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Sample records for hybrid synthetic tubular

  1. Approaches to hybrid synthetic devices

    Science.gov (United States)

    Verma, Vivek

    All living creatures are made up of cells that have the ability to replicate themselves in a repetitive process called cell division. As these cells mature and divide into two there is an extensive movement of cellular components. In order to perform this essential task that sustains life, cells have evolved machines composed of proteins. Biological motors, such as kinesin, transport intracellular cargo and position organelles in eukaryotic cells via unidirectional movement on cytoskeletal tracts called microtubules. Biomolecular motor proteins have the potential to be used as 'nano-engines' for switchable devices, directed self assembly, controlled bioseparations and powering nano- and microelectromechanical systems. However, engineering such systems requires fabrication processes that are compatible with biological materials such as kinesin motor proteins and microtubules. The first objective of the research was to establish biocompatibility between protein systems and nanofabrication. The second objective was to use current micro- and nanofabrication techniques for patterning proteins at specific locations and to study role of casein in supporting the operation of surface bound kinesin. The third objective was to link kinesin and microtubule system to cellulose nanowhiskers. The effects of micro- and nanofabrication processing chemicals and resists on the functionality of casein, kinesin, and microtubule proteins are systematically examined to address the important missing link of the biocompatibility of micro- and nanofabrication processes needed to realize hybrid system fabrication. It was found that both casein, which is used to prevent motor denaturation on surfaces, and kinesin motors are surprisingly tolerant of most of the processing chemicals examined. Microtubules, however, are much more sensitive. Exposure to the processing chemicals leads to depolymerization, which is partially attributed to the pH of the solutions examined. When the chemicals were

  2. A tubular hybrid Halbach/axially-magnetized permanent-magnet linear machine

    Directory of Open Access Journals (Sweden)

    Yi Sui

    2017-05-01

    Full Text Available A single-phase tubular permanent-magnet linear machine (PMLM with hybrid Halbach/axially-magnetized PM arrays is proposed for free-piston Stirling power generation system. Machine topology and operating principle are elaborately illustrated. With the sinusoidal speed characteristic of the free-piston Stirling engine considered, the proposed machine is designed and calculated by finite-element analysis (FEA. The main structural parameters, such as outer radius of the mover, radial length of both the axially-magnetized PMs and ferromagnetic poles, axial length of both the middle and end radially-magnetized PMs, etc., are optimized to improve both the force capability and power density. Compared with the conventional PMLMs, the proposed machine features high mass and volume power density, and has the advantages of simple control and low converter cost. The proposed machine topology is applicable to tubular PMLMs with any phases.

  3. A tubular hybrid Halbach/axially-magnetized permanent-magnet linear machine

    Science.gov (United States)

    Sui, Yi; Liu, Yong; Cheng, Luming; Liu, Jiaqi; Zheng, Ping

    2017-05-01

    A single-phase tubular permanent-magnet linear machine (PMLM) with hybrid Halbach/axially-magnetized PM arrays is proposed for free-piston Stirling power generation system. Machine topology and operating principle are elaborately illustrated. With the sinusoidal speed characteristic of the free-piston Stirling engine considered, the proposed machine is designed and calculated by finite-element analysis (FEA). The main structural parameters, such as outer radius of the mover, radial length of both the axially-magnetized PMs and ferromagnetic poles, axial length of both the middle and end radially-magnetized PMs, etc., are optimized to improve both the force capability and power density. Compared with the conventional PMLMs, the proposed machine features high mass and volume power density, and has the advantages of simple control and low converter cost. The proposed machine topology is applicable to tubular PMLMs with any phases.

  4. DNA meets synthetic polymers—highly versatile hybrid materials

    NARCIS (Netherlands)

    Alemdaroglu, Fikri E.; Herrmann, Andreas

    2007-01-01

    The combination of synthetic polymers and DNA has provided biologists, chemists and materials scientists with a fascinating new hybrid material. The challenges in preparing these molecular chimeras were overcome by different synthetic strategies that rely on coupling the nucleic acid moiety and the

  5. Undulating tubular liposomes through incorporation of a synthetic skin ceramide into phospholipid bilayers.

    Science.gov (United States)

    Xu, Peng; Tan, Grace; Zhou, Jia; He, Jibao; Lawson, Louise B; McPherson, Gary L; John, Vijay T

    2009-09-15

    Nonspherical liposomes were prepared by doping L-alpha-phosphatidylcholine (PC) with ceramide VI (a skin lipid). Cryo-transmission electron microscopy shows the liposome shape changing from spherical to an undulating tubular morphology, when the amount of ceramide VI is increased. The formation of tubular liposomes is energetically favorable and is attributed to the association of ceramide VI with PC creating regions of lower curvature. Since ceramides are the major component of skin lipids in the stratum corneum, tubular liposomes containing ceramide may potentially serve as self-enhanced nanocarriers for transdermal delivery.

  6. Undulating tubular liposomes through incorporation of a synthetic skin ceramide into phospholipid bilayers

    OpenAIRE

    Xu, Peng; Tan, Grace; Zhou, Jia; He, Jibao; Lawson, Louise B.; McPherson, Gary L.; John, Vijay T.

    2009-01-01

    Non-spherical liposomes were prepared by doping L-α-phosphatidylcholine (PC) with ceramide VI (a skin lipid). Cryo-transmission electron microscopy shows the liposome shape changing from spherical to an undulating tubular morphology, when the amount ofceramide VI is increased. The formation of tubular liposomes is energetically favorableand is attributed to the association of ceramide VI with PC creating regions of lower curvature. Since ceramides are the major component of skin lipids inthe ...

  7. Undulating tubular liposomes through incorporation of a synthetic skin ceramide into phospholipid bilayers

    OpenAIRE

    Xu, Peng; Tan, Grace; Zhou, Jia; He, Jibao; Lawson, Louise B.; McPherson, Gary L.; John, Vijay T.

    2009-01-01

    Non-spherical liposomes were prepared by doping L-α-phosphatidylcholine (PC) with ceramide VI (a skin lipid). Cryo-transmission electron microscopy shows the liposome shape changing from spherical to an undulating tubular morphology, when the amount ofceramide VI is increased. The formation of tubular liposomes is energetically favorableand is attributed to the association of ceramide VI with PC creating regions of lower curvature. Since ceramides are the major component of skin lipids inthe ...

  8. Hybrid protein-synthetic polymer nanoparticles for drug delivery.

    Science.gov (United States)

    Koseva, Neli S; Rydz, Joanna; Stoyanova, Ekaterina V; Mitova, Violeta A

    2015-01-01

    Among the most common nanoparticulate systems, the polymeric nanocarriers have a number of key benefits, which give a great choice of delivery platforms. Nevertheless, polymeric nanoparticles possess some limitations that include use of toxic solvents in the production process, polymer degradation, drug leakage outside the diseased tissue, and polymer cytotoxicity. The combination of polymers of biological and synthetic origin is an appealing modern strategy for the production of novel nanocarriers with unprecedented properties. Proteins' interface can play an important role in determining bioactivity and toxicity and gives perspective for future development of the polymer-based nanoparticles. The design of hybrid constructs composed of synthetic polymer and biological molecules such as proteins can be considered as a straightforward tool to integrate a broad spectrum of properties and biofunctions into a single device. This review discusses hybrid protein-synthetic polymer nanoparticles with different structures and levels in complexity and functionality, in view of their applications as drug delivery systems.

  9. Hybrid Block Copolymers Constituted by Peptides and Synthetic Polymers: An Overview of Synthetic Approaches, Supramolecular Behavior and Potential Applications

    Directory of Open Access Journals (Sweden)

    Jordi Puiggalí

    2013-02-01

    Full Text Available Hybrid block copolymers based on peptides and synthetic polymers, displaying different types of topologies, offer new possibilities to integrate the properties and functions of biomacromolecules and synthetic polymers in a single hybrid material. This review provides a current status report of the field concerning peptide-synthetic polymer hybrids. The first section is focused on the different synthetic approaches that have been used within the last three years for the preparation of peptide-polymer hybrids having different topologies. In the last two sections, the attractive properties, displayed in solution or in the solid state, together with the potential applications of this type of macromolecules or supramolecular systems are highlighted.

  10. Synthetic Dye - Inorganic Salt Hybrid Colorants for Application in Thermoplastics

    Directory of Open Access Journals (Sweden)

    Hong-Wen Gao

    2011-06-01

    Full Text Available Common synthetic dyes, e.g., Weak Acid Pink Red B (APRB, C.I. 18073, Mordant Blue 9 (MB, C.I.14855 and Acid Brilliant Blue 6B (ABB6B, C.I. 42660, can be removed from water by in situ hybridization with CaCO3, BaSO4 and Ca3(PO42 and the resulting hybrids thus prepared used as plastic colorants. All the hybrids can be processed into polypropylene (PP at 200 °C with good color intensity, color brightness and homogeneous dispersion. The BaSO4-MB hybrid exhibits better migration resistance to acid and alkali, and stronger covering power than the BaSO4-MB mixture. The thermal stability and UV resistance of the Ca3(PO42-ABB6B hybrid are better than those of the Ca3(PO42-ABB6B mixture. The crystallinity of PP is enhanced by incorporation of these hybrids and the use of these hybrids as colorants in PP instead of the dyes alone is determined to be feasible.

  11. Studies on synthetic LuxR solo hybrids

    Directory of Open Access Journals (Sweden)

    Daniel ePassos da Silva

    2015-06-01

    Full Text Available A sub-group of LuxR family of proteins that plays important roles in quorum sensing, a process of cell-cell communication, is widespread in proteobacteria. These proteins have a typical modular structure consisting of N-ter autoinducer binding and C-ter helix-turn-helix (HTH DNA binding domains. The autoinducer binding domain recognizes signaling molecules which are most often N-acyl homoserine lactones (AHLs but could also be other novel and yet unidentified molecules. In this study we carried out a series of specific domain swapping and promoter activation experiments as a first step to engineer synthetic signaling modules, taking advantage of the modularity and the versatile/diverse signal specificities of LuxR proteins. In our experiments the N-ter domains from different LuxR homologs were either interchanged or placed in tandem followed by a C-ter domain. The rational design of the hybrid proteins was supported by a structure-based homology modeling studies of three members of the LuxR family (i.e. LasR, RhlR and OryR being chosen for their unique ligand binding specificities and of selected chimeras. Our results reveal that these LuxR homologs were able to activate promoter elements that were not their usual targets; we also show that hybrid LuxR proteins retained the ability to recognize the signal specific for their N- ter autoinducer binding domain. However, the activity of hybrid LuxR proteins containing two AHL binding domains in tandem appears to depend on the organization and nature of the introduced domains. This study represents advances in the understanding of the modularity of LuxR proteins and provides additional possibilities to use hybrid proteins in both basic and applied synthetic biology based research.

  12. Studies on synthetic LuxR solo hybrids.

    Science.gov (United States)

    da Silva, Daniel Passos; Patel, Hitendra K; González, Juan F; Devescovi, Giulia; Meng, Xianfa; Covaceuszach, Sonia; Lamba, Doriano; Subramoni, Sujatha; Venturi, Vittorio

    2015-01-01

    A sub-group of LuxR family of proteins that plays important roles in quorum sensing, a process of cell-cell communication, is widespread in proteobacteria. These proteins have a typical modular structure consisting of N-ter autoinducer binding and C-ter helix-turn-helix (HTH) DNA binding domains. The autoinducer binding domain recognizes signaling molecules which are most often N-acyl homoserine lactones (AHLs) but could also be other novel and yet unidentified molecules. In this study we carried out a series of specific domain swapping and promoter activation experiments as a first step to engineer synthetic signaling modules, taking advantage of the modularity and the versatile/diverse signal specificities of LuxR proteins. In our experiments the N-ter domains from different LuxR homologs were either interchanged or placed in tandem followed by a C-ter domain. The rational design of the hybrid proteins was supported by a structure-based homology modeling studies of three members of the LuxR family (i.e., LasR, RhlR, and OryR being chosen for their unique ligand binding specificities) and of selected chimeras. Our results reveal that these LuxR homologs were able to activate promoter elements that were not their usual targets; we also show that hybrid LuxR proteins retained the ability to recognize the signal specific for their N- ter autoinducer binding domain. However, the activity of hybrid LuxR proteins containing two AHL binding domains in tandem appears to depend on the organization and nature of the introduced domains. This study represents advances in the understanding of the modularity of LuxR proteins and provides additional possibilities to use hybrid proteins in both basic and applied synthetic biology based research.

  13. RNA probes, transcribed from synthetic DNA, for in situ hybridization

    Energy Technology Data Exchange (ETDEWEB)

    Brysch, W.; Hagendorff, G.; Schlingensiepen, K.H.

    1988-03-25

    Single stranded cRNA probes are ideal for in-situ-hybridization. Synthetic oligodesoxy-ribonucleotides on the other hand allow one to chose nucleotide sequences independently of restriction sites and availability of cloned templates. To combine the advantages of these two methods, the authors used an oligonucleotide, containing a T7-RNA-polymerase promotor sequence and a starting sequence of 6 bases as a template for an in-vitro-transcription reaction with T7-RNA-polymerase. A second oligonucleotide, complementary to basepairs 1-101 was also synthesized and the two strands heated to 95/sup 0/ for 3 min, then kept at 65/sup 0/C for one hour in 80 mM Tris, 12mM MgCl, 4 mM Spermidine, 0,04% Triton and finally cooled on ice. The resulting double stranded DNA was used as a template to transcribe /sup 35/S-labelled cRNA, using DNA, T7-Polymerase, /sup 35/S-UTP, ATP, GTP and CTP and RNasin (Promega). No difference could be observed comparing the resulting hybridization pattern with that obtained by using a plasmid derived cRNA probe of rat brain sodium channel II. Moreover the hybridization signal was clearly distinct from the background labelling resulting from hybridization with a sense control probe of the same specific activity.

  14. Polarimetric Synthetic Aperture Radar Image Classification by a Hybrid Method

    Institute of Scientific and Technical Information of China (English)

    Kamran Ullah Khan; YANG Jian

    2007-01-01

    Different methods proposed so far for accurate classification of land cover types in polarimetric synthetic aperture radar (SAR) image are data specific and no general method is available. A novel hybrid framework for this classification was developed in this work. A set of effective features derived from the coherence matrix of polarimetric SARdata was proposed.Constituents of the feature set are wavelet,texture,and nonlinear features.The proposed feature set has a strong discrimination power. A neural network was used as the classification engine in a unique way. By exploiting the speed of the conjugate gradient method and the convergence rate of the Levenberg-Marquardt method (near the optimal point), an overall speed up of the classification procedure was achieved. Principal component analysis(PCA)was used to shrink the dimension of the feature vector without sacrificing much of the classification accuracy. The proposed approach is compared with the maximum likelihood estimator (MLE)based on the complex Wishart distribution and the results show the superiority of the proposed method,with the average classification accuracy by the proposed method(95.4%)higher than that of the MLE(93.77%). Use of PCA to reduce the dimensionality of the feature vector helps reduce the memory requirements and computational cost, thereby enhancing the speed of the process.

  15. Novel hybrid FRP tubular columns for sustainable mining infrastructure:Recent research at University of Wollongong

    Institute of Scientific and Technical Information of China (English)

    Yu Tao; Remennikov Alex M.

    2014-01-01

    This paper introduces, for applications in the mining industry, an innovative hybrid column form which consists of an inner steel tube, an outer fibre-reinforced polymer (FRP) tube and an annular concrete infill between them. The two tubes may be concentrically placed to produce a section form more suitable for columns, or eccentrically placed to produce a section form more suitable for beams. The FRP is combined with steel and concrete in these hybrid structural members in such a way that the advantages of FRP are appropriately exploited while its disadvantages are minimized. As a result, these hybrid members pos-sess excellent corrosion resistance as well as excellent ductility and seismic resistance. This paper sum-marizes existing research on this new form of structural members, and discusses their potential applications in mining infrastructure before presenting a summary of the recent and current studies at University of Wollongong (UOW) on their structural behaviour and design.

  16. Controlling promoter strength and regulation in Saccharomyces cerevisiae using synthetic hybrid promoters.

    Science.gov (United States)

    Blazeck, John; Garg, Rishi; Reed, Ben; Alper, Hal S

    2012-11-01

    A dynamic range of well-controlled constitutive and tunable promoters are essential for metabolic engineering and synthetic biology applications in all host organisms. Here, we apply a synthetic hybrid promoter approach for the creation of strong promoter libraries in the model yeast, Saccharomyces cerevisiae. Synthetic hybrid promoters are composed of two modular components-the enhancer element, consisting of tandem repeats or combinations of upstream activation sequences (UAS), and the core promoter element. We demonstrate the utility of this approach with three main case studies. First, we establish a dynamic range of constitutive promoters and in doing so expand transcriptional capacity of the strongest constitutive yeast promoter, P(GPD) , by 2.5-fold in terms of mRNA levels. Second, we demonstrate the capacity to impart synthetic regulation through a hybrid promoter approach by adding galactose activation and removing glucose repression. Third, we establish a collection of galactose-inducible hybrid promoters that span a nearly 50-fold dynamic range of galactose-induced expression levels and increase the transcriptional capacity of the Gal1 promoter by 15%. These results demonstrate that promoters in S. cerevisiae, and potentially all yeast, are enhancer limited and a synthetic hybrid promoter approach can expand, enhance, and control promoter activity.

  17. Plant genetics affects arthropod community richness and composition: evidence from a synthetic eucalypt hybrid population.

    Science.gov (United States)

    Dungey, H S; Potts, B M; Whitham, T G; Li, H F

    2000-12-01

    To examine how genetic variation in a plant population affects arthropod community richness and composition, we quantified the arthropod communities on a synthetic population of Eucalyptus amygdalina, E. risdonii, and their F1 and advanced-generation hybrids. Five major patterns emerged. First, the pure species and hybrid populations supported significantly different communities. Second, species richness was significantly greatest on hybrids (F1 > F2 > E. amygdalina > E. risdonii). These results are similar to those from a wild population of the same species and represent the first case in which both synthetic and wild population studies confirm a genetic component to community structure. Hybrids also acted as centers of biodiversity by accumulating both the common and specialist taxa of both parental species (100% in the wild and 80% in the synthetic population). Third, species richness was significantly greater on F1s than the single F2 family, suggesting that the increased insect abundance on hybrids may not be caused by the breakup of coadapted gene complexes. Fourth, specialist arthropod taxa were most likely to show a dominance response to F1 hybrids, whereas generalist taxa exhibited a susceptible response. Fifth, in an analysis of 31 leaf terpenoids that are thought to play a role in plant defense, hybrids were generally intermediate to the parental chemotypes. Within the single F2 family, we found significant associations between the communities of individual trees and five individual oil components, including oil yield, demonstrating that there is a genetic effect on plant defensive chemistry that, in turn, may affect community structure. These studies argue that hybridization has important community-level consequences and that the genetic variation present in hybrid zones can be used to explore the genetic-based mechanisms that structure communities.

  18. Equipment for the Characterization of Synthetic Bio-hybrid Polymers and Micellar Nanoparticles for Stimuli Responsive Materials

    Science.gov (United States)

    2015-02-08

    reactions. These materials couple together synthetic polymers with biopolymers including DNA, peptides and proteins. The project therefore requires a... Synthetic Bio-hybrid Polymers and Micellar Nanoparticles for Stimuli Responsive Materials. The views, opinions and/or findings contained in this...this instrument in terms of fully characterizing biomolecule interactions occurring at the interface of semi- synthetic biopolymer -based nano materials

  19. Natural Cinnamic Acids, Synthetic Derivatives and Hybrids with Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Juan David Guzman

    2014-11-01

    Full Text Available Antimicrobial natural preparations involving cinnamon, storax and propolis have been long used topically for treating infections. Cinnamic acids and related molecules are partly responsible for the therapeutic effects observed in these preparations. Most of the cinnamic acids, their esters, amides, aldehydes and alcohols, show significant growth inhibition against one or several bacterial and fungal species. Of particular interest is the potent antitubercular activity observed for some of these cinnamic derivatives, which may be amenable as future drugs for treating tuberculosis. This review intends to summarize the literature data on the antimicrobial activity of the natural cinnamic acids and related derivatives. In addition, selected hybrids between cinnamic acids and biologically active scaffolds with antimicrobial activity were also included. A comprehensive literature search was performed collating the minimum inhibitory concentration (MIC of each cinnamic acid or derivative against the reported microorganisms. The MIC data allows the relative comparison between series of molecules and the derivation of structure-activity relationships.

  20. Towards Self-Assembled Hybrid Artificial Cells: Novel Bottom-Up Approaches to Functional Synthetic Membranes

    Science.gov (United States)

    Brea, Roberto J.; Hardy, Michael D.; Devaraj, Neal K.

    2015-01-01

    There has been increasing interest in utilizing bottom-up approaches to develop synthetic cells. A popular methodology is the integration of functionalized synthetic membranes with biological systems, producing “hybrid” artificial cells. This Concept article covers recent advances and the current state-of-the-art of such hybrid systems. Specifically, we describe minimal supramolecular constructs that faithfully mimic the structure and/or function of living cells, often by controlling the assembly of highly ordered membrane architectures with defined functionality. These studies give us a deeper understanding of the nature of living systems, bring new insights into the origin of cellular life, and provide novel synthetic chassis for advancing synthetic biology. PMID:26149747

  1. Synthetic dye--inorganic salt hybrid colorants for application in thermoplastics.

    Science.gov (United States)

    Wei, Yan-Ping; Li, Tian; Gao, Hong-Wen

    2011-06-17

    Common synthetic dyes, e.g., Weak Acid Pink Red B (APRB, C.I. 18073), Mordant Blue 9 (MB, C.I.14855) and Acid Brilliant Blue 6B (ABB6B, C.I. 42660), can be removed from water by in situ hybridization with CaCO(3), BaSO(4) and Ca(3)(PO(4))(2) and the resulting hybrids thus prepared used as plastic colorants. All the hybrids can be processed into polypropylene (PP) at 200 °C with good color intensity, color brightness and homogeneous dispersion. The BaSO(4)-MB hybrid exhibits better migration resistance to acid and alkali, and stronger covering power than the BaSO(4)-MB mixture. The thermal stability and UV resistance of the Ca(3)(PO(4))(2)-ABB6B hybrid are better than those of the Ca(3)(PO(4))(2)-ABB6B mixture. The crystallinity of PP is enhanced by incorporation of these hybrids and the use of these hybrids as colorants in PP instead of the dyes alone is determined to be feasible.

  2. Characterization of hybridization between synthetic oligodeoxynucleotides and RNA in living cells.

    Science.gov (United States)

    Politz, J C; Taneja, K L; Singer, R H

    1995-01-01

    Cells internalized synthetic oligonucleotides (oligos) in culture. The hybridization of these molecules to target RNA in the living cell was subsequently detected and characterized after fixation of the cells, with or without previous detergent extraction. Hybridized oligo was distinguished from free oligo in the cell using an in situ reverse transcription technique. This assay exploited the ability of the hybridized oligo to prime synthesis of a specific cDNA strand; unhybridized oligo present in the cell could not act as a primer for reverse transcription. Phosphorothioate and fluorochrome-labeled phosphodiester oligo dT were found to enter cells rapidly and hybridize to poly (A) RNA within 30 min. Hybrids containing phosphorothioate oligo dT were detectable in cells after up to 4 h of efflux time. Phosphodiester bonded oligo dT containing covalently-linked fluorochromes appeared more stable in the cell than unmodified phosphodiester oligo dT; hybrids containing these oligos could be detected in cells as long as 18h after efflux began. The in situ transcription assay was also sensitive enough to detect hybridization of anti-actin oligos to actin mRNA in the cell. It is probable, therefore, that this assay can be used to help assess the efficacy of antisense oligos by their hybridization to a target mRNA in cells or tissues; hybridized oligos are more likely to induce a specific antisense effect. Additionally, this assay will help to identify probes that would be useful as stable hybridization tags to follow RNA movement in living cells. Images PMID:8559650

  3. Hybrid Nanomaterials by Surface Grafting of Synthetic Polypeptides Using N-Carboxyanhydride (NCA) Polymerization.

    Science.gov (United States)

    Borase, Tushar; Heise, Andreas

    2016-07-01

    The interaction of materials with their environment is largely dictated by interfacial phenomena. Polymers are very versatile materials to modulate material interfaces to provide functionality, stability and compatibility. A class of polymers that can close the gap between fully synthetic and natural macromolecules are polypeptides derived from N-carboxyanhydride (NCA) polymerization. Recent advances in using this technique to create biomimetic interfaces and hybrid materials are highlighted, with special emphasis on nanomaterials.

  4. HMGA1a protein unfolds or refolds synthetic DNA-chromophore hybrid polymers: a chaperone-like behavior.

    Science.gov (United States)

    Wan, Wei; Wang, Wei; Li, Alexander D Q

    2008-01-25

    High group mobility protein, HMGA1a, was found to play a chaperone-like role in the folding or unfolding of hybrid polymers that contained well-defined synthetic chromophores and DNA sequences. The synthetic and biological hybrid polymers folded into hydrophobic chromophoric nanostructures in water, but existed as partially unfolded configurations in pH or salt buffers. The presence of HMGA1a induced unfolding of the hybrid DNA-chromophore polymer in pure water, whereas the protein promoted refolding of the same polymer in various pH or salt buffers. The origin of the chaperone-like properties probably comes from the ability of HMGA1a to reversibly bind both synthetic chromophores and single stranded DNA. The unfolding mechanisms and the binding stoichiometry of protein-hybrid polymers depended on the sequence of the synthetic polymers.

  5. Exploration of aziridine- and β-lactam-based hybrids as both bioactive substances and synthetic intermediates in medicinal chemistry.

    Science.gov (United States)

    Vandekerckhove, Stéphanie; D'hooghe, Matthias

    2013-07-01

    The concept of pharmacophore hybridization is attracting an increasing interest from medicinal chemists. Whereas the main motivation for the application of this methodology relates to the pharmacological advantages associated with hybrid molecules, molecular hybridization can also deliver a synthetic advantage through selective chemical modification of the more reactive entity within hybrid systems. Moreover, if both features are combined, new hybrid structures result displaying both a biological and a synthetic benefit, and elaboration of this methodology might culminate in structural diversity and chemical novelty. In this perspective, a new approach based on hybrid structures combining a biologically interesting yet rather chemically reactive nucleus with a privileged heterocyclic scaffold is discussed by means of β-lactam-purine chimeras useful in antiviral research and aziridine-(iso)quinoline hybrids for antimalarial purposes.

  6. Green synthetic, multifunctional hybrid micelles with shell embedded magnetic nanoparticles for theranostic applications.

    Science.gov (United States)

    Li, Yongyong; Ma, Junping; Zhu, Haiyan; Gao, Xiaolong; Dong, Haiqing; Shi, Donglu

    2013-08-14

    The objective of this study is to design and develop a green-synthetic, multifunctional hybrid micelles with shell embedded magnetic nanoparticles for theranostic applications. The hybrid micelles were engineered based on complex micelles self-assembled from amphiphilic block copolymers Pluronic F127 and peptide-amphiphile (PA) pal-AAAAHHHD. The reason to choose PA is due to its amphiphilic character and the coordination capability for Fe(3+) and Fe(2+). The PA incorporation allows the in situ growth of the magnetic iron oxide nanoparticles onto the complex micelles, to yield the nanostructures with shell embedded magnetic nanoparticles at an ambient condition without any organic solvents. The anticancer drug doxorubicin (DOX) can be efficiently loaded into the hybrid micelles. Interestingly, the magnetic nanoparticles anchored on the shell were found to significantly retard the DOX release behavior of the drug loaded hybrid micelles. It was proposed that a cross-linking effect of the shell by magnetic nanoparticles is a key to underlie the above intriguing phenomenon, which could enhance the stability and control the drug diffusion of the hybrid micelles. Importantly, in vitro and in vivo magnetic resonance imaging (MRI) revealed the potential of these hybrid micelles to be served as a T2-weighted MR imaging contrast enhancer for clinical diagnosis.

  7. Development of a hybrid scaffold with synthetic biomaterials and hydrogel using solid freeform fabrication technology

    Energy Technology Data Exchange (ETDEWEB)

    Shim, Jin-Hyung; Park, Min; Park, Jaesung; Cho, Dong-Woo [Department of Mechanical Engineering, POSTECH (Korea, Republic of); Kim, Jong Young, E-mail: dwcho@postech.ac.kr [Department of Mechanical Engineering, Andong National University (Korea, Republic of)

    2011-09-15

    Natural biomaterials such as hyaluronic acid, gelatin and collagen provide excellent environments for tissue regeneration. Furthermore, gel-state natural biomaterials are advantageous for encapsulating cells and growth factors. In cell printing technology, hydrogel which contains cells was printed directly to form three-dimensional (3D) structures for tissue or organ regeneration using various types of printers. However, maintaining the 3D shape of the printed structure, which is made only of the hydrogel, is very difficult due to its weak mechanical properties. In this study, we developed a hybrid scaffold consisting of synthetic biomaterials and natural hydrogel using a multi-head deposition system, which is useful in solid freeform fabrication technology. The hydrogel was intentionally infused into the space between the lines of a synthetic biomaterial-based scaffold. The cellular efficacy of the hybrid scaffold was validated using rat primary hepatocytes and a mouse pre-osteoblast MC3T3-E1 cell line. In addition, the collagen hydrogel, which encapsulates cells, was dispensed and the viability of the cells observed. We demonstrated superior effects of the hybrid scaffold on cell adhesion and proliferation and showed the high viability of dispensed cells.

  8. Photoactive Hybrid Catalysts Based on Natural and Synthetic Polymers: A Comparative Overview.

    Science.gov (United States)

    Colmenares, Juan Carlos; Kuna, Ewelina

    2017-05-12

    In the present review, we would like to draw the reader's attention to the polymer-based hybrid materials used in photocatalytic processes for efficient degradation of organic pollutants in water. These inorganic-organic materials exhibit unique physicochemical properties due to the synergistic effect originating from the combination of individual elements, i.e., photosensitive metal oxides and polymeric supports. The possibility of merging the structural elements of hybrid materials allows for improving photocatalytic performance through (1) an increase in the light-harvesting ability; (2) a reduction in charge carrier recombination; and (3) prolongation of the photoelectron lifetime. Additionally, the great majority of polymer materials exhibit a high level of resistance against ultraviolet irradiation and improved corrosion resistance. Taking into account that the chemical and environmental stability of the hybrid catalyst depends, to a great extent, on the functional support, we highlight benefits and drawbacks of natural and synthetic polymer-based photocatalytic materials and pay special attention to the fact that the accessibility of synthetic polymeric materials derived from petroleum may be impeded due to decreasing amounts of crude oil. Thus, it is necessary to look for cheap and easily available raw materials like natural polymers that come from, for instance, lignocellulosic wastes or crustacean residues to meet the demand of the "plastic" market.

  9. A new method for fluid input into a hybrid synthetic jet actuator

    Directory of Open Access Journals (Sweden)

    Kordík J.

    2014-03-01

    Full Text Available A new principle of flow rectification for hybrid synthetic jet actuators is introduced in this paper. As is well known, the flow rectification can be best accomplished by means of fluidic diodes. Novelty of the present study are fluidic diodes with two mutually opposed nozzles. Interaction between the periodic jet flows from the nozzles causes a difference between the blowing and suction strokes, resulting in a particularly efficient rectification effect. The distance between the nozzle exits as well as the oscillation frequency were the parameters, which were varied during hot-wire measurements. The combination of those parameters achieving the highest volumetric effciency was identified.

  10. Polyhydroxyalkanoate-based natural synthetic hybrid copolymer films: A small-angle neutron scattering study

    Science.gov (United States)

    Foster, L. John R.; Knott, Robert; Sanguanchaipaiwong, Vorapat; Holden, Peter J.

    2006-11-01

    Polyhydroxyalkanoates have attracted attention as biodegradable alternatives to conventional thermoplastics and as biomaterials. Through modification of their biosynthesis using Pseudomonas oleovorans, we have manipulated the material properties of these biopolyesters and produced a natural-synthetic hybrid copolymer of polyhydroxyoctanoate- block-diethylene glycol (PHO- b-DEG). A mixture of PHO and PHO-DEG were solvent cast from analytical grade chloroform and analysed using small-angle neutron scattering. A scattering pattern, easily distinguished above the background, was displayed by the films with a diffraction ring at q∼0.12 Å -1. This narrow ring of intensity is suggestive of a highly ordered system. Analysis of the diffraction pattern supported this concept and showed a d-spacing of approximately 50 Å. In addition, conformation of the hybrid polymer chains can be manipulated to support their self-assembly into ordered microporous films.

  11. Nano Metal-Organic Framework-Derived Inorganic Hybrid Nanomaterials: Synthetic Strategies and Applications.

    Science.gov (United States)

    Mai, Hien Duy; Rafiq, Khezina; Yoo, Hyojong

    2016-11-11

    Nano- (or micro-scale) metal-organic frameworks (NMOFs), also known as coordination polymer particles (CPPs), have received much attention because of their structural diversities and tunable properties. Besides the direct use, NMOFs can be alternatively used as sacrificial templates/precursors for the preparation of a wide range of hybrid inorganic nanomaterials in straightforward and controllable manners. Distinct advantages of using NMOF templates are correlated to their structural and functional tailorability at molecular levels that is rarely acquired in any other conventional template/precursor. In addition, NMOF-derived inorganic nanomaterials with distinct chemical and physical properties are inferred to dramatically expand the scope of their utilization in many fields. In this review, we aim to provide readers with a comprehensive summary of recent progress in terms of synthetic approaches for the production of diverse inorganic hybrid nanostructures from as-synthesized NMOFs and their promising applications.

  12. Polyhydroxyalkanoate-based natural-synthetic hybrid copolymer films: A small-angle neutron scattering study

    Energy Technology Data Exchange (ETDEWEB)

    Foster, L. John R. [Bio/polymer Research Group and Centre for Advanced Macromolecular Design, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney NSW2052 (Australia)]. E-mail: J.Foster@unsw.edu.au; Knott, Robert [Bragg Institute, Institute for Nuclear Geophysiology, Australian Nucelar Science and Technology Organisation, Menai NSW2234 (Australia); Sanguanchaipaiwong, Vorapat [Bio/polymer Research Group and Centre for Advanced Macromolecular Design, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney NSW2052 (Australia); Holden, Peter J. [Institute for Nuclear Geophysiology, Australian Nucelar Science and Technology Organisation, Menai NSW2234 (Australia)

    2006-11-15

    Polyhydroxyalkanoates have attracted attention as biodegradable alternatives to conventional thermoplastics and as biomaterials. Through modification of their biosynthesis using Pseudomonas oleovorans, we have manipulated the material properties of these biopolyesters and produced a natural-synthetic hybrid copolymer of polyhydroxyoctanoate-block-diethylene glycol (PHO-b-DEG). A mixture of PHO and PHO-DEG were solvent cast from analytical grade chloroform and analysed using small-angle neutron scattering. A scattering pattern, easily distinguished above the background, was displayed by the films with a diffraction ring at q{approx}0.12 A{sup -1}. This narrow ring of intensity is suggestive of a highly ordered system. Analysis of the diffraction pattern supported this concept and showed a d-spacing of approximately 50 A. In addition, conformation of the hybrid polymer chains can be manipulated to support their self-assembly into ordered microporous films.

  13. First human use of hybrid synthetic/biologic mesh in ventral hernia repair: a multicenter trial.

    Science.gov (United States)

    Bittner, James G; El-Hayek, Kevin; Strong, Andrew T; LaPinska, Melissa Phillips; Yoo, Jin S; Pauli, Eric M; Kroh, Matthew

    2017-07-19

    Mesh options for reinforcement of ventral/incisional hernia (VIH) repair include synthetic or biologic materials. While each material has known advantages and disadvantages, little is understood about outcomes when these materials are used in combination. This multicenter study reports on the first human use of a novel synthetic/biologic hybrid mesh (Zenapro(®) Hybrid Hernia Repair Device) for VIH repair. This prospective, multicenter post-market clinical trial enrolled consecutive adults who underwent elective VIH repair with hybrid mesh placed in the intraperitoneal or retromuscular/preperitoneal position. Patients were classified as Ventral Hernia Working Group (VHWG) grades 1-3 and had clean or clean-contaminated wounds. Outcomes of ventral and incisional hernia were compared using appropriate parametric tests. In all, 63 patients underwent VIH repair with hybrid mesh. Most were females (54.0%), had a mean age of 54.8 ± 10.9 years and mean body mass index of 34.5 ± 7.8 kg/m(2), and classified as VHWG grade 2 (87.3%). Most defects were midline (92.1%) with a mean area of 106 ± 155 cm(2). Cases were commonly classified as clean (92.1%) and were performed laparoscopically (60.3%). Primary fascial closure was achieved in 82.5% with 28.2% requiring component separation. Mesh location was frequently intraperitoneal (69.8%). Overall, 39% of patients available for follow-up at 12 months suffered surgical site events, which were generally more frequent after incisional hernia repair. Of these, seroma (23.7%) was most common, but few (8.5%) required procedural intervention. Other surgical site events that required procedural intervention included hematoma (1.7%), wound dehiscence (1.7%), and surgical site infection (3.4%). Recurrence rate was 6.8% (95% CI 2.2-16.6%) at 12-months postoperatively. Zenapro(®) Hybrid Hernia Repair Device is safe and effective in VHWG grade 1-2 patients with clean wounds out to 12 months. Short-term outcomes and recurrence

  14. Topical Anti-inflammatory Activity of New Hybrid Molecules of Terpenes and Synthetic Drugs.

    Science.gov (United States)

    Theoduloz, Cristina; Delporte, Carla; Valenzuela-Barra, Gabriela; Silva, Ximena; Cádiz, Solange; Bustamante, Fernanda; Pertino, Mariano Walter; Schmeda-Hirschmann, Guillermo

    2015-06-18

    The aim of the study was to assess changes in the activity of anti-inflammatory terpenes from Chilean medicinal plants after the formation of derivatives incorporating synthetic anti-inflammatory agents. Ten new hybrid molecules were synthesized combining terpenes (ferruginol (1), imbricatolic acid (2) and oleanolic acid (3)) with ibuprofen (4) or naproxen (5). The topical anti-inflammatory activity of the compounds was assessed in mice by the arachidonic acid (AA) and 12-O-tetradecanoyl phorbol 13-acetate (TPA) induced ear edema assays. Basal cytotoxicity was determined towards human lung fibroblasts, gastric epithelial cells and hepatocytes. At 1.4 µmol/mouse, a strong anti-inflammatory effect in the TPA assay was observed for oleanoyl ibuprofenate 12 (79.9%) and oleanoyl ibuprofenate methyl ester 15 (80.0%). In the AA assay, the best activity was observed for 12 at 3.2 µmol/mouse, with 56.8% reduction of inflammation, in the same range as nimesulide (48.9%). All the terpenyl-synthetic anti-inflammatory hybrids showed better effects in the TPA assay, with best activity for 6, 12 and 15. The cytotoxicity of the compounds 8 and 10 with a free COOH, was higher than that of 2. The derivatives from 3 were less toxic than the triterpene. Several of the new compounds presented better anti-inflammatory effect and lower cytotoxicity than the parent terpenes.

  15. Natural-Synthetic Hybrid Polymers Developed via Electrospinning: The Effect of PET in Chitosan/Starch System

    OpenAIRE

    2011-01-01

    Chitosan is an amino polysaccharide found in nature, which is biodegradable, nontoxic and biocompatible. It has versatile features and can be used in a variety of applications including films, packaging, and also in medical surgery. Recently a possibility to diversify chitosan properties has emerged by combining it with synthetic materials to produce novel natural-synthetic hybrid polymers. We have studied structural and thermophysical properties of chitosan + starch + poly(ethylene terephtha...

  16. Synthetic

    Directory of Open Access Journals (Sweden)

    Anna Maria Manferdini

    2010-06-01

    Full Text Available Traditionally materials have been associated with a series of physical properties that can be used as inputs to production and manufacturing. Recently we witnessed an interest in materials considered not only as ‘true matter’, but also as new breeds where geometry, texture, tooling and finish are able to provoke new sensations when they are applied to a substance. These artificial materials can be described as synthetic because they are the outcome of various qualities that are not necessarily true to the original matter, but they are the combination of two or more parts, whether by design or by natural processes. The aim of this paper is to investigate the potential of architectural surfaces to produce effects through the invention of new breeds of artificial matter, using micro-scale details derived from Nature as an inspiration.

  17. Distal renal tubular acidosis

    Science.gov (United States)

    Renal tubular acidosis - distal; Renal tubular acidosis type I; Type I RTA; RTA - distal; Classical RTA ... excreting it into the urine. Distal renal tubular acidosis (Type I RTA) is caused by a defect ...

  18. Proximal renal tubular acidosis

    Science.gov (United States)

    Renal tubular acidosis - proximal; Type II RTA; RTA - proximal; Renal tubular acidosis type II ... by alkaline substances, mainly bicarbonate. Proximal renal tubular acidosis (Type II RTA) occurs when bicarbonate is not ...

  19. Natural-Synthetic Hybrid Polymers Developed via Electrospinning: The Effect of PET in Chitosan/Starch System

    Directory of Open Access Journals (Sweden)

    Carlos Velasco-Santos

    2011-03-01

    Full Text Available Chitosan is an amino polysaccharide found in nature, which is biodegradable, nontoxic and biocompatible. It has versatile features and can be used in a variety of applications including films, packaging, and also in medical surgery. Recently a possibility to diversify chitosan properties has emerged by combining it with synthetic materials to produce novel natural-synthetic hybrid polymers. We have studied structural and thermophysical properties of chitosan + starch + poly(ethylene terephthalate (Ch + S + PET fibers developed via electrospinning. Properties of these hybrids polymers are compared with extant chitosan containing hybrids synthesized by electrospinning. Molecular interactions and orientation in the fibers are analyzed by infrared and Raman spectroscopies respectively, morphology by scanning electron microscopy and thermophysical properties by thermogravimetric analysis and differential scanning calorimetry. Addition of PET to Ch + S systems results in improved thermal stability at elevated temperatures.

  20. Natural-synthetic hybrid polymers developed via electrospinning: the effect of PET in chitosan/starch system.

    Science.gov (United States)

    Espíndola-González, Adolfo; Martínez-Hernández, Ana Laura; Fernández-Escobar, Francisco; Castaño, Victor Manuel; Brostow, Witold; Datashvili, Tea; Velasco-Santos, Carlos

    2011-01-01

    Chitosan is an amino polysaccharide found in nature, which is biodegradable, nontoxic and biocompatible. It has versatile features and can be used in a variety of applications including films, packaging, and also in medical surgery. Recently a possibility to diversify chitosan properties has emerged by combining it with synthetic materials to produce novel natural-synthetic hybrid polymers. We have studied structural and thermophysical properties of chitosan + starch + poly(ethylene terephthalate) (Ch + S + PET) fibers developed via electrospinning. Properties of these hybrids polymers are compared with extant chitosan containing hybrids synthesized by electrospinning. Molecular interactions and orientation in the fibers are analyzed by infrared and Raman spectroscopies respectively, morphology by scanning electron microscopy and thermophysical properties by thermogravimetric analysis and differential scanning calorimetry. Addition of PET to Ch + S systems results in improved thermal stability at elevated temperatures.

  1. Tubular lining material for pipelines having bends

    Energy Technology Data Exchange (ETDEWEB)

    Moringa, A.; Sakaguchi, Y.; Hyodo, M.; Yagi, I.

    1987-03-24

    A tubular lining material for pipelines having bends or curved portions comprises a tubular textile jacket made of warps and wefts woven in a tubular form overlaid with a coating of a flexible synthetic resin. It is applicable onto the inner surface of a pipeline having bends or curved portions in such manner that the tubular lining material with a binder onto the inner surface thereof is inserted into the pipeline and allowed to advance within the pipeline, with or without the aid of a leading rope-like elongated element, while turning the tubular lining material inside out under fluid pressure. In this manner the tubular lining material is applied onto the inner surface of the pipeline with the binder being interposed between the pipeline and the tubular lining material. The lining material is characterized in that a part of all of the warps are comprised of an elastic yarn around which, over the full length thereof, a synthetic fiber yarn or yarns have been left-and/or right-handedly coiled. This tubular lining material is particularly suitable for lining a pipeline having an inner diameter of 25-200 mm and a plurality of bends, such as gas service pipelines or house pipelines, without occurrence of wrinkles in the lining material in a bend.

  2. Synthesis and Characterization of a Chondroitin Sulfate Based Hybrid Bio/Synthetic Biomimetic Aggrecan Macromolecule

    Science.gov (United States)

    Sarkar, Sumona

    Lower back pain resulting from intervertebral disc degeneration is one of the leading musculoskeletal disorders confronting our health system. In order to mechanically stabilize the disc early in the degenerative cascade and prevent the need for spinal fusion surgeries, we have proposed the development of a hybrid-bio/synthetic biomimetic proteoglycan macromolecule for injection into the disc in the early stages of degeneration. The goal of this thesis was to incorporate natural chondroitin sulfate (CS) chains into bottle brush polymer synthesis strategies for the fabrication of CS-macromolecules which mimic the proteoglycan structure and function while resisting enzymatic degradation. Both the "grafting-to" and "grafting-through" techniques of bottle brush synthesis were explored. CS was immobilized via a terminal primary amine onto a model polymeric backbone (polyacrylic acid) for investigation of the "grafting-to" strategy and an epoxy-amine step-growth polymerization technique was utilized for the "grafting-through" synthesis of CS-macromolecules with polyethylene glycol backbone segments. Incorporation of a synthetic polymeric backbone at the terminal amine of CS was confirmed via biochemical assays, 1H-NMR and FTIR spectroscopy, and CS-macromolecule size was demonstrated to be higher than that of natural CS via gel permeation chromatography, transmission electron microscopy and viscosity measurements. Further analysis of CS-macromolecule functionality indicated maintenance of natural CS properties such as high fixed charge density, high osmotic potential and low cytotoxicity with nucleus pulposus cells. These studies are the first attempt at the incorporation of natural CS into biomimetic bottle brush structures. CS-macromolecules synthesized via the methods developed in these studies may be utilized in the treatment and prevention of debilitating back pain as well as act as mimetics for other proteoglycans implicated in cartilage, heart valve, and nervous

  3. Correlation between CdSe QD Synthesis, Post-Synthetic Treatment, and BHJ Hybrid Solar Cell Performance

    Directory of Open Access Journals (Sweden)

    Michael Eck

    2016-06-01

    Full Text Available In this publication we show that the procedure to synthesize nanocrystals and the post-synthetic nanocrystal ligand sphere treatment have a great influence not only on the immediate performance of hybrid bulk heterojunction solar cells, but also on their thermal, long-term, and air stability. We herein demonstrate this for the particular case of spherical CdSe nanocrystals, post-synthetically treated with a hexanoic acid based treatment. We observe an influence from the duration of this post-synthetic treatment on the nanocrystal ligand sphere size, and also on the solar cell performance. By tuning the post-synthetic treatment to a certain degree, optimal device performance can be achieved. Moreover, we show how to effectively adapt the post-synthetic nanocrystal treatment protocol to different nanocrystal synthesis batches, hence increasing the reproducibility of hybrid nanocrystal:polymer bulk-heterojunction solar cells, which usually suffers due to the fluctuations in nanocrystal quality of different synthesis batches and synthesis procedures.

  4. 30-MM Tubular Projectile

    Science.gov (United States)

    1984-10-01

    Suiza tubular projectile 20 9. Inspection of Hispano Suiza sabot 21 10. Inspection of GAU-8 sabot 22 11. Firing data - 30-rn tubular projectile (Hispano... Suiza 23 copper banded) 12. Firing data - 30-m tubular projectile (GAU-8 plastic 24 banded) 13. Firing data - 30-m tubular projectile (GAU-8 copper 25...42 13. In-flight Hispano Suiza tubular projectiles 43 14. In-flight C4U-8 (plastic) tubular projectile 44 15. In-flight GCU-8 (copper) tubular

  5. Probing particle acceleration in lower hybrid turbulence via synthetic diagnostics produced by PIC simulations

    Science.gov (United States)

    Cruz, F.; Fonseca, R. A.; Silva, L. O.; Rigby, A.; Gregori, G.; Bamford, R. A.; Bingham, R.; Koenig, M.

    2016-10-01

    Efficient particle acceleration in astrophysical shocks can only be achieved in the presence of initial high energy particles. A candidate mechanism to provide an initial seed of energetic particles is lower hybrid turbulence (LHT). This type of turbulence is commonly excited in regions where space and astrophysical plasmas interact with large obstacles. Due to the nature of LH waves, energy can be resonantly transferred from ions (travelling perpendicular to the magnetic field) to electrons (travelling parallel to it) and the consequent motion of the latter in turbulent shock electromagnetic fields is believed to be responsible for the observed x-ray fluxes from non-thermal electrons produced in astrophysical shocks. Here we present PIC simulations of plasma flows colliding with magnetized obstacles showing the formation of a bow shock and the consequent development of LHT. The plasma and obstacle parameters are chosen in order to reproduce the results obtained in a recent experiment conducted at the LULI laser facility at Ecole Polytechnique (France) to study accelerated electrons via LHT. The wave and particle spectra are studied and used to produce synthetic diagnostics that show good qualitative agreement with experimental results. Work supported by the European Research Council (Accelerates ERC-2010-AdG 267841).

  6. Composite Hybrid Cluster Built from the Integration of Polyoxometalate and a Metal Halide Cluster: Synthetic Strategy, Structure, and Properties.

    Science.gov (United States)

    Li, Xin-Xiong; Ma, Xiang; Zheng, Wen-Xu; Qi, Yan-Jie; Zheng, Shou-Tian; Yang, Guo-Yu

    2016-09-06

    A step-by-step synthetic strategy, setting up a bridge between the polyoxometalate (POM) and metal halide cluster (MHC) systems, is demonstrated to construct an unprecedented composite hybrid cluster built up from one high-nuclearity cationic MHC [Cu8I6](2+) and eight Anderson-type anionic POMs [HCrMo6O18(OH)6](2-) cross-linked by a tripodal alcohol derivative.

  7. Novel bio-synthetic hybrid materials and coculture systems for musculoskeletal tissue engineering

    Science.gov (United States)

    Lee, Hyeseung Janice

    Tissue Engineering is a truly exciting field of this age, trying to regenerate and repair impaired tissues. Unlike the old artificial implants, tissue engineering aims at making a long-term functional biological replacement. One strategy for such tissue engineering requires the following three components: cells, scaffolds, and soluble factors. Cells are cultured in a three-dimensional (3D) scaffold with medium containing various soluble factors. Once a tissue is developed in vitro, then it is implanted in vivo. The overall goal of this thesis was to develop novel bio-synthetic hybrid scaffolds and coculture system for musculoskeletal tissue engineering. The most abundant cartilage extracellular matrix (ECM) components are collagen and glycosaminoglycan (GAG), which are the natural scaffold for chondrocytes. As two different peptides, collagen mimetic peptide (CMP) and hyaluronic acid binding peptide (HABPep) were previously shown to bind to collagen and hyaluronic acid (HA) of GAG, respectively, it was hypothesized that immobilizing CMP and HABP on 3D scaffold would results in an interaction between ECM components and synthetic scaffolds via peptide-ECM bindings. CMP or HABPep-conjugated photopolymerizable poly(ethylene oxide) diacrylate (PEODA) hydrogels were synthesized and shown to retain encapsulated collagen or HA, respectively. This result supported that conjugated CMP and HABPep can interact with collagen and HA, respectively, and can serve as biological linkers in 3D synthetic hydrogels. When chondrocytes or mesenchymal stem cells (MSCs) were seeded, cells in CMP-conjugated scaffolds produced significantly more amount of type II collagen and GAG, compared to those in control scaffolds. Moreover, MSCs cultured in CMP-conjugated scaffolds exhibited lower level of hypertrophic markers, cbfa-1 and type X collagen. These results demonstrated that enhanced interaction between collagen and scaffold via CMP improves chondrogenesis of chondrocytes and MSCs and

  8. Tubular organ epithelialisation

    Directory of Open Access Journals (Sweden)

    Rhea Saksena

    2016-12-01

    Full Text Available Hollow, tubular organs including oesophagus, trachea, stomach, intestine, bladder and urethra may require repair or replacement due to disease. Current treatment is considered an unmet clinical need, and tissue engineering strategies aim to overcome these by fabricating synthetic constructs as tissue replacements. Smart, functionalised synthetic materials can act as a scaffold base of an organ and multiple cell types, including stem cells can be used to repopulate these scaffolds to replace or repair the damaged or diseased organs. Epithelial cells have not yet completely shown to have efficacious cell–scaffold interactions or good functionality in artificial organs, thus limiting the success of tissue-engineered grafts. Epithelial cells play an essential part of respective organs to maintain their function. Without successful epithelialisation, hollow organs are liable to stenosis, collapse, extensive fibrosis and infection that limit patency. It is clear that the source of cells and physicochemical properties of scaffolds determine the successful epithelialisation. This article presents a review of tissue engineering studies on oesophagus, trachea, stomach, small intestine, bladder and urethral constructs conducted to actualise epithelialised grafts.

  9. Cloned polynucleotide and synthetic oligonucleotide probes used in colony hybridization are equally efficient in the identification of enterotoxigenic Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Sommerfelt, H.; Kalland, K.H.; Raj, P.; Moseley, S.L.; Bhan, M.K.; Bjorvatn, B.

    1988-11-01

    Restriction endonuclease-generated polynucleotide and synthetically produced oligonucleotide gene probes used in colony hybridization assays proved to be efficient for the detection and differentiation of enterotoxigenic Escherichia coli. To compare their relative efficiencies, these two sets of probes were radiolabeled with /sup 32/P and were applied to 74 strains of E. coli with known enterotoxin profiles and to 156 previously unexamined E. coli isolates. The enterotoxigenic bacteria Vibrio cholerae O1, Vibrio cholerae non-O1 (NAG), Yersinia enterocolitica, and E. coli harboring the plasmid vectors of the polynucleotide gene probes were examined for further evaluation of probe specificity. The two classes of probes showed a perfect concordance in their specific detection and differentiation of enterotoxigenic E. coli. In the analysis of six strains, the signal strength on autoradiography after hybridization with oligonucleotides was weaker than that obtained after hybridization with polynucleotide probes. The probes did not hybridize with DNA from V. cholerae O1, V. cholerae non-O1 (NAG), or Y. enterocolitica. The strains of E. coli harboring the plasmid vectors of the polynucleotide gene probes were, likewise, negative in the hybridization assays.

  10. High Specific Selectivity and Membrane-Active Mechanism of Synthetic Cationic Hybrid Antimicrobial Peptides Based on the Peptide FV7.

    Science.gov (United States)

    Tan, Tingting; Wu, Di; Li, Weizhong; Zheng, Xin; Li, Weifen; Shan, Anshan

    2017-02-06

    Hybrid peptides integrating different functional domains of peptides have many advantages, such as remarkable antimicrobial activity, lower hemolysis and ideal cell selectivity, compared with natural antimicrobial peptides. FV7 (FRIRVRV-NH₂), a consensus amphiphilic sequence was identified as being analogous to host defense peptides. In this study, we designed a series of hybrid peptides FV7-LL-37 (17-29) (FV-LL), FV7-magainin 2 (9-21) (FV-MA) and FV7-cecropin A (1-8) (FV-CE) by combining the FV7 sequence with the small functional sequences LL-37 (17-29) (LL), magainin 2 (9-21) (MA) and cecropin A (1-8) (CE) which all come from well-described natural peptides. The results demonstrated that the synthetic hybrid peptides, in particular FV-LL, had potent antibacterial activities over a wide range of Gram-negative and Gram-positive bacteria with lower hemolytic activity than other peptides. Furthermore, fluorescent spectroscopy indicated that the hybrid peptide FV-LL exhibited marked membrane destruction by inducing outer and inner bacterial membrane permeabilization, while scanning electron microscopy (SEM) and transmission electron microscopy (TEM) demonstrated that FV-LL damaged membrane integrity by disrupting the bacterial membrane. Inhibiting biofilm formation assays also showed that FV-LL had similar anti-biofilm activity compared with the functional peptide sequence FV7. Synthetic cationic hybrid peptides based on FV7 could provide new models for combining different functional domains and demonstrate effective avenues to screen for novel antimicrobial agents.

  11. High Specific Selectivity and Membrane-Active Mechanism of Synthetic Cationic Hybrid Antimicrobial Peptides Based on the Peptide FV7

    Science.gov (United States)

    Tan, Tingting; Wu, Di; Li, Weizhong; Zheng, Xin; Li, Weifen; Shan, Anshan

    2017-01-01

    Hybrid peptides integrating different functional domains of peptides have many advantages, such as remarkable antimicrobial activity, lower hemolysis and ideal cell selectivity, compared with natural antimicrobial peptides. FV7 (FRIRVRV-NH2), a consensus amphiphilic sequence was identified as being analogous to host defense peptides. In this study, we designed a series of hybrid peptides FV7-LL-37 (17–29) (FV-LL), FV7-magainin 2 (9–21) (FV-MA) and FV7-cecropin A (1–8) (FV-CE) by combining the FV7 sequence with the small functional sequences LL-37 (17–29) (LL), magainin 2 (9–21) (MA) and cecropin A (1–8) (CE) which all come from well-described natural peptides. The results demonstrated that the synthetic hybrid peptides, in particular FV-LL, had potent antibacterial activities over a wide range of Gram-negative and Gram-positive bacteria with lower hemolytic activity than other peptides. Furthermore, fluorescent spectroscopy indicated that the hybrid peptide FV-LL exhibited marked membrane destruction by inducing outer and inner bacterial membrane permeabilization, while scanning electron microscopy (SEM) and transmission electron microscopy (TEM) demonstrated that FV-LL damaged membrane integrity by disrupting the bacterial membrane. Inhibiting biofilm formation assays also showed that FV-LL had similar anti-biofilm activity compared with the functional peptide sequence FV7. Synthetic cationic hybrid peptides based on FV7 could provide new models for combining different functional domains and demonstrate effective avenues to screen for novel antimicrobial agents. PMID:28178190

  12. Reliability of Tubular Joints

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    of the test is partly to obtain empirical data for the ultimate load-carrying capacity of tubular T-joints and partly to obtain some experience in performing tests with tubular joints. It is well known that tubular joints are usually designed in offshore engineering on the basis of empirical formulas obtained...

  13. Recent progress in the development of synthetic hybrids of natural or unnatural bioactive compounds for medicinal chemistry.

    Science.gov (United States)

    Tsogoeva, Svetlana B

    2010-08-01

    The present mini-review highlights the recent developments on different classes of synthetic hybrids of natural and/or unnatural bioactive compounds, the utilization of which is very promising, as distinct features of each component can be hybridized and their properties leveraged. Particular stress is put on the respective mode of action and the corresponding rationale behind covalent combinations of various bioactive agents to increase their therapeutic potential, facilitate their administration, to reduce harmful side effects and/or to overcome the problem of multi-drug resistance. This rather recent approach has already found applications in the development of new anti-cancer, anti-Alzheimer, anti-malaria, anti-microbial therapeutics and other novel compounds with unprecedented bioactivity.

  14. Enantiomers Recognition of Propranolol Based on Organic-Inorganic Hybrid Open-Tubular MIPs-CEC Column Using 3-(Trimethoxysilyl)Propyl Methacrylate as a Cross-Linking Monomer.

    Science.gov (United States)

    Chen, Guo-Ning; Li, Ning; Luo, Tian; Dong, Yu-Ming

    2017-01-10

    In this study, 3-(trimethoxysilyl)propyl methacrylate (γ-MPS), a bifunctional group compound, was used as a single cross-linking agent to prepare molecular imprinted inorganic-organic hybrid polymers by in situ polymerization for open-tubular capillary electro chromatography (CEC) column. The optimal preparation conditions were: the ratio between template molecule and functional monomer was 1:4; the volume proportion of porogen toluene and methanol was 1:1 and the volume of cross-linking agent γ-MPS was 69 μL. The optimal separation conditions were separation voltage of 15 kV; detection wavelength at 215 nm and background electrolyte composed of 70% acetonitrile/20 mmol/L boric acid salt (pH 6.9). Under the optimized conditions, the propranolol enantiomers can be separated well by CEC. The method is simple and fast, it can be a potentially useful approach for propranolol enantiomers separation.

  15. Simultaneous visualization of different genomes (J, JSt and St) in a Thinopyrum intermedium × Thinopyrum ponticum synthetic hybrid (Poaceae) and in its parental species by multicolour genomic in situ hybridization (mcGISH).

    Science.gov (United States)

    Kruppa, Klaudia; Molnár-Láng, Márta

    2016-01-01

    Multicolour genomic in situ hybridization (mcGISH) using total genomic DNA probes from Thinopyrum bessarabicum (Săvulescu & Rayss, 1923) Á. Löve, 1984 (genome J(b) or E(b), 2n = 14), and Pseudoroegneria spicata (Pursh, 1814) Á. Löve, 1980 (genome St, 2n = 14) was used to characterize the mitotic metaphase chromosomes of a synthetic hybrid of Thinopyrum intermedium (Host, 1805) Barkworth & D.R. Dewey, 1985 and Thinopyrum ponticum (Podpěra, 1902) Z.-W. Liu et R.-C.Wang, 1993 named "Agropyron glael" and produced by N.V. Tsitsin in the former Soviet Union. The mcGISH pattern of this synthetic hybrid was compared to its parental wheatgrass species. Hexaploid Thinopyrum intermedium contained 19 J, 9 J(St) and 14 St chromosomes. The three analysed Thinopyrum ponticum accessions had different chromosome compositions: 43 J + 27 J(St) (PI531737), 40 J + 30 J(St) (VIR-44486) and 38 J + 32 J(St) (D-3494). The synthetic hybrid carried 18 J, 28 J(St) and 8 St chromosomes, including one pair of J-St translocation and/or decreased fluorescent intensity, resulting in unique hybridization patterns. Wheat line Mv9kr1 was crossed with the Thinopyrum intermedium × Thinopyrum ponticum synthetic hybrid in Hungary in order to transfer its advantageous agronomic traits (leaf rust and yellow rust resistance) into wheat. The chromosome composition of a wheat/A.glael F1 hybrid was 21 wheat + 28 wheatgrass (11 J + 14 J(St)+ 3 S). In the present study, mcGISH involving the simultaneous use of St and J genomic DNA as probes provided information about the type of Thinopyrum chromosomes in a Thinopyrum intermedium/Thinopyrum ponticum synthetic hybrid called A. glael.

  16. Chitosan-graft-poly(n-butyl acrylate) copolymer: Synthesis and characterization of a natural/synthetic hybrid material.

    Science.gov (United States)

    Anbinder, Pablo; Macchi, Carlos; Amalvy, Javier; Somoza, Alberto

    2016-07-10

    Two chitosan polymers with different deacetylation degree and molecular weight were subjected to grafting reactions with the aim to enhance the properties of these bio-based materials. Specifically, n-butyl acrylate in different proportions was grafted onto two different deacetylation degree (DD%) chitosan using radical initiation in a surfactant free emulsion system. Infrared spectroscopy was used to confirm grafting and products grafting percentage and efficiency were evaluated against acrylate/chitosan ratio and DD%. Thermal and structural properties and the behavior against water of the raw and grafted biopolymers were studied using several experimental techniques: differential scanning calorimetry, transmission electron microscopy, dynamic light scattering, water swelling, contact angle and positron annihilation lifetime spectroscopy. The influence of the grafting process on the morphological and physicochemical properties of the prepared natural/synthetic hybrid materials is discussed.

  17. Hybrid PET/CT for noninvasive pharmacokinetic evaluation of dynamic PolyConjugates, a synthetic siRNA delivery system.

