinase 3-beta at serine-9 residues (p-ser9-GSK-3beta), indicating activation of GSK-3beta. We conclude that diabetes further deteriorates ischemia-induced brain damage and cognitive deficits which may be associated with abnormal phosphorylation of tau as well as activation of GSK-3beta. These findings may be helpful for developing new strategies to prevent/delay formation of poststroke dementia in patients with diabetes. 2010 Elsevier Ltd. All rights reserved.

  15. Self-expandable macroporous nitinol stents for transfemoral exclusion of aortic aneurysms in dogs: preliminary results.

    PubMed

    Hagen, B; Harnoss, B M; Trabhardt, S; Ladeburg, M; Fuhrmann, H; Franck, C

    1993-01-01

    This experimental study evaluated the feasibility of excluding artificially created aortic aneurysms in dogs with transfemorally inserted nitinol stents, serving as intraluminal bypass. Infrarenal aortic aneurysms were created in eleven dogs (28-35 kg) by end-to-end anastomosis of sacciform conduits. Single and double wire-knitted, macroporous, superelastic, self-expanding nitinol stents without any additional wrapping or in-between fabrics served as endovascular grafts. The pore size of the double-knitted stents was less than 0.7 mm2. Angiography following stent placement showed immediate exclusion of the aneurysms for the double-knitted stents. For the single-knitted stents (2 cases), partial exclusion was achieved only after considerable delay. CT studies in the dogs with the double-knitted stents revealed patency of the grafts after 3 to 5 weeks with the aneurysms totally thrombosed. So far gross pathology of 1 dog at 24 h and 1 at 12 months revealed patency of the stents. At 12 months histopathology showed a neointima covering the inner stent surface with the aneurysm filled by an organized thrombus. It is concluded, that an "open" stent with a tight meshwork appears to be a suitable device to instantly exclude artificial aneurysms of the canine aorta.

  16. Dysmorphometrics: the modelling of morphological abnormalities.

    PubMed

    Claes, Peter; Daniels, Katleen; Walters, Mark; Clement, John; Vandermeulen, Dirk; Suetens, Paul

    2012-02-06

    The study of typical morphological variations using quantitative, morphometric descriptors has always interested biologists in general. However, unusual examples of form, such as abnormalities are often encountered in biomedical sciences. Despite the long history of morphometrics, the means to identify and quantify such unusual form differences remains limited. A theoretical concept, called dysmorphometrics, is introduced augmenting current geometric morphometrics with a focus on identifying and modelling form abnormalities. Dysmorphometrics applies the paradigm of detecting form differences as outliers compared to an appropriate norm. To achieve this, the likelihood formulation of landmark superimpositions is extended with outlier processes explicitly introducing a latent variable coding for abnormalities. A tractable solution to this augmented superimposition problem is obtained using Expectation-Maximization. The topography of detected abnormalities is encoded in a dysmorphogram. We demonstrate the use of dysmorphometrics to measure abrupt changes in time, asymmetry and discordancy in a set of human faces presenting with facial abnormalities. The results clearly illustrate the unique power to reveal unusual form differences given only normative data with clear applications in both biomedical practice & research.

  17. Congenital Abnormalities

    MedlinePlus

    ... tube defects. However, there is also a genetic influence to this type of congenital anomaly. Unknown Causes The vast majority of congenital abnormalities have no known cause. This is particularly troubling for parents who plan to have more children, because there is no way to predict if ...

  18. Frequency of metabolic abnormalities in urinary stones patients.

    PubMed

    Ahmad, Iftikhar; Pansota, Mudassar Saeed; Tariq, Muhammad; Tabassum, Shafqat Ali

    2013-11-01

    To determine the frequency of metabolic abnormalities in the serum and urine of patients with urinary stones disease. Two hundred patients with either multiple or recurrent urolithiasis diagnosed on ultrasonography and intravenous urography were included in this study. 24 hour urine sample were collected from each patient and sent for PH, specific gravity, Creatinine, uric acid, calcium, phosphate, oxalate, citrate and magnesium. In addition, blood sample of each patient was also sent for serum levels of urea, creatinine, uric acid, phosphate and calcium. Mean age of patients was 38 ± 7.75 years with male to female ratio of 2:1. The main presenting complaint was lumber pain and 82.5% patients were found to have calcium oxalate stones on chemical analysis. Metabolic abnormalities were found in 90.5% patients, whereas there were no metabolic abnormalities in 19 (9.5%) patients. Forty patients (21.5%) only had one metabolic abnormality and 157 (78.5%) patients had multiple metabolic abnormalities. Hyperoxaluria was the most commonly observed metabolic abnormality and was found in 64.5% patients. Other significant metabolic abnormalities were hypercalciuria, Hypercalcemia, hypocitraturia and hyperuricemia. This study concludes that frequency of metabolic abnormalities is very high in patients with urolithiasis and hyperoxaluria, hypercalciuria and hypocitraturia are the most important metabolic abnormalities observed in these patients.

  19. Abnormal Cervical Cancer Screening Test Results

    MedlinePlus

    ... FAQ187 GYNECOLOGIC PROBLEMS Abnormal Cervical Cancer Screening Test Results • What is cervical cancer screening? • What causes abnormal cervical cancer screening test results? • What is the difference between the terms cervical ...

  20. Tooth - abnormal shape

    MedlinePlus

    Hutchinson incisors; Abnormal tooth shape; Peg teeth; Mulberry teeth; Conical teeth ... The appearance of normal teeth varies, especially the molars. ... conditions. Specific diseases can affect tooth shape, tooth ...

  1. Developing software to "track and catch" missed follow-up of abnormal test results in a complex sociotechnical environment.

    PubMed

    Smith, M; Murphy, D; Laxmisan, A; Sittig, D; Reis, B; Esquivel, A; Singh, H

    2013-01-01

    Abnormal test results do not always receive timely follow-up, even when providers are notified through electronic health record (EHR)-based alerts. High workload, alert fatigue, and other demands on attention disrupt a provider's prospective memory for tasks required to initiate follow-up. Thus, EHR-based tracking and reminding functionalities are needed to improve follow-up. The purpose of this study was to develop a decision-support software prototype enabling individual and system-wide tracking of abnormal test result alerts lacking follow-up, and to conduct formative evaluations, including usability testing. We developed a working prototype software system, the Alert Watch And Response Engine (AWARE), to detect abnormal test result alerts lacking documented follow-up, and to present context-specific reminders to providers. Development and testing took place within the VA's EHR and focused on four cancer-related abnormal test results. Design concepts emphasized mitigating the effects of high workload and alert fatigue while being minimally intrusive. We conducted a multifaceted formative evaluation of the software, addressing fit within the larger socio-technical system. Evaluations included usability testing with the prototype and interview questions about organizational and workflow factors. Participants included 23 physicians, 9 clinical information technology specialists, and 8 quality/safety managers. Evaluation results indicated that our software prototype fit within the technical environment and clinical workflow, and physicians were able to use it successfully. Quality/safety managers reported that the tool would be useful in future quality assurance activities to detect patients who lack documented follow-up. Additionally, we successfully installed the software on the local facility's "test" EHR system, thus demonstrating technical compatibility. To address the factors involved in missed test results, we developed a software prototype to account for

  2. What proportion of congenital abnormalities can be prevented?

    PubMed Central

    Czeizel, A E; Intôdy, Z; Modell, B

    1993-01-01

    OBJECTIVE--To estimate the proportion of preventable congenital abnormalities in Hungary. DESIGN--Analysis of available Hungarian data-bases and of the effectiveness of primary, secondary, and tertiary preventive methods. SETTING--Databases of ad hoc epidemiological studies and of the Hungarian congenital abnormality registry. MAIN OUTCOME MEASURES--Prevalence at birth and prevalence after prevention in 73 congenital abnormality types or groups. RESULTS--Preventive methods are available for 51 (70%) of the 73 congenital abnormality types or groups evaluated. The birth prevalence of all congenital abnormalities could be reduced from 65 to 26 per 1000; thus 39 per 1000 (60%) are preventable. Without congenital dislocation of the hip, which is unusually common in Hungary, the preventable proportion of congenital abnormalities is 52%. CONCLUSION--Many congenital abnormalities can be prevented, but as they do not represent a single pathological category there is no single strategy for their prevention. Images p502-a p503-a PMID:8448464

  3. Structural and behavioral correlates of abnormal encoding of money value in the sensorimotor striatum in cocaine addiction.

    PubMed

    Konova, Anna B; Moeller, Scott J; Tomasi, Dardo; Parvaz, Muhammad A; Alia-Klein, Nelly; Volkow, Nora D; Goldstein, Rita Z

    2012-10-01

    Abnormalities in frontostriatal systems are thought to be central to the pathophysiology of addiction, and may underlie the maladaptive processing of the highly generalizable reinforcer, money. Although abnormal frontostriatal structure and function have been observed in individuals addicted to cocaine, it is less clear how individual variability in brain structure is associated with brain function to influence behavior. Our objective was to examine frontostriatal structure and neural processing of money value in chronic cocaine users and closely matched healthy controls. A reward task that manipulated different levels of money was used to isolate neural activity associated with money value. Gray matter volume measures were used to assess frontostriatal structure. Our results indicated that cocaine users had an abnormal money value signal in the sensorimotor striatum (right putamen/globus pallidus) that was negatively associated with accuracy adjustments to money and was more pronounced in individuals with more severe use. In parallel, group differences were also observed in both the function and gray matter volume of the ventromedial prefrontal cortex; in the cocaine users, the former was directly associated with response to money in the striatum. These results provide strong evidence for abnormalities in the neural mechanisms of valuation in addiction and link these functional abnormalities with deficits in brain structure. In addition, as value signals represent acquired associations, their abnormal processing in the sensorimotor striatum, a region centrally implicated in habit formation, could signal disadvantageous associative learning in cocaine addiction. © 2012 Published 2012. This article is a US Government work and is in the public domain in the USA.

  4. Neural conduction abnormality in the brain stem and prevalence of the abnormality in late preterm infants with perinatal problems.

    PubMed

    Jiang, Ze Dong

    2013-08-01

    Neurodevelopment in late preterm infants has recently attracted considerable interest. The prevalence of brain stem conduction abnormality remains unknown. We examined maximum length sequence brain stem auditory evoked response in 163 infants, born at 33-36 weeks gestation, who had various perinatal problems. Compared with 49 normal term infants without problems, the late preterm infants showed a significant increase in III-V and I-V interpeak intervals at all 91-910/s clicks, particularly at 455 and 910/s (p < 0.01-0.001). The I-III interval was slightly increased, without statistically significant difference from the controls at any click rates. These results suggest that neural conduction along the, mainly more central or rostral part of, auditory brain stem is abnormal in late preterm infants with perinatal problems. Of the 163 late preterm infant, the number (and percentage rate) of infants with abnormal I-V interval at 91, 227, 455, and 910/s clicks was, respectively, 11 (6.5%), 17 (10.2%), 37 (22.3%), and 31 (18.7%). The number (and percentage rate) of infants with abnormal III-V interval at these rates was, respectively, 10 (6.0%), 17 (10.2%), 28 (16.9), and 36 (21.2%). Apparently, the abnormal rates were much higher at 455 and 910/s clicks than at lower rates 91 and 227/s. In total, 42 (25.8%) infants showed abnormal I-V and/or III-V intervals. Conduction in, mainly in the more central part, the brain stem is abnormal in late preterm infants with perinatal problems. The abnormality is more detectable at high- than at low-rate sensory stimulation. A quarter of late preterm infants with perinatal problems have brain stem conduction abnormality.

  5. Frequency of metabolic abnormalities in urinary stones patients

    PubMed Central

    Ahmad, Iftikhar; Pansota, Mudassar Saeed; Tariq, Muhammad; Tabassum, Shafqat Ali

    2013-01-01

    Objective: To determine the frequency of metabolic abnormalities in the serum and urine of patients with urinary stones disease. Methods: Two hundred patients with either multiple or recurrent urolithiasis diagnosed on ultrasonography and intravenous urography were included in this study. 24 hour urine sample were collected from each patient and sent for PH, specific gravity, Creatinine, uric acid, calcium, phosphate, oxalate, citrate and magnesium. In addition, blood sample of each patient was also sent for serum levels of urea, creatinine, uric acid, phosphate and calcium. Results: Mean age of patients was 38 ± 7.75 years with male to female ratio of 2:1. The main presenting complaint was lumber pain and 82.5% patients were found to have calcium oxalate stones on chemical analysis. Metabolic abnormalities were found in 90.5% patients, whereas there were no metabolic abnormalities in 19 (9.5%) patients. Forty patients (21.5%) only had one metabolic abnormality and 157 (78.5%) patients had multiple metabolic abnormalities. Hyperoxaluria was the most commonly observed metabolic abnormality and was found in 64.5% patients. Other significant metabolic abnormalities were hypercalciuria, Hypercalcemia, hypocitraturia and hyperuricemia. Conclusion: This study concludes that frequency of metabolic abnormalities is very high in patients with urolithiasis and hyperoxaluria, hypercalciuria and hypocitraturia are the most important metabolic abnormalities observed in these patients. PMID:24550954

  6. Natural history of echocardiographic abnormalities in mucopolysaccharidosis III.

    PubMed

    Wilhelm, Carolyn M; Truxal, Kristen V; McBride, Kim L; Kovalchin, John P; Flanigan, Kevin M

    2018-06-01

    Mucopolysaccharidosis (MPS) type III, Sanfilippo Syndrome, is an autosomal recessive lysosomal storage disorder. MPS I and II patients often develop cardiac involvement leading to early mortality, however there are limited data in MPS III. The objective of this study is to describe cardiac abnormalities in a large group of MPS III patients followed in a longitudinal natural history study designed to determine outcome measures for gene transfer trials. A single center study of MPS III patients who were enrolled in the Nationwide Children's Hospital natural history study in 2014. Two cardiologists reviewed all patient echocardiograms for anatomic, valvular, and functional abnormalities. Valve abnormalities were defined as abnormal morphology, trivial mitral regurgitation (MR) with abnormal morphology or at least mild MR, and any aortic regurgitation (AR). Abnormal left ventricular (LV) function was defined as ejection fraction < 50%. Group comparisons were assessed using two-sample t-tests or Wilcoxon rank sum tests for continuous variables and chi-square or Fisher's exact tests for categorical variables. Twenty-five patients, 15 Type A and 10 Type B MPS III, underwent 45 echocardiograms. Fifteen patients (60%) demonstrated an abnormal echocardiographic finding with age at first abnormal echocardiogram within the study being 6.8 ± 2.8 years. Left-sided valve abnormalities were common over time: 7 mitral valve thickening, 2 mitral valve prolapse, 16 MR (8 mild, 8 trivial), 3 aortic valve thickening, and 9 AR (7 mild, 2 trivial). Two patients had asymmetric LV septal hypertrophy. No valvular stenosis or ventricular function abnormalities were noted. Incidental findings included: mild aortic root dilation (2), bicommissural aortic valve (1), and mild tricuspid regurgitation (3). Individuals with Sanfilippo A and B demonstrate a natural history of cardiac involvement with valvular abnormalities most common. In short-term follow up, patients demonstrated only

  7. Ergonomics for enhancing detection of machine abnormalities.

    PubMed

    Illankoon, Prasanna; Abeysekera, John; Singh, Sarbjeet

    2016-10-17

    Detecting abnormal machine conditions is of great importance in an autonomous maintenance environment. Ergonomic aspects can be invaluable when detection of machine abnormalities using human senses is examined. This research outlines the ergonomic issues involved in detecting machine abnormalities and suggests how ergonomics would improve such detections. Cognitive Task Analysis was performed in a plant in Sri Lanka where Total Productive Maintenance is being implemented to identify sensory types that would be used to detect machine abnormalities and relevant Ergonomic characteristics. As the outcome of this research, a methodology comprising of an Ergonomic Gap Analysis Matrix for machine abnormality detection is presented.

  8. Sex chromosome abnormalities and psychiatric diseases

    PubMed Central

    Zhang, Xinzhu; Yang, Jian; Li, Yuhong; Ma, Xin; Li, Rena

    2017-01-01

    Excesses of sex chromosome abnormalities in patients with psychiatric diseases have recently been observed. It remains unclear whether sex chromosome abnormalities are related to sex differences in some psychiatric diseases. While studies showed evidence of susceptibility loci over many sex chromosomal regions related to various mental diseases, others demonstrated that the sex chromosome aneuploidies may be the key to exploring the pathogenesis of psychiatric disease. In this review, we will outline the current evidence on the interaction of sex chromosome abnormalities with schizophrenia, autism, ADHD and mood disorders. PMID:27992373

  9. Transient abnormal Q waves during exercise electrocardiography

    PubMed Central

    Alameddine, F F; Zafari, A M

    2004-01-01

    Myocardial ischaemia during exercise electrocardiography is usually manifested by ST segment depression or elevation. Transient abnormal Q waves are rare, as Q waves indicate an old myocardial infarction. The case of a patient with exercise induced transient abnormal Q waves is reported. The potential mechanisms involved in the development of such an abnormality and its clinical implications are discussed. PMID:14676264

  10. Patterns of pulmonary maturation in normal and abnormal pregnancy.

    PubMed

    Goldkrand, J W; Slattery, D S

    1979-03-01

    Fetal pulmonary maturation may be a variable event depending on various feto-maternal environmental and biochemical influences. The patterns of maturation were studied in 211 amniotic fluid samples from 123 patients (normal 55; diabetes 23; Rh sensitization 19; preeclampsia 26). The phenomenon of globule formation from the amniotic fluid lipid extract and is relation to pulmonary maturity was utilized for this analysis. Validation of this technique is presented. A normal curve was constructed from 22 to 42 weeks; gestation and compared to the abnormal pregnancies. Patients with class A, B, and C diabetes and Rh-sensitized pregnancies had delayed pulmonary maturation. Patients with class D diabetes and preclampsia paralleled the normal course of maturation. A discussion of these results and their possible cause is presented.

  11. [Hysteroscopic polypectomy, treatment of abnormal uterine bleeding].

    PubMed

    de Los Rios, P José F; López, R Claudia; Cifuentes, P Carolina; Angulo, C Mónica; Palacios-Barahona, Arlex U

    2015-07-01

    To evaluate the effectiveness of the hysteroscopic polypectomy in terms of the decrease of the abnormal uterine bleeding. A cross-sectional and analytical study was done with patients to whom a hysteroscopic polypectomy was done for treating the abnormal uterine bleeding, between January 2009 and December 2013. The response to the treatment was evaluated via a survey given to the patients about the behavior of the abnormal uterine bleeding after the procedure and about overall satisfaction. The results were obtained after a hysteroscopic polypectomy done to 128 patients and were as follows. The average time from the polypectomy applied until the survey was 30.5 months, with a standard deviation of 18 months. 67.2% of the patients reported decreased abnormal uterine bleeding and the 32.8% reported a persistence of symptoms. On average 82.8% of the. patients were satisfied with the treatment. Bivariate and multivariate analysis showed no association between the variables studied and no improvement of abnormal uterine bleeding after surgery (polypectomy). There were no complications. Hysteroscopic polypectomy is a safe surgical treatment, which decreases on two of three patients the abnormal uterine bleeding in the presence of endometrial polyps, with an acceptable level of satisfaction.

  12. Mutations in α-Tubulin Cause Abnormal Neuronal Migration in Mice and Lissencephaly in Humans

    PubMed Central

    Keays, David A.; Tian, Guoling; Poirier, Karine; Huang, Guo-Jen; Siebold, Christian; Cleak, James; Oliver, Peter L.; Fray, Martin; Harvey, Robert J.; Molnár, Zoltán; Piñon, Maria C.; Dear, Neil; Valdar, William; Brown, Steve D.M.; Davies, Kay E.; Rawlins, J. Nicholas P.; Cowan, Nicholas J.; Nolan, Patrick; Chelly, Jamel; Flint, Jonathan

    2007-01-01

    Summary The development of the mammalian brain is dependent on extensive neuronal migration. Mutations in mice and humans that affect neuronal migration result in abnormal lamination of brain structures with associated behavioral deficits. Here, we report the identification of a hyperactive N-ethyl-N-nitrosourea (ENU)-induced mouse mutant with abnormalities in the laminar architecture of the hippocampus and cortex, accompanied by impaired neuronal migration. We show that the causative mutation lies in the guanosine triphosphate (GTP) binding pocket of α-1 tubulin (Tuba1) and affects tubulin heterodimer formation. Phenotypic similarity with existing mouse models of lissencephaly led us to screen a cohort of patients with developmental brain anomalies. We identified two patients with de novo mutations in TUBA3, the human homolog of Tuba1. This study demonstrates the utility of ENU mutagenesis in the mouse as a means to discover the basis of human neurodevelopmental disorders. PMID:17218254

  13. [INDIVIDUAL EVALUATION OF LORETA ABNORMALITIES IN IDIOPATHIC GENERALIZED EPILEPSY].

    PubMed

    Clemens, Béla; Puskás, Szilvia; Besenyei, Mónika; Kondákor, István; Hollódy, Katalin; Fogarasi, Andrós; Bense, Katalin; Emri, Miklós; Opposits Gábor; Kovács, Noémi Zsuzsanna; Fekete, István

    2016-03-30

    Contemporary neuroimaging methods disclosed structural and functional cerebral abnormalities in idiopathic generalized epilepsies (IGEs). However, individual electrical (EEG) abnormalities have not been evaluated yet in IGE patients. IGE patients were investigated in the drug-free condition and after 3-6 month of antiepileptic treatment. To estimate the reproducibility of qEEG variables a retrospective recruited cohort of IGE patients was investigated. 19-channel resting state EEG activity was recorded. For each patient a total of 2 minutes EEG activity was analyzed by LORETA (Low Resolution Electromagnetic Tomography). Raw LORETA values were Z-transformed and projected to a MRI template. Z-values outside within the [+3Z] to [-3Z] range were labelled as statistically abnormal. 1. In drug-free condition, 41-50% of IGE patients showed abnormal LORETA values. 2. Abnormal LORETA findings showed great inter-individual variability. 3. Most abnormal LORETA-findings were symmetrical. 4. Most maximum Z-values were localized to frontal or temporal cortex. 5. Succesfull treatment was mostly coupled with disappearence of LORETA-abnormality, persistent seizures were accompanied by persistent LORETA abnormality. 1. LORETA abnormalities detected in the untreated condition reflect seizure-generating property of the cortex in IGE patients. 2. Maximum LORETA-Z abnormalities were topographically congruent with structural abnormalities reported by other research groups. 3. LORETA might help to investigate drug effects at the whole-brain level.

  14. Clozapine-induced EEG abnormalities and clinical response to clozapine.

    PubMed

    Risby, E D; Epstein, C M; Jewart, R D; Nguyen, B V; Morgan, W N; Risch, S C; Thrivikraman, K V; Lewine, R L

    1995-01-01

    The authors hypothesized that patients who develop gross EEG abnormalities during clozapine treatment would have a less favorable outcome than patients who did not develop abnormal EEGs. The clinical EEGs and the Brief Psychiatric Rating Scale (BPRS) scores of 12 patients with schizophrenia and 4 patients with schizoaffective disorder were compared before and during treatment with clozapine. Eight patients developed significant EEG abnormalities on clozapine; 1 showed worsening of an abnormal pre-clozapine EEG; none of these subjects had clinical seizures. BPRS scores improved significantly in the group of patients who developed abnormal EEGs but not in the group who did not. Findings are consistent with previous reports of a high incidence of clozapine-induced EEG abnormalities and a positive association between these abnormalities and clinical improvement.

  15. Numerically abnormal chromosome constitutions in humans

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

    NONE

    1993-12-31

    Chapter 24, discusses numerically abnormal chromosome constitutions in humans. This involves abnormalities of human chromosome number, including polyploidy (when the number of sets of chromosomes increases) and aneuploidy (when the number of individual normal chromosomes changes). Chapter sections discuss the following chromosomal abnormalities: human triploids, imprinting and uniparental disomy, human tetraploids, hydatidiform moles, anomalies caused by chromosomal imbalance, 13 trisomy (D{sub 1} trisomy, Patau syndrome), 21 trisomy (Down syndrome), 18 trisomy syndrome (Edwards syndrome), other autosomal aneuploidy syndromes, and spontaneous abortions. The chapter concludes with remarks on the nonrandom participation of chromosomes in trisomy. 69 refs., 3 figs., 4 tabs.

  16. Synthesis and application of nano-, meso- and macroporous sorbents based on lignin for detoxication of biological fluids

    NASA Astrophysics Data System (ADS)

    Chopabayeva, Nazira N.; Mukanov, Kanatbek N.; Tasmagambet, Amandyk T.

    2014-05-01

    Novel nano-, meso- and macroporous sorbents based on hydrolysis lignin have been synthesized by catalytic o-alkylation of biolpolymer with epoxy resin ED-20 and subsequent amination of formed α-oxyde derivative. Composition, structure, morphology and physical, chemical properties of ion-exchangers were investigated by FTIR, SEM, TEM, porosimetry and potentiometric titration method. It has been established that alkaline activated lignin shows an increase of SBET to 20.9 m2/g while modification leads to decrease of SBET more than double (from 9.2 to 5.2 m2/g) that of an untreared sample (14.5 m2/g). Synthesized sorbents are characterized by approximately identical mesoporous structure and mainly contained a pore size of 10-14 nm. The results clearly demonstrate the efficiency of lignin based sorbents for the removal of water and lipid soluble toxic metabolites from blood serum of diabetic retinopathy patients. Samples reduced the high level of total cholesterol, including its most atherogenic fractions (LDL-C, VLDL-C), triglyceride to the level of optimum compensated diabetes without significant removal of HDL-C. Concentration of glucose was decreased to physiological norms.

  17. High-rate capability of three-dimensionally ordered macroporous T-Nb2O5 through Li+ intercalation pseudocapacitance

    NASA Astrophysics Data System (ADS)

    Lou, Shuaifeng; Cheng, Xinqun; Wang, Long; Gao, Jinlong; Li, Qin; Ma, Yulin; Gao, Yunzhi; Zuo, Pengjian; Du, Chunyu; Yin, Geping

    2017-09-01

    Orthorhombic Niobium oxide (T-Nb2O5) has been regarded as a promising anode material for high-rate lithium ion batteries (LIBs) due to its potential to operate at high rates with improved safety and high theoretical capacity of 200 mA h g-1. Herein, three-dimensionally ordered macroporous (3DOM) T-Nb2O5, with mesoporous hierarchical structure, was firstly prepared by a simple approach employing self-assembly polystyrene (PS) microspheres as hard templates. The obtained T-Nb2O5 anode material presents obvious and highly-efficiency pseudocapacitive Li+ intercalation behaviour, which plays a dominant role in the kinetics of electrode process. As a result, rapid Li+ intercalation/de-intercalation are achieved, leading to excellent rate capability and long cycle life. The 3DOM T-Nb2O5 shows a remarkable high capacity of 106 and 77 mA h g-1 at the rate of 20C and 50C. The work presented herein holds great promise for future design of material structure, and demonstrates the great potential of T-Nb2O5 as a practical high-rate anode material for LIBs.

  18. Developing Software to “Track and Catch” Missed Follow-up of Abnormal Test Results in a Complex Sociotechnical Environment

    PubMed Central

    Smith, M.; Murphy, D.; Laxmisan, A.; Sittig, D.; Reis, B.; Esquivel, A.; Singh, H.

    2013-01-01

    Summary Background Abnormal test results do not always receive timely follow-up, even when providers are notified through electronic health record (EHR)-based alerts. High workload, alert fatigue, and other demands on attention disrupt a provider’s prospective memory for tasks required to initiate follow-up. Thus, EHR-based tracking and reminding functionalities are needed to improve follow-up. Objectives The purpose of this study was to develop a decision-support software prototype enabling individual and system-wide tracking of abnormal test result alerts lacking follow-up, and to conduct formative evaluations, including usability testing. Methods We developed a working prototype software system, the Alert Watch And Response Engine (AWARE), to detect abnormal test result alerts lacking documented follow-up, and to present context-specific reminders to providers. Development and testing took place within the VA’s EHR and focused on four cancer-related abnormal test results. Design concepts emphasized mitigating the effects of high workload and alert fatigue while being minimally intrusive. We conducted a multifaceted formative evaluation of the software, addressing fit within the larger socio-technical system. Evaluations included usability testing with the prototype and interview questions about organizational and workflow factors. Participants included 23 physicians, 9 clinical information technology specialists, and 8 quality/safety managers. Results Evaluation results indicated that our software prototype fit within the technical environment and clinical workflow, and physicians were able to use it successfully. Quality/safety managers reported that the tool would be useful in future quality assurance activities to detect patients who lack documented follow-up. Additionally, we successfully installed the software on the local facility’s “test” EHR system, thus demonstrating technical compatibility. Conclusion To address the factors involved in missed

  19. Abnormal findings in peers during skills learning.

    PubMed

    Wearn, Andy; Nakatsuji, Miriam; Bhoopatkar, Harsh

    2017-02-01

    Peer physical examination (PPE), where students examine each other, is common in contemporary clinical skills learning. A range of benefits and risks have been explored in the literature. One persistent concern has been the identification and management of abnormal physical findings. Two previous studies have attempted to quantify the risk, one through the discussion of two exemplar cases and the other with a retrospective student survey. Here, we report the first prospective study of the number and type of abnormalities encountered as part of early clinical skills learning in a medical programme. We have a formal written consent process for PPE, which includes the management of abnormal findings through the completion of an event form. Our data come from cohorts undertaking years 2 and 3 of the programme between 2003 and 2014. One persistent concern (of PPE) has been the identification and management of abnormal physical findings RESULTS: Nineteen event forms were completed over this period. The incidence rates per year ranged from 0.23 to 1.05 per cent. Abnormal findings included raised blood pressure, heart murmur, abnormal bedside test values, and eye and skin conditions. The low event rate, along with a feasible process for dealing with this issue, goes some way to reassuring those with concerns. We acknowledge that some abnormalities may have been missed, and that some data may have been lost as a result of incorrect process; however, even the highest annual rate is low in absolute terms. We recommend a formal process for managing abnormalities. Ideally this would be part of an overall PPE written policy, communicated to students, enacted by tutors and approved by the local ethics committee. © 2016 John Wiley & Sons Ltd.

  20. Electrocardiogram abnormalities and coronary calcification in postmenopausal women.

    PubMed

    Sabour, Siamak; Grobbee, Diederick; Rutten, Annemarieke; Prokop, Mathias; Bartelink, Marie-Louise; van der Schouw, Yvonne; Bots, Michiel

    2010-01-01

    An electrocardiogram (ECG) can provide information on subclinical myocardial damage. The presence, and more importantly, the quantity of coronary artery calcification (CAC), relates well with the overall severity of the atherosclerotic process. A strong relation has been demonstrated between coronary calcium burden and the incidence of myocardial infarction, a relation independent of age. The aim of this study was to assess the relation of left ventricular hypertrophy (LVH) and ECG abnormalities with CAC. The study population comprised 566 postmenopausal women selected from a population-based cohort study. Information on LVH and repolarization abnormalities (T-axis and QRS-T angle) was obtained using electrocardiography. Modular ECG Analysis System (MEANS) was used to assess ECG abnormalities. The women underwent a multi detector-row computed tomography (MDCT) scan (Philips Mx 8000 IDT 16) to assess CAC. The Agatston score was used to quantify CAC; scores greater than zero were considered as the presence of coronary calcium. Logistic regression was used to assess the relation of ECG abnormality with coronary calcification. LVH was found in 2.7% (n = 15) of the women. The prevalence of T-axis abnormality was 6% (n = 34), whereas 8.5% (n = 48) had a QRS-T angle abnormality. CAC was found in 62% of the women. Compared to women with a normal T-axis, women with borderline or abnormal T-axes were 3.8 fold more likely to have CAC (95% CI: 1.4-10.2). Similarly, compared to women with a normal QRS-T angle, in women with borderline or abnormal QRS-T angle, CAC was 2.0 fold more likely to be present (95% CI: 1.0-4.1). Among women with ECG abnormalities reflecting subclinical ischemia, CAC is commonly found and may in part explain the increased coronary heart disease risk associated with these ECG abnormalities.

  1. Electrocardiogram Abnormalities and Coronary Calcification in Postmenopausal Women

    PubMed Central

    Sabour, Siamak; Grobbee, Diederick; Rutten, Annemarieke; Prokop, Mathias; Bartelink, Marie-Louise; van der Schouw, Yvonne; Bots, Michiel

    2010-01-01

    Background: An electrocardiogram (ECG) can provide information on subclinical myocardial damage. The presence, and more importantly, the quantity of coronary artery calcification (CAC), relates well with the overall severity of the atherosclerotic process. A strong relation has been demonstrated between coronary calcium burden and the incidence of myocardial infarction, a relation independent of age. The aim of this study was to assess the relation of left ventricular hypertrophy (LVH) and ECG abnormalities with CAC. Methods: The study population comprised 566 postmenopausal women selected from a population-based cohort study. Information on LVH and repolarization abnormalities (T-axis and QRS-T angle) was obtained using electrocardiography. Modular ECG Analysis System (MEANS) was used to assess ECG abnormalities. The women underwent a multi detector-row computed tomography (MDCT) scan (Philips Mx 8000 IDT 16) to assess CAC. The Agatston score was used to quantify CAC; scores greater than zero were considered as the presence of coronary calcium. Logistic regression was used to assess the relation of ECG abnormality with coronary calcification. Results: LVH was found in 2.7% (n = 15) of the women. The prevalence of T-axis abnormality was 6% (n = 34), whereas 8.5% (n = 48) had a QRS-T angle abnormality. CAC was found in 62% of the women. Compared to women with a normal T-axis, women with borderline or abnormal T-axes were 3.8 fold more likely to have CAC (95% CI: 1.4–10.2). Similarly, compared to women with a normal QRS-T angle, in women with borderline or abnormal QRS-T angle, CAC was 2.0 fold more likely to be present (95% CI: 1.0–4.1). Conclusion: Among women with ECG abnormalities reflecting subclinical ischemia, CAC is commonly found and may in part explain the increased coronary heart disease risk associated with these ECG abnormalities. PMID:23074563

  2. A systematic screen for morphological abnormalities during fission yeast sexual reproduction identifies a mechanism of actin aster formation for cell fusion

    PubMed Central

    Groux, Raphaël; Vincenzetti, Vincent

    2017-01-01

    In non-motile fungi, sexual reproduction relies on strong morphogenetic changes in response to pheromone signaling. We report here on a systematic screen for morphological abnormalities of the mating process in fission yeast Schizosaccharomyces pombe. We derived a homothallic (self-fertile) collection of viable deletions, which, upon visual screening, revealed a plethora of phenotypes affecting all stages of the mating process, including cell polarization, cell fusion and sporulation. Cell fusion relies on the formation of the fusion focus, an aster-like F-actin structure that is marked by strong local accumulation of the myosin V Myo52, which concentrates secretion at the fusion site. A secondary screen for fusion-defective mutants identified the myosin V Myo51-associated coiled-coil proteins Rng8 and Rng9 as critical for the coalescence of the fusion focus. Indeed, rng8Δ and rng9Δ mutant cells exhibit multiple stable dots at the cell-cell contact site, instead of the single focus observed in wildtype. Rng8 and Rng9 accumulate on the fusion focus, dependent on Myo51 and tropomyosin Cdc8. A tropomyosin mutant allele, which compromises Rng8/9 localization but not actin binding, similarly leads to multiple stable dots instead of a single focus. By contrast, myo51 deletion does not strongly affect fusion focus coalescence. We propose that focusing of the actin filaments in the fusion aster primarily relies on Rng8/9-dependent cross-linking of tropomyosin-actin filaments. PMID:28410370

  3. Abnormally phosphorylated tau protein related to the formation of neurofibrillary tangles and neuropil threads in the cerebral cortex of sheep and goat.

