WorldWideScience

Sample records for biomolecules perspectivas diagnosticas

  1. Diagnostic and therapeutic perspectives in nuclear medicine: radiolabelled biomolecules; Perspectivas diagnosticas y terapeuticas en medicina nuclear: biomoleculas radiomarcadas

    Energy Technology Data Exchange (ETDEWEB)

    Ferro F, G. [Gerencia de Aplicaciones Nucleares en la Salud. ININ, 11801 Mexico D.F. (Mexico); Murphy, C.A. de; Pedraza L, M. [Departamento de Medicina Nuclear. Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico D.F. (Mexico); Melendez A, L. [Facultad de Medicina, UAEM, 50000 Toluca, Estado de Mexico (Mexico)

    2003-07-01

    From their beginning, the radiopharmaceuticals chemistry has gone to the study of the molecular chemistry. The radiopharmaceuticals are only in their capacity to detect such specific biochemical places as the receivers and the enzymes. With the recent obtaining of the complete structural sequence of the genome, it doesn't fit doubt of the importance that they have acquired the molecular images for the study from the genetic information to the alterations phenotypic in the chemistry of the human body. So, the future of the diagnostic and therapeutic nuclear medicine, practically is based in the study of protein fragments, peptide structures and chains of DNA radiolabelled for the study of the metabolism In vivo. These investigations represent a substantial change in those paradigms of the pharmaceutical development, when using the own organic capacities as source of medications, instead of considering to the organism like a simple assay tube where molecules act, like they are most of the traditional medications. The investigation of new techniques to design complex stable of Tc-99m, Re-188, Lu-177, Y-90 and Dy-166/Ho-l66 with biomolecules that don't alter the specificity and in general the molecular properties of the same ones. it is a topic of world interest in the environment of the radiopharmaceutical chemistry. In this work some achievements and perspectives are presented on those main diagnostic and therapeutic radiopharmaceuticals of third generation. (Author)

  2. La diagnostica ecografica nello studio della displasia dell'anca del cane

    OpenAIRE

    Manfredi, Sabrina

    2012-01-01

    L’ultrasonografia è una metodica di diagnostica per immagini routinariamente utilizzata sia in medicina umana che in medicina veterinaria. Da numerosi anni le applicazioni sono innumerevoli sia in campo umano che veterinario e, in particolare nell’imaging muscolo-scheletrico, rappresenta la tecnica che si sta sviluppando più rapidamente. In medicina umana, la displasia congenita dell’anca compare in un modesto ma significativo numero di bambini, e l’intervallo di tempo per trattare la pato...

  3. Biomolecules in Astrobiology

    OpenAIRE

    Meringer, Markus

    2013-01-01

    Astrobiology is the study of the origin, distribution and future of life in the universe, biomolecules are molecules produced by living organisms. This talk reviews known facts and open questions about biomolecules in the context of Astrobiology and introduces a research project on "Creating a Reference Set of Amino Acids Structures for Use in Multiple Astrobiology Investigations" that tries to find answers using computational methods.

  4. Nonlinear excitations in biomolecules

    International Nuclear Information System (INIS)

    The aim of the workshop entitled ''Nonlinear Excitations in Biomolecules'' is to attempt to bridge the gap between the physicists and biologists communities which is mainly due to language and cultural barriers. The progress of nonlinear science in the last few decades which have shown that the combination of nonlinearity, which characterize most biological phenomena, and cooperative effects in a system having a large number of degrees of freedom, can give rise to coherent excitations with remarkable properties. New concepts, such as solitons nd nonlinear energy localisation have become familiar to physicists and applied mathematicians. It is thus tempting to make an analogy between these coherent excitations and the exceptional stability of some biological processes, such as for instance DNA transcription, which require the coordination of many events in the ever changing environment of a cell. Physicists are now invoking nonlinear excitations to describe and explain many bio-molecular processes while biologists often doubt that the seemingly infinite variety of phenomena that they are attempting to classify can be reduced to such simple concepts. A large part of the meeting is devoted to tutorial lectures rather than to latest research results. The book provides a pedagogical introduction to the two topics forming the backbone of the meeting: the theory of nonlinear excitations and solitons, and their application in biology; and the structure and function of biomolecules, as well as energy and charge transport in biophysics. In order to emphasize the link between physics and biology, the volume is not divided along these two topics but according to biological subjects. Each chapter starts with a short introduction attempting to help the reader to find his way among the contributions and point out the connection between them. 23 lectures over the 32 presented have been selected and refers to quantum properties of macro-molecules. (J.S.)

  5. Biomolecule labelling by 186 Re

    International Nuclear Information System (INIS)

    The aim of this study is to develop and improve the existing radiolabelling techniques of peptides and monoclonal antibodies with 186 Re and 188 Re as potential agents for cancer targeted radiotherapy. We selected the following methods and techniques for direct labelling of peptides and monoclonal antibody: 1. Prereduction of -S-S- bridges of biomolecule to sulfhydryls using reducing agents: ascorbic acid, cysteine, active hydrogen, 2,3 dimercaptopropanol. The prereduction reactions are controlled by massic ratios of reduction agents/biomolecule, pH, temperature and time of incubation; 2. Reduction of 186 Re O4- stannous chloride in acid and alkaline pH; 3. Coupling reaction of 186 Re (red) with the biomolecule controlled by the time and temperature of incubation, the influence of pH regarding the binding of 186 Re to the biomolecules. The quality control was effected by chromatography techniques (paper and elution gel chromatography) on labeled biomolecule before and after purification. The elution gel chromatography was spectrophotometricaly monitored at 280 nm. In the same time the radioactivity of samples was measured using a gamma counter. All the results confirm in vitro stability of labeled biomolecule. The biological evaluation studies regarding accumulation and biological affinity will be controlled by scintigraphy method. Biodistribution studies will be effected to Walker tumor bearing animals at 4 and 24 hours after injections. (authors)

  6. Simulating biomolecules in cellular environments

    Czech Academy of Sciences Publication Activity Database

    Feig, M.; Tanizaki, S.; Chocholoušová, Jana; Sayadi, M.; Clifford, J. W.; Connelly, B. D.; Mukherjee, S.; Law, S. M.

    Jüllich : John von Neumann Institute for Computing, 2008 - (Hansmann, U.; Meinke, J.; Mohanty, S.), s. 23-30 ISBN 978-3-9810843-6-8. - ( NIC Series. 40). [From Computational Biophysics to Systems Biology (CBSB08). NIC Workshop 2008. Jülich (US), 19.05.2008-21.05.2008] Institutional research plan: CEZ:AV0Z40550506 Keywords : generalized Born formalism * implicit solvent * biomolecules Subject RIV: CC - Organic Chemistry http://www.fz-juelich.de/ nic -series/volume40

  7. BSDB: the biomolecule stretching database

    OpenAIRE

    Sikora, Mateusz; Sułkowska, Joanna I.; Bartłomiej S. Witkowski; Cieplak, Marek

    2010-01-01

    We describe the Biomolecule Stretching Data Base that has been recently set up at http://www.ifpan.edu.pl/BSDB/. It provides information about mechanostability of proteins. Its core is based on simulations of stretching of 17 134 proteins within a structure-based model. The primary information is about the heights of the maximal force peaks, the force–displacement patterns, and the sequencing of the contact-rupturing events. We also summarize the possible types of the mechanical clamps, i.e. ...

  8. BSDB: the Biomolecule Stretching Database

    Science.gov (United States)

    Cieplak, Marek; Sikora, Mateusz; Sulkowska, Joanna I.; Witkowski, Bartlomiej

    2011-03-01

    Despite more than a decade of experiments on single biomolecule manipulation, mechanical properties of only several scores of proteins have been measured. A characteristic scale of the force of resistance to stretching, Fmax , has been found to range between ~ 10 and 480 pN. The Biomolecule Stretching Data Base (BSDB) described here provides information about expected values of Fmax for, currently, 17 134 proteins. The values and other characteristics of the unfolding proces, including the nature of identified mechanical clamps, are available at www://info.ifpan.edu.pl/BSDB/. They have been obtained through simulations within a structure-based model which correlates satisfactorily with the available experimental data on stretching. BSDB also lists experimental data and results of the existing all-atom simulations. The database offers a Protein-Data-Bank-wide guide to mechano-stability of proteins. Its description is provided by a forthcoming Nucleic Acids Research paper. Supported by EC FUNMOL project FP7-NMP-2007-SMALL-1, and European Regional Development Fund: Innovative Economy (POIG.01.01.02-00-008/08).

  9. EVALUACIÓN DE LOS PROTOCOLOS IPSEC Y SSL EN LA TRANSMISIÓN SEGURA DE IMÁGENES DIAGNOSTICAS EN TELERADIOLOGIA UTILIZANDO EL ESTÁNDAR DICOM

    OpenAIRE

    Jorge Luis Lugo Rosero; Oscar Andrés Pérez Acuña; Nancy Y. García

    2011-01-01

    Las imágenes diagnosticas digitales constituyen hoy día un paradigma de requerimientos para cualquier sistema informático; se debe garantizar la confidencialidad de la información médica de los pacientes mediante sistemas de comunicación seguros, cumpliendo de esta manera con las políticas de control de calidad en técnicas de Teleradiologia. En este articulo primero se describe un escenario típico de comunicación entre los dispositivos de captura de placas y los elementos de visualizacion y a...

  10. EVALUACIÓN DE LOS PROTOCOLOS IPSEC Y SSL EN LA TRANSMISIÓN SEGURA DE IMÁGENES DIAGNOSTICAS EN TELERADIOLOGIA UTILIZANDO EL ESTÁNDAR DICOM

    Directory of Open Access Journals (Sweden)

    Jorge Luis Lugo Rosero

    2011-08-01

    Full Text Available Las imágenes diagnosticas digitales constituyen hoy día un paradigma de requerimientos para cualquier sistema informático; se debe garantizar la confidencialidad de la información médica de los pacientes mediante sistemas de comunicación seguros, cumpliendo de esta manera con las políticas de control de calidad en técnicas de Teleradiologia. En este articulo primero se describe un escenario típico de comunicación entre los dispositivos de captura de placas y los elementos de visualizacion y almacenamiento de las mismas, asi como la forma en la que se transmiten dichas tomas diagnosticas de un sitio a otro, posteriormente se realiza la comparación entre  los protocolos más utilizados en esta tarea y finalmente se analizan los resultados obtenidos al transmitir varios estudios medicos por una red LAN garantizando la seguridad y confidencialidad de los datos de trabajo.

  11. Magnetic GMI sensor for detection of biomolecules

    International Nuclear Information System (INIS)

    A magnetic sensor based on the giant magnetoimpedance (GMI) effect for the detection of biomolecules was made with a CoFeSiB amorphous magnetic microwire as sensing element. Using soft ferromagnetic cobalt microparticles and field sensitivities of the impedance of about 2.5%/A m-1 in the very low field region (less than 200 A m-1) at frequencies close to 10 MHz, a highly sensitive response was measured, appropriate for the detection of low biomolecule concentrations

  12. Ampliando as perspectivas

    OpenAIRE

    Ângela Tonietto; Bruno Telles; Charles Albert Andrade; Claudemir Rodrigues Dias Filho; Juliano de Andrade Gomes

    2015-01-01

    Escrever um editorial de uma revista científica não é uma tarefa fácil. É como introduzir um estranho num ninho dominado por linguagens técnicas e experimentos. Parece que estamos quebrando uma regra ou fazendo algo de errado. Contudo, esse é o caminho que a equipe editorial tem para se comunicar com a comunidade de pesquisadores forenses, expor nossas perspectivas e impulsionar as novas submissões.

  13. Nietzsche en perspectiva

    OpenAIRE

    Berten, André; Borradori, Giovanna; Brusotti, Marco; Cifuentes, Luis Antonio; Cragnolini, Mónica; Fogel, Gilvan; Hanza, Kathia; Jara, José; Mainberger, Sabine; Meléndez, Germán; Tugendhat, Ernst; Vásquez, Carlos; Winchester, James

    2001-01-01

    En este texto se reúne un conjunto de ensayos recientes e inéditos casi todos, de reconocidos estudiosos de la obra de Friedrich Nietzsche (1844-1900), que fueron presentados con motivo de la celebración del primer centenario de la muerte de este gran filósofo alemán durante el Encuentro Internacional: Nietzche en perspectiva. / Contenido. Preliminares; Capítulo 1 - A manera de introducción: el amor por el saber en Nietzsche; Capítulo 2 - Subjetividad y ontología de la fuerza; Capítulo 3 - Cu...

  14. Microorganisms and biomolecules in space hard environment

    Science.gov (United States)

    Horneck, G.