    Science.gov (United States)

    Mudd, Sarah R; Trubetskoy, Vladimir S; Blokhin, Andrei V; Weichert, Jamey P; Wolff, Jon A

    2010-07-21

    Positron emission tomography/computed tomography (PET/CT) hybrid imaging can be used to gain insights into a synthetic siRNA delivery system targeted to the liver. Either siRNA or the delivery vehicle was labeled with (64)Cu via 1, 4, 7, 10- tetraazacyclododecane- 1, 4, 7, 10- tetraacetic acid (DOTA) chelation. This study confirmed that the siRNA delivery system was successfully targeted to the liver. Incorporation of the siRNA into the delivery system protected the siRNA from renal filtration long enough so that the siRNA could be delivered to the liver. PET/CT imaging was important for confirming biodistribution and for determining differences in the distribution of labeled siRNA, siRNA incorporated into the delivery system, and the delivery system without siRNA.

  18. Multivariate synthetic streamflow generation using a hybrid model based on artificial neural networks

    Directory of Open Access Journals (Sweden)

    J. C. Ochoa-Rivera

    2002-01-01

    Full Text Available A model for multivariate streamflow generation is presented, based on a multilayer feedforward neural network. The structure of the model results from two components, the neural network (NN deterministic component and a random component which is assumed to be normally distributed. It is from this second component that the model achieves the ability to incorporate effectively the uncertainty associated with hydrological processes, making it valuable as a practical tool for synthetic generation of streamflow series. The NN topology and the corresponding analytical explicit formulation of the model are described in detail. The model is calibrated with a series of monthly inflows to two reservoir sites located in the Tagus River basin (Spain, while validation is performed through estimation of a set of statistics that is relevant for water resources systems planning and management. Among others, drought and storage statistics are computed and compared for both the synthetic and historical series. The performance of the NN-based model was compared to that of a standard autoregressive AR(2 model. Results show that NN represents a promising modelling alternative for simulation purposes, with interesting potential in the context of water resources systems management and optimisation. Keywords: neural networks, perceptron multilayer, error backpropagation, hydrological scenario generation, multivariate time-series..

  19. Human Serum Albumin Hybrid Incorporating Synthetic Hemes :A Novel O2-Carrying Hemoprotein

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Incorporation of synthetic heme (FeP) into recombinant human serum albumin(rHSA) provides an artificial hemoprotein(rHSA-FeP) which can bind and release oxygenreversibly under physiological conditions(in aqueous media, pH 7.3, 37 ℃) like hemoglobin(Hb) and myoglobin. An rHSA host absorbs maximally eight FeP molecules, and thesolution properties are almost identical to those of rHSA itself. The second-order structureand surface charge distribution of rHSA were always constant independent of the bindingnumbers of FeP. Its O2-binding ability satisfies the initial clinical requirements for red cellsubstitute. Although the NO-binding affinity is 8-fold high compared to the Hb's,administration of this fluid into rats showed negligible change in the blood pressure.Physiological responses to exchange transfusion with this rHSA-FeP into anaesthetized ratshave also been evaluated.

  20. Tubular apocrine adenoma.

    Science.gov (United States)

    Toribio, J; Zulaica, A; Peteiro, C

    1987-04-01

    We report a case of tubular apocrine adenoma located on the scalp, with characteristics of syringocystadenoma papilliferum in the superior part of the lesion. An interesting feature of the growth is its connective tissue involvement.

  1. Synthetic Ni3S2/Ni hybrid architectures as potential contrast agents in MRI

    Science.gov (United States)

    Ma, J.; Chen, K.

    2016-04-01

    Traditional magnetic resonance imaging (MRI) contrast agents mainly include superparamagnetic (SPM) iron oxide nanoparticle as T 2 contrast agent for liver and paramagnetic Gd (III)-chelate as T 1 contrast agent for all organs. In this work, weak ferromagnetic kale-like and SPM cabbage-like Ni3S2@Ni hybrid architectures were synthesized and evaluated as potential T 1 MRI contrast agents. Their relatively small r 2/r 1 ratios of 2.59 and 2.38, and high r 1 values of 11.27 and 4.89 mmol-1 L s-1 (for the kale-like and cabbage-like Ni3S2@Ni, respectively) will shed some light on the development of new-type MRI contrast agents.

  2. Hybrid Synthetic/Real Aperture Antenna for High Resolution Microwave Imaging

    Science.gov (United States)

    Doiron, Terence A.; Piepmeier, Jeffrey R.

    2003-01-01

    Observations of key hydrological parameters at the spatial and temporal scales required in the post-2002 era face significant technological challenges. These measurements are based on relatively low frequency thermal microwave emission (at 1.4 GHz for soil moisture and salinity, 10 GHz and up for precipitation, and 19 and 37 GHz for snow). The long wavelengths at these frequencies coupled with the high spatial and radiometric resolutions required by the various global hydrology missions necessitate the use of very large apertures. Two-dimensional Synthetic Thinned Array Radiometry (2-D STAR), though promising in the long term, has many technical challenges in the areas of power, and sensitivity for very large apertures (i.e. greater than 300 wavelengths). This paper will discuss an alternative approach to the pure 2-D STAR, which uses an offset parabolic cylinder reflector fed by multiple elements to form a 1-D STAR. In essence a single STAR element is composed of a feedhorn and parabolic cylinder reflector. The elements are sparsely arrayed and thus can share a single reflector. This antenna would have no moving parts once deployed, have much higher sensitivity than a Y-shaped 2-D STAR of equivalent size, many fewer receivers than that 2-D STAR, and the reflector could be made of a thin film and lightweight deployment system for high packing density. The instrument using this approach would be a cross track push broom imager. An overview of the design parameters, potential deployment mechanisms and applications will be presented.

  3. Hybrid Synthetic/Real Aperture Antenna for High Resolution Microwave Imaging

    Science.gov (United States)

    Doiron, Terence A.; Piepmeier, Jeffrey R.

    2003-01-01

    Observations of key hydrological parameters at the spatial and temporal scales required in the post-2002 era face significant technological challenges. These measurements are based on relatively low frequency thermal microwave emission (at 1.4 GHz for soil moisture and salinity, 10 GHz and up for precipitation, and 19 and 37 GHz for snow). The long wavelengths at these frequencies coupled with the high spatial and radiometric resolutions required by the various global hydrology missions necessitate the use of very large apertures. Two-dimensional Synthetic Thinned Array Radiometry (2-D STAR), though promising in the long term, has many technical challenges in the areas of power, and sensitivity for very large apertures (i.e. greater than 300 wavelengths). This paper will discuss an alternative approach to the pure 2-D STAR, which uses an offset parabolic cylinder reflector fed by multiple elements to form a 1-D STAR. In essence a single STAR element is composed of a feedhorn and parabolic cylinder reflector. The elements are sparsely arrayed and thus can share a single reflector. This antenna would have no moving parts once deployed, have much higher sensitivity than a Y-shaped 2-D STAR of equivalent size, many fewer receivers than that 2-D STAR, and the reflector could be made of a thin film and lightweight deployment system for high packing density. The instrument using this approach would be a cross track push broom imager. An overview of the design parameters, potential deployment mechanisms and applications will be presented.

  4. A hybrid sorption - Spectrometric method for determination of synthetic anionic dyes in foodstuffs.

    Science.gov (United States)

    Tikhomirova, Tatyana I; Ramazanova, Gyulselem R; Apyari, Vladimir V

    2017-04-15

    A sorption-spectrometric method for determination of the anionic synthetic dyes based on their sorption on silica sorbent modified with hexadecyl groups (C16) followed by measuring the diffuse reflectance spectra on the surface of the sorbent has been proposed. Adsorption of sulfonated azo dyes Tartrazine (E102), Sunset Yellow FCF (E110), Ponceau 4R (E124) reaches maximum in acidic medium (1M HCl - pH 1). For the quinophthalone type dye Quinoline Yellow (E104), the adsorption is also maximal in an acidic medium (1M HCl - pH 2). The triphenylmethane dye Fast Green FCF (E143) is absorbed in the wider area of pH (1M HCl - pH 6). Increasing concentration of the dyes in a solution led to the increase in absorption band intensity in diffuse reflectance spectra of the adsorbent, which was used for their direct determination. The proposed method was applied to the determination of dyes in beverages and pharmaceuticals.

  5. Synthetically Control of a Hybrid PV/FC/SC Power System for Stand-Alone Applications

    Directory of Open Access Journals (Sweden)

    Dakang Zhu

    2013-02-01

    Full Text Available In this study, a simple and practical control scheme for power assignment and load-following of a Hybrid Power System (HPS is proposed. The system consists of Photovoltaic (PV, Fuel Cell (FC, Super-Capacitor (SC, dc load, ac load and different kinds of converters. PV is chosen as a prior source, which normally operates in Maximum Power Point Tracking (MPPT mode. In order to achieve 24 h power supply under various natural conditions, FC is used as a backup source to provide the power deficit between solar generation and load demand. Taking the slow FC system dynamics into account, FC power slope has been limited to protect FC from fuel starvation, whereas SC is chosen to satisfy the requirement of the sudden load and solar radiation changes. Besides, a V/f controller is designed to meet ac load demand, while keeping the voltage and frequency within an acceptable range. All the details of this study, including system structure, control diagrams and MATLAB simulation results, are presented.

  6. Espirales tubulares para turbinas

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1958-07-01

    Full Text Available Para el suministro y fabricación de las espirales tubulares que debían alimentar las turbinas del aprovechamiento hidroeléctrico de Brownlee, que constituye el primero de los cuatro saltos del grupo Hells Canyon, del río Snake, la conocida factoría S. Morgan Smith, especializada en la construcción de turbinas y material a ellas accesorio, se encargó del estudio, fabricación y montaje de cuatro de estas espirales tubulares de 5,50 m de diámetro máximo.

  7. Targeted analysis with benchtop quadrupole–orbitrap hybrid mass spectrometer: Application to determination of synthetic hormones in animal urine

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Praveen [Departament de Química Analítica, Universitat de Barcelona, Barcelona (Spain); Rúbies, Antoni; Centrich, Francesc [Laboratori Agència Salut Pública de Barcelona, Barcelona (Spain); CIBER of Epidemiology and Public Health (CIBERESP), Madrid (Spain); Granados, Mercè [Departament de Química Analítica, Universitat de Barcelona, Barcelona (Spain); Cortés-Francisco, Nuria; Caixach, Josep [Mass Spectrometry Laboratory-Organic Pollutants, IDAEA-CSIC, Barcelona (Spain); Companyó, Ramon, E-mail: compano@ub.edu [Departament de Química Analítica, Universitat de Barcelona, Barcelona (Spain)

    2013-05-30

    Graphical abstract: -- Highlights: •The quadrupole in Q Exactive acts as a powerful filter to reduce ion suppression. •Reducing mass range using quadrupole in targeted modes increases the S/N ratio. •Targeted SIM data dependent scan modes are the most suitable for residue analysis. •A HRMS confirmatory method for synthetic hormones in urine has been developed. •The Q Exactive provides similar sensitivity and enhanced selectivity compared to QqQ. -- Abstract: Sensitive and unequivocal determination of analytes/contaminants in complex matrices is a challenge in the field of food safety control. In this study, various acquisition modes (Full MS/AIF, Full MS + tMS/MS, Full MS/dd MS/MS and tSIM/ddMS/MS) and parameters of a quadrupole–orbitrap hybrid mass spectrometer (Q Exactive) were studied in detail. One of the main conclusions has been that, reducing the scan range for Full MS (using the quadrupole) and targeted modes give higher signal-to-noise (S/N) ratios and thereby better detection limits for analytes in matrix. The use of Q Exactive in a complex case, for the confirmatory analysis of hormones in animal urine is presented. A targeted SIM data dependent MS/MS (tSIM/ddMS/MS) acquisition method for determination of eight synthetic hormones (trenbolone, 17α ethinylestradiol, zeranol, stanozolol, dienestrol, diethylstilbestrol, hexestrol, taleranol) and a naturally occurring hormone (zearalenone) in animal urine were optimized to have sensitive precursors from targeted SIM mode and trigger MS/MS scans over the entire chromatograph peak. The method was validated according to EC/657/2002. CCα (decision limit) for the analytes ranged between 0.11 μg L{sup −1} and 0.69 μg L{sup −1} and CCβ (detection capability) ranged between 0.29 μg L{sup −1} and 0.90 μg L{sup −1}.

  8. Markers of tubular dysfunction.

    Science.gov (United States)

    Piscator, M

    1989-03-01

    Since the first description of tubular proteinuria in 1958, much progress has been made with regard to diagnostic means for detecting small changes in the function of the proximal tubule. Small increases in the excretion of low-molecular-weight proteins can now be determined with great accuracy. Determination of total protein is an economic way of screening large populations but does not give specific information on the type of damage. Determinations of glucose, phosphate and amino acids are relatively insensitive methods, since their excretion is also dependent on diet and nutritional status. Determination of high-molecular-weight enzymes released from damaged tubular cells may be of use for studies of acute as well as chronic effects of nephrotoxic agents, but more data are needed.

  9. Impact of Hybrid Instruction on Student Achievement in Post-Secondary Institutions: A Synthetic Review of the Literature

    Science.gov (United States)

    Lamport, Mark A.; Hill, Randy J.

    2012-01-01

    Hybrid online instruction is a cross between traditional face-to-face classroom format and online-only instruction. The premise behind hybrid instruction is that it provides the benefits of personal interaction with the convenience and flexibility of online assignments and discussions. While there has been significant research on how students…

  10. Reproductive, Growth Performance and Nutrient Utilization of Heterobranchus bidorsalis (Geoffroy, 1809 and its Hybrid Clariabranchus Induced with Synthetic Hormone and Pituitary Gland of Heterobranchus bidorsalis

    Directory of Open Access Journals (Sweden)

    M.A. Anetekhai

    2011-01-01

    Full Text Available This study was conducted to assess the reproductive performance, growth rate and nutrient utilization capacities of pure breed Heterobranchus bidorsalis (H. bidorsalis ? x H. bidorsalis ? and its hybrid (H. bidorsalis ? x C. gariepinus ? (Clariabranchus induced with synthetic hormone (ovaprim and pituitary of male and female Heterobranchus bidorsalis. In this study, 3 female Heterobranchus bidorsalis, 3 male Heterobranchus bidorsalis and 3 male Clarias gariepinus were used for the experiment. One female H. bidorsalis induced with ovaprim produced eggs which were divided into two equal halves. Each half was fertilized separately by milt from H. bidorsalis and C. gariepinus to produce pure breed and hybrid, respectively. A similar crossing was done for the female H. bidorsalis induced with Male Pituitary Extract (MPE and Female Pituitary Extract (FPE. Percentage fertilization and hatching rate of pure breed induced with ovaprim were significantly (p<0.05 higher than the other genetic crosses. The highest values for weight gain (5.461.58 g, average daily growth (0.390.11 g and specific growth rate (1.040.16%/day occurred in pure breed induced with MPE. The lowest values for these growth parameters were obtained in the hybrid induced with FPE. Feed intake, protein intake, feed conversion ratio and protein efficiency ratio varied significantly (p<0.05 among the treatments. This study has shown that the pure breeds and hybrids induced with ovaprim and MPE performed better than those induced with FPE. Therefore, they are recommended for commercial aquaculture.

  11. Improved antimicrobial activities of synthetic-hybrid bacteriocins designed from enterocin E50-52 and pediocin PA-1.

    Science.gov (United States)

    Tiwari, Santosh Kumar; Sutyak Noll, Katia; Cavera, Veronica L; Chikindas, Michael L

    2015-03-01

    Two hybrid bacteriocins, enterocin E50-52/pediocin PA-1 (EP) and pediocin PA-1/enterocin E50-52 (PE), were designed by combining the N terminus of enterocin E50-52 and the C terminus of pediocin PA-1 and by combining the C terminus of pediocin PA-1 and the N terminus of enterocin E50-52, respectively. Both hybrid bacteriocins showed reduced MICs compared to those of their natural counterparts. The MICs of hybrid PE and EP were 64- and 32-fold lower, respectively, than the MIC of pediocin PA-1 and 8- and 4-fold lower, respectively, than the MIC of enterocin E50-52. In this study, the effect of hybrid as well as wild-type (WT) bacteriocins on the transmembrane electrical potential (ΔΨ) and their ability to induce the efflux of intracellular ATP were investigated. Enterocin E50-52, pediocin PA-1, and hybrid bacteriocin PE were able to dissipate ΔΨ, but EP was unable to deplete this component. Both hybrid bacteriocins caused a loss of the intracellular concentration of ATP. EP, however, caused a faster efflux than PE and enterocin E50-52. Enterocin E50-52 and hybrids PE and EP were active against the Gram-positive and Gram-negative bacteria tested, such as Micrococcus luteus, Salmonella enterica serovar Enteritidis 20E1090, and Escherichia coli O157:H7. The hybrid bacteriocins designed and described herein are antimicrobial peptides with MICs lower those of their natural counterparts. Both hybrid peptides induce the loss of intracellular ATP and are capable of inhibiting Gram-negative bacteria, and PE dissipates the electrical potential. In this study, the MIC of hybrid bacteriocin PE decreased 64-fold compared to the MIC of its natural peptide counterpart, pediocin PA-1. Inhibition of Gram-negative pathogens confers an additional advantage for the application of these peptides in therapeutics.

  12. Separation of BSA through FAU-Type Zeolite Ceramic-Composite Membrane Formed on Tubular Ceramic Support: Optimization of Process Parameters by Hybrid Response Surface Methodology and Bi-Objective Genetic Algorithm.

    Science.gov (United States)

    Kumar, R Vinoth; Moorthy, I Ganesh; Pugazhenthi, G

    2017-03-09

    In this study, Faujasite (FAU) zeolite was coated on low cost tubular ceramic support as a separating layer via hydrothermal route. The mixture of silicate and aluminate solutions was used to create a zeolitic separation layer on the support. The prepared zeolite ceramic-composite membrane was characterized by using X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), particle size distribution (PSD), Field emission scanning electron microscopy (FESEM) and zeta potential measurements. The porosity of ceramic support (53%) was reduced by the deposition of FAU (43%) zeolite layer. The pore size and water permeability of the membrane were evaluated as 0.179 µm and 1.62 × 10(-7) m(3)/m(2)s.kPa, respectively, which are lower than that of the support (pore size of 0.309 µm and water permeability of 5.93 × 10(-7) m(3)/m(2)s.kPa). The permeate flux and rejection potential of the prepared membrane was evaluated by microfiltration of bovine serum albumin (BSA). To study the influences of three independent variables such as operating pressure (68.94 - 275.79 kPa), concentration of BSA (100 - 500 ppm) and solution pH (2 - 4) on permeate flux and percentage of rejection, the RSM (Response Surface Methodology) was employed. The predicted models for permeate flux and rejection were further subjected to bi-objective Genetic Algorithm (GA). The hybrid RSM-GA approach resulted a maximum permeate flux of 2.66 × 10(-5) m(3)/m(2)s and BSA rejection of 88.02%, at which the optimum conditions were attained as 100 ppm BSA concentration, 2 pH solution and 275.79 kPa applied pressure. In addition, the separation efficiency was compared with other membranes applied for BSA separation in order to know the potential of the fabricated FAU zeolite ceramic-composite membrane.

  13. Hybrid Broadband Ground-Motion Simulations: Combining Long-Period Deterministic Synthetics with High-Frequency Multiple S-to-S Backscattering

    KAUST Repository

    Mai, Paul Martin

    2010-09-20

    We present a new approach for computing broadband (0-10 Hz) synthetic seismograms by combining high-frequency (HF) scattering with low-frequency (LF) deterministic seismograms, considering finite-fault earthquake rupture models embedded in 3D earth structure. Site-specific HF-scattering Green\\'s functions for a heterogeneous medium with uniformly distributed random isotropic scatterers are convolved with a source-time function that characterizes the temporal evolution of the rupture process. These scatterograms are then reconciled with the LF-deterministic waveforms using a frequency-domain optimization to match both amplitude and phase spectra around the target intersection frequency. The scattering parameters of the medium, scattering attenuation ηs, intrinsic attenuation ηi, and site-kappa, as well as frequency-dependent attenuation, determine waveform and spectral character of the HF-synthetics and thus affect the hybrid broadband seismograms. Applying our methodology to the 1994 Northridge earthquake and validating against near-field recordings at 24 sites, we find that our technique provides realistic broadband waveforms and consistently reproduces LF ground-motion intensities for two independent source descriptions. The least biased results, compared to recorded strong-motion data, are obtained after applying a frequency-dependent site-amplification factor to the broadband simulations. This innovative hybrid ground-motion simulation approach, applicable to any arbitrarily complex earthquake source model, is well suited for seismic hazard analysis and ground-motion estimation.

  14. Synthetic surfactant- and cross-linker-free preparation of highly stable lipid-polymer hybrid nanoparticles as potential oral delivery vehicles.

    Science.gov (United States)

    Wang, Taoran; Xue, Jingyi; Hu, Qiaobin; Zhou, Mingyong; Chang, Chao; Luo, Yangchao

    2017-06-05

    The toxicity associated with concentrated synthetic surfactants and the poor stability at gastrointestinal condition are two major constraints for practical applications of solid lipid nanoparticles (SLN) as oral delivery vehicles. In this study, a synthetic surfactant-free and cross-linker-free method was developed to fabricate effective, safe, and ultra-stable lipid-polymer hybrid nanoparticles (LPN). Bovine serum albumin (BSA) and dextran varying in molecular weights were first conjugated through Maillard reaction and the conjugates were exploited to emulsify solid lipid by a solvent diffusion and sonication method. The multilayer structure was formed by self-assembly of BSA-dextran micelles to envelope solid lipid via a pH- and heating-induced facile process with simultaneous surface deposition of pectin. The efficiency of different BSA-dextran conjugates was systematically studied to prepare LPN with the smallest size, the most homogeneous distribution and the greatest stability. The molecular interactions were characterized by Fourier transform infrared and fluorescence spectroscopies. Both nano spray drying and freeze-drying methods were tested to produce spherical and uniform pectin-coated LPN powders that were able to re-assemble nanoscale structure when redispersed in water. The results demonstrated the promise of a synthetic surfactant- and cross-linker-free technique to prepare highly stable pectin-coated LPN from all natural biomaterials as potential oral delivery vehicles.

  15. Morphological, cytological and molecular analyses of a synthetic hexaploid derived from an interspecific hybrid between Gossypium hirsutum and Gossypium anomalum

    Directory of Open Access Journals (Sweden)

    Xia Zhang

    2014-10-01

    Full Text Available Gossypium anomalum represents an inestimable source of genes that could potentially be transferred into the gene pool of cultivated cotton. To resolve interspecific hybrid sterility problems, we previously treated triploid hybrids derived from a cross between Gossypium hirsutum and G. anomalum with 0.15% colchicine and obtained a putative fertile hexaploid. In this study, we performed morphological, molecular and cytological analyses to assess the hybridity and doubled status of putative interspecific hybrid plants. Most of the morphological characteristics of the putative hexaploid plants were intermediate between G. hirsutum and G. anomalum. Analysis of mitotic metaphase plates revealed 78 chromosomes, confirming the doubled hybrid status of the hexaploid. Genome-wide molecular analysis with different genome-derived SSR markers revealed a high level of polymorphism (96.6% between G. hirsutum and G. anomalum. The marker transferability rate from other species to G. anomalum was as high as 98.0%. The high percentage of polymorphic markers with additive banding profiles in the hexaploid indicates the hybridity of the hexaploid on a genome-wide level. A-genome-derived markers were more powerful for distinguishing the genomic differences between G. hirsutum and G. anomalum than D-genome-derived markers. This study demonstrates the hybridity and chromosomally doubled status of the (G. anomalum × G. hirsutum2 hexaploid using morphological, cytological and molecular marker methods. The informative SSR markers screened in the study will be useful marker resources for tracking the flow of G. anomalum genetic material among progenies that may be produced by future backcrosses to G. hirsutum.

  16. Morphological, cytological and molecular analyses of a synthetic hexaploid derived from an interspecific hybrid between Gossypium hirsutum and Gossypium anomalum

    Institute of Scientific and Technical Information of China (English)

    Xia; Zhang; Caijiao; Zhai; Linchi; He; Qi; Guo; Xianggui; Zhang; Peng; Xu; Hongmei; Su; Yuanyong; Gong; Wanchao; Ni; Xinlian; Shen

    2014-01-01

    Gossypium anomalum represents an inestimable source of genes that could potentially be transferred into the gene pool of cultivated cotton. To resolve interspecific hybrid sterility problems, we previously treated triploid hybrids derived from a cross between Gossypium hirsutum and G. anomalum with 0.15% colchicine and obtained a putative fertile hexaploid. In this study, we performed morphological, molecular and cytological analyses to assess the hybridity and doubled status of putative interspecific hybrid plants. Most of the morphological characteristics of the putative hexaploid plants were intermediate between G. hirsutum and G.anomalum. Analysis of mitotic metaphase plates revealed 78 chromosomes, confirming the doubled hybrid status of the hexaploid. Genome-wide molecular analysis with different genome-derived SSR markers revealed a high level of polymorphism(96.6%) between G. hirsutum and G. anomalum. The marker transferability rate from other species to G. anomalum was as high as 98.0%. The high percentage of polymorphic markers with additive banding profiles in the hexaploid indicates the hybridity of the hexaploid on a genome-wide level. A-genome-derived markers were more powerful for distinguishing the genomic differences between G. hirsutum and G. anomalum than D-genome-derived markers. This study demonstrates the hybridity and chromosomally doubled status of the(G. anomalum × G. hirsutum)2hexaploid using morphological, cytological and molecular marker methods. The informative SSR markers screened in the study will be useful marker resources for tracking the flow of G. anomalum genetic material among progenies that may be produced by future backcrosses to G. hirsutum.

  17. Synthetic approaches, structure activity relationship and biological applications for pharmacologically attractive pyrazole/pyrazoline-thiazolidine-based hybrids.

    Science.gov (United States)

    Havrylyuk, Dmytro; Roman, Olexandra; Lesyk, Roman

    2016-05-04

    The features of the chemistry of 4-thiazolidinone and pyrazole/pyrazolines as pharmacologically attractive scaffolds were described in a number of reviews in which the main approaches to the synthesis of mentioned heterocycles and their biological activity were analyzed. However, the pyrazole/pyrazoline-thiazolidine-based hybrids as biologically active compounds is poorly discussed in the context of pharmacophore hybrid approach. Therefore, the purpose of this review is to summarize the data about the synthesis and modification of heterocyclic systems with thiazolidine and pyrazoline or pyrazole fragments in molecules as promising objects of modern bioorganic and medicinal chemistry. The description of biological activity was focused on SAR analysis and mechanistic insights of mentioned hybrids.

  18. Genome-Wide Gene Expressions Respond Differently to A-subgenome Origins in Brassica napus Synthetic Hybrids and Natural Allotetraploid

    Science.gov (United States)

    Zhang, Dawei; Pan, Qi; Tan, Chen; Zhu, Bin; Ge, Xianhong; Shao, Yujiao; Li, Zaiyun

    2016-01-01

    The young allotetraploid Brassica napus (2n = 38, AACC) is one of models to study genomic responses to allopolyploidization. The extraction of AA component from natural B. napus and then restitution of progenitor B. rapa should provide a unique opportunity to reveal the genome interplay for gene expressions during the evolution. Herein, B. napus hybrids (2n = 19, AC) between the extracted and extant B. rapa (2n = 20, AA) and the same B. oleracea genotype (2n = 18, CC) were studied by RNA-seq and compared with natural B. napus donor, to reveal the gene expression changes from hybridization and domestication and the effects of A genome with different origins. Upon the initial merger of two diploid genomes, additive gene expression was prevalent in these two hybrids, for non-additively expressed genes only represented a small portion of total expressed genes. A high proportion of genes exhibited expression level dominance, with no preference to either of the parental genomes. Comparison of homoeolog expressions also showed no bias toward any genomes and the parental expression patterns were often maintained in the hybrids and natural allotetraploids. Although, the overall patterns of gene expression were highly conserved between two hybrids, the extracted B. rapa responded less and appeared more compatible for hybridization than the extant B. rapa. Our results suggested that expression level dominance and homoeolog expressions bias were balanced at the initial stage of genome merger, and such balance were largely maintained during the domestication of B. napus, despite the increased extent over time. PMID:27790227

  19. Probing the local environment of hybrid materials designed from ionic liquids and synthetic clay by Raman spectroscopy

    Science.gov (United States)

    Siqueira, Leonardo J. A.; Constantino, Vera R. L.; Camilo, Fernanda F.; Torresi, Roberto M.; Temperini, Marcia L. A.; Ribeiro, Mauro C. C.; Izumi, Celly M. S.

    2014-03-01

    Hybrid organic-inorganic material containing Laponite clay and ionic liquids forming cations have been prepared and characterized by FT-Raman spectroscopy, X-ray diffraction, and thermal analysis. The effect of varying the length of the alkyl side chain and conformations of cations has been investigated by using different ionic liquids based on piperidinium and imidazolium cations. The structure of the N,N-butyl-methyl-piperidinium cation and the assignment of its vibrational spectrum have been further elucidated by quantum chemistry calculations. The X-ray data indicate that the organic cations are intercalated parallel to the layers of the clay. Comparison of Raman spectra of pure ionic liquids with different anions and the resulting solid hybrid materials in which the organic cations have been intercalated into the clay characterizes the local environment experienced by the cations in the hybrid materials. The Raman spectra of hybrid materials suggest that the local environment of all confined cations, in spite of this diversity in properties, resembles the liquid state of ionic liquids with a relatively disordered structure.

  20. Renal tubular acidosis.

    Science.gov (United States)

    Rothstein, M; Obialo, C; Hruska, K A

    1990-12-01

    Renal tubular acidosis refers to a group of disorders that result from pure tubular damage without concomitant glomerular damage. They could be hereditary (primary) or acquired (secondary to various disease states like sickle cell disease, obstructive uropathy, postrenal transplant, autoimmune disease, or drugs). The hallmark of the disorder is the presence of hyperchloremic metabolic acidosis with, or without, associated defects in potassium homeostasis, a UpH greater than 5.5 in the presence of systemic acidemia, and absence of an easily identifiable cause of the acidemia. There are three physiologic types whose basic defects are impairment of or a decrease in acid excretion, i.e., type 1 (dRTA); a failure in bicarbonate reabsorption, i.e., type 2 (pRTA); and deficiency of buffer or impaired generation of NH4+, i.e., type 4 RTA. Several pathophysiologic mechanisms have been postulated for these various types. pRTA is the least common of all in the adult population. It rarely occurs as an isolated defect. It is frequently accompanied by diffuse proximal tubule transport defects with aminoaciduria, glycosuria, hyperphosphaturia, and so forth (Fanconi syndrome). dRTA is associated with a high incidence of nephrolithiasis, nephrocalcinosis, osteodystrophy, and growth retardation (in children). Osteodystrophy also occurs in pRTA to a lesser degree and is believed to be secondary to hypophosphatemia. Patients with type 4 RTA usually have mild renal insufficiency from either diabetes mellitus or interstitial nephritis. Acute bicarbonate loading will result in a high fractional excretion of bicarbonate greater than 15% (FEHCO3- greater than 15%) in patients with pRTA, but FEHCO3- less than 3% in patients with dRTA. Type I patients will also have a low (U - B) PCO2 with bicarbonate loading. They are also unable to lower their urine pH to less than 5.5 with NH4Cl loading. The treatment of these patients involves avoidance of precipitating factors when possible, treatment

  1. General Construction of Tubular Geometry

    CERN Document Server

    Mukhopadhyay, Partha

    2016-01-01

    We consider the problem of locally describing tubular geometry around a submanifold embedded in a (pseudo)Riemannian manifold in its general form. Given the geometry of ambient space in an arbitrary coordinate system and equations determining the submanifold in the same system, we compute the tubular expansion coefficients in terms of this {\\it a priori data}. This is done by using an indirect method that crucially applies the tubular expansion theorem for vielbein previously derived. With an explicit construction involving the relevant coordinate and non-coordinate frames we verify consistency of the whole method up to quadratic order in vielbein expansion. Furthermore, we perform certain (long and tedious) higher order computation which verifies the first non-trivial spin connection term in the expansion for the first time. Earlier a similar method was used to compute tubular geometry in loop space. We explain this work in the light of our general construction.

  2. Synthetic Antenna Functioning As Light Harvester in the Whole Visible Region for Enhanced Hybrid Photosynthetic Reaction Centers.

    Science.gov (United States)

    Hassan Omar, Omar; la Gatta, Simona; Tangorra, Rocco Roberto; Milano, Francesco; Ragni, Roberta; Operamolla, Alessandra; Argazzi, Roberto; Chiorboli, Claudio; Agostiano, Angela; Trotta, Massimo; Farinola, Gianluca M

    2016-07-20

    The photosynthetic reaction center (RC) from the Rhodobacter sphaeroides bacterium has been covalently bioconjugated with a NIR-emitting fluorophore (AE800) whose synthesis was specifically tailored to act as artificial antenna harvesting light in the entire visible region. AE800 has a broad absorption spectrum with peaks centered in the absorption gaps of the RC and its emission overlaps the most intense RC absorption bands, ensuring a consistent increase of the protein optical cross section. The covalent hybrid AE800-RC is stable and fully functional. The energy collected by the artificial antenna is transferred to the protein via FRET mechanism, and the hybrid system outperforms by a noteworthy 30% the overall photochemical activity of the native protein under the entire range of visible light. This improvement in the optical characteristic of the photoenzyme demonstrates the effectiveness of the bioconjugation approach as a suitable route to new biohybrid materials for energy conversion, photocatalysis, and biosensing.

  3. Evidence of Genomic Exchanges between Homeologous Chromosomes in a Cross of Peanut with Newly Synthetized Allotetraploid Hybrids

    Science.gov (United States)

    Nguepjop, Joel R.; Tossim, Hodo-Abalo; Bell, Joseph M.; Rami, Jean-François; Sharma, Shivali; Courtois, Brigitte; Mallikarjuna, Nalini; Sane, Djibril; Fonceka, Daniel

    2016-01-01

    Cultivated peanut and synthetics are allotetraploids (2n = 4x = 40) with two homeologous sets of chromosomes. Meiosis in allotetraploid peanut is generally thought to show diploid-like behavior. However, a recent study pointed out the occurrence of recombination between homeologous chromosomes, especially when synthetic allotetraploids are used, challenging the view of disomic inheritance in peanut. In this study, we investigated the meiotic behavior of allotetraploid peanut using 380 SSR markers and 90 F2 progeny derived from the cross between Arachis hypogaea cv Fleur 11 (AABB) and ISATGR278-18 (AAKK), a synthetic allotetraploid that harbors a K-genome that was reported to pair with the cultivated B-genome during meiosis. Segregation analysis of SSR markers showed 42 codominant SSRs with unexpected null bands among some progeny. Chi-square tests for these loci deviate from the expected 1:2:1 Mendelian ratio under disomic inheritance. A linkage map of 357 codominant loci aligned on 20 linkage groups (LGs) with a total length of 1728 cM, averaging 5.1 cM between markers, was developed. Among the 10 homeologous sets of LGs, one set consisted of markers that all segregated in a polysomic-like pattern, six in a likely disomic pattern and the three remaining in a mixed pattern with disomic and polysomic loci clustered on the same LG. Moreover, we reported a substitution of homeologous chromosomes in some progeny. Our results suggest that the homeologous recombination events occurred between the A and K genomes in the newly synthesized allotetraploid and have been highlighted in the progeny. Homeologous exchanges are rarely observed in tetraploid peanut and have not yet been reported for AAKK and AABB genomes. The implications of these results on peanut breeding are discussed. PMID:27847512

  4. Evidence of genomic exchanges between homeologous chromosomes in a cross of peanut with newly synthetized allotetraploid hybrids

    Directory of Open Access Journals (Sweden)

    Joel Romaric Nguepjop

    2016-11-01

    Full Text Available Cultivated peanut and synthetics are allotetraploids (2n=4x=40 with two homeologous sets of chromosomes. Meiosis in allotetraploid peanut is generally thought to show diploid-like behavior. However, a recent study pointed out the occurrence of recombination between homeologous chromosomes, especially when synthetic allotetraploids are used, challenging the view of disomic inheritance in peanut. In this study, we investigated the meiotic behavior of allotetraploid peanut using 380 SSR markers and 90 F2 progeny derived from the cross between Arachis hypogaea cv Fleur 11 (AABB and ISATGR278-18 (AAKK, a synthetic allotetraploid that harbors a K-genome that was reported to pair with the cultivated B-genome during meiosis. Segregation analysis of SSR markers showed 42 codominant SSRs with unexpected null bands among some progeny. Chi-square tests for these loci deviate from the expected 1:2:1 Mendelian ratio under disomic inheritance. A linkage map of 357 codominant loci aligned on 20 linkage groups (LGs with a total length of 1728 cM, averaging 5.1 cM between markers, was developed. Among the ten homeologous sets of LGs, one set consisted of markers that all segregated in a polysomic-like pattern, 6 in a likely disomic pattern and the 3 remaining in a mixed pattern with disomic and polysomic loci clustered on the same LG. Moreover, we reported a substitution of homeologous chromosomes in some progeny. Our results suggest that the homeologous recombination events occurred between the A and K genomes in the newly synthesized allotetraploid and have been highlighted in the progeny. Homeologous exchanges are rarely observed in tetraploid peanut and have not yet been reported for AAKK and AABB genomes. The implications of these results on peanut breeding are discussed.

  5. Semi-synthesis of biologically active nisin hybrids composed of the native lanthionine ABC-fragment and a cross-stapled synthetic DE-fragment.

    Science.gov (United States)

    Slootweg, Jack C; Peters, Nienke; Quarles van Ufford, H Linda C; Breukink, Eefjan; Liskamp, Rob M J; Rijkers, Dirk T S

    2014-10-01

    The antimicrobial peptide nisin is a promising template for designing novel peptide-based antibiotics to improve its drug-like properties. First steps in that direction represent the synthesis of hybrid nisin derivatives that contain a native nisin ABC-part and synthesized cross-stapled DE-ring fragments and are described here. The biological activity of the newly synthesized nisin derivatives was evaluated in order to compare the bioactivity of the synthetic DE-ring containing mimic and native lanthionine-bridged DE-ring containing nisin. The native nisin ABC-ring system was obtained via chymotrypsin digestion of full-length nisin, and was subsequently functionalized at the C-terminal carboxylate with two different amino alkyne moieties. Next, nisin hybrids were successfully prepared using Cu(I)-catalyzed azide alkyne cycloaddition 'click' chemistry by chemo-selective ligation of the ABC-alkyne with the N-terminal azido functionalized dicarba-DE ring mimic. The newly synthesized compounds were active as potent lipid II binders and retained antimicrobial activity in a growth inhibition assay. However, pore formation was not observed, possibly either due to the different character of the 'staples' as compared to the parent sulfides, or due to the triazole moiety as a sub-optimal amide bond isostere.

  6. Macroporous nanowire nanoelectronic scaffolds for synthetic tissues

    Science.gov (United States)

    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.

  7. Reaction of Silane Alkoxide with Acid Anhydride as a Novel Synthetic Method for Organic-Inorganic Hybrid Materials

    Institute of Scientific and Technical Information of China (English)

    Masahiro Fujiwara

    2005-01-01

    @@ 1Introduction Sol-gel method is a potent method to produce new inorganic and organic-inorganic hybrid materials. The key step of this methodology is the hydrolysis of a metal alkoxide or other metal substrates such as acetylacetonates to form hydroxyl metal species, followed by their condensation to metal-oxygen-metal (M - O - M)bonds. In this process, the utilization of water, generally in excess, is essential and alcoholic solvents such as ethanol are often required to homogenize the solution when organic compounds coexist. As the common sol-gel method using water allows for limited uses of organic substrates due to their low solubility and stability in aqueous solution, modified variations of sol-gel method are required. Recently, some processes were reported for preparing metal oxides from metal alkoxides without the utilization of water.

  8. Tubular cystourethroneostomy after total prostatectomy.

    Science.gov (United States)

    Melchior, H

    1975-01-01

    After radical prostatectomy cystourethroneostomy is done as a tubular cystourethroplasty. In the last 13 months 14 patients have been operated on in this manner. In 12 patients continence was achieved; 2 patients had a temporary stress incontinence. The stress incontinence could be treated successfully by temporary electrostimulation of the pelvic floor by an anal plug stimulator.

  9. A Simple Tubular Reactor Experiment.

    Science.gov (United States)

    Hudgins, Robert R.; Cayrol, Bertrand

    1981-01-01

    Using the hydrolysis of crystal violet dye by sodium hydroxide as an example, the theory, apparatus, and procedure for a laboratory demonstration of tubular reactor behavior are described. The reaction presented can occur at room temperature and features a color change to reinforce measured results. (WB)

  10. Bioinspired coupled helical coils for soft tissue engineering of tubular structures - Improved mechanical behavior of tubular collagen type I templates.

    Science.gov (United States)

    Janke, H P; Bohlin, J; Lomme, R M L M; Mihaila, S M; Hilborn, J; Feitz, W F J; Oosterwijk, E

    2017-09-01

    The design of constructs for tubular tissue engineering is challenging. Most biomaterials need to be reinforced with supporting structures such as knittings, meshes or electrospun material to comply with the mechanical demands of native tissues. In this study, coupled helical coils (CHCs) were manufactured to mimic collagen fiber orientation as found in nature. Monofilaments of different commercially available biodegradable polymers were wound and subsequently fused, resulting in right-handed and left-handed polymer helices fused together in joints where the filaments cross. CHCs of different polymer composition were tested to determine the tensile strength, strain recovery, hysteresis, compressive strength and degradation of CHCs of different composition. Subsequently, seamless and stable hybrid constructs consisting of PDSII® USP 2-0 CHCs embedded in porous collagen type I were produced. Compared to collagen alone, this hybrid showed superior strain recovery (93.5±0.9% vs 71.1±12.6% in longitudinal direction; 87.1±6.6% vs 57.2±4.6% in circumferential direction) and hysteresis (18.9±2.7% vs 51.1±12.0% in longitudinal direction; 11.5±4.6% vs 46.3±6.3% in circumferential direction). Furthermore, this hybrid construct showed an improved Young's modulus in both longitudinal (0.5±0.1MPavs 0.2±0.1MPa; 2.5-fold) and circumferential (1.65±0.07MPavs (2.9±0.3)×10(-2)MPa; 57-fold) direction, respectively, compared to templates created from collagen alone. Moreover, hybrid template characteristics could be modified by changing the CHC composition and CHCs were produced showing a mechanical behavior similar to the native ureter. CHC-enforced templates, which are easily tunable to meet different demands may be promising for tubular tissue engineering. Most tubular constructs lack sufficient strength and tunability to comply with the mechanical demands of native tissues. Therefore, we embedded coupled helical coils (CHCs) produced from biodegradable polymers - to

  11. Early detection of tubular dysfunction.

    Science.gov (United States)

    Piscator, M

    1991-11-01

    The determination of low-molecular-weight proteins in urine as a tool for early detection of damage to the proximal tubules is briefly discussed. Beta 2-microglobulin, retinol-binding protein and alpha 1-microglobulin are at present the most widely used markers for tubular dysfunction. The determination of beta 2-microglobulin has earlier been the method of choice, but due to its instability at low pH there are certain disadvantages. Available data indicate that alpha 1-microglobulin may replace beta 2-microglobulin for screening purposes. The low-molecular-weight proteins are at present the best markers for early detection of tubular dysfunction; other constituents are not as well suited for this, even if the determination of urine enzymes has its supporters.

  12. Miopatias associadas a agregados tubulares

    Directory of Open Access Journals (Sweden)

    Mary Souza Carvalho

    1993-09-01

    Full Text Available Os autores relatam a caso de paciente de 58 anos de idade do sexo masculino, com quadro de características miastênicas tanto clínica como eletromiograficamente, no qual a biópsia muscular com histoquímica e microscopia eletrônica permitiu fazer o diagnostico de miopatia associada a agregados tubulares. É chamada a atenção para o fato de que as alterações anátomo-patológicas encontradas podem estar presentes em um grupo heterogêneo de pacientes com grande variedade de sintomas, não havendo portanto motivo para considerar-se a existência de uma miopatia com agregados tubulares, já que os achados anátomo-patológicos são inespecíficos e não configuram moléstia específica.

  13. Performance evaluation of a hybrid system for efficient palm oil mill effluent treatment via an air-cathode, tubular upflow microbial fuel cell coupled with a granular activated carbon adsorption.

    Science.gov (United States)

    Tee, Pei-Fang; Abdullah, Mohammad Omar; Tan, Ivy Ai Wei; Mohamed Amin, Mohamed Afizal; Nolasco-Hipolito, Cirilo; Bujang, Kopli

    2016-09-01

    An air-cathode MFC-adsorption hybrid system, made from earthen pot was designed and tested for simultaneous wastewater treatment and energy recovery. Such design had demonstrated superior characteristics of low internal resistance (29.3Ω) and favor to low-cost, efficient wastewater treatment and power generation (55mW/m(3)) with average current of 2.13±0.4mA. The performance between MFC-adsorption hybrid system was compared to the standalone adsorption system and results had demonstrated great pollutants removals of the integrated system especially for chemical oxygen demand (COD), biochemical oxygen demand (BOD3), total organic carbon (TOC), total volatile solids (TVS), ammoniacal nitrogen (NH3-N) and total nitrogen (TN) because such system combines the advantages of each individual unit. Besides the typical biological and electrochemical processes that happened in an MFC system, an additional physicochemical process from the activated carbon took place simultaneously in the MFC-adsorption hybrid system which would further improved on the wastewater quality.

  14. Renal tubular acidosis type 4 in pregnancy.

    Science.gov (United States)

    Jakes, Adam Daniel; Baynes, Kevin; Nelson-Piercy, Catherine

    2016-03-17

    We describe the clinical course of renal tubular acidosis (RTA) type 4 in pregnancy, which has not been previously published. Renal tubular acidosis type 4 is a condition associated with increased urinary ammonia secondary to hypoaldosteronism or pseudohypoaldosteronism. Pregnancy may worsen the hyperkalaemia and acidosis of renal tubular acidosis type 4, possibly through an antialdosterone effect. We advise regular monitoring of potassium and pH throughout pregnancy to ensure safe levels are maintained. 2016 BMJ Publishing Group Ltd.

  15. Miopatias associadas a agregados tubulares

    OpenAIRE

    Mary Souza Carvalho; Lusvarghi,Edgard S.; Ângela Lobo F. Levy; Paulo N. Borsoi Salum; Consuelo J. Rodrigues; José Antonio Levy

    1993-01-01

    Os autores relatam a caso de paciente de 58 anos de idade do sexo masculino, com quadro de características miastênicas tanto clínica como eletromiograficamente, no qual a biópsia muscular com histoquímica e microscopia eletrônica permitiu fazer o diagnostico de miopatia associada a agregados tubulares. É chamada a atenção para o fato de que as alterações anátomo-patológicas encontradas podem estar presentes em um grupo heterogêneo de pacientes com grande variedade de sintomas, não havendo por...

  16. Elastomer liners for geothermal tubulars Y267 EPDM Liner Program:

    Energy Technology Data Exchange (ETDEWEB)

    Hirasuna, A.R.; Davis, D.L.; Flickinger, J.E.; Stephens, C.A.

    1987-12-01

    The elastomer, Y267 EPDM, has been identified as a hydrothermally stable material which can operate at temperatures in excess of 320/sup 0/C. The goal of the Y267 Liner Program was to demonstrate the feasibility of using this material as a liner for mild steel tubulars to prevent or mitigate corrosion. If successful, the usage of EPDM lined pipe by the geothermal community may have a significant impact on operating costs and serve as a viable alternative to the use of alloyed tubulars. Tooling procedures were developed under this program to mold a 0.64 cm (0.25'') thick Y267 EPDM liner into a tubular test section 61 cm (2') in length and 19.1 cm (7.5'') in diameter (ID). A successful effort was made to identify a potential coupling agent to be used to bond the elastomer to the steel tubular wall. This agent was found to withstand the processing conditions associated with curing the elastomer at 288/sup 0/C and to retain a significant level of adhesive strength following hydrothermal testing in a synthetic brine at 260/sup 0/C for a period of 166 hours. Bonding tests were conducted on specimens of mild carbon steel and several alloys including Hastelloy C-276. An objective of the program was to field test the lined section of pipe mentioned above at a geothermal facility in the Imperial Valley. Though a test was conducted, problems encountered during the lining operation precluded an encouraging outcome. The results of the field demonstration were inconclusive. 6 refs., 13 figs., 13 tabs

  17. Genetic analyses of agronomic and seed quality traits of synthetic oilseed Brassica napus produced from interspecific hybridization of B. campestris and B. oleracea

    Indian Academy of Sciences (India)

    Guoqing Zhang; Weijun Zhou

    2006-04-01

    The heritability, the number of segregating genes and the type of gene interaction of nine agronomic traits were analysed based on F2 populations of synthetic oilseed Brassica napus produced from interspecific hybridization of B. campestris and B. oleracea through ovary culture. The nine traits—plant height, stem width, number of branches, length of main raceme, number of pods per plant, number of seeds per pod, length of pod, seed weight per plant and 1000-seed weight—had heritabilities of 0.927, 0.215, 0.172, 0.381, 0.360, 0.972, 0.952, 0.516 and 0.987 respectively, while the mean numbers of controlling genes for these characters were 7.4, 10.4, 9.9, 12.9, 11.5, 21.7, 20.5, 19.8 and 6.4 respectively. According to estimated coefficients of skewness and kurtosis of the traits tested, no significant gene interaction was found for plant height, stem width, number of branches, length of main raceme, number of seeds per pod and 1000-seed weight. Seed yield per plant is an important target for oilseed production. In partial correlation analysis, number of pods per plant, number of seeds per pod and 1000-seed weight were positively correlated with seed yield per plant. On the other hand, length of pod was negatively correlated ($r = -0.69$) with seed yield per plant. Other agronomic characters had no significant correlation to seed yield per plant. In this experiment, the linear regressions of seed yield per plant and other agronomic traits were also analysed. The linear regression equation was $y = 0.074x_{8} + 1.819x_{9} + 6.72x_{12} - 60.78 (R^{2} = 0.993)$, where $x_{8}$, $x_{9}$ and $x_{12}$ represent number of pods per plant, number of seeds per pod and 1000-seed weight respectively. The experiment also showed that erucic acid and oil contents of seeds from F2 plants were lower than those of their maternal parents. However, glucosinolate content was higher than that of the maternal plants. As for protein content, similar results were found in the F2 plants and

  18. Modified tubularized incised plate urethroplasty

    Directory of Open Access Journals (Sweden)

    Shivaji Mane

    2013-01-01

    Full Text Available Aim: To share our experience of doing tubularized incised plate urethroplasty with modifications. Materials and Methods: This is a single surgeon personal series from 2004 to 2009. One hundred patients of distal hypospadias were subjected for Snodgrass urethroplasty with preputioplasty. The age range was 1 to 5 year with mean age of 2.7 years. Selection criteria were good urethral plate, without chordee and torsion needing complete degloving. Main technical modification from original Snodgrass procedure was spongioplasty, preputioplasty, and dorsal slit when inability to retract prepuce during surgery. Results: Average follow-up period is 23 months. Seven (7% patients developed fistula and one patient had complete preputial dehiscence. Phimosis developed in three (3% patients and required circumcision. Dorsal slit was required in seven patients. One patient developed meatal stenosis in postoperative period. All other patients are passing single urinary stream and have cosmesis that is acceptable. Conclusions: Modified tubularized incised plate urethroplasty with preputioplasty effectively gives cosmetically normal looking penis with low complications.

  19. Cadmium and cisplatin damage erythropoietin-producing proximal renal tubular cells

    Energy Technology Data Exchange (ETDEWEB)

    Horiguchi, Hyogo; Oguma, Etsuko; Kayama, Fujio [Jichi Medical School, Division of Environmental Medicine, Center for Community Medicine, Tochigi (Japan); Core Research for Evolutional Science and Technology, Japan Science Technology Corporation (CREST-JST), Saitama (Japan)

    2006-10-15

    The concomitant manifestations of proximal renal tubular dysfunction and anemia with erythropoietin (Epo) deficiency observed in chronic cadmium (Cd) intoxication, such as Itai-itai disease, suggest a close local correlation between the Cd-targeted tubular cells and Epo-producing cells in the kidney. Therefore, we investigated the local relationship between hypoxia-induced Epo production and renal tubular injury in rats injected with Cd at 2 mg/kg twice a week for 8 months. Anemia due to insufficient production of Epo was observed in Cd-intoxicated rats. In situ hybridization detected Epo mRNA expression in the proximal renal tubular cells of hypoxic rats without Cd intoxication, and the Cd-intoxicated rats showed atrophy of Epo-expressing renal tubules and replacement of them with fibrotic tissue. A single dose of cisplatin at 8 mg/kg, which can induce clinical manifestations similar to those of Cd including renal tubular damage along with Epo-deficient anemia, resulted in Epo-expressing renal tubule destruction on day 4. These data indicate that Cd and cisplatin would induce anemia through the direct injury of the proximal renal tubular cells that are responsible for Epo production. (orig.)

  20. Tubular stabilizer bars – calculations and construction

    Directory of Open Access Journals (Sweden)

    Adam-Markus WITTEK

    2011-01-01

    Full Text Available The article outlines the calculation methods for tubular stabilizer bars. Modern technological and structural solutions in contemporary cars are reflected also in the construction, selection and manufacturing of tubular stabilizer bars. A proper construction and the selection of parameters influence the strength properties, the weight, durability and reliability as well as the selection of an appropriate production method.

  1. Tubular inverse opal scaffolds for biomimetic vessels

    Science.gov (United States)

    Zhao, Ze; Wang, Jie; Lu, Jie; Yu, Yunru; Fu, Fanfan; Wang, Huan; Liu, Yuxiao; Zhao, Yuanjin; Gu, Zhongze

    2016-07-01

    There is a clinical need for tissue-engineered blood vessels that can be used to replace or bypass damaged arteries. The success of such grafts depends strongly on their ability to mimic native arteries; however, currently available artificial vessels are restricted by their complex processing, controversial integrity, or uncontrollable cell location and orientation. Here, we present new tubular scaffolds with specific surface microstructures for structural vessel mimicry. The tubular scaffolds are fabricated by rotationally expanding three-dimensional tubular inverse opals that are replicated from colloidal crystal templates in capillaries. Because of the ordered porous structure of the inverse opals, the expanded tubular scaffolds are imparted with circumferentially oriented elliptical pattern microstructures on their surfaces. It is demonstrated that these tailored tubular scaffolds can effectively make endothelial cells to form an integrated hollow tubular structure on their inner surface and induce smooth muscle cells to form a circumferential orientation on their outer surface. These features of our tubular scaffolds make them highly promising for the construction of biomimetic blood vessels.There is a clinical need for tissue-engineered blood vessels that can be used to replace or bypass damaged arteries. The success of such grafts depends strongly on their ability to mimic native arteries; however, currently available artificial vessels are restricted by their complex processing, controversial integrity, or uncontrollable cell location and orientation. Here, we present new tubular scaffolds with specific surface microstructures for structural vessel mimicry. The tubular scaffolds are fabricated by rotationally expanding three-dimensional tubular inverse opals that are replicated from colloidal crystal templates in capillaries. Because of the ordered porous structure of the inverse opals, the expanded tubular scaffolds are imparted with circumferentially

  2. Tubular bioreactor and its application; Tubular bioreactor to sono tekiyo

    Energy Technology Data Exchange (ETDEWEB)

    Endo, I.; Nagamune, T. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering; Yuki, K. [Nikka Whisky Distilling Co. Ltd. Tokyo (Japan); Inaba, H. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

    1994-09-05

    The loop type tubular bioreactor (TBR) was developed where biocatalysts are trapped in the reactor by membrane module. A UF membrane or MF membrane and crossflow filtration were adopted for the membrane module, and the reactor loop was composed of four membrane modules. The reactor was operated at 2-4 m/s in membrane surface velocity and 300-400 kPa in filtration pressure. As the result of the high-density culture of lactic acid bacteria and yeast, a biomass concentration was more than 10 times that in batch culture, suggesting the remarkable enhancement of a production efficiency. As the result of the continuous fermentation of cider, the fast fermentation more than 60 times that in conventional ones was obtained together with the same quality as conventional ones. Such a fast fermentation was probably achieved by yeast suspended in the fermenter of TBR, by yeast hardly affected physico-chemically as compared with immobilized reactors, and by small effect of mass transfer on reaction systems. 4 refs., 6 figs.

  3. Inverse Approach to Evaluate the Tubular Material Parameters Using the Bulging Test

    Directory of Open Access Journals (Sweden)

    Yulong Ge

    2015-01-01

    Full Text Available Tubular material parameters are required for both part manufactory process planning and finite element simulations. The bulging test is one of the most credible ways to detect the property parameters for tubular material. The inverse approach provides more effective access to the accurate material evaluation than with direct identifications. In this paper, a newly designed set of bulging test tools is introduced. An inverse procedure is adopted to determine the tubular material properties in Krupkowski-Swift constitutive model of material deformation using a hybrid algorithm that combines the differential evolution and Levenberg-Marquardt algorithms. The constitutive model’s parameters obtained from the conventional and inverse methods are compared, and this comparison shows that the inverse approach is able to offer more information with higher reliability and can simplify the test equipment.

  4. Proximal tubular hypertrophy and enlarged glomerular and proximal tubular urinary space in obese subjects with proteinuria.

    Directory of Open Access Journals (Sweden)

    Ana Tobar

    Full Text Available BACKGROUND: Obesity is associated with glomerular hyperfiltration, increased proximal tubular sodium reabsorption, glomerular enlargement and renal hypertrophy. A single experimental study reported an increased glomerular urinary space in obese dogs. Whether proximal tubular volume is increased in obese subjects and whether their glomerular and tubular urinary spaces are enlarged is unknown. OBJECTIVE: To determine whether proximal tubules and glomerular and tubular urinary space are enlarged in obese subjects with proteinuria and glomerular hyperfiltration. METHODS: Kidney biopsies from 11 non-diabetic obese with proteinuria and 14 non-diabetic lean patients with a creatinine clearance above 50 ml/min and with mild or no interstitial fibrosis were retrospectively analyzed using morphometric methods. The cross-sectional area of the proximal tubular epithelium and lumen, the volume of the glomerular tuft and of Bowman's space and the nuclei number per tubular profile were estimated. RESULTS: Creatinine clearance was higher in the obese than in the lean group (P=0.03. Proteinuria was similarly increased in both groups. Compared to the lean group, the obese group displayed a 104% higher glomerular tuft volume (P=0.001, a 94% higher Bowman's space volume (P=0.003, a 33% higher cross-sectional area of the proximal tubular epithelium (P=0.02 and a 54% higher cross-sectional area of the proximal tubular lumen (P=0.01. The nuclei number per proximal tubular profile was similar in both groups, suggesting that the increase in tubular volume is due to hypertrophy and not to hyperplasia. CONCLUSIONS: Obesity-related glomerular hyperfiltration is associated with proximal tubular epithelial hypertrophy and increased glomerular and tubular urinary space volume in subjects with proteinuria. The expanded glomerular and urinary space is probably a direct consequence of glomerular hyperfiltration. These effects may be involved in the pathogenesis of obesity

  5. Genetics Home Reference: tubular aggregate myopathy

    Science.gov (United States)

    ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Share: Email Facebook Twitter Home Health Conditions tubular ... my family? What is the prognosis of a genetic condition? Genetic and Rare Diseases Information Center Frequency ...

  6. Iatrogenic Digital Compromise with Tubular Dressings

    Directory of Open Access Journals (Sweden)

    Corre, Kenneth A

    2009-08-01

    Full Text Available Objective: This case report describes a digit amputation resulting from an improperly applied tubular dressing. The safe application of digital tubular dressings, and the rationale behind it, is detailed to raise emergency physician (EP awareness.Methods: We present a case report of a recent iatrogenic-induced digit ischemia caused by improperly applied tube gauze. We review the literature on the subject and the likely sources of poor outcomes presented. The proper application of tubular gauze dressings is then outlined.Conclusion: EPs and emergency department personnel must be educated on the safe application of tubular gauze dressings to avoid dire outcomes associated with improper applications.[WestJEM. 2009;10:190-192.

  7. Genetics Home Reference: renal tubular dysgenesis

    Science.gov (United States)

    ... groups? Genetic Changes Mutations in the ACE , AGT , AGTR1 , or REN gene can cause renal tubular dysgenesis . ... receptor type 1 (AT1 receptor; produced from the AGTR1 gene), stimulating chemical signaling. By binding to the ...

  8. 78 FR 37584 - U.S. Steel Tubular Products, Inc., Mckeesport Tubular Operations Division, Subsidiary of United...

    Science.gov (United States)

    2013-06-21

    ... Employment and Training Administration U.S. Steel Tubular Products, Inc., Mckeesport Tubular Operations Division, Subsidiary of United States Steel Corporation, Mckeesport, Pennsylvania; Notice of Amended... workers of U.S. Steel Tubular Products, McKeesport Tubular Operations Division, a subsidiary of...

  9. Semi-synthesis of biologically active nisin hybrids composed of the native lanthionine ABC-fragment and a cross-stapled synthetic DE-fragment

    NARCIS (Netherlands)

    Slootweg, Jack C.; Peters, Nienke; Quarles Van Ufford, H. C.; Breukink, Eefjan; Liskamp, Rob M J; Rijkers, Dirk T S

    2014-01-01

    The antimicrobial peptide nisin is a promising template for designing novel peptide-based antibiotics to improve its drug-like properties. First steps in that direction represent the synthesis of hybrid nisin derivatives that contain a native nisin ABC-part and synthesized cross-stapled DE-ring frag

  10. Tubular Structures Self-Assembled from a Bola-Amphiphilic Pillar[5]arene in Water and Applied as a Microreactor.

    Science.gov (United States)

    Chen, Rener; Jiang, Huajiang; Gu, Haining; Zhou, Qizhong; Zhang, Zhen; Wu, Jiashou; Jin, Zhengneng

    2015-09-04

    Various nanomorphologies were obtained by simply changing the fabrication conditions, such as the pH of the system, different solvent, or different concentration, of bola-amphiphilic pillar[5]arene Bola-AP5. Importantly, hybrid microtubules as a microreactor were successfully prepared by directly reducing AuCl4(-) on the surface of Bola-AP5-based tubular structures in water.

  11. Comparative Reproductive and Growth Performance of Clarias gariepinus (Burchell, 1822) and Its Hybrid Induced with Synthetic Hormone and Pituitary Gland of Clarias gariepinus

    OpenAIRE

    Ndimele, Prince Emeka; Owodeinde, Fatai Gbolahan

    2012-01-01

    A study was conducted to determine the comparative reproductive, growth performances and nutrient utilization of Clarias gariepinus and its hybrid "heteroclarias" using ovaprim and pituitary extract of male and female C. gariepinus. The experimental broodstocks consisted of 6 female C. gariepinus (2 each were induced separately with ovaprim, male pituitary of C. gariepinus and female pituitary of C. gariepinus), 3 male C. gariepinus and 3 male Heterobranchus bidorsalis. 2 female C. ...

  12. Improvement of barrier properties of a hybrid sol-gel coating by incorporation of synthetic talc-like phyllosilicates for corrosion protection of a carbon steel

    OpenAIRE

    2012-01-01

    International audience; Sol-gel coatings for corrosion protection of metals are a good alternative to toxic chromate treatments. The present work focussed on the incorporation of inorganic fillers in a sol-gel coating to improve the barrier properties of the film. Talc-like phyllosilicates obtained by hydrothermal synthesis at 160°C, 260°C and 350°C, called T160, T260 and T350 respectively, were selected as inorganic fillers. The synthetic materials showed talc lamellar structure but, in cont...