    PubMed

    Braak, H; Braak, E; Strothjohann, M

    1994-04-25

    Frontal sections including temporal isocortex, entorhinal region and hippocampus from aged domestic animals (dog, cat, horse, sheep and goat) were studied for Alzheimer-related changes using immunostaining with the AT8 antibody for abnormally phosphorylated tau protein and selective silver techniques for A4 amyloid and neurofibrillary changes of the Alzheimer type. The material available to us did not show A4 amyloid deposits or argyrophilic neurofibrillary changes. Only the brains of aged sheep and goat exhibited the presence of AT8-immunoreactive pyramidal cells in the entorhinal region and hippocampal formation. Two groups of AT8-positive neurons could be observed: The first group contained evenly distributed immunoreactive material in all parts of the soma, the dendrites and the axon. The neuronal processes appeared quite normal. The second group, however, showed conspicuous changes in the cellular processes consisting of a loss of immunoreactivity within the axon and the proximal dendrites and the appearance of intensely stained swellings within the curved distal dendrites. These changes were closely reminiscent to alterations of the cytoskeleton known to occur at the same location in the aging human brain and in Alzheimer's disease. The findings justify a closer look at sheep and goat when searching for suitable animal models for experimental studies of the conditions responsible for the development of Alzheimer-related neurofibrillary changes.

  4. Classification of breast abnormalities using artificial neural network

    NASA Astrophysics Data System (ADS)

    Zaman, Nur Atiqah Kamarul; Rahman, Wan Eny Zarina Wan Abdul; Jumaat, Abdul Kadir; Yasiran, Siti Salmah

    2015-05-01

    Classification is the process of recognition, differentiation and categorizing objects into groups. Breast abnormalities are calcifications which are tumor markers that indicate the presence of cancer in the breast. The aims of this research are to classify the types of breast abnormalities using artificial neural network (ANN) classifier and to evaluate the accuracy performance using receiver operating characteristics (ROC) curve. The methods used in this research are ANN for breast abnormalities classifications and Canny edge detector as a feature extraction method. Previously the ANN classifier provides only the number of benign and malignant cases without providing information for specific cases. However in this research, the type of abnormality for each image can be obtained. The existing MIAS MiniMammographic database classified the mammogram images into three features only namely characteristic of background tissues, class of abnormality and radius of abnormality. However, in this research three other features are added-in. These three features are number of spots, area and shape of abnormalities. Lastly the performance of the ANN classifier is evaluated using ROC curve. It is found that ANN has an accuracy of 97.9% which is considered acceptable.

  5. Abnormal Selective Attention Normalizes P3 Amplitudes in PDD

    ERIC Educational Resources Information Center

    Hoeksma, Marco R.; Kemner, Chantal; Kenemans, J. Leon; van Engeland, Herman

    2006-01-01

    This paper studied whether abnormal P3 amplitudes in PDD are a corollary of abnormalities in ERP components related to selective attention in visual and auditory tasks. Furthermore, this study sought to clarify possible age differences in such abnormalities. Children with PDD showed smaller P3 amplitudes than controls, but no abnormalities in…

  6. 42 CFR 37.54 - Notification of abnormal radiographic findings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., abnormality of cardiac shape or size, tuberculosis, lung cancer, or any other significant abnormal findings... shape or size, tuberculosis, cancer, complicated pneumoconiosis, and any other significant abnormal...

  7. Lenticular abnormalities in children.

    PubMed

    Khokhar, Sudarshan; Agarwal, Tushar; Kumar, Gaurav; Kushmesh, Rakhi; Tejwani, Lalit Kumar

    2012-01-01

    To study the lenticular problems in children presenting at an apex institute. Retrospective analysis of records (< 14 years) of new lens clinic cases was done. Of 1,047 children, 687 were males. Mean age at presentation was 6.35 ± 4.13 years. Developmental cataract was seen in 45.6% and posttraumatic cataract in 29.7% of patients. Other abnormalities were cataract with retinal detachment, persistent hyperplastic primary vitreous, subluxated lens, micro/spherophakia, cataract secondary to uveitis, intraocular lens complications, cataract with choroidal coloboma, and visual axis opacification. Developmental and posttraumatic cataracts were the most common abnormalities. Delayed presentation is of concern. Copyright 2012, SLACK Incorporated.

  8. Immune Abnormalities in Patients with Autism.

    ERIC Educational Resources Information Center

    Warren, Reed P.; And Others

    1986-01-01

    A study of 31 autistic patients (3-28 years old) has revealed several immune-system abnormalities, including decreased numbers of T lymphocytes and an altered ratio of helper-to-suppressor T cells. Immune-system abnormalities may be directly related to underlying biologic processes of autism or an indirect reflection of the actual pathologic…

  9. Qualitative metabolomics profiling of serum and bile from dogs with gallbladder mucocele formation.

    PubMed

    Gookin, Jody L; Mathews, Kyle G; Cullen, John; Seiler, Gabriela

    2018-01-01

    Mucocele formation is characterized by secretion of abnormally thick mucus by the gallbladder epithelium of dogs that may cause obstruction of the bile duct or rupture of the gallbladder. The disease is increasingly recognized and is associated with a high morbidity and mortality. The cause of gallbladder mucocele formation in dogs is unknown. There is a strong breed predisposition and affected dogs have a high incidence of concurrent endocrinopathy or hyperlipidemia. These observations suggest a significant influence of both genetic and metabolic factors on disease pathogenesis. In this study, we investigated a theory that mucocele formation is associated with a syndrome of metabolic disruption. We surmised that a global, untargeted metabolomics approach could provide unique insight into the systemic pathogenesis of gallbladder mucocele formation and identify specific compounds as candidate biomarkers or treatment targets. Moreover, concurrent examination of the serum and hepatic duct bile metabolome would enable the construction of mechanism-based theories or identification of specific compounds responsible for altered function of the gallbladder epithelium. Abnormalities observed in dogs with gallbladder mucocele formation, including a 33-fold decrease in serum adenosine 5'-monophosphate (AMP), lower quantities of precursors required for synthesis of energy transporting nucleotides, and increases in citric acid cycle intermediates, suggest excess metabolic energy and a carbon surplus. Altered quantities of compounds involved in protein translation and RNA turnover, together with accumulation of gamma-glutamylated and N-acetylated amino acids in serum suggest abnormal regulation of protein and amino acid metabolism. Increases in lathosterol and 7α-hydroxycholesterol suggest a primary increase in cholesterol synthesis and diversion to bile acid formation. A number of specific biomarker compounds were identified for their ability to distinguish between control

  10. Abnormal placentation.

    PubMed

    Bauer, Samuel T; Bonanno, Clarissa

    2009-04-01

    Abnormal placentation poses a diagnostic and treatment challenge for all providers caring for pregnant women. As one of the leading causes of postpartum hemorrhage, abnormal placentation involves the attachment of placental villi directly to the myometrium with potentially deeper invasion into the uterine wall or surrounding organs. Surgical procedures that disrupt the integrity of uterus, including cesarean section, dilatation and curettage, and myomectomy, have been implicated as key risk factors for placenta accreta. The diagnosis is typically made by gray-scale ultrasound and confirmed with magnetic resonance imaging, which may better delineate the extent of placental invasion. It is critical to make the diagnosis before delivery because preoperative planning can significantly decrease blood loss and avoid substantial morbidity associated with placenta accreta. Aggressive management of hemorrhage through the use of uterotonics, fluid resuscitation, blood products, planned hysterectomy, and surgical hemostatic agents can be life-saving for these patients. Conservative management, including the use of uterine and placental preservation and subsequent methotrexate therapy or pelvic artery embolization, may be considered when a focal accreta is suspected; however, surgical management remains the current standard of care.

  11. Electrocardiographic abnormalities in amateur male marathon runners.

    PubMed

    Kaleta, Anna M; Lewicka, Ewa; Dąbrowska-Kugacka, Alicja; Lewicka-Potocka, Zuzanna; Wabich, Elżbieta; Szerszyńska, Anna; Dyda, Julia; Sobolewski, Jakub; Koenner, Jakub; Raczak, Grzegorz

    2018-06-18

    Sports activity has become extremely popular among amateurs. Electrocardiography is a useful tool in screening for cardiac pathologies in athletes; however, there is little data on electrocardiographic abnormalities in the group of amateur athletes. The aim of this study was to analyze the abnormalities in resting and exercise electrocardiograms (ECGs) in a group of amateur athletes, and try to determine whether the criteria applied for the general population or for athletes' ECGs should be implemented in this group. In 40 amateur male marathon runners, 3 consecutive 12-lead ECGs were performed: 2-3 weeks before (stage 1), just after the run (stage 2) and 2-3 weeks after the marathon (stage 3). Resting (stage 1) and exercise (stage 2) ECGs were analyzed following the refined criteria for the assessment of athlete's ECG (changes classified as training-related, borderline or training-unrelated). In resting ECGs, at least 1 abnormality was found in 92.5% of the subjects and the most common was sinus bradycardia (62.5%). In post-exercise ECGs, at least 1 abnormality was present in 77.5% of the subjects and the most common was right atrium enlargement (RAE) (42.5%). Training-related ECG variants were more frequent at rest (82.5% vs 42.5%; p = 0.0008), while borderline variants - after the run (22.5% vs 57.5%; p = 0.0004). Training-unrelated abnormalities were found in 15% and 10% of the subjects, respectively (p-value - nonsignificant), and the most common was T-wave inversion. Even if the refined criteria rather than the criteria used for normal sedentary population were applied, the vast majority of amateur runners showed at least 1 abnormality in resting ECGs, which were mainly training-related variants. However, at rest, in 15% of the subjects, pathologic training-unrelated abnormalities were found. The most frequent post-exercise abnormality was right atrial enlargement. General electrocardiographic screening in amateur athletes should be taken into consideration.

  12. Hierarchical TiO2/C nanocomposite monoliths with a robust scaffolding architecture, mesopore-macropore network and TiO2-C heterostructure for high-performance lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Huang, Hai-Bo; Yang, Yue; Chen, Li-Hua; Wang, Yun; Huang, Shao-Zhuan; Tao, Jia-Wei; Ma, Xiao-Ting; Hasan, Tawfique; Li, Yu; Xu, Yan; Su, Bao-Lian

    2016-05-01

    Engineering hierarchical structures of electrode materials is a powerful strategy for optimizing the electrochemical performance of an anode material for lithium-ion batteries (LIBs). Herein, we report the fabrication of hierarchical TiO2/C nanocomposite monoliths by mediated mineralization and carbonization using bacterial cellulose (BC) as a scaffolding template as well as a carbon source. TiO2/C has a robust scaffolding architecture, a mesopore-macropore network and TiO2-C heterostructure. TiO2/C-500, obtained by calcination at 500 °C in nitrogen, contains an anatase TiO2-C heterostructure with a specific surface area of 66.5 m2 g-1. When evaluated as an anode material at 0.5 C, TiO2/C-500 exhibits a high and reversible lithium storage capacity of 188 mA h g-1, an excellent initial capacity of 283 mA h g-1, a long cycle life with a 94% coulombic efficiency preserved after 200 cycles, and a very low charge transfer resistance. The superior electrochemical performance of TiO2/C-500 is attributed to the synergistic effect of high electrical conductivity, anatase TiO2-C heterostructure, mesopore-macropore network and robust scaffolding architecture. The current material strategy affords a general approach for the design of complex inorganic nanocomposites with structural stability, and tunable and interconnected hierarchical porosity that may lead to the next generation of electrochemical supercapacitors with high energy efficiency and superior power density.Engineering hierarchical structures of electrode materials is a powerful strategy for optimizing the electrochemical performance of an anode material for lithium-ion batteries (LIBs). Herein, we report the fabrication of hierarchical TiO2/C nanocomposite monoliths by mediated mineralization and carbonization using bacterial cellulose (BC) as a scaffolding template as well as a carbon source. TiO2/C has a robust scaffolding architecture, a mesopore-macropore network and TiO2-C heterostructure. TiO2/C-500

  13. Bone and heart abnormalities of subclinical hyperthyroidism in women below the age of 65 years.

    PubMed

    Rosario, Pedro Weslley

    2008-12-01

    The objective of the present study was to evaluate bone and cardiac abnormalities and symptoms and signs of thyroid hormone excess in women with subclinical hyperthyroidism (SCH) aged < 65 years. Forty-eight women with SCH were evaluated. The control group consisted of 48 euthyroid volunteers. The mean symptom rating scale score was significantly higher in patients. Cardiac involvement, both morphological and affecting systolic and diastolic functions, was also observed in patients. Women with SCH showed a significant increase in serum markers of bone formation and resorption. In addition, bone mineral density (BMD) was lower in the femoral neck but not in the lumbar spine in patients before menopause, whereas a lower BMD was observed at both sites in postmenopausal patients. SCH is not completely asymptomatic in women aged < 65 years, and is associated with heart abnormalities and with increased bone turnover and reduced BMD even before menopause.

  14. 3D macroporous electrode and high-performance in lithium-ion batteries using SnO2 coated on Cu foam

    PubMed Central

    Um, Ji Hyun; Choi, Myounggeun; Park, Hyeji; Cho, Yong-Hun; Dunand, David C.; Choe, Heeman; Sung, Yung-Eun

    2016-01-01

    A three-dimensional porous architecture makes an attractive electrode structure, as it has an intrinsic structural integrity and an ability to buffer stress in lithium-ion batteries caused by the large volume changes in high-capacity anode materials during cycling. Here we report the first demonstration of a SnO2-coated macroporous Cu foam anode by employing a facile and scalable combination of directional freeze-casting and sol-gel coating processes. The three-dimensional interconnected anode is composed of aligned microscale channels separated by SnO2-coated Cu walls and much finer micrometer pores, adding to surface area and providing space for volume expansion of SnO2 coating layer. With this anode, we achieve a high reversible capacity of 750 mAh g−1 at current rate of 0.5 C after 50 cycles and an excellent rate capability of 590 mAh g−1 at 2 C, which is close to the best performance of Sn-based nanoscale material so far. PMID:26725652

  15. Cardiac abnormality prediction using HMLP network

    NASA Astrophysics Data System (ADS)

    Adnan, Ja'afar; Ahmad, K. A.; Mat, Muhamad Hadzren; Rizman, Zairi Ismael; Ahmad, Shahril

    2018-02-01

    Cardiac abnormality often occurs regardless of gender, age and races but depends on the lifestyle. This problem sometimes does not show any symptoms and usually detected once it already critical which lead to a sudden death to the patient. Basically, cardiac abnormality is the irregular electrical signal that generate by the pacemaker of the heart. This paper attempts to develop a program that can detect cardiac abnormality activity through implementation of Hybrid Multilayer Perceptron (HMLP) network. A certain amount of data of the heartbeat signals from the electrocardiogram (ECG) will be used in this project to train the MLP and HMLP network by using Modified Recursive Prediction Error (MRPE) algorithm and to test the network performance.

  16. Four families with immunodeficiency and chromosome abnormalities.

    PubMed Central

    Candy, D C; Hayward, A R; Hughes, D T; Layward, L; Soothill, J F

    1979-01-01

    Six children, with severe deficiency of some or all of the immunoglobulins and minor somatic abnormalities, had chromosomal abnormalities: (1) 45,XY,t(13q/18q), (2) 46,XY,21ps +, (3) two brothers 46,XY (inv. 7) (4) 45,X,t(11p/10p)/46X,iXq,t(11p/10p) and, (5) in addendum, 45,XX,-18;46,XX, r18. The chromosome abnormalities were detected in B- as well as T-lymphocytes (as evidenced by using both PHA- and PWM-stimulated cultures) in all probands, but one was mosaic in PHA culture, although all his PWM-stimulated cells were abnormal. Chromosomal variants were also detected in relatives of three and immunodeficiency in relatives of two. Images Fig. 1 Fig. 3 PMID:314782

  17. Identification of abnormal accident patterns at intersections

    DOT National Transportation Integrated Search

    1999-08-01

    This report presents the findings and recommendations based on the Identification of Abnormal Accident Patterns at Intersections. This project used a statistically valid sampling method to determine whether a specific intersection has an abnormally h...

  18. Prediction of heart abnormality using MLP network

    NASA Astrophysics Data System (ADS)

    Hashim, Fakroul Ridzuan; Januar, Yulni; Mat, Muhammad Hadzren; Rizman, Zairi Ismael; Awang, Mat Kamil

    2018-02-01

    Heart abnormality does not choose gender, age and races when it strikes. With no warning signs or symptoms, it can result to a sudden death of the patient. Generally, heart's irregular electrical activity is defined as heart abnormality. Via implementation of Multilayer Perceptron (MLP) network, this paper tries to develop a program that allows the detection of heart abnormality activity. Utilizing several training algorithms with Purelin activation function, an amount of heartbeat signals received through the electrocardiogram (ECG) will be employed to condition the MLP network.

  19. Genetics Home Reference: X-linked lissencephaly with abnormal genitalia

    MedlinePlus

    ... Health Conditions X-linked lissencephaly with abnormal genitalia X-linked lissencephaly with abnormal genitalia Printable PDF Open ... Javascript to view the expand/collapse boxes. Description X-linked lissencephaly with abnormal genitalia (XLAG) is a ...

  20. Complex patterns of abnormal heartbeats

    NASA Technical Reports Server (NTRS)

    Schulte-Frohlinde, Verena; Ashkenazy, Yosef; Goldberger, Ary L.; Ivanov, Plamen Ch; Costa, Madalena; Morley-Davies, Adrian; Stanley, H. Eugene; Glass, Leon

    2002-01-01

    Individuals having frequent abnormal heartbeats interspersed with normal heartbeats may be at an increased risk of sudden cardiac death. However, mechanistic understanding of such cardiac arrhythmias is limited. We present a visual and qualitative method to display statistical properties of abnormal heartbeats. We introduce dynamical "heartprints" which reveal characteristic patterns in long clinical records encompassing approximately 10(5) heartbeats and may provide information about underlying mechanisms. We test if these dynamics can be reproduced by model simulations in which abnormal heartbeats are generated (i) randomly, (ii) at a fixed time interval following a preceding normal heartbeat, or (iii) by an independent oscillator that may or may not interact with the normal heartbeat. We compare the results of these three models and test their limitations to comprehensively simulate the statistical features of selected clinical records. This work introduces methods that can be used to test mathematical models of arrhythmogenesis and to develop a new understanding of underlying electrophysiologic mechanisms of cardiac arrhythmia.

  1. High lifetime probability of screen-detected cervical abnormalities.

    PubMed

    Pankakoski, Maiju; Heinävaara, Sirpa; Sarkeala, Tytti; Anttila, Ahti

    2017-12-01

    Objective Regular screening and follow-up is an important key to cervical cancer prevention; however, screening inevitably detects mild or borderline abnormalities that would never progress to a more severe stage. We analysed the cumulative probability and recurrence of cervical abnormalities in the Finnish organized screening programme during a 22-year follow-up. Methods Screening histories were collected for 364,487 women born between 1950 and 1965. Data consisted of 1 207,017 routine screens and 88,143 follow-up screens between 1991 and 2012. Probabilities of cervical abnormalities by age were estimated using logistic regression and generalized estimating equations methodology. Results The probability of experiencing any abnormality at least once at ages 30-64 was 34.0% (95% confidence interval [CI]: 33.3-34.6%) . Probability was 5.4% (95% CI: 5.0-5.8%) for results warranting referral and 2.2% (95% CI: 2.0-2.4%) for results with histologically confirmed findings. Previous occurrences were associated with an increased risk of detecting new ones, specifically in older women. Conclusion A considerable proportion of women experience at least one abnormal screening result during their lifetime, and yet very few eventually develop an actual precancerous lesion. Re-evaluation of diagnostic criteria concerning mild abnormalities might improve the balance of harms and benefits of screening. Special monitoring of women with recurrent abnormalities especially at older ages may also be needed.

  2. [Abnormal cervicovaginal cytology in women with rheumatoid arthritis].

    PubMed

    Mercado, Ulises

    2010-02-01

    Patients with rheumatoid arthritis (RA) are at increased risk of infections and cancer. A link between RA and abnormal cervicovaginal cytology has rarely been reported. The aim of this study was to review cervicovaginal cytology results in women with RA and compare them with a control population. Sexual behavior also was investigated. Cervicovaginal cytology results of 95 women with RA were compared to those of a control population of 1,719 women attending at the same hospital and followed until June 2009. Records of RA patients were reviewed to obtain clinical data, particularly sexual behavior. Of 95 RA patients, 13/95 had an abnormal cervicovaginal cytology result, compared with 120/1,719 controls. Twelve/13 had squamous intraepithelial lesions (SIL), compared with 27/120 controls. There was no significant difference in sexual partners between women with RA and controls. Women with RA without abnormal cervicovaginal cytology had less sexual partners than those with RA and abnormal cytology. Two women with RA and abnormal cervicovaginal cytology had a history of condylomata and herpes genital. Three/13 women with RA developed abnormal cervicovaginal cytology after 12 to 36 months initiating their illness. None from them had ever received immunosuppressants. Women with RA have an increased prevalence of abnormal cervical cytology, compared with a control population. It may be related to chronic inflammatory disease and sexual behavior.

  3. Abnormalities of High Density Lipoproteins in Abetalipoproteinemia*

    PubMed Central

    Jones, John W.; Ways, Peter

    1967-01-01

    Detailed studies of the high density lipoproteins from three patients with abetalipoproteinemia have revealed the following principal abnormalities: 1) High density lipoprotein 3 (HDL3) is reduced in both absolute and relative concentration, although HDL2 is present in normal amounts. 2) The phospholipid distribution of both HDL fractions is abnormal, with low concentrations of lecithin and an increased percentage (though normal absolute quantity) of sphingomyelin. 3) In both HDL fractions, lecithin contains less linoleate and more oleate than normal. The cholesteryl esters are also low in linoleic acid, and the sphingomyelin is high in nervonic acid. Dietary intake influences the linoleic acid concentration within 2 weeks, and perhaps sooner, but the elevated sphingomyelin nervonic acid is little affected by up to 6 months of corn oil supplementation. Qualitatively similar changes in fatty acid composition, but not phospholipid distribution, are also found in other malabsorption states. The available evidence suggests that the abnormally low levels of HDL3 and the deranged phospholipid distribution are more specific for abetalipoproteinemia than the fatty acid abnormalities. However, the absence of these abnormalities in obligate heterozygous subjects makes their relationship to the primary defect of abetalipoproteinemia difficult to assess. Images PMID:6027078

  4. Endocrine abnormalities in lithium toxicity.

    PubMed

    Shanks, Gabriella; Mishra, Vinita; Nikolova, Stanka

    2017-10-01

    Lithium toxicity can manifest as a variety of biochemical -abnormalities. This case report describes a patient -presenting to the emergency department with neuropsychiatric -symptoms on a background of bipolar disorder, for which she was prescribed lithium for 26 years previously. Cases of lithium toxicity are rare but can be severe and this case report -demonstrates to clinicians that they must be thorough in investigating patients with lithium toxicity, as there are many potential abnormalities that can manifest concurrently. © Royal College of Physicians 2017. All rights reserved.

  5. Brain and bone abnormalities of thanatophoric dwarfism.

    PubMed

    Miller, Elka; Blaser, Susan; Shannon, Patrick; Widjaja, Elysa

    2009-01-01

    The purpose of this article is to present the imaging findings of skeletal and brain abnormalities in thanatophoric dwarfism, a lethal form of dysplastic dwarfism. The bony abnormalities associated with thanatophoric dwarfism include marked shortening of the tubular bones and ribs. Abnormal temporal lobe development is a common associated feature and can be visualized as early as the second trimester. It is important to assess the brains of fetuses with suspected thanatophoric dwarfism because the presence of associated brain malformations can assist in the antenatal diagnosis of thanatophoric dwarfism.

  6. Chromosomal abnormalities as a cause of recurrent abortions in Egypt

    PubMed Central

    El-Dahtory, Faeza Abdel Mogib

    2011-01-01

    BACKGROUND: In 4%-8% of couples with recurrent abortion, at least one of the partners has chromosomal abnormality. Most spontaneous miscarriages which happen in the first and second trimesters are caused by chromosomal abnormalities. These chromosomal abnormalities may be either numerical or structural. MATERIAL AND METHODS: Cytogenetic study was done for 73 Egyptian couples who presented with recurrent abortion at Genetic Unit of Children Hospital, Mansoura University. RESULTS: We found that the frequency of chromosomal abnormalities was not significantly different from that reported worldwide. Chromosomal abnormalities were detected in 9 (6.1%) of 73 couples. Seven of chromosomal abnormalities were structural and two of them were numerical. CONCLUSION: Our results showed that 6.1% of the couples with recurrent abortion had chromosomal abnormalities, with no other abnormalities. We suggest that it is necessary to perform cytogenetic in vestigation for couples who have recurrent abortion. PMID:22090718

  7. Upregulation of proinflammatory genes in skin lesions may be the cause of keloid formation (Review)

    PubMed Central

    DONG, XIANGLIN; MAO, SHAOLIN; WEN, HAO

    2013-01-01

    It was previously demonstrated that the main cause behind keloid formation may be keloid fibroblast abnormalities, which are closely associated with the microenvironment of the keloid lesion. The post-traumatic and chronic inflammation of the keloid lesion area suggest that inflammatory mediators play an important role in the keloid microenvironment and are crucial for keloid fibroblast abnormalities. In this study, we hypothesized that the mechanism underlying keloid formation may involve the continuous upregulation of proinflammatory gene expression in keloid lesions. This hypothesis may explain the inflammatory response, invasive growth and recurrence following resection of keloids, as well as the selective localization of keloids in specific parts of a patient’s body and the differences in localization among different patients. PMID:24649037

  8. Abnormal early cleavage events predict early embryo demise: sperm oxidative stress and early abnormal cleavage.

    PubMed

    Burruel, Victoria; Klooster, Katie; Barker, Christopher M; Pera, Renee Reijo; Meyers, Stuart

    2014-10-13

    Human embryos resulting from abnormal early cleavage can result in aneuploidy and failure to develop normally to the blastocyst stage. The nature of paternal influence on early embryo development has not been directly demonstrated although many studies have suggested effects from spermatozoal chromatin packaging, DNA damage, centriolar and mitotic spindle integrity, and plasma membrane integrity. The goal of this study was to determine whether early developmental events were affected by oxidative damage to the fertilizing sperm. Survival analysis was used to compare patterns of blastocyst formation based on P2 duration. Kaplan-Meier survival curves demonstrate that relatively few embryos with short (<1 hr) P2 times reached blastocysts, and the two curves diverged beginning on day 4, with nearly all of the embryos with longer P2 times reaching blastocysts by day 6 (p < .01). We determined that duration of the 2nd to 3rd mitoses were sensitive periods in the presence of spermatozoal oxidative stress. Embryos that displayed either too long or too short cytokineses demonstrated an increased failure to reach blastocyst stage and therefore survive for further development. Although paternal-derived gene expression occurs later in development, this study suggests a specific role in early mitosis that is highly influenced by paternal factors.

  9. Ice as a Green-Structure-Directing Agent in the Synthesis of Macroporous MWCNTs and Chondroitin Sulphate Composites.

    PubMed

    Nardecchia, Stefania; Serrano, María Concepción; García-Argüelles, Sara; Maia Da Costa, Marcelo E H; Ferrer, María Luisa; Gutiérrez, María C

    2017-03-28

    The incorporation of multi-walled carbon nanotubes (MWCNTs) into chondroitin sulphate-based scaffolds and the effect on the structural, mechanical, conductive, and thermal properties of the resulting scaffolds is investigated. Three-dimensional hierarchical materials are prepared upon the application of the ice segregation-induced self-assembly (ISISA) process. The use of ice as structure-directing agents avoids chemicals typically used for this purpose (e.g., surfactants, block copolymers, etc.), hence, emphasising the green features of this soft-templating approach. We determine the critical parameters that control the morphology of the scaffolds formed upon ice-templating (i.e., MWCNTs type, freezing conditions, polymer and MWCNT concentration). MWCNTs are surface functionalized by acidic treatment. MWCNT functionalization is characterized by Raman, Fourier transfer infrared (FTIR) and X-ray Photoelectron (XPS) spectroscopies. Scanning electron microscopy (SEM) analysis and porosity studies reveal that MWCNT content modifies the morphology of the macroporous structure, which decreases by increasing MWCNT concentration. Differences in scaffold morphology should be translated into their conductivity and mechanical properties. As a general trend, the Young's modulus and the electrical conductivity of the scaffolds increase with the MWCNT content. Preliminary biocompatibility tests with human osteoblast-like cells also reveal the capability of these structures to support cell growth.

  10. Ice as a Green-Structure-Directing Agent in the Synthesis of Macroporous MWCNTs and Chondroitin Sulphate Composites

    PubMed Central

    Nardecchia, Stefania; Serrano, María Concepción; García-Argüelles, Sara; Maia Da Costa, Marcelo E. H.; Ferrer, María Luisa; Gutiérrez, María C.

    2017-01-01

    The incorporation of multi-walled carbon nanotubes (MWCNTs) into chondroitin sulphate-based scaffolds and the effect on the structural, mechanical, conductive, and thermal properties of the resulting scaffolds is investigated. Three-dimensional hierarchical materials are prepared upon the application of the ice segregation-induced self-assembly (ISISA) process. The use of ice as structure-directing agents avoids chemicals typically used for this purpose (e.g., surfactants, block copolymers, etc.), hence, emphasising the green features of this soft-templating approach. We determine the critical parameters that control the morphology of the scaffolds formed upon ice-templating (i.e., MWCNTs type, freezing conditions, polymer and MWCNT concentration). MWCNTs are surface functionalized by acidic treatment. MWCNT functionalization is characterized by Raman, Fourier transfer infrared (FTIR) and X-ray Photoelectron (XPS) spectroscopies. Scanning electron microscopy (SEM) analysis and porosity studies reveal that MWCNT content modifies the morphology of the macroporous structure, which decreases by increasing MWCNT concentration. Differences in scaffold morphology should be translated into their conductivity and mechanical properties. As a general trend, the Young’s modulus and the electrical conductivity of the scaffolds increase with the MWCNT content. Preliminary biocompatibility tests with human osteoblast-like cells also reveal the capability of these structures to support cell growth. PMID:28772715

  11. Cortical gyrification is abnormal in children with prenatal alcohol exposure.

    PubMed

    Hendrickson, Timothy J; Mueller, Bryon A; Sowell, Elizabeth R; Mattson, Sarah N; Coles, Claire D; Kable, Julie A; Jones, Kenneth L; Boys, Christopher J; Lim, Kelvin O; Riley, Edward P; Wozniak, Jeffrey R

    2017-01-01

    Prenatal alcohol exposure (PAE) adversely affects early brain development. Previous studies have shown a wide range of structural and functional abnormalities in children and adolescents with PAE. The current study adds to the existing literature specifically on cortical development by examining cortical gyrification in a large sample of children with PAE compared to controls. Relationships between cortical development and intellectual functioning are also examined. Included were 92 children with PAE and 83 controls ages 9-16 from four sites in the Collaborative Initiative on FASD (CIFASD). All PAE participants had documented heavy PAE. All underwent a formal evaluation of physical anomalies and dysmorphic facial features. MRI data were collected using modified matched protocols on three platforms (Siemens, GE, and Philips). Cortical gyrification was examined using a semi-automated procedure. Whole brain group comparisons using Monte Carlo z-simulation for multiple comparisons showed significantly lower cortical gyrification across a large proportion of the cerebral cortex amongst PAE compared to controls. Whole brain comparisons and ROI based analyses showed strong positive correlations between cortical gyrification and IQ (i.e. less developed cortex was associated with lower IQ). Abnormalities in cortical development were seen across the brain in children with PAE compared to controls. Cortical gyrification and IQ were strongly correlated, suggesting that examining mechanisms by which alcohol disrupts cortical formation may yield clinically relevant insights and potential directions for early intervention.

  12. Evidence that abnormal grain growth precedes fatigue crack initiation in nanocrystalline Ni-Fe

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

    Furnish, Timothy A.; Bufford, Daniel C.; Ren, Fang

    Prior studies on the high-cycle fatigue behavior of nanocrystalline metals have shown that fatigue fracture is associated with abnormal grain growth (AGG). However, those previous studies have been unable to determine if AGG precedes fatigue crack initiation, or vice-versa. The present study shows that AGG indeed occurs prior to crack formation in nanocrystalline Ni-Fe by using a recently developed synchrotron X-ray diffraction modality that has been adapted for in-situ analysis. The technique allows fatigue tests to be interrupted at the initial signs of the AGG process, and subsequent microscopy reveals the precursor damage state preceding crack initiation.

  13. Evidence that abnormal grain growth precedes fatigue crack initiation in nanocrystalline Ni-Fe

    DOE PAGES

    Furnish, Timothy A.; Bufford, Daniel C.; Ren, Fang; ...

    2018-09-06

    Prior studies on the high-cycle fatigue behavior of nanocrystalline metals have shown that fatigue fracture is associated with abnormal grain growth (AGG). However, those previous studies have been unable to determine if AGG precedes fatigue crack initiation, or vice-versa. The present study shows that AGG indeed occurs prior to crack formation in nanocrystalline Ni-Fe by using a recently developed synchrotron X-ray diffraction modality that has been adapted for in-situ analysis. The technique allows fatigue tests to be interrupted at the initial signs of the AGG process, and subsequent microscopy reveals the precursor damage state preceding crack initiation.

  14. Influence of Pore Structure on the Effectiveness of a Biogenic Carbonate Surface Treatment for Limestone Conservation ▿

    PubMed Central

    De Muynck, Willem; Leuridan, Stijn; Van Loo, Denis; Verbeken, Kim; Cnudde, Veerle; De Belie, Nele; Verstraete, Willy

    2011-01-01

    A ureolytic biodeposition treatment was applied to five types of limestone in order to investigate the effect of pore structure on the protective performance of a biogenic carbonate surface treatment. Protective performance was assessed by means of transport and degradation processes, and the penetration depth of the treatment was visualized by microtomography. Pore size governs bacterial adsorption and hence the location and amount of carbonate precipitated. This study indicated that in macroporous stone, biogenic carbonate formation occurred to a larger extent and at greater depths than in microporous stone. As a consequence, the biodeposition treatment exhibited the greatest protective performance on macroporous stone. While precipitation was limited to the outer surface of microporous stone, biogenic carbonate formation occurred at depths of greater than 2 mm for Savonnières and Euville. For Savonnières, the presence of biogenic carbonate resulted in a 20-fold decreased rate of water absorption, which resulted in increased resistance to sodium sulfate attack and to freezing and thawing. While untreated samples were completely degraded after 15 cycles of salt attack, no damage was observed in biodeposition-treated Savonnières. From this study, it is clear that biodeposition is very effective and more feasible for macroporous stones than for microporous stones. PMID:21821746

  15. Influence of pore structure on the effectiveness of a biogenic carbonate surface treatment for limestone conservation.