    1981-01-01

    Microorganisms and biomolecules exposed to space vacuum and to different intensities of selected wavelengths of solar ultraviolet radiation is studied. The influence of these factors, applied singly or simultaneously, on the integrity of microbial systems and biomolecules is measured. Specifically, this experiment will study in Bacillus subtilis spores (1) disturbances in subsequent germination, outgrowth, and colony formation; (2) photochemical reactions of the DNA and protein in vivo and in vitro and their role in biological injury; and (3) the efficiency of repair processes in these events.

  15. Tuneable graphene nanopores for single biomolecule detection.

    Science.gov (United States)

    Al-Dirini, Feras; Mohammed, Mahmood A; Hossain, Md Sharafat; Hossain, Faruque M; Nirmalathas, Ampalavanapillai; Skafidas, Efstratios

    2016-05-21

    Solid-state nanopores are promising candidates for next generation DNA and protein sequencing. However, once fabricated, such devices lack tuneability, which greatly restricts their biosensing capabilities. Here we propose a new class of solid-state graphene-based nanopore devices that exhibit a unique capability of self-tuneability, which is used to control their conductance, tuning it to levels comparable to the changes caused by the translocation of a single biomolecule, and hence, enabling high detection sensitivities. Our presented quantum simulation results suggest that the smallest amino acid, glycine, when present in water and in an aqueous saline solution can be detected with high sensitivity, up to a 90% change in conductance. Our results also suggest that passivating the device with nitrogen, making it an n-type device, greatly enhances its sensitivity, and makes it highly sensitive to not only the translocation of a single biomolecule, but more interestingly to intramolecular electrostatics within the biomolecule. Sensitive detection of the carboxyl group within the glycine molecule, which carries a charge equivalent to a single electron, is achieved with a conductance change that reaches as high as 99% when present in an aqueous saline solution. The presented findings suggest that tuneable graphene nanopores, with their capability of probing intramolecular electrostatics, could pave the way towards a new generation of single biomolecule detection devices. PMID:27171594

  16. Tuneable graphene nanopores for single biomolecule detection

    Science.gov (United States)

    Al-Dirini, Feras; Mohammed, Mahmood A.; Hossain, Md Sharafat; Hossain, Faruque M.; Nirmalathas, Ampalavanapillai; Skafidas, Efstratios

    2016-05-01

    Solid-state nanopores are promising candidates for next generation DNA and protein sequencing. However, once fabricated, such devices lack tuneability, which greatly restricts their biosensing capabilities. Here we propose a new class of solid-state graphene-based nanopore devices that exhibit a unique capability of self-tuneability, which is used to control their conductance, tuning it to levels comparable to the changes caused by the translocation of a single biomolecule, and hence, enabling high detection sensitivities. Our presented quantum simulation results suggest that the smallest amino acid, glycine, when present in water and in an aqueous saline solution can be detected with high sensitivity, up to a 90% change in conductance. Our results also suggest that passivating the device with nitrogen, making it an n-type device, greatly enhances its sensitivity, and makes it highly sensitive to not only the translocation of a single biomolecule, but more interestingly to intramolecular electrostatics within the biomolecule. Sensitive detection of the carboxyl group within the glycine molecule, which carries a charge equivalent to a single electron, is achieved with a conductance change that reaches as high as 99% when present in an aqueous saline solution. The presented findings suggest that tuneable graphene nanopores, with their capability of probing intramolecular electrostatics, could pave the way towards a new generation of single biomolecule detection devices.

  17. Immobilizing Biomolecules Near the Diffraction Limit

    DEFF Research Database (Denmark)

    Skovsen, Esben; Petersen, Maria Teresa Neves; Gennaro, Ane Kold Di;

    2009-01-01

    Our group has previously shown that biomolecules containing disulfide bridges in close proximity to aromatic residues can be immobilized, through covalent bonds, onto thiol derivatized surfaces upon UV excitation of the aromatic residue(s). We have also previously shown that our new technology ca...

  18. PREFACE: Structure and Function of Biomolecules

    Science.gov (United States)

    Cieplak, Marek; Sienkiewicz, Andrzej

    2005-05-01

    The Workshop on the Structure and Function of Biomolecules took place in Bedlewo near Poznan, Poland, on 13-15 May 2004, two weeks after Poland joined the European Community. The Workshop was sponsored by the ASPECT Centre of Excellence for Advanced Spectroscopy Applications in Physics, Modern Science, Biology and Environmental Protection (the European Community contract GMA1-2002-72801) and by the Institute of Physics, Polish Academy of Sciences. The Workshop gathered together approximately 100 participants mostly from the European Community but also from Canada, Russia, Switzerland, Turkey and the USA. The scientific aim of this Workshop was to provide an active forum for cross-disciplinary interactions between specialists who are active in different fields related to biomolecules, with an emphasis on proteins and nucleic acids. The workshop covered both experimental and theoretical issues. The subjects that were discussed included: mechanical stretching of biomolecules, protein kinetics and structure, aggregation of biomolecules, and novel spectroscopic methods for studying protein conformation. There were 36 invited lectures and 33 poster contributions presented at the Workshop. This Special Issue of Journal of Physics: Condensed Matter contains a sample of the research presented at the Workshop.

  19. A Multidisciplinary, Open Access Platform for Research on Biomolecules

    Directory of Open Access Journals (Sweden)

    Jürg Bähler

    2011-08-01

    Full Text Available I am pleased to introduce Biomolecules, a new journal to report on all aspects of science that focuses on biologically derived substances, from small molecules to complex polymers. Some examples are lipids, carbohydrates, vitamins, hormones, amino acids, nucleotides, peptides, RNA and polysaccharides, but this list is far from exhaustive. Research on biomolecules encompasses multiple fascinating questions. How are biomolecules synthesized and modified? What are their structures and interactions with other biomolecules? How do biomolecules function in biological processes, at the level of organelles, cells, organs, organisms, or even ecosystems? How do biomolecules affect either the organism that produces them or other organisms of the same or different species? How are biomolecules shaped by evolution, and how in turn do they affect cellular phenotypes? What is the systems-level contribution of biomolecules to biological function?

  20. Ionic strength independence of charge distributions in solvation of biomolecules

    OpenAIRE

    Virtanen, J. J.; Sosnick, T. R.; Freed, K. F.

    2014-01-01

    Electrostatic forces enormously impact the structure, interactions, and function of biomolecules. We perform all-atom molecular dynamics simulations for 5 proteins and 5 RNAs to determine the dependence on ionic strength of the ion and water charge distributions surrounding the biomolecules, as well as the contributions of ions to the electrostatic free energy of interaction between the biomolecule and the surrounding salt solution (for a total of 40 different biomolecule/solvent combinations...

  1. Natural Antioxidants: Fascinating or Mythical Biomolecules?

    Directory of Open Access Journals (Sweden)

    Johannes Van Staden

    2010-10-01

    Full Text Available Research on the use, properties, characteristics and sources of antioxidants especially phenolic compounds, flavonoids, vitamins, synthetic chemicals and some micronutrients began in the late 18th century. Since then antioxidant research has received considerable attention and over a hundred thousand papers have been published on the subject. This has led to a rampant use of antioxidants in order to try to obtain and preserve optimal health. A number of nutraceuticals and food supplements are frequently fortified with synthetic or natural antioxidants. However, some research outcomes have led to the belief that antioxidants exist as mythical biomolecules. This review provides a critical evaluation of some common in vitro antioxidant capacity methods, and a discussion on the role and controversies surrounding non-enzymatic biomolecules, in particular phenolic compounds and non-phenolic compounds, in oxidative processes in an attempt of stemming the tidal wave that is threatening to swamp the concept of natural antioxidants.

  2. Quantum dots and their interaction with biomolecules

    OpenAIRE

    Stanisavljević, Maja

    2015-01-01

    In this study CdTe QDs were synthetized via microwave irradiation method. Further they have been modified for purposes of their interaction with biomolecules using different conjugation approaches. Applied conjugation chemistries were non-specific interaction, streptavidin-biotin affinity. Glutathione modified CdTe QDs of 2 nm size were capable of non-specific interaction with major groove of DNA, while streptavidin modified CdTe QDs served as specific linker for biotinylated oligonucleotides...

  3. Immobilizing Biomolecules Near the Diffraction Limit

    DEFF Research Database (Denmark)

    Skovsen, Esben; Neves-Petersen, Maria Teresa; Kold, Ane;

    2009-01-01

    Our group has previously shown that biomolecules containing disulfide bridges in close proximity to aromatic residues can be immobilized, through covalent bonds, onto thiol derivatized surfaces upon UV excitation of the aromatic residue(s). We have also previously shown that our new technology ca...... a substrate, which can be generated by a UV diffraction pattern. Such patterns can have sub-micron feature sizes and could therefore be of great relevance for present and future nanotechnological applications....

  4. Separation of biomolecules using supercritical fluid extraction.

    Science.gov (United States)

    Lucien, F P; Liong, K K; Cotton, N J; Macnaughton, S J; Foster, N R

    1993-01-01

    Supercritical fluids are increasingly being used as a replacement for more conventional organic solvents in the extraction of biomolecules from a range of matrices. Supercritical fluid extraction of essential fatty acids from fish oils is discussed. Supercritical CO2 was used to fractionate two fatty acids, EPA and DHA from fish oil ethyl esters. EPA and DHA were obtained with a purity of 58% and 67% respectively from Sardine oil with an original composition of 17% and 12%. PMID:7763846

  5. Of Tangerines, Asparagus, and Nonprotein Biomolecules.

    Science.gov (United States)

    2016-05-19

    Every month the editors of Cell Chemical Biology bring you highlights of the most recent chemical biology literature. Our May 2016 selection includes a new method for labeling and visualizing nonprotein biomolecules using electron microscopy; a small molecule, originally found in tangerine peel, that regulates our circadian clock and helps with some of the metabolic pathologies associated with circadian rhythms; and a finding that asparagine is used as an amino acid exchanger in tumor cells. PMID:27203369

  6. Reaction between protein radicals and other biomolecules

    DEFF Research Database (Denmark)

    Østdal, Henrik; Davies, Michael Jonathan; Andersen, Henrik J

    2002-01-01

    The present study investigates the reactivity of bovine serum albumin (BSA) radicals towards different biomolecules (urate, linoleic acid, and a polypeptide, poly(Glu-Ala-Tyr)). The BSA radical was formed at room temperature through a direct protein-to-protein radical transfer from H(2)O(2....... Subsequent analysis showed a decrease in the concentration of urate upon reaction with the BSA radical, while the BSA radical in the presence of poly(Glu-Ala-Tyr) resulted in increased formation of the characteristic protein oxidation product, dityrosine. Reaction between the BSA radical and a linoleic acid...

  7. Porous solid ion exchange wafer for immobilizing biomolecules

    Science.gov (United States)

    Arora, Michelle B.; Hestekin, Jamie A.; Lin, YuPo J.; St. Martin, Edward J.; Snyder, Seth W.

    2007-12-11

    A porous solid ion exchange wafer having a combination of a biomolecule capture-resin and an ion-exchange resin forming a charged capture resin within said wafer. Also disclosed is a porous solid ion exchange wafer having a combination of a biomolecule capture-resin and an ion-exchange resin forming a charged capture resin within said wafer containing a biomolecule with a tag. A separate bioreactor is also disclosed incorporating the wafer described above.

  8. Shock Syntheses of Novel Nitrides and Biomolecules

    Science.gov (United States)

    Sekine, Toshimori

    2013-06-01

    High-pressure spinel nitride of Si3N4 was discovered more than 10 years ago. Since then there have been many studies on the spinel nitrides and related materials including oxynitrides. We have developed shock synthesis method to investigate their structural, mechanical, chemical, physical, and optical properties. At the same time we tried to synthesize carbon nitrides from the organic substances. And later we extended to shock synthesis of ammonia through the Haber-Bosch reaction under shock in order to apply geochemical subjects related to the origin of life. The simplest amino acid of glycine, as well as animes (up to propylamine) and carboxylic acids (up to pentanoic acid), has been synthesized successfully in aqueous solutions through meteoritic impact reactions. Recently we are trying to make more complex biomolecules for implications of biomolecule formation for the origin of life through meteorite impacts on early Earth's ocean. These results of shock syntheses may imply significant contributions to materials science and Earth and planetary sciences. This research is collaborated with National Institute for Materials Science and Tohoku University.

  9. Thermally modulated biomolecule transport through nanoconfined channels

    Science.gov (United States)

    Liu, Lei; Zhu, Lizhong

    2015-04-01

    In this work, a nanofluidic device containing both a feed cell and a permeation cell linked by nanopore arrays has been fabricated, which is employed to investigate thermally controlled biomolecular transporting properties through confined nanochannels. The ionic currents modulated by the translocations of goat antibody to human immunoglobulin G (IgG) or bovine serum albumin (BSA) are recorded and analyzed. The results suggest that the modulation effect decreases with the electrolyte concentration increasing, while the effects generated by IgG translocation are more significant than that generated by BSA translocation. More importantly, there is a maximum decreasing value in each modulated current curve with biomolecule concentration increasing for thermally induced intermolecular collision. Furthermore, the turning point for the maximum shifts to lower biomolecule concentrations with the system temperature rising (from 4°C to 45°C), and it is mainly determined by the temperature in the feed cell if the temperature difference exists in the two separated cells. These findings are expected to be valuable for the future design of novel sensing device based on nanopore and/or nanopore arrays.