  13. Tubular Colonic Duplication Presenting as Rectovestibular Fistula.

    Science.gov (United States)

    Karkera, Parag J; Bendre, Pradnya; D'souza, Flavia; Ramchandra, Mukunda; Nage, Amol; Palse, Nitin

    2015-09-01

    Complete colonic duplication is a very rare congenital anomaly that may have different presentations according to its location and size. Complete colonic duplication can occur in about 15% of all gastrointestinal duplications. Double termination of tubular colonic duplication in the perineum is even more uncommon. We present a case of a Y-shaped tubular colonic duplication which presented with a rectovestibular fistula and a normal anus. Radiological evaluation and initial exploration for sigmoidostomy revealed duplicated colons with a common vascular supply. Endorectal mucosal resection of theduplicated distal segment till the colostomy site with division of the septum of the proximal segment and colostomy closure proved curative without compromise of the continence mechanism. Tubular colonic duplication should always be ruled out when a diagnosis of perineal canal is considered in cases of vestibular fistula alongwith a normal anus.

  14. Deployable and retractable telescoping tubular structure development

    Science.gov (United States)

    Thomson, M. W.

    1994-01-01

    A new deployable and retractable telescoping boom capable of high deployed stiffness and strength is described. Deployment and retraction functions are controlled by simple, reliable, and fail-safe latches between the tubular segments. The latch and a BI-STEM (Storable Tubular Extendible Member) actuator work together to eliminate the need for the segments to overlap when deployed. This yields an unusually lightweight boom and compact launch configuration. An aluminum space-flight prototype with three joints displays zero structural deadband, low hysteresis, and high damping. The development approach and difficulties are discussed. Test results provide a joint model for sizing flight booms of any diameter and length.

  15. Tubular membrane bioreactors for biotechnological processes.

    Science.gov (United States)

    Wolff, Christoph; Beutel, Sascha; Scheper, Thomas

    2013-02-01

    This article is an overview of bioreactors using tubular membranes such as hollow fibers or ceramic capillaries for cultivation processes. This diverse group of bioreactor is described here in regard to the membrane materials used, operational modes, and configurations. The typical advantages of this kind of system such as environments with low shear stress together with high cell densities and also disadvantages like poor oxygen supply are summed up. As the usage of tubular membrane bioreactors is not restricted to a certain organism, a brief overview of various applications covering nearly all types of cells from prokaryotic to eukaryotic cells is also given here.

  16. Synthetic environments

    Science.gov (United States)

    Lukes, George E.; Cain, Joel M.

    1996-02-01

    The Advanced Distributed Simulation (ADS) Synthetic Environments Program seeks to create robust virtual worlds from operational terrain and environmental data sources of sufficient fidelity and currency to interact with the real world. While some applications can be met by direct exploitation of standard digital terrain data, more demanding applications -- particularly those support operations 'close to the ground' -- are well-served by emerging capabilities for 'value-adding' by the user working with controlled imagery. For users to rigorously refine and exploit controlled imagery within functionally different workstations they must have a shared framework to allow interoperability within and between these environments in terms of passing image and object coordinates and other information using a variety of validated sensor models. The Synthetic Environments Program is now being expanded to address rapid construction of virtual worlds with research initiatives in digital mapping, softcopy workstations, and cartographic image understanding. The Synthetic Environments Program is also participating in a joint initiative for a sensor model applications programer's interface (API) to ensure that a common controlled imagery exploitation framework is available to all researchers, developers and users. This presentation provides an introduction to ADS and the associated requirements for synthetic environments to support synthetic theaters of war. It provides a technical rationale for exploring applications of image understanding technology to automated cartography in support of ADS and related programs benefitting from automated analysis of mapping, earth resources and reconnaissance imagery. And it provides an overview and status of the joint initiative for a sensor model API.

  17. Synthetic foldamers.

    Science.gov (United States)

    Guichard, Gilles; Huc, Ivan

    2011-06-07

    Foldamers are artificial folded molecular architectures inspired by the structures and functions of biopolymers. This highlight focuses on important developments concerning foldamers produced by chemical synthesis and on the perspectives that these new self-organized molecular scaffolds offer. Progress in the field has led to synthetic objects that resemble small proteins in terms of size and complexity yet that may not contain any α-amino acids. Foldamers have introduced new tools and concepts to develop biologically active substances, synthetic receptors and novel materials.

  18. Parametric sensitivity and runaway in tubular reactors

    Energy Technology Data Exchange (ETDEWEB)

    Morbidelli, M.; Varma, A.

    1982-09-01

    Parametric sensitivity of tubular reactors is analyzed to provide critical values of the heat of reaction and heat transfer parameters defining runaway and stable operations for all positive-order exothermic reactions with finite activation energies, and for all reactor inlet temperatures. Evaluation of the critical values does not involve any trial and error.

  19. Startup of an industrial adiabatic tubular reactor

    NARCIS (Netherlands)

    Verwijs, J.W.; Berg, van den H.; Westerterp, K.R.

    1992-01-01

    The dynamic behaviour of an adiabatic tubular plant reactor during the startup is demonstrated, together with the impact of a feed-pump failure of one of the reactants. A dynamic model of the reactor system is presented, and the system response is calculated as a function of experimentally-determine

  20. Centrifugal Casting of Tubular Perovskite Membranes

    NARCIS (Netherlands)

    Mertins, Frederic H.B.; Kruidhof, Henk; Bouwmeester, Henny J.M.

    2005-01-01

    Dense tubular membranes were produced by centrifugal casting of an aqueous suspension, containing powder particles of the mixed-conducting perovskite La0.5Sr0.5CoO3−δ and a dispersant. The resulting green bodies were dried and sintered to produce tubes with a maximum length of 12 cm, having a relat

  1. Tubular Membrane Plant-Growth Unit

    Science.gov (United States)

    Dreschel, Thomas W.

    1992-01-01

    Hydroponic system controls nutrient solution for growing crops in space. Pump draws nutrient solution along inside of tubular membrane in pipe from reservoir, maintaining negative pressure in pipe. Roots of plants in slot extract nutrient through membrane within pipe. Crop plants such as wheat, rice, lettuce, tomatoes, soybeans, and beans grown successfully with system.

  2. Drill pipes and casings utilizing multi-conduit tubulars

    Energy Technology Data Exchange (ETDEWEB)

    Curlett, H.B.

    1989-01-24

    A seal adapted for use with a multi-conduit well tubular, or the like, is described which consists of: a plate with fluid passages, each passage corresponding to an opening of a conduit of the multiconduit tubular, and a groove on the plate around each passage; and elastomer means partially embeddable into each groove for sealing each conduit of a tubular to a corresponding conduit of another similar tubular.

  3. Development of Partial Tubular Flat Knitting Fabric Composite Preform

    Directory of Open Access Journals (Sweden)

    Jiang Wei Qing

    2016-01-01

    Full Text Available After building some structures of partial tubular flat knitting fabric composite preform, the influencing factor on tubular section was analyzed and the fabric was knitted selectively. The partial tubular flat knitting fabric composite preform were Knitted by changing different yarn, row number and two-sided partial tubular flat knitting fabric. Multilayer sheet would be got after hot pressing and it has big market prospects and good application value.

  4. Reliability Analysis of Tubular Joints in Offshore Structures

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Sørensen, John Dalsgaard

    1987-01-01

    Reliability analysis of single tubular joints and offshore platforms with tubular joints is" presented. The failure modes considered are yielding, punching, buckling and fatigue failure. Element reliability as well as systems reliability approaches are used and illustrated by several examples....... Finally, optimal design of tubular.joints with reliability constraints is discussed and illustrated by an example....

  5. Twisted tubular photobioreactor fluid dynamics evaluation for energy consumption minimization

    NARCIS (Netherlands)

    Gómez-Pérez, C.A.; Espinosa Oviedo, J.J.; Montenegro Ruiz, L.C.; Boxtel, van A.J.B.

    2017-01-01

    This paper discusses a new tubular PhotoBioReactor (PBR) called twisted tubular PBR. The geometry of a twisted tubular PBR induces swirl mixing to guarantee good exposure of microalgae to Light-Dark (LD) cycles and to the nutrients and dissolved CO 2 . The paper analyses the energy uptake for fluid

  6. Synthetic Astrobiology

    Science.gov (United States)

    Rothschild, Lynn J.

    2016-01-01

    Synthetic biology - the design and construction of new biological parts and systems and the redesign of existing ones for useful purposes - has the potential to transform fields from pharmaceuticals to fuels. Our lab has focused on the potential of synthetic biology to revolutionize all three major parts of astrobiology: Where do we come from? Where are we going? and Are we alone? For the first and third, synthetic biology is allowing us to answer whether the evolutionary narrative that has played out on planet earth is likely to have been unique or universal. For example, in our lab we are re-evolving the biosynthetic pathways of amino acids in order to understand potential capabilities of an early organism with a limited repertoire of amino acids and developing techniques for the recovery of metals from spent electronics on other planetary bodies. And what about the limits for life? Can we create organisms that expand the envelope for life? In the future synthetic biology will play an increasing role in human activities both on earth, in fields as diverse as human health and the industrial production of novel bio-composites. Beyond earth, we will rely increasingly on biologically-provided life support, as we have throughout our evolutionary history. In order to do this, the field will build on two of the great contributions of astrobiology: studies of the origin of life and life in extreme environments.

  7. Synthetic Astrobiology

    Science.gov (United States)

    Rothschild, Lynn J.

    2015-01-01

    Synthetic biology - the design and construction of new biological parts and systems and the redesign of existing ones for useful purposes - has the potential to transform fields from pharmaceuticals to fuels. Our lab has focused on the potential of synthetic biology to revolutionize all three major parts of astrobiology: Where do we come from? Where are we going? and Are we alone? For the first and third, synthetic biology is allowing us to answer whether the evolutionary narrative that has played out on planet earth is likely to have been unique or universal. For example, in our lab we are re-evolving the biosynthetic pathways of amino acids in order to understand potential capabilities of an early organism with a limited repertoire of amino acids and developing techniques for the recovery of metals from spent electronics on other planetary bodies. In the future synthetic biology will play an increasing role in human activities both on earth, in fields as diverse as human health and the industrial production of novel bio-composites. Beyond earth, we will rely increasingly on biologically-provided life support, as we have throughout our evolutionary history. In order to do this, the field will build on two of the great contributions of astrobiology: studies of the origin of life and life in extreme environments.

  8. STUDY THE CREEP OF TUBULAR SHAPED FIBER REINFORCED COMPOSITES

    Directory of Open Access Journals (Sweden)

    Najat J. Saleh

    2013-05-01

    Full Text Available Inpresent work tubular –shaped fiber reinforced composites were manufactured byusing two types of resins ( Epoxy and unsaturated polyester and separatelyreinforced with glass, carbon and kevlar-49 fibers (filament and woven roving,hybrid reinforcement composites of these fibers were also prepared. The fiberswere wet wound on a mandrel using a purposely designed winding machine,developed by modifying an ordinary lathe, in winding angle of 55° for filament. A creep test was made of either the fulltube or specimens taken from it. Creep was found to increase upon reinforcementin accordance to the rule of mixture and mainly decided by the type of singleor hybridized fibers. The creep behavior, showed that the observed strain tendsto appear much faster at higher temperature as compared with that exhibited atroom temperate. The creep rate also found to be depending on fiber type, matrixtype, and the fiber /matrix bonding. The creep energy calculated fromexperimental observations was found to exhibit highest value for hybridizedreinforcement.

  9. Sensibilidad in vitro de micobacterias a dos péptidos sintéticos híbridos con actividad antimicrobiana In-vitro activity of two hybrid synthetic peptides having antimicrobial activity against mycobacteria

    Directory of Open Access Journals (Sweden)

    E. Zerbini

    2006-12-01

    Full Text Available El aumento de aislamientos clínicos de Mycobacterium tuberculosis resistentes a las drogas esenciales y de casos de micobacteriosis diseminadas debidas al complejo Mycobacterium avium hacen necesario investigar nuevos agentes antimicobacterianos. Los péptidos antimicrobianos son un nuevo grupo de antibióticos que poseen un mecanismo de acción particular. Algunos de ellos, como la cecropina y la melitina, han sido aislados de insectos y han demostrado buena actividad in vitro contra bacterias gram positivas y gram negativas. Híbridos sintéticos de esos péptidos han presentado mayor actividad que los péptidos individuales. En este trabajo se evaluó la actividad in vitro de dos péptidos híbridos sintéticos de melitina y cecropina contra M. tuberculosis, complejo M. avium, Mycobacterium fortuitum y Mycobacterium smegmatis. Se determinó la concentración inhibitoria mínima empleando la técnica de macrodilución en caldo. Luego se estableció la concentración bactericida mínima en medio Lowenstein Jensen. Los péptidos evaluados mostraron ser activos in vitro contra M. smegmatis, mientras que no presentaron ninguna actividad contra las otras micobacterias estudiadas.The increase in both Mycobacterium tuberculosis human clinical isolates resistant to the essential drugs and cases of disseminated micobacteriosis due to Mycobacterium avium Complex, underlines the need to investigate new antimicobacterial agents. The antimicrobial peptides are a new group of active antibiotics with a particular mechanism of action. Some of them, like cecropin and melittin, isolated from insects, have demonstrated good in vitro activity against Gram-positive and Gram-negative bacteria. Synthetic hybrids of those peptides have been more active than individual peptides. In this study, the in vitro activity of two hybrid synthetic peptides from melittin and cecropin against M. tuberculosis, M. avium Complex, Mycobacterium fortuitum and Mycobacterium smegmatis

  10. 掺入混杂合成纤维的混凝土力学性能分析%Analysis of Mechanical Properties of Concrete Mixed with Hybrid Synthetic Fiber

    Institute of Scientific and Technical Information of China (English)

    胡建荣; 何锐; 李永鹏

    2015-01-01

    采用高弹模聚乙烯纤维(PE)和低弹模聚丙烯粗合成纤维(CPP)混杂技术制备混杂纤维混凝土,对其抗压和抗弯性能进行测试,并采用双因素方差分析法对弯曲韧性影响因素的显著性特征进行了分析,同时还对混杂纤维的增强增韧机理进行了探讨.结果表明 :在不同的粗集料掺量下,混杂纤维混凝土抗压强度普遍高于素混凝土,其提高幅度主要集中在15%~30% 之间;掺入混杂纤维后混凝土试件的荷载-挠度曲线整体较为饱满,多数曲线表现为变形缓慢软化,部分出现变形硬化特征;纤维掺量对混凝土的韧性有非常显著的影响,而粗集料掺量影响较小;CPP/PE纤维可以从不同层次结构对混凝土进行增韧,产生正混杂效应 ,从而使制备的混杂纤维混凝土具有优异的韧性.%The hybrid fiber-reinforced concrete was prepared by using the polyethylene fiber ( PE) of a high elastic modulus and the polypropylene synthetic fibers ( CPP) of a low elastic modulus , and its flexural behaviors and com-pressive resistance were determined .Then, the significances of the factors influencing the flexural toughness were discussed through a two-factor variance analysis , and the toughening mechanism of the hybrid fiber was explored . The results show that ( 1 ) the compressive strength of hybrid fiber-reinforced concrete specimens with different coarse aggregate contents is generally higher than that of plain concrete , and the improvement ranges are mainly be-tween 15%~30%; ( 2 ) the load-deflection curves of the concrete specimens with the hybrid fiber are relatively full;and, furthermore, most curves exhibit a slow deformation softening characteristic while some display a defor-mation hardening characteristic; ( 3 ) the fiber content has a significant effect on the toughness of the concrete , while the coarse aggregate dosage has a smaller one;and (4) the CPP/PE fiber can toughen the concrete from dif-ferent hierarchies

  11. 78 FR 14361 - U.S. Steel Tubular Products, Inc., Mckeesport Tubular Operations Division, Subsidiary of United...

    Science.gov (United States)

    2013-03-05

    ... Employment and Training Administration U.S. Steel Tubular Products, Inc., Mckeesport Tubular Operations Division, Subsidiary of United States Steel Corporation, Mckeesport, PA; Notice of Initiation of...) filed on December 20, 2012 on behalf of workers of U.S. Steel Tubular Products, McKeesport...

  12. Distal renal tubular acidosis in recurrent renal stone formers

    DEFF Research Database (Denmark)

    Osther, P J; Hansen, A B; Røhl, H F

    1989-01-01

    (1.1%) had complete distal renal tubular acidosis and 14 (15.5%) incomplete distal renal tubular acidosis. Our results confirm that distal renal tubular acidification defects are associated with a more severe form of stone disease and make distal renal tubular acidosis one of the most frequent...... metabolic disturbances in renal stone formers. Distal renal tubular acidosis (dRTA) was relatively more common in female stone formers and most often found in patients with bilateral stone disease (36%). Since prophylactic treatment in renal stone formers with renal acidification defects is available...

  13. Multi-Scaled Modeling the Mechanical Properties of Tubular Composites Reinforced with Innovated 3D Weft Knitted Spacer Fabrics

    Science.gov (United States)

    Omrani, Elahe; Hasani, Hossein; Dibajian, Sayed Houssain

    2017-06-01

    Textile composites of 3D integrated spacer configurations have been recently focused by several researchers all over the world. In the present study, newly-designed tubular composites reinforced with 3D spacer weft knitted fabrics were considered and the effects of their structural parameters on some applicable mechanical properties were investigated. For this purpose, two different samples of 3D spacer weft knitted textile types in tubular form were produced on an electronic flat knitting machine, using glass/nylon hybrid yarns. Thermoset tubular-shaped composite parts were manufactured via vacuum infusion molding process using epoxy resin. The mechanical properties of the produced knitted composites in term of external static and internal hydrostatic pressures were evaluated. Resistance of the produced composites against the external static and internal hydrostatic pressures was numerically simulated using multi-scale modeling method. The finding revealed that there is acceptable correlation between experimental and theoretical results.

  14. Research and application of a hybrid model based on dynamic fuzzy synthetic evaluation for establishing air quality forecasting and early warning system: A case study in China.

    Science.gov (United States)

    Xu, Yunzhen; Du, Pei; Wang, Jianzhou

    2017-04-01

    As the atmospheric environment pollution has been becoming more and more serious in China, it is highly desirable to develop a scientific and effective early warning system that plays a great significant role in analyzing and monitoring air quality. However, establishing a robust early warning system for warning the public in advance and ameliorating air quality is not only an extremely challenging task but also a public concerned problem for human health. Most previous studies are focused on improving the prediction accuracy, which usually ignore the significance of uncertainty information and comprehensive evaluation concerning air pollutants. Therefore, in this paper a novel robust early warning system was successfully developed, which consists of three modules: evaluation module, forecasting module and characteristics estimating module. In this system, a new dynamic fuzzy synthetic evaluation is proposed and applied to determine air quality levels and primary pollutants, which can be regarded as the research objectives; Moreover, to further mine and analyze the characteristics of air pollutants, four different distribution functions and interval forecasting method are also employed that can not only provide predictive range, confidence level and the other uncertain information of the pollutants future values, but also assist decision-makers in reducing and controlling the emissions of atmospheric pollutants. Case studies utilizing hourly PM2.5, PM10 and SO2 data collected from Tianjin and Shanghai in China are applied as illustrative examples to estimate the effectiveness and efficiency of the proposed system. Experimental results obviously indicated that the developed novel early warning system is much suitable for analyzing and monitoring air pollution, which can also add a novel viable option for decision-makers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Synthetic chromosomes.

    Science.gov (United States)

    Schindler, Daniel; Waldminghaus, Torsten

    2015-11-01

    What a living organism looks like and how it works and what are its components-all this is encoded on DNA, the genetic blueprint. Consequently, the way to change an organism is to change its genetic information. Since the first pieces of recombinant DNA have been used to transform cells in the 1970s, this approach has been enormously extended. Bigger and bigger parts of the genetic information have been exchanged or added over the years. Now we are at a point where the construction of entire chromosomes becomes a reachable goal and first examples appear. This development leads to fundamental new questions, for example, about what is possible and desirable to build or what construction rules one needs to follow when building synthetic chromosomes. Here we review the recent progress in the field, discuss current challenges and speculate on the appearance of future synthetic chromosomes.

  16. Optimization Study of Shaft Tubular Turbine in a Bidirectional Tidal Power Station

    Directory of Open Access Journals (Sweden)

    Xinfeng Ge

    2013-01-01

    Full Text Available The shaft tubular turbine is a form of tidal power station which can provide bidirectional power. Efficiency is an important turbine performance indicator. To study the influence of runner design parameters on efficiency, a complete 3D flow-channel model of a shaft tubular turbine was developed, which contains the turbine runner, guide vanes, and flow passage and was integrated with hybrid grids calculated by steady-state calculation methods. Three aspects of the core component (turbine runner were optimized by numerical simulation. All the results were then verified by experiments. It was shown that curved-edge blades are much better than straight-edge blades; the optimal blade twist angle is 7°, and the optimal distance between the runner and the blades is 0.75–1.25 times the diameter of the runner. Moreover, the numerical simulation results matched the experimental data very well, which also verified the correctness of the optimal results.

  17. Study of hydrodynamic characteristics in tubular photobioreactors.

    Science.gov (United States)

    Zhang, Qinghua; Wu, Xia; Xue, Shengzhang; Liang, Kehong; Cong, Wei

    2013-02-01

    In this work, the hydrodynamic characteristics in tubular photobioreactors with a series of helical static mixers built-in were numerically investigated using computational fluid dynamics (CFD). The influences of height and screw pitch of the helical static mixer and fluid inlet velocity on the cell trajectories, swirl numbers and energy consumption were examined. In order to verify the actual results for cultivation of microalgae, cultivation experiments of freshwater Chlorella sp. were carried out in photobioreactor with and without helical static mixer built-in at the same time. It was shown that with built-in helical static mixer, the mixing of fluid could be intensified, and the light/dark cycle could also be achieved which is of benefit for the growth of microalgae. The biomass productivity of Chlorella sp. in tubular photobioreactor with helical static mixer built-in was 37.26 % higher than that in the photobioreactor without helical static mixer.

  18. SOFC mini-tubulares basadas en YSZ

    Directory of Open Access Journals (Sweden)

    Campana, R.

    2008-08-01

    Full Text Available Tubular SOFC have the advantage over planar SOFC of the low temperature sealing and more resistance to thermal shock. On the other hand the volumetric power density of tubular Fuel Cells goes with the inverse of the tube diameter which added to the faster warm-up kinetics makes low diameter tubular SOFC favorable for low power applications. Anode supported tubular SOFC of 3mm diameter and 150 mm length with YSZ electrolyte were fabricated and tested by V-I measurements using H2-Ar (5, 10, 100 vol% as fuel and air for the cathode. The NiO-YSZ tubes of about 400 μm thickness were produced by hydrostatic pressure and then coated with an YSZ film of 15-20 μm. The electrolyte was deposited using a manual aerograph. After sintering either Pt paste or LSF (with YSZ or SDC coatings of about 20-50 μm thickness were deposited for the cathode. The OCV of the cells were excellent, very close to the expected Nernst law prediction indicating that there were not gas leaks. The maximun electrical power of the cell was near to 500mW/cm2 at 850ºC operation temperature. Complex impedance measurements of the cells were performed in order to determine the resistance of the different cell components.

    La principal ventaja de las SOFC tubulares frente a las planares es el sellado de la cámara anódica y catódica a bajas temperaturas. Además la densidad de energía volumétrica de las pilas tubulares es inversamente proporcional al diámetro del tubo, que añadido a los tiempos cortos de encendido y apagado hacen que las mini-tubulares sean interesantes para usos de baja potencia. Se han fabricado y caracterizado SOFC tubulares soportadas en ánodo de 3mm de diámetro y de 150 mm de longitud, 400μm de espesor, con electrolito de YSZ depositado por spray de 15-20 μm. Los tubos de NiO-YSZ son producidos por prensado isostático. La caracterización eléctrica se ha realizado empleando H2-Ar como combustible an

  19. A Tubular Aortopulmonary Window: An Embryological Curiosity.

    Science.gov (United States)

    Chidambarathanu, Shanthi; Agarwal, Ravi; Hussain, Zahra M; Brown, Nigel A; Anderson, Robert H

    2016-05-01

    We describe, in this report, an unusually shaped aortopulmonary communication observed in a six-month-old infant who presented with an associated ventricular septal defect. The defect was tubular, measuring 7 mm in length, and located intrapericardially between the proximal ascending aorta and the pulmonary trunk. It was well defined by transthoracic echocardiogram and was suitable for surgical ligation. We share our dilemma in naming this defect appropriately. We base our explanation on our understanding of normal development of the intrapericardial arterial trunks. There is initially an extensive aortopulmonary foramen. This is closed by apposition of a protrusion from the dorsal wall of the aortic sac, the aortopulmonary septum, with the distal margins of the outflow cushions. The spiral nature of formation of the aortopulmonary septum provides an understanding of the configuration of our tubular aortopulmonary window.

  20. Targeting apoptosis in acute tubular injury.

    Science.gov (United States)

    Ortiz, Alberto; Justo, Pilar; Sanz, Ana; Lorz, Corina; Egido, Jesús

    2003-10-15

    Recent research has shown that apoptosis and its regulatory mechanisms contribute to cell number regulation in acute renal failure. Acute tubular necrosis is the most frequent form of parenchymal acute renal failure. The main causes are ischemia-reperfusion, sepsis and nephrotoxic drugs. Exogenous factors such as nephrotoxic drugs and bacterial products, and endogenous factors such as lethal cytokines promote tubular cell apoptosis. Such diverse stimuli engage intracellular death pathways that in some cases are stimulus-specific. We now review the role of apoptosis in acute renal failure, the potential molecular targets of therapeutic intervention, the therapeutic weapons to modulate the activity of these targets and the few examples of therapeutic intervention on apoptosis.

  1. Pointlike Inclusion Interactions in Tubular Membranes

    Science.gov (United States)

    Vahid, Afshin; Idema, Timon

    2016-09-01

    Membrane tubes and tubular networks are ubiquitous in living cells. Inclusions like proteins are vital for both the stability and the dynamics of such networks. These inclusions interact via the curvature deformations they impose on the membrane. We analytically study the resulting membrane mediated interactions in strongly curved tubular membranes. We model inclusions as constraints coupled to the curvature tensor of the membrane tube. First, as special test cases, we analyze the interaction between ring- and rod-shaped inclusions. Using Monte Carlo simulations, we further show how pointlike inclusions interact to form linear aggregates. To minimize the curvature energy of the membrane, inclusions self-assemble into either line- or ringlike patterns. Our results show that the global curvature of the membrane strongly affects the interactions between proteins embedded in it, and can lead to the spontaneous formation of biologically relevant structures.

  2. Distal renal tubular acidosis with hereditary spherocytosis.

    Science.gov (United States)

    Sinha, Rajiv; Agarwal, Indira; Bawazir, Waleed M; Bruce, Lesley J

    2013-07-01

    Hereditary spherocytosis (HS) and distal renal tubular acidosis (dRTA), although distinct entities, share the same protein i.e. the anion exchanger1 (AE1) protein. Despite this, their coexistence has been rarely reported. We hereby describe the largest family to date with co-existence of dRTA and HS and discuss the molecular basis for the co-inheritance of these conditions.

  3. Mechanisms in hyperkalemic renal tubular acidosis.

    Science.gov (United States)

    Karet, Fiona E

    2009-02-01

    The form of renal tubular acidosis associated with hyperkalemia is usually attributable to real or apparent hypoaldosteronism. It is therefore a common feature in diabetes and a number of other conditions associated with underproduction of renin or aldosterone. In addition, the close relationship between potassium levels and ammonia production dictates that hyperkalemia per se can lead to acidosis. Here I describe the modern relationship between molecular function of the distal portion of the nephron, pathways of ammoniagenesis, and hyperkalemia.

  4. Potencial genético de um sintético de milho de grãos duros para formação de híbridos Genetic potential of a flint maize synthetic for hybrid production

    Directory of Open Access Journals (Sweden)

    Elto Eugenio Gomes e Gama

    2003-08-01

    Full Text Available O objetivo deste estudo foi determinar através das estimativas de parâmetros genéticos o potencial de um sintético de milho de grãos duros e de ciclo semiprecoce, para a formação de híbridos e/ou melhoramento intrapopulacional. Foram utilizadas 142 progênies endogâmicas S2 do Sin EEL Flint, em cruzamentos topcrosses com um Sintético heteroticamente contrastante. Essas progênies topcrosses foram avaliadas utilizando-se o delineamento em látice simples 12 x 12, e em dois locais de teste. Os maiores valores médios para PED foram observados para os topcrosses n.º 101 (12069kg ha-1 e nº 72 (11068Kg ha-1, tendo o primeiro apresentado comportamento específico para Londrina, e o segunda demonstrado comportamento superior nos dois ambientes. Os valores das estimativas dos parâmetros estudados foram semelhantes aos encontrados em alguns estudos conduzidos em condições tropicais. O grupo de progênies S2 da Sin EEL Flint conduziu a valores médios de , CVg e h² similares aos encontrados na literatura para outros genótipos. Observa-se que esse Sintético possui suficiente variabilidade genética e potencial para extração de linhagens para formação de híbridos e como germoplasma em programas de melhoramento.The objective of this study was to determine the genetic potential of a semi-early maize synthetic with flint type kernel (Sin EEL Flint. The estimation of genetic parameters was obtained with S2 progenies, and the performance of the progenies in hybrid combinations were evaluated. One hundred fourty-two S2 progenies of Sin EEL Flint were used. They were obtained by top crossings with a contrasting heterotic synthetic of dent type kernel. These topcross progenies were tested in a lattice design 12 x 12 with two replications in two locations, Sete Lagoas and Londrina. The selected topcross nº 101, with specific adaptation for Londrina. and nº72, being adapted to both locations, were the best yieldings (PED with 12069Kg ha-1 and

  5. Synthetic Cannabinoids.

    Science.gov (United States)

    Mills, Brooke; Yepes, Andres; Nugent, Kenneth

    2015-07-01

    Synthetic cannabinoids (SCBs), also known under the brand names of "Spice," "K2," "herbal incense," "Cloud 9," "Mojo" and many others, are becoming a large public health concern due not only to their increasing use but also to their unpredictable toxicity and abuse potential. There are many types of SCBs, each having a unique binding affinity for cannabinoid receptors. Although both Δ-tetrahydrocannabinol (THC) and SCBs stimulate the same receptors, cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2), studies have shown that SCBs are associated with higher rates of toxicity and hospital admissions than is natural cannabis. This is likely due to SCBs being direct agonists of the cannabinoid receptors, whereas THC is a partial agonist. Furthermore, the different chemical structures of SCBs found in Spice or K2 may interact in unpredictable ways to elicit previously unknown, and the commercial products may have unknown contaminants. The largest group of users is men in their 20s who participate in polydrug use. The most common reported toxicities with SCB use based on studies using Texas Poison Control records are tachycardia, agitation and irritability, drowsiness, hallucinations, delusions, hypertension, nausea, confusion, dizziness, vertigo and chest pain. Acute kidney injury has also been strongly associated with SCB use. Treatment mostly involves symptom management and supportive care. More research is needed to identify which contaminants are typically found in synthetic marijuana and to understand the interactions between different SBCs to better predict adverse health outcomes.

  6. Natural - synthetic - artificial!

    DEFF Research Database (Denmark)

    Nielsen, Peter E

    2010-01-01

    The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life.......The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life....

  7. Behavior of horizontally curved steel tubular-flange bridge girders

    Science.gov (United States)

    Fan, Zhuo

    A new type of curved steel bridge girder, called a curved tubular-flange girder, with rectangular tubes as flanges, is proposed and studied in this dissertation. A curved steel tubular-flange girder has much larger torsional stiffness than a curved I-girder and less potential for cross section distortion than a curved box-girder. Therefore, it has potential advantages compared to curved I-girders and box-girders. A theoretical analysis method for systems of curved tubular-flange girders braced by cross frames is presented. A stress analysis method for tubular-flange girders is also provided. The behavior of curved tubular-flange girder systems is studied using the theoretical analysis method and compared to the behavior of the corresponding curved I-girder systems. A parametric study is performed using the theoretical analysis method to investigate the effects of geometric parameters on the behavior of curved tubular-flange girder systems. The studied parameters include tubular-flange width, tubular-flange depth, cross section depth, girder curvature, and the number of cross frames. Finite element analyses are conducted to verify the theoretical analysis method, to study the behavior of a curved tubular-flange girder system under dead load, and to study the behavior of a curved tubular-flange girder system with a composite concrete deck under dead and live load. The study shows that a curved tubular-flange girder system develops much less warping normal stress and cross section rotation than a corresponding curved I-girder system. The difference is especially significant for a single curved girder under its own weight, suggesting that curved tubular-flange girders would be much easier to transport and erect than curved I-girders. As girder curvature increases, the rate of increase in the stresses and displacements for a single I-girder is much greater than for a single curved tubular-flange girder. Smaller cross frame forces develop in a tubular-flange girder

  8. Luminal nucleotides are tonic inhibitors of renal tubular transport

    DEFF Research Database (Denmark)

    Leipziger, Jens Georg

    2011-01-01

    PURPOSE OF REVIEW: Extracellular ATP is an essential local signaling molecule in all organ systems. In the kidney, purinergic signaling is involved in an array of functions and this review highlights those of relevance for renal tubular transport. RECENT FINDINGS: Purinergic receptors are expressed...... in all renal tubular segments and their stimulation generally leads to transport inhibition. Recent evidence has identified the tubular lumen as a restricted space for purinergic signaling. The concentrations of ATP in the luminal fluids are sufficiently high to inflict a tonic inhibition of renal...... tubular absorption via P2 receptors. The apical P2Y2 receptor plays a crucial role in this process. ATP is released continuously into the tubular lumen. The release is augmented in response to an increase of tubular flow and after stimulation of G-protein-coupled receptors. The primary cilium appears...

  9. Synthetic Brainbows

    KAUST Repository

    Wan, Y.

    2013-06-01

    Brainbow is a genetic engineering technique that randomly colorizes cells. Biological samples processed with this technique and imaged with confocal microscopy have distinctive colors for individual cells. Complex cellular structures can then be easily visualized. However, the complexity of the Brainbow technique limits its applications. In practice, most confocal microscopy scans use different florescence staining with typically at most three distinct cellular structures. These structures are often packed and obscure each other in rendered images making analysis difficult. In this paper, we leverage a process known as GPU framebuffer feedback loops to synthesize Brainbow-like images. In addition, we incorporate ID shuffing and Monte-Carlo sampling into our technique, so that it can be applied to single-channel confocal microscopy data. The synthesized Brainbow images are presented to domain experts with positive feedback. A user survey demonstrates that our synthetic Brainbow technique improves visualizations of volume data with complex structures for biologists.

  10. Tubular occlusion optimizes bonding of hydrophobic resins to dentin.

    Science.gov (United States)

    Sadek, F T; Pashley, D H; Ferrari, M; Tay, F R

    2007-06-01

    Although hydrophobic resins may be bonded to acid-etched dentin with an ethanol wet-bonding technique, the protocol is sensitive to moisture contamination when bonding is performed in deep dentin. This study tested the hypothesis that the use of oxalate or poly(glutamic) acid-modified, diluted ceramicrete (PADC) for dentinal tubule occlusion prevents fluid contamination and improves the bonding of an experimental hydrophobic adhesive to acid-etched, ethanol-dehydrated dentin. Mid-coronal and deep acid-etched moist dentin pre-treated with oxalate or PADC was dehydrated by ethanol wet-bonding and infiltrated with the experimental three-step etch-and-rinse hydrophobic adhesive under simulated pulpal pressure. Tensile bond strengths to deep dentin without pre-treatment were severely compromised. Conversely, oxalate and PADC pre-treatments reduced dentin permeability, prevented water contamination, and improved bond strengths. Minimal nanoleakage was identified within hybrid layers created in the oxalate- and PADC-pre-treated deep dentin. The use of tubular occluding agents optimized bonding of hydrophobic resins to dentin.

  11. Design and Analysis of Tubular Permanent Magnet Linear Wave Generator

    Directory of Open Access Journals (Sweden)

    Jikai Si

    2014-01-01

    Full Text Available Due to the lack of mature design program for the tubular permanent magnet linear wave generator (TPMLWG and poor sinusoidal characteristics of the air gap flux density for the traditional surface-mounted TPMLWG, a design method and a new secondary structure of TPMLWG are proposed. An equivalent mathematical model of TPMLWG is established to adopt the transformation relationship between the linear velocity of permanent magnet rotary generator and the operating speed of TPMLWG, to determine the structure parameters of the TPMLWG. The new secondary structure of the TPMLWG contains surface-mounted permanent magnets and the interior permanent magnets, which form a series-parallel hybrid magnetic circuit, and their reasonable structure parameters are designed to get the optimum pole-arc coefficient. The electromagnetic field and temperature field of TPMLWG are analyzed using finite element method. It can be included that the sinusoidal characteristics of air gap flux density of the new secondary structure TPMLWG are improved, the cogging force as well as mechanical vibration is reduced in the process of operation, and the stable temperature rise of generator meets the design requirements when adopting the new secondary structure of the TPMLWG.

  12. Design and analysis of tubular permanent magnet linear wave generator.

    Science.gov (United States)

    Si, Jikai; Feng, Haichao; Su, Peng; Zhang, Lufeng

    2014-01-01

    Due to the lack of mature design program for the tubular permanent magnet linear wave generator (TPMLWG) and poor sinusoidal characteristics of the air gap flux density for the traditional surface-mounted TPMLWG, a design method and a new secondary structure of TPMLWG are proposed. An equivalent mathematical model of TPMLWG is established to adopt the transformation relationship between the linear velocity of permanent magnet rotary generator and the operating speed of TPMLWG, to determine the structure parameters of the TPMLWG. The new secondary structure of the TPMLWG contains surface-mounted permanent magnets and the interior permanent magnets, which form a series-parallel hybrid magnetic circuit, and their reasonable structure parameters are designed to get the optimum pole-arc coefficient. The electromagnetic field and temperature field of TPMLWG are analyzed using finite element method. It can be included that the sinusoidal characteristics of air gap flux density of the new secondary structure TPMLWG are improved, the cogging force as well as mechanical vibration is reduced in the process of operation, and the stable temperature rise of generator meets the design requirements when adopting the new secondary structure of the TPMLWG.

  13. Distal Renal Tubular Acidosis and Calcium Nephrolithiasis

    Science.gov (United States)

    Moe, Orson W.; Fuster, Daniel G.; Xie, Xiao-Song

    2008-09-01

    Calcium stones are commonly encountered in patients with congenital distal renal tubular acidosis, a disease of renal acidification caused by mutations in either the vacuolar H+-ATPase (B1 or a4 subunit), anion exchanger-1, or carbonic anhydrase II. Based on the existing database, we present two hypotheses. First, heterozygotes with mutations in B1 subunit of H+-ATPase are not normal but may harbor biochemical abnormalities such as renal acidification defects, hypercalciuria, and hypocitraturia which can predispose them to kidney stone formation. Second, we propose at least two mechanisms by which mutant B1 subunit can impair H+-ATPase: defective pump assembly and defective pump activity.

  14. Flangeless Connections in Steel Tubular Wind Towers

    OpenAIRE

    Heistermann, Christine; Tran, Anh Tuan; Veljkovic, Milan, ed. lit.; Rebelo, Carlos

    2014-01-01

    Extensive research is conducted on the improvement of renewable energies. One field is the use of wind energy, where the tower construction is one of the main issues. This paper deals with new ideas and ongoing research in this area. To raise the height of steel tubular towers, fatigue as the design limit and constraints due to transportation issues have to be overcome. Changes in the cross-section are considered as one of possible solutions. This work presents an extensive finite element stu...

  15. Geometric optimization of a solar cubic-cavity multi-tubular reactor

    Science.gov (United States)

    Valades-Pelayo, P. J.; Arancibia-Bulnes, C. A.; Villafan-Vidales, H.; Romero-Paredes, H.

    2016-05-01

    A multi-tubular solar thermochemical cavity reactor is proposed and the tubular array optimized. The optimized reactor design aims at operating under different temperatures and carrying out different kinds of thermochemical reactions. The radiation entering the receptacle comes from a solar concentrating system and the reactor consists of a cubic receptacle made of woven graphite, housing nine 2.54 cm diameter tungsten tubes. A model is developed and implemented considering high-temperature radiative transfer at steady state. The temperature distribution within the cavity surfaces is determined by employing a hybrid Monte Carlo-Finite Volume approach. Optimal tube distributions are explored by using a custom-made stochastic, multi-parameter, optimization algorithm. In this way, multiple global maxima are determined. Patterns among all possible optimal tube distributions within the cavity are obtained for different scenarios, by maximizing average tube temperature. From this study, practical guidelines are obtained for future application in the design of solar cavity reactors and more specifically, on the layout of multi tubular arrays to optimize radiative heat transfer.

  16. Role of the glomerular-tubular imbalance with tubular predominance in the arterial hypertension pathophysiology.

    Science.gov (United States)

    Fox, María Ofelia Barber; Gutiérrez, Ernesto Barber

    2013-09-01

    In previous investigations we caused renal tubular reabsorption preponderance relating to the glomerular filtration (Glomerular-tubular imbalance) and we observed that this fact conducted to volume expansion and development of arterial hypertension, in rats that previously were normotens. We based on this evidence and other which are reflected in the literature arrived at the following hypothesis: a greater proportion of tubular reabsorption relating to the filtered volume is the base of the establishment of the glomerular-tubular imbalance with tubular predominance (GTI-T), which favors to the Na(+)-fluid retention and volume expansion. All of which conduced to arterial hypertension. These facts explain a primary hypertensive role of the kidney, consistent with the results of renal transplants performed in different lines of hypertensive rats and their respective controls and in humans: hypertension can be transferred with the kidney. GTI-T aims to be, a common phenomenon involved in the hypertension development in the multiple ways which is manifested the hypertensive syndrome. In secondary hypertension, GTI-T is caused by significant disruptions of hormone secretions that control renal function, or obvious vascular or parenchymal damage of these organs. In primary hypertension the GTI-T has less obvious causes inherently developed in the kidney, including humoral, cellular and subcellular mechanisms, which may insidiously manifest under environmental factors influence, resulting in insidious development of hypertension. This would explain the state of prehypertension that these individuals suffer. So it has great importance to study GTI-T before the hypertension is established, because when hypertensive state is established, other mechanisms are installed and they contribute to maintain the hypertension. Our hypothesis may explaining the inability of the kidneys to excrete salt and water in hypertension, as Guyton and colleagues have expressed and constitutes a

  17. Synthetic Astrobiology

    Science.gov (United States)

    Rothschild, Lynn J.

    2017-01-01

    "Are we alone?" is one of the primary questions of astrobiology, and whose answer defines our significance in the universe. Unfortunately, this quest is hindered by the fact that we have only one confirmed example of life, that of earth. While this is enormously helpful in helping to define the minimum envelope for life, it strains credulity to imagine that life, if it arose multiple times, has not taken other routes. To help fill this gap, our lab has begun using synthetic biology - the design and construction of new biological parts and systems and the redesign of existing ones for useful purposes - as an enabling technology. One theme, the "Hell Cell" project, focuses on creating artificial extremophiles in order to push the limits for Earth life, and to understand how difficult it is for life to evolve into extreme niches. In another project, we are re-evolving biotic functions using only the most thermodynamically stable amino acids in order to understand potential capabilities of an early organism with a limited repertoire of amino acids.

  18. The syndrome of renal tubular acidosis with nerve deafness.

    Science.gov (United States)

    Donckerwolcke, R A; Van Biervliet, J P; Koorevaar, G; Kuijten, R H; Van Stekelenburg, G J

    1976-01-01

    Two brothers with renal tubular acidosis and nerve deafness are described. Studies of the physiopathological characteristics of the renal acidification defect show that the defect is limited to the distal tubule. Renal tubular acidosis with nerve deafness is a distinct nosologic entity that is determined by an autosomal recessive trait.

  19. Complement activation by tubular cells is mediated by properdin binding

    NARCIS (Netherlands)

    Gaarkeuken, E.M.; Siezenga, M.A.; Zuidwijk, K.; Kooten, C. van; Rabelink, T.J.; Daha, M.R.; Berger, S.P.

    2008-01-01

    Activation of filtered complement products on the brush border of the tubular epithelium is thought to be a key factor underlying proteinuria-induced tubulointerstitial injury. However, the mechanism of tubular complement activation is still unclear. Recent studies on mechanisms of complement activa

  20. Theoretical and experimental investigations of Chinese evacuated tubular solar collectors

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1999-01-01

    Four different marketed Chinese evacuated tubular solar collectors have been investigated both theoretically and experimentally. The advantages of the investigated solar collectors compared to normal flat plate collectors were elucidated.......Four different marketed Chinese evacuated tubular solar collectors have been investigated both theoretically and experimentally. The advantages of the investigated solar collectors compared to normal flat plate collectors were elucidated....

  1. Tubular initial conditions and ridge formation

    CERN Document Server

    Borysova, M S; Karpenko, Iu A; Shapoval, V M; Sinyukov, Yu M

    2013-01-01

    The 2D azimuth & rapidity structure of the two-particle correlations in relativistic A+A collisions is altered significantly by the presence of sharp inhomogeneities in superdense matter formed in such processes. The causality constraints enforce one to associate the long-range longitudinal correlations observed in a narrow angular interval, the so-called (soft) ridge, with peculiarities of the initial conditions of collision process. This study's objective is to analyze whether multiform initial tubular structures, undergoing the subsequent hydrodynamic evolution and gradual decoupling, can form the soft ridges. Motivated by the flux-tube scenarios, the initial energy density distribution contains the different numbers of high density tube-like boost-invariant inclusions that form a bumpy structure in the transverse plane. The influence of various structures of such initial conditions in the most central A+A events on the collective evolution of matter, resulting spectra, angular particle correlations an...

  2. Inherited renal tubular defects with hypokalemia

    Directory of Open Access Journals (Sweden)

    Muthukrishnan J

    2009-01-01

    Full Text Available Bartter′s and Gitelman′s syndrome are two ends of a spectrum of inherited renal tubular disorders that present with hypokalemic metabolic alkalosis of varying severity. Clinical features and associated calcium and magnesium ion abnormalities are used to diagnose these cases after excluding other commoner causes. We report on two cases, the first being a young boy, born of pregnancy complicated by polyhydramnios, who had classical dysmorphic features, polyuria, hypokalemia and hypercalciuria and was diagnosed as having Bartter′s syndrome. The second patient is a lady who had recurrent tetany as the only manifestation of Gitelman′s syndrome, which is an unusual presentation. Potassium replacement with supplementation of other deficient ions led to satisfactory clinical and biochemical response.

  3. Multiplicity features of nonadiabatic, autothermal tubular reactors

    Energy Technology Data Exchange (ETDEWEB)

    Lovo, M.; Balakotaiah, V. (Houston Univ., TX (United States). Dept. of Chemical Engineering)

    1992-01-01

    Singularity theory is combined with asymptotic analysis to determine the exact uniqueness-multiplicity boundary and ignition and extinction locus for the non-adiabatic, autothermal tubular reactor model. It is found that the steady-state behavior of the nonadiabatic reactor is described by the two limiting cases of adiabatic and strongly cooled models. The adiabatic case has been examined in a previous study. In this paper, the authors develop limiting models to describe the strongly cooled asymptotes. The authors also classify the different types of bifurcation diagrams of conversion vs. residence time using the results of singularity theory with a distinguished parameter. Analytical criteria are developed for predicting the conditions under which autothermal operation is feasible when heat losses are significant.

  4. Cytocompatibility of a silk fibroin tubular scaffold

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jiannan, E-mail: wangjn@suda.edu.cn; Wei, Yali; Yi, Honggen; Liu, Zhiwu; Sun, Dan; Zhao, Huanrong

    2014-01-01

    Regenerated silk fibroin (SF) materials are increasingly used for tissue engineering applications. In order to explore the feasibility of a novel biomimetic silk fibroin tubular scaffold (SFTS) crosslinked by poly(ethylene glycol) diglycidyl ether (PEG-DE), biocompatibility with cells was evaluated. The novel biomimetic design of the SFTS consisted of three distinct layers: a regenerated SF intima, a silk braided media and a regenerated SF adventitia. The SFTS exhibited even silk fibroin penetration throughout the braid, forming a porous layered tube with superior mechanical, permeable and cell adhesion properties that are beneficial to vascular regeneration. Cytotoxicity and cell compatibility were tested on L929 cells and human umbilical vein endothelial cells (EA.hy926). DNA content analysis, scanning electron and confocal microscopies and MTT assay showed no inhibitory effects on DNA replication. Cell morphology, viability and proliferation were good for L929 cells, and satisfactory for EA.hy926 cells. Furthermore, the suture retention strength of the SFTS was about 23 N and the Young's modulus was 0.2–0.3 MPa. Collectively, these data demonstrate that PEG-DE crosslinked SFTS possesses the appropriate cytocompatibility and mechanical properties for use as vascular scaffolds as an alternative to vascular autografts. - Highlights: • A PEG-DE cross-linked small caliber porous silk fibroin tubular scaffold (SFTS) • PEG-DE cross-linked SF film had no inhibitory effect on DNA replication of cells. • Cells cultured on the SFTS showed good morphology, cell viability and proliferative activity. • SFTS would be beneficial to endothelialization. • SFTS had good suture retention strength and flexibility.

  5. Efficient engineering of marker-free synthetic allotetraploids of Saccharomyces.

    Science.gov (United States)

    Alexander, William G; Peris, David; Pfannenstiel, Brandon T; Opulente, Dana A; Kuang, Meihua; Hittinger, Chris Todd

    2016-04-01

    Saccharomyces interspecies hybrids are critical biocatalysts in the fermented beverage industry, including in the production of lager beers, Belgian ales, ciders, and cold-fermented wines. Current methods for making synthetic interspecies hybrids are cumbersome and/or require genome modifications. We have developed a simple, robust, and efficient method for generating allotetraploid strains of prototrophic Saccharomyces without sporulation or nuclear genome manipulation. S. cerevisiae×S. eubayanus, S. cerevisiae×S. kudriavzevii, and S. cerevisiae×S. uvarum designer hybrid strains were created as synthetic lager, Belgian, and cider strains, respectively. The ploidy and hybrid nature of the strains were confirmed using flow cytometry and PCR-RFLP analysis, respectively. This method provides an efficient means for producing novel synthetic hybrids for beverage and biofuel production, as well as for constructing tetraploids to be used for basic research in evolutionary genetics and genome stability. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Tubular Peroxiredoxin 3 as a Predictor of Renal Recovery from Acute Tubular Necrosis in Patients with Chronic Kidney Disease.

    Science.gov (United States)

    Wu, Chia-Lin; Su, Tzu-Cheng; Chang, Chia-Chu; Kor, Chew-Teng; Chang, Chung-Ho; Yang, Tao-Hsiang; Chiu, Ping-Fang; Tarng, Der-Cherng

    2017-02-27

    Peroxiredoxin 3 (PRX3) is a mitochondrial antioxidant that regulates apoptosis in various cancers. However, whether tubular PRX3 predicts recovery of renal function following acute kidney injury (AKI) remains unknown. This retrospective cohort study included 54 hospitalized patients who had AKI with biopsy-proven acute tubular necrosis (ATN). The study endpoint was renal function recovery within 6 months. Of the 54 enrolled patients, 25 (46.3%) had pre-existing chronic kidney disease (CKD) and 33 (61%) recovered renal function. Tubular PRX3 expression was higher in patients with ATN than in those without renal function recovery. The level of tubular but not glomerular PRX3 expression predicted renal function recovery from AKI (AUROC = 0.76). In multivariate Cox regression analysis, high PRX3 expression was independently associated with a higher probability of renal function recovery (adjusted hazard ratio = 8.99; 95% CI 1.13-71.52, P = 0.04). Furthermore, the discriminative ability of the clinical model for AKI recovery was improved by adding tubular PRX3. High tubular PRX3 expression was associated with a higher probability of renal function recovery from ATN. Therefore, tubular PRX3 in combination with conventional predictors can further improve recovery prediction and may help with risk stratification in AKI patients with pre-existing CKD.

  7. Local synthesis of interferon-alpha in lupus nephritis is associated with type I interferons signature and LMP7 induction in renal tubular epithelial cells.

    Science.gov (United States)

    Castellano, Giuseppe; Cafiero, Cesira; Divella, Chiara; Sallustio, Fabio; Gigante, Margherita; Pontrelli, Paola; De Palma, Giuseppe; Rossini, Michele; Grandaliano, Giuseppe; Gesualdo, Loreto

    2015-03-22

    Type I interferons are pivotal in the activation of autoimmune response in systemic lupus erythematous. However, the pathogenic role of interferon-alpha in patients affected by lupus nephritis remains uncertain. The aim of our study was to investigate the presence of a specific interferon signature in lupus nephritis and the effects of interferon-alpha at renal level. We performed immunohistochemical analysis for MXA-protein and in situ hybridization to detect interferon-alpha signature and production in human lupus nephritis. Through microarray studies, we analyzed the gene expression profile of renal tubular epithelial cells, stimulated with interferon-alpha. We validated microarray results through real-time polymerase chain reaction, flow cytometry on renal tubular epithelial cells, and through immunohistochemical analysis and confocal microscopy on renal biopsies. Type I interferons signature was characterized by MXA-specific staining in renal tubular epithelial cells; in addition, in situ hybridization showed that renal tubular epithelial cells were the major producers of interferon-alpha, indicating a potential autocrine effect. Whole-genome expression profile showed interferon-alpha induced up-regulation of genes involved in innate immunity, protein ubiquitination and switching to immunoproteasome. In accordance with the in vitro data, class IV lupus nephritis showed up-regulation of the immunoproteasome subunit LMP7 in tubular epithelial cells associated with type I interferon signature. Our data indicate that type I interferons might have a pathogenic role in lupus nephritis characterized by an autocrine effect of interferon-alpha on renal tubular epithelial cells. Therefore we hypothesize that inhibition of type I interferons might represent a therapeutic target to prevent tubulo-interstitial damage in patients with lupus nephritis.

  8. Energy production with a tubular propeller turbine

    Science.gov (United States)

    Samora, I.; Hasmatuchi, V.; Münch-Alligné, C.; Franca, M. J.; Schleiss, A. J.; Ramos, H. M.

    2016-11-01

    Micro-hydropower is a way of improving the energetic efficiency of existent water systems. In the particular case of drinking water systems, several studies have showed that pressure reducing valves can be by-passed with turbines in order to recover the dissipated hydraulic energy to produce electricity. As conventional turbines are not always cost-effective for power under 20 kW, a new energy converter is studied. A five blade tubular propeller (5BTP), assessed through laboratorial tests on a reduced model with a diameter of 85 mm diameter and a maximal output power of 300 W, is addressed in this work. Having showed promising potential for further development, since global efficiencies of around 60% were observed, the turbine has been further used to estimate the potential for energy production in a real case study. A sub-grid of the drinking water system of the city of Lausanne, Switzerland, has been used to obtain an annual energy production through hourly simulations with several turbines.

  9. The Fourier transform of tubular densities

    KAUST Repository

    Prior, C B

    2012-05-18

    We consider the Fourier transform of tubular volume densities, with arbitrary axial geometry and (possibly) twisted internal structure. This density can be used to represent, among others, magnetic flux or the electron density of biopolymer molecules. We consider tubes of both finite radii and unrestricted radius. When there is overlap of the tube structure the net density is calculated using the super-position principle. The Fourier transform of this density is composed of two expressions, one for which the radius of the tube is less than the curvature of the axis and one for which the radius is greater (which must have density overlap). This expression can accommodate an asymmetric density distribution and a tube structure which has non-uniform twisting. In addition we give several simpler expressions for isotropic densities, densities of finite radius, densities which decay at a rate sufficient to minimize local overlap and finally individual surfaces of the tube manifold. These simplified cases can often be expressed as arclength integrals and can be evaluated using a system of first-order ODEs. © 2012 IOP Publishing Ltd.

  10. Pressure driven flow in porous tubular membranes

    Science.gov (United States)

    Tilton, Nils; Martinand, Denis; Serre, Eric; Lueptow, Richard

    2011-11-01

    We consider the steady laminar flow of a Newtonian incompressible fluid in a porous tubular membrane with pressure-driven transmembrane flow. Due to its fundamental importance to membrane filtration systems, this flow has been studied extensively both analytically and numerically, yet a robust analytic solution has not been found. The problem is challenging due to the coupling between the transmembrane pressure and velocity with the simultaneous coupling between the axial pressure gradient and the axial velocity. We present a robust analytical solution which incorporates Darcy's law on the membrane surface. The solution is in the form of an asymptotic expansion about a small parameter related to the membrane permeability. We verify the analytical solution with comparison to 2-D spectral direct numerical simulations of ultrafiltration and microfiltration systems with typical operating conditions, as well as extreme cases of cross-flow reversal and axial flow exhaustion. In all cases, the agreement between the analytical and numerical results is excellent. Finally, we use the analytical and numerical results to provide guidelines about when common simplifying assumptions about the permeate flow may be made. Specifically, the assumptions of a parabolic axial velocity profile and uniform transmembrane velocity are valid only for small permeabilities.

  11. Tubular heart valves from decellularized engineered tissue.

    Science.gov (United States)

    Syedain, Zeeshan H; Meier, Lee A; Reimer, Jay M; Tranquillo, Robert T

    2013-12-01

    A novel tissue-engineered heart valve (TEHV) was fabricated from a decellularized tissue tube mounted on a frame with three struts, which upon back-pressure cause the tube to collapse into three coapting "leaflets." The tissue was completely biological, fabricated from ovine fibroblasts dispersed within a fibrin gel, compacted into a circumferentially aligned tube on a mandrel, and matured using a bioreactor system that applied cyclic distension. Following decellularization, the resulting tissue possessed tensile mechanical properties, mechanical anisotropy, and collagen content that were comparable to native pulmonary valve leaflets. When mounted on a custom frame and tested within a pulse duplicator system, the tubular TEHV displayed excellent function under both aortic and pulmonary conditions, with minimal regurgitant fractions and transvalvular pressure gradients at peak systole, as well as well as effective orifice areas exceeding those of current commercially available valve replacements. Short-term fatigue testing of one million cycles with pulmonary pressure gradients was conducted without significant change in mechanical properties and no observable macroscopic tissue deterioration. This study presents an attractive potential alternative to current tissue valve replacements due to its avoidance of chemical fixation and utilization of a tissue conducive to recellularization by host cell infiltration.

  12. Muscle MR imaging in tubular aggregate myopathy.

    Directory of Open Access Journals (Sweden)

    Valeria Beltrame

    Full Text Available PURPOSE: To evaluate with Magnetic Resonance (MR the degree of fatty replacement and edematous involvement in skeletal muscles in patients with Tubular Aggregate Myopathy (TAM. To asses the inter-observer agreement in evaluating muscle involvement and the symmetry index of fatty replacement. MATERIALS AND METHODS: 13 patients were evaluated by MR to ascertain the degree of fatty replacement (T1W sequences according to Mercuri's scale, and edema score (STIR sequences according to extent and site. RESULTS: Fatty replacement mainly affects the posterior superficial compartment of the leg; the anterior compartment is generally spared. Edema was generally poor and almost only in the superficial compartment of the leg. The inter-observer agreement is very good with a Krippendorff's coefficient >0.9. Data show a total symmetry in the muscular replacement (McNemar-Bowker test with p = 1. CONCLUSIONS: MR reveals characteristic muscular involvement, and is a reproducible technique for evaluation of TAM. There may also be a characteristic involvement of the long and short heads of the biceps femoris. It is useful for aimed biopsies, diagnostic hypotheses and evaluation of disease progression.

  13. Tubular Steel Arch Stabilized by Textile Membranes

    Directory of Open Access Journals (Sweden)

    Ondrej Svoboda

    2016-10-01

    Full Text Available Tubular steel arch supporting textile membrane roofing is investigated experimentally and numerically. The stabilization effects of the textile membrane on in-plane and out-of-plane behavior of the arch is of primary interest. First a model of a large membrane structure tested in laboratory is described. Prestressed membranes of PVC coated polyester fabric Ferrari® Précontraint 702S were used as a currently standard and excellent material. The test arrangement, loading and resulting load/deflection values are presented. The supporting structure consisted of two steel arch tubes, outer at edge of the membrane and inner supporting interior of the membrane roofing. The stability and strength behavior of the inner tube under both symmetrical and asymmetrical loading was monitored and is shown in some details. Second the SOFiSTiK software was employed to analyze the structural behavior in 3D, using geometrically nonlinear analysis with imperfections (GNIA. The numerical analysis, FE mesh sensitivity, the membrane prestressing and common boundary conditions are validated by test results. Finally a parametrical study concerning stability of mid arch with various geometries in a membrane structure with several supporting arches is presented, with recommendations for a practical design.

  14. A tubular electrode for radiofrequency ablation therapy

    KAUST Repository

    Antunes, Carlos Lemos Lemos Lemos

    2012-07-06

    Purpose – Due to its good mechanical and biocompatibility characteristics, nitinol SEMS is a popular endoprothesis used for relieving stricture problems in hollow organs due to carcinomas. Besides its mechanical application, SEMS can be regarded as well as potential electrode for performing RF ablation therapy on the tumor. The purpose of this work is to perform numerical and experimental analyses in order to characterize the lesion volume induced in biological tissue using this kind of tubular electrode. Design/methodology/approach – Data concerning electrical conductivity and dimension of the damaged tissue after RF ablation procedure were obtained from ex vivo samples. Next, numerical models using 3D finite element method were obtained reassembling the conditions considered at experimentation setup and results were compared. Findings – Numerical and experimental results show that a regular volume of damaged tissue can be obtained considering this type of electrode. Also, results obtained from numerical simulation are close to those obtained by experimentation. Originality/value – SEMSs, commonly used as devices to minimize obstruction problems due to the growth of tumors, may still be considered as an active electrode for RF ablation procedures. A method considering this observation is presented in this paper. Also, numerical simulation can be regarded in this case as a tool for determining the lesion volume.

  15. Scenario analysis of large scale algae production in tubular photobioreactors

    NARCIS (Netherlands)

    Slegers, P.M.; Beveren, van P.J.M.; Wijffels, R.H.; Straten, van G.; Boxtel, van A.J.B.

    2013-01-01

    Microalgae productivity in tubular photobioreactors depends on algae species, location, tube diameter, biomass concentration, distance between tubes and for vertically stacked systems, the number of horizontal tubes per stack. A simulation model for horizontal and vertically stacked horizontal tubul

  16. Elastic Deployable Composite Tubular Roll-Out Boom Project

    Data.gov (United States)

    National Aeronautics and Space Administration — DSS's innovative Elastic Deployable Composite Tubular Roll-Out Boom will provide revolutionary performance when compared to conventional state-of-the-art...

  17. Intrarenal purinergic signaling in the control of renal tubular transport

    DEFF Research Database (Denmark)

    Prætorius, Helle; Leipziger, Jens Georg

    2010-01-01

    Renal tubular epithelial cells receive hormonal input that regulates volume and electrolyte homeostasis. In addition, numerous intrarenal, local signaling agonists have appeared on the stage of renal physiology. One such system is that of intrarenal purinergic signaling. This system involves all...... the elements necessary for agonist-mediated intercellular communication. ATP is released from epithelial cells, which activates P2 receptors in the apical and basolateral membrane and thereby modulates tubular transport. Termination of the signal is conducted via the breakdown of ATP to adenosine. Recent far......-reaching advances indicate that ATP is often used as a local transmitter for classical sensory transduction. This transmission apparently also applies to sensory functions in the kidney. Locally released ATP is involved in sensing of renal tubular flow or in detecting the distal tubular load of NaCl at the macula...