    PubMed

    De Muynck, Willem; Leuridan, Stijn; Van Loo, Denis; Verbeken, Kim; Cnudde, Veerle; De Belie, Nele; Verstraete, Willy

    2011-10-01

    A ureolytic biodeposition treatment was applied to five types of limestone in order to investigate the effect of pore structure on the protective performance of a biogenic carbonate surface treatment. Protective performance was assessed by means of transport and degradation processes, and the penetration depth of the treatment was visualized by microtomography. Pore size governs bacterial adsorption and hence the location and amount of carbonate precipitated. This study indicated that in macroporous stone, biogenic carbonate formation occurred to a larger extent and at greater depths than in microporous stone. As a consequence, the biodeposition treatment exhibited the greatest protective performance on macroporous stone. While precipitation was limited to the outer surface of microporous stone, biogenic carbonate formation occurred at depths of greater than 2 mm for Savonnières and Euville. For Savonnières, the presence of biogenic carbonate resulted in a 20-fold decreased rate of water absorption, which resulted in increased resistance to sodium sulfate attack and to freezing and thawing. While untreated samples were completely degraded after 15 cycles of salt attack, no damage was observed in biodeposition-treated Savonnières. From this study, it is clear that biodeposition is very effective and more feasible for macroporous stones than for microporous stones.

  16. CHRONIC PERCHLORATE EXPOSURE CAUSES MORPHOLOGICAL ABNORMALITIES IN DEVELOPING STICKLEBACK

    PubMed Central

    Bernhardt, Richard R.; Von Hippel, Frank A.; O’Hara, Todd M.

    2011-01-01

    Few studies have examined the effects of chronic perchlorate exposure during growth and development, and fewer still have analyzed the effects of perchlorate over multiple generations. We describe morphological and developmental characteristics for threespine stickleback (Gasterosteus aculeatus) that were spawned and raised to sexual maturity in perchlorate-treated water (G1,2003) and for their offspring (G2,2004) that were not directly treated with perchlorate. The G1,2003 displayed a variety of abnormalities, including impaired formation of calcified traits, slower growth rates, aberrant sexual development, poor survivorship, and reduced pigmentation that allowed internal organs to be visible. Yet these conditions were absent when the offspring of contaminated fish (G2,2004) were raised in untreated water, suggesting a lack of transgenerational effects and that surviving populations may be able to recover following remediation of perchlorate-contaminated sites PMID:21465539

  17. Hemostatic Abnormalities in Multiple Myeloma Patients

    PubMed Central

    Gogia, Aarti; Sikka, Meera; Sharma, Satender; Rusia, Usha

    2018-01-01

    Background: Multiple myeloma (MM) is a neoplastic plasma cell disorder characterized by clonal proliferation of plasma cells in the bone marrow. Diverse hemostatic abnormalities have been reported in patients with myeloma which predispose to bleeding and also thrombosis. Methods: Complete blood count, biochemical parameters and parameters of hemostasis i.e. platelet count, prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), factor VIII assay results, plasma fibrinogen, D-dimer and lupus anticoagulant, were assessed in 29 MM patients and 30 age matched controls. Results: The most frequent abnormal screening parameter was APTT. Of the six indicative of a bleeding tendency i.e. thrombocytopenia, prolonged PT, APTT, TT, reduced plasma fibrinogen and factor VIII, at least one was abnormal in 8 (27.6%) patients. Of the four prothrombotic markers, lupus anticoagulant, D-dimer, elevated factor VIII and plasma fibrinogen, one or more marker was present in 24 (82.7%). D-dimer was the most common prothrombotic marker, being elevated in 22 (75.9%) patients. One or more laboratory parameter of hemostasis was abnormal in all 29 (100%) patients. Though thrombotic complications are reported to be less frequent as compared to hemorrhagic manifestations, one or more marker of thrombosis was present in 24 (82.7%) patients. Conclusion: This study provided laboratory evidence of hemostatic dysfunction which may be associated with thrombotic or bleeding complications at diagnosis in all MM patients. Hence, screening for these abnormalities at the time of diagnosis should help improved prognosis in such cases. PMID:29373903

  18. Preparation of epoxy-based macroporous monolithic columns for the fast and efficient immunofiltration of Staphylococcus aureus.

    PubMed

    Ott, Sonja; Niessner, Reinhard; Seidel, Michael

    2011-08-01

    Macroporous epoxy-based monolithic columns were used for immunofiltration of bacteria. The prepared monolithic polymer support is hydrophilic and has large pore sizes of 21 μm without mesopores. A surface chemistry usually applied for immobilization of antibodies on glass slides is successfully transferred to monolithic columns. Step-by-step, the surface of the epoxy-based monolith is hydrolyzed, silanized, coated with poly(ethylene glycol diamine) and activated with the homobifunctional crosslinker di(N-succinimidyl)carbonate for immobilization of antibodies on the monolithic columns. The functionalization steps are characterized to ensure the coating of each monolayer. The prepared antibody-immobilized monolithic column is optimized for immunofiltration to enrich Staphylococcus aureus as an important food contaminant. Different kinds of geometries of monolithic columns, flow rates and elution buffers are tested with the goal to get high recoveries in the shortest enrichment time as possible. An effective capture of S. aureus was achieved at a flow rate of 7.0 mL/min with low backpressures of 20.1±5.4 mbar enabling a volumetric enrichment of 1000 within 145 min. The bacteria were quantified by flow cytometry using a double-labeling approach. After immunofiltration the sensitivity was significantly increased and a detection limit of the total system of 42 S. aureus/mL was reached. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Abnormal tau phosphorylation in the thorny excrescences of CA3 hippocampal neurons in patients with Alzheimer's disease.

    PubMed

    Blazquez-Llorca, Lidia; Garcia-Marin, Virginia; Merino-Serrais, Paula; Ávila, Jesús; DeFelipe, Javier

    2011-01-01

    A key symptom in the early stages of Alzheimer's disease (AD) is the loss of declarative memory. The anatomical substrate that supports this kind of memory involves the neural circuits of the medial temporal lobe, and in particular, of the hippocampal formation and adjacent cortex. A main feature of AD is the abnormal phosphorylation of the tau protein and the presence of tangles. The sequence of cellular changes related to tau phosphorylation and tangle formation has been studied with an antibody that binds to diffuse phosphotau (AT8). Moreover, another tau antibody (PHF-1) has been used to follow the pathway of neurofibrillary (tau aggregation) degeneration in AD. We have used a variety of quantitative immunocytochemical techniques and confocal microscopy to visualize and characterize neurons labeled with AT8 and PHF-1 antibodies. We present here the rather unexpected discovery that in AD, there is conspicuous abnormal phosphorylation of the tau protein in a selective subset of dendritic spines. We identified these spines as the typical thorny excrescences of hippocampal CA3 neurons in a pre-tangle state. Since thorny excrescences represent a major synaptic target of granule cell axons (mossy fibers), such aberrant phosphorylation may play an essential role in the memory impairment typical of AD patients.

  20. Prevention of congenital abnormalities by periconceptional multivitamin supplementation.

    PubMed Central

    Czeizel, A E

    1993-01-01

    OBJECTIVE--To study the effect of periconceptional multivitamin supplementation on neural tube defects and other congenital abnormality entities. DESIGN--Randomised controlled trial of supplementation with multivitamins and trace elements. SETTING--Hungarian family planning programme. SUBJECTS--4156 pregnancies with known outcome and 3713 infants evaluated in the eighth month of life. INTERVENTIONS--A single tablet of a multivitamin including 0.8 mg of folic acid or trace elements supplement daily for at least one month before conception and at least two months after conception. MAIN OUTCOME MEASURES--Number of major and mild congenital abnormalities. RESULTS--The rate of all major congenital abnormalities was significantly lower in the group given vitamins than in the group given trace elements and this difference cannot be explained totally by the significant reduction of neural tube defects. The rate of major congenital abnormalities other than neural tube defects and genetic syndromes was 9.0/1000 in pregnancies with known outcome in the vitamin group and 16.6/1000 in the trace element group; relative risk 1.85 (95% confidence interval 1.02 to 3.38); difference, 7.6/1000. The rate of all major congenital abnormalities other than neural tube defects and genetic syndromes diagnosed up to the eighth month of life was 14.7/1000 informative pregnancies in the vitamin group and 28.3/1000 in the trace element group; relative risk 1.95 (1.23 to 3.09); difference, 13.6/1000. The rate of some congenital abnormalities was lower in the vitamin group than in the trace element group but the differences for each group of abnormalities were not significant. CONCLUSIONS--Periconceptional multivitamin supplementation can reduce not only the rate of neural tube defects but also the rate of other major non-genetic syndromatic congenital abnormalities. Further studies are needed to differentiate the chance effect and vitamin dependent effect. PMID:8324432

  1. Coptis chinensis Polysaccharides Inhibit Advanced Glycation End Product Formation.

    PubMed

    Yang, Ye; Li, Yun; Yin, Dengke; Chen, Song; Gao, Xiangdong

    2016-06-01

    Coptis chinensis Franch (Huanglian) is commonly used to treat diabetes in China. In this study, the effects of the C. chinensis Franch polysaccharides (CCP) on advanced glycation end product (AGE) formation in vitro and in streptozotocin-induced diabetic mice were investigated. CCP significantly inhibited all the three periods of nonenzymatic protein glycation in vitro, including Amadori product, dicarbonyl compound, and AGE formation (P < .01). In diabetic mice, the administration of CCP not only improved both bodyweight and serum insulin and decreased fasting blood glucose and glycated serum protein concentrations but also decreased the AGE accumulations and morphological abnormalities in pancreas and liver. The inhibitory effects of CCP on AGE formation afford a potential therapeutic use in the prevention and treatment of diabetes.

  2. Retinal abnormalities in β-thalassemia major

    PubMed Central

    Bhoiwala, Devang L.; Dunaief, Joshua L.

    2015-01-01

    Patients with beta (β)-thalassemia (β-TM: thalassemia major, β-TI: thalassemia intermedia) have a variety of complications that may affect all organs, including the eye. Ocular abnormalities include retinal pigment epithelium degeneration, angioid streaks, venous tortuosity, night blindness, visual field defects, decreased visual acuity, color vision abnormalities, and acute visual loss. Patients with β-TM are transfusion dependent and require iron chelation therapy (ICT) in order to survive. Retinal degeneration may result from either retinal iron accumulation from transfusion-induced iron overload or retinal toxicity induced by ICT. Some who were never treated with ICT exhibited retinopathy, and others receiving ICT had chelator-induced retinopathy. We will focus on retinal abnormalities present in individuals with β-TM viewed in light of new findings on the mechanisms and manifestations of retinal iron toxicity. PMID:26325202

  3. Neurological abnormalities associated with CDMA exposure.

    PubMed

    Hocking, B; Westerman, R

    2001-09-01

    Dysaesthesiae of the scalp and neurological abnormality after mobile phone use have been reported previously, but the roles of the phone per se or the radiations in causing these findings have been questioned. We report finding a neurological abnormality in a patient after accidental exposure of the left side of the face to mobile phone radiation [code division multiple access (CDMA)] from a down-powered mobile phone base station antenna. He had headaches, unilateral left blurred vision and pupil constriction, unilateral altered sensation on the forehead, and abnormalities of current perception thresholds on testing the left trigeminal ophthalmic nerve. His nerve function recovered during 6 months follow-up. His exposure was 0.015-0.06 mW/cm(2) over 1-2 h. The implications regarding health effects of radiofrequency radiation are discussed.

  4. Sleep Physiology, Abnormal States, and Therapeutic Interventions

    PubMed Central

    Wickboldt, Alvah T.; Bowen, Alex F.; Kaye, Aaron J.; Kaye, Adam M.; Rivera Bueno, Franklin; Kaye, Alan D.

    2012-01-01

    Sleep is essential. Unfortunately, a significant portion of the population experiences altered sleep states that often result in a multitude of health-related issues. The regulation of sleep and sleep-wake cycles is an area of intense research, and many options for treatment are available. The following review summarizes the current understanding of normal and abnormal sleep-related conditions and the available treatment options. All clinicians managing patients must recommend appropriate therapeutic interventions for abnormal sleep states. Clinicians' solid understanding of sleep physiology, abnormal sleep states, and treatments will greatly benefit patients regardless of their disease process. PMID:22778676

  5. [Liver enzyme abnormalities among oil refinery workers].

    PubMed

    Carvalho, Fernando Martins; Silvany Neto, Annibal Muniz; Mendes, João Luiz Barberino; Cotrim, Helma Pinchemel; Nascimento, Ana Lísia Cunha; Lima Júnior, Alberto Soares; Cunha, Tatiana Oliveira Bernardo da

    2006-02-01

    Occupational exposure typical of an oil refinery may alter liver function among the workers. Thus, the objective of the study was to identify risk factors for liver enzyme abnormalities among oil refinery workers. The workers at an oil refinery in Northeastern Brazil underwent routine annual medical examination from 1982 to 1998. This case-control study investigated all the 150 cases of individuals with simultaneous gamma-glutamyltransferase and alanine aminotransferase abnormalities of at least 10% above reference levels. As controls, 150 workers without any liver enzyme or bilirubin abnormalities since starting to work there were selected. Odds ratios and the respective 95% confidence intervals were calculated from logistic regression models. In all the production sectors, the risk of liver enzyme abnormalities was significantly higher than in the administrative sector (OR=5.7; 95% CI: 1.7-18.4), even when the effects of alcohol, obesity and medical history of hepatitis were controlled for. During the period from 1992 to 1994, 88 out of the 89 cases occurred among workers from the various production sectors. Occupational exposure plays an important role in causing liver enzyme abnormalities among oil refinery workers. This is in addition to the specifically biological and/or behavioral risk factors such as obesity and alcohol consumption.

  6. The prevalence of chromosomal abnormalities in subgroups of infertile men.

    PubMed

    Dul, E C; Groen, H; van Ravenswaaij-Arts, C M A; Dijkhuizen, T; van Echten-Arends, J; Land, J A

    2012-01-01

    The prevalence of chromosomal abnormalities is assumed to be higher in infertile men and inversely correlated with sperm concentration. Although guidelines advise karyotyping infertile men, karyotyping is costly, therefore it would be of benefit to identify men with the highest risk of chromosomal abnormalities, possibly by using parameters other than sperm concentration. The aim of this study was to evaluate several clinical parameters in azoospermic and non-azoospermic men, in order to assess the prevalence of chromosomal abnormalities in different subgroups of infertile men. In a retrospective cohort of 1223 azoospermic men and men eligible for ICSI treatment, we studied sperm parameters, hormone levels and medical history for an association with chromosomal abnormalities. The prevalence of chromosomal abnormalities in the cohort was 3.1%. No association was found between chromosomal abnormalities and sperm volume, concentration, progressive motility or total motile sperm count. Azoospermia was significantly associated with the presence of a chromosomal abnormality [15.2%, odds ratio (OR) 7.70, P < 0.001]. High gonadotrophin levels were also associated with an increased prevalence of chromosomal abnormalities (OR 2.96, P = 0.013). Azoospermic men with a positive andrologic history had a lower prevalence of chromosomal abnormalities than azoospermic men with an uneventful history (OR 0.28, P = 0.047). In non-azoospermic men, we found that none of the studied variables were associated with the prevalence of chromosomal abnormalities. We show that the highest prevalence of chromosomal abnormalities is found in hypergonadotrophic azoospermic men with an uneventful andrologic history.

  7. Abnormal/Emergency Situations. Impact of Unmanned Aircraft Systems Emergency and Abnormal Events on the National Airspace System

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Access 5 analyzed the differences between UAS and manned aircraft operations under five categories of abnormal or emergency situations: Link Failure, Lost Communications, Onboard System Failures, Control Station Failures and Abnormal Weather. These analyses were made from the vantage point of the impact that these operations have on the US air traffic control system, with recommendations for new policies and procedures included where appropriate.

  8. Radio frequency abnormal dielectric response of manganese chromite (MnCr{sub 2}O{sub 4}) nanoparticles synthesized by coprecipitation method

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

    Gul, Muhammad, E-mail: mgul@upesh.edu.pk

    2016-04-15

    Highlights: • Uniform MnCr{sub 2}O{sub 4} nanoparticles synthesized by surfactant-free coprecipitation route. • XRD analysis confirmed the single spinel phase formation in the material. • Dielectric loss was found abnormal over certain lower frequencies. • AC conductivity proved the involvement of small polarons in conduction process. - Abstract: Radio frequency dielectric behavior of nanocrystalline MnCr{sub 2}O{sub 4} synthesized via surfactant-free controlled coprecipitation route has been studied. Keeping in view the necessity of particle size uniformity and phase purity for genuine performance, experimental conditions were optimized accordingly. The scanning electron micrographs of the synthesized product revealed the formation of monodispersed particlemore » system. X-ray diffraction analysis confirmed monophasic spinel structure formation with 65 nm crystallite size. Two characteristic peaks observed between 700 cm{sup −1} and 400 cm{sup −1} in the FTIR spectrum also supported the spinel phase purity of compound. The dielectric constant was found normal, but loss tangent of the sample showed abnormal behavior with frequency. The observed dielectric behavior of the synthesized product has been explained on the basis of space-charge polarization according to Maxwell–Wagner’s model and mutual contribution of n-type &p-type charge carriers (Rezlescu model). The ac conductivity linearly increased with frequency highlighting the existence of polaron hopping.« less

  9. "Jeopardy" in Abnormal Psychology.

    ERIC Educational Resources Information Center

    Keutzer, Carolin S.

    1993-01-01

    Describes the use of the board game, Jeopardy, in a college level abnormal psychology course. Finds increased student interaction and improved application of information. Reports generally favorable student evaluation of the technique. (CFR)

  10. 21 CFR 864.7415 - Abnormal hemoglobin assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Abnormal hemoglobin assay. 864.7415 Section 864... hemoglobin assay. (a) Identification. An abnormal hemoglobin assay is a device consisting of the reagents... hemoglobin types. (b) Classification. Class II (performance standards). [45 FR 60618, Sept. 12, 1980] ...

  11. 21 CFR 864.7415 - Abnormal hemoglobin assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Abnormal hemoglobin assay. 864.7415 Section 864... hemoglobin assay. (a) Identification. An abnormal hemoglobin assay is a device consisting of the reagents... hemoglobin types. (b) Classification. Class II (performance standards). [45 FR 60618, Sept. 12, 1980] ...

  12. 21 CFR 864.7415 - Abnormal hemoglobin assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Abnormal hemoglobin assay. 864.7415 Section 864.7415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7415 Abnormal...

  13. 21 CFR 864.7415 - Abnormal hemoglobin assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Abnormal hemoglobin assay. 864.7415 Section 864.7415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7415 Abnormal...

  14. 21 CFR 864.7415 - Abnormal hemoglobin assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Abnormal hemoglobin assay. 864.7415 Section 864.7415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7415 Abnormal...

  15. Abnormal carbene-silicon halide complexes.

    PubMed

    Wang, Yuzhong; Xie, Yaoming; Wei, Pingrong; Schaefer, Henry F; Robinson, Gregory H

    2016-04-14

    Reaction of the anionic N-heterocyclic dicarbene (NHDC), [:C{[N(2,6-Pr(i)2C6H3)]2CHCLi}]n (1), with SiCl4 gives the trichlorosilyl-substituted (at the C4 carbon) N-heterocyclic carbene complex (7). Abnormal carbene-SiCl4 complex (8) may be conveniently synthesized by combining 7 with HCl·NEt3. In addition, 7 may react with CH2Cl2 in warm hexane, giving the abnormal carbene-complexed SiCl3(+) cation (9). The nature of the bonding in 9 was probed with complementary DFT computations.

  16. Qualitative metabolomics profiling of serum and bile from dogs with gallbladder mucocele formation

    PubMed Central

    Mathews, Kyle G.; Cullen, John; Seiler, Gabriela

    2018-01-01

    Mucocele formation is characterized by secretion of abnormally thick mucus by the gallbladder epithelium of dogs that may cause obstruction of the bile duct or rupture of the gallbladder. The disease is increasingly recognized and is associated with a high morbidity and mortality. The cause of gallbladder mucocele formation in dogs is unknown. There is a strong breed predisposition and affected dogs have a high incidence of concurrent endocrinopathy or hyperlipidemia. These observations suggest a significant influence of both genetic and metabolic factors on disease pathogenesis. In this study, we investigated a theory that mucocele formation is associated with a syndrome of metabolic disruption. We surmised that a global, untargeted metabolomics approach could provide unique insight into the systemic pathogenesis of gallbladder mucocele formation and identify specific compounds as candidate biomarkers or treatment targets. Moreover, concurrent examination of the serum and hepatic duct bile metabolome would enable the construction of mechanism-based theories or identification of specific compounds responsible for altered function of the gallbladder epithelium. Abnormalities observed in dogs with gallbladder mucocele formation, including a 33-fold decrease in serum adenosine 5’-monophosphate (AMP), lower quantities of precursors required for synthesis of energy transporting nucleotides, and increases in citric acid cycle intermediates, suggest excess metabolic energy and a carbon surplus. Altered quantities of compounds involved in protein translation and RNA turnover, together with accumulation of gamma-glutamylated and N-acetylated amino acids in serum suggest abnormal regulation of protein and amino acid metabolism. Increases in lathosterol and 7α-hydroxycholesterol suggest a primary increase in cholesterol synthesis and diversion to bile acid formation. A number of specific biomarker compounds were identified for their ability to distinguish between control

  17. Diverticular Disease of the Colon: Neuromuscular Function Abnormalities.

    PubMed

    Bassotti, Gabrio; Villanacci, Vincenzo; Bernardini, Nunzia; Dore, Maria P

    2016-10-01

    Colonic diverticular disease is a frequent finding in daily clinical practice. However, its pathophysiological mechanisms are largely unknown. This condition is likely the result of several concomitant factors occurring together to cause anatomic and functional abnormalities, leading as a result to the outpouching of the colonic mucosa. A pivotal role seems to be played by an abnormal colonic neuromuscular function, as shown repeatedly in these patients, and by an altered visceral perception. There is recent evidence that these abnormalities might be related to the derangement of the enteric innervation, to an abnormal distribution of mucosal neuropeptides, and to low-grade mucosal inflammation. The latter might be responsible for the development of visceral hypersensitivity, often causing abdominal pain in a subset of these patients.

  18. Abnormal Uterine Bleeding.

    PubMed

    Benetti-Pinto, Cristina Laguna; Rosa-E-Silva, Ana Carolina Japur de Sá; Yela, Daniela Angerame; Soares Júnior, José Maria

    2017-07-01

    Abnormal uterine bleeding is a frequent condition in Gynecology. It may impact physical, emotional sexual and professional aspects of the lives of women, impairing their quality of life. In cases of acute and severe bleeding, women may need urgent treatment with volumetric replacement and prescription of hemostatic substances. In some specific cases with more intense and prolonged bleeding, surgical treatment may be necessary. The objective of this chapter is to describe the main evidence on the treatment of women with abnormal uterine bleeding, both acute and chronic. Didactically, the treatment options were based on the current International Federation of Gynecology and Obstetrics (FIGO) classification system (PALM-COEIN). The etiologies of PALM-COEIN are: uterine Polyp (P), Adenomyosis (A), Leiomyoma (L), precursor and Malignant lesions of the uterine body (M), Coagulopathies (C), Ovulatory dysfunction (O), Endometrial dysfunction (E), Iatrogenic (I), and Not yet classified (N). The articles were selected according to the recommendation grades of the PubMed, Cochrane and Embase databases, and those in which the main objective was the reduction of uterine menstrual bleeding were included. Only studies written in English were included. All editorial or complete papers that were not consistent with abnormal uterine bleeding, or studies in animal models, were excluded. The main objective of the treatment is the reduction of menstrual flow and morbidity and the improvement of quality of life. It is important to emphasize that the treatment in the acute phase aims to hemodynamically stabilize the patient and stop excessive bleeding, while the treatment in the chronic phase is based on correcting menstrual dysfunction according to its etiology and clinical manifestations. The treatment may be surgical or pharmacological, and the latter is based mainly on hormonal therapy, anti-inflammatory drugs and antifibrinolytics. Thieme Revinter Publicações Ltda Rio de Janeiro

  19. Abnormal global and local event detection in compressive sensing domain

    NASA Astrophysics Data System (ADS)

    Wang, Tian; Qiao, Meina; Chen, Jie; Wang, Chuanyun; Zhang, Wenjia; Snoussi, Hichem

    2018-05-01

    Abnormal event detection, also known as anomaly detection, is one challenging task in security video surveillance. It is important to develop effective and robust movement representation models for global and local abnormal event detection to fight against factors such as occlusion and illumination change. In this paper, a new algorithm is proposed. It can locate the abnormal events on one frame, and detect the global abnormal frame. The proposed algorithm employs a sparse measurement matrix designed to represent the movement feature based on optical flow efficiently. Then, the abnormal detection mission is constructed as a one-class classification task via merely learning from the training normal samples. Experiments demonstrate that our algorithm performs well on the benchmark abnormal detection datasets against state-of-the-art methods.

  20. Sensitive determination of chlorogenic acid in pharmaceutical products based on the decoration of 3D macroporous carbon with Au nanoparticles via polyoxometalates.

    PubMed

    Zhang, Tongrui; Liu, Mengjun; Zhang, Qianqian; Wang, Yeyu; Kong, Xiangyi; Wang, Lei; Wang, Huan; Zhang, Yufan

    2017-07-10

    A simple and sensitive electrochemical sensor is constructed for the detection of chlorogenic acid (CGA) based on Au nanoparticles (NPs)/polyoxometalates/3D macroporous carbon (Au-POMs-MPC). Serving as both a reducing and stabilizing agent, the Keggin-type POM, H 3 PW 12 O 40 , is used for the synthesis of stable colloidal Au NPs and then used to link them to MPC at a mild temperature. Because of the unique structural properties and synergetic catalytic effect, Au-POMs-MPC can be developed as an effective sensing platform for the detection of CGA, which showed high activity and excellent analytical performance towards CGA, such as a wide linear range of 2.28 nM-3.24 μM, a high sensitivity of 30 554.71 μA mM -1 , and a low limit of detection of 2.15 nM. Importantly, the successfully fabricated Au-POMs-MPC device accurately measured the amount of CGA in pharmaceutical samples.

  1. Three-dimensionally ordered macroporous Li2FeSiO4/C composite as a high performance cathode for advanced lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Ding, Zhengping; Liu, Jiatu; Ji, Ran; Zeng, Xiaohui; Yang, Shuanglei; Pan, Anqiang; Ivey, Douglas G.; Wei, Weifeng

    2016-10-01

    Li2MSiO4 (M = Mn, Fe, Co, Ni, et al.) has received great attention because of the theoretical possibility to reversibly deintercalate two Li+ ions from the structure. However, the silicates still suffer from low electronic conductivity, sluggish lithium ion diffusion and structural instability upon deep cycling. In order to solve these problems, a "hard-soft" templating method has been developed to synthesize three-dimensionally ordered macroporous (3DOM) Li2FeSiO4/C composites. The 3DOM Li2FeSiO4/C composites show a high reversible capacity (239 mAh g-1) with ∼1.50 lithium ion insertion/extraction, a capacity retention of nearly 100% after 420 cycles and excellent rate capability. The enhanced electrochemical performance is ascribed to the interconnected carbon framework that improves the electronic conductivity and the 3DOM structure that offers short Li ion diffusion pathways and restrains volumetric changes.

  2. Abnormal Magnetic Field Effects on Electrogenerated Chemiluminescence

    NASA Astrophysics Data System (ADS)

    Pan, Haiping; Shen, Yan; Wang, Hongfeng; He, Lei; Hu, Bin

    2015-03-01

    We report abnormal magnetic field effects on electrogenerated chemiluminescence (MFEECL) based on triplet emission from the Ru(bpy)3Cl2-TPrA electrochemical system: the appearance of MFEECL after magnetic field ceases. In early studies the normal MFEECL have been observed from electrochemical systems during the application of magnetic field. Here, the abnormal MFEECL suggest that the activated charge-transfer [Ru(bpy)33+ … TPrA•] complexes may become magnetized in magnetic field and experience a long magnetic relaxation after removing magnetic field. Our analysis indicates that the magnetic relaxation can gradually increase the density of charge-transfer complexes within reaction region due to decayed magnetic interactions, leading to a positive component in the abnormal MFEECL. On the other hand, the magnetic relaxation facilitates an inverse conversion from triplets to singlets within charge-transfer complexes. The inverse triplet --> singlet conversion reduces the density of triplet light-emitting states through charge-transfer complexes and gives rise to a negative component in the abnormal MFEECL. The combination of positive and negative components can essentially lead to a non-monotonic profile in the abnormal MFEECL after ceasing magnetic field. Nevertheless, our experimental studies may reveal un-usual magnetic behaviors with long magnetic relaxation from the activated charge-transfer [Ru(bpy)33+ … TPrA•] complexes in solution at room temperature.

  3. Salivary glands abnormalities in oculo-auriculo-vertebral spectrum.

    PubMed

    Brotto, Davide; Manara, Renzo; Vio, Stefania; Ghiselli, Sara; Cantone, Elena; Mardari, Rodica; Toldo, Irene; Stritoni, Valentina; Castiglione, Alessandro; Lovo, Elisa; Trevisi, Patrizia; Bovo, Roberto; Martini, Alessandro

    2018-01-01

    Feeding and swallowing impairment are present in up to 80% of oculo-auriculo-vertebral spectrum (OAVS) patients. Salivary gland abnormalities have been reported in OAVS patients but their rate, features, and relationship with phenotype severity have yet to be defined. Parotid and submandibular salivary gland hypo/aplasia was evaluated on head MRI of 25 OAVS patients (16 with severe phenotype, Goldenhar syndrome) and 11 controls. All controls disclosed normal salivary glands. Abnormal parotid glands were found exclusively ipsilateral to facial microsomia in 21/25 OAVS patients (84%, aplasia in six patients) and showed no association with phenotype severity (14/16 patients with Goldenhar phenotype vs 7/9 patients with milder phenotype, p = 0.6). Submandibular salivary gland hypoplasia was detected in six OAVS patients, all with concomitant ipsilateral severe involvement of the parotid gland (p < 0.001). Submandibular salivary gland hypoplasia was associated to Goldenhar phenotype (p < 0.05). Parotid gland abnormalities were associated with ipsilateral fifth (p < 0.001) and seventh cranial nerve (p = 0.001) abnormalities. No association was found between parotid gland anomaly and ipsilateral internal carotid artery, inner ear, brain, eye, or spine abnormalities (p > 0.6). Salivary gland abnormalities are strikingly common in OAVS. Their detection might help the management of OAVS-associated swallowing and feeding impairment.

  4. Detection of Structural Abnormalities Using Neural Nets

    NASA Technical Reports Server (NTRS)

    Zak, M.; Maccalla, A.; Daggumati, V.; Gulati, S.; Toomarian, N.

    1996-01-01

    This paper describes a feed-forward neural net approach for detection of abnormal system behavior based upon sensor data analyses. A new dynamical invariant representing structural parameters of the system is introduced in such a way that any structural abnormalities in the system behavior are detected from the corresponding changes to the invariant.

  5. An Abnormal Psychology Community Based Interview Assignment

    ERIC Educational Resources Information Center

    White, Geoffry D.

    1977-01-01

    A course option in abnormal psychology involves students in interviewing and observing the activities of individuals in the off-campus community who are concerned with some aspect of abnormal psychology. The technique generates student interest in the field when they interview people about topics such as drug abuse, transsexualism, and abuse of…

  6. Incidence of abnormal liver biochemical tests in hyperthyroidism.

    PubMed

    Lin, Tiffany Y; Shekar, Anshula O; Li, Ning; Yeh, Michael W; Saab, Sammy; Wilson, Mark; Leung, Angela M

    2017-05-01

    Abnormal serum liver function tests are common in patients with untreated thyrotoxicosis, even prior to the initiation of antithyroidal medications that may worsen the severity of the abnormal serum liver biochemistries. There is a wide range of the incidence of these abnormalities in the published literature. The aim of this study was to assess the risks factors and threshold of thyrotoxicosis severity for developing an abnormal liver biochemical test upon the diagnosis of new thyrotoxicosis. Single-institution retrospective cohort study. Patients of ≥18 years old receiving medical care at a large, academic, urban US medical centre between 2002-2016. Inclusion criteria were a serum thyroid stimulating hormone (TSH) concentration of <0·3 mIU/l or ICD-9 code for thyrotoxicosis, with thyrotoxicosis confirmed by either a concurrent elevated serum triiodothyronine (T3) or thyroxine (T4) concentration ([total or free] within 3 months), and an available liver biochemical test(s) within 6 months of thyrotoxicosis. The biochemical liver tests assessed were serum aspartate transaminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), gamma-glutamyltransferase (GGT), total bilirubin, and conjugated bilirubin concentrations. In this cohort of 1514 subjects, the overall incidence of any biochemical liver test abnormality within 6 months of thyrotoxicosis was 39%. An initial serum TSH concentration <0·02 mIU/l, male gender, and African-American race were significant predictors of an abnormal serum liver biochemical test within 6 months of the diagnosis of new-onset untreated thyrotoxicosis. This study identifies risk factors for patients who develop an abnormal serum liver biochemical test result within 6 months of a diagnosis of untreated thyrotoxicosis. © 2017 John Wiley & Sons Ltd.

  7. Intelligent Process Abnormal Patterns Recognition and Diagnosis Based on Fuzzy Logic.

    PubMed

    Hou, Shi-Wang; Feng, Shunxiao; Wang, Hui

    2016-01-01

    Locating the assignable causes by use of the abnormal patterns of control chart is a widely used technology for manufacturing quality control. If there are uncertainties about the occurrence degree of abnormal patterns, the diagnosis process is impossible to be carried out. Considering four common abnormal control chart patterns, this paper proposed a characteristic numbers based recognition method point by point to quantify the occurrence degree of abnormal patterns under uncertain conditions and a fuzzy inference system based on fuzzy logic to calculate the contribution degree of assignable causes with fuzzy abnormal patterns. Application case results show that the proposed approach can give a ranked causes list under fuzzy control chart abnormal patterns and support the abnormity eliminating.

  8. Gestational lead exposure induces developmental abnormalities and up-regulates apoptosis of fetal cerebellar cells in rats.

    PubMed

    Mousa, Alyaa M; Al-Fadhli, Ameera S; Rao, Muddanna S; Kilarkaje, Narayana

    2015-01-01

    Lead (Pb), a known environmental toxicant, adversely affects almost all organ systems. In this study, we investigated the effects of maternal lead exposure on fetal rat cerebellum. Female Sprague-Dawley rats were given lead nitrate in drinking water (0, 0.5, and 1%) for two weeks before conception, and during pregnancy. Fetuses were collected by caesarian section on gestational day 21 and observed for developmental abnormalities. The fetal cerebellar sections from control and 1% lead group were stained with cresyl violet. Immunohistochemical expressions of p53, Bax, Bcl-2, and caspase 3 were quantified by AnalySIS image analyzer (Life Science, Germany). Lead exposure induced developmental abnormalities of eyes, ear, limbs, neck and ventral abdominal wall; however, these abnormalities were commonly seen in the 1% lead-treated group. In addition, lead also caused fetal mortality and reduced body growth in both dose groups and reduced brain weight in the 1% lead-treated group. The fetal cerebella from the 1% lead-treated group showed unorganized cerebellar cortical layers, and degenerative changes in granule and Purkinje cells such as the formation of clumps of Nissl granules. An increase in Bax and caspase 3, and a decrease in Bcl-2 (p < 0.05), but not in p53, showed apoptosis of the neurons. In conclusion, gestational lead exposure in rats induces fetal toxicity and developmental abnormalities. The lead exposure also impairs development of cerebellar layers, induces structural changes, and apoptosis in the fetal cerebellar cortex. These results suggest that lead exposure during gestation is extremely toxic to developing cerebellum in rats.

  9. Enrichment of antioxidants in black garlic juice using macroporous resins and their protective effects on oxidation-damaged human erythrocytes.