  10. Production of teaching materials of nuclear medicine for use in career of Imagenologia Diagnostica y Terapeutica of the Escuela de Tecnologias de Salud of the Universidad de Costa Rica

    International Nuclear Information System (INIS)

    One of the main obstacles in the career of Imagenologia Diagnostica y Terapeutica of the Escuela de Tecnologias de Salud of the Universidad de Costa Rica has been access to bibliographic material of reference in Spanish. The topics most relevant of nuclear medicine of interest to imaging specialist and other disciplines as: medicine, physics, pharmacy and nursing, have been identified for the purpose of having a bibliographic body; experts have reviewed the selection in each subject. Topics of interest were identified and grouped into five specific teaching areas: 1. Radiation protection, 2. Quality Control of Nuclear Medicine Instruments, 3. Radiopharmacy, 4. Planar Nuclear Medicine, 5. Nuclear Medicine SPECT and PET. (author)

  11. Bioconjugation and stabilisation of biomolecules in biosensors.

    Science.gov (United States)

    Liébana, Susana; Drago, Guido A

    2016-06-30

    Suitable bioconjugation strategies and stabilisation of biomolecules on electrodes is essential for the development of novel and commercially viable biosensors. In the present review, the functional groups that comprise the selectable targets for practical bioconjugation methods are discussed. We focus on describing the most common immobilisation techniques used in biosensor construction, which are classified into irreversible and reversible methods. Concerning the stability of proteins, the two main types of stability may be defined as (i) storage or shelf stability, and (ii) operational stability. Both types of stability are explained, as well as the introduction of an electrophoretic technique for predicting protein-polymer interactions. In addition, solution and dry stabilisation as well as stabilisation using the covalent immobilisation of proteins are discussed including possible factors that influence stability. Finally, the integration of nanomaterials, such as magnetic particles, with protein immobilisation is discussed in relation to protein stability studies. PMID:27365036

  12. 'Smartening' anticancer therapeutic nanosystems using biomolecules.

    Science.gov (United States)

    Núñez-Lozano, Rebeca; Cano, Manuel; Pimentel, Belén; de la Cueva-Méndez, Guillermo

    2015-12-01

    To be effective, anticancer agents must induce cell killing in a selective manner, something that is proving difficult to achieve. Drug delivery systems could help to solve problems associated with the lack of selectivity of classical chemotherapeutic agents. However, to realize this, such systems must overcome multiple physiological barriers. For instance, they must evade surveillance by the immune system, attach selectively to target cells, and gain access to their interior. Furthermore, there they must escape endosomal entrapment, and release their cargoes in a controlled manner, without affecting their functionality. Here we review recent efforts aiming at using biomolecules to confer these abilities to bare nanoparticles, to transform them into smart anticancer therapeutic nanosystems. PMID:26277646

  13. Ionic strength independence of charge distributions in solvation of biomolecules.

    Science.gov (United States)

    Virtanen, J J; Sosnick, T R; Freed, K F

    2014-12-14

    Electrostatic forces enormously impact the structure, interactions, and function of biomolecules. We perform all-atom molecular dynamics simulations for 5 proteins and 5 RNAs to determine the dependence on ionic strength of the ion and water charge distributions surrounding the biomolecules, as well as the contributions of ions to the electrostatic free energy of interaction between the biomolecule and the surrounding salt solution (for a total of 40 different biomolecule/solvent combinations). Although water provides the dominant contribution to the charge density distribution and to the electrostatic potential even in 1M NaCl solutions, the contributions of water molecules and of ions to the total electrostatic interaction free energy with the solvated biomolecule are comparable. The electrostatic biomolecule/solvent interaction energies and the total charge distribution exhibit a remarkable insensitivity to salt concentrations over a huge range of salt concentrations (20 mM to 1M NaCl). The electrostatic potentials near the biomolecule's surface obtained from the MD simulations differ markedly, as expected, from the potentials predicted by continuum dielectric models, even though the total electrostatic interaction free energies are within 11% of each other. PMID:25494774

  14. Noncovalent Labeling of Biomolecules with Red and Near- Infrared Dyes

    Directory of Open Access Journals (Sweden)

    Lucjan Strekowski

    2004-02-01

    Full Text Available Biopolymers such as proteins and nucleic acids can be labeled with a fluorescent marker to allow for their detection. Covalent labeling is achieved by the reaction of an appropriately functionalized dye marker with a reactive group on a biomolecule. The recent trend, however, is the use of noncovalent labeling that results from strong hydrophobic and/or ionic interactions between the marker and biomolecule of interest. The main advantage of noncovalent labeling is that it affects the functional activity of the biomolecule to a lesser extent. The applications of luminescent cyanine and squarylium dyes are reviewed.

  15. Microfluidic Radiometal Labeling Systems for Biomolecules

    Energy Technology Data Exchange (ETDEWEB)

    Reichert, D E; Kenis, P J. A.

    2011-12-29

    In a typical labeling procedure with radiometals, such as Cu-64 and Ga-68; a very large (~ 100-fold) excess of the non-radioactive reactant (precursor) is used to promote rapid and efficient incorporation of the radioisotope into the PET imaging agent. In order to achieve high specific activities, careful control of reaction conditions and extensive chromatographic purifications are required in order to separate the labeled compounds from the cold precursors. Here we propose a microfluidic approach to overcome these problems, and achieve high specific activities in a more convenient, semi-automated fashion and faster time frame. Microfluidic reactors, consisting of a network of micron-sized channels (typical dimensions in the range 10 - 300¼m), filters, separation columns, electrodes and reaction loops/chambers etched onto a solid substrate, are now emerging as an extremely useful technology for the intensification and miniaturization of chemical processes. The ability to manipulate, process and analyze reagent concentrations and reaction interfaces in both space and time within the channel network of a microreactor provides the fine level of reaction control that is desirable in PET radiochemistry practice. These factors can bring radiometal labeling, specifically the preparation of radio-labeled biomolecules such as antibodies, much closer to their theoretical maximum specific activities.

  16. Cell and biomolecule delivery for regenerative medicine

    International Nuclear Information System (INIS)

    Regenerative medicine is an exciting field that aims to create regenerative alternatives to harvest tissues for transplantation. In this approach, the delivery of cells and biological molecules plays a central role. The scaffold (synthetic temporary extracellular matrix) delivers cells to the regenerative site and provides three-dimensional environments for the cells. To fulfil these functions, we design biodegradable polymer scaffolds with structural features on multiple size scales. To enhance positive cell-material interactions, we design nano-sized structural features in the scaffolds to mimic the natural extracellular matrix. We also integrate micro-sized pore networks to facilitate mass transport and neo tissue regeneration. We also design novel polymer devices and self-assembled nanospheres for biomolecule delivery to recapitulate key events in developmental and wound healing processes. Herein, we present recent work in biomedical polymer synthesis, novel processing techniques, surface engineering and biologic delivery. Examples of enhanced cellular/tissue function and regenerative outcomes of these approaches are discussed to demonstrate the excitement of the biomimetic scaffold design and biologic delivery in regenerative medicine. (topical review)

  17. Cell and biomolecule delivery for regenerative medicine

    Directory of Open Access Journals (Sweden)

    Ian O Smith and Peter X Ma

    2010-01-01

    Full Text Available Regenerative medicine is an exciting field that aims to create regenerative alternatives to harvest tissues for transplantation. In this approach, the delivery of cells and biological molecules plays a central role. The scaffold (synthetic temporary extracellular matrix delivers cells to the regenerative site and provides three-dimensional environments for the cells. To fulfil these functions, we design biodegradable polymer scaffolds with structural features on multiple size scales. To enhance positive cell–material interactions, we design nano-sized structural features in the scaffolds to mimic the natural extracellular matrix. We also integrate micro-sized pore networks to facilitate mass transport and neo tissue regeneration. We also design novel polymer devices and self-assembled nanospheres for biomolecule delivery to recapitulate key events in developmental and wound healing processes. Herein, we present recent work in biomedical polymer synthesis, novel processing techniques, surface engineering and biologic delivery. Examples of enhanced cellular/tissue function and regenerative outcomes of these approaches are discussed to demonstrate the excitement of the biomimetic scaffold design and biologic delivery in regenerative medicine.

  18. Active immobilization of biomolecules on a hybrid three-dimensional nanoelectrode by dielectrophoresis for single-biomolecule study

    International Nuclear Information System (INIS)

    We propose and experimentally demonstrate a method of active immobilization for biomolecules on a three-dimensional nanometre-scale electrode (3D nanoelectrode) using dielectrophoresis to immobilize the biomolecules at predetermined locations for single-biomolecule study. We have developed a novel two-step fabrication process for obtaining a 3D nanoelectrode having a sharp top, which is necessary for immobilizing a single biomolecule at a single point. The first step is to fabricate the backbone structure, which is rigid and defines the shape of the 3D nanoelectrode. It was fabricated with diamond-like carbon (DLC) obtained using focused ion beam assisted chemical vapour deposition followed by post-plasma etching, which reshapes the DLC structure. The second step coats the DLC structure with a thin layer of aluminium, which supplies electrical conductivity to the DLC structure. By applying a high frequency (of the order of megahertz) and high intensity (greater than or equal to a few megavolts per metre) electric field using the 3D nanoelectrodes, the generated dielectrophoresis attracted and then immobilized target biomolecules onto the tops of 3D nanoelectrodes, as a demonstration of active immobilization of biomolecules

  19. Production of biomolecule microarrays through laser induced forward transfer

    Science.gov (United States)

    Fernandez-Pradas, Juan Marcos; Serra, Pere; Colina, Monica; Morenza, Jose-Luis

    2004-10-01

    Biomolecule microarrays are a kind of biosensors that consist in patterns of different biological molecules immobilized on a solid substrate and capable to bind specifically to their complementary targets. In particular, DNA and protein microarrays have been revealed to be very efficient devices for genen and protein identification, what has converted them in powerful tools for many applications, like clinical diagnose, drug discovery analysis, genomics and proteomics. The production of these devices requires the manipulation of tiny amounts of a liquid solution containing biomolecules without damaging them. In this work laser induced forward transfer (LIFT) has been used for spotting a biomolecule in order to check the viability of this technique for the production of microarrays. A pulsed Nd:YAG laser beam (355 nm wavelength) has been used to transfer droplets of a biomolecule containing solution onto a solid slide. Optical microscopy of the transferred material has been carried out to investigate the morphological characteristics of the droplets obtained under different irradiation conditions. Afterwards, a DNA microarray has been spotted. The viability of the transference has been tested by checking the biological activity of the biomolecule in front of its specific complementary target. This has revealed that, indeed, the LIFT technique is adequate for the production of DNA microarrays.

  20. Constraint methods that accelerate free-energy simulations of biomolecules

    International Nuclear Information System (INIS)

    Atomistic molecular dynamics simulations of biomolecules are critical for generating narratives about biological mechanisms. The power of atomistic simulations is that these are physics-based methods that satisfy Boltzmann’s law, so they can be used to compute populations, dynamics, and mechanisms. But physical simulations are computationally intensive and do not scale well to the sizes of many important biomolecules. One way to speed up physical simulations is by coarse-graining the potential function. Another way is to harness structural knowledge, often by imposing spring-like restraints. But harnessing external knowledge in physical simulations is problematic because knowledge, data, or hunches have errors, noise, and combinatoric uncertainties. Here, we review recent principled methods for imposing restraints to speed up physics-based molecular simulations that promise to scale to larger biomolecules and motions

  1. Kinetic analysis of interaction between lipopolysaccharide and biomolecules

    Institute of Scientific and Technical Information of China (English)

    Fan YANG; Xiurong YANG

    2008-01-01

    Lipopolysaccharide (LPS) is a major compo-nent of the outer membrane of all gram-negative bacteria. It interacts with some biomolecules and triggers a toxic reaction. In this paper, we studied the interaction between LPS from Salmonella Minnesota and some biomolecules using a surface plasmon resonance (SPR) biosensor. Biomolecules were immobilized on a CM5 sensor chip using the amino coupling method and LPS was injected over the immobilized surfaces. The affinity constant KA of LPS with serum albumin, hemoglobin, chitosan and lysozyme was 2.36 × 107, 2.03 × 108,7.58×106, 2.82 × 104 L·mol-1, respectively. However, LPS could not interact with ferritin.