  18. Fatigue Life of High-Strength Steel Offshore Tubular Joints

    DEFF Research Database (Denmark)

    Petersen, Rasmus Ingomar; Agerskov, Henning; Lopez Martinez, Luis

    1996-01-01

    In the present investigation, the fatigue life of tubular joints in offshore steel structures is studied. Two test series on full-scale tubular joints have been carried through. One series was on joints in conventional offshore structural steel, and the other series was on joints in high-strength...... steel with a yield stress of 820-830 MPa and with high weldability and toughness properties. The test specimens of both series had the same geometry. The present report concentrates on the results obtained in the investigation on the high-strength steel tubular joints.The test specimens were fabricated...... amplitude fatigue test results showed shorter fatigue lives in variable amplitude loading than should be expected from the linear fatigue damage accumulation formula. Furthermore, the fatigue tests on high-strength steel tubular joints showed slightly longer fatigue lives than those obtained...

  19. Effect of tamoxifen on spermatogenesis and tubular morphology in rats

    Institute of Scientific and Technical Information of China (English)

    UrbanJ.A.D'Souza

    2004-01-01

    Aim: To observe the effect of tamoxifen citrate on spermatogenesis and tubular morphology in rats.Methods: The effect of tamoxifen citrate i.g. at doses of 400 and 800 mg·kg-1·day-1 in 0.1 mL olive oil for 30 days on seminiferous tubular morphology, seminiferous epithelial diameter (STD), epithelial height (SEH), epididymal sperm count and percent abnormal sperm were evaluated at day 1, 12 and 36 after treatment. Controls were given the vehicle. Results: The higher dose resulted in tubular atrophy on day 31. The STD, SEH and sperm count were decreased and the abnormal spermatozoa increased in a dose-dependent manner with the maximal effect on day 36.Conclusion: Tamoxifen citrate induces tubular shrinkage and atrophy and sperm abnormality at a dose-dependent manner. (Asian J Androl 2004 Sep; 6: 223-226)

  20. Solar Heating Systems with Evacuated Tubular Solar Collector

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1998-01-01

    , as well as with normal flat-plate collectors was calculated under Danish weather conditions. It is found that, for small SDHW systems with a combi tank design, an increase of 25% -55% net utilized solar energy can be achieved by using these evacuated tubular collectors instead of normal flat......-plate collectors. For solar heating plants, the yearly energy output from these evacuated tubular collectors is about 40%-90% higher than the output from typical flat-plate collectors at an operation temperature of about 50°C.......Recently different designed evacuated tubular solar collectors were introduced on the market by different Chinese companies. In the present study, investigations on the performance of four different Chinese evacuated tubular collectors and of solar heating systems using these collectors were...

  1. Scenario analysis of large scale algae production in tubular photobioreactors

    NARCIS (Netherlands)

    Slegers, P.M.; Beveren, van P.J.M.; Wijffels, R.H.; Straten, van G.; Boxtel, van A.J.B.

    2013-01-01

    Microalgae productivity in tubular photobioreactors depends on algae species, location, tube diameter, biomass concentration, distance between tubes and for vertically stacked systems, the number of horizontal tubes per stack. A simulation model for horizontal and vertically stacked horizontal tubul

  2. B-tubular surfaces in Lorentzian Heisenberg Group H3

    Directory of Open Access Journals (Sweden)

    Talat Körpınar

    2015-01-01

    Full Text Available In this paper, B-tubular surfaces in terms of biharmonic spacelike new type B-slant helices according to Bishop frame in the Lorentzian Heisenberg group H3 are studied. The Necessary and sufficient conditions for new type B-slant helices to be biharmonic are obtained. B-tubular surfaces in the cLorentzian Heisenberg group H3 are characterized. Additionally, main results in Figures 1, 2, 3 and 4 are illustrated.

  3. Worse Prognosis in Papillary, Compared to Tubular, Early Gastric Carcinoma

    Science.gov (United States)

    Yu, Huiping; Fang, Cheng; Chen, Lin; Shi, Jiong; Fan, Xianshan; Zou, Xiaoping; Huang, Qin

    2017-01-01

    Purpose: Papillary early gastric carcinoma (EGC) is uncommon but shows worse prognosis in our most recent study in a Chinese population with unknown reasons. The aim of the present study was to further investigate risk factors for worse prognosis in patients with papillary adenocarcinoma, compared to those with tubular adenocarcinoma. Methods: We searched the electronic pathology databank for radical gastrectomy cases over an 8-year period at a single medical center in Nanjing, China, and identified consecutive 240 EGC cases that were classified as either papillary (n=59) or tubular (n=181) EGC tumors in accordance with the World Health Organization (WHO) gastric cancer diagnosis criteria. We investigated and compared clinicopathologic risk factors for prognosis between papillary and tubular EGC groups. All patients were followed up and their 5-year survival rate was compared statistically with the Kaplan-Meier method with a log rank test. Results: Compared to tubular EGCs, papillary EGCs were significantly more common in elderly patients, more frequently occurred in the proximal stomach with protruding/elevated growth patterns, submucosal invasion, and a micropapillary component. Although lymphovascular invasion (16.9%), nodal (13.6%) and distant (11.8%) metastases in papillary EGCs were more frequent than those (8.3%, 7.2%, and 3.7%, respectively) in tubular EGCs, the differences approached but did not reach statistically significant levels. Significant risk factors for nodal metastasis included lymphovascular invasion in both EGC groups, but the ulcerative pattern and submucosal invasion only in tubular EGCs. The 5-year survival rate was significantly worse in papillary (80.5%) than in tubular (96.8%) EGCs. Conclusions: Compared to tubular EGCs, papillary EGCs diagnosed with the WHO criteria in Chinese patients were more frequent in elderly patients, proximal stomach and showed the significantly worse 5-year survival rate with more protruding/elevated growth

  4. Behaviour of concrete filled steel tubular columns under fire

    Institute of Scientific and Technical Information of China (English)

    查晓雄; 钟善桐

    2002-01-01

    A three dimensional nonlinear FE program is used to calculate the fire resistances of concrete filledsteel tubular columns under fire. The temperature distributions in the circular section fire are decided by solvingthe Fourier Transfer Equation , and the mechanical behaviour and failure of concrete filled steel tubular columnsunder fire are thus investigated, and the effects of several parameters on the fire resistance are analysed. Theresults obtained are in good agreement with the Eurocode.

  5. Tubular atrophy in the pathogenesis of chronic kidney disease progression.

    Science.gov (United States)

    Schelling, Jeffrey R

    2016-05-01

    The longstanding focus in chronic kidney disease (CKD) research has been on the glomerulus, which is sensible because this is where glomerular filtration occurs, and a large proportion of progressive CKD is associated with significant glomerular pathology. However, it has been known for decades that tubular atrophy is also a hallmark of CKD and that it is superior to glomerular pathology as a predictor of glomerular filtration rate decline in CKD. Nevertheless, there are vastly fewer studies that investigate the causes of tubular atrophy, and fewer still that identify potential therapeutic targets. The purpose of this review is to discuss plausible mechanisms of tubular atrophy, including tubular epithelial cell apoptosis, cell senescence, peritubular capillary rarefaction and downstream tubule ischemia, oxidative stress, atubular glomeruli, epithelial-to-mesenchymal transition, interstitial inflammation, lipotoxicity and Na(+)/H(+) exchanger-1 inactivation. Once a a better understanding of tubular atrophy (and interstitial fibrosis) pathophysiology has been obtained, it might then be possible to consider tandem glomerular and tubular therapeutic strategies, in a manner similar to cancer chemotherapy regimens, which employ multiple drugs to simultaneously target different mechanistic pathways.

  6. Synthetic biology, inspired by synthetic chemistry.

    Science.gov (United States)

    Malinova, V; Nallani, M; Meier, W P; Sinner, E K

    2012-07-16

    The topic synthetic biology appears still as an 'empty basket to be filled'. However, there is already plenty of claims and visions, as well as convincing research strategies about the theme of synthetic biology. First of all, synthetic biology seems to be about the engineering of biology - about bottom-up and top-down approaches, compromising complexity versus stability of artificial architectures, relevant in biology. Synthetic biology accounts for heterogeneous approaches towards minimal and even artificial life, the engineering of biochemical pathways on the organismic level, the modelling of molecular processes and finally, the combination of synthetic with nature-derived materials and architectural concepts, such as a cellular membrane. Still, synthetic biology is a discipline, which embraces interdisciplinary attempts in order to have a profound, scientific base to enable the re-design of nature and to compose architectures and processes with man-made matter. We like to give an overview about the developments in the field of synthetic biology, regarding polymer-based analogs of cellular membranes and what questions can be answered by applying synthetic polymer science towards the smallest unit in life, namely a cell.

  7. Toward high-torque electrostatic tubular motors

    Science.gov (United States)

    Helin, Philippe; Bourbon, Gilles; Minotti, Patrice; Fujita, Hiroyuki

    1999-10-01

    A new generation of electrostatic micro-motors is investigated using cooperation of arrayed direct-drive actuators. Electrostatic scratch-drive actuators (SDA), which combine active frictional contact mechanisms with electrostatic actuation, are particularly analyzed. Active polysilicon sheets of 2*3 mm2 that integrate up to several thousands of electrostatic scratch drive actuators are fabricated by silicon surface micro-machining process. Each elementary actuator provides its contribution according to the driving force superposition principle, with internal forces as high as 105uN are available from this sheet. According to their natural flexibility, active polysilicon sheets can be coated onto large surfaces. A new generation of self-assembled tubular electrostatic micromotors is developed using this concept. A prototype of a cylindrical micromotor, whose external diameter and length are 1 mm and 2 mm, respectively, has been realized through the insertion of a flexible active polysilicon sheet at the rotor/motor- frame interface. After final assembling, the sheet has to be jammed onto the chassis, in order to allow the rotor to be moved with respect to the motor frame. Thus, the sheet must be in close contact with both the rotor and the motor frame, whatever the gap, which separates the two macroscopic parts. The problem related to the micro/macro world interfacing is solved during the design of sheet in allowing an out-of- plane motion of SDA in order to provide a self gap compensation, whatever both the thermal expansion effects and the macroscopic machining tolerances. The expected driving characteristics show the interest of both cooperative arrayed microactuators and direct drive frictional mechanisms.

  8. Helical nanostructure of tubular metal-organic complex synthesized by sonochemical process

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Tubular metal-organic complex (C2H9N2)2(C2H10N2)0.5[MoO2(OC6H4O)2] has been synthesized. The title complex crystallizes in the tetragonal system, space group P4(2)/n with a = 25.214(8), c = 7.484(4) ?, and Z = 8. The X-ray structural analysis of the complex reveals tube-like framework which is stabilized by hydrogen bond. Chiral anions [Mo(V)O2(OC6H4O)2]3? of the complex have two types of isomers(λ /δ configuration). Helical nanostructure of this metal-organic complex was formed using a sonochemical method. Sonocation may lead to the transformation from the bulk tubular complex to the helical nanostructure. The as-synthesized nanohelices were all double-stranded and left- and right-handed nanohelices were both formed. The helical nanostructure is a new morphology of inorganic-organic hybrid materials on the nanoscale level and the exact formation mechanism of these helices still needs further investigation.

  9. Plant synthetic biology.

    Science.gov (United States)

    Liu, Wusheng; Stewart, C Neal

    2015-05-01

    Plant synthetic biology is an emerging field that combines engineering principles with plant biology toward the design and production of new devices. This emerging field should play an important role in future agriculture for traditional crop improvement, but also in enabling novel bioproduction in plants. In this review we discuss the design cycles of synthetic biology as well as key engineering principles, genetic parts, and computational tools that can be utilized in plant synthetic biology. Some pioneering examples are offered as a demonstration of how synthetic biology can be used to modify plants for specific purposes. These include synthetic sensors, synthetic metabolic pathways, and synthetic genomes. We also speculate about the future of synthetic biology of plants.

  10. Synthetic Cathinones ("Bath Salts")

    Science.gov (United States)

    ... A recent study found that 3,4-methylenedioxypyrovalerone (MDPV), a common synthetic cathinone, affects the brain in ... but is at least 10 times more powerful. MDPV is the most common synthetic cathinone found in ...

  11. What Are Synthetic Cannabinoids?

    Science.gov (United States)

    ... dried plant materials. Chemical tests show that their active ingredients are man-made cannabinoid compounds. Synthetic cannabinoid users report some effects similar to those produced by marijuana: elevated mood relaxation altered perception symptoms of psychosis Synthetic cannabinoids can ...

  12. Fabrication of tubular tissue constructs by centrifugal casting of cells suspended in an in situ crosslinkable hyaluronan-gelatin hydrogel.

    Science.gov (United States)

    Mironov, Vladimir; Kasyanov, Vladimir; Zheng Shu, Xiao; Eisenberg, Carol; Eisenberg, Leonard; Gonda, Steve; Trusk, Thomas; Markwald, Roger R; Prestwich, Glenn D

    2005-12-01

    Achieving the optimal cell density and desired cell distribution in scaffolds is a major goal of cell seeding technologies in tissue engineering. In order to reach this goal, a novel centrifugal casting technology was developed using in situ crosslinkable hyaluronan-based (HA) synthetic extracellular matrix (sECM). Living cells were suspended in a viscous solution of thiol-modified HA and thiol-modified gelatin, a polyethyleneglycol diacrylate crosslinker was added, and a hydrogel was formed during rotation. The tubular tissue constructs consisting of a densely packed cell layer were fabricated with the rotation device operating at 2000 rpm for 10 min. The majority of cells suspended in the HA mixture before rotation were located inside the layer after centrifugal casting. Cells survived the effect of the centrifugal forces experienced under the rotational regime employed. The volume cell density (65.6%) approached the maximal possible volume density based on theoretical sphere packing models. Thus, centrifugal casting allows the fabrication of tubular constructs with the desired redistribution, composition and thickness of cell layers that makes the maximum efficient use of available cells. Centrifugal casting in this sECM would enable rapid fabrication of tissue-engineered vascular grafts, as well as other tubular and planar tissue-engineered constructs.

  13. Scaffold-Free Tubular Tissues Created by a Bio-3D Printer Undergo Remodeling and Endothelialization when Implanted in Rat Aortae.

    Science.gov (United States)

    Itoh, Manabu; Nakayama, Koichi; Noguchi, Ryo; Kamohara, Keiji; Furukawa, Kojirou; Uchihashi, Kazuyoshi; Toda, Shuji; Oyama, Jun-Ichi; Node, Koichi; Morita, Shigeki

    2015-01-01

    Small caliber vascular prostheses are not clinically available because synthetic vascular prostheses lack endothelial cells which modulate platelet activation, leukocyte adhesion, thrombosis, and the regulation of vasomotor tone by the production of vasoactive substances. We developed a novel method to create scaffold-free tubular tissue from multicellular spheroids (MCS) using a "Bio-3D printer"-based system. This system enables the creation of pre-designed three-dimensional structures using a computer controlled robotics system. With this system, we created a tubular structure and studied its biological features. Using a "Bio-3D printer," we made scaffold-free tubular tissues (inner diameter of 1.5 mm) from a total of 500 MCSs (2.5× 104 cells per one MCS) composed of human umbilical vein endothelial cells (40%), human aortic smooth muscle cells (10%), and normal human dermal fibroblasts (50%). The tubular tissues were cultured in a perfusion system and implanted into the abdominal aortas of F344 nude rats. We assessed the flow by ultrasonography and performed histological examinations on the second (n = 5) and fifth (n = 5) day after implantation. All grafts were patent and remodeling of the tubular tissues (enlargement of the lumen area and thinning of the wall) was observed. A layer of endothelial cells was confirmed five days after implantation. The scaffold-free tubular tissues made of MCS using a Bio-3D printer underwent remodeling and endothelialization. Further studies are warranted to elucidate the underlying mechanism of endothelialization and its function, as well as the long-term results.

  14. Scaffold-Free Tubular Tissues Created by a Bio-3D Printer Undergo Remodeling and Endothelialization when Implanted in Rat Aortae.

    Directory of Open Access Journals (Sweden)

    Manabu Itoh

    Full Text Available Small caliber vascular prostheses are not clinically available because synthetic vascular prostheses lack endothelial cells which modulate platelet activation, leukocyte adhesion, thrombosis, and the regulation of vasomotor tone by the production of vasoactive substances. We developed a novel method to create scaffold-free tubular tissue from multicellular spheroids (MCS using a "Bio-3D printer"-based system. This system enables the creation of pre-designed three-dimensional structures using a computer controlled robotics system. With this system, we created a tubular structure and studied its biological features.Using a "Bio-3D printer," we made scaffold-free tubular tissues (inner diameter of 1.5 mm from a total of 500 MCSs (2.5× 104 cells per one MCS composed of human umbilical vein endothelial cells (40%, human aortic smooth muscle cells (10%, and normal human dermal fibroblasts (50%. The tubular tissues were cultured in a perfusion system and implanted into the abdominal aortas of F344 nude rats. We assessed the flow by ultrasonography and performed histological examinations on the second (n = 5 and fifth (n = 5 day after implantation. All grafts were patent and remodeling of the tubular tissues (enlargement of the lumen area and thinning of the wall was observed. A layer of endothelial cells was confirmed five days after implantation.The scaffold-free tubular tissues made of MCS using a Bio-3D printer underwent remodeling and endothelialization. Further studies are warranted to elucidate the underlying mechanism of endothelialization and its function, as well as the long-term results.

  15. Urinary proteins of tubular origin: basic immunochemical and clinical aspects.

    Science.gov (United States)

    Scherberich, J E

    1990-01-01

    A variety of tubular marker proteins, as compared to healthy controls, are excreted at an increased rate in the urine of patients with renal damage. Beside cytoplasmic glutathione-S-transferase and lysosomal beta-N-acetyl-glucosaminidase (beta-NAG) the majority of kidney-related urine proteins derives from membrane surface components of the most vulnerable proximal tubule epithelia, among them ala-(leu-gly)-aminopeptidase, gamma-glutamyl transpeptidase (GGT), the tubular portion of angiotensinase A, the major brush border glycoprotein 'SGP-240' and adenosine-deaminase-binding protein. Urinary tissue proteins, e.g. brush border (BB) microvilli, are immunologically identical with those antigens prepared from cell membranes of the human kidney itself. BB antigens are shed into the urine of patients with glomerulonephritis, interstitial nephritis, systemic diseases, e.g. systemic lupus erythematosus (SLE), diabetes mellitus and multiple myeloma, arterial hypertension, infectious diseases (malaria, AIDS) and after operations, renal grafting and administration of X-ray contrast media, aminoglycosides or certain cytostatics (cis-platinum). Tissue proteinuria of tubular proteins is determined by enzyme-kinetic or quantitative immunological assays applying either poly- or monoclonal antikidney antibodies. Clinical, ultrastructural and histochemical studies support the idea that both 'soluble' and high-molecular-weight membrane particles (vacuolar blebs, greater than 10(6) dalton) as well as microfilamental components of the epithelial cytoskeleton contribute to tubular 'histuria' which appears as a sensitive parameter in monitoring tubular damage under clinical conditions at a very early phase.

  16. Proximal tubular dysfunction as an indicator of chronic graft dysfunction

    Directory of Open Access Journals (Sweden)

    N.O.S. Câmara

    2009-03-01

    Full Text Available New strategies are being devised to limit the impact of renal sclerosis on graft function. Individualization of immunosuppression, specifically the interruption of calcineurin-inhibitors has been tried in order to promote better graft survival once chronic graft dysfunction has been established. However, the long-term impact of these approaches is still not totally clear. Nevertheless, patients at higher risk for tubular atrophy and interstitial fibrosis (TA/IF development should be carefully monitored for tubular function as well as glomerular performance. Since tubular-interstitial impairment is an early event in TA/IF pathogenesis and associated with graft function, it seems reasonable that strategies directed at assessing tubular structural integrity and function would yield important functional and prognostic data. The measurement of small proteins in urine such as α-1-microglobulin, N-acetyl-beta-D-glucosaminidase, alpha/pi S-glutathione transferases, β-2 microglobulin, and retinol binding protein is associated with proximal tubular cell dysfunction. Therefore, its straightforward assessment could provide a powerful tool in patient monitoring and ongoing clinical assessment of graft function, ultimately helping to facilitate longer patient and graft survival associated with good graft function.

  17. The glomerulo-tubular junction: a target in renal diseases.

    Science.gov (United States)

    Lindop, G B M; Gibson, I W; Downie, T T; Vass, D; Cohen, E P

    2002-05-01

    Both global and segmental glomerulopathies may damage specific areas of the renal glomerulus. Diseases associated with glomerular hyperperfusion cause lesions at the vascular pole, while diseases associated with proteinuria often damage the tubular pole. Atubular glomeruli are now known to be plentiful in a variety of common renal diseases. These glomeruli are disconnected from their tubule at the tubular pole and therefore cannot participate in the production of urine. It is widely believed that the disconnection is a result of external compression by periglomerular fibrosis. However, the variable anatomy and cell populations within both the glomerulus and the beginning of the proximal tubule at the glomerulo-tubular junction may also have important roles to play in the response to damage at this sensitive site of the nephron.

  18. Klinefelter's syndrome with renal tubular acidosis: impact on height.

    Science.gov (United States)

    Jebasingh, F; Paul, T V; Spurgeon, R; Abraham, S; Jacob, J J

    2010-02-01

    A 19-year-old Indian man presented with a history of proximal muscle weakness, knock knees and gynaecomastia. On examination he had features of rickets and bilateral small testes. Karyotyping revealed a chromosomal pattern of 47,XXX, confirming the diagnosis of Klinefelter's syndrome. He was also found to have hyperchloraemic metabolic acidosis with hypokalaemia, hypophosphataemia, phosphaturia and glycosuria, which favoured a diagnosis of proximal renal tubular acidosis. Patients with Klinefelter's syndrome typically have a tall stature due to androgen deficiency, resulting in unfused epiphyses and an additional X chromosome. However, this patient had a short stature due to associated proximal renal tubular acidosis. To the best of our knowledge, this is the second case of Klinefelter's syndrome with short stature due to associated renal tubular acidosis reported in the literature. This report highlights the need to consider other causes when patients with Klinefelter's syndrome present with a short stature.

  19. Power generation characteristics of tubular type SOFC by wet process

    Energy Technology Data Exchange (ETDEWEB)

    Tajiri, H.; Nakayama, T. [Kyushu Electric Power Company, Inc., Fukuoka (Japan); Kuroishi, M. [TOTO Ltd., Kanagawa (Japan)] [and others

    1996-12-31

    The development of a practical solid oxide fuel cell requires improvement of a cell performance and a cell manufacturing technology suitable for the mass production. In particular tubular type SOFC is thought to be superior in its reliability because its configuration can avoid the high temperature sealing and reduce the thermal stress resulting from the contact between cells. The authors have fabricated a tubular cell with an air electrode support by a wet processing technique, which is suitable for mass production in improving a power density. To enhance the power output of the module, the Integrated Tubular-Type (ITT) cell has been developed. This paper reports the performance of the single cells with various active anode areas and the bundle with series-connected 9-ITT cells with an active anode area of 840 cm{sup 2}.

  20. Forecasting elections in Europe: Synthetic models

    OpenAIRE

    Michael S. Lewis-Beck; Ruth Dassonneville

    2015-01-01

    Scientific work on national election forecasting has become most developed for the United States case, where three dominant approaches can be identified: Structuralists, Aggregators, and Synthesizers. For European cases, election forecasting models remain almost exclusively Structuralist. Here we join together structural modeling and aggregate polling results, to form a hybrid, which we label a Synthetic Model. This model contains a political economy core, to which poll numbers are added (to ...

  1. RESEARCH ON HYDROFORMING TUBULAR PART WITH LARGE PERIMETER DIFFERENCE

    Institute of Scientific and Technical Information of China (English)

    X.S. Wang; S.J. Yuan; X.R. Huang; Y.X. Yao; Z.R. Wang

    2008-01-01

    The tube hydroforming process for manufacturing the tubular part with large perimeter difference was studied by means of experiments and FE simulation. It is an asymmetrical one and the expansion ratio is 70 percent. The part is successfully hydroformed by applying the useful wrinkles to accumulate suffcient metal in the area with large expansion ratio. The thickness distribution is analyzed, and the maximum thinning ratio of the part is 21.6 percent. It is shown from the experiment and simulation results that the tubular part with large perimeter difference, long expansion area and asymmetrical shape can be obtained in one step, applying the useful wrinkles. Typical failure modes were analyzed.

  2. Renal histology and immunopathology in distal renal tubular acidosis.

    Science.gov (United States)

    Feest, T G; Lockwood, C M; Morley, A R; Uff, J S

    1978-11-01

    Renal biospy studies are reported from 10 patients with distal renal tubular acidosis (DRTA). On the biopsies from 6 patients who had associated immunological abnormalities immunofluorescent studies for immunoglobulins, complement, and fibrin were performed. Interstitial cellular infiltration and fibrosis were common findings in patients with and without immunological abnormalities, and were usually associated with nephrocalcinosis and/or recurrent urinary infection. No immune deposits were demonstrated in association with the renal tubules. This study shows that DRTA in immunologically abnormal patients is not caused by tubular deposition of antibody or immune complexes. The possibility of cell mediated immune damage is discussed.

  3. The origin of tubular lava stalactites and other related forms

    Directory of Open Access Journals (Sweden)

    Kevin Allred

    1998-01-01

    Full Text Available Tubular lava stalactites are often found in lava tubes. Field observations, sample analysis, and comparative studies indicate that these are segregations extruded during cooling from partially crystallized lava al about 1,070 - 1,000 °C. Retrograde boiling (gas pressure within the lava provides a mechanism to expel the interstitial liquid. In addition to tubular lava stalactites, a variety of other lava features can also result, such as lava helictites, lava coralloids, barnacle-like stretched lava, runners, runner channels, and some lava blisters and squeeze-ups.

  4. [From synthetic biology to synthetic humankind].

    Science.gov (United States)

    Nouvel, Pascal

    2015-01-01

    In this paper, we propose an historical survey of the expression "synthetic biology" in order to identify its main philosophical components. The result of the analysis is then used to investigate the meaning of the notion of "synthetic man". It is shown that both notions share a common philosophical background that can be summed up by the short but meaningful assertion: "biology is technology". The analysis allows us to distinguish two notions that are often confused in transhumanist literature: the notion of synthetic man and the notion of renewed man. The consequences of this crucial distinction are discussed. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  5. 78 FR 41421 - Certain Oil Country Tubular Goods From India, Korea, Philippines, Saudi Arabia, Taiwan, Thailand...

    Science.gov (United States)

    2013-07-10

    ..., Philippines, Saudi Arabia, Taiwan, Thailand, Turkey, Ukraine, and Vietnam of certain oil country tubular goods... COMMISSION Certain Oil Country Tubular Goods From India, Korea, Philippines, Saudi Arabia, Taiwan, Thailand, Turkey, Ukraine, and Vietnam; Institution of Antidumping and Countervailing Duty Investigations...

  6. Modeling constrained sintering of bi-layered tubular structures

    DEFF Research Database (Denmark)

    Tadesse Molla, Tesfaye; Kothanda Ramachandran, Dhavanesan; Ni, De Wei;

    2015-01-01

    . Furthermore, the model is validated using densification results from sintering of bi-layered tubular ceramic oxygen membrane based on porous MgO and Ce0.9Gd0.1O1.95-d layers. Model input parameters, such as the shrinkage kinetics and viscous parameters are obtained experimentally using optical dilatometry...

  7. Tubularized incised plate technique for recurrent hypospadias: a ...

    African Journals Online (AJOL)

    primary techniques are unsatisfactory. ... TIP urethroplasty in the management of recurrent ... was used for quantitative data. .... erection and the risk of infection, especially in patients .... currently considered the best tool for complicated .... 10 Mustafa M. The concept of tubularized incised plate hypospadias repair for different ...

  8. Changes at the glomerulo-tubular junction in renal transplants.

    Science.gov (United States)

    Lee, S J; Howie, A J

    1988-12-01

    We studied by microscopy 377 biopsies, nephrectomies, and necropsy kidneys from 123 human renal transplants. We discovered two common abnormalities of the renal corpuscle, both affecting the glomerulo-tubular junction. Adhesion of the tip of the glomerular tuft to the origin of the tubule, as reported in various non-transplant glomerulopathies, was seen in 197 specimens (52 per cent). This change was common in material showing acute or chronic vascular rejection and glomerulopathy, and was almost universal in transplants that had been in place for over 1 year. Another change at the glomerulo-tubular junction, not previously highlighted, consisted of an infiltrate of lymphocytes or neutrophil polymorphs into the epithelium at the tubular origin. This change was seen in 145 specimens (38 per cent) and was associated with cellular rejection and ascending infection. These changes are of importance because they show two responses of the kidney to injury that involve the glomerulo-tubular junction and thus suggest that this part of the kidney has some specific properties that have been largely neglected up to now.

  9. Distal renal tubular acidosis with multiorgan autoimmunity: A case report

    NARCIS (Netherlands)

    M.J. Van Den Wildenberg (Maria J.); E.J. Hoorn (Ewout); N. Mohebbi (Nilufar); C.A. Wagner (Carsten); A.J.J. Woittiez; P.A.M. de Vries; P. Laverman (Peter)

    2015-01-01

    textabstractA 61-year-old woman with a history of pernicious anemia presented with progressive muscle weakness and dysarthria. Hypokalemic paralysis (serum potassium, 1.4 mEq/L) due to distal renal tubular acidosis (dRTA) was diagnosed. After excluding several possible causes, dRTA was considered au

  10. Renal pathophysiologic role of cortical tubular inclusion bodies.

    Science.gov (United States)

    Radi, Zaher A; Stewart, Zachary S; Grzemski, Felicity A; Bobrowski, Walter F

    2013-01-01

    Renal tubular inclusion bodies are rarely associated with drug administration. The authors describe the finding of renal cortical tubular intranuclear and intracytoplasmic inclusion bodies associated with the oral administration of a norepinephrine/serotonin reuptake inhibitor (NSRI) test article in Sprague-Dawley (SD) rats. Rats were given an NSRI daily for 4 weeks, and kidney histopathologic, ultrastructural pathology, and immunohistochemical examinations were performed. Round eosinophilic intranuclear inclusion bodies were observed histologically in the tubular epithelial cells of the renal cortex in male and female SD rats given the NSRI compound. No evidence of degeneration or necrosis was noted in the inclusion-containing renal cells. By ultrastructural pathology, inclusion bodies consisted of finely granular, amorphous, and uniformly stained nonmembrane-bound material. By immunohistochemistry, inclusion bodies stained positive for d-amino acid oxidase (DAO) protein. In addition, similar inclusion bodies were noted in the cytoplasmic tubular epithelial compartment by ultrastructural and immunohistochemical examination.  This is the first description of these renal inclusion bodies after an NSRI test article administration in SD rats. Such drug-induced renal inclusion bodies are rat-specific, do not represent an expression of nephrotoxicity, represent altered metabolism of d-amino acids, and are not relevant to human safety risk assessment.

  11. Urinary Markers of Tubular Injury in Early Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Temesgen Fiseha

    2016-01-01

    Full Text Available Diabetic nephropathy (DN is a common and serious complication of diabetes associated with adverse outcomes of renal failure, cardiovascular disease, and premature mortality. Early and accurate identification of DN is therefore of critical importance to improve patient outcomes. Albuminuria, a marker of glomerular involvement in early renal damage, cannot always detect early DN. Thus, more sensitive and specific markers in addition to albuminuria are needed to predict the early onset and progression of DN. Tubular injury, as shown by the detection of tubular injury markers in the urine, is a critical component of the early course of DN. These urinary tubular markers may increase in diabetic patients, even before diagnosis of microalbuminuria representing early markers of normoalbuminuric DN. In this review we summarized some new and important urinary markers of tubular injury, such as neutrophil gelatinase associated lipocalin (NGAL, kidney injury molecule-1 (KIM-1, liver-type fatty acid binding protein (L-FABP, N-acetyl-beta-glucosaminidase (NAG, alpha-1 microglobulin (A1M, beta 2-microglobulin (B2-M, and retinol binding protein (RBP associated with early DN.

  12. Tubular aggregate myopathy: A phenotypic spectrum and morphological study

    Directory of Open Access Journals (Sweden)

    Ghosh Amrita

    2010-12-01

    Full Text Available Tubular aggregates (TAs are inclusions described in skeletal muscle in a variety of disorders. In a retrospective analysis, TAs were found in 18 (0.24% cases and involved a spectrum of clinical phenotypes. Ultrastructurally, four distinct types of aggregates were noted. There was no correlation between the clinical phenotypes, duration of illness and types of TAs.

  13. Cystinosis (ctns) zebrafish mutant shows pronephric glomerular and tubular dysfunction

    Science.gov (United States)

    Elmonem, Mohamed A.; Khalil, Ramzi; Khodaparast, Ladan; Khodaparast, Laleh; Arcolino, Fanny O.; Morgan, Joseph; Pastore, Anna; Tylzanowski, Przemko; Ny, Annelii; Lowe, Martin; de Witte, Peter A.; Baelde, Hans J.; van den Heuvel, Lambertus P.; Levtchenko, Elena

    2017-01-01

    The human ubiquitous protein cystinosin is responsible for transporting the disulphide amino acid cystine from the lysosomal compartment into the cytosol. In humans, Pathogenic mutations of CTNS lead to defective cystinosin function, intralysosomal cystine accumulation and the development of cystinosis. Kidneys are initially affected with generalized proximal tubular dysfunction (renal Fanconi syndrome), then the disease rapidly affects glomeruli and progresses towards end stage renal failure and multiple organ dysfunction. Animal models of cystinosis are limited, with only a Ctns knockout mouse reported, showing cystine accumulation and late signs of tubular dysfunction but lacking the glomerular phenotype. We established and characterized a mutant zebrafish model with a homozygous nonsense mutation (c.706 C > T; p.Q236X) in exon 8 of ctns. Cystinotic mutant larvae showed cystine accumulation, delayed development, and signs of pronephric glomerular and tubular dysfunction mimicking the early phenotype of human cystinotic patients. Furthermore, cystinotic larvae showed a significantly increased rate of apoptosis that could be ameliorated with cysteamine, the human cystine depleting therapy. Our data demonstrate that, ctns gene is essential for zebrafish pronephric podocyte and proximal tubular function and that the ctns-mutant can be used for studying the disease pathogenic mechanisms and for testing novel therapies for cystinosis. PMID:28198397

  14. Intrarenal purinergic signaling in the control of renal tubular transport

    DEFF Research Database (Denmark)

    Prætorius, Helle; Leipziger, Jens Georg

    2010-01-01

    Renal tubular epithelial cells receive hormonal input that regulates volume and electrolyte homeostasis. In addition, numerous intrarenal, local signaling agonists have appeared on the stage of renal physiology. One such system is that of intrarenal purinergic signaling. This system involves all ...

  15. Urinary Markers of Tubular Injury in Early Diabetic Nephropathy

    Science.gov (United States)

    Fiseha, Temesgen; Tamir, Zemenu

    2016-01-01

    Diabetic nephropathy (DN) is a common and serious complication of diabetes associated with adverse outcomes of renal failure, cardiovascular disease, and premature mortality. Early and accurate identification of DN is therefore of critical importance to improve patient outcomes. Albuminuria, a marker of glomerular involvement in early renal damage, cannot always detect early DN. Thus, more sensitive and specific markers in addition to albuminuria are needed to predict the early onset and progression of DN. Tubular injury, as shown by the detection of tubular injury markers in the urine, is a critical component of the early course of DN. These urinary tubular markers may increase in diabetic patients, even before diagnosis of microalbuminuria representing early markers of normoalbuminuric DN. In this review we summarized some new and important urinary markers of tubular injury, such as neutrophil gelatinase associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), liver-type fatty acid binding protein (L-FABP), N-acetyl-beta-glucosaminidase (NAG), alpha-1 microglobulin (A1M), beta 2-microglobulin (B2-M), and retinol binding protein (RBP) associated with early DN. PMID:27293888

  16. Subanalytic Bundles and Tubular Neighbourhoods of Zero-Loci

    Indian Academy of Sciences (India)

    Vishwambhar Pati

    2003-08-01

    We introduce the natural and fairly general notion of a subanalytic bundle (with a finite dimensional vector space of sections) on a subanalytic subset of a real analytic manifold , and prove that when is compact, there is a Baire subset of sections in whose zero-loci in have tubular neighbourhoods, homeomorphic to the restriction of the given bundle to these zero-loci.

  17. Glutamatergic signaling maintains the epithelial phenotype of proximal tubular cells

    NARCIS (Netherlands)

    Bozic, M.; de Rooij, J.; Parisi, E.; Ortega, M.R.; Fernandez, E.; Valdivielso, J.M.

    2011-01-01

    Epithelial-mesenchymal transition (EMT) contributes to the progression of renal tubulointerstitial fibrosis. The N-methyl-d-aspartate receptor (NMDAR), which is present in proximal tubular epithelium, is a glutamate receptor that acts as a calcium channel. Activation of NMDAR induces actin rearrange

  18. Renal tubular leakage complicating microcephalic osteodysplastic primordial dwarfism.

    Science.gov (United States)

    Eason, J; Hall, C M; Trounce, J Q

    1995-01-01

    We describe a male infant with phenotypic and radiological features of microcephalic osteodysplastic primordial dwarfism type I/III. He showed severe osteoporosis and biochemical derangement owing to renal tubular leakage, which has not previously been reported in this condition. He died aged 5 months. Images PMID:7783178

  19. Screening renal stone formers for distal renal tubular acidosis

    DEFF Research Database (Denmark)

    Osther, P J; Hansen, A B; Røhl, H F

    1989-01-01

    A group of 110 consecutive renal stone formers were screened for distal renal tubular acidosis (RTA) using morning fasting urinary pH (mfUpH) levels followed by a short ammonium chloride loading test in patients with levels above 6.0. In 14 patients (12.7%) a renal acidification defect was noted...

  20. Geochemical characterization of tubular alteration features in subseafloor basalt glass

    Science.gov (United States)

    Knowles, Emily; Staudigel, Hubert; Templeton, Alexis

    2013-07-01

    There are numerous indications that subseafloor basalts may currently host a huge quantity of active microbial cells and contain biosignatures of ancient life in the form of physical and chemical basalt glass alteration. Unfortunately, technological challenges prevent us from observing the formation and mineralization of these alteration features in situ, or reproducing tubular basalt alteration processes in the laboratory. Therefore, comprehensive analysis of the physical and chemical traces retained in mineralized tubules is currently the best approach for deciphering a record of glass alteration. We have used a number of high-resolution spectroscopic and microscopic methods to probe the geochemical and mineralogical characteristics of tubular alteration features in basalt glasses obtained from a suite of subseafloor drill cores that covers a range of different collection locations and ages. By combining three different synchrotron-based X-ray measurements - X-ray fluorescence microprobe mapping, XANES spectroscopy, and μ-XRD - with focused ion beam milling and transmission electron microscopy, we have spatially resolved the major and trace element distributions, as well as the oxidation state of Fe, determined the coordination chemistry of Fe, Mn and Ti at the micron-scale, and constrained the secondary minerals within these features. The tubular alteration features are characterized by strong losses of Fe2+, Mn2+, and Ca2+ compared to fresh glass, oxidation of the residual Fe, and the accumulation of Ti and Cu. The predominant phases infilling the alteration regions are Fe3+-bearing silicates dominated by 2:1 clays, with secondary Fe- and Ti-oxides, and a partially oxidized Mn-silicate phase. These geochemical patterns observed within the tubular alteration features are comparable across a diverse suite of samples formed over the past 5-100 Ma, which shows that the microscale mineralization processes are common and consistent throughout the ocean basins and

  1. 78 FR 52213 - Certain Oil Country Tubular Goods From India, Korea, the Philippines, Saudi Arabia, Taiwan...

    Science.gov (United States)

    2013-08-22

    ... tubular goods from India and Turkey and LTFV imports of certain oil country tubular goods from India... COMMISSION Certain Oil Country Tubular Goods From India, Korea, the Philippines, Saudi Arabia, Taiwan, Thailand, Turkey, Ukraine, and Vietnam: Determinations On the basis of the record \\1\\ developed in...

  2. Factor H and Properdin Recognize Different Epitopes on Renal Tubular Epithelial Heparan Sulfate

    NARCIS (Netherlands)

    Zaferani, Azadeh; Vives, Romain R.; van der Pol, Pieter; Navis, Gerjan J.; Daha, Mohamed R.; van Kooten, Cees; Lortat-Jacob, Hugues; Seelen, Marc A.; van den Born, Jacob

    2012-01-01

    During proteinuria, renal tubular epithelial cells become exposed to ultrafiltrate-derived serum proteins, including complement factors. Recently, we showed that properdin binds to tubular heparan sulfates (HS). We now document that factor H also binds to tubular HS, although to a different epitope

  3. Factor H and Properdin Recognize Different Epitopes on Renal Tubular Epithelial Heparan Sulfate

    NARCIS (Netherlands)

    Zaferani, Azadeh; Vives, Romain R.; van der Pol, Pieter; Navis, Gerjan J.; Daha, Mohamed R.; van Kooten, Cees; Lortat-Jacob, Hugues; Seelen, Marc A.; van den Born, Jacob

    2012-01-01

    During proteinuria, renal tubular epithelial cells become exposed to ultrafiltrate-derived serum proteins, including complement factors. Recently, we showed that properdin binds to tubular heparan sulfates (HS). We now document that factor H also binds to tubular HS, although to a different epitope

  4. Lateral diffusion on tubular membranes: quantification of measurements bias.

    Directory of Open Access Journals (Sweden)

    Marianne Renner

    Full Text Available Single Particle Tracking (SPT is a powerful technique for the analysis of the lateral diffusion of the lipid and protein components of biological membranes. In neurons, SPT allows the study of the real-time dynamics of receptors for neurotransmitters that diffuse continuously in and out synapses. In the simplest case where the membrane is flat and is parallel to the focal plane of the microscope the analysis of diffusion from SPT data is relatively straightforward. However, in most biological samples the membranes are curved, which complicates analysis and may lead to erroneous conclusions as for the mode of lateral diffusion. Here we considered the case of lateral diffusion in tubular membranes, such as axons, dendrites or the neck of dendritic spines. Monte Carlo simulations allowed us to evaluate the error in diffusion coefficient (D calculation if the curvature is not taken into account. The underestimation is determined by the diameter of the tubular surface, the frequency of image acquisition and the degree of mobility itself. We found that projected trajectories give estimates that are 25 to 50% lower than the real D in case of 2D-SPT over the tubular surface. The use of 3D-SPT improved the measurements if the frequency of image acquisition was fast enough in relation to the mobility of the molecules and the diameter of the tube. Nevertheless, the calculation of D from the components of displacements in the axis of the tubular structure gave accurate estimate of D, free of geometrical artefacts. We show the application of this approach to analyze the diffusion of a lipid on model tubular membranes and of a membrane-bound GFP on neurites from cultured rat hippocampal neurons.

  5. Lateral diffusion on tubular membranes: quantification of measurements bias.

    Science.gov (United States)

    Renner, Marianne; Domanov, Yegor; Sandrin, Fanny; Izeddin, Ignacio; Bassereau, Patricia; Triller, Antoine

    2011-01-01

    Single Particle Tracking (SPT) is a powerful technique for the analysis of the lateral diffusion of the lipid and protein components of biological membranes. In neurons, SPT allows the study of the real-time dynamics of receptors for neurotransmitters that diffuse continuously in and out synapses. In the simplest case where the membrane is flat and is parallel to the focal plane of the microscope the analysis of diffusion from SPT data is relatively straightforward. However, in most biological samples the membranes are curved, which complicates analysis and may lead to erroneous conclusions as for the mode of lateral diffusion. Here we considered the case of lateral diffusion in tubular membranes, such as axons, dendrites or the neck of dendritic spines. Monte Carlo simulations allowed us to evaluate the error in diffusion coefficient (D) calculation if the curvature is not taken into account. The underestimation is determined by the diameter of the tubular surface, the frequency of image acquisition and the degree of mobility itself. We found that projected trajectories give estimates that are 25 to 50% lower than the real D in case of 2D-SPT over the tubular surface. The use of 3D-SPT improved the measurements if the frequency of image acquisition was fast enough in relation to the mobility of the molecules and the diameter of the tube. Nevertheless, the calculation of D from the components of displacements in the axis of the tubular structure gave accurate estimate of D, free of geometrical artefacts. We show the application of this approach to analyze the diffusion of a lipid on model tubular membranes and of a membrane-bound GFP on neurites from cultured rat hippocampal neurons.

  6. sup 99m Tc renal tubular function agents: Current status

    Energy Technology Data Exchange (ETDEWEB)

    Eshima, D.; Fritzberg, A.R.; Taylor, A. Jr. (Emory Univ. School of Medicine, Atlanta, GA (USA))

    1990-01-01

    Orthoiodohippuric (OIH) acid labeled with 131I is a widely used renal radiopharmaceutical agent and has been the standard radiopharmaceutical agent for the measurement of effective renal plasma flow (EPRF). Limitations to the routine clinical use of 131I OIH are related to the suboptimal imaging properties of the 131I radionuclide and its relatively high radiation dose. 123I has been substituted for 131I; however, its high cost and short shelf-life have limited its widespread use. Recent work has centered on the development of a new 99mTc renal tubular function agent, which would use the optimal radionuclidic properties and availability of 99mTc and combine the clinical information provided by OIH. The search for a suitable 99mTc renal tubular function agent has focused on the diamide dithiolate (N2S2), the paraaminohippuric iminodiacetic acid (PAHIDA), and the triamide mercaptide (N3S) donor ligand systems. To date, the most promising 99mTc tubular function agent is the N3S complex: 99mTc mercaptoacetyltriglycine (99mTc MAG3). Studies in animal models in diuresis, dehydration, acid or base imbalance, ischemia, and renal artery stenosis demonstrate that 99mTc MAG3 behaves similarly to 131I OIH. A simple kit formulation is available that yields the 99mTc MAG3 complex in high radiochemical purity. Studies in normal subjects and patients indicate that 99mTc MAG3 is an excellent 99mTc renal tubular agent, but its plasma clearance is only 50% to 60% that of OIH. In an effort to develop an improved 99mTc renal tubular function agent, changes have been made in the core N3S donor ligand system, but to date no agent has been synthesized that is clinically superior to 99mTc MAG3. 61 references.

  7. Renal tubular function in children with beta-thalassemia minor.

    Science.gov (United States)

    Kalman, Süleyman; Atay, A Avni; Sakallioglu, Onur; Ozgürtaş, Taner; Gök, Faysal; Kurt, Ismail; Kürekçi, A Emin; Ozcan, Okan; Gökçay, Erdal

    2005-10-01

    beta-thalassemia minor is a common heterozygous haemoglobinopathy that is characterized by both microcytosis and hypochromia. It requires no treatment. It has been postulated that low-grade haemolysis, tubular iron deposition and toxins derived from erythrocytes might cause renal tubular damage in adult patients with beta-thalassemia minor. Our aim was to investigate the renal tubular functions in children with beta-thalassemia minor and to determine its possible harmful effects. The study was conducted on 32 children (14 female and 18 male) at the age of 5.8 +/- 3.1 years (range 2-14 years) with beta-thalassemia minor. The patients were classified as anaemic (haemoglobin (Hb) 11 g/dL) (Group 2, n = 18). A control group was formed with 18 healthy children whose ages and sexes match those in other groups (Group 3, n = 18). Fractional excretion of sodium (FE(Na), %), fractional excretion of magnesium (FE(Mg), %), fractional excretion of uric acid (FE(UA), %) and tubular phosphorus reabsorption (TPR,%) were calculated with standard formulas. Urinary calcium excretion (mg/kg per 24 h), zinc (Zn) (microg/dL), glucosuria (mg/dL), beta-2 microglobulin (mg/dL) and N-acetyl-beta-D-glycosaminidase (NAG, U/mmol creatinine) levels were measured through biochemical methods. There was no statistically significant difference among the three groups in terms of the results of FE(Na) (%), FE(Mg) (%), FE(UA) (%), TPR (%), calciuria (mg/kg per 24 h), NAG, urine Zn, proteinuria, glucosuria or urine beta- 2 microglobulin levels (P > 0.05). On the contrary of children with beta-thalassemia major, renal tubular dysfunction has not been determined in children with beta-thalassemia minor in the present study.

  8. Designing synthetic biology.

    Science.gov (United States)

    Agapakis, Christina M

    2014-03-21

    Synthetic biology is frequently defined as the application of engineering design principles to biology. Such principles are intended to streamline the practice of biological engineering, to shorten the time required to design, build, and test synthetic gene networks. This streamlining of iterative design cycles can facilitate the future construction of biological systems for a range of applications in the production of fuels, foods, materials, and medicines. The promise of these potential applications as well as the emphasis on design has prompted critical reflection on synthetic biology from design theorists and practicing designers from many fields, who can bring valuable perspectives to the discipline. While interdisciplinary connections between biologists and engineers have built synthetic biology via the science and the technology of biology, interdisciplinary collaboration with artists, designers, and social theorists can provide insight on the connections between technology and society. Such collaborations can open up new avenues and new principles for research and design, as well as shed new light on the challenging context-dependence-both biological and social-that face living technologies at many scales. This review is inspired by the session titled "Design and Synthetic Biology: Connecting People and Technology" at Synthetic Biology 6.0 and covers a range of literature on design practice in synthetic biology and beyond. Critical engagement with how design is used to shape the discipline opens up new possibilities for how we might design the future of synthetic biology.

  9. Hybrid Baryons

    CERN Document Server

    Page, P R

    2003-01-01

    We review the status of hybrid baryons. The only known way to study hybrids rigorously is via excited adiabatic potentials. Hybrids can be modelled by both the bag and flux-tube models. The low-lying hybrid baryon is N 1/2^+ with a mass of 1.5-1.8 GeV. Hybrid baryons can be produced in the glue-rich processes of diffractive gamma N and pi N production, Psi decays and p pbar annihilation.

  10. Tenofovir is associated with increased tubular proteinuria and asymptomatic renal tubular dysfunction in Ghana.

    Science.gov (United States)

    Chadwick, David R; Sarfo, Fred S; Kirk, Elaine S M; Owusu, Dorcas; Bedu-Addo, George; Parris, Victoria; Owusu, Ann Lorraine; Phillips, Richard

    2015-12-01

    HIV infection is associated with increased risk of renal dysfunction, including tubular dysfunction (TD) related to antiretroviral therapy (ART). Tenofovir disoproxil fumarate (TDF) is becoming available for ART in sub-Saharan Africa, although data on its long-term safety there is limited. We aimed to study the prevalence of HIV-associated renal dysfunction in Ghana and explore associations between proteinuria or TD and potential risk factors, including TDF use. A single-centre cross-sectional observational study of patients taking ART was undertaken. Creatinine clearance (CrCl) was calculated and proteinuria detected with dipsticks. Spot urinary albumin and protein:creatinine ratios (uACR/uPCR) were measured and further evidence of TD (defined as having two or more characteristic features) sought. Logistic regression analysis identified factors associated with proteinuria or TD. In 330 patients, of whom 101 were taking TDF (median 20 months), the prevalence of CrCl proteinuria and TD was 7 %, 37 % and 15 %. Factors associated with proteinuria were baseline CD4-count [aOR 0.86/100 cell increment (95 % CI, 0.74-0.99)] and TDF use [aOR 2.74 (95 % CI, 1.38-5.43)]. The only factor associated with TD was TDF use [aOR 3.43 (95 % CI, 1.10-10.69)]. In a subset with uPCR measurements, uPCRs were significantly higher in patients taking TDF than those on other drugs (10.8 vs. 5.7 mg/mmol, p proteinuria and TD are common and associated with TDF use in Ghana. Further longitudinal studies to determine whether proteinuria, TD or TDF use are linked to progressive decline in renal function or other adverse outcomes are needed in Africa.

  11. Synthetic cathinone abuse

    Directory of Open Access Journals (Sweden)

    Capriola M

    2013-07-01

    Full Text Available Michael Capriola Thomasville Medical Center, Thomasville, NC, USA Abstract: The abuse of synthetic cathinones, widely known as bath salts, has been increasing since the mid-2000s. These substances are derivatives of the naturally occurring compound cathinone, which is the primary psychoactive component of khat. The toxicity of synthetic cathinones includes significant sympathomimetic effects, as well as psychosis, agitation, aggression, and sometimes violent and bizarre behavior. Mephedrone and methylenedioxypyrovalerone are currently the predominantly abused synthetic cathinones. Keywords: designer drugs/chemistry, street drugs/pharmacology, substance-related disorders/epidemiology, alkaloids/poisoning

  12. Synthetic Base Fluids

    Science.gov (United States)

    Brown, M.; Fotheringham, J. D.; Hoyes, T. J.; Mortier, R. M.; Orszulik, S. T.; Randles, S. J.; Stroud, P. M.

    The chemical nature and technology of the main synthetic lubricant base fluids is described, covering polyalphaolefins, alkylated aromatics, gas-to-liquid (GTL) base fluids, polybutenes, aliphatic diesters, polyolesters, polyalkylene glycols or PAGs and phosphate esters.Other synthetic lubricant base oils such as the silicones, borate esters, perfluoroethers and polyphenylene ethers are considered to have restricted applications due to either high cost or performance limitations and are not considered here.Each of the main synthetic base fluids is described for their chemical and physical properties, manufacture and production, their chemistry, key properties, applications and their implications when used in the environment.

  13. An early Cambrian agglutinated tubular lophophorate with brachiopod characters

    Science.gov (United States)

    Zhang, Z.-F.; Li, G.-X.; Holmer, L. E.; Brock, G. A.; Balthasar, U.; Skovsted, C. B.; Fu, D.-J.; Zhang, X.-L.; Wang, H.-Z.; Butler, A.; Zhang, Z.-L.; Cao, C.-Q.; Han, J.; Liu, J.-N.; Shu, D.-G.

    2014-05-01

    The morphological disparity of lophotrochozoan phyla makes it difficult to predict the morphology of the last common ancestor. Only fossils of stem groups can help discover the morphological transitions that occurred along the roots of these phyla. Here, we describe a tubular fossil Yuganotheca elegans gen. et sp. nov. from the Cambrian (Stage 3) Chengjiang Lagerstätte (Yunnan, China) that exhibits an unusual combination of phoronid, brachiopod and tommotiid (Cambrian problematica) characters, notably a pair of agglutinated valves, enclosing a horseshoe-shaped lophophore, supported by a lower bipartite tubular attachment structure with a long pedicle with coelomic space. The terminal bulb of the pedicle provided anchorage in soft sediment. The discovery has important implications for the early evolution of lophotrochozoans, suggesting rooting of brachiopods into the sessile lophotrochozoans and the origination of their bivalved bauplan preceding the biomineralization of shell valves in crown brachiopods.

  14. Dynamic model of microalgal production in tubular photobioreactors.

    Science.gov (United States)

    Fernández, I; Acién, F G; Fernández, J M; Guzmán, J L; Magán, J J; Berenguel, M

    2012-12-01

    A dynamic model for microalgal culture is presented. The model takes into account the fluid-dynamic and mass transfer, in addition to biological phenomena, it being based on fundamental principles. The model has been calibrated and validated using data from a pilot-scale tubular photobioreactor but it can be extended to other designs. It can be used to determine, from experimental measurements, the values of characteristic parameters. The model also allows a simulation of the system's dynamic behaviour in response to solar radiation, making it a useful tool for design and operation optimization of photobioreactors. Moreover, the model permits the identification of local pH gradients, dissolved oxygen and dissolved carbon dioxide; that can damage microalgae growth. In addition, the developed model can map the different characteristic time scales of phenomena inside microalgae cultures within tubular photobioreactors, meaning it is a valuable tool in the development of advanced control strategies for microalgae cultures.

  15. Mechanical reliability of geometrically imperfect tubular oxygen transport membranes

    DEFF Research Database (Denmark)

    Kwok, Kawai; Frandsen, Henrik Lund; Søgaard, Martin

    2014-01-01

    operation. This paper investigates numerically the failure risk of tubular oxygen transport membranes under industrial operating conditions using finite element modeling and Weibull strength analysis. The effects of component manufacturing defects on fracture probability are elucidated by explicit modeling...... of imperfections in the tubular membrane geometry. A supported membrane made of dense and porous Zr-doped-BSCF is studied as an illustrative example. It is shown that stresses induced by oxygen stoichiometry gradients relax over time due to creep and external pressure is the dominating source of stress in the long...... term. Therefore, creep has no adverse effect for geometrically perfect membranes. For geometrically imperfect membranes, curl and eccentricity are found to have insignificant influence on fracture risk while ovality is identified as the most critical geometric imperfection. Under the influence...

  16. A distal renal tubular acidosis showing hyperammonemia and hyperlactacidemia

    Directory of Open Access Journals (Sweden)

    C. Ripoli

    2012-08-01

    Full Text Available Introduction: distal renal tubular acidosis (dRTA presents itself with variable clinical manifestations and often with late expressions that impact on prognosis. Case report: A 45-day-old male infant was admitted with stopping growth, difficult feeding and vomiting after meals. Clinical tests and labs revealed a type 1 renal tubular acidosis, even if the first blood tests showed ammonium and lactate increase. We had to exclude metabolic diseases before having a certain diagnosis. Conclusions: blood and urine investigations and genetic tests are fundamental to formulate dRTA diagnosis and to plan follow-up, according to possible phenotypic expressions of recessive and dominant autosomal forms in patients with dRTA.

  17. Inner-tubular physicochemical processes of carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    YANG Quanhong; LI Lixiang; CHENG Huiming; WANG Maozhang; BAI Jinbo

    2003-01-01

    Nanosized inner cavities of carbon nanotubes (CNTs) afford quasi-one-dimensional (1D) confined space, in which materials adsorbed or filled are of reactivity greatly different from the materials adsorbed on a planar surface and quite a number of curious physicochemical processes will possibly occur. In other words, 1D CNT nanochannels may serve as "nanosized test tubes". In this article, on the basis of the unique chemical and physical properties of CNTs, the latest progresses of the research on peculiar inner-tubular physicochemical processes of CNTs are briefly reviewed from several aspects. The extraordinary 1D adsorption, capillary filling and nanoscale-confined reaction are discussed in detail. Moreover, the characteristics of "nanosized test tubes" are summarized and many unfamiliar inner cavity chemical processes are expected. Finally, the future direction and challenges on basic researches and potential applications of inner-tubular chemistry of CNTs are discussed.

  18. Acute tubular necrosis in a patient with paroxysmal nocturnal hemoglobinuria

    Directory of Open Access Journals (Sweden)

    Eranga S Wijewickrama

    2013-01-01

    Full Text Available Acute renal failure (ARF is a well-recognized complication of paroxysmal nocturnal hemoglobinuria (PNH. The predominant mechanism is intravascular hemolysis resulting in massive hemoglobinuria ARF. We report a case of acute tubular necrosis (ATN developed in the absence of overwhelming evidence of intravascular hemolysis in a 21-year-old man with anemia, who was eventually diagnosed to have PNH. The patient presented with rapidly deteriorating renal functions in the background of iron deficiency anemia, which was attributed to reflux esophagitis. There was no clinical or laboratory evidence of intravascular hemolysis. Renal biopsy revealed ATN with deposition of hemosiderin in the proximal tubular epithelial cells. Diagnosis of PNH was confirmed with a positive Ham′s test and flow cytometry. Our case emphasizes the need to consider ATN as a possible cause for ARF in patients suspected to have PNH even in the absence of overwhelming evidence of intravascular hemolysis.

  19. A Long Term Test of Differently Designed Evacuated Tubular Collectors

    DEFF Research Database (Denmark)

    Fan, Jianhua; Dragsted, Janne; Furbo, Simon

    2008-01-01

    carried out with different mean solar collector fluid temperatures and in different seasons of the year. The results of the measurements are presented in this paper. The influence of the mean solar collector fluid temperature on the thermal performance of the different collector designs will be discussed......During three years seven differently designed evacuated tubular collectors (ETCs) utilizing solar radiation from all directions have been investigated experimentally. The evacuated tubular solar collectors investigated include one SLL all-glass ETC from Tshinghua Solar Co. Ltd, four heat pipe ETCs...... of the inlet fluid to the collectors have been the same for all collectors. The volume flow rate through each of the collectors is adjusted so that the mean solar collector fluid temperature has been the same for all collectors. Thus a direct performance comparison is possible. The side-by-side tests were...

  20. Understanding shape and morphology of unusual tubular starch nanocrystals.

    Science.gov (United States)

    Gong, Bei; Liu, Wenxia; Tan, Hua; Yu, Dehai; Song, Zhaoping; Lucia, Lucian A

    2016-10-20

    Starch nanocrystals (SNC) are aptly described as the insoluble degradation byproducts of starch granules that purportedly display morphologies that are platelet-like, round, square, and oval-like. In this work, we reported the preparation of SNC with unprecedented tubular structures through sulfuric acid hydrolysis of normal maize starch, subsequent exposure to ammonia and relaxation at 4°C. High-resolution transmission electron microscopy observation clearly proved that the SNCs possess tubular nanostructures with polygonal cross-section. After further reviewing the transformations of SNC by acid hydrolysis, ammonia treatment, and curing time at 4°C, a mechanism for T-SNC formation is suggested. It is conjectured that T-SNC gradually self-assembles by combination of smaller platelet-like/square nanocrystals likely loosely aggregated by starch molecular chains from residual amorphous regions. This work paves the way for the pursuit of new approaches for the preparation of starch-based nanomaterials possessing unique morphologies.

  1. Segmental tubular sodium reabsorption in type 1 diabetes

    DEFF Research Database (Denmark)

    Dieperink, H; Eshøj, O; Leyssac, P P

    1993-01-01

    Segmental tubular sodium reabsorption in Type 1 (insulin-dependent) diabetes was measured in 36 patients in a cross-sectional study including one group (n = 13) without significant albuminuria (UalbV 1), one group (n = 16) with albuminuria in the range from 30 to 300 mg 24 h-1......, and a group (n = 7) with nephropathy (UalbV > 300 mg 24 h-1). Lithium clearance was used to measure end proximal delivery. From end proximal delivery, 51Cr-EDTA clearance (GFR) and sodium clearance, segmental tubular reabsorption was calculated. For all patients, GFR was directly correlated with end proximal...... delivery (r = 0.62, p 1, the direct correlation between GFR and end proximal delivery was also significant (r = 0.77, p

  2. Analysis of Synthetic Polymers.

    Science.gov (United States)

    Smith, Charles G.; And Others

    1989-01-01

    Reviews techniques for the characterization and analysis of synthetic polymers, copolymers, and blends. Includes techniques for structure determination, separation, and quantitation of additives and residual monomers; determination of molecular weight; and the study of thermal properties including degradation mechanisms. (MVL)

  3. Tissue cell assisted fabrication of tubular catalytic platinum microengines

    Science.gov (United States)

    Wang, Hong; Moo, James Guo Sheng; Pumera, Martin

    2014-09-01

    We report a facile platform for mass production of robust self-propelled tubular microengines. Tissue cells extracted from fruits of banana and apple, Musa acuminata and Malus domestica, are used as the support on which a thin platinum film is deposited by means of physical vapor deposition. Upon sonication of the cells/Pt-coated substrate in water, microscrolls of highly uniform sizes are spontaneously formed. Tubular microengines fabricated with the fruit cell assisted method exhibit a fast motion of ~100 bodylengths per s (~1 mm s-1). An extremely simple and affordable platform for mass production of the micromotors is crucial for the envisioned swarms of thousands and millions of autonomous micromotors performing biomedical and environmental remediation tasks.We report a facile platform for mass production of robust self-propelled tubular microengines. Tissue cells extracted from fruits of banana and apple, Musa acuminata and Malus domestica, are used as the support on which a thin platinum film is deposited by means of physical vapor deposition. Upon sonication of the cells/Pt-coated substrate in water, microscrolls of highly uniform sizes are spontaneously formed. Tubular microengines fabricated with the fruit cell assisted method exhibit a fast motion of ~100 bodylengths per s (~1 mm s-1). An extremely simple and affordable platform for mass production of the micromotors is crucial for the envisioned swarms of thousands and millions of autonomous micromotors performing biomedical and environmental remediation tasks. Electronic supplementary information (ESI) available: Related video. See DOI: 10.1039/c4nr03720k

  4. Effect of Loading Paths on HydroformingTubular Square Components

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The influence of loading path on tube hydroforming process is discussed in this paper with finiteelement simulation. Four different loading paths are utilized in simulating the forming process of square tubular component with hydroforming and the result of different loading path is presented. Among the result, the thickness distribution of bilinear loading path is the most uniform one. It shows that the increase of punch displacement in the stage of high pressure is beneficial to the forming of component for optimized stress condition.