    PubMed

    Zou, Ying; Zhao, Mouming; Yang, Kun; Lin, Lianzhu; Wang, Yong

    2017-08-15

    The black garlic juice is popular for its nutritive value. Enrichment of antioxidants is needed to make black garlic extract an effective functional ingredient. Five macroporous resins were evaluated for their capacity in adsorbing antioxidants in black garlic juice. XAD-16 resin was chosen for further study due to its high adsorption and desorption ratios. Pseudo-second-order kinetics (q e =625μmol Trolox equiv/g dry resin, k 2 =0.0001463) and Freundlich isotherm models (ΔH=-10.1547kJ/mol) were suitable for describing the whole exothermic and physical adsorption processes of the antioxidants from black garlic juice on XAD-16 resin. The antioxidants and phenolics were mostly enriched in 40% ethanol fraction by XAD-16 resin column chromatography. The black garlic extract and its fractions could protect erythrocytes against AAPH-induced hemolysis in dose-dependent manners. The pretreatment of AAPH-damaged erythrocytes with 40% ethanol fractions (2.5mg/mL) significantly decreased the hemolysis ratios from 53.58% to 3.79%. The 40% ethanol fraction possessing strong intracellular antioxidant activity could be used as a functional food ingredient. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Acute Ketamine Administration Corrects Abnormal Inflammatory Bone Markers in Major Depressive Disorder

    PubMed Central

    Kadriu, Bashkim; Gold, Philip W; Luckenbaugh, David A; Lener, Marc S; Ballard, Elizabeth D; Niciu, Mark J; Henter, Ioline D; Park, Lawrence T; De Sousa, Rafael Teixeira; Yuan, Peixiong; Machado-Vieira, Rodrigo; Zarate, Carlos A

    2017-01-01

    Patients with major depressive disorder (MDD) have clinically relevant, significant decreases in bone mineral density (BMD). We sought to determine if predictive markers of bone inflammation—the osteoprotegerin (OPG)-RANK-RANKL system or osteopontin (OPN)—play a role in the bone abnormalities associated with MDD and, if so, whether ketamine treatment corrected the abnormalities. The OPG-RANK-RANKL system plays the principal role in determining the balance between bone resorption and bone formation. RANKL is the osteoclast differentiating factor and diminishes BMD. OPG is a decoy receptor for RANKL, thereby increasing BMD. OPN is the bone glue that acts as a scaffold between bone tissues matrix composition to bind them together and is an important component of bone strength and fracture resistance. Twenty-eight medication-free inpatients with treatment-resistant MDD and 16 healthy controls (HCs) participated in the study. Peripheral bone marker levels and their responses to IV ketamine infusion in MDD patients and HCs were measured at four time points: at baseline, and post-infusion at 230 minutes, Day 1, and Day 3. Patients with MDD had significant decreases in baseline OPG/RANKL ratio and in plasma OPN levels. Ketamine significantly increased both the OPG/RANKL ratio and plasma OPN levels and significantly decreased RANKL levels. Bone marker levels in HCs remained unaltered. We conclude that the OPG-RANK-RANKL system and the OPN system play important roles in the serious bone abnormalities associated with MDD. These data suggest that in addition to its antidepressant effects, ketamine also has a salutary effect on a major medical complication of depressive illness. PMID:28555075

  11. Acute ketamine administration corrects abnormal inflammatory bone markers in major depressive disorder.

    PubMed

    Kadriu, B; Gold, P W; Luckenbaugh, D A; Lener, M S; Ballard, E D; Niciu, M J; Henter, I D; Park, L T; De Sousa, R T; Yuan, P; Machado-Vieira, R; Zarate, C A

    2017-05-30

    Patients with major depressive disorder (MDD) have clinically relevant, significant decreases in bone mineral density (BMD). We sought to determine if predictive markers of bone inflammation-the osteoprotegerin (OPG)-RANK-RANKL system or osteopontin (OPN)-play a role in the bone abnormalities associated with MDD and, if so, whether ketamine treatment corrected the abnormalities. The OPG-RANK-RANKL system plays the principal role in determining the balance between bone resorption and bone formation. RANKL is the osteoclast differentiating factor and diminishes BMD. OPG is a decoy receptor for RANKL, thereby increasing BMD. OPN is the bone glue that acts as a scaffold between bone tissues matrix composition to bind them together and is an important component of bone strength and fracture resistance. Twenty-eight medication-free inpatients with treatment-resistant MDD and 16 healthy controls (HCs) participated in the study. Peripheral bone marker levels and their responses to IV ketamine infusion in MDD patients and HCs were measured at four time points: at baseline, and post-infusion at 230 min, Day 1, and Day 3. Patients with MDD had significant decreases in baseline OPG/RANKL ratio and in plasma OPN levels. Ketamine significantly increased both the OPG/RANKL ratio and plasma OPN levels, and significantly decreased RANKL levels. Bone marker levels in HCs remained unaltered. We conclude that the OPG-RANK-RANKL system and the OPN system play important roles in the serious bone abnormalities associated with MDD. These data suggest that, in addition to its antidepressant effects, ketamine also has a salutary effect on a major medical complication of depressive illness.Molecular Psychiatry advance online publication, 30 May 2017; doi:10.1038/mp.2017.109.

  12. Encapsulation of mesenchymal stem cells in chitosan/β-glycerophosphate hydrogel for seeding on a novel calcium phosphate cement scaffold.

    PubMed

    Liu, Tao; Li, Jian; Shao, Zengwu; Ma, Kaige; Zhang, Zhicai; Wang, Baichuan; Zhang, Yannan

    2018-06-01

    Due to its moldability, biocompatibility, osteoconductivity and resorbability, calcium phosphate cement (CPC) is a highly promising scaffold material for orthopedic applications. However, pH changes and ionic activity during the CPC setting reaction may adversely affect cells seeded directly on CPC. Moreover, a lack of macropores in CPC limits ingrowth of new bone. The objectives of this study were to prepare macroporous CPC scaffolds via porogen leaching, using mannitol crystals as the porogen and to evaluate the in vitro proliferation and osteogenic differentiation of mesenchymal stem cells (MSCs) encapsulated in chitosan/β-glycerophosphate (C/GP) hydrogel prior to exposure to the novel CPC scaffold. MSCs were found to be adhered to the surfaces of CPC macropores via scanning electron microscopy. The viability and osteogenic differentiation of MSCs in C/GP hydrogel with or without exposure to CPC constructs containing mannitol crystals indicated that coating with C/GP hydrogel protected the cells during cement mixing and setting. In conclusion, novel, macroporous CPC scaffolds were prepared, and our data indicate that a hydrogel encapsulation-based strategy can be used to protect cells during scaffold formation. Thus, the MSC-laden CPC scaffolds show promise for the delivery of stem cells to promote bone regeneration. Copyright © 2018 IPEM. Published by Elsevier Ltd. All rights reserved.

  13. [Normal and abnormal skin color].

    PubMed

    Ortonne, J-P

    2012-11-01

    The varieties of normal skin color in humans range from people of "no color" (pale white) to "people of color" (light brown, dark brown, and black). Skin color is a blend resulting from the skin chromophores red (oxyhaemoglobin), blue (deoxygenated haemoglobin), yellow-orange (carotene, an exogenous pigment), and brown (melanin). Melanin, however, is the major component of skin color ; it is the presence or absence of melanin in the melanosomes in melanocytes and melanin in keratinocytes that is responsible for epidermal pigmentation, and the presence of melanin in macrophages or melanocytes in the dermis that is responsible for dermal pigmentation. Two groups of pigmentary disorders are commonly distinguished: the disorders of the quantitative and qualitative distribution of normal pigment and the abnormal presence of exogenous or endogenous pigments in the skin. The first group includes hyperpigmentations, which clinically manifest by darkening of the skin color, and leukodermia, which is characterized by lightening of the skin. Hypermelanosis corresponds to an overload of melanin or an abnormal distribution of melanin in the skin. Depending on the color, melanodermia (brown/black) and ceruloderma (blue/grey) are distinguished. Melanodermia correspond to epidermal hypermelanocytosis (an increased number of melanocytes) or epidermal hypermelanosis (an increase in the quantity of melanin in the epidermis with no modification of the number of melanocytes). Ceruloderma correspond to dermal hypermelanocytosis (abnormal presence in the dermis of cells synthesizing melanins) ; leakage in the dermis of epidermal melanin also exists, a form of dermal hypermelanosis called pigmentary incontinence. Finally, dyschromia can be related to the abnormal presence in the skin of a pigment of exogenous or endogenous origin. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  14. Hemostatic abnormalities in Noonan syndrome.

    PubMed

    Artoni, Andrea; Selicorni, Angelo; Passamonti, Serena M; Lecchi, Anna; Bucciarelli, Paolo; Cerutti, Marta; Cianci, Paola; Gianniello, Francesca; Martinelli, Ida

    2014-05-01

    A bleeding diathesis is a common feature of Noonan syndrome, and various coagulation abnormalities have been reported. Platelet function has never been carefully investigated. The degree of bleeding diathesis in a cohort of patients with Noonan syndrome was evaluated by a validated bleeding score and investigated with coagulation and platelet function tests. If ratios of prothrombin time and/or activated partial thromboplastin time were prolonged, the activity of clotting factors was measured. Individuals with no history of bleeding formed the control group. The study population included 39 patients and 28 controls. Bleeding score was ≥2 (ie, suggestive of a moderate bleeding diathesis) in 15 patients (38.5%) and ≥4 (ie, suggestive of a severe bleeding diathesis) in 7 (17.9%). Abnormal coagulation and/or platelet function tests were found in 14 patients with bleeding score ≥2 (93.3%) but also in 21 (87.5%) of those with bleeding score <2. The prothrombin time and activated partial thromboplastin time were prolonged in 18 patients (46%) and partial deficiency of factor VII, alone or in combination with the deficiency of other vitamin K-dependent factors, was the most frequent coagulation abnormality. Moreover, platelet aggregation and secretion were reduced in 29 of 35 patients (82.9%, P < .01 for all aggregating agents). Nearly 40% of patients with the Noonan syndrome had a bleeding diathesis and >90% of them had platelet function and/or coagulation abnormalities. Results of these tests should be taken into account in the management of bleeding or invasive procedures in these patients. Copyright © 2014 by the American Academy of Pediatrics.

  15. Retinal abnormalities in β-thalassemia major.

    PubMed

    Bhoiwala, Devang L; Dunaief, Joshua L

    2016-01-01

    Patients with beta (β)-thalassemia (β-TM: β-thalassemia major, β-TI: β-thalassemia intermedia) have a variety of complications that may affect all organs, including the eye. Ocular abnormalities include retinal pigment epithelial degeneration, angioid streaks, venous tortuosity, night blindness, visual field defects, decreased visual acuity, color vision abnormalities, and acute visual loss. Patients with β-thalassemia major are transfusion dependent and require iron chelation therapy to survive. Retinal degeneration may result from either retinal iron accumulation from transfusion-induced iron overload or retinal toxicity induced by iron chelation therapy. Some who were never treated with iron chelation therapy exhibited retinopathy, and others receiving iron chelation therapy had chelator-induced retinopathy. We will focus on retinal abnormalities present in individuals with β-thalassemia major viewed in light of new findings on the mechanisms and manifestations of retinal iron toxicity. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. [Electrocardiographic abnormalities in acute olanzapine poisonings].

    PubMed

    Ciszowski, Krzysztof; Sein Anand, Jacek

    2011-01-01

    Olanzapine is an atypical antipsychotic used for many years in the treatment of schizophrenia and bipolar disorder. Poisonings with this medicine can results with cardiotoxic effects in the form of ECG abnormalities. To evaluate the nature and incidence of electrocardiographic abnormalities in patients with acute olanzapine poisoning. 23 adult (mean age 38.4 +/- 15.5 years) patients with acute olanzapine poisoning, including 10 men (30.4 +/- 8.1 years) and 11 women (45.7 +/- 17.2 years), where 1 man and 1 woman were poisoned twice. The toxic serum level of olanzapine (above 100 ng/mL) was confirmed in each patient. Evaluation of electrocardiograms performed in patients in the first day of hospitalization with automatic measurement of durations of PQ, QRS and QTc and the identification of arrhythmias and conduction disorders on the basis of visual analysis of the ECG waveforms. Statistical analysis of the results using the methods of descriptive statistics. The mean durations of PQ, QRS and QTc in the study group were as follows: 135 +/- 23 ms, 91 +/- 12 ms, and 453 +/- 48 ms, respectively. The most common ECG abnormalities were prolonged QTc and supraventricular tachycardia (including sinus tachycardia) - each 22%; less common were ST-T changes (17%) and supraventricular premature complexes (9%), and only in individual cases (4%) ventricular premature complexes, bundle branch block, sinus bradycardia and atrial fibrillation were present. In the course of acute olanzapine poisonings: (1) prolonged QTc interval is quite common, but rarely leads to torsade de pointes tachycardia; (2) fast supraventricular rhythms are also common, but rarely cause irregular tachyarrhythmias, eg. atrial fibrillation; (3) conduction disorders (atrioventricular blocks, bundle branch blocks) are not typical abnormalities; (4) the observed ECG abnormalities emphasize the need of continuous ECG monitoring in these patients.

  17. MR imaging findings in the reticular formation in siblings with MPV17-related mitochondrial depletion syndrome.

    PubMed

    Merkle, A N; Nascene, D R; McKinney, A M

    2012-03-01

    Hepatocerebral MPV17-MDS is quite rare (<30 confirmed cases), with limited findings described on MR imaging. We report 2 siblings having abnormalities within the reticular formation of the lower brain stem and within the reticulospinal tracts at the cervicocranial junction on T2WI. The presence of these MR imaging findings (relative to previous reports) raises the possibility that they represent subtle but characteristic findings corresponding to clinically observed abnormalities of tone encountered with this recently described disorder.

  18. Deletion of Rbpj from postnatal endothelium leads to abnormal arteriovenous shunting in mice

    PubMed Central

    Nielsen, Corinne M.; Cuervo, Henar; Ding, Vivianne W.; Kong, Yupeng; Huang, Eric J.; Wang, Rong A.

    2014-01-01

    Arteriovenous malformations (AVMs) are tortuous vessels characterized by arteriovenous (AV) shunts, which displace capillaries and shunt blood directly from artery to vein. Notch signaling regulates embryonic AV specification by promoting arterial, as opposed to venous, endothelial cell (EC) fate. To understand the essential role of endothelial Notch signaling in postnatal AV organization, we used inducible Cre-loxP recombination to delete Rbpj, a mediator of canonical Notch signaling, from postnatal ECs in mice. Deletion of endothelial Rbpj from birth resulted in features of AVMs by P14, including abnormal AV shunting and tortuous vessels in the brain, intestine and heart. We further analyzed brain AVMs, as they pose particular health risks. Consistent with AVM pathology, we found cerebral hemorrhage, hypoxia and necrosis, and neurological deficits. AV shunts originated from capillaries (and possibly venules), with the earliest detectable morphological abnormalities in AV connections by P8. Prior to AV shunt formation, alterations in EC gene expression were detected, including decreased Efnb2 and increased Pai1, which encodes a downstream effector of TGFβ signaling. After AV shunts had formed, whole-mount immunostaining showed decreased Efnb2 and increased Ephb4 expression within AV shunts, suggesting that ECs were reprogrammed from arterial to venous identity. Deletion of Rbpj from adult ECs led to tortuosities in gastrointestinal, uterine and skin vascular beds, but had mild effects in the brain. Our results demonstrate a temporal requirement for Rbpj in postnatal ECs to maintain proper artery, capillary and vein organization and to prevent abnormal AV shunting and AVM pathogenesis. PMID:25209249

  19. Abnormal Grain Growth Suppression in Aluminum Alloys

    NASA Technical Reports Server (NTRS)

    Hales, Stephen J. (Inventor); Claytor, Harold Dale (Inventor); Alexa, Joel A. (Inventor)

    2015-01-01

    The present invention provides a process for suppressing abnormal grain growth in friction stir welded aluminum alloys by inserting an intermediate annealing treatment ("IAT") after the welding step on the article. The IAT may be followed by a solution heat treatment (SHT) on the article under effectively high solution heat treatment conditions. In at least some embodiments, a deformation step is conducted on the article under effective spin-forming deformation conditions or under effective superplastic deformation conditions. The invention further provides a welded article having suppressed abnormal grain growth, prepared by the process above. Preferably the article is characterized with greater than about 90% reduction in area fraction abnormal grain growth in any friction-stir-welded nugget.

  20. Abnormal brain activation in excoriation (skin-picking) disorder: evidence from an executive planning fMRI study

    PubMed Central

    Odlaug, Brian L.; Hampshire, Adam; Chamberlain, Samuel R.; Grant, Jon E.

    2016-01-01

    Background Excoriation (skin-picking) disorder (SPD) is a relatively common psychiatric condition whose neurobiological basis is unknown. Aims To probe the function of fronto-striatal circuitry in SPD. Method Eighteen participants with SPD and 15 matched healthy controls undertook an executive planning task (Tower of London) during functional magnetic resonance imaging (fMRI). Activation during planning was compared between groups using region of interest and whole-brain permutation cluster approaches. Results The SPD group exhibited significant functional underactivation in a cluster encompassing bilateral dorsal striatum (maximal in right caudate), bilateral anterior cingulate and right medial frontal regions. These abnormalities were, for the most part, outside the dorsal planning network typically activated by executive planning tasks. Conclusions Abnormalities of neural regions involved in habit formation, action monitoring and inhibition appear involved in the pathophysiology of SPD. Implications exist for understanding the basis of excessive grooming and the relationship of SPD with putative obsessive–compulsive spectrum disorders. PMID:26159604

  1. Gastric emptying abnormal in duodenal ulcer

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

    Holt, S.; Heading, R.C.; Taylor, T.V.

    1986-07-01

    To investigate the possibility that an abnormality of gastric emptying exists in duodenal ulcer and to determine if such an abnormality persists after ulcer healing, scintigraphic gastric emptying measurements were undertaken in 16 duodenal ulcer patients before, during, and after therapy with cimetidine; in 12 patients with pernicious anemia, and in 12 control subjects. No difference was detected in the rate or pattern of gastric emptying in duodenal ulcer patients before and after ulcer healing with cimetidine compared with controls, but emptying of the solid component of the test meal was more rapid during treatment with the drug. Comparison ofmore » emptying patterns obtained in duodenal ulcer subjects during and after cimetidine treatment with those obtained in pernicious anemia patients and controls revealed a similar relationship that was characterized by a tendency for reduction in the normal differentiation between the emptying of solid and liquid from the stomach. The similarity in emptying patterns in these groups of subjects suggests that gastric emptying of solids may be influenced by changes in the volume of gastric secretion. The failure to detect an abnormality of gastric emptying in duodenal ulcer subjects before and after ulcer healing calls into question the widespread belief that abnormally rapid gastric emptying is a feature with pathogenetic significance in duodenal ulcer disease.« less

  2. Adaptive neuro-fuzzy and expert systems for power quality analysis and prediction of abnormal operation

    NASA Astrophysics Data System (ADS)

    Ibrahim, Wael Refaat Anis

    The present research involves the development of several fuzzy expert systems for power quality analysis and diagnosis. Intelligent systems for the prediction of abnormal system operation were also developed. The performance of all intelligent modules developed was either enhanced or completely produced through adaptive fuzzy learning techniques. Neuro-fuzzy learning is the main adaptive technique utilized. The work presents a novel approach to the interpretation of power quality from the perspective of the continuous operation of a single system. The research includes an extensive literature review pertaining to the applications of intelligent systems to power quality analysis. Basic definitions and signature events related to power quality are introduced. In addition, detailed discussions of various artificial intelligence paradigms as well as wavelet theory are included. A fuzzy-based intelligent system capable of identifying normal from abnormal operation for a given system was developed. Adaptive neuro-fuzzy learning was applied to enhance its performance. A group of fuzzy expert systems that could perform full operational diagnosis were also developed successfully. The developed systems were applied to the operational diagnosis of 3-phase induction motors and rectifier bridges. A novel approach for learning power quality waveforms and trends was developed. The technique, which is adaptive neuro fuzzy-based, learned, compressed, and stored the waveform data. The new technique was successfully tested using a wide variety of power quality signature waveforms, and using real site data. The trend-learning technique was incorporated into a fuzzy expert system that was designed to predict abnormal operation of a monitored system. The intelligent system learns and stores, in compressed format, trends leading to abnormal operation. The system then compares incoming data to the retained trends continuously. If the incoming data matches any of the learned trends, an

  3. Risk of specific congenital abnormalities in offspring of women with diabetes.

    PubMed

    Nielsen, G L; Nørgard, B; Puho, E; Rothman, K J; Sørensen, H T; Czeizel, A E

    2005-06-01

    To assess the extent to which the increased risk of congenital abnormalities seen in women with pre-gestational insulin-treated diabetes mellitus is unspecific or related to the embryology of specific organs. Cases with congenital abnormalities were identified in the population-based Hungarian Congenital Abnormality Registry from 1980 to 1996 with two newborn children without congenital abnormality selected from the National Birth Registry as controls. We adjusted for parity, maternal age, and use of antipsychotic drugs. Among cases we found 63/22,843 babies with maternal diabetes compared with 50/38,151 in the control group [adjusted prevalence odds ratio (POR) 2.1; 95% CI 1.5-3.1]. The association was strongest for the following congenital abnormalities: renal agenesis (POR: 14.8; 95% CI, 3.5-62.1), obstructive congenital abnormalities of the urinary tract (POR: 4.3; 95% CI, 1.3-13.9), cardiovascular congenital abnormalities (POR: 3.4; 95% CI, 2.0-5.7), and multiple congenital abnormalities (POR: 5.0; 95% CI, 2.4-10.2). These data indicate that pre-gestational maternal diabetes is associated with strong teratogenic effects on the kidney, urinary tract, and heart, and strongly associated with multiple congenital abnormalities. We found no material association between diabetes and spinal congenital abnormalities and limb deficiencies.

  4. Macroporous mesh of nanoporous gold in electrochemical monitoring of superoxide release from skeletal muscle cells.

    PubMed

    Banan Sadeghian, Ramin; Han, Jiuhui; Ostrovidov, Serge; Salehi, Sahar; Bahraminejad, Behzad; Ahadian, Samad; Chen, Mingwei; Khademhosseini, Ali

    2017-02-15

    Real-time monitoring of metabolically relevant biochemicals released in minuscule amounts is of utmost diagnostic importance. Superoxide anion as a primary member of reactive oxygen species, has physiological and pathological effects that depend on its concentration and release rate. Here we present fabrication and successfully testing of a highly sensitive electrochemical biosensor featuring a three-dimensional macroporous mesh of nanoporous gold tailored to measure the dynamics of extracellular superoxide concentration. Wide and accessible surface of the mesh combined with high porosity of the thin nanoporous gold coating enables capturing the analyte in pico- to nano-molar ranges. The mesh is functionalized with cytochrome-c (cyt-c) and incorporated as a working electrode to measure the release rate of drug-induced superoxides from C2C12 cells through a porous membrane. The device displays a considerably improved superoxide sensitivity of 7.29nAnM - 1 cm - 2 and a low level of detection of 70pM. Such sensitivity is orders of magnitude higher than any similar enzyme-based electrochemical superoxide sensor and is attributed to the facile diffusion of the analyte through the well-spread nanofeatured gold skin. Superoxide generation rates captured from monolayer myoblast cultures containing about 4×10 4 cells, varied from 1.0 to 9.0nMmin - 1 in a quasi-linear fashion as a function of drug concentration. This work provides a platform for the development of highly sensitive molecular electrochemical biosensors. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Chromosome and molecular abnormalities in myelodysplastic syndromes.

    PubMed

    Fenaux, Pierre

    2001-06-01

    Cytogenetic abnormalities are seen in approximately 50% of cases of myelodysplastic syndrome (MDS) and 80% of cases of secondary MDS (following chemotherapy or radiotherapy). These abnormalities generally consist of partial or complete chromosome deletion or addition (del5q, -7, +8, -Y, del20q), whereas balanced or unbalanced translocations are rarely found in MDS. Fluorescence hybridization techniques (fluorescence in situ hybridization [FISH], multiplex FISH, and spectral karyotyping) are useful in detecting chromosomal anomalies in cases in which few mitoses are obtained or rearrangements are complex. Ras mutations are the molecular abnormalities most frequently found in MDS, followed by p15 gene hypermethylation, FLT3 duplications, and p53 mutations, but none of these abnormalities are specific for MDS. The rare cases of balanced translocations in MDS have allowed the identification of genes whose rearrangements appear to play a role in the pathogenesis of some cases of MDS. These genes include MDS1-EVI1 in t(3;3) or t(3;21) translocations, TEL in t(5;12), HIP1 in t(5;7), MLF1 in t(3;5), and MEL1 in t(1;3). Genes more frequently implicated in the pathogenesis of MDS cases, such as those involving del5q, remain unknown, although some candidate genes are currently being studied. Cytogenetic and known molecular abnormalities generally carry a poor prognosis in MDS and can be incorporated into prognostic scoring systems such as the International Prognostic Scoring System.

  6. Mechanisms and consequences of paternally transmitted chromosomal abnormalities

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

    Marchetti, F; Wyrobek, A J

    Paternally transmitted chromosomal damage has been associated with pregnancy loss, developmental and morphological defects, infant mortality, infertility, and genetic diseases in the offspring including cancer. There is epidemiological evidence linking paternal exposure to occupational or environmental agents with an increased risk of abnormal reproductive outcomes. There is also a large body of literature on germ cell mutagenesis in rodents showing that treatment of male germ cells with mutagens has dramatic consequences on reproduction producing effects such as those observed in human epidemiological studies. However, we know very little about the etiology, transmission and early embryonic consequences of paternally-derived chromosomal abnormalities.more » The available evidence suggests that: (1) there are distinct patterns of germ cell-stage differences in the sensitivity of induction of transmissible genetic damage with male postmeiotic cells being the most sensitive; (2) cytogenetic abnormalities at first metaphase after fertilization are critical intermediates between paternal exposure and abnormal reproductive outcomes; and, (3) there are maternally susceptibility factors that may have profound effects on the amount of sperm DNA damage that is converted into chromosomal aberrations in the zygote and directly affect the risk for abnormal reproductive outcomes.« less

  7. Abnormal Uterine Bleeding: American College of Nurse-Midwives.

    PubMed

    2016-07-01

    Variations in uterine bleeding, termed abnormal uterine bleeding, occur commonly among women and often are physiologic in nature with no significant consequences. However, abnormal uterine bleeding can cause significant distress to women or may signify an underlying pathologic condition. Most women experience variations in menstrual and perimenstrual bleeding in their lifetimes; therefore, the ability of the midwife to differentiate between normal and abnormal bleeding is a key diagnostic skill. A comprehensive history and use of the PALM-COEIN classification system will provide clear guidelines for clinical management, evidence-based treatment, and an individualized plan of care. The purpose of this Clinical Bulletin is to define and describe classifications of abnormal uterine bleeding, review updated terminology, and identify methods of assessment and treatment using a woman-centered approach. © 2016 by the American College of Nurse-Midwives.

  8. Alteration in cellular acetylcholine influences dauer formation in Caenorhabditis elegans.

    PubMed

    Lee, Jeeyong; Kim, Kwang-Youl; Paik, Young-Ki

    2014-02-01

    Altered acetylcholine (Ach) homeostasis is associated with loss of viability in flies, developmental defects in mice, and cognitive deficits in human. Here, we assessed the importance of Ach in Caenorhabditis elegans development, focusing on the role of Ach during dauer formation. We found that dauer formation was disturbed in choline acetyltransferase (cha-1) and acetylcholinesterase (ace) mutants defective in Ach biosynthesis and degradation, respectively. When examined the potential role of G-proteins in dauer formation, goa-1 and egl-30 mutant worms, expressing mutated versions of mammalian G(o) and G(q) homolog, respectively, showed some abnormalities in dauer formation. Using quantitative mass spectrometry, we also found that dauer larvae had lower Ach content than did reproductively grown larvae. In addition, a proteomic analysis of acetylcholinesterase mutant worms, which have excessive levels of Ach, showed differential expression of metabolic genes. Collectively, these results indicate that alterations in Ach release may influence dauer formation in C. elegans.

  9. Protective role of RAD50 on chromatin bridges during abnormal cytokinesis.

    PubMed

    Schröder-Heurich, Bianca; Wieland, Britta; Lavin, Martin F; Schindler, Detlev; Dörk, Thilo

    2014-03-01

    Faithful chromosome segregation is required for preserving genomic integrity. Failure of this process may entail chromatin bridges preventing normal cytokinesis. To test whether RAD50, a protein normally involved in DNA double-strand break repair, is involved in abnormal cytokinesis and formation of chromatin bridges, we used immunocytochemical and protein interaction assays. RAD50 localizes to chromatin bridges during aberrant cytokinesis and subsequent stages of the cell cycle, either decorating the entire bridge or focally accumulating at the midbody zone. Ionizing radiation led to an ∼4-fold increase in the rate of chromatin bridges in an ataxia telangiectatica mutated (ATM)-dependent manner in human RAD50-proficient fibroblasts but not in RAD50-deficient cells. Cells with a RAD50-positive chromatin bridge were able to continue cell cycling and to progress through S phase (44%), whereas RAD50 knockdown caused a deficiency in chromatin bridges as well as an ∼4-fold prolonged duration of mitosis. RAD50 colocalized and directly interacted with Aurora B kinase and phospho-histone H3, and Aurora B kinase inhibition led to a deficiency in RAD50-positive bridges. Based on these observations, we propose that RAD50 is a crucial factor for the stabilization and shielding of chromatin bridges. Our study provides evidence for a hitherto unknown role of RAD50 in abnormal cytokinesis.

  10. Three-dimensional ordered macroporous MnO2/carbon nanocomposites as high-performance electrodes for asymmetric supercapacitors.

    PubMed

    Yang, Chunzhen; Zhou, Ming; Xu, Qian

    2013-12-07

    MnO2/carbon composites with ultrathin MnO2 nanofibers (diameter of 5-10 nm) uniformly deposited on three dimensional ordered macroporous (3DOM) carbon frameworks were fabricated via a self-limiting redox process. The MnO2 nanofibers provide a large surface area for charge storage, whereas the 3DOM carbon serves as a desirable supporting material providing rapid ion and electron transport through the composite electrodes. Cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy (EIS) were used to characterize the capacitive performance of these composites. Optimization of the composition results in a composite with 57 wt% MnO2 content, which gives both a high specific capacitance (234 F g(-1) at a discharge current of 0.1 A g(-1)) and good rate capability (52% retention of the capacitance at 5 A g(-1)). An asymmetric supercapacitor was fabricated by assembling the optimized MnO2/carbon composite as the positive electrode and 3DOM carbon as the negative electrode. The asymmetric supercapacitor exhibits superior electrochemical performances, which can be reversibly charged and discharged at a maximum cell voltage of 2.0 V in 1.0 M Na2SO4 aqueous electrolyte, delivering both high energy density (30.2 W h kg(-1)) and power density (14.5 kW kg(-1)). Additionally, the asymmetric supercapacitor exhibits an excellent cycle life, with 95% capacitance retained after 1000 cycles.

  11. Biologically and mechanically driven design of an RGD-mimetic macroporous foam for adipose tissue engineering applications.

    PubMed

    Rossi, Eleonora; Gerges, Irini; Tocchio, Alessandro; Tamplenizza, Margherita; Aprile, Paola; Recordati, Camilla; Martello, Federico; Martin, Ivan; Milani, Paolo; Lenardi, Cristina

    2016-10-01

    Despite clinical treatments for adipose tissue defects, in particular breast tissue reconstruction, have certain grades of efficacy, many drawbacks are still affecting the long-term survival of new formed fat tissue. To overcome this problem, in the last decades, several scaffolding materials have been investigated in the field of adipose tissue engineering. However, a strategy able to recapitulate a suitable environment for adipose tissue reconstruction and maintenance is still missing. To address this need, we adopted a biologically and mechanically driven design to fabricate an RGD-mimetic poly(amidoamine) oligomer macroporous foam (OPAAF) for adipose tissue reconstruction. The scaffold was designed to fulfil three fundamental criteria: capability to induce cell adhesion and proliferation, support of in vivo vascularization and match of native tissue mechanical properties. Poly(amidoamine) oligomers were formed into soft scaffolds with hierarchical porosity through a combined free radical polymerization and foaming reaction. OPAAF is characterized by a high water uptake capacity, progressive degradation kinetics and ideal mechanical properties for adipose tissue reconstruction. OPAAF's ability to support cell adhesion, proliferation and adipogenesis was assessed in vitro using epithelial, fibroblast and endothelial cells (MDCK, 3T3L1 and HUVEC respectively). In addition, in vivo subcutaneous implantation in murine model highlighted OPAAF potential to support both adipogenesis and vessels infiltration. Overall, the reported results support the use of OPAAF as a scaffold for engineered adipose tissue construct. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Quantum dots electrochemical aptasensor based on three-dimensionally ordered macroporous gold film for the detection of ATP.

    PubMed

    Zhou, Jinjun; Huang, Haiping; Xuan, Jie; Zhang, Jianrong; Zhu, Jun-Jie

    2010-10-15

    A sensitive electrochemical aptasensor was successfully fabricated for the detection of adenosine triphosphate (ATP) by combining three-dimensionally ordered macroporous (3DOM) gold film and quantum dots (QDs). The 3DOM gold film was electrochemically fabricated with an inverted opal template, making the active surface area of the electrode up to 9.52 times larger than that of a classical bare flat one. 5′-thiolated ATP-binding aptamer (ABA) was first assembled onto the 3DOM gold film via sulfur–gold affinity. Then, 5′-biotinated complementary strand (BCS) was immobilized via hybridization reaction to form the DNA/DNA duplex. Since the tertiary structure of the aptamer was stabilized in the presence of target ATP, the duplex can be denatured to liberate BCS. The reaction was monitored by electrochemical stripping analysis of dissolved QDs which were bound to the residual BCS through biotin-streptavidin system. The decrease of peak current was proportional to the amount of ATP. The unique interconnected structure in 3DOM gold film along with the "built-in" preconcentration remarkably improved the sensitivity. ATP detection with high selectivity, wide linear dynamic range of 4 orders of magnitude and high sensitivity down to 0.01 nm were achieved. The results demonstrated that the novel strategy was feasible for sensitive ATP assay and provided a promising model for the detection of small molecules.

  13. Nuclei pulposi formation from the embryonic notochord occurs normally in GDF-5-deficient mice.

    PubMed

    Maier, Jennifer A; Harfe, Brian D

    2011-11-15

    The transition of the mouse embryonic notochord into nuclei pulposi was determined ("fate mapped") in vivo in growth and differentiating factor-5 (GDF-5)-null mice using the Shhcre and R26R alleles. To determine whether abnormal nuclei pulposi formation from the embryonic notochord was responsible for defects present in adult nuclei pulposi of Gdf-5-null mice. The development, maintenance, and degeneration of the intervertebral disc are not understood. Previously, we demonstrated that all cells in the adult nucleus pulposus of normal mice are derived from the embryonic notochord. Gdf-5-null mice have been reported to contain intervertebral discs in which the nucleus pulposus is abnormal. It is currently unclear if disc defects in Gdf-5-null mice arise during the formation of nuclei pulposi from the notochord during embryogenesis or result from progressive postnatal degeneration of nuclei pulposi. Gdf-5 messenger RNA expression was examined in the discs of wild-type embryos by RNA in situ hybridization to determine when and where this gene was expressed. To examine nucleus pulposus formation in Gdf-5-null mice, intervertebral discs in which embryonic notochord cells were marked were analyzed in newborn and 24-week-old mice. Our Gdf-5 messenger RNA in situ experiments determined that this gene is localized to the annulus fibrosus and not the nucleus pulposus in mouse embryos. Notochord fate-mapping experiments revealed that notochord cells in Gdf-5-null mice correctly form nuclei pulposi. Our data suggest that the defects reported in the nucleus pulposus of adult Gdf-5-null mice do not result from abnormal patterning of the embryonic notochord. The use of mouse alleles to mark cells that produce all cell types that reside in the adult nucleus pulposus will allow for a detailed examination of disc formation in other mouse mutants that have been reported to contain disc defects.