  2. Identification of biomolecules by terahertz spectroscopy and fuzzy pattern recognition

    Science.gov (United States)

    Chen, Tao; Li, Zhi; Mo, Wei

    2013-04-01

    An approach for automatic identification of terahertz (THz) spectra of biomolecules is proposed based on principal component analysis (PCA) and fuzzy pattern recognition in this paper, and THz transmittance spectra of some typical amino acid and saccharide biomolecular samples are investigated to prove its feasibility. Firstly, PCA is applied to reduce the dimensionality of the original spectrum data and extract features of the data. Secondly, instead of the original spectrum variables, the selected principal component scores matrix is fed into the model of fuzzy pattern recognition, where a principle of fuzzy closeness based optimization is employed to identify those samples. Results demonstrate that THz spectroscopy combined with PCA and fuzzy pattern recognition can be efficiently utilized for automatic identification of biomolecules. The proposed approach provides a new effective method in the detection and identification of biomolecules using THz spectroscopy.

  3. Constraint methods that accelerate free-energy simulations of biomolecules

    Energy Technology Data Exchange (ETDEWEB)

    Perez, Alberto [Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, New York 11794 (United States); MacCallum, Justin L. [Department of Chemistry, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Coutsias, Evangelos A. [Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, New York 11794 (United States); Department of Applied Mathematics, Stony Brook University, Stony Brook, New York 11794 (United States); Dill, Ken A. [Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, New York 11794 (United States); Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794 (United States)

    2015-12-28

    Atomistic molecular dynamics simulations of biomolecules are critical for generating narratives about biological mechanisms. The power of atomistic simulations is that these are physics-based methods that satisfy Boltzmann’s law, so they can be used to compute populations, dynamics, and mechanisms. But physical simulations are computationally intensive and do not scale well to the sizes of many important biomolecules. One way to speed up physical simulations is by coarse-graining the potential function. Another way is to harness structural knowledge, often by imposing spring-like restraints. But harnessing external knowledge in physical simulations is problematic because knowledge, data, or hunches have errors, noise, and combinatoric uncertainties. Here, we review recent principled methods for imposing restraints to speed up physics-based molecular simulations that promise to scale to larger biomolecules and motions.

  4. Necrotizing fasciitis of soft tissues. Diagnostic imaging findings and literature review; Le fascite necrotizzante dei tessuti molli. Ruolo della diagnostica per immagini e revisione della letteratura

    Energy Technology Data Exchange (ETDEWEB)

    Parenti, G.C.; Marri, C. [Ospedale Civile S. Maria delle Croci, Ravenna (Italy). Servizio di Radiodiagnostica; Calandra, G. [Ospedale Civile S. Maria delle Croci, Ravenna (Italy). Unita' operativa di Pronto Soccorso; Morisi, C. [Ospedale Civile S. Maria delle Croci, Ravenna (Italy). Servizio di Anatomia Patologica; Zabberoni, W. [Ospedale Civile S. Maria delle Croci, Ravenna (Italy). Div. di Malattie Infettive, Gruppo di rilevamento dati sulle INPS-ASL

    2000-05-01

    maggio 1991 a febbraio 1998 sono giunti alla nostra osservazione 130 casi di infezioni necrotizzanti progressive dei tessuti molli; in 32 casi l'eta' era compresa fra 22 e 84 anni; la diagnosi istologica retrospettiva e' risultata quella della fascite necrotizzante. Le sedi interessate dal processo sono state: arti (26/32), regioni cervicale (5/32) e perineale (1/32). Diciannove pazienti (19/32) sono stati sottoposti d'urgenza a esame radiografico eseguito anche per lo studio dei tessuti molli. L'esame ecografico e' stato eseguito d'urgenza in tutti i 32 pazienti. La valutazione dei pazienti con sospetto di infezioni necrosanti progressive e' affidata di solito a un gruppo di operatori esperti in diagnostica ecografica dei tessuti molli perischeletrici. L'esame TC e' stato eseguito in 9 casi (9/32); a ognuno di questi pazienti e' stato somministrato mdc iodato per via endovenosa. Con gli esami ecografico ed eco color Doppler, nel sospetto di fascite necrotizzante, e' possibile offrire indicazioni utili e affidabili per il corretto e rapido orientamento diagnostico; in particolare tale metodica e' in grado di rilevare precocemente alterazioni al tessuto adiposo sottocutaneo (28/32), alla fascia (18/32) e al tessuto molecolare (15/32). E' stata riscontrata buona correlazione tra alterazione tissutale rilevata con l'esame ecografico e reperto istologico; l'ecografia non ha evidenziato alterazioni al tessuto adiposo sottocutaneo (3/32) e al tessuto molecolare (8/32) in 11 casi pur evidenti all'esame istologico. La TC con mdc puo' essere utile per la migliore definizione dell'estensione della malattia e per la dimostrazione di eventuali complicanze, soprattutto in sedi difficili da raggiungere con l'ecografia. Le probabilita' di guarigione per i pazienti affetti da fascite necrotizzante sono direttamente proporzionali alla precocita' della diagnosi e all

  5. Understanding small biomolecule-biomaterial interactions: a review of fundamental theoretical and experimental approaches for biomolecule interactions with inorganic surfaces.

    Science.gov (United States)

    Costa, Dominique; Garrain, Pierre-Alain; Baaden, Marc

    2013-04-01

    Interactions between biomolecules and inorganic surfaces play an important role in natural environments and in industry, including a wide variety of conditions: marine environment, ship hulls (fouling), water treatment, heat exchange, membrane separation, soils, mineral particles at the earth's surface, hospitals (hygiene), art and buildings (degradation and biocorrosion), paper industry (fouling) and more. To better control the first steps leading to adsorption of a biomolecule on an inorganic surface, it is mandatory to understand the adsorption mechanisms of biomolecules of several sizes at the atomic scale, that is, the nature of the chemical interaction between the biomolecule and the surface and the resulting biomolecule conformations once adsorbed at the surface. This remains a challenging and unsolved problem. Here, we review the state of art in experimental and theoretical approaches. We focus on metallic biomaterial surfaces such as TiO(2) and stainless steel, mentioning some remarkable results on hydroxyapatite. Experimental techniques include atomic force microscopy, surface plasmon resonance, quartz crystal microbalance, X-ray photoelectron spectroscopy, fluorescence microscopy, polarization modulation infrared reflection absorption spectroscopy, sum frequency generation and time of flight secondary ion mass spectroscopy. Theoretical models range from detailed quantum mechanical representations to classical forcefield-based approaches. PMID:23015529

  6. Quantum chemistry and charge transport in biomolecules with superconducting circuits

    Science.gov (United States)

    García-Álvarez, L.; Las Heras, U.; Mezzacapo, A.; Sanz, M.; Solano, E.; Lamata, L.

    2016-06-01

    We propose an efficient protocol for digital quantum simulation of quantum chemistry problems and enhanced digital-analog quantum simulation of transport phenomena in biomolecules with superconducting circuits. Along these lines, we optimally digitize fermionic models of molecular structure with single-qubit and two-qubit gates, by means of Trotter-Suzuki decomposition and Jordan-Wigner transformation. Furthermore, we address the modelling of system-environment interactions of biomolecules involving bosonic degrees of freedom with a digital-analog approach. Finally, we consider gate-truncated quantum algorithms to allow the study of environmental effects.

  7. Quantum chemistry and charge transport in biomolecules with superconducting circuits

    Science.gov (United States)

    García-Álvarez, L.; Las Heras, U.; Mezzacapo, A.; Sanz, M.; Solano, E.; Lamata, L.

    2016-01-01

    We propose an efficient protocol for digital quantum simulation of quantum chemistry problems and enhanced digital-analog quantum simulation of transport phenomena in biomolecules with superconducting circuits. Along these lines, we optimally digitize fermionic models of molecular structure with single-qubit and two-qubit gates, by means of Trotter-Suzuki decomposition and Jordan-Wigner transformation. Furthermore, we address the modelling of system-environment interactions of biomolecules involving bosonic degrees of freedom with a digital-analog approach. Finally, we consider gate-truncated quantum algorithms to allow the study of environmental effects. PMID:27324814

  8. Recovery of Biomolecules from Food Wastes — A Review

    Directory of Open Access Journals (Sweden)

    Antonietta Baiano

    2014-09-01

    Full Text Available Food wastes are produced by a variety of sources, ranging from agricultural operations to household consumption. About 38% occurs during food processing. At present, the European Union legislation encourages the exploitation of co-products. This valorisation can be achieved through the extraction of high-value components such as proteins, polysaccharides, fibres, flavour compounds, and phytochemicals, which can be re-used as nutritionally and pharmacologically functional ingredients. Extraction can proceed according to solid-liquid extraction, Soxhlet extraction, pressurized fluid extraction, supercritical fluid extraction, ultrasound-assisted extraction, microwave-assisted extraction, pulsed electric field extraction, and enzyme-assisted extraction. Nevertheless, these techniques cannot be used indiscriminately and their choice depends on the type of biomolecules and matrix, the scale processing (laboratory or industrial, the ratio between production costs and economic values of the compounds to be extracted. The vegetable wastes include trimmings, peelings, stems, seeds, shells, bran, residues remaining after extraction of oil, starch, sugar, and juice. The animal-derived wastes include wastes from bred animals, wastes from seafood, wastes from dairy processing. The recovered biomolecules and by-products can be used to produce functional foods or as adjuvants in food processing or in medicinal and pharmaceutical preparations. This work is an overview of the type and amounts of food wastes; food waste legislation; conventional and novel techniques suitable for extracting biomolecules; food, medicinal and pharmaceutical uses of the recovered biomolecules and by-products, and future trends in these areas.

  9. Photochemical Microscale Electrophoresis Allows Fast Quantification of Biomolecule Binding.

    Science.gov (United States)

    Möller, Friederike M; Kieß, Michael; Braun, Dieter

    2016-04-27

    Intricate spatiotemporal patterns emerge when chemical reactions couple to physical transport. We induce electrophoretic transport by a confined photochemical reaction and use it to infer the binding strength of a second, biomolecular binding reaction under physiological conditions. To this end, we use the photoactive compound 2-nitrobenzaldehyde, which releases a proton upon 375 nm irradiation. The charged photoproducts locally perturb electroneutrality due to differential diffusion, giving rise to an electric potential Φ in the 100 μV range on the micrometer scale. Electrophoresis of biomolecules in this field is counterbalanced by back-diffusion within seconds. The biomolecule concentration is measured by fluorescence and settles proportionally to exp(-μ/D Φ). Typically, binding alters either the diffusion coefficient D or the electrophoretic mobility μ. Hence, the local biomolecule fluorescence directly reflects the binding state. A fit to the law of mass action reveals the dissociation constant of the binding reaction. We apply this approach to quantify the binding of the aptamer TBA15 to its protein target human-α-thrombin and to probe the hybridization of DNA. Dissociation constants in the nanomolar regime were determined and match both results in literature and in control experiments using microscale thermophoresis. As our approach is all-optical, isothermal and requires only nanoliter volumes at nanomolar concentrations, it will allow for the fast screening of biomolecule binding in low volume multiwell formats. PMID:27042755

  10. Recovery of biomolecules from food wastes--a review.

    Science.gov (United States)

    Baiano, Antonietta

    2014-01-01

    Food wastes are produced by a variety of sources, ranging from agricultural operations to household consumption. About 38% occurs during food processing. At present, the European Union legislation encourages the exploitation of co-products. This valorisation can be achieved through the extraction of high-value components such as proteins, polysaccharides, fibres, flavour compounds, and phytochemicals, which can be re-used as nutritionally and pharmacologically functional ingredients. Extraction can proceed according to solid-liquid extraction, Soxhlet extraction, pressurized fluid extraction, supercritical fluid extraction, ultrasound-assisted extraction, microwave-assisted extraction, pulsed electric field extraction, and enzyme-assisted extraction. Nevertheless, these techniques cannot be used indiscriminately and their choice depends on the type of biomolecules and matrix, the scale processing (laboratory or industrial), the ratio between production costs and economic values of the compounds to be extracted. The vegetable wastes include trimmings, peelings, stems, seeds, shells, bran, residues remaining after extraction of oil, starch, sugar, and juice. The animal-derived wastes include wastes from bred animals, wastes from seafood, wastes from dairy processing. The recovered biomolecules and by-products can be used to produce functional foods or as adjuvants in food processing or in medicinal and pharmaceutical preparations. This work is an overview of the type and amounts of food wastes; food waste legislation; conventional and novel techniques suitable for extracting biomolecules; food, medicinal and pharmaceutical uses of the recovered biomolecules and by-products, and future trends in these areas. PMID:25232705

  11. Fullerene–biomolecule conjugates and their biomedicinal applications

    Directory of Open Access Journals (Sweden)