  5. ELECTROLYTIC-PLASMA TREATMENT OF INNER SURFACE OF TUBULAR PRODUCTS

    Directory of Open Access Journals (Sweden)

    Yu. G. Alekseev

    2016-01-01

    Full Text Available While manufacturing a number of important tubular products stringent requirements have been imposed on quality of their inner surfaces. The well-known methods for inner surface treatment of pipes include sandblasting, chemical cleaning with acid reagents (oxalic, formic, sulfamic, orthophosphoric acids and electrochemical polishing. Disadvantages of the chemical method are cleaning-up irregularities, high metal removal, limited number of reagent application, complicated selection of reagent chemical composition and concentration, complicated and environmentally harmful recycling of waste chemicals, high cost of reagents. Low productivity at a high cost, as well as hazardous impact on personnel due to high dispersion of abrasive dust are considered as disadvantages of sandblasting. Electrochemical polishing is characterized by the following disadvantages: low processing productivity because supply of high currents is rather difficult due to electrolyte scattering capacity away from the main electrode action zone, limited length of the cavity to be treated due to heating of flexible current leads at operating current densities, application of expensive aggressive electrolytes and high costs of their recycling. A new method for polishing and cleaning of inner surfaces of tubular products based on electrolyte-plasma treatment has been developed. In comparison with the existing methods the proposed methods ensures quality processing with high intensity while applying non-toxic, environmentally friendly and cheap electrolytes. The paper presents results of investigations on technological specific features of electrolyte-plasma treatment for inner surfaces of tubular products: influence of slotted nozzle width, electrolyte flow and rate on stability of gas-vapor blanket, current density and productivity. Results of the research have made it possible to determine modes that provide stability and high productivity in the process of electrolyte

  6. Aerodynamic loads on a ball-obturated tubular projectile

    OpenAIRE

    Bry, William Arthur

    1982-01-01

    Approved for public release, distribution unlimited A tubular projectile is one with a hole bored along its longitudinal axis. The hole presents a problem in getting the round expelled from a gun. Some means of sealing the hole until the round clears the muzzle is required. A ball -obturator offers one practical means of accomplishing this without any accompanying FOD hazard. The ball-obturator, analogous to a common ballvalve, remains closed under the force of the expand...

  7. Study of maximum pressure for composite hepta-tubular powders

    Directory of Open Access Journals (Sweden)

    M. C. Gupta

    1959-10-01

    Full Text Available In this paper the expressions for maximum pressure occurring positions in the case of composite hepta-tubular powers used in conventional guns and the corresponding conditions have been derived under certain conditions, viz., the value of n, the ratio of specific heats, has been assumed to be the same for both the charges and the covolume corrections have not been neglected.

  8. Mechanical models for the self-organization of tubular patterns.

    Science.gov (United States)

    Guo, Chin-Lin

    2013-01-01

    Organogenesis, such as long tubule self-organization, requires long-range coordination of cell mechanics to arrange cell positions and to remodel the extracellular matrix. While the current mainstream in the field of tissue morphogenesis focuses primarily on genetics and chemical signaling, the influence of cell mechanics on the programming of patterning cues in tissue morphogenesis has not been adequately addressed. Here, we review experimental evidence and propose quantitative mechanical models by which cells can create tubular patterns.

  9. Lipasuria in acute pancreatitis: result of tubular dysfunction?

    Science.gov (United States)

    Muench, R; Buehler, H; Kehl, O; Ammann, R

    1987-01-01

    Lipase, in contrast to amylase, is completely reabsorbed by the proximal tubules after glomerular filtration. Therefore, no lipase is detectable in the unconcentrated urine according to the current opinion. The handling of lipase (detected with an enzyme-immunoassay) by the kidney was investigated in comparison with creatinine, amylase, and beta-2-microglobulin by clearance studies in acute pancreatitis (n = 10), burn injury (n = 4), glomerular proteinuria (n = 8), and controls without evidence of pancreatic or renal diseases (n = 5). In initial stages of acute pancreatitis a measurable clearance of lipase (mean: 49.6 microliters/min, range: 0.5-234) was found in association with corresponding increased clearances of beta-2-microglobulin (mean: 10.5 ml/min, range: 0.02-58.9) and of amylase (mean: 8.9 ml/min, range: 2.4-22.6) in nine of ten patients. This finding is consistent with a defect of tubular function. However, regression analysis failed to show a significant correlation between lipase and beta-2-microglobulin clearance. Repeated measurements during the course of pancreatitis in seven patients showed reversibility of tubular dysfunction. In patients with burn injury a similar elevation of clearances of beta-2-microglobulin and of amylase was found, but tubular dysfunction in this condition was not associated with lipasuria. In glomerular proteinuria a lipase clearance was found in two of five cases with moderate, and in the other three cases with severe impairment of creatinine clearance. beta-2-microglobulin clearance was normal in the former and only slightly elevated in the latter group. In conclusion lipase is measurable in the urine of most patients with acute pancreatitis as a result of a reversible tubular dysfunction.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Catalytic Tubular Microjet Propulsion Model for Endovascular Navigation

    OpenAIRE

    Sarkis, Bruno; Folio, David; Ferreira, Antoine

    2015-01-01

    International audience; This paper describes the propulsion of the catalytic tubular microjet using Navier-Stokes equations. Especially , the thrust capability of the microjet is outstanding compared with the other microsystems, but remains only partially understood. Studies have identified the internal precursory mechanisms of the propulsion of the microjet: its inner wall catalyzes the dismutation of aqueous hydrogen peroxide, and an oxygen bubble is then formed and migrates towards its wid...

  11. Evaluation of stress concentration for planar tubular joints

    Institute of Scientific and Technical Information of China (English)

    M.F.GHANAMEH; D.THEVENET; A.ZEGHLOUL

    2006-01-01

    In offshore tubular structures,a typical tubular joint may be subjected to three different types of basic loadings: axial,in-plane bending and out-of-plane bending,through its brace members. Each type will cause a different stress distribution at the joint intersection of structures. Moreover,the actual load condition of a tubular joint can be any combination of the above three basic load cases,for this reason,a combined loading was investigated in addition to these three basic loadings. This load is composed of an axial loading combined with a continuation of rotational bending loading obtained while rotate center of the brace around a circle. Different types of planar joints such as T,Y,X,K,DT,DY,DX,TY,TK,DTX,DTDY,and DTDK,with braces subjected to combined loading,were numerically analyzed to study the effect of those different cases of loading and different types of joints,on the stress concentration zone and values.

  12. Plastic deformation of tubular crystals by dislocation glide

    Science.gov (United States)

    Beller, Daniel A.; Nelson, David R.

    2016-09-01

    Tubular crystals, two-dimensional lattices wrapped into cylindrical topologies, arise in many contexts, including botany and biofilaments, and in physical systems such as carbon nanotubes. The geometrical principles of botanical phyllotaxis, describing the spiral packings on cylinders commonly found in nature, have found application in all these systems. Several recent studies have examined defects in tubular crystals associated with crystalline packings that must accommodate a fixed tube radius. Here we study the mechanics of tubular crystals with variable tube radius, with dislocations interposed between regions of different phyllotactic packings. Unbinding and separation of dislocation pairs with equal and opposite Burgers vectors allow the growth of one phyllotactic domain at the expense of another. In particular, glide separation of dislocations offers a low-energy mode for plastic deformations of solid tubes in response to external stresses, reconfiguring the lattice step by step. Through theory and simulation, we examine how the tube's radius and helicity affects, and is in turn altered by, the mechanics of dislocation glide. We also discuss how a sufficiently strong bending rigidity can alter or arrest the deformations of tubes with small radii.

  13. The rebirth of interest in renal tubular function.

    Science.gov (United States)

    Lowenstein, Jerome; Grantham, Jared J

    2016-06-01

    The measurement of glomerular filtration rate by the clearance of inulin or creatinine has evolved over the past 50 years into an estimated value based solely on plasma creatinine concentration. We have examined some of the misconceptions and misunderstandings of the classification of renal disease and its course, which have followed this evolution. Furthermore, renal plasma flow and tubular function, which in the past were estimated by the clearance of the exogenous aryl amine, para-aminohippurate, are no longer measured. Over the past decade, studies in experimental animals with reduced nephron mass and in patients with reduced renal function have identified small gut-derived, protein-bound uremic retention solutes ("uremic toxins") that are poorly filtered but are secreted into the lumen by organic anion transporters (OATs) in the proximal renal tubule. These are not effectively removed by conventional hemodialysis or peritoneal dialysis. Residual renal function, urine produced in patients with advanced renal failure or undergoing dialysis treatment, may represent, at least in part, secretion of fluid and uremic toxins, such as indoxyl sulfate, mediated by proximal tubule OATs and might serve as a useful survival function. In light of this new evidence of the physiological role of proximal tubule OATs, we suggest that measurement of renal tubular function and renal plasma flow may be of considerable value in understanding and managing chronic kidney disease. Data obtained in normal subjects indicate that renal plasma flow and renal tubular function might be measured by the clearance of the endogenous aryl amine, hippurate.

  14. A Tubular Biomaterial Construct Exhibiting a Negative Poisson's Ratio.

    Directory of Open Access Journals (Sweden)

    Jin Woo Lee

    Full Text Available Developing functional small-diameter vascular grafts is an important objective in tissue engineering research. In this study, we address the problem of compliance mismatch by designing and developing a 3D tubular construct that has a negative Poisson's ratio νxy (NPR. NPR constructs have the unique ability to expand transversely when pulled axially, thereby resulting in a highly-compliant tubular construct. In this work, we used projection stereolithography to 3D-print a planar NPR sheet composed of photosensitive poly(ethylene glycol diacrylate biomaterial. We used a step-lithography exposure and a stitch process to scale up the projection printing process, and used the cut-missing rib unit design to develop a centimeter-scale NPR sheet, which was rolled up to form a tubular construct. The constructs had Poisson's ratios of -0.6 ≤ νxy ≤ -0.1. The NPR construct also supports higher cellular adhesion than does the construct that has positive νxy. Our NPR design offers a significant advance in the development of highly-compliant vascular grafts.

  15. Plastic deformation of tubular crystals by dislocation glide.

    Science.gov (United States)

    Beller, Daniel A; Nelson, David R

    2016-09-01

    Tubular crystals, two-dimensional lattices wrapped into cylindrical topologies, arise in many contexts, including botany and biofilaments, and in physical systems such as carbon nanotubes. The geometrical principles of botanical phyllotaxis, describing the spiral packings on cylinders commonly found in nature, have found application in all these systems. Several recent studies have examined defects in tubular crystals associated with crystalline packings that must accommodate a fixed tube radius. Here we study the mechanics of tubular crystals with variable tube radius, with dislocations interposed between regions of different phyllotactic packings. Unbinding and separation of dislocation pairs with equal and opposite Burgers vectors allow the growth of one phyllotactic domain at the expense of another. In particular, glide separation of dislocations offers a low-energy mode for plastic deformations of solid tubes in response to external stresses, reconfiguring the lattice step by step. Through theory and simulation, we examine how the tube's radius and helicity affects, and is in turn altered by, the mechanics of dislocation glide. We also discuss how a sufficiently strong bending rigidity can alter or arrest the deformations of tubes with small radii.

  16. Aspirin-loaded electrospun poly(ε-caprolactone) tubular scaffolds: potential small-diameter vascular grafts for thrombosis prevention.

    Science.gov (United States)

    Del Gaudio, Costantino; Ercolani, Enrico; Galloni, Pierluca; Santilli, Federico; Baiguera, Silvia; Polizzi, Leonardo; Bianco, Alessandra

    2013-02-01

    Thrombosis is the main cause of failure of small-diameter synthetic vascular grafts when used for by-pass procedures. The development of bioresorbable vascular scaffolds with localized and sustained intra-luminal antithrombotic drug release could be considered a desirable improvement towards a valuable solution for this relevant clinical need. For this aim, we present the fabrication and characterization of aspirin-loaded electrospun poly(ε-caprolactone) tubular scaffolds as a vascular drug-delivery graft. Three different drug concentrations were considered (i.e., 1, 5 or 10 % w/w). Although a fibrous structure was clearly observed for all the collected scaffolds, aspirin content was directly implied in the final microstructure leading to a bimodal fiber diameter distribution and fused fibers at crossing-points (5 or 10 % w/w). Mechanical response highlighted a direct relationship for modulus and stress at break with the aspirin content, while the elongation at break was not remarkably different for the investigated cases. The temporal drug release was strongly dependent from the amount of loaded aspirin, reaching a steady state release after about 50 h. Finally, the adhesion assay confirmed the capability of the electrospun scaffolds to reduce platelet adhesion/aggregation onto aspirin loaded polymeric fibers. Aspirin-loaded electrospun tubular scaffold could represent a feasible candidate to develop a novel bioresorbable drug-releasing graft for small-diameter vessel replacements.

  17. Synthetic Completeness Proofs for Seligman-style Tableau Systems

    DEFF Research Database (Denmark)

    Jørgensen, Klaus Frovin; Blackburn, Patrick Rowan; Bolander, Thomas

    2016-01-01

    Seligman-style and labelled tableaus, but our results only covered the minimal hy- brid logic; in the present paper we provide completeness results for a wider range of hybrid logics and languages. We do so by adapting the synthetic approach to tableau completeness (due to Smullyan, and widely applied...

  18. Intragraft Tubular Vimentin and CD44 Expression Correlate With Long-Term Renal Allograft Function and Interstitial Fibrosis and Tubular Atrophy

    NARCIS (Netherlands)

    J. Kers; Y.C. Xu-Dubois; E. Rondeau; N. Claessen; M.M. Idu; J.J.T.H. Roelofs; F.J. Bemelman; R.J.M. ten Berge; S. Florquin

    2010-01-01

    Background. Development of interstitial fibrosis and tubular atrophy (IF/TA) is the main histologic feature involved in renal allograft deterioration. The aim of this study was to validate whether de novo tubular expression of CD44 (transmembrane glycoprotein) and vimentin (mesenchymal cell marker),

  19. Mathematical modeling of methyl ester concentration distribution in a continuous membrane tubular reactor and comparison with conventional tubular reactor

    Science.gov (United States)

    Talaghat, M. R.; Jokar, S. M.; Modarres, E.

    2017-04-01

    The reduction of fossil fuel resources and environmental issues made researchers find alternative fuels include biodiesels. One of the most widely used methods for production of biodiesel on a commercial scale is transesterification method. In this work, the biodiesel production by a transesterification method was modeled. Sodium hydroxide was considered as a catalyst to produce biodiesel from canola oil and methanol in a continuous tubular ceramic membranes reactor. As the Biodiesel production reaction from triglycerides is an equilibrium reaction, the reaction rate constants depend on temperature and related linearly to catalyst concentration. By using the mass balance for a membrane tubular reactor and considering the variation of raw materials and products concentration with time, the set of governing equations were solved by numerical methods. The results clearly show the superiority of membrane reactor than conventional tubular reactors. Afterward, the influences of molar ratio of alcohol to oil, weight percentage of the catalyst, and residence time on the performance of biodiesel production reactor were investigated.

  20. Analysis of constant tissue remodeling in Syrian hamster Harderian gland: intra-tubular and inter-tubular syncytial masses.

    Science.gov (United States)

    Coto-Montes, Ana; García-Macía, Marina; Caballero, Beatriz; Sierra, Verónica; Rodríguez-Colunga, María J; Reiter, Russel J; Vega-Naredo, Ignacio

    2013-05-01

    The Syrian hamster Harderian gland (HG) has a marked sexual dimorphism and exhibits an extraordinary rate of porphyrinogenesis. The physiological oxidative stress, derived from constant porphyrin production, is so high that the HG needs additional survival autophagic mechanisms to fight against this chronic exposure, provoking the triggering of a holocrine secretion in female glands that forms two types of secretory masses: intra-tubular-syncytial and inter-tubular-syncytial masses. The aim of this work was to study the development of this inter-tubular holocrine secretion. To approach this task, we have considered that the steps developed during the formation of the so-called invasive masses consist of the growth of epithelial cells, cell detachment from the basal lamina and invasion of surrounding tissues. The presence of these masses, particularly in the female HG, are closely linked to sexual dimorphism in redox balance and to alterations in the expression of certain factors such as cytokeratins, P-cadherin, matrix metalloproteinases, cathepsin H, proliferating cell nuclear antigen, p53, CD-31 and vascular endothelial growth factor, which seem to be involved in tissue remodeling. The results document unusual mechanisms of secretion in Syrian hamster HG: an extraordinary system of massive secretion through the conjunctive tissue, disrupting the branched structure of the gland.

  1. Hybrid vehicles

    Energy Technology Data Exchange (ETDEWEB)

    West, J.G.W. [Electrical Machines (United Kingdom)

    1997-07-01

    The reasons for adopting hybrid vehicles result mainly from the lack of adequate range from electric vehicles at an acceptable cost. Hybrids can offer significant improvements in emissions and fuel economy. Series and parallel hybrids are compared. A combination of series and parallel operation would be the ideal. This can be obtained using a planetary gearbox as a power split device allowing a small generator to transfer power to the propulsion motor giving the effect of a CVT. It allows the engine to run at semi-constant speed giving better fuel economy and reduced emissions. Hybrid car developments are described that show the wide range of possible hybrid systems. (author)

  2. Protein- and peptide-modified synthetic polymeric biomaterials.

    Science.gov (United States)

    Krishna, Ohm D; Kiick, Kristi L

    2010-01-01

    This review presents an overview on bio-hybrid approaches of integrating the structural and functional features of proteins and peptides with synthetic polymers and the resulting unique properties in such hybrids, with a focus on bioresponsive/bioactive systems with biomaterials applications. The review is divided in two broad sections. First, we describe several examples of bio-hybrids produced by combining versatile synthetic polymers with proteins/enzymes and drugs that have resulted in (1) hybrid materials based on responsive polymers, (2) responsive hydrogels based on enzyme-catalyzed reactions, protein-protein interactions and protein-drug sensing, and (3) dynamic hydrogels based on conformational changes of a protein. Next, we present hybrids produced by combining synthetic polymers with peptides, classified based on the properties of the peptide domain: (1) peptides with different conformations, such as alpha-helical, coiled-coil, and beta-sheet; (2) peptides derived from structural protein domains such as silk, elastin, titin, and collagen; and (3) peptides with other biofunctional properties such as cell-binding domains and enzyme-recognized degradation domains. (c) 2010 Wiley Periodicals, Inc.

  3. Membrane process treatment for greywater recycling: investigations on direct tubular nanofiltration.

    Science.gov (United States)

    Hourlier, F; Massé, A; Jaouen, P; Lakel, A; Gérente, C; Faur, C; Cloirec, P Le

    2010-01-01

    On-site greywater recycling and reuse is one of the main ways to reduce potable water requirement in urban areas. Direct membrane filtration is a promising technology to recycle greywater on-site. This study aimed at selecting a tubular nanofiltration (NF) membrane and its operating conditions in order to treat and reuse greywater in buildings. To do so, a synthetic greywater (SGW) was reconstituted in order to conduct experiments on a reproducible effluent. Then, three PCI NF membranes (AFC30, AFC40 and AFC80) having distinct molecular weight cut-offs were tested to recycle this SGW with a constant concentration at 25°C at two different transmembrane pressures (20 and 35 bar). The best results were obtained with AFC80 at 35 bar: the flux was close to 50 L m⁻²  h⁻¹, retentions of 95% for chemical oxygen demand and anionic surfactants were observed, and no Enterococcus were detected in the permeate. The performances of AFC80 were also evaluated on a real greywater: fluxes and retentions were similar to those observed on SGW. These results demonstrate the effectiveness of direct nanofiltration to recycle and reuse greywater.

  4. The Synthetic Cannabinoids Phenomenon.

    Science.gov (United States)

    Karila, Laurent; Benyamina, Amine; Blecha, Lisa; Cottencin, Olivier; Billieux, Joël

    2016-01-01

    « Spice » is generally used to describe the diverse types of herbal blends that encompass synthetic cannabinoids on the market. The emergence of smokable herbal products containing synthetic cannabinoids, which mimic the effects of cannabis, appears to become increasingly popular, in the new psychoactive substances landscape. In 2014, the existence of 134 different types of synthetic cannabinoids were reported by the European Union Early Warning System. These drugs are mainly sold online as an alternative to controlled and regulated psychoactive substances. They appear to have a life cycle of about 1-2 years before being replaced by a next wave of products. Legislation controlling these designer drugs has been introduced in many countries with the objective to limit the spread of existing drugs and control potential new analogs. The majority of the synthetic cannabinoids are full agonists at the CB1 receptor and do not contain tobacco or cannabis. They are becoming increasingly popular in adolescents, students and clubbers as an abused substance. Relatively high incidence of adverse effects associated with synthetic cannabinoids use has been documented in the literature. Numerous fatalities linked with their use and abuse have been reported. In this paper, we will review the available data regarding the use and effects of synthetic cannabinoids in humans in order to highlight their impact on public health. To reach this objective, a literature search was performed on two representative databases (Pubmed, Google Scholar), the Erowid Center website (a US non-profit educational organization that provides information about psychoactive plants and chemicals), and various governmental websites. The terms used for the database search were: "synthetic cannabinoids", "spice", "new psychoactive substances", and/or "substance use disorder", and/or "adverse effects", and/or "fatalities". The search was limited to years 2005 to 2016 due to emerging scientific literature at

  5. Forecasting elections in Europe: Synthetic models

    Directory of Open Access Journals (Sweden)

    Michael S. Lewis-Beck

    2015-01-01

    Full Text Available Scientific work on national election forecasting has become most developed for the United States case, where three dominant approaches can be identified: Structuralists, Aggregators, and Synthesizers. For European cases, election forecasting models remain almost exclusively Structuralist. Here we join together structural modeling and aggregate polling results, to form a hybrid, which we label a Synthetic Model. This model contains a political economy core, to which poll numbers are added (to tap omitted variables. We apply this model to a sample of three Western European countries: Germany, Ireland, and the United Kingdom. This combinatory strategy appears to offer clear forecasting gains, in terms of lead and accuracy.

  6. Synthetic focusing in ultrasound modulated tomography

    KAUST Repository

    Kuchment, Peter

    2010-09-01

    Several hybrid tomographic methods utilizing ultrasound modulation have been introduced lately. Success of these methods hinges on the feasibility of focusing ultrasound waves at an arbitrary point of interest. Such focusing, however, is difficult to achieve in practice. We thus propose a way to avoid the use of focused waves through what we call synthetic focusing, i.e. by reconstructing the would-be response to the focused modulation from the measurements corresponding to realistic unfocused waves. Examples of reconstructions from simulated data are provided. This non-technical paper describes only the general concept, while technical details will appear elsewhere. © 2010 American Institute of Mathematical Sciences.

  7. Synthetic guide star generation

    Science.gov (United States)

    Payne, Stephen A [Castro Valley, CA; Page, Ralph H [Castro Valley, CA; Ebbers, Christopher A [Livermore, CA; Beach, Raymond J [Livermore, CA

    2008-06-10

    A system for assisting in observing a celestial object and providing synthetic guide star generation. A lasing system provides radiation at a frequency at or near 938 nm and radiation at a frequency at or near 1583 nm. The lasing system includes a fiber laser operating between 880 nm and 960 nm and a fiber laser operating between 1524 nm and 1650 nm. A frequency-conversion system mixes the radiation and generates light at a frequency at or near 589 nm. A system directs the light at a frequency at or near 589 nm toward the celestial object and provides synthetic guide star generation.

  8. Drill pipes and casings utilizing multi-conduit tubular; Flerkanals roerstreng

    Energy Technology Data Exchange (ETDEWEB)

    Curlett, H.B.

    1997-04-23

    The invention relates to a multi-conduit tubular having fluid conduits and electrical conduits, with associated surface fluid and electrical commutators, and downhole sensors for providing surface monitors with instantaneous formation data. Each tubular includes a plurality of uniform linear conduits there through, with a gasket seal plate interposed between joined tubular for assuring a high pressure seal between joined conduits. the seal plate includes an intermediate electrical connector for connecting electrical conduit connectors of one tubular to another. A coupling collar with uniform diameter internal coarse and fine threads joins the tubular ends having similar threads by differential thread action without respective tubular rotation. Each tubular end includes an inter-engaging index recess and index lug, and drive recesses and lugs for maintaining angular registry of the tubular string and for driving one drill tubular with another. A fluid commutator includes a rotating shaft with passages connected to the tubular conduits, and rotating in a manifold having annular grooves in communication with the shaft passages and external fluid sources. An adaptor couples each commutator shaft passage to one or more tubular conduits. Slip rings on a quill shaft and stationary brush means provide electrical continuity from the electrical conduit wires to surface equipment. A cross-over sub includes formation parameter sensors and telemetry equipment in a blocked off portion of a fluid conduit. An annular accumulator connected with the well bore annulus applies a pressure thereto in response to downhole sensors to change the effective density of the drill mud. The multi-conduit tubular is further adapted for use as a well casing to provide downhole access of a plurality of fluids and electrical parameter sensors. 28 figs.

  9. Mathematical modeling of the area of tubular gas heater in the condensing mode of work

    OpenAIRE

    IRODOV V. F.; Bereziuk, G. G.

    2015-01-01

    Statement of the problem. Infrared tubular gas heaters are designed for burning gas, moving of the heated products of combustion with air inside the tubular heater and heating of the room where the heater is installed with the help of radiant and convective heat exchange with space of the room. Tubular gas heaters are simultaneously sources of heat supply and heating devices. Using of these heaters provides fuel economy and uniform distribution of comfortable heat. Maximum fuel economy can be...

  10. A tubular segmented-flow bioreactor for the infection of insect cells with recombinant baculovirus

    OpenAIRE

    Hu, Yu-Chen; Wang, Ming-Ying; Bentley, William E.

    1997-01-01

    A continuous process of insect cell (S f9) growth and baculovirus infection is tested with the sequential combination of a CSTR and a tubular reactor. A tubular infection reactor enables continuous introduction of baculovirus and therefore avoids the ‘passage effect’ observed in two-stage CSTR systems. Moreover, a tubular reactor can be used to test cell infection kinetics and the subsequent metabolism of infected insect cells. Unlike batch and CSTR culture, cells in a horizontally positioned...

  11. Construction of tubular polypyrrole-wrapped biomass-derived carbon nanospheres as cathode materials for lithium-sulfur batteries

    Science.gov (United States)

    Yu, Qiuhong; Lu, Yang; Peng, Tao; Hou, Xiaoyi; Luo, Rongjie; Wang, Yange; Yan, Hailong; Liu, Xianming; Kim, Jang-Kyo; Luo, Yongsong

    2017-03-01

    A promising hybrid material composed of tubular polypyrrole (T-PPy)-wrapped monodisperse biomass-derived carbon nanospheres (BCSs) was first synthesized successfully via a simple hydrothermal approach by using watermelon juice as the carbon source, and further used as an anchoring object for sulfur (S) of lithium-sulfur (Li-S) batteries. The use of BCSs with hydrophilic nature as a framework could provide large interface areas between the active materials and electrolyte, and improve the dispersion of T-PPy, which could help in the active material utilization. As a result, BCS@T-PPy/S as a cathode material exhibited a high capacity of 1143.6 mA h g-1 and delivered a stable capacity up to 685.8 mA h g-1 after 500 cycles at 0.5 C, demonstrating its promising application for rechargeable Li-S batteries.

  12. Numerical Simulation of the Effect of Air Distribution on Turbulent Flow and Combustion in a Tubular Heating Furnace

    Institute of Scientific and Technical Information of China (English)

    WangJuan; MaoYu; LiLihong

    2005-01-01

    A three-dimension full-size numerical simulation of the effect of air distribution on turbulent flow and combustion in a tubular heating furnace was carried out. A standard k - ε turbulent model, a simplified PDF combustion model and a discrete ordinate transfer radiation model were used. The hybrid grid combining a structured and a non-structured grid was generated without any simplification of the complicated geometric configuration around the burner. It was found that the multistage combustion could reduce and control the peak value of temperature. At the same time, it was concluded that the amount of primary air had little effect on the global distribution of velocity and temperature in the furnace, but a great effect on that around the burner. It is recommended that 45%- 65% of the total amount of air be taken in in primary air inlets in the furnace. All the results are important to optimize the combustion progress.

  13. Braided tubular superelastic cables provide improved spinal stability compared to multifilament sublaminar cables.

    Science.gov (United States)

    Tremblay, Jaëlle; Mac-Thiong, Jean-Marc; Brailovski, Vladimir; Petit, Yvan

    2015-09-01

    This study investigates the use of braided tubular superelastic cables, previously used for sternum closure following sternotomy, as sublaminar fixation method. It compares the biomechanical performance of spinal instrumentation fixation systems with regular sublaminar cables and proprietary superelastic cables. A hybrid experimental protocol was applied to six porcine L1-L4 spinal segments to compare multifilament sublaminar cables (Atlas, Medtronic Sofamor Danek, Memphis, TN) with proprietary superelastic cables. First, intact total range of motion was determined for all specimens using pure moment loading. Second, pure moments were imposed to the instrumented specimens until these intact total ranges of motion were reproduced. Compared to the intact specimens, the use of superelastic cables resulted in stiffer instrumented specimens than the use of multifilament cables for all the loading modes except axial torsion. Consequently, the superelastic cables limited the instrumented segments mobility more than the multifilament cables. Spinal instrumentation fixation systems using superelastic cables could be a good alternative to conventional sublaminar cables as it maintains a constant stabilization of the spine during loading.

  14. Open Tubular Microreactor with Enzyme Functionalized Micro- fluidic Channel for Amperometric Detection of Glucose

    Institute of Scientific and Technical Information of China (English)

    张蕾; 曲平; 盛金; 雷建平; 鞠烷先

    2012-01-01

    A simple and efficient method using enzyme immobilized microfluidic channel as open tubular microreactor was designed for amperometric detection of glucose. The microreactor was composed of a polydimethylsilicone/ glass hybrid device with three reservoirs, a cooling cave and a 6 cm capillary with a sampling fracture as micro-channel. The microchannel was further modified by thermal polymerization, followed by covalently attaching with glucose oxidase. Through fracture sampling and electrochromatography separation, the production via enzymatic reaction was determinated by Pt electrode at the end of capillary. The linear range for the detection of glucose was 0.05--7.5 mmol·L-1 with detection limit of 23μmol.L-1 The inter-and intra-chip reproducibilities for determination of 2.5 mmol-L-1 glucose were 98.5% (n=5) and 96.0% (n=5), respectively. With the advantage of flexible assembly, rapid efficiency, good stability and low-cost, this microreactor provided a potential platform for estab- lishing a portable enzyme-based chemical detection system in practical application.

  15. Tubular overexpression of gremlin induces renal damage susceptibility in mice.

    Directory of Open Access Journals (Sweden)

    Alejandra Droguett

    Full Text Available A growing number of patients are recognized worldwide to have chronic kidney disease. Glomerular and interstitial fibrosis are hallmarks of renal progression. However, fibrosis of the kidney remains an unresolved challenge, and its molecular mechanisms are still not fully understood. Gremlin is an embryogenic gene that has been shown to play a key role in nephrogenesis, and its expression is generally low in the normal adult kidney. However, gremlin expression is elevated in many human renal diseases, including diabetic nephropathy, pauci-immune glomerulonephritis and chronic allograft nephropathy. Several studies have proposed that gremlin may be involved in renal damage by acting as a downstream mediator of TGF-β. To examine the in vivo role of gremlin in kidney pathophysiology, we generated seven viable transgenic mouse lines expressing human gremlin (GREM1 specifically in renal proximal tubular epithelial cells under the control of an androgen-regulated promoter. These lines demonstrated 1.2- to 200-fold increased GREM1 expression. GREM1 transgenic mice presented a normal phenotype and were without proteinuria and renal function involvement. In response to the acute renal damage cause by folic acid nephrotoxicity, tubule-specific GREM1 transgenic mice developed increased proteinuria after 7 and 14 days compared with wild-type treated mice. At 14 days tubular lesions, such as dilatation, epithelium flattening and hyaline casts, with interstitial cell infiltration and mild fibrosis were significantly more prominent in transgenic mice than wild-type mice. Tubular GREM1 overexpression was correlated with the renal upregulation of profibrotic factors, such as TGF-β and αSMA, and with increased numbers of monocytes/macrophages and lymphocytes compared to wild-type mice. Taken together, our results suggest that GREM1-overexpressing mice have an increased susceptibility to renal damage, supporting the involvement of gremlin in renal damage

  16. Tubular algebras and affine Kac-Moody algebras

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The purpose of this paper is to construct quotient algebras L(A)1C/I(A) of complex degenerate composition Lie algebras L(A)1C by some ideals, where L(A)1C is defined via Hall algebras of tubular algebras A, and to prove that the quotient algebras L(A)1C/I(A) are isomorphic to the corresponding affine Kac-Moody algebras. Moreover, it is shown that the Lie algebra Lre(A)1C generated by A-modules with a real root coincides with the degenerate composition Lie algebra L(A)1C generated by simple A-modules.

  17. Tubular algebras and affine Kac-Moody algebras

    Institute of Scientific and Technical Information of China (English)

    Zheng-xin CHEN; Ya-nan LIN

    2007-01-01

    The purpose of this paper is to construct quotient algebras L(A)C1/I(A) of complex degenerate composition Lie algebras L(A)C1 by some ideals, where L(A)C1 is defined via Hall algebras of tubular algebras A, and to prove that the quotient algebras L(A)C1/I(A) are isomorphic to the corresponding affine Kac-Moody algebras. Moreover, it is shown that the Lie algebra Lre(A)C1 generated by A-modules with a real root coincides with the degenerate composition Lie algebra L(A)C1 generated by simple A-modules.

  18. Partial oxidation of methane to syngas in tubular oxygenpermeable reactor

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A dense Ba0.5Sr0.5Co0.8Fe0.2O3-δ membrane tube was prepared by the extruding method. Furthermore, a membrane reactor with this tubular membrane was successfully applied to partial oxidation of methane (POM) reaction,in which the separation of oxygen from air and the partial oxidation of methane are integrated in one process. At 875℃,94% of methane conversion, 98% of CO selectivity, 95% of H2 selectivity, and as high as 8.8 mL/(min @cm2) of oxygen flux were obtained. In POM reaction condition, the membrane tube shows a very good stability.

  19. Superradiance at the localization-delocalization crossover in tubular chlorosomes

    CERN Document Server

    Molina, Rafael A; Somoza, Alejandro; Chen, Lipeng; Zhao, Yang

    2016-01-01

    We study the effect of disorder on spectral properties of tubular chlorosomes in green sulfur bacteria Cf. aurantiacus. Employing a Frenkel-exciton Hamiltonian with diagonal and off-diagonal disorder consistent with spectral and structural studies, we analyze excitonic localization and spectral statistics of the chlorosomes. A size-dependent localization-delocalization crossover is found to occur as a function of the excitonic energy. The crossover energy region coincides with the more optically active states with maximized superradiance, and is, consequently, more conducive for energy transfer.

  20. Giant Candida mycetoma in an ascending aorta tubular graft.

    Science.gov (United States)

    Di Benedetto, Giuseppe; Citro, Rodolfo; Longobardi, Antonio; Mastrogiovanni, Generoso; Panza, Antonio; Iesu, Severino; Bossone, Eduardo

    2013-09-01

    We report the case of a 46-year-old male hospitalized for abdominal pain and fever with history of a David procedure followed by an aortic valve replacement due to severe aortic regurgitation. Transesophageal echocardiography (TEE) and computed tomography showed a large mass floating in the aorta. After surgical excision of the vegetation, attached to the Dacron prosthesis, histological examination revealed Candida hyphae and spores confirming the diagnosis of a mycetoma in an ascending aorta tubular graft. At six-month follow-up, the patient was in good clinical condition without recurrence of the fungal mass on TEE. © 2013 Wiley Periodicals, Inc.

  1. Point-like inclusion interactions in tubular membranes

    CERN Document Server

    Vahid, Afshin

    2015-01-01

    We analytically study membrane mediated interactions between inclusions embedded in a tubular membrane. We model inclusions as constraints coupled to the curvature tensor of the membrane tube. First, as special test cases, we analyze the interaction between ring and rod shaped inclusions. Using Monte Carlo simulations, we further show how point-like inclusions interact to form linear aggregates. Our results reveal that depending on the hard-core radius of the inclusions, they arrange into either lines or rings to globally minimize the curvature energy of the membrane.

  2. Distal renal tubular acidosis and amelogenesis imperfecta: A rare association

    Directory of Open Access Journals (Sweden)

    P Ravi

    2013-01-01

    Full Text Available Renal tubular acidosis (RTA is characterized by a normal anion gap with hyperchloremic metabolic acidosis. Primary distal RTA (type I is the most common RTA in children. Childhood presentation of distal RTA includes vomiting, failure to thrive, metabolic acidosis, and hypokalemia. Amelogenesis imperfecta (AI represents a condition where the dental enamel and oral tissues are affected in an equal manner resulting in the hypoplastic or hypopigmented teeth. We report a 10-year-old girl, previously asymptomatic presented with the hypokalemic paralysis and on work-up found out to have type I RTA. The discoloration of teeth and enamel was diagnosed as AI.

  3. Type 4 renal tubular acidosis in a kidney transplant recipient

    Directory of Open Access Journals (Sweden)

    Manjunath Kulkarni

    2016-02-01

    Full Text Available We report a case of a 66-year-old diabetic patient who presented with muscle weakness 2 weeks after kidney transplantation. Her immunosuppressive regimen included tacrolimus, mycophenolate mofetil, and steroids. She was found to have hyperkalemia and normal anion gap metabolic acidosis. Tacrolimus levels were in therapeutic range. All other drugs such as beta blockers and trimethoprim – sulfamethoxazole were stopped. She did not respond to routine antikalemic measures. Further evaluation revealed type 4 renal tubular acidosis. Serum potassium levels returned to normal after starting sodium bicarbonate and fludrocortisone therapy. Though hyperkalemia is common in kidney transplant recipients, determining exact cause can guide specific treatment.

  4. Type 4 renal tubular acidosis in a kidney transplant recipient.

    Science.gov (United States)

    Kulkarni, Manjunath

    2016-02-01

    We report a case of a 66-year-old diabetic patient who presented with muscle weakness 2 weeks after kidney transplantation. Her immunosuppressive regimen included tacrolimus, mycophenolate mofetil, and steroids. She was found to have hyperkalemia and normal anion gap metabolic acidosis. Tacrolimus levels were in therapeutic range. All other drugs such as beta blockers and trimethoprim - sulfamethoxazole were stopped. She did not respond to routine antikalemic measures. Further evaluation revealed type 4 renal tubular acidosis. Serum potassium levels returned to normal after starting sodium bicarbonate and fludrocortisone therapy. Though hyperkalemia is common in kidney transplant recipients, determining exact cause can guide specific treatment.

  5. Expression of cleaved caspase-3 in renal tubular cells in Plasmodium falciparum malaria patients.

    Science.gov (United States)

    Wichapoon, Benjamas; Punsawad, Chuchard; Viriyavejakul, Parnpen

    2017-01-01

    In Plasmodium falciparum malaria, the clinical manifestation of acute kidney injury (AKI) is commonly associated with acute tubular necrosis (ATN) in the kidney tissues. Renal tubular cells often exhibit various degrees of cloudy swelling, cell degeneration, and frank necrosis. To study individual cell death, this study evaluates the degree of renal tubular necrosis in association with apoptosis in malarial kidneys. Kidney tissues from P. falciparum malaria with AKI (10 cases), and without AKI (10 cases) were evaluated for tubular pathology. Normal kidney tissues from 10 cases served as controls. Tubular necrosis was assessed quantitatively in kidney tissues infected with P. falciparum malaria, based on histopathological evaluation. In addition, the occurrence of apoptosis was investigated using cleaved caspase-3 marker. Correlation between tubular necrosis and apoptosis was analyzed. Tubular necrosis was found to be highest in P. falciparum malaria patients with AKI (36.44% ± 3.21), compared to non-AKI (15.88% ± 1.63) and control groups (2.58% ± 0.39) (all p < 0.001). In the AKI group, the distal tubules showed a significantly higher degree of tubular necrosis than the proximal tubules (p = 0.021) and collecting tubules (p = 0.033). Tubular necrosis was significantly correlated with the level of serum creatinine (r = 0.596, p = 0.006), and the occurrence of apoptosis (r = 0.681, p = 0.001). In malarial AKI, the process of apoptosis occurs in ATN. © 2016 Asian Pacific Society of Nephrology.

  6. Amylase/creatinine clearance ratio and tubular proteinuria in acute pancreatitis.

    Science.gov (United States)

    Lankisch, P G; Wolfrum, D I; Koop, H; Winckler, K

    1979-01-01

    Amylase/creatinine clearance ratio (CAm/CCr), urinary protein concentration and urinary protein pattern were studied in 102 samples from 27 patients with acute pancreatitis and in 46 controls. Raised CAm/CCr, proteinuria and a tubular protein pattern were present in 74, 56 and 96% of the patients, respectively. However, CAm/CCr and proteinuria and CAm/CCr and tubular protein pattern were not correlated. These results do not support the suggestion that an elevated CAm/CCr in acute pancreatitis is due to generalized tubular protein reabsorption failure presenting with tubular proteinuria.

  7. Stem cell factor expression after renal ischemia promotes tubular epithelial survival.

    Directory of Open Access Journals (Sweden)

    Geurt Stokman

    Full Text Available BACKGROUND: Renal ischemia leads to apoptosis of tubular epithelial cells and results in decreased renal function. Tissue repair involves re-epithelialization of the tubular basement membrane. Survival of the tubular epithelium following ischemia is therefore important in the successful regeneration of renal tissue. The cytokine stem cell factor (SCF has been shown to protect the tubular epithelium against apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: In a mouse model for renal ischemia/reperfusion injury, we studied how expression of c-KIT on tubular epithelium and its ligand SCF protect cells against apoptosis. Administration of SCF specific antisense oligonucleotides significantly decreased specific staining of SCF following ischemia. Reduced SCF expression resulted in impaired renal function, increased tubular damage and increased tubular epithelial apoptosis, independent of inflammation. In an in vitro hypoxia model, stimulation of tubular epithelial cells with SCF activated survival signaling and decreased apoptosis. CONCLUSIONS/SIGNIFICANCE: Our data indicate an important role for c-KIT and SCF in mediating tubular epithelial cell survival via an autocrine pathway.

  8. Synthetic Aperture Radar Interferometry

    Science.gov (United States)

    Rosen, P. A.; Hensley, S.; Joughin, I. R.; Li, F.; Madsen, S. N.; Rodriguez, E.; Goldstein, R. M.

    1998-01-01

    Synthetic aperture radar interferometry is an imaging technique for measuring the topography of a surface, its changes over time, and other changes in the detailed characteristics of the surface. This paper reviews the techniques of interferometry, systems and limitations, and applications in a rapidly growing area of science and engineering.

  9. Biodegradable synthetic bone composites

    Science.gov (United States)

    Liu, Gao; Zhao, Dacheng; Saiz, Eduardo; Tomsia, Antoni P.

    2013-01-01

    The invention provides for a biodegradable synthetic bone composition comprising a biodegradable hydrogel polymer scaffold comprising a plurality of hydrolytically unstable linkages, and an inorganic component; such as a biodegradable poly(hydroxyethylmethacrylate)/hydroxyapatite (pHEMA/HA) hydrogel composite possessing mineral content approximately that of human bone.

  10. Synthetic growth reference charts

    NARCIS (Netherlands)

    Hermanussen, Michael; Stec, Karol; Aßmann, Christian; Meigen, Christof; Van Buuren, Stef

    2016-01-01

    Objectives: To reanalyze the between-population variance in height, weight, and body mass index (BMI), and to provide a globally applicable technique for generating synthetic growth reference charts. Methods: Using a baseline set of 196 female and 197 male growth studies published since 1831, common

  11. Synthetic studies towards bottromycin

    Directory of Open Access Journals (Sweden)

    Stefanie Ackermann

    2012-10-01

    Full Text Available Thio-Ugi reactions are described as an excellent synthetic tool for the synthesis of sterically highly hindered endothiopeptides. S-Methylation and subsequent amidine formation can be carried out in an inter- as well as in an intramolecular fashion. The intramolecular approach allows the synthesis of the bottromycin ring system in a straightforward manner.

  12. Synthetic Plant Defense Elicitors

    Directory of Open Access Journals (Sweden)

    Yasemin eBektas

    2015-01-01

    Full Text Available To defend themselves against invading pathogens plants utilize a complex regulatory network that coordinates extensive transcriptional and metabolic reprogramming. Although many of the key players of this immunity-associated network are known, the details of its topology and dynamics are still poorly understood. As an alternative to forward and reverse genetic studies, chemical genetics-related approaches based on bioactive small molecules have gained substantial popularity in the analysis of biological pathways and networks. Use of such molecular probes can allow researchers to access biological space that was previously inaccessible to genetic analyses due to gene redundancy or lethality of mutations. Synthetic elicitors are small drug like molecules that induce plant defense responses, but are distinct from known natural elicitors of plant immunity. While the discovery of the some synthetic elicitors had already been reported in the 1970s, recent breakthroughs in combinatorial chemical synthesis now allow for inexpensive high-throughput screens for bioactive plant defense-inducing compounds. Along with powerful reverse genetics tools and resources available for model plants and crop systems, comprehensive collections of new synthetic elicitors will likely allow plant scientists to study the intricacies of plant defense signaling pathways and networks in an unparalleled fashion. As synthetic elicitors can protect crops from diseases, without the need to be directly toxic for pathogenic organisms, they may also serve as promising alternatives to conventional biocidal pesticides, which often are harmful for the environment, farmers and consumers. Here we are discussing various types of synthetic elicitors that have been used for studies on the plant immune system, their modes-of-action as well as their application in crop protection.

  13. Synthetic River Valleys

    Science.gov (United States)

    Brown, R.; Pasternack, G. B.

    2011-12-01

    The description of fluvial form has evolved from anecdotal descriptions to artistic renderings to 2D plots of cross section or longitudinal profiles and more recently 3D digital models. Synthetic river valleys, artificial 3D topographic models of river topography, have a plethora of potential applications in fluvial geomorphology, and the earth sciences in general, as well as in computer science and ecology. Synthetic river channels have existed implicitly since approximately the 1970s and can be simulated from a variety of approaches spanning the artistic and numerical. An objective method of synthesizing 3D stream topography based on reach scale attributes would be valuable for sizing 3D flumes in the physical and numerical realms, as initial input topography for morphodynamic models, stream restoration design, historical reconstruction, and mechanistic testing of interactions of channel geometric elements. Quite simply - simulation of synthetic channel geometry of prescribed conditions can allow systematic evaluation of the dominant relationships between river flow and geometry. A new model, the control curve method, is presented that uses hierarchically scaled parametric curves in over-lapping 2D planes to create synthetic river valleys. The approach is able to simulate 3D stream geometry from paired 2D descriptions and can allow experimental insight into form-process relationships in addition to visualizing past measurements of channel form that are limited to two dimension descriptions. Results are presented that illustrate the models ability to simulate fluvial topography representative of real world rivers as well as how channel geometric elements can be adjusted. The testing of synthetic river valleys would open up a wealth of knowledge as to why some 3D attributes of river channels are more prevalent than others as well as bridging the gap between the 2D descriptions that have dominated fluvial geomorphology the past century and modern, more complete, 3D

  14. Graphene Hybrid Materials in Gas Sensing Applications

    Directory of Open Access Journals (Sweden)

    Usman Latif

    2015-12-01

    Full Text Available Graphene, a two dimensional structure of carbon atoms, has been widely used as a material for gas sensing applications because of its large surface area, excellent conductivity, and ease of functionalization. This article reviews the most recent advances in graphene hybrid materials developed for gas sensing applications. In this review, synthetic approaches to fabricate graphene sensors, the nano structures of hybrid materials, and their sensing mechanism are presented. Future perspectives of this rapidly growing field are also discussed.

  15. Surface and interfacial creases in a bilayer tubular soft tissue

    Science.gov (United States)

    Razavi, Mir Jalil; Pidaparti, Ramana; Wang, Xianqiao

    2016-08-01

    Surface and interfacial creases induced by biological growth are common types of instability in soft biological tissues. This study focuses on the criteria for the onset of surface and interfacial creases as well as their morphological evolution in a growing bilayer soft tube within a confined environment. Critical growth ratios for triggering surface and interfacial creases are investigated both analytically and numerically. Analytical interpretations provide preliminary insights into critical stretches and growth ratios for the onset of instability and formation of both surface and interfacial creases. However, the analytical approach cannot predict the evolution pattern of the model after instability; therefore nonlinear finite element simulations are carried out to replicate the poststability morphological patterns of the structure. Analytical and computational simulation results demonstrate that the initial geometry, growth ratio, and shear modulus ratio of the layers are the most influential factors to control surface and interfacial crease formation in this soft tubular bilayer. The competition between the stretch ratios in the free and interfacial surfaces is one of the key driving factors to determine the location of the first crease initiation. These findings may provide some fundamental understanding in the growth modeling of tubular biological tissues such as esophagi and airways as well as offering useful clues into normal and pathological functions of these tissues.

  16. Nano-tubular cellulose for bioprocess technology development.

    Directory of Open Access Journals (Sweden)

    Athanasios A Koutinas

    Full Text Available Delignified cellulosic material has shown a significant promotional effect on the alcoholic fermentation as yeast immobilization support. However, its potential for further biotechnological development is unexploited. This study reports the characterization of this tubular/porous cellulosic material, which was done by SEM, porosimetry and X-ray powder diffractometry. The results showed that the structure of nano-tubular cellulose (NC justifies its suitability for use in "cold pasteurization" processes and its promoting activity in bioprocessing (fermentation. The last was explained by a glucose pump theory. Also, it was demonstrated that crystallization of viscous invert sugar solutions during freeze drying could not be otherwise achieved unless NC was present. This effect as well as the feasibility of extremely low temperature fermentation are due to reduction of the activation energy, and have facilitated the development of technologies such as wine fermentations at home scale (in a domestic refrigerator. Moreover, NC may lead to new perspectives in research such as the development of new composites, templates for cylindrical nano-particles, etc.

  17. Radiologic findings of tubular adenoma of the breast

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Mi Gyoung; Oh, Ki Keun [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    1996-10-01

    Tubular adenoma (TA) is known as a rare lesion of the breast which is difficult to diagnosis preoperatively because of its rarity and similarity to fibroadenoma. Hence, our purpose is to suggest the characteristic sonographic features for its correct diagnosis. We retrospectively analyzed the clinical data and mammographic and sonographic findings. of seven patients(mean age, 23) who during the previous five years had presented at our hospital with pathologically-proven tubular adenoma. TA was misdiagnosed as fibroadenoma, since on physical examination of these young females, the lesions presented a palpable, non-tender mass. Mammographically, they showed a well defined mass similar to fibroadenoma. However, sonographic findings were characteristic of TA and compared to fibroadenoma, showed a well demarcated and smooth bordered mass with transverse long axis, posterior enhancement and homogeneous lower internal echogenecity. No case showed lateral wall refractive shadowing. In young females, the clinical and mammographic findings of TA are similar to those of fibroadenoma. However, sonographic findings of TA can, be helpful in the differential diagnosis of this entity and fibroadenoma.

  18. Toward automated cochlear implant insertion using tubular manipulators

    Science.gov (United States)

    Granna, Josephine; Rau, Thomas S.; Nguyen, Thien-Dang; Lenarz, Thomas; Majdani, Omid; Burgner-Kahrs, Jessica

    2016-03-01

    During manual cochlear implant electrode insertion the surgeon is at risk to damage the intracochlear fine-structure, as the electrode array is inserted through a small opening in the cochlea blindly with little force-feedback. This paper addresses a novel concept for cochlear electrode insertion using tubular manipulators to reduce risks of causing trauma during insertion and to automate the insertion process. We propose a tubular manipulator incorporated into the electrode array composed of an inner wire within a tube, both elastic and helically shaped. It is our vision to use this manipulator to actuate the initially straight electrode array during insertion into the cochlea by actuation of the wire and tube, i.e. translation and slight axial rotation. In this paper, we evaluate the geometry of the human cochlea in 22 patient datasets in order to derive design requirements for the manipulator. We propose an optimization algorithm to automatically determine the tube set parameters (curvature, torsion, diameter, length) for an ideal final position within the cochlea. To prove our concept, we demonstrate that insertion can be realized in a follow-the-leader fashion for 19 out of 22 cochleas. This is possible with only 4 different tube/wire sets.

  19. Advances in tubular solid oxide fuel cell technology

    Energy Technology Data Exchange (ETDEWEB)

    Singhal, S.C. [Westinghouse Electric Corp., Pittsburgh, PA (United States)

    1996-12-31

    The design, materials and fabrication processes for the earlier technology Westinghouse tubular geometry cell have been described in detail previously. In that design, the active cell components were deposited in the form of thin layers on a ceramic porous support tube (PST). The tubular design of these cells and the materials used therein have been validated by successful electrical testing for over 65,000 h (>7 years). In these early technology PST cells, the support tube, although sufficiently porous, presented an inherent impedance to air flow toward air electrode. In order to reduce such impedance to air flow, the wall thickness of the PST was first decreased from the original 2 mm (the thick-wall PST) to 1.2 mm (the thin-wall PST). The calcia-stabilized zirconia support tube has now been completely eliminated and replaced by a doped lanthanum manganite tube in state-of-the-art SOFCs. This doped lanthanum manganite tube is extruded and sintered to about 30 to 35 percent porosity, and serves as the air electrode onto which the other cell components are fabricated in thin layer form. These latest technology cells are designated as air electrode supported (AES) cells.

  20. Additive manufacturing of patient-specific tubular continuum manipulators

    Science.gov (United States)

    Amanov, Ernar; Nguyen, Thien-Dang; Burgner-Kahrs, Jessica

    2015-03-01

    Tubular continuum robots, which are composed of multiple concentric, precurved, elastic tubes, provide more dexterity than traditional surgical instruments at the same diameter. The tubes can be precurved such that the resulting manipulator fulfills surgical task requirements. Up to now the only material used for the component tubes of those manipulators is NiTi, a super-elastic shape-memory alloy of nickel and titan. NiTi is a cost-intensive material and fabrication processes are complex, requiring (proprietary) technology, e.g. for shape setting. In this paper, we evaluate component tubes made of 3 different thermoplastic materials (PLA, PCL and nylon) using fused filament fabrication technology (3D printing). This enables quick and cost-effective production of custom, patient-specific continuum manipulators, produced on site on demand. Stress-strain and deformation characteristics are evaluated experimentally for 16 fabricated tubes of each thermoplastic with diameters and shapes equivalent to those of NiTi tubes. Tubes made of PCL and nylon exhibit properties comparable to those made of NiTi. We further demonstrate a tubular continuum manipulator composed of 3 nylon tubes in a transnasal, transsphenoidal skull base surgery scenario in vitro.

  1. Tubular g-C3 N4 Isotype Heterojunction: Enhanced Visible-Light Photocatalytic Activity through Cooperative Manipulation of Oriented Electron and Hole Transfer.

    Science.gov (United States)

    Tong, Zhenwei; Yang, Dong; Sun, Yuanyuan; Nan, Yanhu; Jiang, Zhongyi

    2016-08-01

    A tubular g-C3 N4 isotype heterojunction (TCNH) photocatalyst was designed for cooperative manipulation of the oriented transfer of photogenerated electrons and holes to pursue high catalytic performance. The adduct of cyanuric acid and melamine (CA·M) is first hydrothermally treated to assemble into hexagonal prism crystals; then the hybrid precursors of urea and CA·M crystals are calcined to form tubular g-C3 N4 isotype heterojunctions. Upon visible-light irradiation, the photogenerated electrons transfer from g-C3 N4 (CA·M) to g-C3 N4 (urea) driven by the conduction band offset of 0.05 eV, while the photogenerated holes transfer from g-C3 N4 (urea) to g-C3 N4 (CA·M) driven by the valence band offset of 0.18 eV, which renders oriented transfer of the charge carriers across the heterojunction interface. Meanwhile, the tubular structure of TCNH is favorable for oriented electron transfer along the longitudinal dimension, which greatly decreases the chance of charge carrier recombination. Consequently, TCNH exhibits a high hydrogen evolution rate of 63 μmol h(-1) (0.04 g, λ > 420 nm), which is nearly five times of the pristine g-C3 N4 and higher than most of the existing g-C3 N4 photocatalysts. This study demonstrates that isotype heterojunction structure and tubular structure can jointly manipulate the oriented transfer of electrons and holes, thus facilitating the visible-light photocatalysis.

  2. Synthetic virology: engineering viruses for gene delivery.

    Science.gov (United States)

    Guenther, Caitlin M; Kuypers, Brianna E; Lam, Michael T; Robinson, Tawana M; Zhao, Julia; Suh, Junghae

    2014-01-01

    The success of gene therapy relies heavily on the performance of vectors that can effectively deliver transgenes to desired cell populations. As viruses have evolved to deliver genetic material into cells, a prolific area of research has emerged over the last several decades to leverage the innate properties of viruses as well as to engineer new features into them. Specifically, the field of synthetic virology aims to capitalize on knowledge accrued from fundamental virology research in order to design functionally enhanced gene delivery vectors. The enhanced viral vectors, or 'bionic' viruses, feature engineered components, or 'parts', that are natural (intrinsic to viruses or from other organisms) and synthetic (such as man-made polymers or inorganic nanoparticles). Various design strategies--rational, combinatorial, and pseudo-rational--have been pursued to create the hybrid viruses. The gene delivery vectors of the future will likely criss-cross the boundaries between natural and synthetic domains to harness the unique strengths afforded by the various functional parts that can be grafted onto virus capsids. Such research endeavors will further expand and enable enhanced control over the functional capacity of these nanoscale devices for biomedicine.

  3. These Synthetic Times

    Institute of Scientific and Technical Information of China (English)

    KIT GILLET

    2008-01-01

    @@ Already slated to be one of the most important cultural events in the buildup to this summer's Olympic games, Synthetic Times-Media Art China 2008 will feature the works of more than 30 artists from around the world. Upwards of 40 media art installations will be exhibited in the National Art Museum of China alone, along with performances, workshops, presentations, and discussion panels focusing on the art works and the growth of media art as a discipline.

  4. Synthetic gases production

    Energy Technology Data Exchange (ETDEWEB)

    Mazaud, J.P.

    1996-06-01

    The natural gas or naphtha are the main constituents used for the production of synthetic gases. Several production ways of synthetic gases are industrially used as for example the natural gas or naphtha catalytic reforming, the selective oxidation of natural gas or heavy fuels and the coal oxy-vapo-gasification. The aim of this work is to study the different steps of production and treatment of the synthetic gases by the way of catalytic reforming. The first step is the desulfurization of the hydrocarbons feedstocks. The process used in industry is described. Then is realized the catalytic hydrocarbons reforming process. After having recalled some historical data on the catalytic reforming, the author gives the reaction kinetics and thermodynamics. The possible reforming catalysts, industrial equipments and furnaces designs are then exposed. The carbon dioxide is a compound easily obtained during the reforming reactions. It is a wasteful and harmful component which has to be extracted of the gaseous stream. The last step is then the gases de-carbonation. Two examples of natural gas or naphtha reforming reactions are at last given: the carbon monoxide conversion by steam and the carbon oxides reactions with hydrogen (methanization). (O.M.). 8 figs., 6 tabs.

  5. Synthetic biology in plastids.

    Science.gov (United States)

    Scharff, Lars B; Bock, Ralph

    2014-06-01

    Plastids (chloroplasts) harbor a small gene-dense genome that is amenable to genetic manipulation by transformation. During 1 billion years of evolution from the cyanobacterial endosymbiont to present-day chloroplasts, the plastid genome has undergone a dramatic size reduction, mainly as a result of gene losses and the large-scale transfer of genes to the nuclear genome. Thus the plastid genome can be regarded as a naturally evolved miniature genome, the gradual size reduction and compaction of which has provided a blueprint for the design of minimum genomes. Furthermore, because of the largely prokaryotic genome structure and gene expression machinery, the high transgene expression levels attainable in transgenic chloroplasts and the very low production costs in plant systems, the chloroplast lends itself to synthetic biology applications that are directed towards the efficient synthesis of green chemicals, biopharmaceuticals and other metabolites of commercial interest. This review describes recent progress with the engineering of plastid genomes with large constructs of foreign or synthetic DNA, and highlights the potential of the chloroplast as a model system in bottom-up and top-down synthetic biology approaches.

  6. 78 FR 77420 - Certain Oil Country Tubular Goods From the Republic of Turkey: Preliminary Negative...

    Science.gov (United States)

    2013-12-23

    ... International Trade Administration Certain Oil Country Tubular Goods From the Republic of Turkey: Preliminary... Turkey and several other countries.\\1\\ The CVD investigation and the AD investigations cover the same... Duty Investigation of Certain Oil Country Tubular Goods from the Republic of Turkey,''...

  7. 78 FR 56865 - Certain Oil Country Tubular Goods From India and Turkey: Postponement of Preliminary...

    Science.gov (United States)

    2013-09-16

    ... International Trade Administration Certain Oil Country Tubular Goods From India and Turkey: Postponement of...\\ See Certain Oil Country Tubular Goods from India and Turkey: Initiation of Countervailing Duty...) 482-3964 (India); Shane Subler at (202) 482-0189 (Turkey), AD/CVD Operations, Import...

  8. Everything you need to know about distal renal tubular acidosis in autoimmune disease

    NARCIS (Netherlands)

    T. Both (Tim); R. Zietse (Bob); E.J. Hoorn (Ewout); P.M. van Hagen (Martin); V.A.S.H. Dalm (Virgil); J.A.M. van Laar (Jan); P.L.A. van Daele (Paul)

    2014-01-01

    textabstractRenal acid-base homeostasis is a complex process, effectuated by bicarbonate reabsorption and acid secretion. Impairment of urinary acidification is called renal tubular acidosis (RTA). Distal renal tubular acidosis (dRTA) is the most common form of the RTA syndromes. Multiple pathophysi

  9. Preservation of paraspinal muscle after transmuscular approach using a tubular retractor for lumbar decompression surgery

    Directory of Open Access Journals (Sweden)

    Toshiya Tachibana, MD, PhD

    2017-09-01

    Conclusion: The preservation of paraspinal muscle was greater in patients with a tubular retractor than with the subperiosteal approach. Detaching the paraspinal muscle from the lamina may cause partial denervation of the paraspinal muscle and muscle atrophy. Therefore, the transmuscular approach using a tubular retractor may be a less invasive approach for the preservation of paraspinal muscle.