  14. The nurse response to abnormal vital sign recording in the emergency department.

    PubMed

    Johnson, Kimberly D; Mueller, Lindsey; Winkelman, Chris

    2017-01-01

    To examine what occurs after a recorded observation of at least one abnormal vital sign in the emergency department. The aims were to determine how often abnormal vital signs were recorded, what interventions were documented, and what factors were associated with documented follow-up for abnormal vital signs. Monitoring quality of care, and preventing or intervening before harm occurs to patients are central to nurses' roles. Abnormal vital signs have been associated with poor patient outcomes and require follow-up after the observation of abnormal readings to prevent patient harm related to a deteriorating status. This documentation is important to quality and safety of care. Observational, retrospective chart review. Modified Early Warning Score was calculated for all recorded vital signs for 195 charts. Comparisons were made between groups: (1) no abnormal vital signs, (2) abnormal vital sign present, but normal Modified Early Warning Score and (3) critically abnormal Modified Early Warning Score. About 62·1% of charts had an abnormal vital sign documented. Critically abnormal values were present in 14·9%. No documentation was present in 44·6% of abnormal cases. When interventions were documented, it was usually to notify the physician. The timing within the emergency department visit when the abnormalities were observed and the degree of abnormality had significant relationships to the presence of documentation. It is doubtful that nurses do not recognise abnormalities because more severely abnormal vital signs were more likely to have documented follow-up. Perhaps the interruptive nature of the emergency department or the prioritised actions of the nurse impacted documentation within this study. Further research is required to determine why follow-up is not being documented. To ensure safety and quality of patient care, accurate documentation of responses to abnormal vital signs is required. © 2016 John Wiley & Sons Ltd.

  15. Lung volumes and emphysema in smokers with interstitial lung abnormalities.

    PubMed

    Washko, George R; Hunninghake, Gary M; Fernandez, Isis E; Nishino, Mizuki; Okajima, Yuka; Yamashiro, Tsuneo; Ross, James C; Estépar, Raúl San José; Lynch, David A; Brehm, John M; Andriole, Katherine P; Diaz, Alejandro A; Khorasani, Ramin; D'Aco, Katherine; Sciurba, Frank C; Silverman, Edwin K; Hatabu, Hiroto; Rosas, Ivan O

    2011-03-10

    Cigarette smoking is associated with emphysema and radiographic interstitial lung abnormalities. The degree to which interstitial lung abnormalities are associated with reduced total lung capacity and the extent of emphysema is not known. We looked for interstitial lung abnormalities in 2416 (96%) of 2508 high-resolution computed tomographic (HRCT) scans of the lung obtained from a cohort of smokers. We used linear and logistic regression to evaluate the associations between interstitial lung abnormalities and HRCT measurements of total lung capacity and emphysema. Interstitial lung abnormalities were present in 194 (8%) of the 2416 HRCT scans evaluated. In statistical models adjusting for relevant covariates, interstitial lung abnormalities were associated with reduced total lung capacity (-0.444 liters; 95% confidence interval [CI], -0.596 to -0.292; P<0.001) and a lower percentage of emphysema defined by lung-attenuation thresholds of -950 Hounsfield units (-3%; 95% CI, -4 to -2; P<0.001) and -910 Hounsfield units (-10%; 95% CI, -12 to -8; P<0.001). As compared with participants without interstitial lung abnormalities, those with abnormalities were more likely to have a restrictive lung deficit (total lung capacity <80% of the predicted value; odds ratio, 2.3; 95% CI, 1.4 to 3.7; P<0.001) and were less likely to meet the diagnostic criteria for chronic obstructive pulmonary disease (COPD) (odds ratio, 0.53; 95% CI, 0.37 to 0.76; P<0.001). The effect of interstitial lung abnormalities on total lung capacity and emphysema was dependent on COPD status (P<0.02 for the interactions). Interstitial lung abnormalities were positively associated with both greater exposure to tobacco smoke and current smoking. In smokers, interstitial lung abnormalities--which were present on about 1 of every 12 HRCT scans--were associated with reduced total lung capacity and a lesser amount of emphysema. (Funded by the National Institutes of Health and the Parker B. Francis Foundation

  16. Abnormal Head Position in Infantile Nystagmus Syndrome

    PubMed Central

    Noval, Susana; González-Manrique, Mar; Rodríguez-Del Valle, José María; Rodríguez-Sánchez, José María

    2011-01-01

    Infantile nystagmus is an involuntary, bilateral, conjugate, and rhythmic oscillation of the eyes which is present at birth or develops within the first 6 months of life. It may be pendular or jerk-like and, its intensity usually increases in lateral gaze, decreasing with convergence. Up to 64% of all patients with nystagmus also present strabismus, and even more patients have an abnormal head position. The abnormal head positions are more often horizontal, but they may also be vertical or take the form of a tilt, even though the nystagmus itself is horizontal. The aim of this article is to review available information about the origin and treatment of the abnormal head position associated to nystagmus, and to describe our treatment strategies. PMID:24533187

  17. Advances in understanding paternally transmitted Chromosomal Abnormalities

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

    Marchetti, F; Sloter, E; Wyrobek, A J

    2001-03-01

    Multicolor FISH has been adapted for detecting the major types of chromosomal abnormalities in human sperm including aneuploidies for clinically-relevant chromosomes, chromosomal aberrations including breaks and rearrangements, and other numerical abnormalities. The various sperm FISH assays have been used to evaluate healthy men, men of advanced age, and men who have received mutagenic cancer therapy. The mouse has also been used as a model to investigate the mechanism of paternally transmitted genetic damage. Sperm FISH for the mouse has been used to detect chromosomally abnormal mouse sperm, while the PAINT/DAPI analysis of mouse zygotes has been used to evaluate themore » types of chromosomal defects that can be paternally transmitted to the embryo and their effects on embryonic development.« less

  18. Nightmare and Abnormal Dreams: Rare Side Effects of Metformin?

    PubMed Central

    Yanto, Theo Audi; Kosasih, Felicia Nathania

    2018-01-01

    Background Metformin is widely known as an antidiabetic agent which has significant gastrointestinal side effects, but nightmares and abnormal dreams as its adverse reactions are not well reported. Case Presentation Herein we present a case of 56-year-old male patient with no known history of recurrent nightmares and sleep disorder, experiencing nightmare and abnormal dreams directly after consumption of 750 mg extended release metformin. He reported his dream as an unpleasant experience which awakened him at night with negative feelings. The nightmare only lasted for a night, but his dreams every night thereafter seemed abnormal. The dreams were vivid and indescribable. The disappearance and occurrence of abnormal dreams ensued soon after the drug was discontinued and rechallenged. The case was assessed using Naranjo Adverse Drug Reaction (ADR) probability scale and resulted as probable causality. Conclusion Metformin might be the underlying cause of nightmare and abnormal dreams in this patient. More studies are needed to confirm the association and causality of this findings. PMID:29581904

  19. Motor Control Abnormalities in Parkinson’s Disease

    PubMed Central

    Mazzoni, Pietro; Shabbott, Britne; Cortés, Juan Camilo

    2012-01-01

    The primary manifestations of Parkinson’s disease are abnormalities of movement, including movement slowness, difficulties with gait and balance, and tremor. We know a considerable amount about the abnormalities of neuronal and muscle activity that correlate with these symptoms. Motor symptoms can also be described in terms of motor control, a level of description that explains how movement variables, such as a limb’s position and speed, are controlled and coordinated. Understanding motor symptoms as motor control abnormalities means to identify how the disease disrupts normal control processes. In the case of Parkinson’s disease, movement slowness, for example, would be explained by a disruption of the control processes that determine normal movement speed. Two long-term benefits of understanding the motor control basis of motor symptoms include the future design of neural prostheses to replace the function of damaged basal ganglia circuits, and the rational design of rehabilitation strategies. This type of understanding, however, remains limited, partly because of limitations in our knowledge of normal motor control. In this article, we review the concept of motor control and describe a few motor symptoms that illustrate the challenges in understanding such symptoms as motor control abnormalities. PMID:22675667

  20. Abnormal interhemispheric connectivity in male psychopathic offenders.

    PubMed

    Hoppenbrouwers, Sylco S; De Jesus, Danilo R; Sun, Yinming; Stirpe, Tania; Hofman, Dennis; McMaster, Jeff; Hughes, Ginny; Daskalakis, Zafiris J; Schutter, Dennis J L G

    2014-01-01

    Psychopathic offenders inevitably violate interpersonal norms and frequently resort to aggressive and criminal behaviour. The affective and cognitive deficits underlying these behaviours have been linked to abnormalities in functional interhemispheric connectivity. However, direct neurophysiological evidence for dysfunctional connectivity in psychopathic offenders is lacking. We used transcranial magnetic stimulation combined with electroencephalography to examine interhemispheric connectivity in the dorsolateral and motor cortex in a sample of psychopathic offenders and healthy controls. We also measured intracortical inhibition and facilitation over the left and right motor cortex to investigate the effects of local cortical processes on interhemispheric connectivity. We enrolled 17 psychopathic offenders and 14 controls in our study. Global abnormalities in right to left functional connectivity were observed in psychopathic offenders compared with controls. Furthermore, in contrast to controls, psychopathic offenders showed increased intracortical inhibition in the right, but not the left, hemisphere. The relatively small sample size limited the sensitivity to show that the abnormalities in interhemispheric connectivity were specifically related to the dorsolateral prefrontal cortex in psychopathic offenders. To our knowledge, this study provides the first neurophysiological evidence for abnormal interhemispheric connectivity in psychopathic offenders and may further our understanding of the disruptive antisocial behaviour of these offenders.

  1. The psychosocial impact of an abnormal cervical smear result.

    PubMed

    Drolet, Mélanie; Brisson, Marc; Maunsell, Elizabeth; Franco, Eduardo L; Coutlée, François; Ferenczy, Alex; Fisher, William; Mansi, James A

    2012-10-01

    Data on the impact of abnormal cervical smear results on health-related quality of life (HrQoL) are scarce. We aimed to (i) prospectively assess the HrQoL of women who were informed of an abnormal smear result; (ii) identify predictors of greater negative psychosocial impact of an abnormal result; and (iii) prospectively estimate the quality-adjusted life-years (QALYs) lost following an abnormal result. Between 08/2006 and 08/2008, 492 women with an abnormal result and 460 women with a normal result, frequency matched for age and clinic, were recruited across Canada. HrQoL was measured at recruitment and 4 and 12 weeks later with the EuroQol, Short Form-12, short Spielberg State-Trait Anxiety Inventory (STAI) and HPV Impact Profile. Three blocks of potential predictors of higher psychosocial impact were tested by hierarchical modeling: (i) socio-demographics; (ii) sexual activity; and (iii) smear result severity, communication, and understanding. Receiving an abnormal result significantly increased anxiety (STAI mean difference between both groups = 8.3). Initial anxiety decreased over time for the majority of women. However, 35% of women had clinically meaningful anxiety at 12 weeks (i.e. STAI scores ≥0.5 standard deviation of the controls). These women reported a lower socio-economic level, did not completely understand the information about their result and perceived themselves at higher risk of cancer. QALY lost following an abnormal result were between 0.007 and 0.009. Receiving an abnormal smear has a statistically significant and clinically meaningful negative impact on mental health. However, this negative impact subsides after 12 weeks for the majority of women. Copyright © 2011 John Wiley & Sons, Ltd.

  2. v-Src-driven transformation is due to chromosome abnormalities but not Src-mediated growth signaling.

    PubMed

    Honda, Takuya; Morii, Mariko; Nakayama, Yuji; Suzuki, Ko; Yamaguchi, Noritaka; Yamaguchi, Naoto

    2018-01-18

    v-Src is the first identified oncogene product and has a strong tyrosine kinase activity. Much of the literature indicates that v-Src expression induces anchorage-independent and infinite cell proliferation through continuous stimulation of growth signaling by v-Src activity. Although all of v-Src-expressing cells are supposed to form transformed colonies, low frequencies of v-Src-induced colony formation have been observed so far. Using cells that exhibit high expression efficiencies of inducible v-Src, we show that v-Src expression causes cell-cycle arrest through p21 up-regulation despite ERK activation. v-Src expression also induces chromosome abnormalities and unexpected suppression of v-Src expression, leading to p21 down-regulation and ERK inactivation. Importantly, among v-Src-suppressed cells, only a limited number of cells gain the ability to re-proliferate and form transformed colonies. Our findings provide the first evidence that v-Src-driven transformation is attributed to chromosome abnormalities, but not continuous stimulation of growth signaling, possibly through stochastic genetic alterations.

  3. Creating 3D Hierarchical Carbon Architectures with Micro-, Meso-, and Macropores via a Simple Self-Blowing Strategy for a Flow-through Deionization Capacitor.

    PubMed

    Zhao, Shanshan; Yan, Tingting; Wang, Hui; Zhang, Jianping; Shi, Liyi; Zhang, Dengsong

    2016-07-20

    In this work, 3D hierarchical carbon architectures (3DHCAs) with micro-, meso-, and macropores were prepared via a simple self-blowing strategy as highly efficient electrodes for a flow-through deionization capacitor (FTDC). The obtained 3DHCAs have a hierarchically porous structure, large accessible specific surface area (2061 m(2) g(-1)), and good wettability. The electrochemical tests show that the 3DHCA electrode has a high specific capacitance and good electric conductivity. The deionization experiments demonstrate that the 3DHCA electrodes possess a high deionization capacity of 17.83 mg g(-1) in a 500 mg L(-1) NaCl solution at 1.2 V. Moreover, the 3DHCA electrodes present a fast deionization rate in 100-500 mg L(-1) NaCl solutions at 0.8-1.4 V. The 3DHCA electrodes also present a good regeneration behavior in the reiterative regeneration test. These above factors render the 3DHCAs a promising FTDC electrode material.

  4. 42 CFR 37.54 - Notification of abnormal radiographic findings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... shape or size, tuberculosis, lung cancer, or any other significant abnormal findings other than..., tuberculosis, cancer, complicated pneumoconiosis, and any other significant abnormal findings, NIOSH will...

  5. ILK modulates epithelial polarity and matrix formation in hair follicles.

    PubMed

    Rudkouskaya, Alena; Welch, Ian; Dagnino, Lina

    2014-03-01

    Hair follicle morphogenesis requires coordination of multiple signals and communication between its epithelial and mesenchymal constituents. Cell adhesion protein platforms, which include integrins and integrin-linked kinase (ILK), are critical for hair follicle formation. However, their precise contribution to this process is poorly understood. We show that in the absence of ILK, the hair follicle matrix lineage fails to develop, likely due to abnormalities in development of apical-basal cell polarity, as well as in laminin-511 and basement membrane assembly at the tip of the hair bud. These defects also result in impaired specification of hair matrix and absence of precortex and inner sheath root cell lineages. The molecular pathways affected in ILK-deficient follicles are similar to those in the absence of epidermal integrin β1 and include Wnt, but not sonic hedgehog, signaling. ILK-deficient hair buds also show abnormalities in the dermal papilla. Addition of exogenous laminin-511 restores morphological and molecular markers associated with hair matrix formation, indicating that ILK regulates hair bud cell polarity and functions upstream from laminin-511 assembly to regulate the developmental progression of hair follicles beyond the germ stage.

  6. ILK modulates epithelial polarity and matrix formation in hair follicles

    PubMed Central

    Rudkouskaya, Alena; Welch, Ian; Dagnino, Lina

    2014-01-01

    Hair follicle morphogenesis requires coordination of multiple signals and communication between its epithelial and mesenchymal constituents. Cell adhesion protein platforms, which include integrins and integrin-linked kinase (ILK), are critical for hair follicle formation. However, their precise contribution to this process is poorly understood. We show that in the absence of ILK, the hair follicle matrix lineage fails to develop, likely due to abnormalities in development of apical–basal cell polarity, as well as in laminin-511 and basement membrane assembly at the tip of the hair bud. These defects also result in impaired specification of hair matrix and absence of precortex and inner sheath root cell lineages. The molecular pathways affected in ILK-deficient follicles are similar to those in the absence of epidermal integrin β1 and include Wnt, but not sonic hedgehog, signaling. ILK-deficient hair buds also show abnormalities in the dermal papilla. Addition of exogenous laminin-511 restores morphological and molecular markers associated with hair matrix formation, indicating that ILK regulates hair bud cell polarity and functions upstream from laminin-511 assembly to regulate the developmental progression of hair follicles beyond the germ stage. PMID:24371086

  7. Eye movement abnormalities in essential tremor

    PubMed Central

    Plinta, Klaudia; Krzak-Kubica, Agnieszka; Zajdel, Katarzyna; Falkiewicz, Marcel; Dylak, Jacek; Ober, Jan; Szczudlik, Andrzej; Rudzińska, Monika

    2016-01-01

    Abstract Essential tremor (ET) is the most prevalent movement disorder, characterized mainly by an action tremor of the arms. Only a few studies published as yet have assessed oculomotor abnormalities in ET and their results are unequivocal. The aim of this study was to assess the oculomotor abnormalities in ET patients compared with the control group and to find the relationship between oculomotor abnormalities and clinical features of ET patients. We studied 50 ET patients and 42 matched by age and gender healthy controls. Saccadometer Advanced (Ober Consulting, Poland) was used to investigate reflexive, pace-induced and cued saccades and conventional electrooculography for evaluation of smooth pursuit and fixation. The severity of the tremor was assessed by the Clinical Rating Scale for Tremor. Significant differences between ET patients and controls were found for the incidence of reflexive saccades dysmetria and deficit of smooth pursuit. Reflexive saccades dysmetria was more frequent in patients in the second and third phase of ET compared to the first phase. The reflexive saccades latency increase was correlated with severity of the tremor. In conclusion, oculomotor abnormalities were significantly more common in ET patients than in healthy subjects. The most common oculomotor disturbances in ET were reflexive saccades dysmetria and slowing of smooth pursuit. The frequency of reflexive saccades dysmetria increased with progression of ET. The reflexive saccades latency increase was related to the severity of tremor. PMID:28149393

  8. Bioreactor culture duration of engineered constructs influences bone formation by mesenchymal stem cells.

    PubMed

    Mitra, Debika; Whitehead, Jacklyn; Yasui, Osamu W; Leach, J Kent

    2017-11-01

    Perfusion culture of mesenchymal stem cells (MSCs) seeded in biomaterial scaffolds provides nutrients for cell survival, enhances extracellular matrix deposition, and increases osteogenic cell differentiation. However, there is no consensus on the appropriate perfusion duration of cellular constructs in vitro to boost their bone forming capacity in vivo. We investigated this phenomenon by culturing human MSCs in macroporous composite scaffolds in a direct perfusion bioreactor and compared their response to scaffolds in continuous dynamic culture conditions on an XYZ shaker. Cell seeding in continuous perfusion bioreactors resulted in more uniform MSC distribution than static seeding. We observed similar calcium deposition in all composite scaffolds over 21 days of bioreactor culture, regardless of pore size. Compared to scaffolds in dynamic culture, perfused scaffolds exhibited increased DNA content and expression of osteogenic markers up to 14 days in culture that plateaued thereafter. We then evaluated the effect of perfusion culture duration on bone formation when MSC-seeded scaffolds were implanted in a murine ectopic site. Human MSCs persisted in all scaffolds at 2 weeks in vivo, and we observed increased neovascularization in constructs cultured under perfusion for 7 days relative to those cultured for 1 day within each gender. At 8 weeks post-implantation, we observed greater bone volume fraction, bone mineral density, tissue ingrowth, collagen density, and osteoblastic markers in bioreactor constructs cultured for 14 days compared to those cultured for 1 or 7 days, and acellular constructs. Taken together, these data demonstrate that culturing MSCs under perfusion culture for at least 14 days in vitro improves the quantity and quality of bone formation in vivo. This study highlights the need for optimizing in vitro bioreactor culture duration of engineered constructs to achieve the desired level of bone formation. Copyright © 2017 Elsevier Ltd. All

  9. Three-dimensional bioprinting of embryonic stem cells directs highly uniform embryoid body formation.

    PubMed

    Ouyang, Liliang; Yao, Rui; Mao, Shuangshuang; Chen, Xi; Na, Jie; Sun, Wei

    2015-11-04

    With the ability to manipulate cells temporarily and spatially into three-dimensional (3D) tissue-like construct, 3D bioprinting technology was used in many studies to facilitate the recreation of complex cell niche and/or to better understand the regulation of stem cell proliferation and differentiation by cellular microenvironment factors. Embryonic stem cells (ESCs) have the capacity to differentiate into any specialized cell type of the animal body, generally via the formation of embryoid body (EB), which mimics the early stages of embryogenesis. In this study, extrusion-based 3D bioprinting technology was utilized for biofabricating ESCs into 3D cell-laden construct. The influence of 3D printing parameters on ESC viability, proliferation, maintenance of pluripotency and the rule of EB formation was systematically studied in this work. Results demonstrated that ESCs were successfully printed with hydrogel into 3D macroporous construct. Upon process optimization, about 90% ESCs remained alive after the process of bioprinting and cell-laden construct formation. ESCs continued proliferating into spheroid EBs in the hydrogel construct, while retaining the protein expression and gene expression of pluripotent markers, like octamer binding transcription factor 4, stage specific embryonic antigen 1 and Nanog. In this novel technology, EBs were formed through cell proliferation instead of aggregation, and the quantity of EBs was tuned by the initial cell density in the 3D bioprinting process. This study introduces the 3D bioprinting of ESCs into a 3D cell-laden hydrogel construct for the first time and showed the production of uniform, pluripotent, high-throughput and size-controllable EBs, which indicated strong potential in ESC large scale expansion, stem cell regulation and fabrication of tissue-like structure and drug screening studies.

  10. Abnormal Behavior in Relation to Cage Size in Rhesus Monkeys

    ERIC Educational Resources Information Center

    Paulk, H. H.; And Others

    1977-01-01

    Examines the effects of cage size on stereotyped and normal locomotion and on other abnormal behaviors in singly caged animals, whether observed abnormal behaviors tend to co-occur, and if the development of an abnormal behavior repertoire leads to reduction in the number of normal behavior categories. (Author/RK)

  11. Telomere dysfunction and chromosome structure modulate the contribution of individual chromosomes in abnormal nuclear morphologies.

    PubMed

    Pampalona, J; Soler, D; Genescà, A; Tusell, L

    2010-01-05

    The cytokinesis-block micronucleus assay has emerged as a biomarker of chromosome damage relevant to cancer. Although it was initially developed to measure micronuclei, it is also useful for measuring nucleoplasmic bridges and nuclear buds. Abnormal nuclear morphologies are frequently observed in malignant tissues and short-term tumour cell cultures. Changes in chromosome structure and number resulting from chromosome instability are important factors in oncogenesis. Telomeres have become key players in the initiation of chromosome instability related to carcinogenesis by means of breakage-fusion-bridge cycles. To better understand the connection between telomere dysfunction and the appearance of abnormal nuclear morphologies, we have characterised the presence of micronuclei, nucleoplasmic bridges and nuclear buds in human mammary primary epithelial cells. These cells can proliferate beyond the Hayflick limit by spontaneously losing expression of the p16(INK4a) protein. Progressive telomere shortening leads to the loss of the capping function, and the appearance of end-to-end chromosome fusions that can enter into breakage-fusion-bridge cycles generating massive chromosomal instability. In human mammary epithelial cells, different types of abnormal nuclear morphologies were observed, however only nucleoplasmatic bridges and buds increased significantly with population doublings. Fluorescent in situ hybridisation using centromeric and painting specific probes for chromosomes with eroded telomeres has revealed that these chromosomes are preferentially included in the different types of abnormal nuclear morphologies observed, thus reflecting their common origin. Accordingly, real-time imaging of cell divisions enabled us to determine that anaphase bridge resolution was mainly through chromatin breakage and the formation of symmetric buds in daughter nuclei. Few micronuclei emerged in this cell system thus validating the scoring of nucleoplasmic bridges and nuclear

  12. Detection of dominant flow and abnormal events in surveillance video

    NASA Astrophysics Data System (ADS)

    Kwak, Sooyeong; Byun, Hyeran

    2011-02-01

    We propose an algorithm for abnormal event detection in surveillance video. The proposed algorithm is based on a semi-unsupervised learning method, a kind of feature-based approach so that it does not detect the moving object individually. The proposed algorithm identifies dominant flow without individual object tracking using a latent Dirichlet allocation model in crowded environments. It can also automatically detect and localize an abnormally moving object in real-life video. The performance tests are taken with several real-life databases, and their results show that the proposed algorithm can efficiently detect abnormally moving objects in real time. The proposed algorithm can be applied to any situation in which abnormal directions or abnormal speeds are detected regardless of direction.

  13. Abnormal grain growth in AISI 304L stainless steel

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

    Shirdel, M., E-mail: mshirdel1989@ut.ac.ir; Mirzadeh, H., E-mail: hmirzadeh@ut.ac.ir; Advanced Metalforming and Thermomechanical Processing Laboratory, School of Metallurgy and Materials Engineering, University of Tehran, Tehran

    2014-11-15

    The microstructural evolution during abnormal grain growth (secondary recrystallization) in 304L stainless steel was studied in a wide range of annealing temperatures and times. At relatively low temperatures, the grain growth mode was identified as normal. However, at homologous temperatures between 0.65 (850 °C) and 0.7 (900 °C), the observed transition in grain growth mode from normal to abnormal, which was also evident from the bimodality in grain size distribution histograms, was detected to be caused by the dissolution/coarsening of carbides. The microstructural features such as dispersed carbides were characterized by optical metallography, X-ray diffraction, scanning electron microscopy, energy dispersivemore » X-ray analysis, and microhardness. Continued annealing to a long time led to the completion of secondary recrystallization and the subsequent reappearance of normal growth mode. Another instance of abnormal grain growth was observed at homologous temperatures higher than 0.8, which may be attributed to the grain boundary faceting/defaceting phenomenon. It was also found that when the size of abnormal grains reached a critical value, their size will not change too much and the grain growth behavior becomes practically stagnant. - Highlights: • Abnormal grain growth (secondary recrystallization) in AISI 304L stainless steel • Exaggerated grain growth due to dissolution/coarsening of carbides • The enrichment of carbide particles by titanium • Abnormal grain growth due to grain boundary faceting at very high temperatures • The stagnancy of abnormal grain growth by annealing beyond a critical time.« less

  14. Centriole overduplication through the concurrent formation of multiple daughter centrioles at single maternal templates.

    PubMed

    Duensing, A; Liu, Y; Perdreau, S A; Kleylein-Sohn, J; Nigg, E A; Duensing, S

    2007-09-20

    Abnormal centrosome numbers are detected in virtually all cancers. The molecular mechanisms that underlie centrosome amplification, however, are poorly characterized. Based on the model that each maternal centriole serves as a template for the formation of one and only one daughter centriole per cell division cycle, the prevailing view is that centriole overduplication arises from successive rounds of centriole reproduction. Here, we provide evidence that a single maternal centriole can concurrently generate multiple daughter centrioles. This mechanism was initially identified in cells treated with the peptide vinyl sulfone proteasome inhibitor Z-L(3)VS. We subsequently found that the formation of more than one daughter at maternal centrioles requires cyclin E/cyclin-dependent kinase 2 as well as Polo-like kinase 4 and that overexpression of these proteins mimics this phenotype in the absence of a proteasome inhibitor. Moreover, we show that the human papillomavirus type 16 E7 oncoprotein stimulates aberrant daughter centriole numbers in part through the formation of more than one daughter centriole at single maternal templates. These results help to explain how oncogenic stimuli can rapidly induce abnormal centriole numbers within a single cell-division cycle and provide insights into the regulation of centriole duplication.

  15. Development of Three-Dimensional Multicellular Tissue-Like Constructs for Mutational Analysis Using Macroporous Microcarriers

    NASA Technical Reports Server (NTRS)

    Jordan, Jacqueline A.; Fraga, Denise N.; Gonda, Steve R.

    2002-01-01

    A three-dimensional (3-D), tissue-like model was developed for the genotoxic assessment of space environment. In previous experiments, we found that culturing mammalian cells in a NASA-designed bioreactor, using Cytodex-3 beads as a scaffold, generated 3-D multicellular spheroids. In an effort to generate scaffold-free spheroids, we developed a new 3-D tissue-like model by coculturing fibroblast and epithelial cell in a NASA bioreactor using macroporous Cultispher-S(TradeMark) microcarriers. Big Blue(Registered Trademark) Rat 2(Lambda) fibroblasts, genetically engineered to contain multiple copies (>60 copies/cell) of the Lac I target gene, were cocultured with radio-sensitive human epithelial cells, H184F5. Over an 8-day period, samples were periodically examined by microscopy and histology to confirm cell attachment, growth, and viability. Immunohistochemistry and western analysis were used to evaluate the expression of specific cytoskeletal and adhesion proteins. Key cell culture parameters (glucose, pH, and lactate concentrations) were monitored daily. Controls were two-dimensional mono layers of fibroblast or epithelial cells cultured in T-flasks. Analysis of 3-D spheroids from the bioreactor suggests fibroblast cells attached to and completely covered the bead surface and inner channels by day 3 in the bioreactor. Treatment of the 3-day spheroids with dispase II dissolved the Cultisphers(TradeMark) and produced multicellular, bead-less constructs. Immunohistochemistry confirmed the presence of vi.mentin, cytokeratin and E-cadherin in treated spheroids. Examination of the dispase II treated spheroids with transmission electron microscopy (TEM) also showed the presence of desmosomes. These results suggest that the controlled enzymatic degradation of an artificial matrix in the low shear environment of the NASA-designed bioreactor can produce 3-D tissue-like spheroids. 2

  16. Quantifying the abnormal hemodynamics of sickle cell anemia

    NASA Astrophysics Data System (ADS)

    Lei, Huan; Karniadakis, George

    2012-02-01

    Sickle red blood cells (SS-RBC) exhibit heterogeneous morphologies and abnormal hemodynamics in deoxygenated states. A multi-scale model for SS-RBC is developed based on the Dissipative Particle Dynamics (DPD) method. Different cell morphologies (sickle, granular, elongated shapes) typically observed in deoxygenated states are constructed and quantified by the Asphericity and Elliptical shape factors. The hemodynamics of SS-RBC suspensions is studied in both shear and pipe flow systems. The flow resistance obtained from both systems exhibits a larger value than the healthy blood flow due to the abnormal cell properties. Moreover, SS-RBCs exhibit abnormal adhesive interactions with both the vessel endothelium cells and the leukocytes. The effect of the abnormal adhesive interactions on the hemodynamics of sickle blood is investigated using the current model. It is found that both the SS-RBC - endothelium and the SS-RBC - leukocytes interactions, can potentially trigger the vicious ``sickling and entrapment'' cycles, resulting in vaso-occlusion phenomena widely observed in micro-circulation experiments.

  17. Musculo-Skeletal Abnormalities in Patients with Marfan Syndrome

    PubMed Central

    Al Kaissi, Ali; Zwettler, Elisabeth; Ganger, Rudolf; Schreiner, Simone; Klaushofer, Klaus; Grill, Franz

    2013-01-01

    Background A leptosomic body type is tall and thin with long hands. Marfanoid features may be familial in nature or pathological, as occurs in congenital contractual arachnodactyly (Beal’s syndrome) and Shprintzen-Goldberg syndrome mimicking some of the changes of Marfan syndrome, although not accompanied by luxation of lens and dissecting aneurysm of aorta. Methods In this article we collected eight patients who were consistent with the diagnosis of Marfan syndrome via phenotypic and genotypic characterization. Results Our patients manifested a constellation of variable presentations of musculo-skeletal abnormalities ranging from developmental dysplasia of the hip, protrusio acetabuli, leg length inequality, patellar instability, scoliosis, to early onset osteoarthritis. Each abnormality has been treated accordingly. Conclusion This is the first paper which includes the diagnosis and the management of the associated musculo-skeletal abnormalities in patients with Marfan syndrome, stressing that patients with Marfan syndrome are exhibiting great variability in the natural history and the severity of musculo-skeletal abnormalities. PMID:23399831

  18. The effect of processing parameters and solid concentration on the mechanical and microstructural properties of freeze-casted macroporous hydroxyapatite scaffolds.

    PubMed

    Farhangdoust, S; Zamanian, A; Yasaei, M; Khorami, M

    2013-01-01

    The design and fabrication of macroporous hydroxyapatite scaffolds, which could overcome current bone tissue engineering limitations, have been considered in recent years. In the current study, controlled unidirectional freeze-casting at different cooling rates was investigated. In the first step, different slurries with initial hydroxyapatite concentrations of 7-37.5 vol.% were prepared. In the next step, different cooling rates from 2 to 14 °C/min were applied to synthesize the porous scaffold. Additionally, a sintering temperature of 1350 °C was chosen as an optimum temperature. Finally, the phase composition (by XRD), microstructure (by SEM), mechanical characteristics, and the porosity of sintered samples were assessed. The porosity of the sintered samples was in a range of 45-87% and the compressive strengths varied from 0.4 MPa to 60 MPa. The mechanical strength of the scaffolds increased as a function of initial concentration, cooling rate, and sintering temperature. With regards to mechanical strength and pore size, the samples with the initial concentration and the cooling rate of 15 vol.% and 5 °C/min, respectively, showed better results. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Separation of vitexin-4″-O-glucoside and vitexin-2″-O-rhamnoside from hawthorn leaves extracts using macroporous resins.

    PubMed

    Li, Hongjuan; Liu, Ying; Jin, Haizhu; Liu, Sujing; Fang, Shengtao; Wang, Chunhua; Xia, Chuanhai

    2015-12-15

    Vitexin-4″-O-glucoside and vitexin-2″-O-rhamnoside are the major flavonoids of hawthorn leaves. In this work, the adsorption and desorption characteristics of vitexin-4″-O-glucoside and vitexin-2″-O-rhamnoside on seven macroporous resins were evaluated. Among the tested resins, the HPD-400 resin showed the best adsorption and desorption capacities. Adsorption isotherms were constructed for the HPD-400 resin and well fitted to Langmuir and Freundlich models. Dynamic adsorption and desorption tests were performed on column packed with the HPD-400 resin to optimize the chromatographic parameters. After one run treatment with the HPD-400 resin, the contents of vitexin-4″-O-glucoside and vitexin-2″-O-rhamnoside in the product were increased 8.44-fold and 8.43-fold from 0.720% and 2.63% to 6.08% and 22.2% with recovery yields of 79.1% and 81.2%, respectively. These results show that the developed method is a promising basis for the large-scale purification of vitexin-4″-O-glucoside and vitexin-2″-O-rhamnoside from hawthorn leaves and other plant materials. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Abnormal Spatial Asymmetry of Selective Attention in ADHD

    ERIC Educational Resources Information Center

    Chan, Edgar; Mattingley, Jason B.; Huang-Pollock, Cynthia; English, Therese; Hester, Robert; Vance, Alasdair; Bellgrove, Mark A.