    Yang X

    2013-12-01

    Full Text Available Xinlin Yang,1 Ali Ebrahimi,1 Jie Li,1,2 Quanjun Cui11Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Virginia School of Medicine, Charlottesville, VA, USA; 2School of Materials Science, Beijing Institute of Technology, Beijing, People's Republic of ChinaAbstract: Fullerenes are among the strongest antioxidants and are characterized as "radical sponges." The research on biomedicinal applications of fullerenes has achieved significant progress since the landmark publication by Friedman et al in 1993. Fullerene–biomolecule conjugates have become an important area of research during the past 2 decades. By a thorough literature search, we attempt to update the information about the synthesis of different types of fullerene–biomolecule conjugates, including fullerene-containing amino acids and peptides, oligonucleotides, sugars, and esters. Moreover, we also discuss in this review recently reported data on the biological and pharmaceutical utilities of these compounds and some other fullerene derivatives of biomedical importance. While within the fullerene–biomolecule conjugates, in which fullerene may act as both an antioxidant and a carrier, specific targeting biomolecules conjugated to fullerene will undoubtedly strengthen the delivery of functional fullerenes to sites of clinical interest.Keywords: fullerene, amino acid, peptide, oligonucleotide, sugar, ester

  12. Solvation dynamics of biomolecules: modeling and terahertz experiments.

    Science.gov (United States)

    Leitner, David M; Gruebele, Martin; Havenith, Martina

    2008-12-01

    The role of water in biomolecule dynamics has attracted much interest over the past decade, due in part to new probes of biomolecule-water interactions and developments in molecular simulations. Terahertz (THz) spectroscopy, among the most recent experimental methods brought to bear on this problem, is able to detect even small solute induced changes of the collective water network dynamics at the biomolecule-water interface. THz measurements reveal that proteins influence up to 1000 water molecules in their surroundings, and that even small saccharides influence the dynamics of hundreds of surrounding water molecules. The THz spectrum of a protein is sensitive to mutation and depends on the surface charge and flexibility of the protein. Influence on the solvation shell appears most pronounced for native wildtype proteins and decreases upon partial unfolding or mutation. THz spectra of solvated saccharides reveal that the number of water molecules coupled dynamically to a saccharide, forming a dynamical hydration shell around it, is related to the number of exposed oxygen atoms on the solute. The thickness of this layer appears correlated with the bioprotection efficiency of the saccharide. All findings support the thesis of a long-range dynamic coupling between biomolecule and solvent. PMID:19436490

  13. Carioca: a perspectiva da enfermagem

    Directory of Open Access Journals (Sweden)

    Ana Elisa Fernandes Lima

    2015-01-01

    Full Text Available Objetivo: describir las acciones recomendadas por el Programa Cigüeña Carioca para atención a las parturientes y determinar si la aplicación de este Programa tuvo repercusiones en esta asistencia desde la perspectiva del equipo de enfermería. Métodos: estudio descriptivo, con abordaje cualitativo, realizado en una maternidad pública. Entrevistas semiestructuradas se realizaron con cuatro enfermeras obstétricas y siete auxiliares de enfermería que trabajan en el centro de obstetricia de la maternidad. Se utilizó la técnica de análisis de contenido temático. Resultados: las categorías del estudio fueron: Calificación de la atención obstétrica hospitalaria y Repercusiones asistenciales y profesionales del Programa Cigüeña Carioca. Conclusión: el personal de enfermería consideró que la aplicación del Programa ha traído mejoras en la atención al parto, favoreciendo la garantía de los derechos de la mujer y el cumplimiento de la enfermería obstétrica en la red de salud municipal.

  14. Realismo moral: una perspectiva naturalista

    Directory of Open Access Journals (Sweden)

    Michael Devitt

    2004-12-01

    Full Text Available 1. ¿Qué es el realismo moral? El artículo rechaza las respuestas habituales (Sayre-McCord, Railton en términos de verdad y significado. Estas respuestas estándares están parcialmente motivadas por el fenómeno del no-cognitivismo. Ciertamente el no-cognitivismo es problemático para formular una respuesta abiertamente metafísica, no obstante es posibleformular tal respuesta. 2. ¿Por qué creer en el realismo moral? Él es prima facie plausible, mientras que sus alternativas no lo son. Preocupación central: ¿cómo se puede lograr que el realismo moral coincida con una perspectiva naturalista del mundo? 3. ¿Y qué sucede con los argumentos en contra del realismo moral? El artículo analiza críticamente el argumentoproveniente de la “extrañeza”, el proveniente de la relatividad, el proveniente de la explicación, así como los argumentos epistemológicos. 4. El artículo concluye con algunas observaciones breves e insuficientes sobre la realización del proyecto naturalista.

  15. The theory and effect of solvent environment on biomolecules

    Science.gov (United States)

    Schnieders, Michael J.

    This dissertation describes the theory and effect of solvent environment on biomolecules using a computational model known as a force field. Force fields are based on formulating an efficient, empirical function of atomic coordinates designed to reproduce the potential energy surface predicted by the more rigorous, but also intractably expensive Schrodinger equation. In particular, this work is novel due to use of an Atomic Multipole Optimized Energetics for Biomolecular Applications (AMOEBA) force field that represents charge density using polarizable atomic multipoles. Polarizable Multipole Poisson-Boltzmann (PMPB) and generalized Kirkwood (GK) continuum electrostatics models are described that interact self-consistently with AMOEBA biomolecules. In conjunction with a novel apolar estimator, the PMPB and GK models are used to construct two implicit solvents for solutes represented by the AMOEBA force field. The effect of solvent environment on the electrostatic moments of a large set of folded proteins is examined.

  16. An overview: biomolecules from microalgae for animal feed and aquaculture.

    Science.gov (United States)

    Yaakob, Zahira; Ali, Ehsan; Zainal, Afifi; Mohamad, Masita; Takriff, Mohd Sobri

    2014-12-01

    Despite being more popular for biofuel, microalgae have gained a lot of attention as a source of biomolecules and biomass for feed purposes. Algae farming can be established using land as well as sea and strategies can be designed in order to gain the products of specific interest in the optimal way. A general overview of the contributions of Algae to meet the requirements of nutrients in animal/aquaculture feed is presented in this study. In addition to its applications in animal/aquaculture feed, algae can produce a number of biomolecules including astaxanthin, lutein, beta-carotene, chlorophyll, phycobiliprotein, Polyunsaturated Fatty Acids (PUFAs), beta-1,3-glucan, and pharmaceutical and nutraceutical compounds which have been reviewed with respect to their commercial importance and current status. The review is further extended to highlight the adequate utilization of value added products in the feeds for livestock, poultry and aquaculture (with emphasis in shrimp farming). PMID:25984489

  17. Antifouling self-assembled monolayers on microelectrodes for patterning biomolecules.

    Science.gov (United States)

    Noel, John; Teizer, Winfried; Hwang, Wonmuk

    2009-01-01

    We present a procedure for forming a poly(ethylene glycol) (PEG) trimethoxysilane self-assembled monolayer (SAM) on a silicon substrate with gold microelectrodes. The PEG-SAM is formed in a single assembly step and prevents biofouling on silicon and gold surfaces. The SAM is used to coat microelectrodes patterned with standard, positive-tone lithography. Using the microtubule as an example, we apply a DC voltage to induce electrophoretic migration to the SAM-coated electrode in a reversible manner. A flow chamber is used for imaging the electrophoretic migration and microtubule patterning in situ using epifluorescence microscopy. This method is generally applicable to biomolecule patterning, as it employs electrophoresis to immobilize target molecules and thus does not require specific molecular interactions. Further, it avoids problems encountered when attempting to pattern the SAM molecules directly using lithographic techniques. The compatibility with electron beam lithography allows this method to be used to pattern biomolecules at the nanoscale. PMID:19707178

  18. Models for Energy and Charge Transport, and Storage in Biomolecules

    CERN Document Server

    Mingaleev, S F; Gaididei, Yu B; Johansson, M; Rasmussen, K O; Mingaleev, Serge F.; Christiansen, Peter L.; Gaididei, Yuri B.; Johansson, Magnus; Rasmussen, Kim O.

    1999-01-01

    Two models for energy and charge transport and storage in biomolecules are considered. A model based on the discrete nonlinear Schrodinger equation with long-range dispersive interactions (LRI's) between base pairs of DNA is offered for the description of nonlinear dynamics of the DNA molecule. We show that LRI's are responsible for the existence of an interval of bistability where two stable stationary states, a narrow, pinned state and a broad, mobile state, coexist at each value of the total energy. The possibility of controlled switching between pinned and mobile states is demonstrated. The mechanism could be important for controlling energy storage and transport in DNA molecules. Another model is offered for the description of nonlinear excitations in proteins and other anharmonic biomolecules. We show that in the highly anharmonic systems a bound state of Davydov and Boussinesq solitons can exist.

  19. Immobilization of different biomolecules by atomic force microscopy

    Directory of Open Access Journals (Sweden)

    Hölzel Ralph

    2010-05-01

    Full Text Available Abstract Background Micrometer resolution placement and immobilization of probe molecules is an important step in the preparation of biochips and a wide range of lab-on-chip systems. Most known methods for such a deposition of several different substances are costly and only suitable for a limited number of probes. In this article we present a flexible procedure for simultaneous spatially controlled immobilization of functional biomolecules by molecular ink lithography. Results For the bottom-up fabrication of surface bound nanostructures a universal method is presented that allows the immobilization of different types of biomolecules with micrometer resolution. A supporting surface is biotinylated and streptavidin molecules are deposited with an AFM (atomic force microscope tip at distinct positions. Subsequent incubation with a biotinylated molecule species leads to binding only at these positions. After washing streptavidin is deposited a second time with the same AFM tip and then a second biotinylated molecule species is coupled by incubation. This procedure can be repeated several times. Here we show how to immobilize different types of biomolecules in an arbitrary arrangement whereas most common methods can deposit only one type of molecules. The presented method works on transparent as well as on opaque substrates. The spatial resolution is better than 400 nm and is limited only by the AFM's positional accuracy after repeated z-cycles since all steps are performed in situ without moving the supporting surface. The principle is demonstrated by hybridization to different immobilized DNA oligomers and was validated by fluorescence microscopy. Conclusions The immobilization of different types of biomolecules in high-density microarrays is a challenging task for biotechnology. The method presented here not only allows for the deposition of DNA at submicrometer resolution but also for proteins and other molecules of biological relevance that

  20. Optical Sensors for Biomolecules Using Nanoporous Sol-Gel Materials

    Science.gov (United States)

    Fang, Jonathan; Zhou, Jing C.; Lan, Esther H.; Dunn, Bruce; Gillman, Patricia L.; Smith, Scott M.

    2004-01-01

    An important consideration for space missions to Mars is the ability to detect biosignatures. Solid-state sensing elements for optical detection of biological entities are possible using sol-gel based biologically active materials. We have used these materials as optical sensing elements in a variety of bioassays, including immunoassays and enzyme assays. By immobilizing an appropriate biomolecule in the sol-gel sensing element, we have successfully detected analytes such as amino acids and hormones. In the case of the amino acid glutamate, the enzyme glutamate dehydrogenase was the immobilized molecule, whereas in the case of the hormone cortisol, an anti-cortisol antibody was immobilized in the sensing element. In this previous work with immobilized enzymes and antibodies, excellent sensitivity and specificity were demonstrated in a variety of formats including bulk materials, thin films and fibers. We believe that the sol-gel approach is an attractive platform for bioastronautics sensing applications because of the ability to detect a wide range of entities such as amino acids, fatty acids, hopanes, porphyrins, etc. The sol-gel approach produces an optically transparent 3D silica matrix that forms around the biomolecule of interest, thus stabilizing its structure and functionality while allowing for optical detection. This encapsulation process protects the biomolecule and leads to a more "rugged" sensor. The nanoporous structure of the sol-gel matrix allows diffusion of small target molecules but keeps larger, biomolecules immobilized in the pores. We are currently developing these biologically active sol-gel materials into small portable devices for on-orbit cortisol detection

  1. Mapping the Chemical Universe of Biomolecules for Astrobiology

    OpenAIRE

    Meringer, Markus

    2015-01-01

    Understanding the origins of life is a central question of Astrobiology. Computer methods offer unique means to approach this challenge. In order to obtain a better understanding of the selection rules which guided chemical and early biochemical evolution, our approach is to computationally generate exhaustive sets of biomolecule analogues, to calculate their physico-chemical properties, and to simulate adaptive processes that might have led to the biochemical foundations of life as we know i...

  2. The first search for glycine and other biomolecules

    OpenAIRE

    Storey, J. W. V.

    2012-01-01

    In the 1970s the microwave spectroscopy group at Monash University became the first in the world to determine the spectral frequencies of urea, glycine, and several other biomolecules. We immediately searched for these at Parkes, using existing centimetre-wave receivers plus newly built receivers that operated at frequencies as high as 75GHz (and used just the central 17 m of the dish). Although these searches were largely unsuccessful, they helped launch the now flourishing field of astrobio...