  10. VALIDATION OF SIMULATION MODELS FOR DIFFERENTLY DESIGNED HEAT-PIPE EVACUATED TUBULAR COLLECTORS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Dragsted, Janne; Furbo, Simon

    2007-01-01

    Differently designed heat-pipe evacuated tubular collectors have been investigated theoretically and experimentally. The theoretical work has included development of two TRNSYS [1] simulation models for heat-pipe evacuated tubular collectors utilizing solar radiation from all directions. One model...

  11. Dysfunctional tubular endoplasmic reticulum constitutes a pathological feature of Alzheimer's disease.

    Science.gov (United States)

    Sharoar, M G; Shi, Q; Ge, Y; He, W; Hu, X; Perry, G; Zhu, X; Yan, R

    2016-09-01

    Pathological features in Alzheimer's brains include mitochondrial dysfunction and dystrophic neurites (DNs) in areas surrounding amyloid plaques. Using a mouse model that overexpresses reticulon 3 (RTN3) and spontaneously develops age-dependent hippocampal DNs, here we report that DNs contain both RTN3 and REEPs, topologically similar proteins that can shape tubular endoplasmic reticulum (ER). Importantly, ultrastructural examinations of such DNs revealed gradual accumulation of tubular ER in axonal termini, and such abnormal tubular ER inclusion is found in areas surrounding amyloid plaques in biopsy samples from Alzheimer's disease (AD) brains. Functionally, abnormally clustered tubular ER induces enhanced mitochondrial fission in the early stages of DN formation and eventual mitochondrial degeneration at later stages. Furthermore, such DNs are abrogated when RTN3 is ablated in aging and AD mouse models. Hence, abnormally clustered tubular ER can be pathogenic in brain regions: disrupting mitochondrial integrity, inducing DNs formation and impairing cognitive function in AD and aging brains.

  12. Research on typical topologies of a tubular horizontal-gap passive magnetic levitation vibration isolator

    Directory of Open Access Journals (Sweden)

    Zhou Yiheng

    2017-01-01

    Full Text Available Magnetic levitation vibration isolators have attracted more and more attention in the field of high-precision measuring and machining equipment. In this paper, we describe a tubular horizontal-gap passive magnetic levitation vibration isolator. Four typical topologies of the tubular horizontal-gap passive magnetic levitation vibration isolator are proposed. The analytical expression of magnetic force is derived. The relationship between levitation force, force density, force ripple and major structural parameters are analysed by finite element method, which is conductive to the design and optimization of the tubular horizontal-gap passive magnetic levitation vibration isolator. The force characteristics of different topologies of the tubular horizontal-gap passive magnetic levitation vibration isolator are compared and evaluated from the aspect of force density, force ripple and manufacturability. In comparison with conventional passive magnetic levitation vibration isolators, the proposed tubular horizontal-gap passive magnetic levitation vibration isolator shows advantage in higher force density.

  13. MICAL-L1-related and unrelated mechanisms underlying elongated tubular endosomal network (ETEN) in human dendritic cells

    NARCIS (Netherlands)

    Compeer, E.B.; Boes, Marianne

    2014-01-01

    The endosomal pathway constitutes a highly dynamic intracellular transport system, which is composed of vesicular and tubular compartments. Endosomal tubules enable geometry-based discrimination between membrane and luminal content. Extended tubular endosomes were suggested to deliver a steady strea

  14. Hybrid Metaheuristics

    CERN Document Server

    2013-01-01

    The main goal of this book is to provide a state of the art of hybrid metaheuristics. The book provides a complete background that enables readers to design and implement hybrid metaheuristics to solve complex optimization problems (continuous/discrete, mono-objective/multi-objective, optimization under uncertainty) in a diverse range of application domains. Readers learn to solve large scale problems quickly and efficiently combining metaheuristics with complementary metaheuristics, mathematical programming, constraint programming and machine learning. Numerous real-world examples of problems and solutions demonstrate how hybrid metaheuristics are applied in such fields as networks, logistics and transportation, bio-medical, engineering design, scheduling.

  15. Opportunities in plant synthetic biology.

    Science.gov (United States)

    Cook, Charis; Martin, Lisa; Bastow, Ruth

    2014-05-01

    Synthetic biology is an emerging field uniting scientists from all disciplines with the aim of designing or re-designing biological processes. Initially, synthetic biology breakthroughs came from microbiology, chemistry, physics, computer science, materials science, mathematics, and engineering disciplines. A transition to multicellular systems is the next logical step for synthetic biologists and plants will provide an ideal platform for this new phase of research. This meeting report highlights some of the exciting plant synthetic biology projects, and tools and resources, presented and discussed at the 2013 GARNet workshop on plant synthetic biology.

  16. Synthetic cannabis and respiratory depression.

    Science.gov (United States)

    Jinwala, Felecia N; Gupta, Mayank

    2012-12-01

    In recent years, synthetic cannabis use has been increasing in appeal among adolescents, and its use is now at a 30 year peak among high school seniors. The constituents of synthetic cannabis are difficult to monitor, given the drug's easy accessibility. Currently, 40 U.S. states have banned the distribution and use of some known synthetic cannabinoids, and have included these drugs in the Schedule I category. The depressive respiratory effect in humans caused by synthetic cannabis inhalation has not been thoroughly investigated in the medical literature. We are the first to report, to our knowledge, two cases of self-reported synthetic cannabis use leading to respiratory depression and necessary intubation.

  17. Synthetic Completeness Proofs for Seligman-style Tableau Systems

    DEFF Research Database (Denmark)

    Jørgensen, Klaus Frovin; Blackburn, Patrick Rowan; Bolander, Thomas

    2016-01-01

    Hybrid logic is a form of modal logic which allows reference to worlds. We can think of it as ‘modal logic with labelling built into the object language’ and various forms of labelled deduction have played a central role in its proof theory. Jerry Seligman’s work [11,12] in which ‘rules involving...... Seligman-style and labelled tableaus, but our results only covered the minimal hy- brid logic; in the present paper we provide completeness results for a wider range of hybrid logics and languages. We do so by adapting the synthetic approach to tableau completeness (due to Smullyan, and widely applied...

  18. [Diagnostic difficulties in a case of constricted tubular visual field].

    Science.gov (United States)

    Dogaru, Oana-Mihaela; Rusu, Monica; Hâncu, Dacia; Horvath, Kárin

    2013-01-01

    In the paper below we present the clinical case of a 48 year old female with various symptoms associated with functional visual disturbance -constricted tubular visual fields, wich lasts from 6 years; the extensive clinical and paraclinical ophthalmological investigations ruled out the presence of an organic disorder. In the present, we suspect a diagnosis of hysteria, still uncertain, wich represented over time a big challenge in psychology and ophthalmology. The mechanisms and reasons for hysteria are still not clear and it could represent a fascinating research theme. The tunnel, spiral or star-shaped visual fields are specific findings in hysteria for patients who present visual disturbance. The question of whether or not a patient with hysterical visual impairment can or cannot "see" is still unresolved.

  19. Scalable Approach for Extrusion and Perfusion of Tubular, Heterotypic Biomaterials

    Science.gov (United States)

    Jeronimo, Mark David

    Soft material tubes are critical in the vasculature of mammalian tissues, forming networks of blood vessels and airways. Homogeneous and heterogeneous hydrogel tubes were extruded in a one-step process using a three layer microfluidic device. Co-axial cylindrical flow of crosslinking solutions and an alginate matrix is generated by a radial arrangement of microfluidic channels at the device's vertical extrusion outlet. The flow is confined and begins a sol-gel transition immediately as it extrudes at velocities upwards of 4 mm/s. This approach allows for predictive control over the dimensions of the rapidly formed tubular structures for outer diameters from 600 microm to 3 mm. A second microfluidic device hosts tube segments for controlled perfusion and pressurization using a reversible vacuum seal. On-chip tube deflection is observed and modeled as a measure of material compliance and circumferential elasticity. I anticipate applications of these devices for perfusion cell culture of cell-laden hydrogel tubes.

  20. Theoretical flow investigations of an all glass evacuated tubular collector

    DEFF Research Database (Denmark)

    Shah, Louise Jivan; Furbo, Simon

    2007-01-01

    the highest efficiency, the optimal inlet flow rate was around 0.4-1 kg/min, the flow structures in the glass tubes were relatively uninfluenced by the inlet flow rate, Generally, the results showed only small variations in the efficiencies. This indicates that the collector design is well working for most......Heat transfer and flow structures inside all glass evacuated tubular collectors for different operating conditions are investigated by means of computational fluid dynamics. The investigations are based on a collector design with horizontal tubes connected to a vertical 14 manifold channel. Three...... different tube lengths varying from 0.59 in to 1.47 in have been modelled with five different inlet mass flow rates varying from 0.05 kg/min to 10 kg/min with a constant inlet temperature of 333 K. Under these operating conditions the results showed that: the collector with the shortest tube length achieved...

  1. Amelogenesis imperfecta with distal renal tubular acidosis: A novel syndrome?

    Directory of Open Access Journals (Sweden)

    R A Misgar

    2017-01-01

    Full Text Available Amelogenesis imperfecta (AI is a heterogeneous group of inherited dental enamel defects. It has rarely been reported in association with multiorgan syndromes and metabolic disorders. The metabolic disorders that have been reported in association with AI include hypocalciuria, impaired urinary concentrating ability, and Bartter-like syndrome. In literature, only three cases of AI and distal renal tubular acidosis (dRTA have been described: two cases in adults and a solitary case in the pediatric age group. Here, we report a child with AI presenting with dRTA; to the best of our knowledge, our reported case is the only second such case in pediatric age group. Our case highlights the importance of recognizing the possibility of renal abnormalities in patients with AI as it will affect the long-term prognosis.

  2. Experimental studies of a matrix-tubular solar air collector

    Energy Technology Data Exchange (ETDEWEB)

    Plesca, M.; Varlan, P. [Moldova Technical Univ., Chisinau (Moldova, Republic of). Dept. of Heat and Gas Supply and Ventilation

    2009-06-15

    The most common types of solar air collectors (SAC) are contact-type and matrix-type collectors, with the latter being more efficient. This paper described the design and testing of a matrix-tubular flat solar air collector in the city of Chisinau, Moldova, where the outdoor climatic radiation, heat, and humidity characteristics are favorable for the efficient use of solar energy for building heating and drying applications. The amount of solar energy absorbed by a solar energy air collector depends on the level of insulation and orientation of the solar collector; the absorbance of the absorber surface; and the transmittance of the cover material. This study examined the heat transfer, efficiency, and pressure drop using copper tubes inserted perpendicular to the plane of the absorber plate. The SAC consists of a glazed insulated case, an absorber, and ducting for cold air delivery and hot air discharge. Copper tubes are inserted perpendicular to the plane of the absorber. The absorber is installed in the body of the SAC in such a way that it divides it into an upper channel and lower channel. The channel bottom is lined with aluminium foil that reflects solar radiation coming through the tubes and decreases heat loss in the solar collector. Copper tubes increase the heat exchange surface, create air turbulence and intensify heat transfer. This increases the efficiency of the solar collector. The pressure drop of the matrix-tubular solar air collector is 40 per cent lower than that of the matrix-plate collectors. 11 refs., 2 tabs., 6 figs.

  3. On milling of thin-wall conical and tubular workpieces

    Science.gov (United States)

    Tsai, Mu-Ping; Tsai, Nan-Chyuan; Yeh, Cheng-Wei

    2016-05-01

    Thin-wall tubular-geometry workpieces have been widely applied in aircraft and medical industries. However, due to the special geometry of this kind of workpieces and induced poor machinability, the desired accuracy of machining tends to be greatly degraded, no matter what type of metal-cutting task such as milling, drilling or turning is undertaken. Though numerous research reports are available that the tool path can be planned on the basis of preset surface profile before actual milling operation is performed, it is still difficult to predict the real-time surface profile errors for peripheral milling of thin-wall tubular workpieces. Instead of relying on tool path planning, this research is focused on how to real-time formulate the appropriate applied cutting torque via feedback of spindle motor current. On the other hand, a few suitable cutting conditions which are able to prevent potential break/crack of thin-wall workpieces and enhance productivity but almost retain the same cutting quality is proposed in this research. To achieve this goal, estimated surface profile error on machined parts due to deflections caused by both tool and workpiece is studied at first. Traditionally, by adjusting cutting parameters such as feed rate or cut depth, the deflection of tool or workpiece can be expected not to exceed the specified limit. Instead, an effective feedback control loop is proposed by this work for applying real-time appropriate applied cutting torque to prevent potential break/crack of the thin-wall conical workpieces. The torque estimation approach by spindle motor current feedback and the corresponding fuzzy logic controller are employed. Compared with constant cutting torque during milling operation in tradition manner, it is observed that the time consumption of milling cycle by aid of the aforesaid fuzzy logic controller is greatly shortened while the resulted cutting accuracy upon finish of workpiece can be almost retained.

  4. Tubular dysfunction after peritonectomy and chemohyperthermic treatment with cisplatin.

    Science.gov (United States)

    La Manna, Gaetano; Virzì, Salvatore; Deraco, Marcello; Capelli, Irene; Accorsi, Alma; Dalmastri, Vittorio; Comai, Giorgia; Bonomi, Serena; Grassi, Antonio; Selva, Saverio; Feliciangeli, Giorgio; Scolari, Maria; Stefoni, Sergio

    2006-01-01

    Peritoneal carcinomatosis has always been regarded as a contraindication in traditional cancer surgery treatment; however, good results have been reported by using new combined medical-surgical loco-regional techniques. Peritonectomy and chemohyperthermic perfusion with cisplatinum (CIIP) seem to play a central role in obtaining a better survival rate than with the traditional procedures, even though there is a cisplatinum nephrotoxic effect. The aim of this study was to investigate entity and type of renal injury after CIIP. Forty-two patients (12 males and 30 females) with recurrent or primary peritoneal carcinomatosis who underwent peritonectomy and cytoreductive surgery with hyperthermic intraperitoneal chemotherapy with cisplatin were enrolled. A significant worsening in renal function was observed on the third post-operative day and this condition then persisted for three months. A reduction in estimated-Glomerular Filtration Rate (e-GFR) and an alteration in the albumin:creatinine ratio proved tubular injury. On the third post-operative day after cisplatinum administration, a high toxicity peak was found following platinum free fraction excretion. Proximal tubular injury was confirmed even at the three month analysis. A significant correlation between the total protein reduction rate and the decrease in renal function was established. In relation to that, the platinum free fraction could increase because of a binding protein shortage and the nephrotoxic effect could be enhanced due to platinum accumulation within the post-operative period. This finding suggests that the higher the protein reduction is, the lower the e-GFR determination is at three months.

  5. Design of a Compact and Versatile Bench Scale Tubular Reactor

    Directory of Open Access Journals (Sweden)

    R. Prasad

    2009-06-01

    Full Text Available A compact and versatile laboratory tubular reactor has been designed and fabricated keeping in view of reducing capital cost and minimising energy consumption for gas/vapor-phase heterogeneous catalytic reactions. The reactor is consisted of two coaxial corning glass tubes with a helical coil of glass tube in between the coaxial tubes serving as vaporiser and pre-heater, the catalyst bed is in the inner tube. A schematic diagram of the reactor with detailed dimensions and working principles are described. The attractive feature of the reactor is that the vaporiser, pre-heater and fixed bed reactor are merged in a single compact unit. Thus, the unit minimises separate vaporiser and pre-heater, also avoids separate furnaces used for them and eliminate auxiliary instrumentation such as temperature controller etc. To demonstrate the system operation and illustrate the key features, catalyst screening data and the efficient collection of complete, and accurate intrinsic kinetic data are provided for oxidation of CO over copper chromite catalyst. CO oxidation is an important reaction for auto-exhaust pollution control. The suitability of the versatile nature of the reactor has been ascertained for catalytic reactions where either volatile or vaporizable feeds can be introduced to the reaction zone, e.g. oxidation of iso-octane, reduction of nitric oxide, dehydrogenation of methanol, ethanol and iso-propanol, hydrogenation of nitrobenzene to aniline, etc. Copyright (c 2009 by BCREC. All Rights reserved.[Received: 10 February 2009, Accepted: 9 May 2009][How to Cite: R. Prasad, G. Rattan. (2009. Design of a Compact and Versatile Bench Scale Tubular Reactor. Bulletin of Chemical Reaction Engineering and Catalysis, 4(1: 5-9.  doi:10.9767/bcrec.4.1.1250.5-9][How to Link/ DOI: http://dx.doi.org/10.9767/bcrec.4.1.1250.5-9

  6. Tubular Scaffold with Shape Recovery Effect for Cell Guide Applications

    Directory of Open Access Journals (Sweden)

    Kazi M. Zakir Hossain

    2015-07-01

    Full Text Available Tubular scaffolds with aligned polylactic acid (PLA fibres were fabricated for cell guide applications by immersing rolled PLA fibre mats into a polyvinyl acetate (PVAc solution to bind the mats. The PVAc solution was also mixed with up to 30 wt % β-tricalcium phosphate (β-TCP content. Cross-sectional images of the scaffold materials obtained via scanning electron microscopy (SEM revealed the aligned fibre morphology along with a significant number of voids in between the bundles of fibres. The addition of β-TCP into the scaffolds played an important role in increasing the void content from 17.1% to 25.3% for the 30 wt % β-TCP loading, which was measured via micro-CT (µCT analysis. Furthermore, µCT analyses revealed the distribution of aggregated β-TCP particles in between the various PLA fibre layers of the scaffold. The compressive modulus properties of the scaffolds increased from 66 MPa to 83 MPa and the compressive strength properties decreased from 67 MPa to 41 MPa for the 30 wt % β-TCP content scaffold. The scaffolds produced were observed to change into a soft and flexible form which demonstrated shape recovery properties after immersion in phosphate buffered saline (PBS media at 37 °C for 24 h. The cytocompatibility studies (using MG-63 human osteosarcoma cell line revealed preferential cell proliferation along the longitudinal direction of the fibres as compared to the control tissue culture plastic. The manufacturing process highlighted above reveals a simple process for inducing controlled cell alignment and varying porosity features within tubular scaffolds for potential tissue engineering applications.

  7. AM251 Suppresses Epithelial-Mesenchymal Transition of Renal Tubular Epithelial Cells

    Science.gov (United States)

    Yoshinaga, Tomoyo; Uwabe, Kenichiro; Naito, Shoichi; Higashino, Kenichi; Nakano, Toru; Numata, Yoshito

    2016-01-01

    Epithelial-mesenchymal transition (EMT) of renal tubular epithelial cells is one of the causative mechanisms of kidney fibrosis. In our study, we screened lipophilic compounds using a lipid library including approximately 200 lipids to identify those that suppressed EMT induced by a transforming growth factor (TGF)-β1 stimulus. Initial screening was performed with the immortalized HK-2 renal tubule epithelial cell line. The most promising compounds were further tested in RPTEC primary renal tubule epithelial cells. We found that the synthetic lipid AM251 suppressed two hallmark events associated with EMT, the upregulation of collagen 1A1 (COL1A1) and downregulation of E-cadherin. Though AM251 is known to act as an antagonist for the cannabinoid receptor type 1 (CB1) and an agonist for the G protein-coupled receptor 55 (GRP55), the suppression of EMT by AM251 was not mediated through either receptor. Microarray analyses revealed that AM251 inhibited induction of several EMT transcription factors such as SNAIL1, which is the key inducer of EMT, and the AP-1 transcription factors FOSB and JUNB. Activation of SMAD2/3 and p38 mitogen-activated protein kinase (MAPK) was inhibited by AM251, with greater inhibition of the latter, indicating that AM251 acted upstream of SMAD/p38 MAPK in the TGF-β signaling pathway. Our findings regarding the effects of AM251 on the TGF-β signaling pathway may inform development of a novel therapeutic agent suppressing EMT, thus preventing kidney fibrosis. PMID:27936102

  8. AM251 Suppresses Epithelial-Mesenchymal Transition of Renal Tubular Epithelial Cells.

    Science.gov (United States)

    Yoshinaga, Tomoyo; Uwabe, Kenichiro; Naito, Shoichi; Higashino, Kenichi; Nakano, Toru; Numata, Yoshito; Kihara, Akio

    2016-01-01

    Epithelial-mesenchymal transition (EMT) of renal tubular epithelial cells is one of the causative mechanisms of kidney fibrosis. In our study, we screened lipophilic compounds using a lipid library including approximately 200 lipids to identify those that suppressed EMT induced by a transforming growth factor (TGF)-β1 stimulus. Initial screening was performed with the immortalized HK-2 renal tubule epithelial cell line. The most promising compounds were further tested in RPTEC primary renal tubule epithelial cells. We found that the synthetic lipid AM251 suppressed two hallmark events associated with EMT, the upregulation of collagen 1A1 (COL1A1) and downregulation of E-cadherin. Though AM251 is known to act as an antagonist for the cannabinoid receptor type 1 (CB1) and an agonist for the G protein-coupled receptor 55 (GRP55), the suppression of EMT by AM251 was not mediated through either receptor. Microarray analyses revealed that AM251 inhibited induction of several EMT transcription factors such as SNAIL1, which is the key inducer of EMT, and the AP-1 transcription factors FOSB and JUNB. Activation of SMAD2/3 and p38 mitogen-activated protein kinase (MAPK) was inhibited by AM251, with greater inhibition of the latter, indicating that AM251 acted upstream of SMAD/p38 MAPK in the TGF-β signaling pathway. Our findings regarding the effects of AM251 on the TGF-β signaling pathway may inform development of a novel therapeutic agent suppressing EMT, thus preventing kidney fibrosis.

  9. Hybrid intermediaries

    OpenAIRE

    Cetorelli, Nicola

    2014-01-01

    I introduce the concept of hybrid intermediaries: financial conglomerates that control a multiplicity of entity types active in the "assembly line" process of modern financial intermediation, a system that has become known as shadow banking. The complex bank holding companies of today are the best example of hybrid intermediaries, but I argue that financial firms from the "nonbank" space can just as easily evolve into conglomerates with similar organizational structure, thus acquiring the cap...

  10. Hybrid composites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2009-04-01

    Full Text Available effect was observed for the elongation at break of the hybrid composites. The impact strength of the hybrid composites increased with the addition of glass fibres. The tensile and impact properties of thermoplastic natural rubber reinforced short... panels made from conventional structural materials. Figure 3 illustrates the performance of cellular biocomposite panels against conventional systems used for building and residential construction, namely a pre- cast pre-stressed hollow core concrete...

  11. Biopolymers Versus Synthetic Polymers

    Directory of Open Access Journals (Sweden)

    Florentina Adriana Cziple

    2008-10-01

    Full Text Available This paper present an overview of important synthetic and natural polymers with emphasis on polymer structure, the chemistry of polymer formation. an introduction to polymer characterization. The biodegradation process can take place aerobically and anaerobically with or without the presence of light. These factors allow for biodegradation even in landfill conditions which are normally inconducive to any degradation. The sheeting used to make these packages differs significantly from other “degradable plastics” in the market as it does not attempt to replace the current popular materials but instead enhances them by rendering them biodegradable.

  12. CASH vs. SYNTHETIC CDOs

    Directory of Open Access Journals (Sweden)

    Silviu Eduard Dinca

    2015-12-01

    Full Text Available During the past few years, in the recent post-crisis aftermath, global asset managers are constantly searching new ways to optimize their investment portfolios while financial and banking institutions around the world are exploring new alternatives to better secure their financing and refinancing demands altogether with the enhancement of their risk management capabilities. We will exhibit herewith a comparison between the true-sale and synthetic CDO securitizations as financial markets-based funding, investment and risks mitigation techniques, highlighting certain key structuring and implementation specifics on each of them.

  13. Comparative Election Forecasting: Further Insights from Synthetic Models

    OpenAIRE

    Michael S. Lewis-Beck; Dassonneville, Ruth

    2015-01-01

    As an enterprise, election forecasting has spread and grown. Initial work began in the 1980s in the United States, eventually travelling to Western Europe, where it finds a current outlet in the most of the region’s democracies. However, that work has been confined to traditional approaches – statistical modeling or poll-watching. We import a new approach, which we call synthetic modeling. These forecasts come from hybrid models blending structural knowledge with contemporary p...

  14. Synthetic collective intelligence.

    Science.gov (United States)

    Solé, Ricard; Amor, Daniel R; Duran-Nebreda, Salva; Conde-Pueyo, Núria; Carbonell-Ballestero, Max; Montañez, Raúl

    2016-10-01

    Intelligent systems have emerged in our biosphere in different contexts and achieving different levels of complexity. The requirement of communication in a social context has been in all cases a determinant. The human brain, probably co-evolving with language, is an exceedingly successful example. Similarly, social insects complex collective decisions emerge from information exchanges between many agents. The difference is that such processing is obtained out of a limited individual cognitive power. Computational models and embodied versions using non-living systems, particularly involving robot swarms, have been used to explore the potentiality of collective intelligence. Here we suggest a novel approach to the problem grounded in the genetic engineering of unicellular systems, which can be modified in order to interact, store memories or adapt to external stimuli in collective ways. What we label as Synthetic Swarm Intelligence defines a parallel approach to the evolution of computation and swarm intelligence and allows to explore potential embodied scenarios for decision making at the microscale. Here, we consider several relevant examples of collective intelligence and their synthetic organism counterparts.

  15. Freedom and Responsibility in Synthetic Genomics: The Synthetic Yeast Project

    OpenAIRE

    Sliva, Anna; Yang, Huanming; Boeke, Jef D.; Debra J. H. Mathews

    2015-01-01

    First introduced in 2011, the Synthetic Yeast Genome (Sc2.0) Project is a large international synthetic genomics project that will culminate in the first eukaryotic cell (Saccharomyces cerevisiae) with a fully synthetic genome. With collaborators from across the globe and from a range of institutions spanning from do-it-yourself biology (DIYbio) to commercial enterprises, it is important that all scientists working on this project are cognizant of the ethical and policy issues associated with...

  16. Nephrotic syndrome and multiple tubular defects in children: an early sign of focal segmental glomerulosclerosis.

    Science.gov (United States)

    McVicar, M; Exeni, R; Susin, M

    1980-12-01

    The nephrotic syndrome is rarely associated with renal tubular defects, and the combination has been reported only in association with advanced renal insufficiency. We report here five children with nephrotic syndrome and multiple tubular defects which evolved when glomular filtration rate ranged between 56 and 90 ml/minute/1.73 m2. The tubular defects were first noted at 3, 4, 4, 7, and 22 months after the onset of the nephrotic syndrome, and renal glycosuria was the first sign in all five children. Glycosuria was intermittent in three patients, constant in two, and ceased with loss of kidney function. Four patients had hyperaminoaciduria and renal tubular acidosis (two of four tested had distal renal tubular acidosis). Three patients had decreased tubular reabsorption of phosphorus and defective maximum concentrating capacity. All five had focal segmental glomerulosclerosis proven by renal biopsy. Over a follow-up period of seven years, all of the children have developed advanced renal insufficiency, four of the five have required dialysis or transplantation within 21 to 72 months after onset, and one has stabilized renal function at 35 ml/minute/1.73 m2. The one patient receiving a kidney transplant has had recurrence of focal segmental glomerulosclerosis in the transplanted kidney and became nephrotic with three subsequent transplants. Our experience suggests that the nephrotic syndrome associated with tubular defects in children forms a subgroup of focal segmental glomerulosclerosis, with rapid progression to renal insufficiency and the potential for recurrence of the lesion in the transplanted kidney.

  17. Assessment of the place of tubular reabsorption of phosphorus in the diagnosis of osteopenia of prematurity

    Science.gov (United States)

    Acar, Duygu Besnili; Kavuncuoğlu, Sultan; Çetinkaya, Merih; Petmezci, Ercüment; Dursun, Mesut; Korkmaz, Orhan; Altuncu, Emel Kayrak

    2015-01-01

    Aim: In this study, we aimed to investigate the utility of tubular reabsorption of phosphorus in the diagnosis of osteopenia of prematurity in addition to biochemical markers. Materials and Method: Premature babies with a gestational age of ≤32 weeks and/or a birth weight of ≤1 500 g who were hospitalized in the neonatal intensive care unit between June 2009 and March 2011 were included in the study. These babies were evaluated at the 40th gestational week and serum calcium, phosphorus, alkaline phosphatase, urea, creatinine, urinary calcium and phosphorus levels were measured and tubular reabsorption of phosphorus was determined. The subjects who had bone graphy findings and/or an alkaline phosphatase level of >400IU/L and a phosphorus value of 499 IU were compared with the newborns who were found to have a tubular reabsorption of phosphorus of ≥%95 for the objective of evaluating the specificity and sensitivity of tubular reabsorption of phosphorus, the sensitivity, specificity, positive predictive value and negative predictive value of tubular reabsorption of phosphorus in the diagnosis of osteopenia were found to be 27%, 82%, 17% and 89%, respectively. When the osteopenic and non-osteopenic patients were compared in terms of the levels of tubular reabsorption of phosphorus, no statistically significant difference was found. Conclusions: It was thought that it was not appropriate to use tubular reabsorption of phosphorus alone in the diagnosis of osteopenia of prematurity. PMID:26078696

  18. Strap grid tubular plate—a new positive plate for lead-acid batteries. Processes of residual sulphation of the positive plate

    Science.gov (United States)

    Pavlov, D.; Papazov, G.; Monahov, B.

    For almost a century now the tubular plate design has been based on cylindrical tubes and spines. The contact surface between the positive active mass (PAM) and the spine is small, which results in high polarisation of the plate at high discharge currents and low power output of the cell. In an attempt to eliminate these disadvantages, the shape of the tubes has been changed to flattened elliptic and the spines have been replaced by strap grids. The thickness of this new type of tubular plate, strap grid tubular plate (SGTP), is between 3 and 5 mm. Batteries with tubular plates of the new design (SGTP batteries) can be used in electric vehicle (EV) and photovoltaic (PV) system applications. This paper presents results of SGTP battery tests according to the European standards for EV, hybrid electric vehicle (HEV) and photovoltaic (PV) system batteries. SGTP batteries have a cycle life of 1000 ECE-15-EV cycles, 6000 ECE-HEV cycles and more than eight gross PV cycles. The optimum battery charge algorithm for VRLA batteries with strap grid tubular plates has been established and the mechanism of disintegration of the positive active mass has been disclosed. The following phenomena are responsible for the decline in capacity of the positive plates. First, when the PAM is built up of globules adhering closely to each other, a strong skeleton with thick aggregates (branches) with a membrane surface is formed. The surface layer of the branches impedes the access of H 2O and H 2SO 4 to their interior thus reducing the utilisation of the PAM. Besides, internal stresses are created in the aggregates, which cause them to crack. Secondly, when the PAM is built up of individual agglomerates with micropores in between, a porous mass with large surface is formed. The tubes keep the aggregates together and prolong the cycle life of the battery. During discharge, the contacts between the aggregates weaken and the capacity declines. Third, during discharge, the H 2SO 4 concentration

  19. Kidney specific protein-positive cells derived from embryonic stem cells reproduce tubular structures in vitro and differentiate into renal tubular cells.

    Science.gov (United States)

    Morizane, Ryuji; Monkawa, Toshiaki; Fujii, Shizuka; Yamaguchi, Shintaro; Homma, Koichiro; Matsuzaki, Yumi; Okano, Hideyuki; Itoh, Hiroshi

    2014-01-01

    Embryonic stem cells and induced pluripotent stem cells have the ability to differentiate into various organs and tissues, and are regarded as new tools for the elucidation of disease mechanisms as well as sources for regenerative therapies. However, a method of inducing organ-specific cells from pluripotent stem cells is urgently needed. Although many scientists have been developing methods to induce various organ-specific cells from pluripotent stem cells, renal lineage cells have yet to be induced in vitro because of the complexity of kidney structures and the diversity of kidney-component cells. Here, we describe a method of inducing renal tubular cells from mouse embryonic stem cells via the cell purification of kidney specific protein (KSP)-positive cells using an anti-KSP antibody. The global gene expression profiles of KSP-positive cells derived from ES cells exhibited characteristics similar to those of cells in the developing kidney, and KSP-positive cells had the capacity to form tubular structures resembling renal tubular cells when grown in a 3D culture in Matrigel. Moreover, our results indicated that KSP-positive cells acquired the characteristics of each segment of renal tubular cells through tubular formation when stimulated with Wnt4. This method is an important step toward kidney disease research using pluripotent stem cells, and the development of kidney regeneration therapies.

  20. Hydrothermal growth of NiSe 2 tubular microcrystals assisted by PVA

    Science.gov (United States)

    Fan, Hai; Zhang, Maofeng; Zhang, Xianwen; Qian, Yitai

    2009-10-01

    NiSe 2 tubular microcrystals assembled of nanoparticles have been prepared via a hydrothermal method in an ethanolamine and water mixed solution assisted by polyvinyl alcohol (PVA). The prepared tubular crystals with hexagonal structure are composed of nanoparticles with average diameter of 30 nm. It was found that the phase of the products could be adjusted by the molar ratio of the reactants (Ni/Se), and the morphology of the products could be greatly influenced by the quantity of surfactant PVA. Based on the experimental results, the possible formation mechanism of NiSe 2 tubular microcrystals is also discussed.

  1. Tissue Harmonic Synthetic Aperture Imaging

    DEFF Research Database (Denmark)

    Rasmussen, Joachim

    The main purpose of this PhD project is to develop an ultrasonic method for tissue harmonic synthetic aperture imaging. The motivation is to advance the field of synthetic aperture imaging in ultrasound, which has shown great potentials in the clinic. Suggestions for synthetic aperture tissue...... system complexity compared to conventional synthetic aperture techniques. In this project, SASB is sought combined with a pulse inversion technique for 2nd harmonic tissue harmonic imaging. The advantages in tissue harmonic imaging (THI) are expected to further improve the image quality of SASB...... harmonic techniques have been made, but none of these methods have so far been applicable for in-vivo imaging. The basis of this project is a synthetic aperture technique known as synthetic aperture sequential beamforming (SASB). The technique utilizes a two step beamforming approach to drastically reduce...

  2. Synthetic biology and genetic causation.

    Science.gov (United States)

    Oftedal, Gry; Parkkinen, Veli-Pekka

    2013-06-01

    Synthetic biology research is often described in terms of programming cells through the introduction of synthetic genes. Genetic material is seemingly attributed with a high level of causal responsibility. We discuss genetic causation in synthetic biology and distinguish three gene concepts differing in their assumptions of genetic control. We argue that synthetic biology generally employs a difference-making approach to establishing genetic causes, and that this approach does not commit to a specific notion of genetic program or genetic control. Still, we suggest that a strong program concept of genetic material can be used as a successful heuristic in certain areas of synthetic biology. Its application requires control of causal context, and may stand in need of a modular decomposition of the target system. We relate different modularity concepts to the discussion of genetic causation and point to possible advantages of and important limitations to seeking modularity in synthetic biology systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Space Synthetic Biology Project

    Science.gov (United States)

    Howard, David; Roman, Monsi; Mansell, James (Matt)

    2015-01-01

    Synthetic biology is an effort to make genetic engineering more useful by standardizing sections of genetic code. By standardizing genetic components, biological engineering will become much more similar to traditional fields of engineering, in which well-defined components and subsystems are readily available in markets. Specifications of the behavior of those components and subsystems can be used to model a system which incorporates them. Then, the behavior of the novel system can be simulated and optimized. Finally, the components and subsystems can be purchased and assembled to create the optimized system, which most often will exhibit behavior similar to that indicated by the model. The Space Synthetic Biology project began in 2012 as a multi-Center effort. The purpose of this project was to harness Synthetic Biology principals to enable NASA's missions. A central target for application was to Environmental Control & Life Support (ECLS). Engineers from NASA Marshall Space Flight Center's (MSFC's) ECLS Systems Development Branch (ES62) were brought into the project to contribute expertise in operational ECLS systems. Project lead scientists chose to pursue the development of bioelectrochemical technologies to spacecraft life support. Therefore, the ECLS element of the project became essentially an effort to develop a bioelectrochemical ECLS subsystem. Bioelectrochemical systems exploit the ability of many microorganisms to drive their metabolisms by direct or indirect utilization of electrical potential gradients. Whereas many microorganisms are capable of deriving the energy required for the processes of interest (such as carbon dioxide (CO2) fixation) from sunlight, it is believed that subsystems utilizing electrotrophs will exhibit smaller mass, volume, and power requirements than those that derive their energy from sunlight. In the first 2 years of the project, MSFC personnel conducted modeling, simulation, and conceptual design efforts to assist the

  4. Life after the synthetic cell

    DEFF Research Database (Denmark)

    Rasmussen, Steen

    2010-01-01

    Nature asked eight synthetic-biology experts about the implications for science and society of the “synthetic cell” made by the J. Craig Venter Institute (JCVI). The institute's team assembled, modified and implanted a synthesized genome into a DNA-free bacterial shell to make a self-replicating ......Nature asked eight synthetic-biology experts about the implications for science and society of the “synthetic cell” made by the J. Craig Venter Institute (JCVI). The institute's team assembled, modified and implanted a synthesized genome into a DNA-free bacterial shell to make a self...

  5. Synthetic biology and occupational risk.

    Science.gov (United States)

    Howard, John; Murashov, Vladimir; Schulte, Paul

    2017-03-01

    Synthetic biology is an emerging interdisciplinary field of biotechnology that involves applying the principles of engineering and chemical design to biological systems. Biosafety professionals have done an excellent job in addressing research laboratory safety as synthetic biology and gene editing have emerged from the larger field of biotechnology. Despite these efforts, risks posed by synthetic biology are of increasing concern as research procedures scale up to industrial processes in the larger bioeconomy. A greater number and variety of workers will be exposed to commercial synthetic biology risks in the future, including risks to a variety of workers from the use of lentiviral vectors as gene transfer devices. There is a need to review and enhance current protection measures in the field of synthetic biology, whether in experimental laboratories where new advances are being researched, in health care settings where treatments using viral vectors as gene delivery systems are increasingly being used, or in the industrial bioeconomy. Enhanced worker protection measures should include increased injury and illness surveillance of the synthetic biology workforce; proactive risk assessment and management of synthetic biology products; research on the relative effectiveness of extrinsic and intrinsic biocontainment methods; specific safety guidance for synthetic biology industrial processes; determination of appropriate medical mitigation measures for lentiviral vector exposure incidents; and greater awareness and involvement in synthetic biology safety by the general occupational safety and health community as well as by government occupational safety and health research and regulatory agencies.

  6. Life after the synthetic cell

    DEFF Research Database (Denmark)

    Rasmussen, Steen

    2010-01-01

    Nature asked eight synthetic-biology experts about the implications for science and society of the “synthetic cell” made by the J. Craig Venter Institute (JCVI). The institute's team assembled, modified and implanted a synthesized genome into a DNA-free bacterial shell to make a self-replicating ......Nature asked eight synthetic-biology experts about the implications for science and society of the “synthetic cell” made by the J. Craig Venter Institute (JCVI). The institute's team assembled, modified and implanted a synthesized genome into a DNA-free bacterial shell to make a self...

  7. Synthetic Aperture Ultrasound Imaging

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Nikolov, Svetoslav; Gammelmark, Kim Løkke

    2006-01-01

    The paper describes the use of synthetic aperture (SA) imaging in medical ultrasound. SA imaging is a radical break with today's commercial systems, where the image is acquired sequentially one image line at a time. This puts a strict limit on the frame rate and the possibility of acquiring...... a sufficient amount of data for high precision flow estimation. These constrictions can be lifted by employing SA imaging. Here data is acquired simultaneously from all directions over a number of emissions, and the full image can be reconstructed from this data. The talk will demonstrate the many benefits...... of SA imaging. Due to the complete data set, it is possible to have both dynamic transmit and receive focusing to improve contrast and resolution. It is also possible to improve penetration depth by employing codes during ultrasound transmission. Data sets for vector flow imaging can be acquired using...

  8. Computational synthetic geometry

    CERN Document Server

    Bokowski, Jürgen

    1989-01-01

    Computational synthetic geometry deals with methods for realizing abstract geometric objects in concrete vector spaces. This research monograph considers a large class of problems from convexity and discrete geometry including constructing convex polytopes from simplicial complexes, vector geometries from incidence structures and hyperplane arrangements from oriented matroids. It turns out that algorithms for these constructions exist if and only if arbitrary polynomial equations are decidable with respect to the underlying field. Besides such complexity theorems a variety of symbolic algorithms are discussed, and the methods are applied to obtain new mathematical results on convex polytopes, projective configurations and the combinatorics of Grassmann varieties. Finally algebraic varieties characterizing matroids and oriented matroids are introduced providing a new basis for applying computer algebra methods in this field. The necessary background knowledge is reviewed briefly. The text is accessible to stud...

  9. Transionospheric synthetic aperture imaging

    CERN Document Server

    Gilman, Mikhail; Tsynkov, Semyon

    2017-01-01

    This landmark monograph presents the most recent mathematical developments in the analysis of ionospheric distortions of SAR images and offers innovative new strategies for their mitigation. As a prerequisite to addressing these topics, the book also discusses the radar ambiguity theory as it applies to synthetic aperture imaging and the propagation of radio waves through the ionospheric plasma, including the anisotropic and turbulent cases. In addition, it covers a host of related subjects, such as the mathematical modeling of extended radar targets (as opposed to point-wise targets) and the scattering of radio waves off those targets, as well as the theoretical analysis of the start-stop approximation, which is used routinely in SAR signal processing but often without proper justification. The mathematics in this volume is clean and rigorous – no assumptions are hidden or ambiguously stated. The resulting work is truly interdisciplinary, providing both a comprehensive and thorough exposition of the field,...

  10. Variation and Synthetic Speech

    CERN Document Server

    Miller, C; Massey, N; Miller, Corey; Karaali, Orhan; Massey, Noel

    1997-01-01

    We describe the approach to linguistic variation taken by the Motorola speech synthesizer. A pan-dialectal pronunciation dictionary is described, which serves as the training data for a neural network based letter-to-sound converter. Subsequent to dictionary retrieval or letter-to-sound generation, pronunciations are submitted a neural network based postlexical module. The postlexical module has been trained on aligned dictionary pronunciations and hand-labeled narrow phonetic transcriptions. This architecture permits the learning of individual postlexical variation, and can be retrained for each speaker whose voice is being modeled for synthesis. Learning variation in this way can result in greater naturalness for the synthetic speech that is produced by the system.

  11. Synthetic Aperture Compound Imaging

    DEFF Research Database (Denmark)

    Hansen, Jens Munk

    Medical ultrasound imaging is used for many purposes, e.g. for localizing and classifying cysts, lesions, and other processes. Almost any mass is first observed using B-mode imaging and later classified using e.g. color flow, strain, or attenuation imaging. It is therefore important that the B....... The method is investigated using simulations and through measurements using both phased array and convex array transducers. The images all show an improved contrast compared to images without compounding, and by construction, imaging using an improved frame rate is possible. Using a phased array transducer...... and the limiting factor is the amount of memory IO resources available. An equally high demand for memory throughput is found in the computer gaming industry, where a large part of the processing takes place on the graphics processing unit (GPU). Using the GPU, a framework for synthetic aperture imaging...

  12. Etiopathology of chronic tubular, glomerular and renovascular nephropathies: Clinical implications

    Directory of Open Access Journals (Sweden)

    Ortiz Alberto

    2011-01-01

    Full Text Available Abstract Chronic kidney disease (CKD comprises a group of pathologies in which the renal excretory function is chronically compromised. Most, but not all, forms of CKD are progressive and irreversible, pathological syndromes that start silently (i.e. no functional alterations are evident, continue through renal dysfunction and ends up in renal failure. At this point, kidney transplant or dialysis (renal replacement therapy, RRT becomes necessary to prevent death derived from the inability of the kidneys to cleanse the blood and achieve hydroelectrolytic balance. Worldwide, nearly 1.5 million people need RRT, and the incidence of CKD has increased significantly over the last decades. Diabetes and hypertension are among the leading causes of end stage renal disease, although autoimmunity, renal atherosclerosis, certain infections, drugs and toxins, obstruction of the urinary tract, genetic alterations, and other insults may initiate the disease by damaging the glomerular, tubular, vascular or interstitial compartments of the kidneys. In all cases, CKD eventually compromises all these structures and gives rise to a similar phenotype regardless of etiology. This review describes with an integrative approach the pathophysiological process of tubulointerstitial, glomerular and renovascular diseases, and makes emphasis on the key cellular and molecular events involved. It further analyses the key mechanisms leading to a merging phenotype and pathophysiological scenario as etiologically distinct diseases progress. Finally clinical implications and future experimental and therapeutic perspectives are discussed.

  13. The thermal decomposition of methane in a tubular reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Atsushi; Steinberg, M.

    1992-01-01

    The reaction rate of methane decomposition using a tubular reactor having a 1 inch inside diameter with an 8 foot long heated zone was investigated in the temperature range of 700 to 900 C with pressures ranging from 28.2 to 56.1 atm. Representing the rate by a conventional model, {minus}dC{sub CH4}/dt= k1 C{sub CH4} {minus}k2 C{sub H2}{sup 2}, the rate constant k1 for methane decomposition was determined. The activation energy, 31.3 kcal/mol, calculated by an Arrhenius Plot was lower than for previously published results for methane decomposition. This result indicates that submicron particles found in the reactor adhere to the inside of the reactor and these submicron high surface area carbon particles tend to catalyze the methane decomposition. The rate constant has been found to be approximately constant at 900 C with pressure range cited above. The rate of methane decomposition increases with methane partial pressure in first-order. The rate of the methane decomposition is favored by higher temperatures and pressures while the thermochemical equilibrium of methane decomposition is favored by lower pressures. 8 refs., 7 figs., 2 tabs.

  14. A review of the ultimate strength of tubular framed structures

    Energy Technology Data Exchange (ETDEWEB)

    Bolt, H.M.; Billington, C.J.; Ward, J.K.

    1996-10-01

    This review of the ultimate strength of tubular framed structures has been prepared for the Health and Safety Executive (HSE) by Billington Osborne-Moss Engineering Limited (BOMEL). A numerical capability to predict the nonlinear response of jacket structures has been developed over the last decade in parallel with experimental investigations. It is now being applied to assure the continued integrity of installations beyond the design event in circumstances of extreme environmental loading or damage. A recent investigation has confirmed that an extreme event static pushover analysis generally suffices to demonstrate a structure`s resistance to the cyclic loading of the full storm. This report draws together the results from published investigations and identifies key factors contributing to system reserve. It is shown that bracing configurations and relative member properties are important influences. From the work presented, it is demonstrated that many jacket analyses embody simplifying assumptions, and features such as loading asymmetry, joint nonlinearity, foundation interactions, global deflection criteria etc, are neglected. Specific examples highlighted in the review illustrate their potential importance and systematic sensitivity evaluations are therefore recommended. (UK)

  15. Standing wave brass-PZT square tubular ultrasonic motor.

    Science.gov (United States)

    Park, Soonho; He, Siyuan

    2012-09-01

    This paper reports a standing wave brass-PZT tubular ultrasonic motor. The motor is composed of a brass square tube with two teeth on each tube end. Four PZT plates are attached to the outside walls of the brass tube. The motor requires only one driving signal to excite vibration in a single bending mode to generate reciprocating diagonal trajectories of teeth on the brass tube ends, which drive the motor to rotate. Bi-directional rotation is achieved by exciting different pairs of PZT plates to switch the bending vibration direction. Through using the brass-PZT tube structure, the motor can take high magnitude vibration to achieve a high output power in comparison to PZT tube based ultrasonic motors. Prototypes are fabricated and tested. The dimension of the brass-PZT tube is 3.975mm×3.975mm×16mm. Measured performance is a no-load speed of >1000RPM, a stall torque of 370μNm and a maximum output power of 16 mW when a sinusoidal driving voltage of 50V is applied. The working frequencies of the motor are 46,050Hz (clockwise) and 46,200Hz (counter-clockwise).

  16. Design and characterization of a hyperelastic tubular soft composite.

    Science.gov (United States)

    Shaheen, Robert; Doumit, Marc; Helal, Alexander

    2017-11-01

    Research in the field of human mobility assistive devices, aiming to reduce the metabolic cost of daily activities, is seeing the benefits of the exclusive use of passive actuators to store and release energy during the gait cycle. Current devices commonly employ either mechanical springs or Pneumatic Artificial Muscles as the primary method of passive actuation. The Pneumatic Artificial Muscle has proven to be a superior actuation choice for these devices, when compared to its alternatives. However, challenges regarding muscle pressure loss and limited elongation potential have been identified. This paper presents a hyperelastic tubular Soft Composite that replicates the distinctive mechanical behaviour of the Pneumatic Artificial Muscle without the need for internal pressurization. The proposed Soft Composite solution is achieved by impregnating a prefabricated polyethylene terephthalate braided sleeve, held at a high initial fibre angle, with a silicone prepolymer. A comprehensive experimental evaluation is achieved on numerous prototypes for a variety of customizable design parameters including: the initial fibre angle, the silicone stiffness, and the braided sleeve style. This research has successfully developed, tested, and validated a novel Soft Composite that can achieve the desired nonlinear stiffness and elongation potential for optimal use as passive actuation in human mobility assistive devices. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Steady State Response Analysis of a Tubular Piezoelectric Print Head.

    Science.gov (United States)

    Chang, Jiaqing; Liu, Yaxin; Huang, Bo

    2016-01-12

    In recent years, inkjet technology has played an important role in industrial materials printing and various sensors fabrication, but the mechanisms of the inkjet print head should be researched more elaborately. The steady state deformation analysis of a tubular piezoelectric print head, which can be classified as a plane strain problem because the radii of the tubes are considerably smaller than the lengths, is discussed in this paper. The geometric structure and the boundary conditions are all axisymmetric, so a one-dimensional mathematical model is constructed. By solving the model, the deformation field and stress field, as well as the electric potential distribution of the piezoelectric tube and glass tube, are obtained. The results show that the deformations are on the nanometer scale, the hoop stress is larger than the radial stress on the whole, and the potential is not linearly distributed along the radial direction. An experiment is designed to validate these computations. A discussion of the effect of the tubes' thicknesses on the system deformation status is provided.

  18. Bioprocess kinetics in a horizontal rotating tubular bioreactor.

    Science.gov (United States)

    Ivancić, M; Santek, B; Novak, S; Horvat, P; Marić, V

    2004-04-01

    A horizontal rotating tubular bioreactor (HRTB) is a plug flow bioreactor whose interior is provided with O-ring-shaped partition walls that serve as carriers for microbial biomass. During this investigation, microbial biomass was grown in suspension and on the bioreactor inner surface as a microbial biofilm with average mass that was considerably higher than suspended biomass. The dynamics of bioprocess in HRTB was studied by different combinations of process parameters (bioreactor rotation speed and mean residence time) and it was monitored by withdrawing the samples from five positions along the bioreactor. During this investigation it was also observed that mean residence time had a more pronounced effect on the bioprocess dynamics than bioreactor rotation speed. For the description of bioprocess kinetics in HRTB an unstructured kinetic model was established that defines biomass growth, product formations and substrate consumption rate by using a modified Monod (Levenspiel) model. This kinetic model defines changes in suspension and in microbial biofilm, and it shows relatively good agreement with experimental data.

  19. Microbial acetate oxidation in horizontal rotating tubular bioreactor

    Indian Academy of Sciences (India)

    A Slavica; B Šantek; S Novak; V Marić

    2004-06-01

    The aim of this work was to investigate the possibility of conducting a continuous aerobic bioprocess in a horizontal rotating tubular bioreactor (HRTB). Aerobic oxidation of acetate by the action of a mixed microbial culture was chosen as a model process. The microbial culture was not only grown in a suspension but also in the form of a biofilm on the interior surface of HRTB. Efficiency of the bioprocess was monitored by determination of the acetate concentration and chemical oxygen demand (COD). While acetate inlet concentration and feeding rate influenced efficiency of acetate oxidation, the bioreactor rotation speed did not influence the bioprocess dynamics significantly. Gradients of acetate concentration and pH along HRTB were more pronounced at lower feeding rates. Volumetric load of acetate was proved to be the most significant parameter. High volumetric loads (above 2 g acetate l–1 h–1) gave poor acetate oxidation efficiency (only 17 to 50%). When the volumetric load was in the range of 0.60–1.75 g acetate l–1 h–1, acetate oxidation efficiency was 50–75%. At lower volumetric loads (0.14–0.58 g acetate l–1 h–1), complete acetate consumption was achieved. On the basis of the obtained results, it can be concluded that HRTB is suitable for conducting aerobic continuous bioprocesses.

  20. Mechanism of hydrogen-induced intergranular cracking of tubular steels

    Institute of Scientific and Technical Information of China (English)

    乔利杰; 褚武扬; 于广华; 程以环

    1996-01-01

    Hydrogen could be enriched on grain boundaries by stress induction and other traps.The enriched hydrogen facilitated emission and movement of dislocations and lowered plastic work.Consequently,fracture occurred easily along grain boundary.A normalized threshold value of hydrogen-induced cracking (HIC) along grain boundary is given as (KIH/KIC)2=1-0.162×10-3 βHCc(H)GH/(2γs-γb-0.16×103∑β CiGi),where βH and βi are the enrichment factors of hydrogen and other elements on grain boundaries,respectively;Cc(H) is hydrogen concentration induced by stress;C,is the average concentration of an element in the steel;GH and Gi are factors of fracture work along grain boundary with hydrogen and other elements,and γs and γb are surface free energy and grain boundary energy of Fe.For tubular steel,the calculated KH/KIC is 0.23 while the determined value is 0.26.The theoretical threshold value is well consistent with the experimental one.

  1. Ammonia-water absorption in vertical tubular absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Seara, Jose; Sieres, Jaime; Rodriguez, Cristobal; Vazquez, Manuel [Area de Maquinas y Motores Termicos, Escuela Tecnica Superior de Ingenieros Industriales, Campus Lagoas-Marcosende, No 9, 36200 Vigo (Spain)

    2005-03-01

    This paper presents a detailed analysis of the heat and mass transfer processes during the absorption of ammonia into water in a co-current vertical tubular absorber. The absorber configuration is of the shell and tubes type. The absorption process progresses as the vapour and liquid contact inside the tubes. Water is used as the absorber cooling medium. A differential mathematical model has been developed on the basis of mass and energy balances and heat and mass transfer equations, in order to provide further understanding of the absorber behaviour. The model takes into account separately for the churn, slug and bubbly flow patterns experimentally forecasted in this type of absorption processes inside vertical tubes and considers the simultaneous heat and mass transfer processes in both liquid and vapour phases, as well as heat transfer to the cooling medium. The model equations have been solved using the finite-difference method. Results obtained for specific data are depicted to show local values of the most important variables all along the absorber length. Parametric analyses have been performed to show the influence of design parameters and operating conditions on the absorber performance. The effect of the heat and mass transfer coefficients has also been evaluated. (authors)

  2. HIGH-TEMPERATURE TUBULAR SOLID OXIDE FUEL CELL GENERATOR DEVELOPMENT

    Energy Technology Data Exchange (ETDEWEB)

    S.E. Veyo

    1998-09-01

    During the Westinghouse/USDOE Cooperative Agreement period of November 1, 1990 through November 30, 1997, the Westinghouse solid oxide fuel cell has evolved from a 16 mm diameter, 50 cm length cell with a peak power of 1.27 watts/cm to the 22 mm diameter, 150 cm length dimensions of today's commercial prototype cell with a peak power of 1.40 watts/cm. Accompanying the increase in size and power density was the elimination of an expensive EVD step in the manufacturing process. Demonstrated performance of Westinghouse's tubular SOFC includes a lifetime cell test which ran for a period in excess of 69,000 hours, and a fully integrated 25 kWe-class system field test which operated for over 13,000 hours at 90% availability with less than 2% performance degradation over the entire period. Concluding the agreement period, a 100 kW SOFC system successfully passed its factory acceptance test in October 1997 and was delivered in November to its demonstration site in Westervoort, The Netherlands.

  3. A tubular dielectric elastomer actuator: Fabrication, characterization and active vibration isolation

    DEFF Research Database (Denmark)

    Sarban, R.; Jones, R. W.; Mace, B. R.;

    2011-01-01

    This contribution reviews the fabrication, characterization and active vibration isolation performance of a core-free rolled tubular dielectric elastomer (DE) actuator, which has been designed and developed by Danfoss PolyPower A/S. PolyPower DE material, PolyPower (TM), is produced in thin sheets...... of 80 mu m thickness with corrugated metallic electrodes on both sides. Tubular actuators are manufactured by rolling the DE sheets in a cylindrical shape. The electromechanical characteristics of such actuators are modeled based on equilibrium pressure equation. The model is validated with experimental...... the dominant dynamic characteristics of the core-free tubular actuator. It has been observed that all actuators have similar dynamic characteristics in a frequency range up to 1 kHz. A tubular actuator is then used to provide active vibration isolation (AVI) of a 250 g mass subject to shaker generated 'ground...

  4. Novel tubular and crystalline structures in purified preparations of Newcastle disease virus. Brief report.

    Science.gov (United States)

    Gowans, E J; McNulty, M S

    1979-01-01

    Hitherto undescribed tubular and crystalline structures were detected by negative contrast electron microscopy in purified preparations of Newcastle disease virus. It is suggested that these are viral in origin and are composed of aggregates of viral glycoprotein.

  5. An asymmetric tubular ceramic-carbonate dual phase membrane for high temperature CO2 separation.

    Science.gov (United States)

    Dong, Xueliang; Ortiz Landeros, José; Lin, Y S

    2013-10-25

    For the first time, a tubular asymmetric ceramic-carbonate dual phase membrane was prepared by a centrifugal casting technique and used for high temperature CO2 separation. This membrane shows high CO2 permeation flux and permeance.

  6. VALIDATION OF SIMULATION MODELS FOR DIFFERENTLY DESIGNED HEAT-PIPE EVACUATED TUBULAR COLLECTORS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Dragsted, Janne; Furbo, Simon

    2007-01-01

    Differently designed heat-pipe evacuated tubular collectors have been investigated theoretically and experimentally. The theoretical work has included development of two TRNSYS [1] simulation models for heat-pipe evacuated tubular collectors utilizing solar radiation from all directions. One model...... coating on both sides. The input to the models is thus not a simple collector efficiency expression but the actual collector geometry. In this study, the TRNSYS models are validated with measurements for four differently designed heat-pipe evacuated tubular collectors. The collectors are produced...... cases, a good degree of similarity between measured and calculated results is found. With these validated models detailed parameter analyses and collector design optimization are now possible. Key words: Evacuated tubular collector, Heat pipe, Thermal performance, TRNSYS simulation....

  7. Diaphragmatic suture with tubular stomach to prevent early delayed gastric emptying after esophagectomy

    Institute of Scientific and Technical Information of China (English)

    Chao Sun; Weiping Shi; Yusheng Shu; Hongcan Shi; Shichun Lu; Kang Wang

    2015-01-01

    Objective The objective of this study was to evaluate the clinical ef icacy of a diaphragmatic suture with tubular stomach to prevent delayed gastric emptying (DGE) after esophagectomy through the cervico-tho-racoabdominal approach. Methods A total of 980 patients with esophageal cancer undergoing esophagectomy through the cer-vico-thoracoabdominal approach were retrospectively included in this study and divided into two groups. Al patients underwent tubular stomach creation (group A; n = 530) or a diaphragmatic suture and tubular stomach creation (group B; n = 450). The incidence of early DGE was observed. Results The incidence of early DGE in group A was significantly higher than that in group B (P Conclusion This observation study suggests that the use of a diaphragmatic suture with tubular stomach through the cervico-thoracoabdominal approach can decrease the incidence of early DGE after esopha-gectomy.

  8. EVALUATION OF EVACUATED TUBULAR SOLAR COLLECTORS FOR LARGE SDHW SYSTEMS AND COMBINED SPACE HEATING SYSTEMS

    DEFF Research Database (Denmark)

    Qin, Lin; Furbo, Simon

    1999-01-01

    . Based on thesemodels, the thermal performance of large solar domestic hot water (DHW) systems and combined domestichot water and space heating systems with the four evacuated tubular collectors was determined. To make acomparison with traditional flat-plate collectors, similar simulations were also...... carried out for systems with atypical flat-plate collector. The results show that the thermal advantage of evacuated tubular collectors variesgreatly from system to system, and increases with the solar fraction. Furthermore, the higher the operationtemperature of the collector in the system is......In the present study, detailed investigations on evacuated tubular solar collectors for large solarheating systems have been carried out. Four types of evacuated tubular solar collectors were used in theinvestigation. Based on laboratory tests, simulation models for the collectors were determined...

  9. Interpopulation hybrid breakdown maps to the mitochondrial genome.

    Science.gov (United States)

    Ellison, Christopher K; Burton, Ronald S

    2008-03-01

    Hybrid breakdown, or outbreeding depression, is the loss of fitness observed in crosses between genetically divergent populations. The role of maternally inherited mitochondrial genomes in hybrid breakdown has not been widely examined. Using laboratory crosses of the marine copepod Tigriopus californicus, we report that the low fitness of F(3) hybrids is completely restored in the offspring of maternal backcrosses, where parental mitochondrial and nuclear genomic combinations are reassembled. Paternal backcrosses, which result in mismatched mitochondrial and nuclear genomes, fail to restore hybrid fitness. These results suggest that fitness loss in T. californicus hybrids is completely attributable to nuclear-mitochondrial genomic interactions. Analyses of ATP synthetic capacity in isolated mitochondria from hybrid and backcross animals found that reduced ATP synthesis in hybrids was also largely restored in backcrosses, again with maternal backcrosses outperforming paternal backcrosses. The strong fitness consequences of nuclear-mitochondrial interactions have important, and often overlooked, implications for evolutionary and conservation biology.

  10. Strength of Tubular Joints Made by Electromagnetic Compression at Quasistatic and Cyclic Loading

    OpenAIRE

    Barreiro, P.; Beerwald, C.; Homberg, W.; Kleiner, M.; Löhe, D.; Marré, M.; Schulze, V.

    2006-01-01

    Electromagnetic compression of tubular profiles with high electrical conductivity is an innovative joining process for lightweight structures. The components are joined using pulsed magnetic fields which apply radial pressures of up to 200 MPa to tubular workpieces, causing a symmetric reduction of the diameter with typical strain rates of up to 10^4 sec^(-1). This process avoids any surface damage of the workpiece because there is no contact between component and forming tool. The strength o...

  11. Effect of cisplatin on renal haemodynamics and tubular function in the dog kidney

    DEFF Research Database (Denmark)

    Daugaard, G; Abildgaard, U; Holstein-Rathlou, N H

    1987-01-01

    Administration of cisplatin (5 mg/kg) to dogs results in polyuric renal failure due initially to a proximal tubular functional impairment. 48-72 h after the cisplatin administration the depressed renal function can be attributed to impairment of proximal as well as distal tubular reabsorptive...... capacities associated with increased renal vascular resistance. The polyuria seems to be due to the impaired reabsorption rate in the distal nephron segments....

  12. Distal renal tubular acidosis without renal impairment after use of tenofovir: a case report

    OpenAIRE

    2016-01-01

    Background Tenofovir, one of antiretroviral medication to treat human immunodeficiency virus (HIV) infection, is known to cause proximal renal tubular acidosis such as Fanconi syndrome, but cases of distal renal tubular acidosis had never been reported. Case presentation A 20-year-old man with HIV infection developed nausea and vomiting without diarrhea after starting antiretroviral therapy. Arterial blood gas revealed non-anion-gap metabolic acidosis and urine test showed positive urine anio...