    2009-01-01

    Background: Evidence for a selective attention abnormality in children with attention deficit hyperactivity disorder (ADHD) has been hard to identify using conventional methods from cognitive science. This study tested whether the presence of selective attention abnormalities in ADHD may vary as a function of perceptual load and target…

  1. Who should be screened for chromosomal abnormalities before ICSI treatment?

    PubMed

    Dul, E C; van Ravenswaaij-Arts, C M A; Groen, H; van Echten-Arends, J; Land, J A

    2010-11-01

    Guidelines on karyotyping infertile men before ICSI treatment are not consistent. Most guidelines recommend chromosomal screening in azoospermic and severe oligozoospermic men, because they are assumed to have the highest risk of abnormalities. We performed a retrospective cohort study in azoospermic men and men eligible for ICSI. We determined the prevalence of chromosomal abnormalities in relation to sperm concentration and compared our data to studies in the literature. A high prevalence of chromosomal abnormalities in azoospermic men was found, but no difference in the prevalence of abnormalities was seen between different sperm concentration categories in non-azoospermic men. This raises the question of who should be screened for chromosomal abnormalities before ICSI treatment. Considering the costs and benefits, we would propose limiting screening to infertile couples with non-obstructive azoospermia.

  2. Abnormal regional cerebral blood flow in childhood autism.

    PubMed

    Ohnishi, T; Matsuda, H; Hashimoto, T; Kunihiro, T; Nishikawa, M; Uema, T; Sasaki, M

    2000-09-01

    Neuroimaging studies of autism have shown abnormalities in the limbic system and cerebellar circuits and additional sites. These findings are not, however, specific or consistent enough to build up a coherent theory of the origin and nature of the brain abnormality in autistic patients. Twenty-three children with infantile autism and 26 non-autistic controls matched for IQ and age were examined using brain-perfusion single photon emission computed tomography with technetium-99m ethyl cysteinate dimer. In autistic subjects, we assessed the relationship between regional cerebral blood flow (rCBF) and symptom profiles. Images were anatomically normalized, and voxel-by-voxel analyses were performed. Decreases in rCBF in autistic patients compared with the control group were identified in the bilateral insula, superior temporal gyri and left prefrontal cortices. Analysis of the correlations between syndrome scores and rCBF revealed that each syndrome was associated with a specific pattern of perfusion in the limbic system and the medial prefrontal cortex. The results confirmed the associations of (i) impairments in communication and social interaction that are thought to be related to deficits in the theory of mind (ToM) with altered perfusion in the medial prefrontal cortex and anterior cingulate gyrus, and (ii) the obsessive desire for sameness with altered perfusion in the right medial temporal lobe. The perfusion abnormalities seem to be related to the cognitive dysfunction observed in autism, such as deficits in ToM, abnormal responses to sensory stimuli, and the obsessive desire for sameness. The perfusion patterns suggest possible locations of abnormalities of brain function underlying abnormal behaviour patterns in autistic individuals.

  3. Incidence of Abnormal Liver Biochemical Tests in Hyperthyroidism

    PubMed Central

    Lin, Tiffany Y.; Shekar, Anshula O.; Li, Ning; Yeh, Michael W.; Saab, Sammy; Wilson, Mark; Leung, Angela M.

    2017-01-01

    Objective Abnormal serum liver function tests are common in patients with untreated thyrotoxicosis, even prior to the initiation of antithyroidal medications that may worsen their severity. There is a wide range of the incidence of these abnormalities in the published literature. The aim of this study was to assess the risks factors and threshold of thyrotoxicosis severity for developing an abnormal liver biochemical test upon the diagnosis of new thyrotoxicosis. Design Single-institution retrospective cohort study. Patients Patients ≥18 years old receiving medical care at a large, academic, urban U.S. medical center between 2002–2016. Measurements Inclusion criteria were a serum thyroid stimulating hormone [TSH] concentration < 0.3 mIU/L or ICD-9 code for thyrotoxicosis, with thyrotoxicosis confirmed by either a concurrent elevated serum triiodothyronine (T3) and/or thyroxine (T4) concentration [total or free] within 3 months), and an available liver biochemical test(s) within 6 months of thyrotoxicosis. The biochemical liver tests assessed were serum aspartate transaminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), gamma-glutamyltransferase (GGT), total bilirubin, and conjugated bilirubin concentrations. Results In this cohort of 1,514 subjects, the overall incidence of any biochemical liver test abnormality within 6 months of thyrotoxicosis was 39%. An initial serum TSH concentration <0.02 mIU/L, male gender, and African-American race were significant predictors of an abnormal serum liver biochemical test within 6 months of the diagnosis of new-onset untreated thyrotoxicosis. Conclusions This study identifies risk factors for patients who develop an abnormal serum liver biochemical test result within 6 months of a diagnosis of untreated thyrotoxicosis. PMID:28199740

  4. How Abnormal Is the Behaviour of Captive, Zoo-Living Chimpanzees?

    PubMed Central

    Birkett, Lucy P.; Newton-Fisher, Nicholas E.

    2011-01-01

    Background Many captive chimpanzees (Pan troglodytes) show a variety of serious behavioural abnormalities, some of which have been considered as possible signs of compromised mental health. The provision of environmental enrichments aimed at reducing the performance of abnormal behaviours is increasing the norm, with the housing of individuals in (semi-)natural social groups thought to be the most successful of these. Only a few quantitative studies of abnormal behaviour have been conducted, however, particularly for the captive population held in zoological collections. Consequently, a clear picture of the level of abnormal behaviour in zoo-living chimpanzees is lacking. Methods We present preliminary findings from a detailed observational study of the behaviour of 40 socially-housed zoo-living chimpanzees from six collections in the United States of America and the United Kingdom. We determined the prevalence, diversity, frequency, and duration of abnormal behaviour from 1200 hours of continuous behavioural data collected by focal animal sampling. Results, Conclusion and Significance Our overall finding was that abnormal behaviour was present in all sampled individuals across six independent groups of zoo-living chimpanzees, despite the differences between these groups in size, composition, housing, etc. We found substantial variation between individuals in the frequency and duration of abnormal behaviour, but all individuals engaged in at least some abnormal behaviour and variation across individuals could not be explained by sex, age, rearing history or background (defined as prior housing conditions). Our data support a conclusion that, while most behaviour of zoo-living chimpanzees is ‘normal’ in that it is typical of their wild counterparts, abnormal behaviour is endemic in this population despite enrichment efforts. We suggest there is an urgent need to understand how the chimpanzee mind copes with captivity, an issue with both scientific and welfare

  5. How abnormal is the behaviour of captive, zoo-living chimpanzees?

    PubMed

    Birkett, Lucy P; Newton-Fisher, Nicholas E

    2011-01-01

    Many captive chimpanzees (Pan troglodytes) show a variety of serious behavioural abnormalities, some of which have been considered as possible signs of compromised mental health. The provision of environmental enrichments aimed at reducing the performance of abnormal behaviours is increasing the norm, with the housing of individuals in (semi-)natural social groups thought to be the most successful of these. Only a few quantitative studies of abnormal behaviour have been conducted, however, particularly for the captive population held in zoological collections. Consequently, a clear picture of the level of abnormal behaviour in zoo-living chimpanzees is lacking. We present preliminary findings from a detailed observational study of the behaviour of 40 socially-housed zoo-living chimpanzees from six collections in the United States of America and the United Kingdom. We determined the prevalence, diversity, frequency, and duration of abnormal behaviour from 1200 hours of continuous behavioural data collected by focal animal sampling. Our overall finding was that abnormal behaviour was present in all sampled individuals across six independent groups of zoo-living chimpanzees, despite the differences between these groups in size, composition, housing, etc. We found substantial variation between individuals in the frequency and duration of abnormal behaviour, but all individuals engaged in at least some abnormal behaviour and variation across individuals could not be explained by sex, age, rearing history or background (defined as prior housing conditions). Our data support a conclusion that, while most behaviour of zoo-living chimpanzees is 'normal' in that it is typical of their wild counterparts, abnormal behaviour is endemic in this population despite enrichment efforts. We suggest there is an urgent need to understand how the chimpanzee mind copes with captivity, an issue with both scientific and welfare implications.

  6. Constitutional abnormalities of chromosome 21 predispose to iAMP21-acute lymphoblastic leukaemia.

    PubMed

    Harrison, Christine J; Schwab, Claire

    2016-03-01

    In addition to Down syndrome, individuals with other constitutional abnormalities of chromosome 21 have an increased risk of developing childhood acute lymphoblastic leukaemia (ALL). Specifically, carriers of the Robertsonian translocation between chromosomes 15 and 21, rob(15;21) (q10; q10)c, have ∼2,700 increased risk of developing ALL with iAMP21 (intrachromosomal amplification of chromosome 21). In these patients, chromosome 15 as well as chromosome 21 is involved in the formation of iAMP21, referred to here as der(21)(15;21). Individuals with constitutional ring chromosomes involving chromosome 21, r(21)c, are also predisposed to iAMP21-ALL, involving the same series of mutational processes as seen in sporadic- and der(21)(15;21)-iAMP21 ALL. Evidence is accumulating that the dicentric nature of the Robertsonian and ring chromosome is the initiating factor in the formation of the complex iAMP21 structure. Unravelling these intriguing predispositions to iAMP21-ALL may provide insight into how other complex rearrangements arise in cancer. Copyright © 2016. Published by Elsevier Masson SAS.

  7. Abnormal interhemispheric connectivity in male psychopathic offenders

    PubMed Central

    Hoppenbrouwers, Sylco S.; De Jesus, Danilo R.; Sun, Yinming; Stirpe, Tania; Hofman, Dennis; McMaster, Jeff; Hughes, Ginny; Daskalakis, Zafiris J.; Schutter, Dennis J.L.G.

    2014-01-01

    Background Psychopathic offenders inevitably violate interpersonal norms and frequently resort to aggressive and criminal behaviour. The affective and cognitive deficits underlying these behaviours have been linked to abnormalities in functional interhemispheric connectivity. However, direct neurophysiological evidence for dysfunctional connectivity in psychopathic offenders is lacking. Methods We used transcranial magnetic stimulation combined with electroencephalography to examine interhemispheric connectivity in the dorsolateral and motor cortex in a sample of psychopathic offenders and healthy controls. We also measured intracortical inhibition and facilitation over the left and right motor cortex to investigate the effects of local cortical processes on interhemispheric connectivity. Results We enrolled 17 psychopathic offenders and 14 controls in our study. Global abnormalities in right to left functional connectivity were observed in psychopathic offenders compared with controls. Furthermore, in contrast to controls, psychopathic offenders showed increased intracortical inhibition in the right, but not the left, hemisphere. Limitations The relatively small sample size limited the sensitivity to show that the abnormalities in interhemispheric connectivity were specifically related to the dorsolateral prefrontal cortex in psychopathic offenders. Conclusion To our knowledge, this study provides the first neurophysiological evidence for abnormal interhemispheric connectivity in psychopathic offenders and may further our understanding of the disruptive antisocial behaviour of these offenders. PMID:23937798

  8. Brain abnormality segmentation based on l1-norm minimization

    NASA Astrophysics Data System (ADS)

    Zeng, Ke; Erus, Guray; Tanwar, Manoj; Davatzikos, Christos

    2014-03-01

    We present a method that uses sparse representations to model the inter-individual variability of healthy anatomy from a limited number of normal medical images. Abnormalities in MR images are then defined as deviations from the normal variation. More precisely, we model an abnormal (pathological) signal y as the superposition of a normal part ~y that can be sparsely represented under an example-based dictionary, and an abnormal part r. Motivated by a dense error correction scheme recently proposed for sparse signal recovery, we use l1- norm minimization to separate ~y and r. We extend the existing framework, which was mainly used on robust face recognition in a discriminative setting, to address challenges of brain image analysis, particularly the high dimensionality and low sample size problem. The dictionary is constructed from local image patches extracted from training images aligned using smooth transformations, together with minor perturbations of those patches. A multi-scale sliding-window scheme is applied to capture anatomical variations ranging from fine and localized to coarser and more global. The statistical significance of the abnormality term r is obtained by comparison to its empirical distribution through cross-validation, and is used to assign an abnormality score to each voxel. In our validation experiments the method is applied for segmenting abnormalities on 2-D slices of FLAIR images, and we obtain segmentation results consistent with the expert-defined masks.

  9. Factors associated with abnormal eating attitudes among Greek adolescents.

    PubMed

    Bilali, Aggeliki; Galanis, Petros; Velonakis, Emmanuel; Katostaras, Theofanis

    2010-01-01

    To estimate the prevalence of abnormal eating attitudes among Greek adolescents and identify possible risk factors associated with these attitudes. Cross-sectional, school-based study. Six randomly selected schools in Patras, southern Greece. The study population consisted of 540 Greek students aged 13-18 years, and the response rate was 97%. The dependent variable was scores on the Eating Attitudes Test-26, with scores > or = 20 indicating abnormal eating attitudes. Bivariate analysis included independent Student t test, chi-square test, and Fisher's exact test. Multivariate logistic regression analysis was applied for the identification of the predictive factors, which were associated independently with abnormal eating attitudes. A 2-sided P value of less than .05 was considered statistically significant. The prevalence of abnormal eating attitudes was 16.7%. Multivariate logistic regression analysis demonstrated that females, urban residents, and those with a body mass index outside normal range, a perception of being overweight, body dissatisfaction, and a family member on a diet were independently related to abnormal eating attitudes. The results indicate that a proportion of Greek adolescents report abnormal eating attitudes and suggest that multiple factors contribute to the development of these attitudes. These findings are useful for further research into this topic and would be valuable in designing preventive interventions. Copyright 2010 Society for Nutrition Education. Published by Elsevier Inc. All rights reserved.

  10. Non-muscle myosin IIB (Myh10) is required for epicardial function and coronary vessel formation during mammalian development

    PubMed Central

    Mitchell, Karen; Al-Anbaki, Ali; Shaikh Qureshi, Wasay Mohiuddin; Tenin, Gennadiy; Lu, Yinhui; Clowes, Christopher; Robertson, Abigail; Barnes, Emma; Wright, Jayne A.; Keavney, Bernard; Lovell, Simon C.

    2017-01-01

    The coronary vasculature is an essential vessel network providing the blood supply to the heart. Disruptions in coronary blood flow contribute to cardiac disease, a major cause of premature death worldwide. The generation of treatments for cardiovascular disease will be aided by a deeper understanding of the developmental processes that underpin coronary vessel formation. From an ENU mutagenesis screen, we have isolated a mouse mutant displaying embryonic hydrocephalus and cardiac defects (EHC). Positional cloning and candidate gene analysis revealed that the EHC phenotype results from a point mutation in a splice donor site of the Myh10 gene, which encodes NMHC IIB. Complementation testing confirmed that the Myh10 mutation causes the EHC phenotype. Characterisation of the EHC cardiac defects revealed abnormalities in myocardial development, consistent with observations from previously generated NMHC IIB null mouse lines. Analysis of the EHC mutant hearts also identified defects in the formation of the coronary vasculature. We attribute the coronary vessel abnormalities to defective epicardial cell function, as the EHC epicardium displays an abnormal cell morphology, reduced capacity to undergo epithelial-mesenchymal transition (EMT), and impaired migration of epicardial-derived cells (EPDCs) into the myocardium. Our studies on the EHC mutant demonstrate a requirement for NMHC IIB in epicardial function and coronary vessel formation, highlighting the importance of this protein in cardiac development and ultimately, embryonic survival. PMID:29084269

  11. Curative effect of neutral macroporous resin hemoperfusion on treating hemodialysis patients with refractory uremic pruritus.

    PubMed

    Li, Wen-Hong; Yin, Yu-Min; Chen, Hao; Wang, Xiao-Dan; Yun, He; Li, Hui; Luo, Jie; Wang, Jin-Wen

    2017-03-01

    This study aims to investigate the efficacy and safety of neutral macroporous resin hemoperfusion in treating maintenance hemodialysis (MHD) patients with refractory uremic pruritus (RUP).Ninety patients were enrolled and were randomly divided into 3 groups: control group, experiment 1 group, and experiment 2 group. Clinical symptom scores of skin itching were recorded before and at 4 and 8 weeks after the treatment. In addition, serum parathyroid hormone (PTH), calcium (Ca), phosphorus (P), and C-reactive protein (CRP) were detected; and the calcium-phosphorus product ([Ca] × [P]) was calculated to compare the curative effect.VSA score, modified Duo pruritus score, and CRP: these indices decreased to some extent at 4 and 8 weeks after treatment in the 2 experiment groups, compared with pretreatment (P < 0.05); and differences among these 3 groups were statistically significant (P < 0.05). PTH, P, and [Ca] × [P]: these indices decreased to some extent at 4 and 8 weeks after treatment in the 2 experiment groups, compared with pretreatment (P < 0.05); and differences between the control and experiment 1 groups, as well as between the control and experiment 2 groups, were statistically significant (P < 0.05). However, the difference between the experiment 1 and experiment 2 groups were not statistically significant (P < 0.05).The effects of HA330 and HA130 resin hemoperfusion apparatus on secondary hyperparathyroidism and the disorder of calcium and phosphorus metabolism are similar. The mechanism may be related to its strong adsorption effect, and its capacity to widely remove inflammatory mediators, immune mediators, and endotoxins.

  12. Curative effect of neutral macroporous resin hemoperfusion on treating hemodialysis patients with refractory uremic pruritus

    PubMed Central

    Li, Wen-Hong; Yin, Yu-Min; Chen, Hao; Wang, Xiao-Dan; Yun, He; Li, Hui; Luo, Jie; Wang, Jin-Wen

    2017-01-01

    Abstract This study aims to investigate the efficacy and safety of neutral macroporous resin hemoperfusion in treating maintenance hemodialysis (MHD) patients with refractory uremic pruritus (RUP). Ninety patients were enrolled and were randomly divided into 3 groups: control group, experiment 1 group, and experiment 2 group. Clinical symptom scores of skin itching were recorded before and at 4 and 8 weeks after the treatment. In addition, serum parathyroid hormone (PTH), calcium (Ca2+), phosphorus (P3+), and C-reactive protein (CRP) were detected; and the calcium–phosphorus product ([Ca] × [P]) was calculated to compare the curative effect. VSA score, modified Duo pruritus score, and CRP: these indices decreased to some extent at 4 and 8 weeks after treatment in the 2 experiment groups, compared with pretreatment (P < 0.05); and differences among these 3 groups were statistically significant (P < 0.05). PTH, P3+, and [Ca] × [P]: these indices decreased to some extent at 4 and 8 weeks after treatment in the 2 experiment groups, compared with pretreatment (P < 0.05); and differences between the control and experiment 1 groups, as well as between the control and experiment 2 groups, were statistically significant (P < 0.05). However, the difference between the experiment 1 and experiment 2 groups were not statistically significant (P < 0.05). The effects of HA330 and HA130 resin hemoperfusion apparatus on secondary hyperparathyroidism and the disorder of calcium and phosphorus metabolism are similar. The mechanism may be related to its strong adsorption effect, and its capacity to widely remove inflammatory mediators, immune mediators, and endotoxins. PMID:28328802

  13. Association of electrocardiogram abnormalities and incident heart failure events.

    PubMed

    Gencer, Baris; Butler, Javed; Bauer, Douglas C; Auer, Reto; Kalogeropoulos, Andreas; Marques-Vidal, Pedro; Applegate, William B; Satterfield, Suzanne; Harris, Tamara; Newman, Anne; Vittinghoff, Eric; Rodondi, Nicolas

    2014-06-01

    Unless effective preventive strategies are implemented, aging of the population will result in a significant worsening of the heart failure (HF) epidemic. Few data exist on whether baseline electrocardiographic (ECG) abnormalities can refine risk prediction for HF. We examined a prospective cohort of 2,915 participants aged 70 to 79 years without preexisting HF, enrolled between April 1997 and June 1998 in the Health, Aging, and Body Composition (Health ABC) study. Minnesota Code was used to define major and minor ECG abnormalities at baseline and at year 4 follow-up. Using Cox models, we assessed (1) the association between ECG abnormalities and incident HF and (2) the incremental value of adding ECG to the Health ABC HF Risk Score using the net reclassification index. At baseline, 380 participants (13.0%) had minor, and 620 (21.3%) had major ECG abnormalities. During a median follow-up of 11.4 years, 485 participants (16.6%) developed incident HF. After adjusting for the Health ABC HF Risk Score variables, the hazard ratio (HR) was 1.27 (95% CI 0.96-1.68) for minor and 1.99 (95% CI 1.61-2.44) for major ECG abnormalities. At year 4, 263 participants developed new and 549 had persistent abnormalities; both were associated with increased subsequent HF risk (HR 1.94, 95% CI 1.38-2.72 for new and HR 2.35, 95% CI 1.82-3.02 for persistent ECG abnormalities). Baseline ECG correctly reclassified 10.5% of patients with HF events, 0.8% of those without HF events, and 1.4% of the overall population. The net reclassification index across the Health ABC HF risk categories was 0.11 (95% CI 0.03-0.19). Among older adults, baseline and new ECG abnormalities are independently associated with increased risk of HF. The contribution of ECG screening for targeted prevention of HF should be evaluated in clinical trials. Copyright © 2014 Mosby, Inc. All rights reserved.

  14. Abnormal uterine bleeding in perimenopause.

    PubMed

    Goldstein, S R; Lumsden, M A

    2017-10-01

    Abnormal uterine bleeding is one of the commonest presenting complaints encountered in a gynecologist's office or primary-care setting. The wider availability of diagnostic tools has allowed prompt diagnosis and treatment of an increasing number of menstrual disorders in an office setting. This White Paper reviews the advantages and disadvantages of transvaginal ultrasound, blind endometrial sampling and diagnostic hysteroscopy. Once a proper diagnosis has been established, appropriate therapy may be embarked upon. Fortunately, only a minority of such patients will have premalignant or malignant disease. When bleeding is sufficient to cause severe anemia or even hypovolemia, prompt intervention is called for. In most of the cases, however, the abnormal uterine bleeding will be disquieting to the patient and significantly affect her 'quality of life'. Sometimes, reassurance and expectant management will be sufficient in such patients. Overall, however, in cases of benign disease, some intervention will be required. The use of oral contraceptive pills especially those with a short hormone-free interval, the insertion of the levonorgestrel intrauterine system, the incorporation of newer medical therapies including antifibrinolytic drugs and selective progesterone receptor modulators and minimally invasive treatments have made outpatient therapy increasingly effective. For others, operative hysteroscopy and endometrial ablation are proven therapeutic tools to provide both long- and short-term relief of abnormal uterine bleeding, thus avoiding, or deferring, hysterectomy.

  15. Novel Precursor-Derived Meso-/Macroporous TiO2/SiOC Nanocomposites with Highly Stable Anatase Nanophase Providing Visible Light Photocatalytic Activity and Superior Adsorption of Organic Dyes

    PubMed Central

    Wasan Awin, Eranezhuth; Lale, Abhijeet; Kumar, Kollamala Chellappan Nair Hari

    2018-01-01

    Titania (TiO2) is considered to have immense potential as a photocatalyst, the anatase phase in particular. There have been numerous attempts to push the limits of its catalytic activity to higher wavelengths to harness the visible electromagnetic radiation. Most of the investigations till date have been restricted to fine-tuning the bandgap by doping, control of defect chemistry at the surface and several to first principle simulations either with limited success or success at the cost of complexities in processing. Here, we report a simple and elegant way of preparing ceramics through precursor chemistry which involves synthesis of macroporous and mesoporous nanocomposites with in situ formation of TiO2 nanocrystals into a robust and protecting SiOC matrix. The in situ nanoscaled TiO2 is anatase of size 9–10 nm, which is uniformly distributed in an amorphous SiOC matrix forming a new generation of nanocomposites that combine the robustness, structural stability and durability of the SiOC matrix while achieving nanoscaled TiO2 functionalities. The stabilization of the anatase phase even at temperature as high as 1200 °C was evident. With an average pore size of 6.8 nm, surface area of 129 m2/g (BET) and pore volume of 0.22 cm3/g (BET), mesoporosity was achieved in the nanocomposites. The composites exhibited visible light photocatalytic activity, which is attributed to the Ti–O–C/TiC bonds resulting in the reduction of band gap by 0.2 to 0.9 eV. Furthermore, the heterojunction formed between the amorphous SiOC and crystalline TiO2 is also expected to minimize the recombination rate of electron-hole pair, making these novel nanocomposites based on TiO2 extremely active in visible wavelength regime. PMID:29494505

  16. Intestinal Rotation Abnormalities and Midgut Volvulus.

    PubMed

    Langer, Jacob C

    2017-02-01

    Rotation abnormalities may be asymptomatic or may be associated with obstruction caused by bands, midgut volvulus, or associated atresia or web. The most important goal of clinicians is to determine whether the patient has midgut volvulus with intestinal ischemia, in which case an emergency laparotomy should be done. If the patient is not acutely ill, the next goal is to determine whether the patient has a narrow-based small bowel mesentery. In general, the outcomes for children with a rotation abnormality are excellent, unless there has been midgut volvulus with significant intestinal ischemia. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Synthesis and Characterization of β-Cyclodextrin Functionalized Ionic Liquid Polymer as a Macroporous Material for the Removal of Phenols and As(V)

    PubMed Central

    Raoov, Muggundha; Mohamad, Sharifah; Abas, Mhd Radzi

    2014-01-01

    β-Cyclodextrin-ionic liquid polymer (CD-ILP) was first synthesized by functionalized β-cyclodextrin (CD) with 1-benzylimidazole (BIM) to form monofunctionalized CD (βCD-BIMOTs) and was further polymerized using a toluene diisocyanate (TDI) linker to form insoluble CD-ILP (βCD-BIMOTs-TDI). The βCD-BIMOTs-TDI polymer was characterized using various tools and the results obtained were compared with those derived from the native β-cyclodextrin polymer (βCD-TDI). The SEM result shows that the presence of ionic liquid (IL) increases the pore size, while the thermo gravimetric analysis (TGA) result shows that the presence of IL increases the stability of the polymer. Meanwhile, Brunauer-Emmett-Teller (BET) results show that βCD-BIMOTs-TDI polymer has 1.254 m2/g surface areas and the Barret-Joyner-Halenda (BJH) pore size distribution result reveals that the polymer exhibits macropores with a pore size of 77.66 nm. Preliminary sorption experiments were carried out and the βCD-BIMOTs-TDI polymer shows enhanced sorption capacity and high removal towards phenols and As(V). PMID:24366065

  18. Interconnectivity of macroporous molecularly imprinted polymers fabricated by hydroxyapatite-stabilized Pickering high internal phase emulsions-hydrogels for the selective recognition of protein.

    PubMed

    Sun, Yanhua; Li, Yuqing; Xu, Jiangfeng; Huang, Ling; Qiu, Tianyun; Zhong, Shian

    2017-07-01

    Hydroxyapatite hybridized molecularly imprinted polydopamine polymers with selective recognition of bovine hemoglobin (BHb) were successfully prepared via Pickering oil-in-water high internal phase emulsions-hydrogels and molecularly imprinting technique. The emulsions were stabilized by hydroxyapatite of which the wettability was modified by 3-methacryloxypropyltrimethoxysilane. The materials were characterized by SEM, IR and TGA. The results showed that the BHb imprinted polymers based on Pickering hydrogels (Hydro-MIPs) possess macropores ranging from 20μm to 50μm, and their large numbers of amino groups and hydroxyl groups result in a favorable adsorption capacity for BHb. The maximum adsorption capacity of Hydro-MIPs for BHb was 438mg/g, 3.27 times more than that of the non-imprinted polymers (Hydro-NIPs). The results indicated that Hydro-MIPs possessing well-defined hierarchical porous structures exhibited outstanding recognition behavior towards the target protein molecules. This work provided a promising alternative method for the fabrication of polymer materials with tunable and interconnected pores structures for the separation and purification of protein in vitro. Copyright © 2017. Published by Elsevier B.V.

  19. The accuracy of ultrasound in the diagnosis of congenital abnormalities.

    PubMed

    Munim, Shama; Nadeem, Salva; Khuwaja, Nadya Ali

    2006-01-01

    To determine the accuracy of ultrasound in the diagnosis of congenital abnormalities at the Aga Khan University Hospital, Karachi. The data of congenital abnormalities was obtained from the obstetrical database and medical records of all cases complicated by congenital abnormalities, delivering from January 2001 to December 2003 and was reviewed. Antenatal ultrasounds had been performed by operators with different level of experience. In addition this data was retrieved from the termination and Congenital anomaly register. A structured data collection form was used to collect information of different variables of interest. Congenital abnormalities, complicated 2.8% (n=170), of all deliveries, including all cases of termination of pregnancy, stillbirth and live births. Out of the total, 11.6% occurred in women above the age of 35 years. Consanguinity was found in 18.2% cases. Prenatal diagnosis was made in just under half of the cases (48.8%). Central nervous system and renal abnormalities were commonly diagnosed. However, facial defects, heart defects or skeletal defects were more commonly missed. Antenatal ultrasound successfully diagnosed foetal abnormalities in 48.8% of cases, and more than 90% Central Nervous system defects and renal abnormalities. In contrast about a quarter of Cardiac defects and none of the facial defects were detected. Based on these findings we recommend that the Sonologist should incorporate four chamber view of the heart and also look at the face carefully.

  20. Down's Syndrome and Leukemia: Mechanism of Additional Chromosomal Abnormalities

    ERIC Educational Resources Information Center

    And Others; Goh, Kong-oo

    1978-01-01

    Chromosomal abnormalities, some appearing in a stepwise clonal evoluation, were found in five Down's syndrome patients (35 weeks to 12 years old), four with acute leukemia and one with abnormal regulation of leukopoiesis. (Author/SBH)

  1. Long memory of abnormal investor attention and the cross-correlations between abnormal investor attention and trading volume, volatility respectively

    NASA Astrophysics Data System (ADS)

    Fan, Xiaoqian; Yuan, Ying; Zhuang, Xintian; Jin, Xiu

    2017-03-01

    Taking Baidu Index as a proxy for abnormal investor attention (AIA), the long memory property in the AIA of Shanghai Stock Exchange (SSE) 50 Index component stocks was empirically investigated using detrended fluctuation analysis (DFA) method. The results show that abnormal investor attention is power-law correlated with Hurst exponents between 0.64 and 0.98. Furthermore, the cross-correlations between abnormal investor attention and trading volume, volatility respectively are studied using detrended cross-correlation analysis (DCCA) and the DCCA cross-correlation coefficient (ρDCCA). The results suggest that there are positive correlations between AIA and trading volume, volatility respectively. In addition, the correlations for trading volume are in general higher than the ones for volatility. By carrying on rescaled range analysis (R/S) and rolling windows analysis, we find that the results mentioned above are effective and significant.

  2. Skin - abnormally dark or light

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003242.htm Abnormally dark or light skin To use the sharing features ... The bronze color can range from light to dark (in fair-skinned people) with the degree of ...

  3. ACR appropriateness criteria(®) on abnormal vaginal bleeding.

    PubMed

    Bennett, Genevieve L; Andreotti, Rochelle F; Lee, Susanna I; Dejesus Allison, Sandra O; Brown, Douglas L; Dubinsky, Theodore; Glanc, Phyllis; Mitchell, Donald G; Podrasky, Ann E; Shipp, Thomas D; Siegel, Cary Lynn; Wong-You-Cheong, Jade J; Zelop, Carolyn M

    2011-07-01

    In evaluating a woman with abnormal vaginal bleeding, imaging cannot replace definitive histologic diagnosis but often plays an important role in screening, characterization of structural abnormalities, and directing appropriate patient care. Transvaginal ultrasound (TVUS) is generally the initial imaging modality of choice, with endometrial thickness a well-established predictor of endometrial disease in postmenopausal women. Endometrial thickness measurements of ≤5 mm and ≤4 mm have been advocated as appropriate upper threshold values to reasonably exclude endometrial carcinoma in postmenopausal women with vaginal bleeding; however, the best upper threshold endometrial thickness in the asymptomatic postmenopausal patient remains a subject of debate. Endometrial thickness in a premenopausal patient is a less reliable indicator of endometrial pathology since this may vary widely depending on the phase of menstrual cycle, and an upper threshold value for normal has not been well-established. Transabdominal ultrasound is generally an adjunct to TVUS and is most helpful when TVUS is not feasible or there is poor visualization of the endometrium. Hysterosonography may also allow for better delineation of both the endometrium and focal abnormalities in the endometrial cavity, leading to hysteroscopically directed biopsy or resection. Color and pulsed Doppler may provide additional characterization of a focal endometrial abnormality by demonstrating vascularity. MRI may also serve as an important problem-solving tool if the endometrium cannot be visualized on TVUS and hysterosonography is not possible, as well as for pretreatment planning of patients with suspected endometrial carcinoma. CT is generally not warranted for the evaluation of patients with abnormal bleeding, and an abnormal endometrium incidentally detected on CT should be further evaluated with TVUS. Copyright © 2011 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  4. The agreement between self-reported cervical smear abnormalities and screening programme records.

    PubMed

    Canfell, Karen; Beral, Valerie; Green, Jane; Cameron, Rebecca; Baker, Krys; Brown, Anna

    2006-01-01

    The Million Women Study is a cohort study of women aged 50-64 years in England and Scotland. As a component of the follow-up questionnaire, participants were asked to indicate if they had an abnormal cervical smear in the previous five years. This study compared self-reported cervical abnormalities with screening records obtained from the National Health Service Cervical Screening Programme. For 1944 randomly selected Million Women Study participants in Oxfordshire, screening records were assessed over a six-year period prior to the date of self-reporting. The six-year period was chosen to allow for errors in the recall of timing of abnormal smears. A total of 68 women (3.5%) had a record of at least one equivocal or abnormal smear within the last six years, whereas 49 women (2.5%) self-reported an abnormality. There was a strong trend for an increased probability of self-reporting a history of an abnormal smear as the severity of the recorded abnormality increased (P <0.001). For women with an NHS record of borderline dyskaryosis, mild dyskaryosis, or moderate dyskaryosis/severe dyskaryosis/invasive cancer, the proportions reporting an abnormality were 40%, 58% and 77%, respectively. For women with negative and inadequate smears, the proportion self-reporting an abnormality were 0.6% and 0.7%, respectively. These results indicate that among women whose screening programme records show an abnormal smear, the proportion self-reporting an abnormality increases with the severity of the recorded lesion. Almost all women with a record of negative or inadequate smear(s) correctly interpret the result and do not self-report an abnormality.

  5. Electrophysiological abnormalities associated with extensive myelinated retinal nerve fibers.

    PubMed

    Tay, Su Ann; Sanjay, Srinivasan

    2012-07-01

    An observational case report of electrophysiological abnormalities in a patient with anisomyopic amblyopia as a result of unilateral extensive myelinated retinal nerve fibers (MNFs) is illustrated. The electrophysiological readings revealed an abnormal pattern electroretinogram (PERG) but normal full-field electroretinogram readings in the affected eye. The visual-evoked potential was also undetectable in that eye. Our findings suggest that extensive MNFs can be associated with electrophysiological abnormalities, in particular the PERG, which can aid in diagnosing the cause of impaired vision when associated with amblyopia.

  6. Electrophysiological abnormalities associated with extensive myelinated retinal nerve fibers

    PubMed Central

    Tay, Su Ann; Sanjay, Srinivasan

    2012-01-01

    An observational case report of electrophysiological abnormalities in a patient with anisomyopic amblyopia as a result of unilateral extensive myelinated retinal nerve fibers (MNFs) is illustrated. The electrophysiological readings revealed an abnormal pattern electroretinogram (PERG) but normal full-field electroretinogram readings in the affected eye. The visual-evoked potential was also undetectable in that eye. Our findings suggest that extensive MNFs can be associated with electrophysiological abnormalities, in particular the PERG, which can aid in diagnosing the cause of impaired vision when associated with amblyopia. PMID:22824610

  7. Gains in accuracy from averaging ratings of abnormality

    NASA Astrophysics Data System (ADS)

    Swensson, Richard G.; King, Jill L.; Gur, David; Good, Walter F.