  3. Models and algorithms for biomolecules and molecular networks

    CERN Document Server

    DasGupta, Bhaskar

    2016-01-01

    By providing expositions to modeling principles, theories, computational solutions, and open problems, this reference presents a full scope on relevant biological phenomena, modeling frameworks, technical challenges, and algorithms. * Up-to-date developments of structures of biomolecules, systems biology, advanced models, and algorithms * Sampling techniques for estimating evolutionary rates and generating molecular structures * Accurate computation of probability landscape of stochastic networks, solving discrete chemical master equations * End-of-chapter exercises

  4. Thermo-responsive hydrogels for intravitreal injection and biomolecule release

    Science.gov (United States)

    Drapala, Pawel

    In this dissertation, we develop an injectable polymer system to enable localized and prolonged release of therapeutic biomolecules for improved treatment of Age-Related Macular Degeneration (AMD). Thermo-responsive hydrogels derived from N-isopropylacrylamide (NIPAAm) and cross-linked with poly(ethylene glycol) (PEG) poly(L-Lactic acid) (PLLA) copolymer were synthesized via free-radical polymerization. These materials were investigated for (a) phase change behavior, (b) in-vitro degradation, (c) capacity for controlled drug delivery, and (d) biocompatibility. The volume-phase transition temperature (VPTT) of the PNIPAAm- co-PEG-b-PLLA hydrogels was adjusted using hydrophilic and hydrophobic moieties so that it is ca. 33°C. These hydrogels did not initially show evidence of degradation at 37°C due to physical cross-links of collapsed PNIPAAm. Only after addition of glutathione chain transfer agents (CTA)s to the precursor did the collapsed hydrogels become fully soluble at 37°C. CTAs significantly affected the release kinetics of biomolecules; addition of 1.0 mg/mL glutathione to 3 mM cross-linker accelerated hydrogel degradation, resulting in 100% release in less than 2 days. This work also explored the effect of PEGylation in order to tether biomolecules to the polymer matrix. It was demonstrated that non-site-specific PEGylation can postpone the burst release of solutes (up to 10 days in hydrogels with 0.5 mg/mL glutathione). Cell viability assays showed that at least two 20-minute buffer extraction steps were needed to remove cytotoxic elements from the hydrogels. Clinically-used therapeutic biomolecules LucentisRTM and AvastinRTM were demonstrated to be both stable and bioactive after release form PNIPAAm-co-PEG-b-PLLA hydrogels. The thermo-responsive hydrogels presented here offer a promising platform for the localized delivery of proteins such as recombinant antibodies.

  5. Spatially Controlled Covalent Immobilization of Biomolecules on Silicon Surfaces

    OpenAIRE

    Pavlovic, Elisabeth

    2003-01-01

    The work described in this thesis aims to achieving surface patterning through chemical activation of thiolated silicon oxide surfaces, resulting in a spatially controlled covalent immobilization of biomolecules with high resolution. Existing chemical methods to immobilize molecules on surfaces do not reach below the micrometer scale while the ones allowing for spatial control mostly lead to non-covalent adsorption of molecules on surfaces, or require several successive chemical reactions to ...

  6. Development of radioactively labelled cancer seeking biomolecules for targeted radiotherapy

    International Nuclear Information System (INIS)

    The main objective of this project is the labelling and quality control of biomolecules with radionuclides beta emitters with high purity and stability. Techniques and methodology for labelling with 188Re, 153Sm, and 125I as well as quality controls were done according the recommendations of the first research coordination meeting of this CRP. Also some useful chelators reported in the literature were synthesized in our laboratory

  7. The first search for glycine and other biomolecules

    CERN Document Server

    Storey, J W V

    2012-01-01

    In the 1970s the microwave spectroscopy group at Monash University became the first in the world to determine the spectral frequencies of urea, glycine, and several other biomolecules. We immediately searched for these at Parkes, using existing centimetre-wave receivers plus newly built receivers that operated at frequencies as high as 75GHz (and used just the central 17 m of the dish). Although these searches were largely unsuccessful, they helped launch the now flourishing field of astrobiology.

  8. Capillary Electrophoresis-based Methodology Development for Biomolecule Analysis

    OpenAIRE

    Li, Ni

    2011-01-01

    Capillary electrophoresis (CE) is a separation tool with wide applications in biomolecule analysis. Fast and high-resolution separation requiring minute sample volumes is advantageous to study multiple components in biological samples. Flexible modes and methods can be developed. In this thesis, I focus on developing and applying novel CE methods to study multi-target nucleic acid sensing with high sensitivity (Part I) and interactions between multiple components, i.e. proteins, nanoparticles...

  9. Renewable-Biomolecule-Based Full Lithium-Ion Batteries.

    Science.gov (United States)

    Hu, Pengfei; Wang, Hua; Yang, Yun; Yang, Jie; Lin, Jie; Guo, Lin

    2016-05-01

    A renewable-biomolecule-based full lithium-ion battery is successfully fabricated for the first time. Naturally derivable emodin and humic acid based electrodes are used as cathode and anode, respectively. The as-assembled batteries exhibit superb specific capacity and substantial operating voltage capable of powering a wearable electronic watch, suggesting the great potential for practical applications with the significant merits of sustainability and biocompatibility. PMID:26989989

  10. Solvent Influence on Photochemistry of Small Biomolecules in Clusters

    Czech Academy of Sciences Publication Activity Database

    Profant, V.; Dian, J.; Fárník, Michal; Poterya, Viktoriya

    Prague : MATFYZPRESS, 2008 - (Šafránková, J.; Pavlů, J.), s. 136-141 ISBN 978-80-7378-067-8. [Annual Conference of Doctoral Student /17./, WDS´08. Prague (CZ), 03.06.2008-06.06.2008] R&D Projects: GA ČR GA203/06/1290; GA AV ČR KAN400400651 Institutional research plan: CEZ:AV0Z40400503 Keywords : biomolecules * clusters * photochemistry Subject RIV: CF - Physical ; Theoretical Chemistry

  11. GroPBS: Fast Solver for Implicit Electrostatics of Biomolecules

    OpenAIRE

    Bertelshofer, Franziska; Sun, Liping; Greiner, Günther; Böckmann, Rainer A.

    2015-01-01

    Knowledge about the electrostatic potential on the surface of biomolecules or biomembranes under physiological conditions is an important step in the attempt to characterize the physico-chemical properties of these molecules and, in particular, also their interactions with each other. Additionally, knowledge about solution electrostatics may also guide the design of molecules with specified properties. However, explicit water models come at a high computational cost, rendering them unsuitable...

  12. Models for Energy and Charge Transport and Storage in Biomolecules

    OpenAIRE

    Mingaleev, S. F.; Christiansen, P. L.; Gaididei, Yu. B.; M. Johansson; Rasmussen, K.Ø.

    1999-01-01

    Two models for energy and charge transport and storage in biomolecules are considered. A model based on the discrete nonlinear Schrodinger equation with long-range dispersive interactions (LRI's) between base pairs of DNA is offered for the description of nonlinear dynamics of the DNA molecule. We show that LRI's are responsible for the existence of an interval of bistability where two stable stationary states, a narrow, pinned state and a broad, mobile state, coexist at each value of the tot...

  13. Applications of polymers for biomolecule immobilization in electrochemical biosensors

    International Nuclear Information System (INIS)

    Polymers are becoming inseparable from biomolecule immobilization strategies and biosensor platforms. Their original role as electrical insulators has been progressively substituted by their electrical conductive abilities, which opens a new and broad scope of applications. In addition, recent advances in diagnostic chips and microfluidic systems, together with the requirements of mass-production technologies, have raised the need to replace glass by polymeric materials, which are more suitable for production through simple manufacturing processes. Conducting polymers (CPs), in particular, are especially amenable for electrochemical biosensor development for providing biomolecule immobilization and for rapid electron transfer. It is expected that the combination of known polymer substrates, but also new transducing and biocompatible interfaces, with nanobiotechnological structures, like nanoparticles, carbon nanotubes (CNTs) and nanoengineered 'smart' polymers, may generate composites with new and interesting properties, providing higher sensitivity and stability of the immobilized molecules, thus constituting the basis for new and improved analytical devices for biomedical and other applications. This review covers the state-of-the-art and main novelties about the use of polymers for immobilization of biomolecules in electrochemical biosensor platforms

  14. Biomolecule-assisted route to prepare titania mesoporous hollow structures.

    Science.gov (United States)

    Ding, Shangjun; Wang, Yaoming; Hong, Zhanglian; Lü, Xujie; Wan, Dongyun; Huang, Fuqiang

    2011-10-01

    Amino acids, as a particularly important type of biomolecules, have been used as multifunctional templates to intelligently construct mesoporous TiO(2) hollow structures through a simple solvothermal reaction. The structure-directing behaviors of various amino acids were systematically investigated, and it was found that these biomolecules possess the general capability to assist mesoporous TiO(2) hollow-sphere formation. At the same time, the nanostructures of the obtained TiO(2) are highly dependent on the isoelectric points (pI) of amino acids. Their molecular-structure variations can lead to pI differences and significantly influence the final TiO(2) morphologies. Higher-pI amino acids (e.g., L-lysine and L-arginine) have better structure-directing abilities to generate nanosheet-assembled hollow spheres and yolk/shell structures. The specific morphologies and mesopore size of these novel hollow structures can also be tuned by adjusting the titanium precursor concentration. Heat treatment in air and vacuum was further conducted to transform the as-prepared structures to porous nanoparticle-assembled hollow TiO(2) and TiO(2)/carbon nanocomposites, which may be potentially applied in the fields of photocatalysts, dye-sensitized solar cells, and Li batteries. This study provides some enlightenment on the design of novel templates by taking advantage of biomolecules. PMID:21882272

  15. Repulsive effects of hydrophobic diamond thin films on biomolecule detection

    Energy Technology Data Exchange (ETDEWEB)

    Ruslinda, A. Rahim, E-mail: ruslindarahim@gmail.com [Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Jln Kgr-Alor Setar, Seriab, 01000 Kangar, Perlis (Malaysia); Department of Nano Science and Nano Engineering, School of Advance Science and Engineering, Ohkubo 3-4-1, Shinjuku, 169-8555 Tokyo (Japan); Ishiyama, Y. [Department of Nano Science and Nano Engineering, School of Advance Science and Engineering, Ohkubo 3-4-1, Shinjuku, 169-8555 Tokyo (Japan); Penmatsa, V. [Department of Mechanical and Materials Engineering, Florida International University, 10555 West Flagler Street, Miami, FL 33174 (United States); Ibori, S.; Kawarada, H. [Department of Nano Science and Nano Engineering, School of Advance Science and Engineering, Ohkubo 3-4-1, Shinjuku, 169-8555 Tokyo (Japan)

    2015-02-15

    Highlights: • We report the effect of fluorine plasma treatment on diamond thin film to resist the nonspecific adsorption of biomolecules. • The diamond thin film were highly hydrophobic with a surface energy value of ∼25 mN/m. • The repulsive effect shows excellent binding efficiency for both DNA and HIV-1 Tat protein. - Abstract: The repulsive effect of hydrophobic diamond thin film on biomolecule detection, such as single-nucleotide polymorphisms and human immunodeficiency virus type 1 trans-activator of transcription peptide protein detection, was investigated using a mixture of a fluorine-, amine-, and hydrogen-terminated diamond surfaces. These chemical modifications lead to the formation of a surface that effectively resists the nonspecific adsorption of proteins and other biomolecules. The effect of fluorine plasma treatment on elemental composition was also investigated via X-ray photoelectron spectroscopy (XPS). XPS results revealed a fluorocarbon layer on the diamond thin films. The contact angle measurement results indicated that the fluorine-treated diamond thin films were highly hydrophobic with a surface energy value of ∼25 mN/m.