  13. Influence of Geometrical Imperfections on Analyses of Door Openings in Tubular Steel Towers for Wind Turbines.

    OpenAIRE

    Tran, Anh Tuan; Veljkovic, Milan, ed. lit.; Rebelo, Carlos; Da Silva, Luís Simões

    2014-01-01

    Towers for wind turbines are very sensitive to geometrical imperfections. Pattern and amplitude of imperfections significantly influence the strength of the towers. Rather limited number of experiments exists on a tubular tower like structure and no experiments are available considering door opening in towers with cylindrical or polygonal cross-section. One of the objectives of the RFCS research project “HIGH STEEL TUBULAR TOWERS FOR WIND TURBINES, HISTIWIN2” was to investigate current practi...

  14. Fabrication of Coiled Tubular Heat Exchanger%绕管式换热器的制造

    Institute of Scientific and Technical Information of China (English)

    王自涛

    2015-01-01

    本文介绍了绕管换热器的技术特点及应用。从结构设计、技术等方面阐明了绕管换热器的设计制造的问题。%In is paper,the technical characteristics and application of coiled tubular heat exchanger were introduced. And the problem in design and manufacture of coiled tubular heat exchanger were clarified .

  15. Design and performance of tubular flat-plate solid oxide fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Matsushima, T.; Ikeda, D.; Kanagawa, H. [NTT Integrated Information & Energy Systems Labs., Tokyo (Japan)] [and others

    1996-12-31

    With the growing interest in conserving the environmental conditions, much attention is being paid to Solid Oxide Fuel Cell (SOFC), which has high energy-conversion efficiency. Many organizations have conducted studies on tubular and flat type SOFCs. Nippon Telegraph and Telephone Corporation (NTT) has studied a combined tubular flat-plate SOFC, and already presented the I-V characteristics of a single cell. Here, we report the construction of a stack of this SOFC cell and successful generation tests results.

  16. HOPIS: hybrid omnidirectional and perspective imaging system for mobile robots.

    Science.gov (United States)

    Lin, Huei-Yung; Wang, Min-Liang

    2014-09-04

    In this paper, we present a framework for the hybrid omnidirectional and perspective robot vision system. Based on the hybrid imaging geometry, a generalized stereo approach is developed via the construction of virtual cameras. It is then used to rectify the hybrid image pair using the perspective projection model. The proposed method not only simplifies the computation of epipolar geometry for the hybrid imaging system, but also facilitates the stereo matching between the heterogeneous image formation. Experimental results for both the synthetic data and real scene images have demonstrated the feasibility of our approach.

  17. Imaging with Synthetic Aperture Radar

    CERN Document Server

    Massonnet, Didier

    2008-01-01

    Describing a field that has been transformed by the recent availability of data from a new generation of space and airborne systems, the authors offer a synthetic geometrical approach to the description of synthetic aperture radar, one that addresses physicists, radar specialists, as well as experts in image processing.  

  18. Engineering Ecosystems and Synthetic Ecologies#

    OpenAIRE

    Mee, Michael T.; Wang, Harris H.

    2012-01-01

    Microbial ecosystems play an important role in nature. Engineering these systems for industrial, medical, or biotechnological purposes are important pursuits for synthetic biologists and biological engineers moving forward. Here, we provide a review of recent progress in engineering natural and synthetic microbial ecosystems. We highlight important forward engineering design principles, theoretical and quantitative models, new experimental and manipulation tools, and possible applications of ...

  19. Synthetic biology and metabolic engineering.

    Science.gov (United States)

    Stephanopoulos, Gregory

    2012-11-16

    Metabolic engineering emerged 20 years ago as the discipline occupied with the directed modification of metabolic pathways for the microbial synthesis of various products. As such, it deals with the engineering (design, construction, and optimization) of native as well as non-natural routes of product synthesis, aided in this task by the availability of synthetic DNA, the core enabling technology of synthetic biology. The two fields, however, only partially overlap in their interest in pathway engineering. While fabrication of biobricks, synthetic cells, genetic circuits, and nonlinear cell dynamics, along with pathway engineering, have occupied researchers in the field of synthetic biology, the sum total of these areas does not constitute a coherent definition of synthetic biology with a distinct intellectual foundation and well-defined areas of application. This paper reviews the origins of the two fields and advances two distinct paradigms for each of them: that of unit operations for metabolic engineering and electronic circuits for synthetic biology. In this context, metabolic engineering is about engineering cell factories for the biological manufacturing of chemical and pharmaceutical products, whereas the main focus of synthetic biology is fundamental biological research facilitated by the use of synthetic DNA and genetic circuits.

  20. Holographically Correcting Synthetic Aperture Aberrations.

    Science.gov (United States)

    1987-12-01

    Malacara (20:105-148). The synthetic aperture was aligned in accordance with the synthetic-aperture alignment technique of Gill (8:61-64). The...1987. 20. Malacara , Daniel, ed. Optical Shop Testing. New York: John Wiley & Sons, 1978. 21. Marciniak, Capt Michael. Tutorial Presentation of mV

  1. Synthetic peptides for antibody production

    NARCIS (Netherlands)

    Zegers, N.D.

    1995-01-01

    Synthetic peptides are useful tools for the generation of antibodies. The use of antibodies as specific reagents in inununochemical assays is widely applied. In this chapter, the application of synthetic peptides for the generation of antibodies is described. The different steps that lead to the uni

  2. Evaluation of tensile strength of hybrid fiber (jute/gongura) reinforced hybrid polymer matrix composites

    Science.gov (United States)

    Venkatachalam, G.; Gautham Shankar, A.; Vijay, Kumar V.; Chandan, Byral R.; Prabaharan, G. P.; Raghav, Dasarath

    2015-07-01

    The polymer matrix composites attract many industrial applications due to its light weight, less cost and easy for manufacturing. In this paper, an attempt is made to prepare and study of the tensile strength of hybrid (two natural) fibers reinforced hybrid (Natural + Synthetic) polymer matrix composites. The samples were prepared with hybrid reinforcement consists of two different fibers such as jute and Gongura and hybrid polymer consists of polyester and cashew nut shell resins. The hybrid composites tensile strength is evaluated to study the influence of various fiber parameters on mechanical strength. The parameters considered here are the duration of fiber treatment, the concentration of alkali in fiber treatment and nature of fiber content in the composites.

  3. Prevalence of renal tubular dysfunction in beta thalassemia minor in shiraz

    Directory of Open Access Journals (Sweden)

    Ali Moradi Nakhodcheri

    2012-02-01

    Full Text Available  Background & objective: β-Thalassemia minor is an asymptomatic hereditary disease. The first study on the relation of renal tubular dysfunction and β-thalassemia minor was performed in 2002 but those studies seem inadequate.The main goal of this study is through evaluation of renal tubular function in 100 patients with thalassemia minor. Materials & Methods: 100 patients with β- thalassemia which confirmed by hemoglobin electrophoresis and CBC as well as RBC indices were studied.14 out of 100 cases exit because of Urinary Tract Infection, diabetes mellitus or hypertension.Complete chemistry profile was performed on serum and urine of all reminder 86 patients (46 female and 40 male. Patients classified into two groups: β-thalassemia minor with anemia and without anemia. Another control group include 50 healthy individuals also considered.Then data analyzed by proper statistical methods. Results: 20 out of 86 reminder cases e.g. 24% showed at least one index of renal tubular dysfunction.58% of patients was been anemic and 42% non anemic. The most prominent tubular dysfunction was seen in a 29 years old lady with glucosuria and without anemia. conclusion: β-Thalassemia minor is common in Iran specially in Fars province. This study revealed significant renal tubular dysfunction in patient with β-thalassemia minor. So it is necessary to check out thalassemic patients for renal function tests periodically. Key words: β-thalassemia, minor,renal tubular dysfunction

  4. Analysis and Calculation of Axial Stiffness of Tubular X-joints under Compression on Braces

    Institute of Scientific and Technical Information of China (English)

    QIU Guo-zhi; ZHAO Jin-cheng

    2009-01-01

    This paper introduces the influence factors of axial stiffness of tubular X-joints. The analysis model of tubular joints using plate and shell finite element method is also made. Systematic single-parameter analysis of tubular X-joints is performed using Ansys program. The influences of those factors, including ratio of brace diameter to chord diameter (β), ratio of chord diameter to twice chord thickness (γ), ratio of brace wall thickness to that of chord (τ), brace-to-chord intersection angle (θ), and chord stress ratio, ratio of another brace diameter to chord diameter, in-plane and out-of-plane moment of braces, etc., on stiffness of tubular X-joints are analyzed.Two non-dimensional parameters-joint axial stiffness factor ηN and axial force capacity factor ωN are proposed,and the relationship curve of the two factors is determined. Computational formulas of tubular X-joint axial stiffness are obtained by multi-element regression technology. The formulas can be used in design and analysis of steel tubular structures.

  5. Ground Vibration Isolation of Multiple Scattering by Using Rows of Tubular Piles as Barriers

    Directory of Open Access Journals (Sweden)

    Miao-miao Sun

    2014-01-01

    Full Text Available A new formal solution for the multiple scattering of plane harmonic waves by a group of arbitrary configuration tubular piles in an elastic total space is derived. Each order of scattering satisfies prescribed boundary conditions at the interface of tubular piles, which is delivered as the sum of incident and scattering waves. The first order performs the scattering wave by each scattered pile and the subsequent orders resulted from the excitation of each pile of first order of scattering from the remaining tubular piles. Advanced scattering orders can be regarded as the same manners. Several series of scattering coefficients are figured out with the aids of addition theorem so that the exact steady-state solution for the scattered displacement and stress is obtained. Particularly, when internal diameter of tubular piles tends to be infinitely small, it degenerates to a solid pile problem. By imposing the normalized displacement amplitudes and transmissibility indices, the influences of specific parameters such as scattering orders, internal and external diameter ratio of piles, pile material rigidity, position and distances between tubular pile and pile rows, and pile numbers are discussed. Certain recommended conclusions have been drawn as the guidelines of practical engineering design for discontinuous barrier of tubular piles.

  6. Inner Surface Chirality of Single-Handed Twisted Carbonaceous Tubular Nanoribbons.

    Science.gov (United States)

    Liu, Dan; Li, Baozong; Guo, Yongmin; Li, Yi; Yang, Yonggang

    2015-11-01

    Single-handed twisted 4,4'-biphenylene-bridged polybissilsesquioxane tubular nanoribbons and single-layered nanoribbons were prepared by tuning the water/ethanol volume ratio in the reaction mixture at pH = 11.6 through a supramolecular templating approach. The single-layered nanoribbons were formed by shrinking tubular nanoribbons after the removal of the templates. In addition, solvent-induced handedness inversion was achieved. The handedness of the polybissilsesquioxanes could be controlled by changing the ethanol/water volume ratio in the reaction mixture. After carbonization at 900 °C for 4.0 h and removal of silica, single-handed twisted carbonaceous tubular nanoribbons and single-layered nanoribbons with micropores in the walls were obtained. X-ray diffraction and Raman spectroscopy analyses indicated that the carbon is predominantly amorphous. The circular dichroism spectra show that the twisted tubular nanoribbons exhibit optical activity, while the twisted single-layered nanoribbons do not. The results shown here indicate that chirality is transferred from the organic self-assemblies to the inner surfaces of the 4,4'-biphenylene-bridged polybissilsesquioxane tubular nanoribbons and subsequently to those of the carbonaceous tubular nanoribbons.

  7. Human embryonic stem cells differentiate into functional renal proximal tubular-like cells.

    Science.gov (United States)

    Narayanan, Karthikeyan; Schumacher, Karl M; Tasnim, Farah; Kandasamy, Karthikeyan; Schumacher, Annegret; Ni, Ming; Gao, Shujun; Gopalan, Began; Zink, Daniele; Ying, Jackie Y

    2013-04-01

    Renal cells are used in basic research, disease models, tissue engineering, drug screening, and in vitro toxicology. In order to provide a reliable source of human renal cells, we developed a protocol for the differentiation of human embryonic stem cells into renal epithelial cells. The differentiated stem cells expressed markers characteristic of renal proximal tubular cells and their precursors, whereas markers of other renal cell types were not expressed or expressed at low levels. Marker expression patterns of these differentiated stem cells and in vitro cultivated primary human renal proximal tubular cells were comparable. The differentiated stem cells showed morphological and functional characteristics of renal proximal tubular cells, and generated tubular structures in vitro and in vivo. In addition, the differentiated stem cells contributed in organ cultures for the formation of simple epithelia in the kidney cortex. Bioreactor experiments showed that these cells retained their functional characteristics under conditions as applied in bioartificial kidneys. Thus, our results show that human embryonic stem cells can differentiate into renal proximal tubular-like cells. Our approach would provide a source for human renal proximal tubular cells that are not affected by problems associated with immortalized cell lines or primary cells.

  8. mTORC1 maintains renal tubular homeostasis and is essential in response to ischemic stress.

    Science.gov (United States)

    Grahammer, Florian; Haenisch, Nora; Steinhardt, Frederic; Sandner, Lukas; Sander, Lukas; Roerden, Malte; Arnold, Frederic; Cordts, Tomke; Wanner, Nicola; Reichardt, Wilfried; Kerjaschki, Dontscho; Ruegg, Markus A; Hall, Michael N; Moulin, Pierre; Busch, Hauke; Boerries, Melanie; Walz, Gerd; Artunc, Ferruh; Huber, Tobias B

    2014-07-08

    Mammalian target of rapamycin complex 1 (mTORC1) is a key regulator of cell metabolism and autophagy. Despite widespread clinical use of mTORC1 inhibitors, the role of mTORC1 in renal tubular function and kidney homeostasis remains elusive. By using constitutive and inducible deletion of conditional Raptor alleles in renal tubular epithelial cells, we discovered that mTORC1 deficiency caused a marked concentrating defect, loss of tubular cells, and slowly progressive renal fibrosis. Transcriptional profiling revealed that mTORC1 maintains renal tubular homeostasis by controlling mitochondrial metabolism and biogenesis as well as transcellular transport processes involved in countercurrent multiplication and urine concentration. Although mTORC2 partially compensated for the loss of mTORC1, exposure to ischemia and reperfusion injury exaggerated the tubular damage in mTORC1-deficient mice and caused pronounced apoptosis, diminished proliferation rates, and delayed recovery. These findings identify mTORC1 as an important regulator of tubular energy metabolism and as a crucial component of ischemic stress responses.

  9. Tubular proteinuria is the dominant type of proteinuria in an elderly community population in China.

    Science.gov (United States)

    Wang, Hua-Bin; Yang, Qing-Hong; Jiang, Xu; Cui, Xiao-Fan; Liu, Rui

    2015-09-01

    To explore the types of proteinuria in the elderly population in China. Seven hundred and fourteen elderly people (≥ 60 years old) from Tianjin, China, were selected for the study. The albumin-to-creatinine ratio and α1-microglobulin-to-creatinine ratio from morning urine samples were used as indicators of proteinuria. The prevalence of proteinuria was evaluated and the proportion of three different types of proteinuria (mixed, glomerular, and tubular) was assessed in the subjects by analyzing these indicators. Of the 714 subjects, 29.13 % had elevated ACR and 46.36 % had elevated MCR. The proportion of subjects with either elevated ACR or MCR was 53.78 %. The correlation between MCR and ACR was moderate (r = 0.58, R (2) = 0.34, P proteinuria was dominant (45.83 %), followed by mixed glomerular and tubular proteinuria (35.68 %), and significantly higher than glomerular proteinuria. A diet high in salt was the independent risk factor for tubular proteinuria; physical activity was the independent risk factor for glomerular proteinuria. The risk of glomerular proteinuria was lower in males than in females, but the risk of tubular proteinuria was higher in males. The prevalence of tubular proteinuria was higher than that of glomerular proteinuria, and the risk factors are different, in the elderly in China; therefore, tubular damage markers should get more attention in the overall population.

  10. Semiconductor quantum dot-inorganic nanotube hybrids.

    Science.gov (United States)

    Kreizman, Ronen; Schwartz, Osip; Deutsch, Zvicka; Itzhakov, Stella; Zak, Alla; Cohen, Sidney R; Tenne, Reshef; Oron, Dan

    2012-03-28

    A synthetic route for preparation of inorganic WS(2) nanotube (INT)-colloidal semiconductor quantum dot (QD) hybrid structures is developed, and transient carrier dynamics on these hybrids are studied via transient photoluminescence spectroscopy utilizing several different types of QDs. Measurements reveal efficient resonant energy transfer from the QDs to the INT upon photoexcitation, provided that the QD emission is at a higher energy than the INT direct gap. Charge transfer in the hybrid system, characterized using QDs with band gaps below the INT direct gap, is found to be absent. This is attributed to the presence of an organic barrier layer due to the relatively long-chain organic ligands of the QDs under study. This system, analogous to carbon nanotube-QD hybrids, holds potential for a variety of applications, including photovoltaics, luminescence tagging and optoelectronics.

  11. Prospects for Hybrid Breeding in Bioenergy Grasses

    DEFF Research Database (Denmark)

    Aguirre, Andrea Arias; Studer, Bruno; Frei, Ursula

    2012-01-01

    of different hybrid breeding schemes to optimally exploit heterosis for biomass yield in perennial ryegrass (Lolium perenne L.) and switchgrass (Panicum virgatum), two perennial model grass species for bioenergy production. Starting with a careful evaluation of current population and synthetic breeding methods......, we address crucial topics to implement hybrid breeding, such as the availability and development of heterotic groups, as well as biological mechanisms for hybridization control such as self-incompatibility (SI) and male sterility (MS). Finally, we present potential hybrid breeding schemes based on SI...... and MS for the two bioenergy grass species, and discuss how molecular tools and synteny can be used to transfer relevant information for genes controlling these biological mechanisms across grass species...

  12. Ecotoxicology of synthetic pyrethroids.

    Science.gov (United States)

    Maund, S J; Campbell, P J; Giddings, J M; Hamer, M J; Henry, K; Pilling, E D; Warinton, J S; Wheeler, J R

    2012-01-01

    In this chapter we review the ecotoxicology of the synthetic pyrethroids (SPs). SPs are potent, broad-spectrum insecticides. Their effects on a wide range of nontarget species have been broadly studied, and there is an extensive database available to evaluate their effects. SPs are highly toxic to fish and aquatic invertebrates in the laboratory, but effects in the field are mitigated by rapid dissipation and degradation. Due to their highly lipophilic nature, SPs partition extensively into sediments. Recent studies have shown that toxicity in sediment can be predicted on the basis of equilibrium partitioning, and whilst other factors can influence this, organic carbon content is a key determining variable. At present for SPs, there is no clear evidence for adverse population-relevant effects with an underlying endocrine mode of action. SPs have been studied intensively in aquatic field studies, and their effects under field conditions are mitigated from those measured in the laboratory by their rapid dissipation and degradation. Studies with a range of test systems have shown consistent aquatic field endpoints across a variety of geographies and trophic states. SPs are also highly toxic to bees and other nontarget arthropods in the laboratory. These effects are mitigated in the field through repellency and dissipation of residues, and recovery from any adverse effects tends to be rapid.

  13. Synthetic biology: lessons from the history of synthetic organic chemistry.

    Science.gov (United States)

    Yeh, Brian J; Lim, Wendell A

    2007-09-01

    The mid-nineteenth century saw the development of a radical new direction in chemistry: instead of simply analyzing existing molecules, chemists began to synthesize them--including molecules that did not exist in nature. The combination of this new synthetic approach with more traditional analytical approaches revolutionized chemistry, leading to a deep understanding of the fundamental principles of chemical structure and reactivity and to the emergence of the modern pharmaceutical and chemical industries. The history of synthetic chemistry offers a possible roadmap for the development and impact of synthetic biology, a nascent field in which the goal is to build novel biological systems.

  14. Perfluorooctanesulfonate Mediates Renal Tubular Cell Apoptosis through PPARgamma Inactivation.

    Directory of Open Access Journals (Sweden)

    Li-Li Wen

    Full Text Available Perfluorinated chemicals (PFCs are ubiquitously distributed in the environments including stainless pan-coating, raincoat, fire extinguisher, and semiconductor products. The PPAR family has been shown to contribute to the toxic effects of PFCs in thymus, immune and excretory systems. Herein, we demonstrated that perfluorooctanesulfonate (PFOS caused cell apoptosis through increasing ratio of Bcl-xS/xL, cytosolic cytochrome C, and caspase 3 activation in renal tubular cells (RTCs. In addition, PFOS increased transcription of inflammatory cytokines (i.e., TNFα, ICAM1, and MCP1 by NFκB activation. Conversely, PFOS reduced the mRNA levels of antioxidative enzymes, such as glutathione peroxidase, catalase, and superoxide dismutase, as a result of reduced PPARγ transactivational activity by using reporter and chromatin immuoprecipitation (ChIP assays. PFOS reduced the protein interaction between PPARγ and PPARγ coactivator-1 alpha (PGC1α by PPARγ deacetylation through Sirt1 upregulation, of which the binding of PPARγ and PGC1α to a peroxisome proliferator response element (PPRE in the promoter regions of these antioxidative enzymes was alleviated in the ChIP assay. Furthermore, Sirt1 also deacetylated p53 and then increased the binding of p53 to Bax, resulting in increased cytosolic cytochrome C. The effect of PPARγ inactivation by PFOS was validated using the PPARγ antagonist GW9662, whereas the adverse effects of PFOS were prevented by PPARγ overexpression and activators, rosiglitozone and L-carnitine, in RTCs. The in vitro finding of protective effect of L-carnitine was substantiated in vivo using Balb/c mice model subjected to PFOS challenge. Altogether, we provide in vivo and in vitro evidence for the protective mechanism of L-carnitine in eliminating PFOS-mediated renal injury, at least partially, through PPARγ activation.

  15. [Itai-itai disease: cadmium-induced renal tubular osteomalacia].

    Science.gov (United States)

    Aoshima, Keiko

    2012-01-01

    Cadmium (Cd) is one of the most toxic elements to which humans could be exposed at work or in the environment. The outbreak of itai-itai disease, which is the most severe stage of chronic Cd poisoning, occurred in the Cd-polluted Jinzu River basin in Toyama. In this area, the river was contaminated by slag from a mine upstream; as a consequence, the soil in rice paddies was polluted with heavy metals including Cd through irrigation water from around 1910 to the 1960s. The government of Toyama prefecture carried out an extensive survey on Cd concentration in rice and soil of the paddy fields and declared that the upper layer of a total of 1500 ha of paddy fields should be replaced by nonpolluted soil. Then, an intervention program of soil replacement in the polluted paddy fields was continually carried out from 1980 to 2011. As a result, Cd concentration in rice markedly decreased. The kidney is the organ critically affected after long-term exposure to Cd. Proximal tubular dysfunction (RTD) has been found among the inhabitants of the Jinzu River basin. The very recent report by the Environmental Agency in Japan in 2009 has disclosed that b2-microglobulinuria with RTD is still found at a high prevalence among the inhabitants of the Jinzu River basin of both sexes. Twenty patients with itai-itai disease (1 male and 19 females), who attended our hospital and received medical examination during 2000 to 2008, had applied for recognition as itai-itai disease patients to the government of Toyama prefecture. In this paper, the recent epidemiological and clinical features of itai-itai disease are discussed on the basis of a review of the cases of these 19 female patients.

  16. Effect of Air Flow on Tubular Solar Still Efficiency

    Directory of Open Access Journals (Sweden)

    Arunkumar Thirugnanasambantham

    2013-04-01

    Full Text Available An experimental work was reported to estimate the increase in distillate yield for a compound parabolic concentrator-concentric tubular solar still (CPC-CTSS. The CPC dramatically increases the heating of the saline water. A novel idea was proposed to study the characteristic features of CPC for desalination to produce a large quantity of distillate yield. A rectangular basin of dimension 2 m × 0.025 m × 0.02 m was fabricated of copper and was placed at the focus of the CPC. This basin is covered by two cylindrical glass tubes of length 2 m with two different diameters of 0.02 m and 0.03 m. The experimental study was operated with two modes: without and with air flow between inner and outer tubes. The rate of air flow was fixed throughout the experiment at 4.5 m/s. On the basis of performance results, the water collection rate was 1445 ml/day without air flow and 2020 ml/day with air flow and the efficiencies were 16.2% and 18.9%, respectively.Findings:The experimental study was operated with two modes: without and with air flow between inner and outer tubes. The rate of air flow was fixed throughout the experiment at 4.5 m/s.Conclusions:On the basis of performance results, the water collection rate was 1445 ml/day without air flow and 2020 ml/day with air flow and the efficiencies were 16.2% and 18.9%, respectively.

  17. Design, construction and evaluation of solarized airlift tubular photobioreactor

    Science.gov (United States)

    Bahadur, A.; Zubair, M.; Khan, M. B.

    2013-06-01

    An innovative photobioreactor is developed for growing algae in simulated conditions. The proposed design comprises of a continuous tubular irradiance loop and air induced liquid circulation with gas separation through air lift device. The unique features of air lift system are to ensure the shear free circulation of sensitive algal culture and induce light/dark cycles to the photosynthetic micro-organisms. The design strategy employs to model and construct a 20-liter laboratory scale unit using Boro-silicate glass tubing. The material is selected to ensure maximum photon transmission. All components of the device are designed to have flexibility to be replaced with an alternative design, providing fair chance of modification for future investigators. The principles of fluid mechanics are applied to describe geometrical attributes of the air lift system. Combination of LEDs and Florescent tube lights (Warm white) were used to illuminate the photosynthesis reaction area providing a possibility to control both illumination duration and light intensity. 200 Watt Solar PV system is designed to power up the device which included air pump (100 Watt) and illumination system (100 Watt). Algal strain Chlorella sp was inoculated in photobioreactor which was sparged with air and carbon dioxide. The growth was sustained in the batch mode with daily monitoring of temperature, pH and biomass concentration. The novel photobioreactor recorded a maximum experimental average yield of 0.65 g/l.day (11.3 g/m2.day) as compared to theoretical modeled yield of 0.82 g/l.day (14.26 g/m2.day), suggesting the device can be efficiently and cost-effectively employed in the production of algal biomass for biofuels, concomitantly mitigating CO2.

  18. Spicing thing up: Synthetic cannabinoids

    Science.gov (United States)

    Spaderna, Max; Addy, Peter H; D’Souza, Deepak Cyril

    2013-01-01

    Rationale Recently, products containing synthetic cannabinoids, collectively referred to as Spice, are increasingly being used recreationally. Objectives The availability, acute subjective effects—including self-reports posted on Erowid—laboratory detection, addictive potential, and regulatory challenges of the Spice phenomenon are reviewed. Results Spice is sold under the guise of potpourri or incense. Unlike THC, the synthetic cannabinoids present in Spice are high-potency, high-efficacy, cannabinoid-receptor full agonists. Since standard urine toxicology does not test for the synthetic cannabinoids in Spice, it is often used by those who want to avoid detection of drug use. These compounds have not yet been subjected to rigorous testing in humans. Acute psychoactive effects include changes in mood, anxiety, perception, thinking, memory, and attention. Adverse effects include anxiety, agitation, panic, dysphoria, psychosis, and bizarre behavior. Psychosis outcomes associated with Spice provide additional data linking cannabinoids and psychosis. Adverse events necessitating intervention by Poison Control Centers, law enforcement, emergency responders, and hospitals are increasing. Despite statutes prohibiting the manufacture, distribution, and sale of Spice products, manufacturers are replacing banned compounds with newer synthetic cannabinoids that are not banned. Conclusions There is an urgent need for better research on the effects of synthetic cannabinoids to help clinicians manage adverse events and to better understand cannabinoid pharmacology in humans. The reported psychosis outcomes associated with synthetic cannabinoids contribute to the ongoing debate on the association between cannabinoids and psychosis. Finally, drug-detection tests for synthetic cannabinoids need to become clinically available. PMID:23836028

  19. Synthetic biology and personalized medicine.

    Science.gov (United States)

    Jain, K K

    2013-01-01

    Synthetic biology, application of synthetic chemistry to biology, is a broad term that covers the engineering of biological systems with structures and functions not found in nature to process information, manipulate chemicals, produce energy, maintain cell environment and enhance human health. Synthetic biology devices contribute not only to improve our understanding of disease mechanisms, but also provide novel diagnostic tools. Methods based on synthetic biology enable the design of novel strategies for the treatment of cancer, immune diseases metabolic disorders and infectious diseases as well as the production of cheap drugs. The potential of synthetic genome, using an expanded genetic code that is designed for specific drug synthesis as well as delivery and activation of the drug in vivo by a pathological signal, was already pointed out during a lecture delivered at Kuwait University in 2005. Of two approaches to synthetic biology, top-down and bottom-up, the latter is more relevant to the development of personalized medicines as it provides more flexibility in constructing a partially synthetic cell from basic building blocks for a desired task. Copyright © 2012 S. Karger AG, Basel.

  20. Urinary excretion of beta 2-glycoprotein-1 (apolipoprotein H) and other markers of tubular malfunction in "non-tubular" renal disease.

    Science.gov (United States)

    Flynn, F. V.; Lapsley, M.; Sansom, P. A.; Cohen, S. L.

    1992-01-01

    AIM: To determine whether urinary beta 2-glycoprotein-1 assays can provide improved discrimination between chronic renal diseases which are primarily of tubular or glomerular origin. METHODS: Urinary beta 2-glycoprotein-1, retinol-binding protein, alpha 1-microglobulin, beta 2-microglobulin, N-acetyl-beta-D-glucosa-minidase and albumin were measured in 51 patients with primary glomerular disease, 23 with obstructive nephropathy, and 15 with polycystic kidney disease, and expressed per mmol of creatinine. Plasma beta 2-glycoprotein-1 was assayed in 52 patients and plasma creatinine in all 89. The findings were compared between the diagnostic groups and with previously published data relating to primary tubular disorders. RESULTS: All 31 patients with plasma creatinine greater than 200 mumol/l excreted increased amounts of beta 2-glycoprotein-1, retinol-binding protein, and alpha 1-microglobulin, and 29 had increased N-acetyl-beta-D-glucosaminidase; the quantities were generally similar to those found in comparable patients with primary tubular pathology. Among 58 with plasma creatinine concentrations under 200 mumol/l, increases in beta 2-glycoprotein-1, retinol-binding protein, and alpha 1-microglobulin excretion were less common and much smaller, especially in those with obstructive nephropathy and polycystic disease. The ratios of the excretion of albumin to the other proteins provided the clearest discrimination between the patients with glomerular or tubular malfunction, but an area of overlap was present which embraced those with obstructive nephropathy and polycystic disease. CONCLUSIONS: Increased excretion of beta 2-glycoprotein-1 due to a raised plasma concentration or diminution of tubular reabsorption, or both, is common in all the forms of renal disease investigated, and both plasma creatinine and urinary albumin must be taken into account when interpreting results. Ratios of urinary albumin: beta 2-glycoprotein-1 greater than 1000 are highly suggestive

  1. Synthetic biology: advancing biological frontiers by building synthetic systems

    Science.gov (United States)

    2012-01-01

    Advances in synthetic biology are contributing to diverse research areas, from basic biology to biomanufacturing and disease therapy. We discuss the theoretical foundation, applications, and potential of this emerging field. PMID:22348749

  2. Synthetic biology: advancing biological frontiers by building synthetic systems

    OpenAIRE

    Chen, Yvonne Yu-Hsuan; Galloway, Kate E; Smolke, Christina D.

    2012-01-01

    Advances in synthetic biology are contributing to diverse research areas, from basic biology to biomanufacturing and disease therapy. We discuss the theoretical foundation, applications, and potential of this emerging field.

  3. Dicarboxylic esters: Useful tools for the biocatalyzed synthesis of hybrid compounds and polymers

    OpenAIRE

    Ivan Bassanini; Karl Hult; Sergio Riva

    2015-01-01

    Dicarboxylic acids and their derivatives (esters and anhydrides) have been used as acylating agents in lipase-catalyzed reactions in organic solvents. The synthetic outcomes have been dimeric or hybrid derivatives of bioactive natural compounds as well as functionalized polyesters.

  4. The Ethics of Synthetic Biology

    DEFF Research Database (Denmark)

    Christiansen, Andreas

    The dissertation analyses and discusses a number of ethical issues that have been raised in connection with the development of synthetic biology. Synthetic biology is a set of new techniques for DNA-level design and construction of living beings with useful properties. The dissertation especially......) popular responsesto them succeed, and whether the objections are ultimately persuasive.2. Given that synthetic biology is a new technology, there is a certain degree of uncertainty about its ultimate effects, and many perceive the technology as risky. I discuss two common approaches in risk regulation...

  5. Synthetic biology for therapeutic applications.

    Science.gov (United States)

    Abil, Zhanar; Xiong, Xiong; Zhao, Huimin

    2015-02-02

    Synthetic biology is a relatively new field with the key aim of designing and constructing biological systems with novel functionalities. Today, synthetic biology devices are making their first steps in contributing new solutions to a number of biomedical challenges, such as emerging bacterial antibiotic resistance and cancer therapy. This review discusses some synthetic biology approaches and applications that were recently used in disease mechanism investigation and disease modeling, drug discovery and production, as well as vaccine development and treatment of infectious diseases, cancer, and metabolic disorders.

  6. The Ethics of Synthetic Biology

    DEFF Research Database (Denmark)

    Christiansen, Andreas

    The dissertation analyses and discusses a number of ethical issues that have been raised in connection with the development of synthetic biology. Synthetic biology is a set of new techniques for DNA-level design and construction of living beings with useful properties. The dissertation especially......) popular responsesto them succeed, and whether the objections are ultimately persuasive.2. Given that synthetic biology is a new technology, there is a certain degree of uncertainty about its ultimate effects, and many perceive the technology as risky. I discuss two common approaches in risk regulation...

  7. Experimental and numerical investigation of expandable tubular structural integrity for well applications

    Directory of Open Access Journals (Sweden)

    T. Pervez

    2010-07-01

    Full Text Available Purpose: The ever-increasing energy demand has forced researchers to search for new and cheaper solutions for oil and gas production. The recent development of solid expandable tubulars (SETs has resulted in design of slim oil and gas wells. The large plastic deformation experienced by the tubular under down-hole environment may result in premature and unexpected failures. The objective of this research is to investigate the structural integrity of SET for well applications to avoid such failures.Design/methodology/approach: In order to achieve the objectives, simulation work was carried out using finite element method and experimental tests were conducted on full size tubular for validation of numerical results.Findings: The required drawing force for expansion under different expansion ratios, surplus deformation, variations in tubular thickness and length were estimated numerically and experimentally. The differences in values using two approaches vary from 5% to 12%. Tubular wall thickness decreases as the mandrel angle, expansion ratio, and friction coefficient increase.Research limitations/implications: The issue of maximum expansion a tubular can be subjected to needs to be further investigated. Furthermore, the pre and post-expansion material properties need immediate attention of researchers to fulfil the dream of low-cost expandable solution.Practical implications: In recent years, solid expandable tubular technology has already made significant inroads in replacing conventional telescopic oil wells. It allows design and realization of slim wells, accessing difficult and ultra-deep reservoirs, well remediation, zonal isolation, drilling of directional and horizontal wells, etc.Originality/value: SET is an emerging technology for oil and gas industry. The current findings are very valuable for researchers and well engineers to design slim wells and enhance the productivity of older wells.

  8. Shear Stress-Induced Alteration of Epithelial Organization in Human Renal Tubular Cells.

    Directory of Open Access Journals (Sweden)

    Damien Maggiorani

    Full Text Available Tubular epithelial cells in the kidney are continuously exposed to urinary fluid shear stress (FSS generated by urine movement and recent in vitro studies suggest that changes of FSS could contribute to kidney injury. However it is unclear whether FSS alters the epithelial characteristics of the renal tubule. Here, we evaluated in vitro and in vivo the influence of FSS on epithelial characteristics of renal proximal tubular cells taking the organization of junctional complexes and the presence of the primary cilium as markers of epithelial phenotype. Human tubular cells (HK-2 were subjected to FSS (0.5 Pa for 48 h. Control cells were maintained under static conditions. Markers of tight junctions (Claudin-2, ZO-1, Par polarity complex (Pard6, adherens junctions (E-Cadherin, β-Catenin and the primary cilium (α-acetylated Tubulin were analysed by quantitative PCR, Western blot or immunocytochemistry. In response to FSS, Claudin-2 disappeared and ZO-1 displayed punctuated and discontinuous staining in the plasma membrane. Expression of Pard6 was also decreased. Moreover, E-Cadherin abundance was decreased, while its major repressors Snail1 and Snail2 were overexpressed, and β-Catenin staining was disrupted along the cell periphery. Finally, FSS subjected-cells exhibited disappeared primary cilium. Results were confirmed in vivo in a uninephrectomy (8 months mouse model where increased FSS induced by adaptive hyperfiltration in remnant kidney was accompanied by both decreased epithelial gene expression including ZO-1, E-cadherin and β-Catenin and disappearance of tubular cilia. In conclusion, these results show that proximal tubular cells lose an important number of their epithelial characteristics after long term exposure to FSS both in vitro and in vivo. Thus, the changes in urinary FSS associated with nephropathies should be considered as potential insults for tubular cells leading to disorganization of the tubular epithelium.

  9. Hybrid microelectronic technology

    Science.gov (United States)

    Moran, P.

    Various areas of hybrid microelectronic technology are discussed. The topics addressed include: basic thick film processing, thick film pastes and substrates, add-on components and attachment methods, thin film processing, and design of thick film hybrid circuits. Also considered are: packaging hybrid circuits, automating the production of hybrid circuits, application of hybrid techniques, customer's view of hybrid technology, and quality control and assurance in hybrid circuit production.

  10. ASSESMENT OF SELF HEALING PROPERTY IN HYBRID FIBER POLYMERIC COMPOSITE

    OpenAIRE

    2011-01-01

    In recent years, Natural fiber reinforced composites is an emerging area in polymer technology. Fibers resulting from plants are considered a budding substitute for non-renewable synthetic fibers like glass and carbon fibers. The objective of this study is to merge the benefits of natural and synthetic fibers by developing ahybrid composite of jute and glass fibers along with self healing property to eliminate delamination without compromising the benefits of hybridization. This concept offer...

  11. Hybrid microspheres

    Science.gov (United States)

    Rembaum, Alan (Inventor); Yen, Richard C. K. (Inventor)

    1985-01-01

    Substrates, particularly inert synthetic organic resin beads (10) or sheet (12) such as polystyrene are coated with a covalently bound layer (24) of polyacrolein by irradiation a solution (14) of acrolein or other aldehyde with high intensity radiation. Individual microspheres (22) are formed which attach to the surface to form the aldehyde containing layer (24). The aldehyde groups can be converted to other functional groups by reaction with materials such as hydroxylamine. Adducts of proteins such as antibodies or enzymes can be formed by direct reaction with the surface aldehyde groups.

  12. Synthetic biology: ethical ramifications 2009.

    Science.gov (United States)

    Rabinow, Paul; Bennett, Gaymon

    2009-12-01

    During 2007 and 2008 synthetic biology moved from the manifesto stage to research programs. As of 2009, synthetic biology is ramifying; to ramify means to produce differentiated trajectories from previous determinations. From its inception, most of the players in synthetic biology agreed on the need for (a) rationalized design and construction of new biological parts, devices, and systems as well as (b) the re-design of natural biological systems for specified purposes, and that (c) the versatility of designed biological systems makes them suitable to address such challenges as renewable energy, the production of inexpensive drugs, and environmental remediation, as well as providing a catalyst for further growth of biotechnology. What is understood by these goals, however, is diverse. Those assorted understandings are currently contributing to different ramifications of synthetic biology. The Berkeley Human Practices Lab, led by Paul Rabinow, is currently devoting its efforts to documenting and analyzing these ramifications as they emerge.

  13. Programming languages for synthetic biology.

    Science.gov (United States)

    Umesh, P; Naveen, F; Rao, Chanchala Uma Maheswara; Nair, Achuthsankar S

    2010-12-01

    In the backdrop of accelerated efforts for creating synthetic organisms, the nature and scope of an ideal programming language for scripting synthetic organism in-silico has been receiving increasing attention. A few programming languages for synthetic biology capable of defining, constructing, networking, editing and delivering genome scale models of cellular processes have been recently attempted. All these represent important points in a spectrum of possibilities. This paper introduces Kera, a state of the art programming language for synthetic biology which is arguably ahead of similar languages or tools such as GEC, Antimony and GenoCAD. Kera is a full-fledged object oriented programming language which is tempered by biopart rule library named Samhita which captures the knowledge regarding the interaction of genome components and catalytic molecules. Prominent feature of the language are demonstrated through a toy example and the road map for the future development of Kera is also presented.

  14. Is synthetic biology mechanical biology?

    Science.gov (United States)

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  15. Synthetic Biology for Specialty Chemicals.

    Science.gov (United States)

    Markham, Kelly A; Alper, Hal S

    2015-01-01

    In this review, we address recent advances in the field of synthetic biology and describe how those tools have been applied to produce a wide variety of chemicals in microorganisms. Here we classify the expansion of the synthetic biology toolbox into three different categories based on their primary function in strain engineering-for design, for construction, and for optimization. Next, focusing on recent years, we look at how chemicals have been produced using these new synthetic biology tools. Advances in producing fuels are briefly described, followed by a more thorough treatment of commodity chemicals, specialty chemicals, pharmaceuticals, and nutraceuticals. Throughout this review, an emphasis is placed on how synthetic biology tools are applied to strain engineering. Finally, we discuss organism and host strain diversity and provide a future outlook in the field.

  16. SYNTHETIC SLING FAILURE - EVALUATIONS & RECOMMENDATIONS

    Energy Technology Data Exchange (ETDEWEB)

    MACKEY TC; HENDERSON CS

    2009-10-26

    The information and evaluations provided in this report were compiled to address the recurring problem of synthetic sling failure. As safety is the number one priority in all work aspects, a solution must be devised to prevent accidents from occurring. A total of thirteen cases regarding synthetic sling failure were evaluated in order to determine their causes, effects, and preventative measures. From the collected data, it was found that all cases in which the synthetic sling contacted the edge of its load resulted in sling failure. It is required that adequate synthetic sling protection devices be used to protect slings in any lift where the sling comes in direct contact with the edge or corner of its load. However, there are no consensus codes or standards stating the type, material, or purpose of the type of protective device used to protect the sling from being cut. Numerous industry standards and codes provide vague descriptions on how to protect synthetic slings. Without a clear, concise statement of how to protect synthetic slings, it is common for inadequate materials and sling protection devices to be used in an attempt to meet the intent of these requirements. The use of an inadequate sling protection device is the main cause of synthetic sling failure in all researched cases. Commercial sling protection devices come in many shapes and sizes, and have a variety of names, as well as advertised uses. 'Abrasion pads' and 'wear protectors' are two different names for products with the same intended purpose. There is no distinguishable way to determine the extent of sling protection which these devices will provide, or what specific scenarios they are made for. This creates room for error in a field where error is unacceptable. This report provides a recommended action for hoisting and rigging activities which require synthetic slings to contact a load, as well as recommended changes to industry standards which will benefit overall

  17. Osteomalacia complicating renal tubular acidosis in association with Sjogren's syndrome.

    Science.gov (United States)

    El Ati, Zohra; Fatma, Lilia Ben; Boulahya, Ghada; Rais, Lamia; Krid, Madiha; Smaoui, Wided; Maiz, Hedi Ben; Beji, Soumaya; Zouaghi, Karim; Moussa, Fatma Ben

    2014-09-01

    Renal involvement in Sjogren's syndrome (SS) is not uncommon and may precede other complaints. Tubulointerstitial nephritis is the most common renal disease in SS and may lead to renal tubular acidosis (RTA), which in turn may cause osteomalacia. Nevertheless, osteomalacia rarely occurs as the first manifestation of a renal tubule disorder due to SS. We herewith describe a 43-year-old woman who was admitted to our hospital for weakness, lumbago and inability to walk. X-ray of the long bones showed extensive demineralization of the bones. Laboratory investigations revealed chronic kidney disease with serum creatinine of 2.3 mg/dL and creatinine clearance of 40 mL/min, hypokalemia (3.2 mmol/L), hypophosphatemia (0.4 mmol/L), hypocalcemia (2.14 mmol/L) and hyperchloremic metabolic acidosis (chlorine: 114 mmol/L; alkaline reserve: 14 mmol/L). The serum alkaline phosphatase levels were elevated. The serum levels of 25-hydroxyvitamin D and 1,25-dihydroxy vitamin D were low and borderline low, respectively, and the parathyroid hormone level was 70 pg/L. Urinalysis showed inappropriate alkaline urine (urinary PH: 7), glycosuria with normal blood glucose, phosphaturia and uricosuria. These values indicated the presence of both distal and proximal RTA. Our patient reported dryness of the mouth and eyes and Schirmer's test showed xerophthalmia. An accessory salivary gland biopsy showed changes corresponding to stage IV of Chisholm and Masson score. Kidney biopsy showed diffuse and severe tubulo-interstitial nephritis with dense lymphoplasmocyte infiltrates. Sicca syndrome and renal interstitial infiltrates indicated SS as the underlying cause of the RTA and osteomalacia. The patient received alkalinization, vitamin D (Sterogyl ®), calcium supplements and steroids in an initial dose of 1 mg/kg/day, tapered to 10 mg daily. The prognosis was favorable and the serum creatinine level was 1.7 mg/dL, calcium was 2.2 mmol/L and serum phosphate was 0.9 mmol/L.

  18. Medullary nephrocalcinosis, distal renal tubular acidosis and polycythaemia in a patient with nephrotic syndrome

    Directory of Open Access Journals (Sweden)

    Karunarathne Suneth

    2012-07-01

    Full Text Available Abstract Background Medullary nephrocalcinosis and distal renal tubular acidosis are closely associated and each can lead to the other. These clinical entities are rare in patients with nephrotic syndrome and polycythaemia is an unusual finding in such patients. We describe the presence of medullary nephrocalcinosis, distal renal tubular acidosis and polycythaemia in a patient with nephrotic syndrome due to minimal change disease. Proposed mechanisms of polycythaemia in patients with nephrotic syndrome and distal renal tubular acidosis include, increased erythropoietin production and secretion of interleukin 8 which in turn stimulate erythropoiesis. Case presentation A 22 year old Sri Lankan Sinhala male with nephrotic syndrome due to minimal change disease was investigated for incidentally detected polycythaemia. Investigations revealed the presence of renal tubular acidosis type I and medullary nephrocalcinosis. Despite extensive investigation, a definite cause for polycythaemia was not found in this patient. Treatment with potassium and bicarbonate supplementation with potassium citrate led to correction of acidosis thereby avoiding the progression of nephrocalcinosis and harmful effects of chronic acidosis. Conclusion The constellation of clinical and biochemical findings in this patient is unique but the pathogenesis of erythrocytosis is not clearly explained. The proposed mechanisms for erythrocytosis in other patients with proteinuria include increased erythropoietin secretion due to renal hypoxia and increased secretion of interleukin 8 from the kidney. This case illustrates that there may exist hitherto unknown connections between tubular and glomerular dysfunction in patients with nephrotic syndrome.

  19. Molecular Markers of Tubulointerstitial Fibrosis and Tubular Cell Damage in Patients with Chronic Kidney Disease.

    Directory of Open Access Journals (Sweden)

    Shunsaku Nakagawa

    Full Text Available In chronic kidney disease (CKD, progressive nephron loss causes glomerular sclerosis, as well as tubulointerstitial fibrosis and progressive tubular injury. In this study, we aimed to identify molecular changes that reflected the histopathological progression of renal tubulointerstitial fibrosis and tubular cell damage. A discovery set of renal biopsies were obtained from 48 patients with histopathologically confirmed CKD, and gene expression profiles were determined by microarray analysis. The results indicated that hepatitis A virus cellular receptor 1 (also known as Kidney Injury Molecule-1, KIM-1, lipocalin 2 (also known as neutrophil gelatinase-associated lipocalin, NGAL, SRY-box 9, WAP four-disulfide core domain 2, and NK6 homeobox 2 were differentially expressed in CKD. Their expression levels correlated with the extent of tubulointerstitial fibrosis and tubular cell injury, determined by histopathological examination. The expression of these 5 genes was also increased as kidney damage progressed in a rodent unilateral ureteral obstruction model of CKD. We calculated a molecular score using the microarray gene expression profiles of the biopsy specimens. The composite area under the receiver operating characteristics curve plotted using this molecular score showed a high accuracy for diagnosing tubulointerstitial fibrosis and tubular cell damage. The robust sensitivity of this score was confirmed in a validation set of 5 individuals with CKD. These findings identified novel molecular markers with the potential to contribute to the detection of tubular cell damage and tubulointerstitial fibrosis in the kidney.

  20. Losartan attenuates renal interstitial fibrosis and tubular cell apoptosis in a rat model of obstructive nephropathy.

    Science.gov (United States)

    He, Ping; Li, Detian; Zhang, Beiru

    2014-08-01

    Ureteral obstruction leads to renal injury and progresses to irreversible renal fibrosis, with tubular cell atrophy and apoptosis. There is conflicting evidence concerning whether losartan (an angiotensin II type I receptor antagonist) mitigates renal interstitial fibrosis and renal tubular epithelial cell apoptosis following unilateral ureteral obstruction (UUO) in animal models. The aim of this study was to investigate the effect and mechanism of losartan on renal tubular cell apoptosis and renal fibrosis in a rat model of UUO. The rats were subjected to UUO by ureteral ligation and were treated with dimethyl sulfoxide (control) or losartan. The controls underwent sham surgery. The renal tissues were collected 3, 5, 7 and 14 days after surgery for measurement of various indicators of renal fibrosis. UUO increased the expression levels of α‑smooth muscle actin and collagen I, and the extent of renal tubular fibrosis and apoptosis in a time‑dependent manner. Losartan treatment partially attenuated these responses. Progression of renal interstitial fibrosis was accompanied by phosphorylation of signal transducer and activator of transcription 3 (STAT3) and altered the expression levels of two apoptosis‑related proteins (Bax and Bcl2). Losartan treatment also partially attenuated these responses. The results indicated that losartan attenuated renal fibrosis and renal tubular cell apoptosis in a rat model of UUO. This effect appeared to be mediated by partial blockage of STAT3 phosphorylation.

  1. Tubular Tissues and Organs of Human Body--Challenges in Regenerative Medicine.

    Science.gov (United States)

    Góra, Aleksander; Pliszka, Damian; Mukherjee, Shayanti; Ramakrishna, Seeram

    2016-01-01

    Tissue engineering of tubular organs such as the blood vessel, trachea gastrointestinal tract, urinary tract are of the great interest due to the high amount of surgeries performed annually on those organs. Development in tissue engineering in recent years and promising results, showed need to investigate more complex constructs that need to be designed in special manner. Stent technology remain the most widely used procedure to restore functions of tubular tissues after cancer treatment, or after organ removal due to traumatic accidents. Tubular structures like blood vessels, intestines, and trachea have to work in specific environment at the boundary of the liquids, solids or air and surrounding tissues and ensure suitable separation between them. This brings additional challenges in tissue engineering science in order to construct complete organs by using combinations of various cells along with the support material systems. Here we give a comprehensive review of the tubular structures of the human body, in perspective of the current methods of treatment and progress in regenerative medicine that aims to develop fully functioning organs of tubular shape. Extensive analysis of the available literature has been done focusing on materials and methods of creations of such organs. This work describes the attempts to incorporate growth factors and drugs within the scaffolds to ensure localized drug release and enhance vascularization of the organ by attracting blood vessels to the site of implantation.

  2. Preliminary Thermal Hydraulic Analyses of the Conceptual Core Models with Tubular Type Fuel Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Hee Taek; Park, Jong Hark; Park, Cheol

    2006-11-15

    A new research reactor (AHR, Advanced HANARO Reactor) based on the HANARO has being conceptually developed for the future needs of research reactors. A tubular type fuel was considered as one of the fuel options of the AHR. A tubular type fuel assembly has several curved fuel plates arranged with a constant small gap to build up cooling channels, which is very similar to an annulus pipe with many layers. This report presents the preliminary analysis of thermal hydraulic characteristics and safety margins for three conceptual core models using tubular fuel assemblies. Four design criteria, which are the fuel temperature, ONB (Onset of Nucleate Boiling) margin, minimum DNBR (Departure from Nucleate Boiling Ratio) and OFIR (Onset of Flow Instability Ratio), were investigated along with various core flow velocities in the normal operating conditions. And the primary coolant flow rate based a conceptual core model was suggested as a design information for the process design of the primary cooling system. The computational fluid dynamics analysis was also carried out to evaluate the coolant velocity distributions between tubular channels and the pressure drop characteristics of the tubular fuel assembly.

  3. Tubular carcinoma of the breast: prognosis and response to adjuvant systemic therapy.

    Science.gov (United States)

    Kitchen, P R; Smith, T H; Henderson, M A; Goldhirsch, A; Castiglione-Gertsch, M; Coates, A S; Gusterson, B; Brown, R W; Gelber, R D; Collins, J P

    2001-01-01

    Tubular carcinoma of the breast is an uncommon and usually small tumour, and is thought to have a favourable prognosis. The present study examined the long-term prognosis of patients with tubular breast carcinoma and the roles of axillary dissection and adjuvant therapy. Eighty-six tubular cases were identified from a large worldwide database of 9520 breast carcinoma patients entered into randomized adjuvant therapy trials run by the International Breast Cancer Study Group from 1978 to 1999. These patients were followed for a median of 12 years. Forty-two (49%) cases were node-positive, of which 33 (79%) had 1-3 nodes involved. Ten (32%) of the 31 smaller tumours (survival (P = 0.006) and survival (P survival was similar for node-positive and node-negative tubular carcinoma. Overall, 71 patients (83%) received some form of adjuvant systemic therapy. Of the 86 cases, 43 (50%) received more than one course of chemotherapy. There was an 85% decrease in the risk of death for patients who received more than one course of chemotherapy compared to those who did not (hazard ratio 0.15, 95% confidence interval (CI): 0.03-0.82; P = 0.03). Compared to other histological types of breast cancer, tubular carcinoma has a better long-term prognosis. Adjuvant chemotherapy may further improve prognosis and involvement of axillary nodes may not be an indicator for early death due to breast carcinoma.

  4. Preoperative diagnosis of tubular adenoma of breast - 10 years of experience

    Directory of Open Access Journals (Sweden)

    Sanjay Sengupta

    2014-01-01

    Full Text Available Background: Tubular adenomas are rare benign neoplasms of female breast affecting women, predominantly of child-bearing age group. Definitive diagnosis of this tumor is usually achieved after histopathological study. Clinical, radiological, and even cytological features are often insufficient for accurate diagnosis. Aim: The aim of the present study was planned to analyze clinical and radiological features of histologically confirmed cases of tubular adenoma of breast to find out a clue for accurate preoperative cytological diagnosis. Materials and Methods: In our 10-year research program, all histologically confirmed tubular adenoma cases of breast were studied. Clinico-radio-cytological features, if available, were analyzed and tabulated. Results: Thirty-three cases of tubular adenoma of breast were studied. Radiological and cytological assessments are available for 12 and 26 cases, respectively. Tubular adenoma could be diagnosed in only two cases (7.7% by cytological assessment, but in none by radiological assessment. Conclusions: Clinico-cyto-radiological assessment could identify the benign nature of the tumors in most cases, but final confirmation was possible only after histopathological study.

  5. Polydopamine-coated open tubular column for the separation of proteins by capillary electrochromatography.

    Science.gov (United States)

    Xiao, Xing; Wang, Wentao; Chen, Jia; Jia, Li

    2015-08-01

    The separation and determination of proteins in food is an important aspect in food industry. Inspired by the self-polymerization of dopamine under alkaline conditions and the natural adhesive properties of polydopamine, in this paper, a simple and economical method was developed for the preparation of polydopamine-coated open tubular column, in which ammonium persulfate was used as the source of oxygen to induce and facilitate the polymerization of dopamine to form polydopamine. In comparison with a naked fused-silica capillary, the direction and magnitude of the electro-osmotic flow of the as-prepared polydopamine-coated open tubular column could be manipulated by varying the pH values of background solutions due to the existence of amine and phenolic hydroxyl groups on polydopamine coating. The surface morphology of the polydopamine-coated open tubular column was studied by scanning electron microscopy, and the thickness of polydopamine coating was 106 nm. The performance of the polydopamine-coated open tubular column was validated by analysis of proteins. The relative standard deviations of migration times of proteins representing run-to-run, day-to-day, and column-to-column were less than 3.5%. In addition, the feasibility of the polydopamine-coated open tubular column for real samples was verified by the separation of proteins in chicken egg white and pure milk. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. A new minimally invasive tubular brain retractor system for surgery of deep intracerebral hematoma

    Directory of Open Access Journals (Sweden)

    Yad R Yadav

    2011-01-01

    Full Text Available Access to deep-seated brain lesions with traditional fixed and rigid brain retractors can be difficult without causing significant trauma to the surrounding brain. Tubular retractors offer an advantage of low retracting pressure. We developed a new inexpensive and simple tubular retractor which requires very small cortisectomy. The new tubular retractor was made up of silicone with inner diameter of 15, 18 and 23 mm and outer diameter of 17, 20 and 25 mm, respectively. This tube (1 mm thick was cut in longitudinal direction. It was folded to make a small-diameter tube so that it could be introduced through a small cortisectomy. Margins of cortisectomy were gently and slowly retracted by Killian nasal speculum. Folded retractor, held by tissue forceps, was introduced inside the opened Killian nasal speculum. Tissue forceps and nasal speculum were removed leaving tubular retractor in place, which comes back to its normal tubular configuration after release. Surgery was performed using rigid Karl Storz 0° telescope (30 cm long and 4 mm in diameter or microscope. Near-total removals of intracerebral hematomas, 37 hypertensive and 3 traumatic, was done using this retractor without any complication.

  7. BI-LAYER HYBRID BIOCOMPOSITES: CHEMICAL RESISTANT AND PHYSICAL PROPERTIES

    Directory of Open Access Journals (Sweden)

    Mohammad Jawaid,

    2012-02-01

    Full Text Available Bi-layer hybrid biocomposites were fabricated by hand lay-up technique by reinforcing oil palm empty fruit bunch (EFB and jute fibre mats with epoxy matrix. Hybrid composites were prepared by varying the relative weight fraction of the two fibres. The physical (void content, density, dimensional stability, and chemical resistant properties of hybrid composites were evaluated. When the jute fibre loading increased in hybrid composites, physical and chemical resistant properties of hybrid composites were enhanced. Void content of hybrid composites decreased with an increase in jute fibre loading because jute fibres showed better fibre/matrix interface bonding, which leads to a reduction in voids. The density of hybrid composite increased as the quantity of jute fibre loading increased. The hybridization of the jute fibres with EFB composite improved the dimensional stability of the hybrid composites. The performance of hybrid composites towards chemical reagents improved with an increase in jute fibre loading as compared to the EFB composite. The combination of oil palm EFB/jute fibres with epoxy matrix produced hybrid biocomposites material that is competitive to synthetic composites.

  8. Hybrid Isolation Forest - Application to Intrusion Detection

    OpenAIRE

    Marteau, Pierre-François; Soheily-Khah, Saeid; Béchet, Nicolas

    2017-01-01

    From the identification of a drawback in the Isolation Forest (IF) algorithm that limits its use in the scope of anomaly detection, we propose two extensions that allow to firstly overcome the previously mention limitation and secondly to provide it with some supervised learning capability. The resulting Hybrid Isolation Forest (HIF) that we propose is first evaluated on a synthetic dataset to analyze the effect of the new meta-parameters that are introduced and verify that the addressed limi...

  9. Asynchronous meiosis in Cucumis hystrix-cucumber synthetic tetraploids resulting in low male fertility

    Science.gov (United States)

    Wide hybridization is an important tool for crop improvement. Recently, we successfully developed a synthetic allotetraploid from interspecific cross between cucumber and its relative Cucumis hystrix-(2n = 2x =24) followed by chemical induction of chromosome doubling. The resulting allotetraploid wa...

  10. Graphene Hybrid Materials in Gas Sensing Applications †

    Science.gov (United States)

    Latif, Usman; Dickert, Franz L.

    2015-01-01

    Graphene, a two dimensional structure of carbon atoms, has been widely used as a material for gas sensing applications because of its large surface area, excellent conductivity, and ease of functionalization. This article reviews the most recent advances in graphene hybrid materials developed for gas sensing applications. In this review, synthetic approaches to fabricate graphene sensors, the nano structures of hybrid materials, and their sensing mechanism are presented. Future perspectives of this rapidly growing field are also discussed. PMID:26690156

  11. Hybrid Gear

    Science.gov (United States)

    Handschuh, Robert F. (Inventor); Roberts, Gary D. (Inventor)

    2016-01-01

    A hybrid gear consisting of metallic outer rim with gear teeth and metallic hub in combination with a composite lay up between the shaft interface (hub) and gear tooth rim is described. The composite lay-up lightens the gear member while having similar torque carrying capability and it attenuates the impact loading driven noise/vibration that is typical in gear systems. The gear has the same operational capability with respect to shaft speed, torque, and temperature as an all-metallic gear as used in aerospace gear design.

  12. Hybrid Qualifications

    DEFF Research Database (Denmark)

    has turned out as a major focus of European education and training policies and certainly is a crucial principle underlying the European Qualifications Framework (EQF). In this context, «hybrid qualifications» (HQ) may be seen as an interesting approach to tackle these challenges as they serve «two...... masters», i.e. by producing skills for the labour market and enabling individuals to progress more or less directly to higher education. The specific focus of this book is placed on conditions, structures and processes which help to combine VET with qualifications leading into higher education...

  13. Freedom and Responsibility in Synthetic Genomics: The Synthetic Yeast Project.

    Science.gov (United States)

    Sliva, Anna; Yang, Huanming; Boeke, Jef D; Mathews, Debra J H

    2015-08-01

    First introduced in 2011, the Synthetic Yeast Genome (Sc2.0) PROJECT is a large international synthetic genomics project that will culminate in the first eukaryotic cell (Saccharomyces cerevisiae) with a fully synthetic genome. With collaborators from across the globe and from a range of institutions spanning from do-it-yourself biology (DIYbio) to commercial enterprises, it is important that all scientists working on this project are cognizant of the ethical and policy issues associated with this field of research and operate under a common set of principles. In this commentary, we survey the current ethics and regulatory landscape of synthetic biology and present the Sc2.0 Statement of Ethics and Governance to which all members of the project adhere. This statement focuses on four aspects of the Sc2.0 PROJECT: societal benefit, intellectual property, safety, and self-governance. We propose that such project-level agreements are an important, valuable, and flexible model of self-regulation for similar global, large-scale synthetic biology projects in order to maximize the benefits and minimize potential harms. Copyright © 2015 by the Genetics Society of America.

  14. Freedom and Responsibility in Synthetic Genomics: The Synthetic Yeast Project

    Science.gov (United States)

    Sliva, Anna; Yang, Huanming; Boeke, Jef D.; Mathews, Debra J. H.