    1999-05-01

    Six radiologists used continuous scales to rate 529 chest-film cases for likelihood of five separate types of abnormalities (interstitial disease, nodules, pneumothorax, alveolar infiltrates and rib fractures) in each of six replicated readings, yielding 36 separate ratings of each case for the five abnormalities. Analyses for each type of abnormality estimated the relative gains in accuracy (area below the ROC curve) obtained by averaging the case-ratings across: (1) six independent replications by each reader (30% gain), (2) six different readers within each replication (39% gain) or (3) all 36 readings (58% gain). Although accuracy differed among both readers and abnormalities, ROC curves for the median ratings showed similar relative gains in accuracy. From a latent-variable model for these gains, we estimate that about 51% of a reader's total decision variance consisted of random (within-reader) errors that were uncorrelated between replications, another 14% came from that reader's consistent (but idiosyncratic) responses to different cases, and only about 35% could be attributed to systematic variations among the sampled cases that were consistent across different readers.

  8. Simultaneous separation and purification of flavonoids and oleuropein from Olea europaea L. (olive) leaves using macroporous resin.

    PubMed

    Li, Chen; Zheng, Yuanyuan; Wang, Xiaofei; Feng, Shilan; Di, Duolong

    2011-12-01

    This study developed a feasible process to simultaneously separate and purify polyphenols, including flavonoids and oleuropein, from the leaves of Olea europaea L. Macroporous resins were used as the separation and purification materials. The performance and separation capabilities of eight resins (D101, DM130, HPD450, LSA-21, LSA-40, 07C, LSD001 and HPD600) were systematically evaluated. The contents of target polyphenols in different extracts were determined using ultraviolet (for flavonoids) and high-performance liquid chromatographic (for oleuropein) methods. The static adsorption and desorption results showed that resin LSA-21 had better adsorption properties among the eight resins. Influential factors such as extraction method, pH value of feeding solution, desorption solution, adsorption kinetics and adsorption isotherm, etc. to the extraction and purification of these polyphenols were successively investigated on resin LSA-21. The target flavonoids and oleuropein were selectively purified using resin LSA-21. Compared with the contents in raw leaves, the contents of total flavonoids and oleuropein in the final purified products were increased 13.2-fold (from 16 to 211 g kg(-1) ) and 7.5-fold (from 120 to 902 g kg(-1) ) with recovery yields of 87.9% and 85.6%, respectively. This extraction and purification method could be used in the large-scale enrichment or purification of flavonoids, oleuropein and other polyphenols from O. europaea L. leaves or other herbal materials in industrial, food processing and medical manufacture. Copyright © 2011 Society of Chemical Industry.

  9. Endocrine Abnormalities in Patients with Chronic Kidney Disease.

    PubMed

    Kuczera, Piotr; Adamczak, Marcin; Wiecek, Andrzej

    2015-01-01

    In patients with chronic kidney disease the alterations of the endocrine system may arise from several causes. The kidney is the site of degradation as well as synthesis of many different hormones. Moreover, a number of concomitant pathological conditions such as inflammation, metabolic acidosis and malnutrition may participate in the pathogenesis of endocrine abnormalities in this group of patients. The most pronounced endocrine abnormalities in patients with chronic kidney disease are the deficiencies of: calcitriol, testosterone, insulin-like growth factor and, erythropoietin (EPO). Additionally accumulation of several hormones, such as: prolactin, growth hormone and insulin frequently also occur. The clinical consequences of the abovementioned endocrine abnormalities are among others: anemia, infertility and bone diseases.

  10. NEW FRONTIER IN UNDERSTANDING THE MECHANISMS OF DEVELOPMENTAL ABNORMALITIES

    EPA Science Inventory

    Recent advancements in molecular developmental biology afford an opportunity to apply newly developed tools for understanding the mechanisms of both normal and abnormal development. lthough a number of agents have been identified as causing developmental abnormalities, knowledge ...

  11. Clinical Correlation between Perverted Nystagmus and Brain MRI Abnormal Findings

    PubMed Central

    Han, Won-Gue; Yoon, Hee-Chul; Kim, Tae-Min; Rah, Yoon Chan

    2016-01-01

    Background and Objectives To analyze the clinical correlation between perverted nystagmus and brain magnetic resonance imaging (MRI) abnormal findings and to evaluate whether perverted nystagmus is clinically significant results of brain abnormal lesions or not. Subjects and Methods We performed medical charts review from January 2008 to July 2014, retrospectively. Patients who were suspected central originated vertigo at Frenzel goggles test were included among patients who visited our hospital. To investigate the correlation with nystagmus suspected central originated vertigo and brain MRI abnormal findings, we confirmed whether performing brain MRI or not. Then we exclude that patients not performed brain MRI. Results The number of patients with perverted nystagmus was 15, upbeating was 1 and down-beating was 14. Among these patients, 5 patients have brain MRI abnormal findings. However, 2 patients with MRI abnormal findings were not associated correctly with perverted nystagmus and only 3 patients with perverted nystagmus were considered central originated vertigo and further evaluation and treatment was performed by the department of neurology. Conclusions Perverted nystagmus was considered to the abnormalities at brain lesions, especially cerebellum, but neurologic symptoms and further evaluation were needed for exact diagnosis of central originated vertigo. PMID:27626081

  12. Syringomyelia and Craniocervical Junction Abnormalities in Chihuahuas.

    PubMed

    Kiviranta, A-M; Rusbridge, C; Laitinen-Vapaavuori, O; Hielm-Björkman, A; Lappalainen, A K; Knowler, S P; Jokinen, T S

    2017-11-01

    Chiari-like malformation (CM) and syringomyelia (SM) are widely reported in Cavalier King Charles Spaniels and Griffon Bruxellois dogs. Increasing evidence indicates that CM and SM also occur in other small and toy breed dogs, such as Chihuahuas. To describe the presence of SM and craniocervical junction (CCJ) abnormalities in Chihuahuas and to evaluate the possible association of CCJ abnormalities with SM. To describe CM/SM-related clinical signs and neurologic deficits and to investigate the association of CM/SM-related clinical signs with signalment, SM, or CCJ abnormalities. Fifty-three client-owned Chihuahuas. Prospective study. Questionnaire analyses and physical and neurologic examinations were obtained before magnetic resonance and computed tomography imaging. Images were evaluated for the presence of SM, CM, and atlantooccipital overlapping. Additionally, medullary kinking, dorsal spinal cord compression, and their sum indices were calculated. Scratching was the most common CM/SM-related clinical sign and decreased postural reaction the most common neurologic deficit in 73 and 87% of dogs, respectively. Chiari-like malformation and SM were present in 100 and 38% of dogs, respectively. Syringomyelia was associated with the presence of CM/SM-related clinical signs (P = 0.034), and medullary kinking and sum indices were higher in dogs with clinical signs (P = 0.016 and P = 0.007, respectively). Syringomyelia and CCJ abnormalities are prevalent in Chihuahuas. Syringomyelia was an important factor for the presence of CM/SM-related clinical signs, but many dogs suffered from similar clinical signs without being affected by SM, highlighting the clinical importance of CCJ abnormalities in Chihuahuas. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  13. Convergent evidence for abnormal striatal synaptic plasticity in dystonia

    PubMed Central

    Peterson, David A.; Sejnowski, Terrence J.; Poizner, Howard

    2010-01-01

    Dystonia is a functionally disabling movement disorder characterized by abnormal movements and postures. Although substantial recent progress has been made in identifying genetic factors, the pathophysiology of the disease remains a mystery. A provocative suggestion gaining broader acceptance is that some aspect of neural plasticity may be abnormal. There is also evidence that, at least in some forms of dystonia, sensorimotor “use” may be a contributing factor. Most empirical evidence of abnormal plasticity in dystonia comes from measures of sensorimotor cortical organization and physiology. However, the basal ganglia also play a critical role in sensorimotor function. Furthermore, the basal ganglia are prominently implicated in traditional models of dystonia, are the primary targets of stereotactic neurosurgical interventions, and provide a neural substrate for sensorimotor learning influenced by neuromodulators. Our working hypothesis is that abnormal plasticity in the basal ganglia is a critical link between the etiology and pathophysiology of dystonia. In this review we set up the background for this hypothesis by integrating a large body of disparate indirect evidence that dystonia may involve abnormalities in synaptic plasticity in the striatum. After reviewing evidence implicating the striatum in dystonia, we focus on the influence of two neuromodulatory systems: dopamine and acetylcholine. For both of these neuromodulators, we first describe the evidence for abnormalities in dystonia and then the means by which it may influence striatal synaptic plasticity. Collectively, the evidence suggests that many different forms of dystonia may involve abnormal plasticity in the striatum. An improved understanding of these altered plastic processes would help inform our understanding of the pathophysiology of dystonia, and, given the role of the striatum in sensorimotor learning, provide a principled basis for designing therapies aimed at the dynamic processes

  14. The effectiveness of airline pilot training for abnormal events.

    PubMed

    Casner, Stephen M; Geven, Richard W; Williams, Kent T

    2013-06-01

    To evaluate the effectiveness of airline pilot training for abnormal in-flight events. Numerous accident reports describe situations in which pilots responded to abnormal events in ways that were different from what they had practiced many times before. One explanation for these missteps is that training and testing for these skills have become a highly predictable routine for pilots who arrive to the training environment well aware of what to expect. Under these circumstances, pilots get plentiful practice in responding to abnormal events but may get little practice in recognizing them and deciding which responses to offer. We presented 18 airline pilots with three abnormal events that are required during periodic training and testing. Pilots were presented with each event under the familiar circumstances used during training and also under less predictable circumstances as they might occur during flight. When presented in the routine ways seen during training, pilots gave appropriate responses and showed little variability. However, when the abnormal events were presented unexpectedly, pilots' responses were less appropriate and showed great variability from pilot to pilot. The results suggest that the training and testing practices used in airline training may result in rote-memorized skills that are specific to the training situation and that offer modest generalizability to other situations. We recommend a more complete treatment of abnormal events that allows pilots to practice recognizing the event and choosing and recalling the appropriate response. The results will aid the improvement of existing airline training practices.

  15. Structural control in the synthesis of inorganic porous materials

    NASA Astrophysics Data System (ADS)

    Holland, Brian Thomas

    Mesoporous (2.0--50.0 nm pore diameter) and macroporous (50.0 nm on up) materials have been the basis of my studies. These materials, for many years, possessed large pore size distributions. Recently, however, it has been possible to synthesize both mesoporous and macroporous materials that possess highly ordered uniform pores throughout the material. Workers at Mobil Corporation in 1992 discovered a hexagonally arrayed mesoporous material, designated MCM-41, which exhibited uniform pores ranging from 2.0--10.0 nm in diameter. In my work MCM-41 was used as a host for the incorporation of meso-tetrakis(5-trimethylammoniumpentyl)porphyrin (TMAP-Cl) and as a model for the synthesis of mesoporous alumino- and galloaluminophosphates which were created using cluster precursors of the type MO4Al 12(OH)24(H2O)12 7+, M = Al or Ga. Macroporous materials with uniform pore sizes have been synthesized by our group with frameworks consisting of a variety of metal oxides, metals, organosilanes, aluminophosphates and bimodal pores. These materials are synthesized from the addition of metal precursors to preordered polystyrene spheres. Removal of the spheres results in the formation of macropores with highly uniform pores extending microns in length. Porous materials with uniform and adjustable pore sizes in the mesoporous and macroporous size regimes offer distinct advantages over non-ordered materials for numerous reasons. First, catalysis reactions that are based on the ability of the porous materials to impose size and shape restrictions on the substrate are of considerable interest in the petroleum and petrochemical industries. As pore diameters increase larger molecules can be incorporated into the pores, i.e., biological molecules, dyes, etc. For the macroporous materials synthesized by our group it has been envisioned that these structures may not only be used for catalysis because of increased efficiencies of flow but for more advanced applications, e.g., photonic crystals

  16. Histopathological pattern of abnormal uterine bleeding in endometrial biopsies.

    PubMed

    Vaidya, S; Lakhey, M; Vaidya, S; Sharma, P K; Hirachand, S; Lama, S; KC, S

    2013-03-01

    Abnormal uterine bleeding is a common presenting complaint in gyanecology out patient department. Histopathological evaluation of the endometrial samples plays a significant role in the diagnosis of abnormal uterine bleeding. This study was carried out to determine the histopathological pattern of the endometrium in women of various age groups presenting with abnormal uterine bleeding. Endometrial biopsies and curettings of patients presenting with abnormal uterine bleeding was retrospectively studied. A total of 403 endometrial biopsies and curettings were analyzed. The age of the patients ranged from 18 to 70 years. Normal cyclical endometrium was seen in 165 (40.94%) cases, followed by 54 (13.40%) cases of disordered proliferative endometrium and 44 (10.92%) cases of hyperplasia. Malignancy was seen in 10 (2.48%) cases. Hyperplasia and malignancy were more common in the perimenopausal and postmenopausal age groups. Histopathological examination of endometrial biopsies and curettings in patients presenting with abnormal uterine bleeding showed a wide spectrum of changes ranging from normal endometrium to malignancy. Endometrial evaluation is specially recommended in women of perimenopausal and postmenopausal age groups presenting with AUB, to rule out a possibility of any preneoplastic condition or malignancy.

  17. Adverse Pregnancy Outcomes after Abnormal First Trimester Screening for Aneuploidy

    PubMed Central

    Goetzl, Laura

    2010-01-01

    Women with abnormal first trimester screening but with a normal karyotype are at risk for adverse pregnancy outcomes. A nuchal translucency >3.5mm is associated with an increased risk of subsequent pregnancy loss, fetal infection, fetal heart abnormalities and other structural abnormalities. Abnormal first trimester analytes are also associated with adverse pregnancy outcomes but the predictive value is less impressive. As a single marker, PAPP-A <1st%ile has a good predictive value for subsequent fetal growth restriction. Women with PAPP-A<5th%ile should undergo subsequent risk assessment with routine MSAFP screening with the possible addition of uterine artery PI assessment in the midtrimester. PMID:20638576

  18. Sporadic adult onset dystonia: sensory abnormalities as an endophenotype in unaffected relatives

    PubMed Central

    Walsh, Richard; O'Dwyer, John P; Sheikh, Ifthikar H; O'Riordan, Sean; Lynch, Tim; Hutchinson, Michael

    2007-01-01

    Background Most patients with adult onset primary torsion dystonia (AOPTD) have the sporadic form of the disease. They may however be the only manifesting family members of a poorly penetrant genetic disorder. Sensory changes, including structural abnormalities of the primary sensory cortex, are found in AOPTD. Spatial discrimination threshold (SDT), a measure of sensory cortical organisation, is abnormal in AOPTD and in unaffected relatives of patients with familial AOPTD. Our hypothesis was that abnormal SDTs might be found in unaffected relatives of patients with sporadic AOPTD. Methods SDTs were assessed at the index finger bilaterally by a grating orientation task. Normal age related SDTs were derived from 141 control subjects aged 20–64 years. SDTs were considered abnormal when greater than 2.5 SD above the control mean. In total, 105 of 171 (61%) eligible unaffected siblings and offspring of patients with cervical dystonia had SDT examined. Results Fourteen of 48 siblings (29%) and 10 of 57 (18%) offspring were found to have an abnormal SDT. Only five of the 20 patients examined had abnormal SDTs. In 11 of the 25 families, no abnormality was found in an unaffected relative. In the 14 families where at least one unaffected relative had an abnormal SDT, 14 of 37 siblings (38%) and 10 of 33 offspring (30%) had abnormal SDTs. Conclusion Sensory abnormalities found in unaffected relatives of patients with apparently sporadic AOPTD may be a surrogate marker for the carriage of an abnormal gene. PMID:17702779

  19. The handicap of abnormal colour vision.

    PubMed

    Cole, Barry L

    2004-07-01

    All people with abnormal colour vision, except for a few mildly affected deuteranomals, report that they experience problems with colour in everyday life and at work. Contemporary society presents them with increasing problems because colour is now so widely used in printed materials and in computer displays. Equal opportunity law gives them protection against unfair discrimination in employment, so a decision to exclude a person from employment on the grounds of abnormal colour vision must now be well supported by good evidence and sound argument. This paper reviews the investigations that have contributed to understanding the nature and consequences of the problems they have. All those with abnormal colour vision are at a disadvantage with comparative colour tasks that involve precise matching of colours or discrimination of fine colour differences either because of their loss of colour discrimination or anomalous perception of metamers. The majority have problems when colour is used to code information, in man-made colour codes and in naturally occurring colour codes that signal ripeness of fruit, freshness of meat or illness. They can be denied the benefit of colour to mark out objects and organise complex visual displays. They may be unreliable when a colour name is used as an identifier. They are slower and less successful in search when colour is an attribute of the target object or is used to organise the visual display. Because those with the more severe forms of abnormal colour vision perceive a very limited gamut of colours, they are at a disadvantage in the pursuit and appreciation of those forms of art that use colour.

  20. Transvaginal Ultrasound for the Diagnosis of Abnormal Uterine Bleeding.

    PubMed

    Wheeler, Karen C; Goldstein, Steven R

    2017-03-01

    Transvaginal ultrasound is the first-line imaging test for the evaluation of abnormal uterine bleeding in both premenopausal and postmenopausal women. Transvaginal ultrasound can be used to diagnose structural causes of abnormal bleeding such as polyps, adenomyosis, leiomyomas, hyperplasia, and malignancy, and can also be beneficial in making the diagnosis of ovulatory dysfunction. Traditional 2-dimensional imaging is often enhanced by the addition of 3-dimension imaging with coronal reconstruction and saline infusion sonohysterography. In this article we discuss specific ultrasound findings and technical considerations useful in the diagnosis of abnormal uterine bleeding.

  1. [Hysteroscopy clinic: diagnostic and therapeutic method in abnormal uterine bleeding].

    PubMed

    Alanis Fuentes, José; Obregón Zegarra, Eva Haydee

    2012-12-01

    Abnormal uterine bleeding is a public health problem prevalence exceeded only by abnormal vaginal discharge as a reason for medical consultation. To describe the findings reported by the Hysteroscopy clinic of the Hospital GEA Gonzalez on patients with Abnormal Uterine bleeding diagnosis. Retrospective, transversal, descriptive study. The total 2546 records of those patient that were evaluated by Office Hysteroscopic between January 2007 and December 2008 on the Hysteroscopy Clinic of Hospital Manuel GEA Gonzalez, then we selected the 1482 records of those patients that were sended because of an Abnormal Uterine bleeding condition. We descrive the frequencies of the diagnosis and its interrelation with the age of the patients. We also report the therapeutical interventions during office hysteroscopy. The mean age of the patients was 42.15 +/- 9.30 years (from 12 a 92 years); the age groups of patients that belonged to 40-44 years and 45-49 years are the most frequent patient and they represent the 25% y el 23.3% of the records. The abnormal findings occurred on the 66% de of the patients. Those patients of 65 years old and older do not have any report of normal cavities, all of then have abnormal findings. The leiomyoma (26.9%) and the endometrial polyps (27.3%) were the most frequent findings. The postmenopausal bleeding had a rate of 90.9% abnormal findings and in this group of patients the most frequent diagnosis was atrophic endometrium (32.2%) and polyps (24.3%). Besides that the office hysteroscopy show its therapeutical usefulness because of the 67% and 77.5% of polipectomy perform for endometrial and cervical polyps respectively The office Hysteroscopy is a well tolerated diagnosis and therapeutic method that is useful for any women with abnormal uterine bleeding condition and it is the ideal technique for the examination of abnormal uterine bleeding in postmenopausal women... The office hysteroscopy is a efficient cost-effective and cost-benefic method for

  2. Craniofacial abnormalities among patients with Edwards Syndrome

    PubMed Central

    Rosa, Rafael Fabiano M.; Rosa, Rosana Cardoso M.; Lorenzen, Marina Boff; Zen, Paulo Ricardo G.; Graziadio, Carla; Paskulin, Giorgio Adriano

    2013-01-01

    OBJECTIVE To determine the frequency and types of craniofacial abnormalities observed in patients with trisomy 18 or Edwards syndrome (ES). METHODS This descriptive and retrospective study of a case series included all patients diagnosed with ES in a Clinical Genetics Service of a reference hospital in Southern Brazil from 1975 to 2008. The results of the karyotypic analysis, along with clinical data, were collected from medical records. RESULTS: The sample consisted of 50 patients, of which 66% were female. The median age at first evaluation was 14 days. Regarding the karyotypes, full trisomy of chromosome 18 was the main alteration (90%). Mosaicism was observed in 10%. The main craniofacial abnormalities were: microretrognathia (76%), abnormalities of the ear helix/dysplastic ears (70%), prominent occiput (52%), posteriorly rotated (46%) and low set ears (44%), and short palpebral fissures/blepharophimosis (46%). Other uncommon - but relevant - abnormalities included: microtia (18%), orofacial clefts (12%), preauricular tags (10%), facial palsy (4%), encephalocele (4%), absence of external auditory canal (2%) and asymmetric face (2%). One patient had an initial suspicion of oculo-auriculo-vertebral spectrum (OAVS) or Goldenhar syndrome. CONCLUSIONS: Despite the literature description of a characteristic clinical presentation for ES, craniofacial alterations may be variable among these patients. The OAVS findings in this sample are noteworthy. The association of ES with OAVS has been reported once in the literature. PMID:24142310

  3. Are ECG abnormalities in Noonan syndrome characteristic for the syndrome?

    PubMed

    Raaijmakers, R; Noordam, C; Noonan, J A; Croonen, E A; van der Burgt, C J A M; Draaisma, J M T

    2008-12-01

    Of all patients with Noonan syndrome, 50-90% have one or more congenital heart defects. The most frequent occurring are pulmonary stenosis (PS) and hypertrophic cardiomyopathy. The electrocardiogram (ECG) of a patient with Noonan syndrome often shows a characteristic pattern, with a left axis deviation, abnormal R/S ratio over the left precordium, and an abnormal Q wave. The objective of this study was to determine if these ECG characteristics are an independent feature of the Noonan syndrome or if they are related to the congenital heart defect. A cohort study was performed with 118 patients from two university hospitals in the United States and in The Netherlands. All patients were diagnosed with definite Noonan syndrome and had had an ECG and echocardiography. Sixty-nine patients (58%) had characteristic abnormalities of the ECG. In the patient group without a cardiac defect (n = 21), ten patients had a characteristic ECG abnormality. There was no statistical relationship between the presence of a characteristic ECG abnormality and the presence of a cardiac defect (p = 0.33). Patients with hypertrophic cardiomyopathy had more ECG abnormalities in total (p = 0.05), without correlation with a specific ECG abnormality. We conclude that the ECG features in patients with Noonan syndrome are characteristic for the syndrome and are not related to a specific cardiac defect. An ECG is very useful in the diagnosis of Noonan syndrome; every child with a Noonan phenotype should have an ECG and echocardiogram for evaluation.

  4. Radiographic abnormalities among construction workers exposed to quartz containing dust

    PubMed Central

    Tjoe, N; Burdorf, A; Parker, J; Attfield, M; van Duivenbooden, C; Heederik, D

    2003-01-01

    Background: Construction workers are exposed to quartz containing respirable dust, at levels that may cause fibrosis in the lungs. Studies so far have not established a dose-response relation for radiographic abnormalities for this occupational group. Aims: To measure the extent of radiographic abnormalities among construction workers primarily exposed to quartz containing respirable dust. Methods: A cross sectional study on radiographic abnormalities indicative of pneumoconiosis was conducted among 1339 construction workers mainly involved in grinding, (jack)-hammering, drilling, cutting, sawing, and polishing. Radiological abnormalities were determined by median results of the 1980 International Labour Organisation system of three certified "B" readers. Questionnaires were used for assessment of occupational history, presence of respiratory diseases, and symptoms and smoking habits. Results: An abnormality of ILO profusion category 1/0 and greater was observed on 10.2% of the chest radiographs, and profusion category of 1/1 or greater on 2.9% of the radiographs. The average duration of exposure of this group was 19 years and the average age was 42. The predominant type of small opacities (irregularly shaped) is presumably indicative of mixed dust pneumoconiosis. The prevalence of early signs of nodular silicosis (small rounded opacities of category 1/0 or greater) was low (0.8%). Conclusions: The study suggests an elevated risk of radiographic abnormalities among these workers with expected high exposure. An association between radiographic abnormalities and cumulative exposure to quartz containing dust from construction sites was observed, after correction for potentially confounding variables. PMID:12771392

  5. Hemorheological abnormalities in human arterial hypertension

    NASA Astrophysics Data System (ADS)

    Lo Presti, Rosalia; Hopps, Eugenia; Caimi, Gregorio

    2014-05-01

    Blood rheology is impaired in hypertensive patients. The alteration involves blood and plasma viscosity, and the erythrocyte behaviour is often abnormal. The hemorheological pattern appears to be related to some pathophysiological mechanisms of hypertension and to organ damage, in particular left ventricular hypertrophy and myocardial ischemia. Abnormalities have been observed in erythrocyte membrane fluidity, explored by fluorescence spectroscopy and electron spin resonance. This may be relevant for red cell flow in microvessels and oxygen delivery to tissues. Although blood viscosity is not a direct target of antihypertensive therapy, the rheological properties of blood play a role in the pathophysiology of arterial hypertension and its vascular complications.

  6. Congenital abnormalities associated with extrahepatic portal hypertension.

    PubMed Central

    Odièvre, M; Pigé, G; Alagille, D

    1977-01-01

    Congenital abnormalities were present in 12 out of 30 (40%) children with extrahepatic portal hypertension of unknown cause, but in only 2 out of 17 (12%) children with extnahepatic portal hypertension secondary to umbilical vein catheterization or omphalitis. The most frequent abnormalities in this series and in published reports were atrial septal defect, malformation of the biliary tract, and anomalous inferior vena cava. These findings are consistent with the view that some cases with extrahepatic portal hypertension are congenital in origin. PMID:869567

  7. Abnormal uterine bleeding in reproductive-aged women.

    PubMed

    Matthews, Michelle L

    2015-03-01

    Abnormal uterine bleeding is a common medical condition with several causes. The International Federation of Gynecology and Obstetrics published guidelines in 2011 to develop universally accepted nomenclature and a classification system. In addition, the American College of Obstetrics and Gynecology recently updated recommendations on evaluation of abnormal uterine bleeding and indications for endometrial biopsies. This article reviews both medical and surgical treatments, including meta-analysis reviews of the most effective treatment options. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. An abattoir survey of equine dental abnormalities in Queensland, Australia.

    PubMed

    Chinkangsadarn, T; Wilson, G J; Greer, R M; Pollitt, C C; Bird, P S

    2015-06-01

    A cadaver study to estimate the prevalence of dental disorders in horses presented at an abattoir in Queensland, Australia. Cadaver heads at a Queensland abattoir were examined for the presence of dental abnormalities and categorised into age groups. The prevalence of abnormalities was analysed by binomial observation of observed proportion, Pearson's Chi-square test or Fisher's exact correlation test. Strength of association was evaluated using Cramer's V test. Heads from horses (n=400) estimated to be between 1 and 30 years of age were placed into four age groups. The most common abnormalities were sharp enamel points (55.3%) and hooks (43%). The highest frequency of dental diseases and abnormalities were in horses 11-15 years old (97.5%). Common abnormalities were found in all groups and the prevalence increased with age. This study suggests that all horses should have regular complete dental examinations to detect and treat dental disorders in order to limit more severe dental pathologies later in life. © 2015 Australian Veterinary Association.

  9. Novel morphology changes from 3D ordered macroporous structure to V2O5 nanofiber grassland and its application in electrochromism

    PubMed Central

    Tong, Zhongqiu; Lv, Haiming; Zhang, Xiang; Yang, Haowei; Tian, Yanlong; Li, Na; Zhao, Jiupeng; Li, Yao

    2015-01-01

    Because vanadium pentoxide (V2O5) is the only oxide that shows both anodic and cathodic coloration electrochromism, the reversible lithium ion insertion/extraction processes in V2O5 lead to not only reversible optical parameter changes but also multicolor changes for esthetics. Because of the outstanding electrochemical properties of V2O5 nanofibers, they show great potential to enhance V2O5 electrochromism. However, the development and practical application of V2O5 nanofibers are still lacking, because traditional preparation approaches have several drawbacks, such as multiple processing steps, unsatisfactory electrical contact with the substrate, expensive equipment, and rigorous experimental conditions. Herein, we first report a novel and convenient strategy to prepare grass-like nanofiber-stacked V2O5 films by a simple annealing treatment of an amorphous, three-dimensionally ordered macroporous vanadia film. The V2O5 nanofiber grassland exhibits promising transmittance modulation, fast switching responses, and high color contrast because of the outstanding electrochemical properties of V2O5 nanofibers as well as the high Li-ion diffusion coefficients and good electrical contact with the substrate. Moreover, the morphology transformation mechanism is investigated in detail. PMID:26578383

  10. Volume estimation of brain abnormalities in MRI data

    NASA Astrophysics Data System (ADS)

    Suprijadi, Pratama, S. H.; Haryanto, F.

    2014-02-01

    The abnormality of brain tissue always becomes a crucial issue in medical field. This medical condition can be recognized through segmentation of certain region from medical images obtained from MRI dataset. Image processing is one of computational methods which very helpful to analyze the MRI data. In this study, combination of segmentation and rendering image were used to isolate tumor and stroke. Two methods of thresholding were employed to segment the abnormality occurrence, followed by filtering to reduce non-abnormality area. Each MRI image is labeled and then used for volume estimations of tumor and stroke-attacked area. The algorithms are shown to be successful in isolating tumor and stroke in MRI images, based on thresholding parameter and stated detection accuracy.

  11. Fetal Alcohol Spectrum Disorders and Abnormal Neuronal Plasticity

    PubMed Central

    Medina, Alexandre E.

    2012-01-01

    The ingestion of alcohol during pregnancy can result in a group of neurobehavioral abnormalities collectively known as fetal alcohol spectrum disorders (FASD). During the past decade, studies using animal models indicated that early alcohol exposure can dramatically affect neuronal plasticity, an essential property of the central nervous system responsible for the normal wiring of the brain and involved in processes such as learning and memory. The abnormalities in neuronal plasticity caused by alcohol can explain many of the neurobehavioral deficits observed in FASD. Conversely, improving neuronal plasticity may have important therapeutic benefits. In this review, the author discuss the mechanisms that lead to these abnormalities and comment on recent pharmacological approaches that have been showing promising results in improving neuronal plasticity in FASD. PMID:21383101

  12. Abnormal cholesterol is associated with prefrontal white matter abnormalities among obese adults, a diffusion tensor imaging study

    PubMed Central

    Cohen, Jessica I.; Cazettes, Fanny; Convit, Antonio

    2011-01-01

    The brain is the most cholesterol-rich organ in the body. Although most of the cholesterol in the brain is produced endogenously, some studies suggest that systemic cholesterol may be able to enter the brain. We investigated whether abnormal cholesterol profiles correlated with diffusion-tensor-imaging-based estimates of white matter microstructural integrity of lean and overweight/obese (o/o) adults. Twenty-two lean and 39 obese adults underwent magnetic resonance imaging, kept a 3-day food diary, and had a standardized assessment of fasting blood lipids. The lean group ate less cholesterol rich food than o/o although both groups ate equivalent servings of food per day. Voxelwise correlational analyses controlling for age, diabetes, and white matter hyperintensities, resulted in two significant clusters of negative associations between abnormal cholesterol profile and fractional anisotropy, located in the left and right prefrontal lobes. When the groups were split, the lean subjects showed no associations, whereas the o/o group expanded the association to three significant clusters, still in the frontal lobes. These findings suggest that cholesterol profile abnormalities may explain some of the reductions in white matter microstructural integrity that are reported in obesity. PMID:22163070

  13. 42 CFR 37.53 - Notification of abnormal roentgenographic findings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... suggesting, enlarged heart, tuberculosis, lung cancer, or any other significant abnormal findings other than... files and the most recent examination was interpreted to show enlarged heart, tuberculosis, cancer... findings suggesting, abnormality of cardiac shape or size, tuberculosis, lung cancer, or any other...

  14. XYY chromosome abnormality in sexual homicide perpetrators.

    PubMed

    Briken, Peer; Habermann, Niels; Berner, Wolfgang; Hill, Andreas

    2006-03-05

    In a retrospective investigation of the court reports about sexual homicide perpetrators chromosome analysis had been carried out in 13 of 166 (7.8%) men. Three men (1.8%) with XYY chromosome abnormality were found. This rate is much higher than that found in unselected samples of prisoners (0.7-0.9%) or in the general population (0.01%). The three men had shown prepubescent abnormalities, school problems, and had suffered from physical abuse. The chromosome analysis in all cases had been carried out in connection with the forensic psychiatric court report due to the sexual homicide. However, two men had earlier psychiatric referrals. All were diagnosed as sexual sadistic, showed a psychopathic syndrome or psychopathy according to the Psychopathy Checklist-Revised [Hare RD, 1991, The Hare Psychopathy Checklist-Revised, Toronto, Ontario, Canada: Multi-Health Systems]. Two were multiple murderers. Especially forensic psychiatrists should be vigilant of the possibility of XYY chromosome abnormalities in sexual offenders. (c) 2006 Wiley-Liss, Inc.

  15. Prediction of vascular abnormalities on CT angiography in patients with acute headache.

    PubMed

    Alons, Imanda M E; Goudsmit, Ben F J; Jellema, Korné; van Walderveen, Marianne A A; Wermer, Marieke J H; Algra, Ale

    2018-05-09

    Patients with acute headache increasingly undergo CT-angiography (CTA) to evaluate underlying vascular causes. The aim of this study is to determine clinical and non-contrast CT (NCCT) criteria to select patients who might benefit from CTA. We retrospectively included patients with acute headache who presented to the emergency department of an academic medical center and large regional teaching hospital and underwent NCCT and CTA. We identified factors that increased the probability of finding a vascular abnormality on CTA, performed multivariable regression analyses and determined discrimination with the c-statistic. A total of 384 patients underwent NCCT and CTA due to acute headache. NCCT was abnormal in 194 patients. Among these, we found abnormalities in 116 cases of which 99 aneurysms. In the remaining 190 with normal NCCT we found abnormalities in 12 cases; four unruptured aneurysms, three cerebral venous thrombosis', two reversible cerebral vasoconstriction syndromes, two cervical arterial dissections and one cerebellar infarction. In multivariable analysis abnormal NCCT, lowered consciousness and presentation within 6 hr of headache onset were independently associated with abnormal CTA. The c-statistic of abnormal NCCT alone was 0.80 (95% CI: 0.75-0.80), that also including the other two variables was 0.84 (95% CI: 0.80-0.88). If NCCT was normal no other factors could help identify patients at risk for abnormalities. In patients with acute headache abnormal NCCT is the strongest predictor of a vascular abnormality on CTA. If NCCT is normal no other predictors increase the probability of finding an abnormality on CTA and diagnostic yield is low. © 2018 The Authors. Brain and Behavior published by Wiley Periodicals, Inc.

  16. [Congenital abnormalities of the aorta in children and adolescents].

    PubMed

    Eichhorn, J G; Ley, S

    2007-11-01

    Aortic abnormalities are common cardiovascular malformations accounting for 15-20% of all congenital heart disease. Ultrafast CT and MR imaging are noninvasive, accurate and robust techniques that can be used in the diagnosis of aortic malformations. While their sensitivity in detecting vascular abnormalities seems to be as good as that of conventional catheter angiocardiography, at over 90%, they are superior in the diagnosis of potentially life-threatening complications, such as tracheal, bronchial, or esophageal compression. It has been shown that more than 80% of small children with aortic abnormalities benefit directly from the use of noninvasive imaging: either cardiac catheterization is no longer necessary or radiation doses and periods of general anesthesia for interventional catheterization procedures can be much reduced. The most important congenital abnormalities of the aorta in children and adolescents are presented with reference to examples, and the value of CT and MR angiography is documented.