  16. Repulsive effects of hydrophobic diamond thin films on biomolecule detection

    International Nuclear Information System (INIS)

    Highlights: • We report the effect of fluorine plasma treatment on diamond thin film to resist the nonspecific adsorption of biomolecules. • The diamond thin film were highly hydrophobic with a surface energy value of ∼25 mN/m. • The repulsive effect shows excellent binding efficiency for both DNA and HIV-1 Tat protein. - Abstract: The repulsive effect of hydrophobic diamond thin film on biomolecule detection, such as single-nucleotide polymorphisms and human immunodeficiency virus type 1 trans-activator of transcription peptide protein detection, was investigated using a mixture of a fluorine-, amine-, and hydrogen-terminated diamond surfaces. These chemical modifications lead to the formation of a surface that effectively resists the nonspecific adsorption of proteins and other biomolecules. The effect of fluorine plasma treatment on elemental composition was also investigated via X-ray photoelectron spectroscopy (XPS). XPS results revealed a fluorocarbon layer on the diamond thin films. The contact angle measurement results indicated that the fluorine-treated diamond thin films were highly hydrophobic with a surface energy value of ∼25 mN/m

  17. Arthur Ramos: intelectual em perspectiva

    Directory of Open Access Journals (Sweden)

    Adir da Luz Almeida

    2016-03-01

    Full Text Available O trabalho constituise em resultado de pesquisa sobre o intelectual Arthur Ramos, suas reflexões teóricas e os efeitos no campo social e educativo. Arthur Ramos, intelectual complexo, multifacetado, refletiu sobre várias temáticas, pensando o Brasil como "nação" moderna, como outros intelectuais na passagem do século XIX para o século XX. Através redes de sociabilidade das quais participou e dos cargos públicos que ocupou, incluindo a chefia do Serviço de Ortofrenia e Higiene Mental do Instituto de Pesquisas Educacionais, na administração de Anísio Teixeira como Diretor de Instrução Pública, Rio de Janeiro, na década de 1930. Implanta o Serviço que tem como base a proximidade entre família, escola e comunidade, tendo como perspectiva alcançar as famílias e população pela escola. O foco é a discussão conceitual de "higiene" e "miscigenação", com atenção ao intelectual nesse debate, suas concepções, inflexões e contradições. São utilizadas como fontes algumas obras produzidas por Ramos, e arquivos sobre o SHOM, sob aguarda da Biblioteca Nacional.Palavras chave: intelectual, educação, historiografia, antropologia__________________Abstract: The work is the result of research on the intellectual Arthur Ramos, their theoretical reflections and the effects on social and educational field. Arthur Ramos, complex, multifaceted intellectual, reflected on several themes, thinking the Brazil as modern "nation", like other intellectuals in the passage from the XIX century to the XX century. Through social networks of which participated and the public office he held, including the leadership of the Ortofrenia Service and Mental Hygiene, of the Educational Research Institute, administration of Anísio Teixeira, as Director of Public Instruction, Rio de Janeiro, in the decade of 1930. Deploys the service that is based on the close the proximity between family, school and community, with the prospect to reach the families and

  18. Quantum Simulations of Solvated Biomolecules Using Hybrid Methods

    Science.gov (United States)

    Hodak, Miroslav

    2009-03-01

    One of the most important challenges in quantum simulations on biomolecules is efficient and accurate inclusion of the solvent, because the solvent atoms usually outnumber those in the biomolecule of interest. We have developed a hybrid method that allows for explicit quantum-mechanical treatment of the solvent at low computational cost. In this method, Kohn-Sham (KS) density functional theory (DFT) is combined with an orbital-free (OF) DFT. Kohn-Sham (KS) DFT is used to describe the biomolecule and its first solvation shells, while the orbital-free (OF) DFT is employed for the rest of the solvent. The OF part is fully O(N) and capable of handling 10^5 solvent molecules on current parallel supercomputers, while taking only ˜ 10 % of the total time. The compatibility between the KS and OF DFT methods enables seamless integration between the two. In particular, the flow of solvent molecules across the KS/OF interface is allowed and the total energy is conserved. As the first large-scale applications, the hybrid method has been used to investigate the binding of copper ions to proteins involved in prion (PrP) and Parkinson's diseases. Our results for the PrP, which causes mad cow disease when misfolded, resolve a contradiction found in experiments, in which a stronger binding mode is replaced by a weaker one when concentration of copper ions is increased, and show how it can act as a copper buffer. Furthermore, incorporation of copper stabilizes the structure of the full-length PrP, suggesting its protective role in prion diseases. For alpha-synuclein, a Parkinson's disease (PD) protein, we show that Cu binding modifies the protein structurally, making it more susceptible to misfolding -- an initial step in the onset of PD. In collaboration with W. Lu, F. Rose and J. Bernholc.

  19. CT assessment of blunt diaphragmatic injuries. A retrospective study on 35 cases; Sensibilita' diagnostica della Tomografia Computerizzata nei traumi chiusi del diaframma. Studio retrospettivo di 35 casi consecutivi

    Energy Technology Data Exchange (ETDEWEB)

    Scaglione, M.; Pinto, F.; Giovine, S.; Sacco, M.; Romano, L. [Neaples Univ., Neaples (Italy). Dipt. di Diagnostica per Immagini; Forner, A.L. [Azienda Ospedaliera di Rilievo Nazionale A. Cardarelli, Neaples (Italy). Chirurgia d' Urgenza; Grassi, R.; Romano, S. [Neaples Univ. Federico 2, Neaples (Italy). Ist. di Radiologia, Facolta' di Medicina

    2000-02-01

    Purpose of this work is to evaluate the effectiveness and role of CT in blunt diaphragmatic injuries by reviewing our 8-year experience. It is reviewed the preoperative CT findings of 35 patients with surgically confirmed diaphragmatic rupture. Surgical repair was performed in the acute setting (within 12 hours of trauma) in 22 cases, and late (8 months-5 years) in 13 cases. Twenty-eight patients (80%) were examined with conventional CT and 7 (20%) with Helical CT. Of the 13 patients examined long after trauma, the left hemi diaphragm was ruptured in 12 cases (with visceral herniation in 4), and the right hemi diaphragm in 1, with no herniation. The diaphragmatic rent was found in the dome (15 cases, 43%), muscolotendinous junction (11 cases, 31%), muscular portion (8 cases, 23%), and at the muscular attachments on the ribs (1 case, 3%). As for the site of diaphragmatic injury, CT never depicted the diaphragmatic rent in the dome and at the muscolotendinous junction (74%), not even with thin slices and the multiplanar Helical technique. CT detected indirect signs of injury at the muscular portion (23%), showing the injury site directly in the case with diaphragmatic avulsion (3%). CT is a reliable tool in the diagnosis of suspected diaphragmatic injury in the acute trauma setting. Long after trauma, CT performs poorly because it depicts the diaphragmatic rent only in some peripheral traumas. Helical CT has greater diagnostic potentials, but the injury site and type do affect its capabilities. [Italian] Questo lavoro si propone di valutare la sensibilita' diagnostica e il ruolo della TC nei traumi chiusi del diaframma sulla base dell'analisi retrospettiva degli ultimi 8 anni. Sono state riesaminate le indagini TC preoperatorie di 35 pazienti traumatizzati consecutivi con rottura del diaframma chirurgicamente accertata. In 22 casi la riparazione del diaframma e' avvenuta entro 12 ore dal trauma (fase acuta), in 13 nel lasso di tempo compreso tra 9 mesi

  20. Linkage of biomolecules to solid phases for immunoassay

    International Nuclear Information System (INIS)

    Topics covered by this lecture include a brief review of the principal methods of linkage of biomolecules to solid phase matrices. Copies of the key self explanatory slides are presented as figures together with reprints of two publications by the author dealing with a preferred chemistry for the covalent linkage of antibodies to hydroxyl and amino functional groups and the effects of changes in solid phase matrix and antibody coupling chemistry on the performance of a typical excess reagent immunoassay for thyroid stimulating hormone

  1. Simple approach to study biomolecule adsorption in polymeric microfluidic channels

    International Nuclear Information System (INIS)

    Highlights: ► A simple tool to assess biomolecule adsorption onto the surfaces of microchannels. ► Development for dilution by surface-adsorption based depletion of protein samples. ► It can easily be done using a readily available apparatus like a spin-coater. ► The assessment tool is facile and quantitative. ► Straightforward comparison of different surface chemistries. - Abstract: Herein a simple analytical method is presented for the characterization of biomolecule adsorption on cyclo olefin polymer (COP, trade name: Zeonor®) substrates which are widely used in microfluidic lab-on-a-chip devices. These Zeonor® substrates do not possess native functional groups for specific reactions with biomolecules. Therefore, depending on the application, such substrates must be functionalized by surface chemistry methods to either enhance or suppress biomolecular adsorption. This work demonstrates a microfluidic method for evaluating the adsorption of antibodies and oligonucleotides surfaces. The method uses centrifugal microfluidic flow-through chips and can easily be implemented using common equipment such as a spin coater. The working principle is very simple. The user adds 40 L of the solution containing the sample to the starting side of a microfluidic channel, where it is moved through by centrifugal force. Some molecules are adsorbed in the channel. The sample is then collected at the other end in a small reservoir and the biomolecule concentration is measured. As a pilot application, we characterized the adsorption of goat anti-human IgG and a 20-mer DNA on Zeonor®, and on three types of functionalized Zeonor: 3-aminopropyltriethoxysilane (APTES) modified surface with mainly positive charge, negatively charged surface with immobilized bovine serum albumin (BSA), and neutral, hydrogel-like film with polyethylene glycol (PEG) characteristics. This simple analytical approach adds to the fundamental understanding of the interaction forces in real

  2. Synthesis of fullerenic nanocapsules from bio-molecule carbonisation

    Science.gov (United States)

    Tsang, Shik Chi; Qiu, Jieshan; Harris, Peter J. F.; Fu, Qi Jia; Zhang, Ning

    2000-06-01

    There has been great interest in the incorporation of foreign materials into fullerene structures (C 60, nanotubes, nanoparticles, onions). This interest has been driven by the potential applications of the filled fullerenes, which lie in areas as diverse as optical, electronic, magnetic recording materials and nuclear medicine. In particular, the onion structures of extreme strength may offer excellent protection to their encapsulated nanomaterials for applications. Here, we describe controlled carbonisation of an iron-containing biomolecule, ferritin, at elevated temperatures. This simple technique produces macroscopic quantities of quasi-spherical fullerenic shells (onions) that encapsulate iron nanoparticles of a very narrow range of particle diameters.

  3. Low-energy electron scattering from molecules, biomolecules and surfaces

    CERN Document Server

    Carsky, Petr

    2011-01-01

    Since the turn of the 21st century, the field of electron molecule collisions has undergone a renaissance. The importance of such collisions in applications from radiation chemistry to astrochemistry has flowered, and their role in industrial processes such as plasma technology and lighting are vital to the advancement of next generation devices. Furthermore, the development of the scanning tunneling microscope highlights the role of such collisions in the condensed phase, in surface processing, and in the development of nanotechnology.Low-Energy Electron Scattering from Molecules, Biomolecule

  4. Novel in Vitro Efficiency of Chitosan Biomolecule Against Trichomonas Gallinae

    Directory of Open Access Journals (Sweden)

    SH Pourseyed

    2012-02-01

    Full Text Available Background: Development of new natural agents for parasitic diseases treatment has unexpectedly increased to overcome effectively against emergence and re-emergence of parasitic diseases, the appearance of drug resistant organisms and toxic side effects of current agents. The aim of the study was to evaluate antiprotozoal activities of chitosan biomolecule on trophozoites of Trichomonas gallinae.Methods: The antitrichomonal activity of various low molecular weight chitosan concentrations including 125, 250, 500 and 1250 μg ml-1 against T. gallinae trophozoites cultured in trypticase-yeast extract-maltose medium supplemented with heat-inactivated cold horse serum was evaluated in vitro. Samples containing medium without chitosan were also assayed as controls.Results: The mortality rates at 0, 3 and 6 h post treatment with all concentrations were significantly different from control group (P<0.05. Treated trophozoites showed more susceptibility to the highest concentration reaching mortality rate of 100% at 3h post inoculation. However, at this time, results for 125, 250 and 500 μg ml-1 were 93%, 95% and 96.7%, respectively.Conclusion: The results demonstrate that the application of chitosan biomolecule is a promising option for treatment of trichomoniasis in pigeons.

  5. Biosurfactants: Multifunctional Biomolecules of the 21st Century

    Directory of Open Access Journals (Sweden)

    Danyelle Khadydja F. Santos

    2016-03-01

    Full Text Available In the era of global industrialisation, the exploration of natural resources has served as a source of experimentation for science and advanced technologies, giving rise to the manufacturing of products with high aggregate value in the world market, such as biosurfactants. Biosurfactants are amphiphilic microbial molecules with hydrophilic and hydrophobic moieties that partition at liquid/liquid, liquid/gas or liquid/solid interfaces. Such characteristics allow these biomolecules to play a key role in emulsification, foam formation, detergency and dispersal, which are desirable qualities in different industries. Biosurfactant production is considered one of the key technologies for development in the 21st century. Besides exerting a strong positive impact on the main global problems, biosurfactant production has considerable importance to the implantation of sustainable industrial processes, such as the use of renewable resources and “green” products. Biodegradability and low toxicity have led to the intensification of scientific studies on a wide range of industrial applications for biosurfactants in the field of bioremediation as well as the petroleum, food processing, health, chemical, agricultural and cosmetic industries. In this paper, we offer an extensive review regarding knowledge accumulated over the years and advances achieved in the incorporation of biomolecules in different industries.