    2015-01-01

    First introduced in 2011, the Synthetic Yeast Genome (Sc2.0) Project is a large international synthetic genomics project that will culminate in the first eukaryotic cell (Saccharomyces cerevisiae) with a fully synthetic genome. With collaborators from across the globe and from a range of institutions spanning from do-it-yourself biology (DIYbio) to commercial enterprises, it is important that all scientists working on this project are cognizant of the ethical and policy issues associated with this field of research and operate under a common set of principles. In this commentary, we survey the current ethics and regulatory landscape of synthetic biology and present the Sc2.0 Statement of Ethics and Governance to which all members of the project adhere. This statement focuses on four aspects of the Sc2.0 Project: societal benefit, intellectual property, safety, and self-governance. We propose that such project-level agreements are an important, valuable, and flexible model of self-regulation for similar global, large-scale synthetic biology projects in order to maximize the benefits and minimize potential harms. PMID:26272997

  15. Effects of Synthetic Serum Supplementation in Sperm Preparation Media on Sperm Capacitation and Function Test Results

    Directory of Open Access Journals (Sweden)

    Ying-Fu Shih

    2016-01-01

    Full Text Available Albumin supplementation of culture media induces sperm capacitation in assisted reproduction technique cycles. Synthetic serum supplementation is clinically used to replace albumin for preventing transmission of infectious agents. However, the effects of synthetic serum supplementation on sperm capacitation have rarely been investigated. Spermatozoa from 30 men with normal basic semen analysis results were collected, divided into five aliquots, and cultured in capacitating conditions in four combinations of two synthetic serum supplements, serum substitute supplement (SSS and serum protein substitute (SPS, and two fertilization media, Quinns Advantage™ Fertilization (QF and human tubular fluid (HTF media. Reactive oxygen species (ROS levels in spermatozoa were measured through chemiluminescence. Furthermore, acrosome reaction and western blotting for tyrosine phosphorylation were used to evaluate sperm capacitation. HTF+SSS had significantly higher ROS levels than QF+SPS did (11,725 ± 1,172 versus 6,278 ± 864 relative light units. In addition, the spermatozoa cultured in QF+SPS had lower motility, acrosome reaction rates, and tyrosine phosphorylation levels compared with those cultured in HTF+SSS. In conclusion, the effects of synthetic serum supplementation on sperm capacitation varied according to the combination of media. These differences may lead to variations in spermatozoon ROS levels, thus affecting sperm function test results.

  16. Inspection system for welded tubular joint based on ultrasonic phased array

    Institute of Scientific and Technical Information of China (English)

    Hao Guangping; Deng Zongquan; Shan Baohua; Yu Weizhen; Li Lifang

    2010-01-01

    A manual inspection of large-diameter tubular joints is difficult. As a result a scanner with three degrees of freedom (DOFs) was developed based on the scanning principle of ultrasonic phased array. The weld tracing is realized by a 2D0F motion of scanner. The pose of ultrasonic probe is controlled by the third one. The control strategy is put forward based on a programmable multi-axis controller. Four kinds of scanning modes can be implemented simultaneously employing this ultrasonic inspection system. Experiments on reference blocks of tubular joints reveal that the automatic ultrasonic phased array inspection system has the same inspection accuracy as a manual ultrasonic inspection. This system is superior to the manual ultrasonic system in terms of reliability and repeatability. The artificial defects of weld at tubular joint can be detected accurately with the presented inspection system.

  17. Species diversity regarding the presence of proximal tubular progenitor cells of the kidney

    Directory of Open Access Journals (Sweden)

    J. Hansson

    2016-02-01

    Full Text Available The cellular source for tubular regeneration following kidney injury is a matter of dispute, with reports suggesting a stem or progenitor cells as the regeneration source while linage tracing studies in mice seemingly favor the classical theory, where regeneration is performed by randomly surviving cells. We, and others have previously described a scattered cell population localized to the tubules of human kidney, which increases in number following injury. Here we have characterized the species distribution of these proximal tubular progenitor cells (PTPCs in kidney tissue from chimpanzee, pig, rat and mouse using a set of human PTPC markers. We detected PTPCs in chimpanzee and pig kidneys, but not in mouse tissue. Also, subjecting mice to the unilateral urethral obstruction model, caused clear signs of tubular injury, but failed to induce the PTPC phenotype in renal tubules.

  18. Overall renal and tubular function during infusion of amino acids in normal man

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal; Hansen, J M; Ladefoged, S D

    1990-01-01

    1. Amino acids have been used to test renal reserve filtration capacity. Previous studies suggest that amino acids increase glomerular filtration rate (GFR) by reducing distal tubular flow and tubuloglomerular feedback activity. 2. Glomerular function and the renal tubular handling of sodium during...... infusion of amino acids was studied in 12 normal volunteers. 3. Clearance of sodium (CNa) was unchanged. Effective renal plasma flow increased slightly, but significantly, by 9% (P less than 0.05). GFR was increased by 13% (P less than 0.001). Clearance of lithium (CLi) (used as an index of proximal...... tubular outflow) increased by 38% (P less than 0.001). Calculated absolute proximal reabsorption (GFR-CLi) remained unchanged. Fractional proximal reabsorption [1-(CLi/GFR)] was decreased by 10% (P less than 0.001). Calculated absolute distal sodium reabsorption [(CLi-CNa) x PNa, where PNa is plasma...

  19. Dynamic responses of concrete-filled steel tubular member under axial compression considering creep effect

    Science.gov (United States)

    Jiang, X. T.; Wang, Y. D.; Dai, C. H.; Ding, M.

    2017-08-01

    The finite element model of concrete-filled steel tubular member was established by the numerical analysis software considering material nonlinearity to analyze concrete creep effect on the dynamic responses of the member under axial compression and lateral impact. In the model, the constitutive model of core concrete is the plastic damage model, that of steel is the Von Mises yield criterion and kinematic hardening model, and the creep effect at different ages is equivalent to the change of concrete elastic modulus. Then the dynamic responses of concrete-filled steel tubular member considering creep effects was simulated, and the effects of creep on contact time, impact load, deflection, stress and strain were discussed. The fruits provide a scientific basis for the design of the impact resistance of concrete filled steel tubular members.

  20. Modification of tubular ceramic membranes with carbon nanotubes using catalytic chemical vapor deposition.

    Science.gov (United States)

    Tran, Duc Trung; Thieffry, Guillemette; Jacob, Matthieu; Batiot-Dupeyrat, Catherine; Teychene, Benoit

    2015-01-01

    In this study, carbon nanotubes (CNTs) were successfully grown on tubular ceramic membranes using the catalytic chemical vapor deposition (CCVD) method. CNTs were synthesized at 650°C for 3-6 h under a 120 mL min(-1) flow of C2H6 on ceramic membranes impregnated with iron salt. The synthesis procedure was beforehand optimized in terms of catalyst amount, impregnation duration and reaction temperature, using small pieces of tubular ceramic membranes. The yield, size and structure of the CNTs produced were characterized using thermogravimetric analysis and microscopic imaging techniques. Afterwards, preliminary filtration tests with alginate and phenol were performed on two modified tubular membranes. The results indicate that the addition of CNTs on the membrane material increased the permeability of ceramic membrane and its ability to reject alginate and adsorb phenol, yet decreased its fouling resistance.

  1. Population analysis of the cingulum bundle using the tubular surface model for schizophrenia detection

    Science.gov (United States)

    Mohan, Vandana; Sundaramoorthi, Ganesh; Kubicki, Marek; Terry, Douglas; Tannenbaum, Allen

    2010-03-01

    We propose a novel framework for population analysis of DW-MRI data using the Tubular Surface Model. We focus on the Cingulum Bundle (CB) - a major tract for the Limbic System and the main connection of the Cingulate Gyrus, which has been associated with several aspects of Schizophrenia symptomatology. The Tubular Surface Model represents a tubular surface as a center-line with an associated radius function. It provides a natural way to sample statistics along the length of the fiber bundle and reduces the registration of fiber bundle surfaces to that of 4D curves. We apply our framework to a population of 20 subjects (10 normal, 10 schizophrenic) and obtain excellent results with neural network based classification (90% sensitivity, 95% specificity) as well as unsupervised clustering (k-means). Further, we apply statistical analysis to the feature data and characterize the discrimination ability of local regions of the CB, as a step towards localizing CB regions most relevant to Schizophrenia.

  2. Overall renal and tubular function during infusion of amino acids in normal man

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal; Hansen, J M; Ladefoged, S D

    1990-01-01

    1. Amino acids have been used to test renal reserve filtration capacity. Previous studies suggest that amino acids increase glomerular filtration rate (GFR) by reducing distal tubular flow and tubuloglomerular feedback activity. 2. Glomerular function and the renal tubular handling of sodium during...... infusion of amino acids was studied in 12 normal volunteers. 3. Clearance of sodium (CNa) was unchanged. Effective renal plasma flow increased slightly, but significantly, by 9% (P less than 0.05). GFR was increased by 13% (P less than 0.001). Clearance of lithium (CLi) (used as an index of proximal...... tubular outflow) increased by 38% (P less than 0.001). Calculated absolute proximal reabsorption (GFR-CLi) remained unchanged. Fractional proximal reabsorption [1-(CLi/GFR)] was decreased by 10% (P less than 0.001). Calculated absolute distal sodium reabsorption [(CLi-CNa) x PNa, where PNa is plasma...

  3. Micro-Drilling of Polymer Tubular Ultramicroelectrode Arrays for Electrochemical Sensors

    Directory of Open Access Journals (Sweden)

    Niels B. Larsen

    2013-05-01

    Full Text Available We present a reproducible fast prototyping procedure based on micro-drilling to produce homogeneous tubular ultramicroelectrode arrays made from poly(3,4-ethylenedioxythiophene (PEDOT, a conductive polymer. Arrays of Ø 100 µm tubular electrodes each having a height of 0.37 ± 0.06 µm were reproducibly fabricated. The electrode dimensions were analyzed by SEM after deposition of silver dendrites to visualize the electroactive electrode area. The electrochemical applicability of the electrodes was demonstrated by voltammetric and amperometric detection of ferri-/ferrocyanide. Recorded signals were in agreement with results from finite element modelling of the system. The tubular PEDOT ultramicroelectrode arrays were modified by prussian blue to enable the detection of hydrogen peroxide. A linear sensor response was demonstrated for hydrogen peroxide concentrations from 0.1 mM to 1 mM.

  4. Micro-drilling of polymer tubular ultramicroelectrode arrays for electrochemical sensors

    DEFF Research Database (Denmark)

    Kafka, Jan Robert; Skaarup, Steen; Geschke, Oliver

    2013-01-01

    We present a reproducible fast prototyping procedure based on micro-drilling to produce homogeneous tubular ultramicroelectrode arrays made from poly(3,4-ethylenedioxythiophene) (PEDOT), a conductive polymer. Arrays of Ø 100 μm tubular electrodes each having a height of 0.37 ± 0.06 μm were...... reproducibly fabricated. The electrode dimensions were analyzed by SEM after deposition of silver dendrites to visualize the electroactive electrode area. The electrochemical applicability of the electrodes was demonstrated by voltammetric and amperometric detection of ferri-/ferrocyanide. Recorded signals...... were in agreement with results from finite element modelling of the system. The tubular PEDOT ultramicroelectrode arrays were modified by prussian blue to enable the detection of hydrogen peroxide. A linear sensor response was demonstrated for hydrogen peroxide concentrations from 0.1 mM to 1 mM....

  5. Micro-drilling of polymer tubular ultramicroelectrode arrays for electrochemical sensors.

    Science.gov (United States)

    Kafka, Jan; Skaarup, Steen; Geschke, Oliver; Larsen, Niels B

    2013-05-14

    We present a reproducible fast prototyping procedure based on micro-drilling to produce homogeneous tubular ultramicroelectrode arrays made from poly(3,4-ethylenedioxythiophene) (PEDOT), a conductive polymer. Arrays of Ø 100 µm tubular electrodes each having a height of 0.37 ± 0.06 µm were reproducibly fabricated. The electrode dimensions were analyzed by SEM after deposition of silver dendrites to visualize the electroactive electrode area. The electrochemical applicability of the electrodes was demonstrated by voltammetric and amperometric detection of ferri-/ferrocyanide. Recorded signals were in agreement with results from finite element modelling of the system. The tubular PEDOT ultramicroelectrode arrays were modified by prussian blue to enable the detection of hydrogen peroxide. A linear sensor response was demonstrated for hydrogen peroxide concentrations from 0.1 mM to 1 mM.

  6. Penile urethra replacement with autologous cell-seeded tubularized collagen matrices.

    Science.gov (United States)

    De Filippo, Roger E; Kornitzer, Benjamin S; Yoo, James J; Atala, Anthony

    2015-03-01

    Acellular collagen matrices have been used as an onlay material for urethral reconstruction. However, cell-seeded matrices have been recommended for tubularized urethral repairs. In this study we investigated whether long segmental penile urethral replacement using autologous cell-seeded tubularized collagen-based matrix is feasible. Autologous bladder epithelial and smooth muscle cells from nine male rabbits were grown and seeded onto preconfigured tubular matrices constructed from decellularized bladder matrices obtained from lamina propria. The entire anterior penile urethra was resected in 15 rabbits. Urethroplasties were performed with tubularized matrices seeded with cells in nine animals, and with matrices without cells in six. Serial urethrograms were performed at 1, 3 and 6 months. Retrieved urethral tissues were analysed using histo- and immunohistochemistry, western blot analyses and organ bath studies. The urethrograms showed that animals implanted with cell-seeded matrices maintained a wide urethral calibre without strictures. In contrast, the urethras with unseeded scaffolds collapsed and developed strictures. Histologically, a transitional cell layer surrounded by muscle was observed in the cell-seeded constructs. The epithelial and smooth muscle phenotypes were confirmed with AE1/AE3 and α-actin antibodies. Organ bath studies of the neourethras confirmed both physiological contractility and the presence of neurotransmitters. Tubularized collagen matrices seeded with autologous cells can be used successfully for long segmental penile urethra replacement, while implantation of tubularized collagen matrices without cells leads to poor tissue development and stricture formation. The cell-seeded collagen matrices are able to form new tissue, which is histologically similar to native urethra.

  7. Renal tubular dysfunction with nephrocalcinosis in a patient with beta thalassemia minor

    Directory of Open Access Journals (Sweden)

    Prabahar Murugesan

    2008-01-01

    Full Text Available Thalassemia is a hereditary anemia resulting from defect in hemoglobin production. Beta thalassemia is due to impaired production of beta globin chains, leading to a relative excess of alpha globin chains. The term beta thalassemia minor is used to describe heterozygotes, who carry one normal beta globin allele and one beta thalassemic allele. The vast majority of these patients are asymptomatic. However, a variety of renal tubular abnormalities including hypercalciuria, hypo-magnesemia with renal magnesium wasting, decreased tubular absorption of phosphorus, hypo-uricemia with renal uric acid wasting, renal glycosuria and tubular proteinuria have been described even in patients with beta thalassemia minor. We here in report a 24-year old female patient who was found to have thalassemia minor and nephrocalcinosis with evidence of renal tubular dysfunction. Investigations revealed normal renal function, hypercalciuria, reduced tubular reabsorption of phos-phorus, hypomagnesemia and renal magnesium wasting. Screening for aminoaciduria was found to be negative. An acid loading test revealed normal urinary acidification. Ultrasonogram of the abdomen revealed nephrocalcinosis and splenomegaly. Detailed work up for anemia showed normal white cell and platelet count while peripheral smear showed microcytic hypochromic anemia with few target cells. Hemoglobin electrophoresis revealed hemoglobin A of 92%, hemoglobin A2 of 6.2% and hemo-globin F of 1.8% consistent with beta thalassemia minor. Her parental screening was normal. A diag-nosis of beta thalassemia minor with renal tubular dysfunction was made and the patient was started on thiazide diuretics to reduce hypercalciuria and advised regular follow-up.

  8. Interferon-γ Reduces the Proliferation of Primed Human Renal Tubular Cells

    Directory of Open Access Journals (Sweden)

    Omar García-Sánchez

    2014-01-01

    Full Text Available Background/Aims: Chronic kidney disease (CKD is a progressive deterioration of the kidney function, which may eventually lead to renal failure and the need for dialysis or kidney transplant. Whether initiated in the glomeruli or the tubuli, CKD is characterized by progressive nephron loss, for which the process of tubular deletion is of key importance. Tubular deletion results from tubular epithelial cell death and defective repair, leading to scarring of the renal parenchyma. Several cytokines and signaling pathways, including transforming growth factor-β (TGF-β and the Fas pathway, have been shown to participate in vivo in tubular cell death. However, there is some controversy about their mode of action, since a direct effect on normal tubular cells has not been demonstrated. We hypothesized that epithelial cells would require specific priming to become sensitive to TGF-β or Fas stimulation and that this priming would be brought about by specific mediators found in the pathological scenario. Methods: Herein we studied whether the combined effect of several stimuli known to take part in CKD progression, namely TGF-β, tumor necrosis factor-α, interferon-γ (IFN-γ, and Fas stimulation, on primed resistant human tubular cells caused cell death or reduced proliferation. Results: We demonstrate that these cytokines have no synergistic effect on the proliferation or viability of human kidney (HK2 cells. We also demonstrate that IFN-γ, but not the other stimuli, reduces the proliferation of cycloheximide-primed HK2 cells without affecting their viability. Conclusion: Our results point at a potentially important role of IFN-γ in defective repair, leading to nephron loss during CKD.

  9. Meeting Report: Synthetic Biology Jamboree for Undergraduates

    Science.gov (United States)

    Campbell, A. Malcolm

    2005-01-01

    The field of synthetic biology (the name is derived from an analogy to synthetic chemistry) has recognized itself as a "field" only since about 2002. Synthetic biology has gotten some high-profile attention recently, but most people are not aware the field even exists. Synthetic biologists apply engineering principles to genomic circuits to…

  10. Meeting Report: Synthetic Biology Jamboree for Undergraduates

    Science.gov (United States)

    Campbell, A. Malcolm

    2005-01-01

    The field of synthetic biology (the name is derived from an analogy to synthetic chemistry) has recognized itself as a "field" only since about 2002. Synthetic biology has gotten some high-profile attention recently, but most people are not aware the field even exists. Synthetic biologists apply engineering principles to genomic circuits to…

  11. Accelerated Senescence and Enhanced Disease Resistance in Hybrid Chlorosis Lines Derived from Interspecific Crosses between Tetraploid Wheat and Aegilops tauschii

    OpenAIRE

    Hiroki Nakano; Nobuyuki Mizuno; Yukio Tosa; Kentaro Yoshida; Pyoyun Park; Shigeo Takumi

    2015-01-01

    Hybrid chlorosis, a type of hybrid incompatibility, has frequently been reported in inter- and intraspecific crosses of allopolyploid wheat. In a previous study, we reported some types of growth abnormalities such as hybrid necrosis and observed hybrid chlorosis with mild or severe abnormalities in wheat triploids obtained in crosses between tetraploid wheat cultivar Langdon and four Ae. tauschii accessions and in their derived synthetic hexaploids. However, the molecular mechanisms underlyin...

  12. Intuitionistic hybrid logic

    DEFF Research Database (Denmark)

    Braüner, Torben

    2011-01-01

    Intuitionistic hybrid logic is hybrid modal logic over an intuitionistic logic basis instead of a classical logical basis. In this short paper we introduce intuitionistic hybrid logic and we give a survey of work in the area.......Intuitionistic hybrid logic is hybrid modal logic over an intuitionistic logic basis instead of a classical logical basis. In this short paper we introduce intuitionistic hybrid logic and we give a survey of work in the area....

  13. Continuity Controlled Hybrid Automata

    OpenAIRE

    Bergstra, J. A.; Middelburg, C.A.

    2004-01-01

    We investigate the connections between the process algebra for hybrid systems of Bergstra and Middelburg and the formalism of hybrid automata of Henzinger et al. We give interpretations of hybrid automata in the process algebra for hybrid systems and compare them with the standard interpretation of hybrid automata as timed transition systems. We also relate the synchronized product operator on hybrid automata to the parallel composition operator of the process algebra. It turns out that the f...

  14. Control theory meets synthetic biology.

    Science.gov (United States)

    Del Vecchio, Domitilla; Dy, Aaron J; Qian, Yili

    2016-07-01

    The past several years have witnessed an increased presence of control theoretic concepts in synthetic biology. This review presents an organized summary of how these control design concepts have been applied to tackle a variety of problems faced when building synthetic biomolecular circuits in living cells. In particular, we describe success stories that demonstrate how simple or more elaborate control design methods can be used to make the behaviour of synthetic genetic circuits within a single cell or across a cell population more reliable, predictable and robust to perturbations. The description especially highlights technical challenges that uniquely arise from the need to implement control designs within a new hardware setting, along with implemented or proposed solutions. Some engineering solutions employing complex feedback control schemes are also described, which, however, still require a deeper theoretical analysis of stability, performance and robustness properties. Overall, this paper should help synthetic biologists become familiar with feedback control concepts as they can be used in their application area. At the same time, it should provide some domain knowledge to control theorists who wish to enter the rising and exciting field of synthetic biology.

  15. Control theory meets synthetic biology

    Science.gov (United States)

    2016-01-01

    The past several years have witnessed an increased presence of control theoretic concepts in synthetic biology. This review presents an organized summary of how these control design concepts have been applied to tackle a variety of problems faced when building synthetic biomolecular circuits in living cells. In particular, we describe success stories that demonstrate how simple or more elaborate control design methods can be used to make the behaviour of synthetic genetic circuits within a single cell or across a cell population more reliable, predictable and robust to perturbations. The description especially highlights technical challenges that uniquely arise from the need to implement control designs within a new hardware setting, along with implemented or proposed solutions. Some engineering solutions employing complex feedback control schemes are also described, which, however, still require a deeper theoretical analysis of stability, performance and robustness properties. Overall, this paper should help synthetic biologists become familiar with feedback control concepts as they can be used in their application area. At the same time, it should provide some domain knowledge to control theorists who wish to enter the rising and exciting field of synthetic biology. PMID:27440256

  16. Mesenchymal stem cells modulate albumin-induced renal tubular inflammation and fibrosis.

    Directory of Open Access Journals (Sweden)

    Hao Jia Wu

    Full Text Available Bone marrow-derived mesenchymal stem cells (BM-MSCs have recently shown promise as a therapeutic tool in various types of chronic kidney disease (CKD models. However, the mechanism of action is incompletely understood. As renal prognosis in CKD is largely determined by the degree of renal tubular injury that correlates with residual proteinuria, we hypothesized that BM-MSCs may exert modulatory effects on renal tubular inflammation and epithelial-to-mesenchymal transition (EMT under a protein-overloaded milieu. Using a co-culture model of human proximal tubular epithelial cells (PTECs and BM-MSCs, we showed that concomitant stimulation of BM-MSCs by albumin excess was a prerequisite for them to attenuate albumin-induced IL-6, IL-8, TNF-α, CCL-2, CCL-5 overexpression in PTECs, which was partly mediated via deactivation of tubular NF-κB signaling. In addition, albumin induced tubular EMT, as shown by E-cadherin loss and α-SMA, FN and collagen IV overexpression, was also prevented by BM-MSC co-culture. Albumin-overloaded BM-MSCs per se retained their tri-lineage differentiation capacity and overexpressed hepatocyte growth factor (HGF and TNFα-stimulating gene (TSG-6 via P38 and NF-κB signaling. Albumin-induced tubular CCL-2, CCL-5 and TNF-α overexpression were suppressed by recombinant HGF treatment, while the upregulation of α-SMA, FN and collagen IV was attenuated by recombinant TSG-6. Neutralizing HGF and TSG-6 abolished the anti-inflammatory and anti-EMT effects of BM-MSC co-culture in albumin-induced PTECs, respectively. In vivo, albumin-overloaded mice treated with mouse BM-MSCs had markedly reduced BUN, tubular CCL-2 and CCL-5 expression, α-SMA and collagen IV accumulation independent of changes in proteinuria. These data suggest anti-inflammatory and anti-fibrotic roles of BM-MSCs on renal tubular cells under a protein overloaded condition, probably mediated via the paracrine action of HGF and TSG-6.

  17. Effects of receptor-mediated endocytosis and tubular protein composition on volume retention in experimental glomerulonephritis

    DEFF Research Database (Denmark)

    Kastner, Christian; Pohl, Marcus; Sendeski, Mauricio

    2009-01-01

    Human glomerulonephritis (GN) is characterized by sustained proteinuria, sodium retention, hypertension, and edema formation. Increasing quantities of filtered protein enter the renal tubule, where they may alter epithelial transport functions. Exaggerated endocytosis and consequent protein overl...... mechanism of channel activation which may involve the action of filtered plasma proteases....... and channels involved in volume regulation were altered in GN, and 2) proximal tubular endocytosis may influence locally as well as downstream expressed tubular transporters and channels. Effects of anti-glomerular basement membrane GN were studied in controls and megalin-deficient mice with blunted proximal...

  18. The influence of angiotensin-converting enzyme inhibition on renal tubular function in progressive chronic nephropathy

    DEFF Research Database (Denmark)

    Kamper, A L; Holstein-Rathlou, N H; Leyssac, P P

    1996-01-01

    The influence of angiotensin-converting enzyme (ACE) inhibition on renal tubular function in progressive chronic nephropathy was investigated in 69 patients by the lithium clearance (C(Li)) method. Studies were done repeatedly for up to 2 years during a controlled trial on the effect of enalapril....... In the conventional group, the fractional clearances of these three plasma proteins all increased. It is concluded that in progressive chronic nephropathy ACE-inhibitor treatment was associated with different adaptive tubular changes in the handling of sodium, water, and protein compared with conventional...

  19. Tubular and glomerular injury in diabetes and the impact of ACE inhibition

    DEFF Research Database (Denmark)

    Nielsen, Stine E; Sugaya, Takeshi; Tarnow, Lise

    2009-01-01

    OBJECTIVE: We studied tubular and glomerular damage in type 1 diabetic patients by measuring urinary-liver fatty acid binding protein (U-LFABP) and albuminuria. Subsequently, we evaluated the effect of ACE inhibition on U-LFABP in patients with diabetic nephropathy. RESEARCH DESIGN AND METHODS: We......, 46, and 40% with increasing doses of lisinopril (NS). CONCLUSIONS: An early and progressive increase in tubulointerstitial damage as reflected by increased U-LFABP levels occurs in type 1 diabetic patients and is associated with albuminuria. Furthermore, ACE inhibition reduces the tubular...

  20. Modelling and experimental verification on concrete-filled steel tubular columns with L or T section

    Institute of Scientific and Technical Information of China (English)

    LU Xilin; LI Xueping; WANG Dan

    2007-01-01

    Concrete-filled steel tubular columns with L or T sections were analyzed in this paper. According to the confin- ing mechanism, the stress-strain constitutive model was put forward, and calculated results were compared with experi- mental records. After that, the hysteretic rules for the in-filled concrete were constructed, aiming at the analysis on the seis- mic behavior of composite members. The simulation analysis was performed by programming it in Fortran. The models in this paper can be applied in the program of time history analysis on tall buildings with concrete-filled steel tubular columns with L or T sections.

  1. Heterogenized homogeneous catalyst. 3. Oxidation of benzaldehyde in a semibatch tubular wall reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, M.C.; Chou, T.C.

    1987-06-01

    The author's previous works showed that the surface of the heterogenized homogeneous catalyst significantly affects both the initiation and termination of free radicals. To minimize free-radical termination by the surface of catalyst and avoid separation of catalyst from the products in a slurry reactor, a tubular reactor was designed in this work. The termination of free radicals by the surface of catalyst is negligible when the tubular wall reactor is used. The selectivity of perbenzoic acid is very high and the maximum yield of perbenzoic acid is 63%. During the experimental period, no leakage of cobaltic ions was found.

  2. Mesenchymal stem cells modulate albumin-induced renal tubular inflammation and fibrosis.

    Science.gov (United States)

    Wu, Hao Jia; Yiu, Wai Han; Li, Rui Xi; Wong, Dickson W L; Leung, Joseph C K; Chan, Loretta Y Y; Zhang, Yuelin; Lian, Qizhou; Lin, Miao; Tse, Hung Fat; Lai, Kar Neng; Tang, Sydney C W

    2014-01-01

    Bone marrow-derived mesenchymal stem cells (BM-MSCs) have recently shown promise as a therapeutic tool in various types of chronic kidney disease (CKD) models. However, the mechanism of action is incompletely understood. As renal prognosis in CKD is largely determined by the degree of renal tubular injury that correlates with residual proteinuria, we hypothesized that BM-MSCs may exert modulatory effects on renal tubular inflammation and epithelial-to-mesenchymal transition (EMT) under a protein-overloaded milieu. Using a co-culture model of human proximal tubular epithelial cells (PTECs) and BM-MSCs, we showed that concomitant stimulation of BM-MSCs by albumin excess was a prerequisite for them to attenuate albumin-induced IL-6, IL-8, TNF-α, CCL-2, CCL-5 overexpression in PTECs, which was partly mediated via deactivation of tubular NF-κB signaling. In addition, albumin induced tubular EMT, as shown by E-cadherin loss and α-SMA, FN and collagen IV overexpression, was also prevented by BM-MSC co-culture. Albumin-overloaded BM-MSCs per se retained their tri-lineage differentiation capacity and overexpressed hepatocyte growth factor (HGF) and TNFα-stimulating gene (TSG)-6 via P38 and NF-κB signaling. Albumin-induced tubular CCL-2, CCL-5 and TNF-α overexpression were suppressed by recombinant HGF treatment, while the upregulation of α-SMA, FN and collagen IV was attenuated by recombinant TSG-6. Neutralizing HGF and TSG-6 abolished the anti-inflammatory and anti-EMT effects of BM-MSC co-culture in albumin-induced PTECs, respectively. In vivo, albumin-overloaded mice treated with mouse BM-MSCs had markedly reduced BUN, tubular CCL-2 and CCL-5 expression, α-SMA and collagen IV accumulation independent of changes in proteinuria. These data suggest anti-inflammatory and anti-fibrotic roles of BM-MSCs on renal tubular cells under a protein overloaded condition, probably mediated via the paracrine action of HGF and TSG-6.

  3. Femtosecond laser fabrication of tubular waveguides in poly(methyl methacrylate).

    Science.gov (United States)

    Zoubir, Arnaud; Lopez, Cedric; Richardson, Martin; Richardson, Kathleen

    2004-08-15

    Femtosecond laser direct writing is employed for the fabrication of buried tubular waveguides in bulk poly(methyl methacrylate). A novel technique using selective chemical etching is presented to resolve the two-dimensional refractive-index profile of the fabrication structures. End-to-end coupling in the waveguides reveals a near-field intensity distribution that results from the superimposition of several propagating modes with different azimuthal symmetries. Mode analysis of the tubular waveguides is performed using the finite-difference method, and the possible propagating mode profiles are compared with the experimental data.

  4. In-Situ TEM-STM Observations of SWCNT Ropes/Tubular Transformations

    Science.gov (United States)

    Sola, F.; Lebron-Colon, M.; Ferreira, P. J.; Fonseca, L. F.; Meador, M. A.; Marin, C.

    2010-01-01

    Single-walled carbon nanotubes (SWCNTs) prepared by the HiPco process were purified using a modified gas phase purification technique. A TEM-STM holder was used to study the morphological changes of SWCNT ropes as a function of applied voltage. Kink formation, buckling behavior, tubular transformation and eventual breakdown of the system were observed. The tubular formation was attributed to a transformation from SWCNT ropes to multi-walled carbon nanotube (MWCNT) structures. It is likely mediated by the patching and tearing mechanism which is promoted primarily by the mobile vacancies generated due to current-induced heating and, to some extent, by electron irradiation.

  5. Study on Defect Detecting and Locating Method of Tubular Cylindrical Conductor

    Directory of Open Access Journals (Sweden)

    Yinchuan Wu

    2013-06-01

    Full Text Available This paper is to present a defect detecting and locating method of tubular cylindrical conductor based on alternating current impedance measurement theory. A defect estimation  can be made through the impedance measurement of some distance on the inner and the outer surfaces of the tubular cylindrical conductor. A defect in the thickness direction can be located by the skin effect influence on impedance and the frequency change in exciting current. The results show that: this method can effectively identify and locate a defect, and therefore should be promoted in the defect detecting of metal materials in other shapes.

  6. Fenómenos de instabilidade em elementos tubulares submetidos à compressão

    OpenAIRE

    Fonseca, E.M.M.; Oliveira, C.A.M de; F. J. M. Q. de Melo

    2005-01-01

    Neste artigo estuda-se o fenómeno de encurvadura por varejamento em elementos tubulares através dos resultados obtidos com um elemento finito de tubo, desenvolvido para análise não linear e com um programa comercial utilizando um elemento de viga com características não-lineares. Efectuaram-se ainda ensaios à temperatura ambiente em elementos tubulares, observando-se experimentalmente que a carga de colapso e o deslocamento lateral da estrutura apresentam comportamentos semelha...

  7. Synthetic Completeness Proofs for Seligman-style Tableau Systems

    DEFF Research Database (Denmark)

    Jørgensen, Klaus Frovin; Blackburn, Patrick Rowan; Bolander, Thomas;

    2016-01-01

    Hybrid logic is a form of modal logic which allows reference to worlds. We can think of it as ‘modal logic with labelling built into the object language’ and various forms of labelled deduction have played a central role in its proof theory. Jerry Seligman’s work [11,12] in which ‘rules involving...... labels’ are rejected in favour of ‘rules for all’ is an interesting exception to this. Seligman’s approach was originally for natural deduction; the authors of the present paper recently extended it to tableau inference [1,2]. Our earlier work was syntactic: we showed completeness by translating between...... Seligman-style and labelled tableaus, but our results only covered the minimal hy- brid logic; in the present paper we provide completeness results for a wider range of hybrid logics and languages. We do so by adapting the synthetic approach to tableau completeness (due to Smullyan, and widely applied...

  8. Analysis and characterization of differential gene expression during rapid trophoblastic elongation in the pig using suppression subtractive hybridization

    Directory of Open Access Journals (Sweden)

    Malayer Jerry R

    2003-02-01

    Full Text Available Abstract During late peri-implantation development, porcine conceptuses undergo a rapid (2–3 hrs morphological transformation from a 10 mm sphere to a thin filamentous form greater than 150 mm in length. Elongation of the conceptus is important for establishing adequate placental surface area needed for embryo and fetal survival throughout gestation. Genes involved with triggering this unique transition in conceptus development are not well defined. Objective of the present study was to utilize suppression subtractive hybridization (SSH to characterize the change in gene expression during conceptus transformation from spherical (8–9 mm to tubular (15–40 mm to early filamentous (>150 mm morphology. Spherical, tubular, and filamentous conceptuses were collected from pregnant gilts and subjected to SSH. Forward and reverse subtractions were performed to identify candidate genes differentially expressed during spherical to tubular and tubular to filamentous transition. A total of 384 transcripts were differentially screened to ensure unique expression. Of the transcripts screened, sequences were obtained for 142 that were confirmed to be differentially expressed among the various morphologies. Gene expression profiles during rapid trophoblastic elongation were generated for selected mRNAs using quantitative real-time PCR. During the transition from tubular to early filamentous conceptuses, s-adenosylhomocysteine hydrolase and heat shock cognate 70 kDa expression were significantly enhanced. A novel unknown gene was isolated and shown to be significantly up-regulated at the onset of rapid trophoblastic elongation and further enhanced in filamentous conceptuses.

  9. Designer Drugs: A Synthetic Catastrophe

    Directory of Open Access Journals (Sweden)

    James Fratantonio

    2015-08-01

    Full Text Available Synthetic stimulants can cause hallucinations, aggressive behaviors, death and are sometimes legal. These substances are sold as plant food and bath salts that are "Not for Human Consumption", therefore skirting the 1986 Federal Analogue Act and giving a false pretense of safety. Studies have proved that these substances are toxic, have a high abuse potential, and are becoming extremely prevalent in the United States. This creates a dilemma for law enforcement agents, hospitals, and substance use disorder treatment centers. Urine Drug Testing is utilized as a clinical diagnostic tool in substance use disorder treatment centers, and the furious pace at which new synthetic stimulants are introduced to the black market are making the detection via urine increasingly difficult. This article will discuss the prevalence, pharmacology and difficulty developing laboratory assays to detect synthetic stimulants.

  10. Synthetic neurosteroids on brain protection

    Directory of Open Access Journals (Sweden)

    Mariana Rey

    2015-01-01

    Full Text Available Neurosteroids, like allopregnanolone and pregnanolone, are endogenous regulators of neuronal excitability. Inside the brain, they are highly selective and potent modulators of GABA A receptor activity. Their anticonvulsant, anesthetics and anxiolytic properties are useful for the treatments of several neurological and psychiatric disorders via reducing the risks of side effects obtained with the commercial drugs. The principal disadvantages of endogenous neurosteroids administration are their rapid metabolism and their low oral bioavailability. Synthetic steroids analogues with major stability or endogenous neurosteroids stimulation synthesis might constitute promising novel strategies for the treatment of several disorders. Numerous studies indicate that the 3α-hydroxyl configuration is the key for binding and activity, but modifications in the steroid nucleus may emphasize different pharmacophores. So far, several synthetic steroids have been developed with successful neurosteroid-like effects. In this work, we summarize the properties of various synthetic steroids probed in trials throughout the analysis of several neurosteroids-like actions.

  11. Synthetic neurosteroids on brain protection

    Institute of Scientific and Technical Information of China (English)

    Mariana Rey; Hctor Coirini

    2015-01-01

    Neurosteroids, like allopregnanolone and pregnanolone, are endogenous regulators of neuronal excitability. Inside the brain, they are highly selective and potent modulators of GABAA receptor activity. Their anticonvulsant, anesthetics and anxiolytic properties are useful for the treatments of several neurological and psychiatric disordersvia reducing the risks of side effects obtained with the commercial drugs. The principal disadvantages of endogenous neurosteroids adminis-tration are their rapid metabolism and their low oral bioavailability. Synthetic steroids analogues with major stability or endogenous neurosteroids stimulation synthesis might constitute prom-ising novel strategies for the treatment of several disorders. Numerous studies indicate that the 3α-hydroxyl conifguration is the key for binding and activity, but modiifcations in the steroid nucleus may emphasize different pharmacophores. So far, several synthetic steroids have been developed with successful neurosteroid-like effects. In this work, we summarize the properties of various synthetic steroids probed in trials throughout the analysis of several neurosteroids-like actions.

  12. Microfluidic Technologies for Synthetic Biology

    Directory of Open Access Journals (Sweden)

    Sung Kuk Lee

    2011-06-01

    Full Text Available Microfluidic technologies have shown powerful abilities for reducing cost, time, and labor, and at the same time, for increasing accuracy, throughput, and performance in the analysis of biological and biochemical samples compared with the conventional, macroscale instruments. Synthetic biology is an emerging field of biology and has drawn much attraction due to its potential to create novel, functional biological parts and systems for special purposes. Since it is believed that the development of synthetic biology can be accelerated through the use of microfluidic technology, in this review work we focus our discussion on the latest microfluidic technologies that can provide unprecedented means in synthetic biology for dynamic profiling of gene expression/regulation with high resolution, highly sensitive on-chip and off-chip detection of metabolites, and whole-cell analysis.

  13. Synthetic Melanin E-Ink.

    Science.gov (United States)

    Chang, Lingqian; Chen, Feng; Zhang, Xiaokang; Kuang, Tairong; Li, Mi; Hu, Jiaming; Shi, Junfeng; Lee, Ly James; Cheng, Huanyu; Li, Yiwen

    2017-05-17

    Extensive efforts have been devoted to the development of surfactant-free electronic ink (E-ink) with excellent display resolution for high-definition resolution display. Herein, we report the use of polydopamine-based synthetic melanin, a class of functional nanoparticles with similar chemical compositions and physical properties to those of naturally occurring melanin, as a new E-ink material. It was found that such E-ink displays could achieve ultrahigh resolution (>10 000 ppi) and low power consumption (operation voltage of only 1 V) in aqueous solutions. Interestingly, simple oxidation of synthetic melanin nanoparticles enables the generation of intrinsic fluorescence, allowing further development of fluorescent E-ink displays with nanoscale resolution. We describe these bioinspired materials in an initial proof-of-concept study and propose that synthetic melanin nanoparticles will be suitable for electronic nanoinks with a potential wide range of applications in molecular patterning and fluorescence bioimaging.

  14. Designer Drugs: A Synthetic Catastrophe.

    Science.gov (United States)

    Fratantonio, James; Andrade, Lawrence; Febo, Marcelo

    Synthetic stimulants can cause hallucinations, aggressive behaviors, death and are sometimes legal. These substances are sold as plant food and bath salts that are "Not for Human Consumption", therefore skirting the 1986 Federal Analogue Act and giving a false pretense of safety. Studies have proved that these substances are toxic, have a high abuse potential, and are becoming extremely prevalent in the United States. This creates a dilemma for law enforcement agents, hospitals, and substance use disorder treatment centers. Urine Drug Testing is utilized as a clinical diagnostic tool in substance use disorder treatment centers, and the furious pace at which new synthetic stimulants are introduced to the black market are making the detection via urine increasingly difficult. This article will discuss the prevalence, pharmacology and difficulty developing laboratory assays to detect synthetic stimulants.

  15. A Research on Airborne Squint Hybrid SAR

    Institute of Scientific and Technical Information of China (English)

    BIANYong; ZHOUYinqing; LIChunsheng

    2004-01-01

    In this paper, we establish the squint mode hybrid SAR (Synthetic aperture radar) geometry. Based on the squint mode SAR geometry, the hybrid SAR signal model in squint case is derived. Based on this signal model, the hybrid SAR imaging process parameter is discussed. Aimed at the squint case, we analyze not only the relationship between the resolution and SAR system parameters, but also the relation between the time extension of the maximum azimuth signal and SAR system parameters. This research establishes the theoretical foundation for the design of squint hybrid SAR and serves as a good guide for the future work of improving the resolution of squint hybrid SAR. Based on the two-step algorithm, by considering the squint angle and cubic phase term, we are going to use the deramp SC-Chirp Scaling algorithm for squint hybrid SAR imaging. This algorithm uses the deramp method for the first step processing, and the SC-Chirp Scaling algorithm for the second step processing. The process procedure of this algorithm includes the squint angle, has the explicit physical meaning, therefore is convenient for analysis. The computer simulation result proves the validity of the analysis.

  16. Hybridized tetraquarks

    Directory of Open Access Journals (Sweden)

    A. Esposito

    2016-07-01

    Full Text Available We propose a new interpretation of the neutral and charged X,Z exotic hadron resonances. Hybridized-tetraquarks are neither purely compact tetraquark states nor bound or loosely bound molecules but rather a manifestation of the interplay between the two. While meson molecules need a negative or zero binding energy, its counterpart for h-tetraquarks is required to be positive. The formation mechanism of this new class of hadrons is inspired by that of Feshbach metastable states in atomic physics. The recent claim of an exotic resonance in the Bs0π± channel by the D0 Collaboration and the negative result presented subsequently by the LHCb Collaboration are understood in this scheme, together with a considerable portion of available data on X,Z particles. Considerations on a state with the same quantum numbers as the X(5568 are also made.

  17. Hybridized Tetraquarks

    CERN Document Server

    Esposito, A.; Polosa, A.D.

    2016-01-01

    We propose a new interpretation of the neutral and charged X, Z exotic hadron resonances. Hybridized-tetraquarks are neither purely compact tetraquark states nor bound or loosely bound molecules. The latter would require a negative or zero binding energy whose counterpart in h-tetraquarks is a positive quantity. The formation mechanism of this new class of hadrons is inspired by that of Feshbach metastable states in atomic physics. The recent claim of an exotic resonance in the Bs pi+- channel by the D0 collaboration and the negative result presented subsequently by the LHCb collaboration are understood in this scheme, together with a considerable portion of available data on X, Z particles. Considerations on a state with the same quantum numbers as the X(5568) are also made.

  18. A strategy for depositing different types of cells in three dimensions to mimic tubular structures in tissues.

    Science.gov (United States)

    Yuan, Bo; Jin, Yu; Sun, Yi; Wang, Dong; Sun, Jiashu; Wang, Zhuo; Zhang, Wei; Jiang, Xingyu

    2012-02-14

    The fabrication of tubular structures, with multiple cell types forming different layers of the tube walls, is described using a stress-induced rolling membrane (SIRM). Cell orientation inside the tubes can also be controlled by topographical contact guidance. These layered tubes precisely mimic blood vessels and many other tubular structures, suggesting that they may be of great use in tissue engineering.

  19. US Competitiveness in Synthetic Biology

    Science.gov (United States)

    2015-01-01

    Synthetic biology is an emerging technical field that aims to make biology easier to engineer; the field has applications in strategically important sectors for the US economy. While the United States currently leads in synthetic biology R&D, other nations are heavily investing in order to boost their economies, which will inevitably diminish the US leadership position. This outcome is not entirely negative—additional investments will expand markets—but it is critical that the US government take steps to remain competitive: There are applications from which the US population and economy may benefit; there are specific applications with importance for national defense; and US technical leadership will ensure that US experts have a leading role in synthetic biology governance, regulation, and oversight. Measures to increase competitiveness in S&T generally are broadly applicable for synthetic biology and should be pursued. However, the US government will also need to take action on fundamental issues that will affect the field's development, such as countering anti-GMO (genetically modified organism) sentiments and anti-GMO legislation. The United States should maintain its regulatory approach so that it is the product that is regulated, not the method used to create a product. At the same time, the United States needs to ensure that the regulatory framework is updated so that synthetic biology products do not fall into regulatory gaps. Finally, the United States needs to pay close attention to how synthetic biology applications may be governed internationally, such as through the Nagoya Protocol of the Convention on Biological Diversity, so that beneficial applications may be realized. PMID:26690379

  20. Synthetic biology as red herring.

    Science.gov (United States)

    Preston, Beth

    2013-12-01

    It has become commonplace to say that with the advent of technologies like synthetic biology the line between artifacts and living organisms, policed by metaphysicians since antiquity, is beginning to blur. But that line began to blur 10,000 years ago when plants and animals were first domesticated; and has been thoroughly blurred at least since agriculture became the dominant human subsistence pattern many millennia ago. Synthetic biology is ultimately only a late and unexceptional offshoot of this prehistoric development. From this perspective, then, synthetic biology is a red herring, distracting us from more thorough philosophical consideration of the most truly revolutionary human practice-agriculture. In the first section of this paper I will make this case with regard to ontology, arguing that synthetic biology crosses no ontological lines that were not crossed already in the Neolithic. In the second section I will construct a parallel case with regard to cognition, arguing that synthetic biology as biological engineering represents no cognitive advance over what was required for domestication and the new agricultural subsistence pattern it grounds. In the final section I will make the case with regard to human existence, arguing that synthetic biology, even if wildly successful, is not in a position to cause significant existential change in what it is to be human over and above the massive existential change caused by the transition to agriculture. I conclude that a longer historical perspective casts new light on some important issues in philosophy of technology and environmental philosophy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. US Competitiveness in Synthetic Biology.

    Science.gov (United States)

    Gronvall, Gigi Kwik

    2015-01-01

    Synthetic biology is an emerging technical field that aims to make biology easier to engineer; the field has applications in strategically important sectors for the US economy. While the United States currently leads in synthetic biology R&D, other nations are heavily investing in order to boost their economies, which will inevitably diminish the US leadership position. This outcome is not entirely negative--additional investments will expand markets--but it is critical that the US government take steps to remain competitive: There are applications from which the US population and economy may benefit; there are specific applications with importance for national defense; and US technical leadership will ensure that US experts have a leading role in synthetic biology governance, regulation, and oversight. Measures to increase competitiveness in S&T generally are broadly applicable for synthetic biology and should be pursued. However, the US government will also need to take action on fundamental issues that will affect the field's development, such as countering anti-GMO (genetically modified organism) sentiments and anti-GMO legislation. The United States should maintain its regulatory approach so that it is the product that is regulated, not the method used to create a product. At the same time, the United States needs to ensure that the regulatory framework is updated so that synthetic biology products do not fall into regulatory gaps. Finally, the United States needs to pay close attention to how synthetic biology applications may be governed internationally, such as through the Nagoya Protocol of the Convention on Biological Diversity, so that beneficial applications may be realized.

  2. Smart self-assembled hybrid hydrogel biomaterials.

    Science.gov (United States)

    Kopeček, Jindřich; Yang, Jiyuan

    2012-07-23

    Hybrid biomaterials are systems created from components of at least two distinct classes of molecules, for example, synthetic macromolecules and proteins or peptide domains. The synergistic combination of two types of structures may produce new materials that possess unprecedented levels of structural organization and novel properties. This Review focuses on biorecognition-driven self-assembly of hybrid macromolecules into functional hydrogel biomaterials. First, basic rules that govern the secondary structure of peptides are discussed, and then approaches to the specific design of hybrid systems with tailor-made properties are evaluated, followed by a discussion on the similarity of design principles of biomaterials and macromolecular therapeutics. Finally, the future of the field is briefly outlined.

  3. Comparative analysis of the outdoor culture of Haematococcus pluvialis in tubular and bubble column photobioreactors.

    Science.gov (United States)

    López, M C García-Malea; Sánchez, E Del Río; López, J L Casas; Fernández, F G Acién; Sevilla, J M Fernández; Rivas, J; Guerrero, M G; Grima, E Molina

    2006-05-29

    The present paper makes a comparative analysis of the outdoor culture of H. pluvialis in a tubular photobioreactor and a bubble column. Both reactors had the same volume and were operated in the same way, thus allowing the influence of the reactor design to be analyzed. Due to the large changes in cell morphology and biochemical composition of H. pluvialis during outdoor culture, a new, faster methodology has been developed for their evaluation. Characterisation of the cultures is carried out on a macroscopic scale using a colorimetric method that allows the simultaneous determination of biomass concentration, and the chlorophyll, carotenoid and astaxanthin content of the biomass. On the microscopic scale, a method was developed based on the computer analysis of digital microscopic images. This method allows the quantification of cell population, average cell size and population homogeneity. The accuracy of the methods was verified during the operation of outdoor photobioreactors on a pilot plant scale. Data from the reactors showed tubular reactors to be more suitable for the production of H. pluvialis biomass and/or astaxanthin, due to their higher light availability. In the tubular photobioreactor biomass concentrations of 7.0 g/L (d.wt.) were reached after 16 days, with an overall biomass productivity of 0.41 g/L day. In the bubble column photobioreactor, on the other hand, the maximum biomass concentration reached was 1.4 g/L, with an overall biomass productivity of 0.06 g/L day. The maximum daily biomass productivity, 0.55 g/L day, was reached in the tubular photobioreactor for an average irradiance inside the culture of 130 microE/m2s. In addition, the carotenoid content of biomass from tubular photobioreactor increased up to 2.0%d.wt., whereas that of the biomass from the bubble column remained roughly constant at values of 0.5%d.wt. It should be noted that in the tubular photobioreactor under conditions of nitrate saturation, there was an accumulation of

  4. Sequential Beamforming Synthetic Aperture Imaging

    DEFF Research Database (Denmark)

    Kortbek, Jacob; Jensen, Jørgen Arendt; Gammelmark, Kim Løkke

    2013-01-01

    Synthetic aperture sequential beamforming (SASB) is a novel technique which allows to implement synthetic aperture beamforming on a system with a restricted complexity, and without storing RF-data. The objective is to improve lateral resolution and obtain a more depth independent resolution...... and a range independent lateral resolution is obtained. The SASB method has been investigated using simulations in Field II and by off-line processing of data acquired with a commercial scanner. The lateral resolution increases with a decreasing F#. Grating lobes appear if F# 6 2 for a linear array with k-pitch...

  5. Design Automation in Synthetic Biology.

    Science.gov (United States)

    Appleton, Evan; Madsen, Curtis; Roehner, Nicholas; Densmore, Douglas

    2017-04-03

    Design automation refers to a category of software tools for designing systems that work together in a workflow for designing, building, testing, and analyzing systems with a target behavior. In synthetic biology, these tools are called bio-design automation (BDA) tools. In this review, we discuss the BDA tools areas-specify, design, build, test, and learn-and introduce the existing software tools designed to solve problems in these areas. We then detail the functionality of some of these tools and show how they can be used together to create the desired behavior of two types of modern synthetic genetic regulatory networks.

  6. Synthetic Phage for Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    So Young Yoo

    2014-01-01

    Full Text Available Controlling structural organization and signaling motif display is of great importance to design the functional tissue regenerating materials. Synthetic phage, genetically engineered M13 bacteriophage has been recently introduced as novel tissue regeneration materials to display a high density of cell-signaling peptides on their major coat proteins for tissue regeneration purposes. Structural advantages of their long-rod shape and monodispersity can be taken together to construct nanofibrous scaffolds which support cell proliferation and differentiation as well as direct orientation of their growth in two or three dimensions. This review demonstrated how functional synthetic phage is designed and subsequently utilized for tissue regeneration that offers potential cell therapy.

  7. Synthetic biology and its promises

    Directory of Open Access Journals (Sweden)

    José Manuel De Cózar Escalante

    2016-12-01

    Full Text Available Synthetic biology is a new science and emerging technology, or rather a technoscience, which converges with others such as nanotechnology, information technology, robotics, artificial intelligence and neuroscience. All have common features that could have highly concerning social and environmental impacts. With its ambitious goals of controlling complexity, redesigning and creating new living entities, synthetic biology perfectly exemplifies the new bioeconomic reality. This requires expanding the focus of the discussion beyond the limited comparative analysis of risks and benefits, to address uncertainties, reassign responsibilities and initiate a thorough social assessment of what is at stake.

  8. Composite Epstein-Barr Virus-Associated B-Cell Lymphoproliferative Disorder and Tubular Adenoma in a Rectal Polyp.

    Science.gov (United States)

    Lo, Amy A; Gao, Juehua; Rao, M Sambasivia; Yang, Guang-Yu

    2016-02-01

    Composite tumors are formed when there is intermingling between two components of separate tumors seen histologically. Cases demonstrating composite tubular adenoma with other types of tumors in the colon are rare. Composite tubular adenomas with nonlymphoid tumors including carcinoids, microcarcinoids, and small cell undifferentiated carcinoma have been reported in the literature. The occurrence of composite lymphoma and tubular adenoma within the colorectal tract is extremely rare. Only three cases have been reported and include one case of mantle cell lymphoma and two cases of diffuse large B-cell lymphoma arising in composite tubular adenomas. We present the first case of composite Epstein-Barr virus-associated B-cell lymphoproliferative disorder and tubular adenoma in a rectal polyp with a benign endoscopic appearance.

  9. Insulin's acute effects on glomerular filtration rate correlate with insulin sensitivity whereas insulin's acute effects on proximal tubular sodium reabsorption correlate with salt sensitivity in normal subjects

    NARCIS (Netherlands)

    ter Maaten, JC; Bakker, SJL; Serne, EH; ter Wee, PM; Gans, ROB

    1999-01-01

    Background. Insulin induces increasing distal tubular sodium reabsorption. Opposite effects of insulin to offset insulin-induced sodium retention are supposedly increases in glomerular filtration rate (GFR) and decreases in proximal tubular sodium reabsorption. Defects in these opposing effects coul

  10. Insulin's acute effects on glomerular filtration rate correlate with insulin sensitivity whereas insulin's acute effects on proximal tubular sodium reabsorption correlate with salt sensitivity in normal subjects

    NARCIS (Netherlands)

    ter Maaten, JC; Bakker, SJL; Serne, EH; ter Wee, PM; Gans, ROB

    1999-01-01

    Background. Insulin induces increasing distal tubular sodium reabsorption. Opposite effects of insulin to offset insulin-induced sodium retention are supposedly increases in glomerular filtration rate (GFR) and decreases in proximal tubular sodium reabsorption. Defects in these opposing effects coul

  11. Electrochemical Detection of a Dengue-related Oligonucleotide Sequence Using Ferrocenium as a Hybridization Indicator

    OpenAIRE

    José Luiz de Lima-Filho; Duarte Miguel França dos Prazeres; ernando Rodrigues Ribeiro Teles

    2007-01-01

    A simple method for electrochemical detection of a synthetic 20-bp oligonucleotide sequence related with dengue virus genome was developed. A complimentary DNA probe sequence was electrostatically immobilized onto a glassy carbon electrode modified with chitosan. Electrochemical detection of hybridization between probe and target was performed by cyclic voltammetry, using ferrocene (Fc+) as a hybridization label. After hybridization, the peak current response of Fc+ oxidation increased around...

  12. Evaluation of hybrid composite materials in cylindrical specimen geometries

    Science.gov (United States)

    Liber, T.; Daniel, I. M.

    1976-01-01

    Static and fatigue properties of three composite materials and hybrids were examined. The materials investigated were graphite/epoxy, S-glass/epoxy, PRD-49 (Kevlar 49)/epoxy, and hybrids in angle-ply configurations. A new type of edgeless cylindrical specimen was developed. It is a flattened tube with two flat sides connected by curved sections and it is handled much like the standard flat coupon. Special specimen fabrication, tabbing, and tab region reinforcing techniques were developed. Axial modulus, Poisson's ratio, strength, and ultimate strain were obtained under static loading from flattened tube specimens of nine laminate configurations. In the case of graphite/epoxy the tubular specimens appeared to yield somewhat higher strength and ultimate strain values than flat specimens. Tensile fatigue tests were conducted with all nine types of specimens and S-N curves obtained. Specimens surviving 10 million cycles of tensile loading were subsequently tested statically to failure to determine residual properties.

  13. Suspended hybrid films assembled from thiol-capped gold nanoparticles.

    Science.gov (United States)

    Zhang, Yu Xin; Huang, Ming; Hao, Xiao Dong; Dong, Meng; Li, Xin Lu; Huang, Jia Mu

    2012-01-01

    In this work, we explored the formation processes of suspended hybrid thin films of thiol-capped Au nanoparticles (AuNPs) inside metal oxide tubular structures. We found that a balance between in-film interactions of the AuNPs and boundary interactions with metal oxides is a key in making these special organic-inorganic thin films. The hybrid films process many processing advantages and flexibilities, such as controllable film thickness, interfacial shape and inter-AuNPs distance, tuning of particle sizes, thiol population, chain lengths, and other new properties by introducing functional groups to thiol chains. Among their many unique features, the assembly-disassembly property may be useful for future on-off or store-release applications.

  14. MATHEMATICAL MODELLING OF PREFERED SOLUTIONS CHOICE FUNCTION FOR TUBULAR GAS HEATERS BY EXPERIMENTAL INFORMATIONS

    Directory of Open Access Journals (Sweden)

    BARSUK R. V.

    2016-08-01

    Full Text Available Annotation. Problems formulation. The article deals with choice functions building of preferred solutions by experimental information for tubular gas heater working on fuel granules - pellets.Further choice functions using for making technical solutions by tubular gas heaters construction and designing. Recently research analysis. There are works about choice functions construction by separate presents are examined. But full chose functions building by separate presents are not examined. Aims and tasks. There are setting aim to develop full choice functions mathematical model on separate presents by authors. The expert are connect to primary experimental data’s evaluation that estimates separate results by output functions (criteria. Its evaluations issue in experimental points paired comparison’s table form. Thus, there are necessary construct binary choice relations presents on experimental “points” set by expert that then using for full choice function’s constructing. Conclusions. There are choice function’s construction’s sequence are sets. There are posed point comparison results that characterized tubular gas heater’s condition with expert’s evaluation using. Also posed output functions comparisons by which can be characterized improving tubular gas heater’s performance or vice versa.

  15. Micro-tubular solid oxide fuel cell based on a porous yttria-stabilized zirconia support.

    Science.gov (United States)

    Panthi, Dhruba; Tsutsumi, Atsushi

    2014-08-29

    Solid oxide fuel cells (SOFCs) are promising electrochemical energy conversion devices owing to their high power generation efficiency and environmentally benign operation. Micro-tubular SOFCs, which have diameters ranging from a few millimeters to the sub-millimeter scale, offer several advantages over competing SOFCs such as high volumetric power density, good endurance against thermal cycling, and flexible sealing between fuel and oxidant streams. Herein, we successfully realized a novel micro-tubular SOFC design based on a porous yttria-stabilized zirconia (YSZ) support using multi-step dip coating and co-sintering methods. The micro-tubular SOFC consisted of Ni-YSZ, YSZ, and strontium-doped lanthanum manganite (LSM)-YSZ as the anode, electrolyte, and cathode, respectively. In addition, to facilitate current collection from the anode and cathode, Ni and LSM were applied as an anode current collector and cathode current collector, respectively. Micro-crystalline cellulose was selected as a pore former to achieve better shrinkage behavior of the YSZ support so that the electrolyte layer could be densified at a co-sintering temperature of 1300 °C. The developed micro-tubular design showed a promising electrochemical performance with maximum power densities of 525, 442, and 354 mW cm(-2) at 850, 800, and 750 °C, respectively.

  16. CFD simulation for reduced energy costs in tubular photobioreactors using wall turbulence promoters

    NARCIS (Netherlands)

    Gomez Perez, Cesar; Espinosa, J.; Montenegro Ruiz, L.C.; Boxtel, van A.J.B.

    2015-01-01

    Tubular photobioreactors (PBR) have great potential for microalgae cultivation due to its high productivity compared with open ponds. However, the energy uptake for fluid circulation and mixing is significant, impacting the operation and production costs. In this work, we investigate by CFD simulati

  17. [Lumen morphogenesis and molecular mechanisms in tubular organs during zebrafish embryonic development].

    Science.gov (United States)

    Xiao, Chun; Hu, Huo-Zhen; Mo, Xian-Ming

    2013-04-01

    A network tubular system is an important structure in the body and organ of metazoa. The lumen of tube is fundamental units in the structure, which serve to transport material, divide the organ into different functional compartments and separate the organ from the environment. The defects of lumen formation will lead to abnormalities of the organ morphogenesis and disorder of the function. Zebrafish (Danio rerio)is an important model for development research. Meanwhile easy observation of tubular organ, the relevant mutants, and transgene linages make zebrafish to become an excellent model to study the formation of lumen in the tubular organs, including the blood vessels, neural tube, gut, exocrine pancreas, and pronephric duct, which undergo the typical morphogenesis of lumen that is involved in the organs' development. The process of lumen formation is mainly consisted of induction of extracellular signals, polarization of epithelial cell, directional transportation in the polar cells, the aggregation and transportation of fluid in the lumen, and the reconstruction of cytoskeleton in polar cells and controlled by the precise and complicated molecular networks during embryonic development. This review will summarize our current knowledge on lumen morphogenesis in four kinds of typical tubular organs during zebrafish embryonic development and the related molecular mechanisms as well as to supply helpful reference to the future studies.

  18. Biotransformation, transport and toxicity studies in rat renal proximal tubular cells.

    NARCIS (Netherlands)

    Haenen, H.E.M.G.

    1996-01-01

    SummaryRenal proximal tubular (RPT) cells can be exposed apically to glomerulary filtrated and basolaterally to non-filtrated nephrotoxic compounds. To excrete these compounds via the urine, RPT cells are equipped with transport systems able to transport nephrotoxicants from the basolateral to the a

  19. Gender Difference of Cadmium-induced Renal Tubular Dysfunction for Inhabitants in Toyama,Japan

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective The aim of the present study was to compare the gender differencefor cadmium-induced renal tubular dysfunction between the male and female inhabitants. MethodsUrinary β2-microglobulin was measured in 299 male (94%) and 342 female (92%) inhabitants aged54 - 72 years,and the development of renal tubular dysfunction for 11 years was studied in the 62married couples from them. Results A significantly higher cumulative incidence was found in bothmen and women in cudmium-polluted area,showing 68. 4% in men and 64.8% in women compared to15.3 % in men and 5.9 % in women in the reference areas. Relative risk of renal tubular dysfunctionin females (11.0) was higher than males (4.5). The ratios of urinary β2-nicroglobulin and glucosewere higher in women than those in men in both the cadmium-polluted areas and the reference areas.Conclusion Although almost identical incidences were detected between men and wonen, the changesin excretion of β2-microglobulin and glucose was greater in women than those in men. These findings sug-gest that renal tubular dysfunction might be more progressive in women than that in men.

  20. Photonic band gaps in materials with triply periodic surfaces and related tubular structures

    NARCIS (Netherlands)

    Michielsen, K; Kole, JS

    2003-01-01

    We calculate the photonic band gap of triply periodic bicontinuous cubic structures and of tubular structures constructed from the skeletal graphs of triply periodic minimal surfaces. The effect of the symmetry and topology of the periodic dielectric structures on the existence and the characteristi