  17. Streptozotocin induced oxidative stress, innate immune system responses and behavioral abnormalities in male mice.

    PubMed

    Amiri, Shayan; Haj-Mirzaian, Arya; Momeny, Majid; Amini-Khoei, Hossein; Rahimi-Balaei, Maryam; Poursaman, Simin; Rastegar, Mojgan; Nikoui, Vahid; Mokhtari, Tahmineh; Ghazi-Khansari, Mahmoud; Hosseini, Mir-Jamal

    2017-01-06

    Recent evidence indicates the involvement of inflammatory factors and mitochondrial dysfunction in the etiology of psychiatric disorders such as anxiety and depression. To investigate the possible role of mitochondrial-induced sterile inflammation in the co-occurrence of anxiety and depression, in this study, we treated adult male mice with the intracerebroventricular (i.c.v.) infusion of a single low dose of streptozotocin (STZ, 0.2mg/mouse). Using valid and qualified behavioral tests for the assessment of depressive and anxiety-like behaviors, we showed that STZ-treated mice exhibited behaviors relevant to anxiety and depression 24h following STZ treatment. We observed that the co-occurrence of anxiety and depressive-like behaviors in animals were associated with abnormal mitochondrial function, nitric oxide overproduction and, the increased activity of cytosolic phospholipase A 2 (cPLA 2 ) in the hippocampus. Further, STZ-treated mice had a significant upregulation of genes associated with the innate immune system such as toll-like receptors 2 and 4. Pathological evaluations showed no sign of neurodegeneration in the hippocampus of STZ-treated mice. Results of this study revealed that behavioral abnormalities provoked by STZ, as a cytotoxic agent that targets mitochondria and energy metabolism, are associated with abnormal mitochondrial activity and, consequently the initiation of innate-inflammatory responses in the hippocampus. Our findings highlight the role of mitochondria and innate immunity in the formation of sterile inflammation and behaviors relevant to anxiety and depression. Also, we have shown that STZ injection (i.c.v.) might be an animal model for depression and anxiety disorders based on sterile inflammation. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  18. Limited evidence of abnormal intra-colonic pressure profiles in diverticular disease - a systematic review.

    PubMed

    Jaung, R; Robertson, J; O'Grady, G; Milne, T; Rowbotham, D; Bissett, I P

    2017-06-01

    Abnormal colonic pressure profiles and high intraluminal pressures are postulated to contribute to the formation of sigmoid colon diverticulosis and the pathophysiology of diverticular disease. This study aimed to review evidence for abnormal colonic pressure profiles in diverticulosis. All published studies investigating colonic pressure in patients with diverticulosis were searched in three databases (Medline, Embase, Scopus). No language restrictions were applied. Any manometry studies in which patients with diverticulosis were compared with controls were included. The Newcastle-Ottawa Quality Assessment Scale (NOS) for case-control studies was used as a measure of risk of bias. A cut-off of five or more points on the NOS (fair quality in terms of risk of bias) was chosen for inclusion in the meta-analysis. Ten studies (published 1962-2005) met the inclusion criteria. The studies followed a wide variety of protocols and all used low-resolution manometry (sensor spacing range 7.5-15 cm). Six studies compared intra-sigmoid pressure, with five of six showing higher pressure in diverticulosis vs controls, but only two reached statistical significance. A meta-analysis was not performed as only two studies were above the cut-off and these did not have comparable outcomes. This systematic review of manometry data shows that evidence for abnormal pressure in the sigmoid colon in patients with diverticulosis is weak. Existing studies utilized inconsistent methodology, showed heterogeneous results and are of limited quality. Higher quality studies using modern manometric techniques and standardized reporting methods are needed to clarify the role of colonic pressure in diverticulosis. Colorectal Disease © 2017 The Association of Coloproctology of Great Britain and Ireland.

  19. Neurologic Correlates of Gait Abnormalities in Cerebral Palsy: Implications for Treatment

    PubMed Central

    Zhou, Joanne; Butler, Erin E.; Rose, Jessica

    2017-01-01

    Cerebral palsy (CP) is the most common movement disorder in children. A diagnosis of CP is often made based on abnormal muscle tone or posture, a delay in reaching motor milestones, or the presence of gait abnormalities in young children. Neuroimaging of high-risk neonates and of children diagnosed with CP have identified patterns of neurologic injury associated with CP, however, the neural underpinnings of common gait abnormalities remain largely uncharacterized. Here, we review the nature of the brain injury in CP, as well as the neuromuscular deficits and subsequent gait abnormalities common among children with CP. We first discuss brain injury in terms of mechanism, pattern, and time of injury during the prenatal, perinatal, or postnatal period in preterm and term-born children. Second, we outline neuromuscular deficits of CP with a focus on spastic CP, characterized by muscle weakness, shortened muscle-tendon unit, spasticity, and impaired selective motor control, on both a microscopic and functional level. Third, we examine the influence of neuromuscular deficits on gait abnormalities in CP, while considering emerging information on neural correlates of gait abnormalities and the implications for strategic treatment. This review of the neural basis of gait abnormalities in CP discusses what is known about links between the location and extent of brain injury and the type and severity of CP, in relation to the associated neuromuscular deficits, and subsequent gait abnormalities. Targeted treatment opportunities are identified that may improve functional outcomes for children with CP. By providing this context on the neural basis of gait abnormalities in CP, we hope to highlight areas of further research that can reduce the long-term, debilitating effects of CP. PMID:28367118

  20. Preferential flow dynamics in agricultural soils in Navarre (Spain): an experimental approach to gain insight into water connectivity

    NASA Astrophysics Data System (ADS)

    Iturria, Iban; Zubieta, Elena; Giménez, Rafael; Ángel Campo-Bescós, Miguel

    2017-04-01

    To address studies on soil erosion and water quality it is essential to understand and quantify water movements through the soil. The estimation of this movement is usually based on soil texture and structure since it is assumed that the water moves across soil matrix. However, soils prone to the formation of cracks or macropores could trigger rapid flow paths, capable of drastically changing the movement of the water and, therefore, its connectivity across the soil. This would have important consequences both for runoff -and thus for erosion- and for groundwater quality. Local preliminary studies have shown that in many agrarian soils in Navarre (Spain), infiltration rate was mainly determined by this type of preferential flow. On the other hand, the formation of these cracks basically responded to expansion/contraction processes of clays due to changes in soil moisture content caused by rainfall. The aim of this work was to quantify in agricultural soil the presence of cracks/macropores responsible for preferential flow and their temporal variation compared to different soil moisture contents. The work was carried out in experimental plots (150 m2) of the UPNA with different type of conventional tillage: (i) mouldboard plough: (ii) chisel and (iii) mouldboard+Molon rake. Each plot was divided into two halves or subplots. On half was submitted to the action of 4 simulated rainfall (5 days passing between each event); whereas in the other half, no rain was applied. Six subplots were thus defined. After each of the 4 rainfall, and once the 5 days had passed, the following experiments were conducted in each of the 6 subplots. In microplots (0.5 m2) a colourant (aqueous solution of bromide) was applied (Lu and Wu, 2003). To be specific, 8 mm of this solution was applied as intense rain with a sprinkler, but avoiding any waterlogging. Then, vertical cuts of 50-60 cm were made where the cracks/macropores were evidenced by the colourant. Photographs of the profiles were

  1. ABNORMAL POLLEN VACUOLATION1 (APV1) is required for male fertility by contributing to anther cuticle and pollen exine formation in maize.

    PubMed

    Somaratne, Yamuna; Tian, Youhui; Zhang, Hua; Wang, Mingming; Huo, Yanqing; Cao, Fengge; Zhao, Li; Chen, Huabang

    2017-04-01

    Anther cuticle and pollen exine are the major protective barriers against various stresses. The proper functioning of genes expressed in the tapetum is vital for the development of pollen exine and anther cuticle. In this study, we report a tapetum-specific gene, Abnormal Pollen Vacuolation1 (APV1), in maize that affects anther cuticle and pollen exine formation. The apv1 mutant was completely male sterile. Its microspores were swollen, less vacuolated, with a flat and empty anther locule. In the mutant, the anther epidermal surface was smooth, shiny, and plate-shaped compared with the three-dimensional crowded ridges and randomly formed wax crystals on the epidermal surface of the wild-type. The wild-type mature pollen had elaborate exine patterning, whereas the apv1 pollen surface was smooth. Only a few unevenly distributed Ubisch bodies were formed on the apv1 mutant, leading to a more apparent inner surface. A significant reduction in the cutin monomers was observed in the mutant. APV1 encodes a member of the P450 subfamily, CYP703A2-Zm, which contains 530 amino acids. APV1 appeared to be widely expressed in the tapetum at the vacuolation stage, and its protein signal co-localized with the endoplasmic reticulum (ER) signal. RNA-Seq data revealed that most of the genes in the fatty acid metabolism pathway were differentially expressed in the apv1 mutant. Altogether, we suggest that APV1 functions in the fatty acid hydroxylation pathway which is involved in forming sporopollenin precursors and cutin monomers that are essential for the development of pollen exine and anther cuticle in maize. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  2. Nuclei pulposi formation from the embryonic notochord occurs normally in GDF5-deficient mice

    PubMed Central

    Maier, Jennifer A.; Harfe, Brian D.

    2011-01-01

    Study Design The transition of the mouse embryonic notochord into nuclei pulposi was determined (“fate mapped”) in vivo in GDF-5 null mice using the Shhcre and R26R alleles. Objective To determine if abnormal nuclei pulposi formation from the embryonic notochord was responsible for defects present in adult nuclei pulposi of Gdf-5 null mice. Summary of Background Data The development, maintenance, and degeneration of the intervertebral disc are not understood. Previously, we demonstrated that all cells in the adult nucleus pulposus of normal mice are derived from the embryonic notochord. Gdf-5 null mice have been reported to contain intervertebral discs in which the nucleus pulposus is abnormal. It is currently unclear if disc defects in Gdf-5 null mice arise during the formation of nuclei pulposi from the notochord during embryogenesis or resulted from progressive postnatal degeneration of nuclei pulposi. Methods Gdf-5 mRNA expression was examined in the discs of wild-type embryos by RNA in situ hybridization to determine when and where this gene was expressed. To examine nucleus pulposus formation in Gdf-5 null mice, intervertebral discs in which embryonic notochord cells were marked were analyzed in newborn and 24 week old mice. Results Our Gdf-5 mRNA in situ experiments determined that this gene is localized to the annulus fibrosus and not the nucleus pulposus in mouse embryos. Notochord fate mapping experiments revealed that notochord cells in Gdf-5 null mice correctly form nuclei pulposi. Conclusion Our data suggest that the defects reported in the nucleus pulposus of adult Gdf-5 null mice do not result from abnormal patterning of the embryonic notochord. The use of mouse alleles to mark cells that produce all cell types that reside in the adult nucleus pulposus will allow for a detailed examination of disc formation in other mouse mutants that have been reported to contain disc defects. PMID:21278629

  3. IFT25, an intraflagellar transporter protein dispensable for ciliogenesis in somatic cells, is essential for sperm flagella formation.

    PubMed

    Liu, Hong; Li, Wei; Zhang, Yong; Zhang, Zhengang; Shang, Xuejun; Zhang, Ling; Zhang, Shiyang; Li, Yanwei; Somoza, Andres V; Delpi, Brandon; Gerton, George L; Foster, James A; Hess, Rex A; Pazour, Gregory J; Zhang, Zhibing

    2017-05-01

    Intraflagellar transport (IFT) is a conserved mechanism essential for the assembly and maintenance of most eukaryotic cilia and flagella. However, IFT25, a component of the IFT complex, is not required for the formation of cilia in somatic tissues. In mice, the gene is highly expressed in the testis, and its expression is upregulated during the final phase when sperm flagella are formed. To investigate the role of IFT25 in sperm flagella formation, the gene was specifically disrupted in male germ cells. All homozygous knockout mice survived to adulthood and did not show any gross abnormalities. However, all homozygous knockout males were completely infertile. Sperm numbers were reduced and these sperm were completely immotile. Multiple morphological abnormalities were observed in sperm, including round heads, short and bent tails, with some tails showing branched flagella and others with frequent abnormal thicknesses, as well as swollen tips of the tail. Transmission electron microscopy revealed that flagellar accessory structures, including the fibrous sheath and outer dense fibers, were disorganized, and most sperm had also lost the "9+2" microtubule structure. In the testis, IFT25 forms a complex with other IFT proteins. In Ift25 knockout testes, IFT27, an IFT25 binding partner, was missing, and IFT20 and IFT81 levels were also reduced. Our findings suggest that IFT25, although not necessary for the formation of cilia in somatic cells, is indispensable for sperm flagellum formation and male fertility in mice. © The Authors 2017. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please journals.permissions@oup.com.

  4. Abnormal Neural Progenitor Cells Differentiated from Induced Pluripotent Stem Cells Partially Mimicked Development of TSC2 Neurological Abnormalities.

    PubMed

    Li, Yaqin; Cao, Jiqing; Chen, Menglong; Li, Jing; Sun, Yiming; Zhang, Yu; Zhu, Yuling; Wang, Liang; Zhang, Cheng

    2017-04-11

    Tuberous sclerosis complex (TSC) is a disease featuring devastating and therapeutically challenging neurological abnormalities. However, there is a lack of specific neural progenitor cell models for TSC. Here, the pathology of TSC was studied using primitive neural stem cells (pNSCs) from a patient presenting a c.1444-2A>C mutation in TSC2. We found that TSC2 pNSCs had higher proliferative activity and increased PAX6 expression compared with those of control pNSCs. Neurons differentiated from TSC2 pNSCs showed enlargement of the soma, perturbed neurite outgrowth, and abnormal connections among cells. TSC2 astrocytes had increased saturation density and higher proliferative activity. Moreover, the activity of the mTOR pathway was enhanced in pNSCs and induced in neurons and astrocytes. Thus, our results suggested that TSC2 heterozygosity caused neurological malformations in pNSCs, indicating that its heterozygosity might be sufficient for the development of neurological abnormalities in patients. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  5. Pediatric Patients Discharged from the Emergency Department with Abnormal Vital Signs.

    PubMed

    Winter, Josephine; Waxman, Michael J; Waterman, George; Ata, Ashar; Frisch, Adam; Collins, Kevin P; King, Christopher

    2017-08-01

    Children often present to the emergency department (ED) with minor conditions such as fever and have persistently abnormal vital signs. We hypothesized that a significant portion of children discharged from the ED would have abnormal vital signs and that those discharged with abnormal vital signs would experience very few adverse events. We performed a retrospective chart review encompassing a 44-month period of all pediatric patients (aged two months to 17 years) who were discharged from the ED with an abnormal pulse rate, respiratory rate, temperature, or oxygen saturation. We used a local quality assurance database to identify pre-defined adverse events after discharge in this population. Our primary aim was to determine the proportion of children discharged with abnormal vital signs and the frequency and nature of adverse events. Additionally, we performed a sub-analysis comparing the rate of adverse events in children discharged with normal vs. abnormal vital signs, as well as a standardized review of the nature of each adverse event. Of 33,185 children discharged during the study period, 5,540 (17%) of these patients had at least one abnormal vital sign. There were 24/5,540 (0.43%) adverse events in the children with at least one abnormal vital sign vs. 47/27,645 (0.17%) adverse events in the children with normal vital signs [relative risk = 2.5 (95% confidence interval, 1.6 to 2.4)].However, upon review of each adverse event we found only one case that was related to the index visit, was potentially preventable by a 23-hour hospital observation, and caused permanent disability. In our study population, 17% of the children were discharged with at least one abnormal vital sign, and there were very few adverse (0.43%) events associated with this practice. Heart rate was the most common abnormal vital sign leading to an adverse event. Severe adverse events that were potentially related to the abnormal vital sign(s) were exceedingly rare. Additional research is

  6. Managing abnormal eating behaviours in frontotemporal lobar degeneration patients with topiramate.

    PubMed

    Shinagawa, Shunichiro; Tsuno, Norifumi; Nakayama, Kazuhiko

    2013-03-01

    Abnormal eating behaviours are specific to frontotemporal lobar degeneration and increase caregiver burden. Topiramate, an anticonvulsant, suppresses cravings for alcohol and other substances and is a potential treatment for binge eating. However, there are few reports on topiramate efficacy for abnormal eating behaviours in frontotemporal lobar degeneration patients. We present three Japanese frontotemporal lobar degeneration patients with abnormal eating behaviours. Topiramate was effective, especially for compulsive eating, in cases with distinct lobar atrophy, but not for all abnormal eating behaviours. © 2013 The Authors. Psychogeriatrics © 2013 Japanese Psychogeriatric Society.

  7. Axonal abnormalities in vanishing white matter.

    PubMed

    Klok, Melanie D; Bugiani, Marianna; de Vries, Sharon I; Gerritsen, Wouter; Breur, Marjolein; van der Sluis, Sophie; Heine, Vivi M; Kole, Maarten H P; Baron, Wia; van der Knaap, Marjo S

    2018-04-01

    We aimed to study the occurrence and development of axonal pathology and the influence of astrocytes in vanishing white matter. Axons and myelin were analyzed using electron microscopy and immunohistochemistry on Eif2b4 and Eif2b5 single- and double-mutant mice and patient brain tissue. In addition, astrocyte-forebrain co-culture studies were performed. In the corpus callosum of Eif2b5- mutant mice, myelin sheath thickness, axonal diameter, and G-ratio developed normally up to 4 months. At 7 months, however, axons had become thinner, while in control mice axonal diameters had increased further. Myelin sheath thickness remained close to normal, resulting in an abnormally low G-ratio in Eif2b5- mutant mice. In more severely affected Eif2b4-Eif2b5 double-mutants, similar abnormalities were already present at 4 months, while in milder affected Eif2b4 mutants, few abnormalities were observed at 7 months. Additionally, from 2 months onward an increased percentage of thin, unmyelinated axons and increased axonal density were present in Eif2b5 -mutant mice. Co-cultures showed that Eif2b5 mutant astrocytes induced increased axonal density, also in control forebrain tissue, and that control astrocytes induced normal axonal density, also in mutant forebrain tissue. In vanishing white matter patient brains, axons and myelin sheaths were thinner than normal in moderately and severely affected white matter. In mutant mice and patients, signs of axonal transport defects and cytoskeletal abnormalities were minimal. In vanishing white matter, axons are initially normal and atrophy later. Astrocytes are central in this process. If therapy becomes available, axonal pathology may be prevented with early intervention.

  8. Varenicline and Abnormal Sleep Related Events

    PubMed Central

    Savage, Ruth L.; Zekarias, Alem; Caduff-Janosa, Pia

    2015-01-01

    Study Objectives: To assess adverse drug reaction reports of “abnormal sleep related events” associated with varenicline, a partial agonist to the α4β2 subtype of nicotinic acetylcholine receptors on neurones, indicated for smoking cessation. Design: Twenty-seven reports of “abnormal sleep related events” often associated with abnormal dreams, nightmares, or somnambulism, which are known to be associated with varenicline use, were identified in the World Health Organisation (WHO) Global Individual Case Safety Reports Database. Original anonymous reports were obtained from the four national pharmacovigilance centers that submitted these reports and assessed for reaction description and causality. Measurements and Results: These 27 reports include 10 of aggressive activity occurring during sleep and seven of other sleep related harmful or potentially harmful activities, such as apparently deliberate self-harm, moving a child or a car, or lighting a stove or a cigarette. Assessment of these 17 reports of aggression or other actual or potential harm showed that nine patients recovered or were recovering on varenicline withdrawal and there were no consistent alternative explanations. Thirteen patients experienced single events, and two had multiple events. Frequency was not stated for the remaining two patients. Conclusions: The descriptions of the reports of aggression during sleep with violent dreaming are similar to those of rapid eye movement sleep behavior disorder and also nonrapid eye movement (NREM) sleep parasomnias in some adults. Patients who experience somnambulism or dreams of a violent nature while taking varenicline should be advised to consult their health providers. Consideration should be given to clarifying the term sleep disorders in varenicline product information and including sleep related harmful and potentially harmful events. Citation: Savage RL, Zekarias A, Caduff-Janosa P. Varenicline and abnormal sleep related events. SLEEP 2015

  9. Abnormal centromere-chromatid apposition (ACCA) and Peters' anomaly.

    PubMed

    Wertelecki, W; Dev, V G; Superneau, D W

    1985-08-01

    Abnormal centromere-chromatid apposition (ACCA) was noted in a patient with Peters' anomaly. Previous reports of ACCA emphasized its association with tetraphocomelia and other congenital malformations (Roberts, SC Phocomelia, Pseudothalidomide Syndromes). This report expands the array of congenital malformations associated with ACCA and emphasizes the diagnostic importance of ocular defects for the ascertainment of additional cases of ACCA and its possible relationship with abnormal cell division.

  10. Identification of a novel Lymantria dispar nucleopolyhedrovirus mutant that exhibits abnormal polyhedron formation and virion occlusion.

    PubMed

    Slavicek, J M; Mercer, M J; Pohlman, D; Kelly, M E; Bischoff, D S

    1998-07-01

    In previous studies on the formation of Lymantria dispar nuclear polyhedrosis virus (LdMNPV) few polyhedra (FP) mutants, several polyhedron formation mutants (PFM) were identified that appeared to be unique. These viral mutants are being characterized to investigate the processes of polyhedron formation and virion occlusion. LdMNPV isolate PFM-1 is one of these mutants, and is described in this report. Genetic techniques were used to determine if isolate PFM-1 contained a mutation in the polyhedrin or 25K FP gene. Wild-type viruses were recovered after coinfection of Ld652Y cells with isolate PFM-1 and a FP mutant, and with isolates PFM-1 and PFM-C (isolate PFM-C contains a mutation in the polyhedrin gene). These viruses were analyzed by genomic restriction endonuclease digestion and found to be chimeras of the original PFMs used in the coinfections. Marker rescue studies mapped the mutation in isolate PFM-1 to a genomic region that does not include the polyhedrin or 25K FP genes. Isolate PFM-1 produced approximately 14-fold fewer polyhedra than LdMNPV isolate A21-MPV, an isolate that produces wild-type levels of polyhedra, and approximately 2-fold more polyhedra compared to the FP isolate 122-2. Polyhedra generated by isolate PFM-1 were normal in size and shape but contained very few viral nucleocapsids. The same amount of budded virus (BV) was released from cells infected with isolates PFM-1 and A21-MPV. In contrast, isolate 122-2 yielded significantly more BV than isolates PFM-1 and A21-MPV.

  11. Important property of polymer spheres for the preparation of three-dimensionally ordered macroporous (3DOM) metal oxides by the ethylene glycol method: the glass-transition temperature.

    PubMed

    Sadakane, Masahiro; Sasaki, Keisuke; Nakamura, Hiroki; Yamamoto, Takashi; Ninomiya, Wataru; Ueda, Wataru

    2012-12-21

    We demonstrate that the glass-transition temperature (T(g)) of a polymer sphere template is a crucial factor in the production of three-dimensionally ordered macroporous (3DOM) materials. Metal nitrate dissolved in ethylene glycol-methanol was infiltrated into the void of a face-centered, close-packed colloidal crystal of poly(methyl methacrylate) (PMMA)-based spheres. The metal nitrate reacts with EG to form a metal oxalate (or metal glycoxylate) solid (nitrate oxidation) in the void of the template when the metal nitrate-EG-PMMA composite is heated. Further heating converts metal oxalate to metal oxide and removes PMMA to form 3DOM materials. We investigated the effect of T(g) of PMMA templates and obtained clear evidence that the solidification temperature of the metal precursor solution (i.e., nitration oxidation temperature) should be lower than the T(g) of the polymer spheres to obtain a well-ordered 3DOM structure.

  12. Angiogenesis in calcium phosphate scaffolds by inorganic copper ion release.

    PubMed

    Barralet, Jake; Gbureck, Uwe; Habibovic, Pamela; Vorndran, Elke; Gerard, Catherine; Doillon, Charles J

    2009-07-01

    Angiogenesis in a tissue-engineered device may be induced by incorporating growth factors (e.g., vascular endothelial growth factor [VEGF]), genetically modified cells, and=or vascular cells. It represents an important process during the formation and repair of tissue and is essential for nourishment and supply of reparative and immunological cells. Inorganic angiogenic factors, such as copper ions, are therefore of interest in the fields of regenerative medicine and tissue engineering due to their low cost, higher stability, and potentially greater safety compared with recombinant proteins or genetic engineering approaches. The purpose of this study was to compare tissue responses to 3D printed macroporous bioceramic scaffolds implanted in mice that had been loaded with either VEGF or copper sulfate. These factors were spatially localized at the end of a single macropore some 7 mm from the surface of the scaffold. Controls without angiogenic factors exhibited only poor tissue growth within the blocks; in contrast, low doses of copper sulfate led to the formation of microvessels oriented along the macropore axis. Further, wound tissue ingrowth was particularly sensitive to the quantity of copper sulfate and was enhanced at specific concentrations or in combination with VEGF. The potential to accelerate and guide angiogenesis and wound healing by copper ion release without the expense of inductive protein(s) is highly attractive in the area of tissue-engineered bone and offers significant future potential in the field of regenerative biomaterials.

  13. Neuroimaging evidence of brain abnormalities in mastocytosis.

    PubMed

    Boddaert, N; Salvador, A; Chandesris, M O; Lemaître, H; Grévent, D; Gauthier, C; Naggara, O; Georgin-Lavialle, S; Moura, D S; Munsch, F; Jaafari, N; Zilbovicius, M; Lortholary, O; Gaillard, R; Hermine, O

    2017-08-08

    Mastocytosis is a rare disease in which chronic symptoms are related to mast cell accumulation and activation. Patients can display depression-anxiety-like symptoms and cognitive impairment. The pathophysiology of these symptoms may be associated with tissular mast cell infiltration, mast cell mediator release or both. The objective of this study is to perform morphological or functional brain analyses in mastocytosis to identify brain changes associated with this mast cell disorder. We performed a prospective and monocentric comparative study to evaluate the link between subjective psycho-cognitive complaints, psychiatric evaluation and objective medical data using magnetic resonance imaging with morphological and perfusion sequences (arterial spin-labeled perfusion) in 39 patients with mastocytosis compared with 33 healthy controls. In the test cohort of 39 mastocytosis patients with psycho-cognitive complaints, we found that 49% of them had morphological brain abnormalities, mainly abnormal punctuated white matter abnormalities (WMA). WMA were equally frequent in cutaneous mastocytosis patients and indolent forms of systemic mastocytosis patients (42% and 41% of patients with WMA, respectively). Patients with WMA showed increased perfusion in the putamen compared with patients without WMA and with healthy controls. Putamen perfusion was also negatively correlated with depression subscores. This study demonstrates, for we believe the first time, a high prevalence of morphological and functional abnormalities in the brains of mastocytosis patients with neuropsychiatric complaints. Further studies are required to determine the mechanism underpinning this association and to ascertain its specificity.

  14. Radiation induced abnormalities in early in vitro mouse embryos

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

    Kirkpatrick, J.F.

    1973-08-01

    Female mice were superovulated and mated, and the two-cell embryos were collected and cultured in vitro. The embryos were exposed to x-irradiation (0 to 491 rads) during the two-cell stage before the appearance of the next cleavage plate, placed in new unirradiated culture medium and observed during subsequent development. Morphological abnormalities, which occurred as a result of irradiation, included fragmentation, disintegration, granlation, incomplete cleavage, cleavage cessation, nuclear degeneration and pycnosis and cytoplasmic vacuolization. There was no damage to the zona pellucida. The types of abnormalities indicate an agreement with the results of previous in vivo studies. A distinct correlation existedmore » between morphological abnormalities and embryo death. The greatest number of abnormalities resulted within five hours following irradiation, but increased through 20 hours post-exposure. At doses above 300 rads, the magnitude of damage was greater in the in vitro embryos than that shown in previous in vivo studies. (auth)« less

  15. Facile preparation of efficient electrocatalysts for oxygen reduction reaction: One-dimensional meso/macroporous cobalt and nitrogen Co-doped carbon nanofibers

    NASA Astrophysics Data System (ADS)

    Yoon, Ki Ro; Choi, Jinho; Cho, Su-Ho; Jung, Ji-Won; Kim, Chanhoon; Cheong, Jun Young; Kim, Il-Doo

    2018-03-01

    Efficient electrocatalyst for oxygen reduction reaction (ORR) is an essential component for stable operation of various sustainable energy conversion and storage systems such as fuel cells and metal-air batteries. Herein, we report a facile preparation of meso/macroporous Co and N co-doped carbon nanofibers (Co-Nx@CNFs) as a high performance and cost-effective electrocatalyst toward ORR. Co-Nx@CNFs are simply obtained from electrospinning of Co precursor and bicomponent polymers (PVP/PAN) followed by temperature controlled carbonization and further activation step. The prepared Co-Nx@CNF catalyst carbonized at 700 °C (Co-Nx@CNF700) shows outstanding ORR performance, i.e., a low onset potential (0.941 V) and half wave potential (0.814 V) with almost four-electron transfer pathways (n= 3.9). In addition, Co-Nx@CNF700 exhibits a superior methanol tolerance and higher stability (>70 h) in Zn-air battery in comparison with Pt/C catalyst (∼30 h). The outstanding performance of Co-Nx@CNF700 catalysts is attributed to i) enlarged surface area with bimodal porosity achieved by leaching of inactive species, ii) increase of exposed ORR active Co-Nx moieties and graphitic edge sites, and iii) enhanced electrical conductivity and corrosion resistance due to the existence of numerous graphitic flakes in carbon matrix.

  16. Abnormal Current–Voltage Hysteresis Induced by Reverse Bias in Organic–Inorganic Hybrid Perovskite Photovoltaics

    DOE PAGES

    Rajagopal, Adharsh; Williams, Spencer T.; Chueh, Chu-Chen; ...

    2016-02-29

    In this study, reverse bias (RB)-induced abnormal hysteresis is investigated in perovskite solar cells (PVSCs) with nickel oxide (NiOx)/methylammonium lead iodide (CH 3NH 3PbI 3) interfaces. Through comprehensive current-voltage (I-V) characterization and bias-dependent external quantum efficiency (EQE) measurements, we demonstrate that this phenomenon is caused by the interfacial ion accumulation intrinsic to CH 3NH 3PbI 3. Subsequently, via systematic analysis we discover that the abnormal I-V behavior is remarkably similar to tunnel diode I-V characteristics and is due to the formation of a transient tunnel junction at NiO x/CH 3NH 3PbI 3 interfaces under RB. The detailed analysis navigating themore » complexities of I-V behavior in CH 3NH 3PbI 3-based solar cells provided here ultimately illuminates possibilities in modulating ion motion and hysteresis via interfacial engineering in PVSCs. Moreover, this work shows that RB can alter how CH 3NH 3PbI 3 contributes to the functional nature of devices and provides the first steps toward approaching functional perovskite interfaces in new ways for metrology and analysis of complex transient processes.« less

  17. Gross Motor Development, Movement Abnormalities, and Early Identification of Autism

    PubMed Central

    Young, Gregory S.; Goldring, Stacy; Greiss-Hess, Laura; Herrera, Adriana M.; Steele, Joel; Macari, Suzanne; Hepburn, Susan; Rogers, Sally J.

    2015-01-01

    Gross motor development (supine, prone, rolling, sitting, crawling, walking) and movement abnormalities were examined in the home videos of infants later diagnosed with autism (regression and no regression subgroups), developmental delays (DD), or typical development. Group differences in maturity were found for walking, prone, and supine, with the DD and Autism-No Regression groups both showing later developing motor maturity than typical children. The only statistically significant differences in movement abnormalities were in the DD group; the two autism groups did not differ from the typical group in rates of movement abnormalities or lack of protective responses. These findings do not replicate previous investigations suggesting that early motor abnormalities seen on home video can assist in early identification of autism. PMID:17805956

  18. Normal and abnormal human vestibular ocular function

    NASA Technical Reports Server (NTRS)

    Peterka, R. J.; Black, F. O.

    1986-01-01

    The major motivation of this research is to understand the role the vestibular system plays in sensorimotor interactions which result in spatial disorientation and motion sickness. A second goal was to explore the range of abnormality as it is reflected in quantitative measures of vestibular reflex responses. The results of a study of vestibular reflex measurements in normal subjects and preliminary results in abnormal subjects are presented in this report. Statistical methods were used to define the range of normal responses, and determine age related changes in function.

  19. Abnormal dynamics of language in schizophrenia.

    PubMed

    Stephane, Massoud; Kuskowski, Michael; Gundel, Jeanette

    2014-05-30

    Language could be conceptualized as a dynamic system that includes multiple interactive levels (sub-lexical, lexical, sentence, and discourse) and components (phonology, semantics, and syntax). In schizophrenia, abnormalities are observed at all language elements (levels and components) but the dynamic between these elements remains unclear. We hypothesize that the dynamics between language elements in schizophrenia is abnormal and explore how this dynamic is altered. We, first, investigated language elements with comparable procedures in patients and healthy controls. Second, using measures of reaction time, we performed multiple linear regression analyses to evaluate the inter-relationships among language elements and the effect of group on these relationships. Patients significantly differed from controls with respect to sub-lexical/lexical, lexical/sentence, and sentence/discourse regression coefficients. The intercepts of the regression slopes increased in the same order above (from lower to higher levels) in patients but not in controls. Regression coefficients between syntax and both sentence level and discourse level semantics did not differentiate patients from controls. This study indicates that the dynamics between language elements is abnormal in schizophrenia. In patients, top-down flow of linguistic information might be reduced, and the relationship between phonology and semantics but not between syntax and semantics appears to be altered. Published by Elsevier Ireland Ltd.

  20. Higher educational attainment associated with reduced likelihood of abnormal cervical lesions among Zambian women - a cross sectional study.

    PubMed

    Hamoonga, Twaambo Euphemia; Likwa, Rosemary Ndonyo; Musonda, Patrick; Michelo, Charles

    2017-10-13

    The high burden of cervical cancer in Zambia prompted the Ministry of Health and partners to develop the cervical cancer prevention program in Zambia (CCPPZ) in 2006. Despite this intervention more women continue to die from the disease and there is little understanding of factors that may be linked with abnormal cervical lesions in the general population. We therefore examined if educational attainment is associated with abnormal cervical lesions among Zambian women aged 15 to 49 years. This study used data from the cervical cancer prevention program in Zambia, where a total of 14,294 women aged 15 to 49 years were screened for cervical cancer at nine health facilities between October 2013 and September 2014. The data represents women from six provinces of Zambia, namely Southern, Central, Copperbelt, Luapula, North-western and Eastern provinces. Step-wise logistic regression analysis using the Statistical Package for the Social Sciences (SPSS) version 21 was used to estimate adjusted odds ratios (AOR) and 95% confidence intervals (CIs) for educational attainment with presence of abnormal cervical lesions as outcome. Multiple imputation was further used to obtain the imputed stabilized estimates for educational attainment. The prevalence of abnormal cervical lesions, using the Visual Inspection with Acetic-acid (VIA) test was 10.7% (n = 1523). Educational attainment was inversely associated with abnormal cervical lesions (AOR = 0.75; 95% CI:0.70-0.81, AOR = 0.74; 95% CI:0.68-0.81 and AOR = 0.46; 95% CI:0.41-0.51) among women with primary, secondary and tertiary education, respectively, compared to those with no formal education. We find reduced likelihood of abnormal cervical lesions in educated women, suggesting a differential imbalance with women who have no formal education. These findings may be a reflection of inequalities associated with access to cervical cancer screening, making the service inadequately accessible for lower educated groups. This