  6. Immobilization of Biomolecules on Poly(vinyldimethylazlactone)-containing Surface Scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Barrninger, Joshua [Clemson University; Messman, Jamie M [ORNL; Banaszak, Abigail [Clemson University; Meyer III, Harry M [ORNL; Kilbey, II, S Michael [ORNL

    2009-01-01

    We describe the successful development of a procedure for the step-by-step formation of a reactive, multi-layer polymer scaffold incorporating polymers based on 2-vinyl-4,4-dimethylazlactone (VDMA) on a silicon wafer and the characterization of these materials. Also discussed is the development of a procedure for the non-site specific attachment of a biomolecule to the modified silicon wafer, including scaffolds modified via drop-on-demand (DOD) inkjet printing. VDMA-based polymers were used because of their hydrolytic stability and ability of the pendant azlactone rings to form stable covalent bonds with primary amines without byproducts via nucleophilic addition. This reaction proceeds without a catalyst and at room temperature, yielding a stable amide linkage, which adds to the ease of construction expected when using VDMA-based polymers. DOD inkjet printing was explored as an interesting method for creating surfaces with one or more patterns of biomolecules, because of the flexibility and ease in pattern design.

  7. Biosurfactants: Multifunctional Biomolecules of the 21st Century

    Science.gov (United States)

    Santos, Danyelle Khadydja F.; Rufino, Raquel D.; Luna, Juliana M.; Santos, Valdemir A.; Sarubbo, Leonie A.

    2016-01-01

    In the era of global industrialisation, the exploration of natural resources has served as a source of experimentation for science and advanced technologies, giving rise to the manufacturing of products with high aggregate value in the world market, such as biosurfactants. Biosurfactants are amphiphilic microbial molecules with hydrophilic and hydrophobic moieties that partition at liquid/liquid, liquid/gas or liquid/solid interfaces. Such characteristics allow these biomolecules to play a key role in emulsification, foam formation, detergency and dispersal, which are desirable qualities in different industries. Biosurfactant production is considered one of the key technologies for development in the 21st century. Besides exerting a strong positive impact on the main global problems, biosurfactant production has considerable importance to the implantation of sustainable industrial processes, such as the use of renewable resources and “green” products. Biodegradability and low toxicity have led to the intensification of scientific studies on a wide range of industrial applications for biosurfactants in the field of bioremediation as well as the petroleum, food processing, health, chemical, agricultural and cosmetic industries. In this paper, we offer an extensive review regarding knowledge accumulated over the years and advances achieved in the incorporation of biomolecules in different industries. PMID:26999123

  8. Biosurfactants: Multifunctional Biomolecules of the 21st Century.

    Science.gov (United States)

    Santos, Danyelle Khadydja F; Rufino, Raquel D; Luna, Juliana M; Santos, Valdemir A; Sarubbo, Leonie A

    2016-01-01

    In the era of global industrialisation, the exploration of natural resources has served as a source of experimentation for science and advanced technologies, giving rise to the manufacturing of products with high aggregate value in the world market, such as biosurfactants. Biosurfactants are amphiphilic microbial molecules with hydrophilic and hydrophobic moieties that partition at liquid/liquid, liquid/gas or liquid/solid interfaces. Such characteristics allow these biomolecules to play a key role in emulsification, foam formation, detergency and dispersal, which are desirable qualities in different industries. Biosurfactant production is considered one of the key technologies for development in the 21st century. Besides exerting a strong positive impact on the main global problems, biosurfactant production has considerable importance to the implantation of sustainable industrial processes, such as the use of renewable resources and "green" products. Biodegradability and low toxicity have led to the intensification of scientific studies on a wide range of industrial applications for biosurfactants in the field of bioremediation as well as the petroleum, food processing, health, chemical, agricultural and cosmetic industries. In this paper, we offer an extensive review regarding knowledge accumulated over the years and advances achieved in the incorporation of biomolecules in different industries. PMID:26999123

  9. Transitioning Streaming to Trapping in DC Insulator-based Dielectrophoresis for Biomolecules

    OpenAIRE

    Camacho-Alanis, Fernanda; Gan, Lin; Ros, Alexandra

    2012-01-01

    Exploiting dielectrophoresis (DEP) to concentrate and separate biomolecules has recently shown large potential as a microscale bioanalytical tool. Such efforts however require tailored devices and knowledge of all interplaying transport mechanisms competing with dielectrophoresis (DEP). Specifically, a strong DEP contribution to the overall transport mechanism is necessary to exploit DEP of biomolecules for analytical applications such as separation and fractionation. Here, we present improve...

  10. Laser desorption mass spectrometry for biomolecule detection and its applications

    International Nuclear Information System (INIS)

    During the past few years, we developed and used laser desorption mass spectrometry for biomolecule detections. Matrix-assisted laser desorption/ionization (MALDI) was successfully used to detect DNA fragments with the size larger than 3000 base pairs. It was also successfully used to sequence DNA with both enzymatic and chemical degradation methods to produce DNA ladders. We also developed MALDI with fragmentation for direct DNA sequencing for short DNA probes. Since laser desorption mass spectrometry for DNA detection has the advantages of fast speed and no need of labeling, it has a great potential for molecular diagnosis for disease and person identification by DNA fingerprinting. We applied laser desorption mass spectrometry to succeed in the diagnosis of cystic fibrosis and several other nerve degenerative diseases such as Huntington's disease. We also succeeded in demonstrating DNA typing for forensic applications

  11. Synthesis of selenium nanorods with assistance of biomolecule

    Indian Academy of Sciences (India)

    S Kannan; K Mohanraj; K Prabhu; S Barathan; G Sivakumar

    2014-12-01

    Nanorods of one-dimensional (1D) trigonal selenium (t-Se) are synthesized using biomolecule substances for five different aging times (1 h, 2 h, 3 h, 1 day and 4 days) by precipitation method. XRD analysis indicates a shift of the (1 0 1) plane towards higher diffraction angle for 1 day aging time. It is observed that the crystallite size decreases with increase in aging time except for an aging period of 4 days. FTIR analysis confirmed that the presence of stretching and bending vibrations of Se–O in both synthesized and commercial selenium samples at 465, 668 and 1118 cm-1. The FESEM micrographs are evident for the changes of rod size as a function of aging time. It is observed that the optical band gap energy is increased with aging time up to 1 day, whereas it decreases in 4 days aging time.

  12. Vacuum foam drying: An alternative to lyophilization for biomolecule preservation

    Directory of Open Access Journals (Sweden)

    R D Jangle

    2012-01-01

    Full Text Available Vacuum foam drying is evaluated as an alternative for lyophilization for enhanced process and storage stability of bovine serum albumin. The protein protective efficiency of different stabilizers was compared in vacuum foam drying and lyophilization. Sucrose mixtures produced better foam characters than mannitol. Unlike calcium lactate, incorporation of polyvinyl pyrrolidone to sucrose synergistically enhanced the recovery of bovine serum albumin. The conformational stability and bovine serum albumin content further increased with sodium phosphate as compared to potassium phosphate. All sucrose mixtures, except calcium lactate showed large α-helix amide-I band at approximately 1656 cm -1 . The amorphous powder diffraction in case of sodium phosphate monobasic mixture retained maximum bovine serum albumin content. The crystallization of similar mixtures in lyophilization reduced its bovine serum albumin content. Vacuum foam drying showed better processing and storage stability of bovine serum albumin than lyophilization process. Hence vacuum foam drying is short, simple and industrially economical process for biomolecules preservation.

  13. Interfacial water thickness at inorganic nanoconstructs and biomolecules: Size matters

    Science.gov (United States)

    Cardellini, Annalisa; Fasano, Matteo; Chiavazzo, Eliodoro; Asinari, Pietro

    2016-04-01

    Water molecules in the proximity of solid nanostructures influence both the overall properties of liquid and the structure and functionality of solid particles. The study of water dynamics at solid-liquid interfaces has strong implications in energy, environmental and biomedical fields. This article focuses on the hydration layer properties in the proximity of Carbon Nanotubes (CNTs) and biomolecules (proteins, polypeptides and amino acids). Here we show a quantitative relation between the solid surface extension and the characteristic length of water nanolayer (δ), which is confined at solid-liquid interfaces. Specifically, the size dependence is attributed to the limited superposition of nonbonded interactions in case of small molecules. These results may facilitate the design of novel energy or biomedical colloidal nanosuspensions, and a more fundamental understanding of biomolecular processes influenced by nanoscale water dynamics.

  14. Biomolecule Profiles in Inedible Wild Mushrooms with Antioxidant Value

    Directory of Open Access Journals (Sweden)

    Isabel C.F.R. Ferreira

    2011-05-01

    Full Text Available The use of natural products isolated from mushrooms, included inedible species, against infection, cancer diseases and other oxidative-stress related diseases is one of the cornerstones of modern medicine. In the present work, the antioxidant molecule profiles of inedible mushroom species were evaluated and compared with those of edible species. The order of antioxidant abundance found in inedible wild mushrooms was: phenolics > flavonoids > ascorbic acid > tocopherols > carotenoids, similar to that of edible species. Furthermore the same energetic biomolecules were found including the disaccharide trehalose, the monosaccharide alcohol derivative mannitol and the fatty acids palmitic, oleic and linoleic acids. Fomitopsis pinicola revealed a very high phenolics concentration (388 mg GAE/g extract and powerful antioxidant properties, mainly reducing power (EC50 value 60 μg/mL similar to the standard Trolox®. It could find applications in the prevention of free radical-related diseases as a source of bioactive compounds.

  15. Platinum(II) complexes as spectroscopic probes for biomolecules

    Energy Technology Data Exchange (ETDEWEB)

    Ratilla, E.

    1990-09-21

    The use of platinum(II) complexes as tags and probes for biomolecules is indeed advantageous for their reactivities can be selective for certain purposes through an interplay of mild reaction conditions and of the ligands bound to the platinum. The use of {sup 195}Pt NMR as a method of detecting platinum and its interactions with biomolecules was carried out with the simplest model of platinum(II) tagging to proteins. Variable-temperature {sup 195}Pt NMR spectroscopy proved useful in studying the stereodynamics of complex thioethers like methionine. The complex, Pt(trpy)Cl{sup +}, with its chromophore has a greater potential for probing proteins. It is a noninvasive and selective tag for histidine and cysteine residues on the surface of cytochrome c at pH 5. The protein derivatives obtained are separable, and the tags are easily quantitated and differentiated through the metal-to-ligand charge transfer bands which are sensitive to the environment of the tag. Increasing the pH to 7.0 led to the modification by Pt(trpy)Cl{sup +}of Arg 91 in cytochrome c. Further studies with guanidine-containing ligands as models for arginine modification by Pt(trpy)Cl{sup +} showed that guanidine can act as a terminal ligand and as a bridging ligand. Owing to the potential utility of Pt(trpy)L{sup n+} as electron dense probes of nucleic acid structure, interactions of this bis-Pt(trpy){sup 2+} complex with nucleic acids was evaluated. Indeed, the complex interacts non-covalently with nucleic acids. Its interactions with DNA are not exactly the same as those of its precedents. Most striking is its ability to form highly immobile bands of DNA upon gel electrophoresis. 232 refs.

  16. Recent Advances in Protein Extraction and Chiral Separation of Biomolecules

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Reverse micelles create unique environment in organic media. They are capable of solubilizing hydrophilic biomolecules (e.g., proteins, peptides, amino acids, and DNAs) in their aqueous interior. This feature brings about the practical use of biomaterials in organic media because reverse micelles solubilize them with the intrinsic activity. In this paper, we focus on recent two topics concerning protein extraction and chiral separation of biomolecules using liquid membranes. In the first topic, we present recent attempts to extract proteins from an aqueous solution into isooctane using reverse micelles, and some important operational parameters to achieve an efficient protein transfer are discussed. Furthermore, novel function of reverse micelles as a protein activation medium is introduced. In the reverse micellar phase, denatured proreins were completely reactivated in the reverse micellar solution. The reverse micellar technique is found to be a useful tool not only for protein separation but also for protein refolding. Furthermore, we found that a cyclic ligand carixarene has an extraction ability to set up optimum conditions for protein transfer. In the second topic, we have found that a supported liquid membrane (SLM) encapsulating enzymes shows high enantioselectivity (enantioselective excess value is over 96%) in the transport of racemic pharmaceutical compound ibuprofen. A different experiment also suggests that the α-chymotrypsin-catalyzed reactions droved the enantioselective transport of L-phenylalanine based on the enantioselectivity of the enzyme. The SLM encapsulating the surfactant-enzyme complex enabled the highly enantioselective separation of racemic mixtures. It can be envisioned that arrangement of appropriate enzymes in the SLM system will allow enantioselective separation of various useful organic compounds.

  17. Assembly and actuation of nanomaterials using active biomolecules.

    Energy Technology Data Exchange (ETDEWEB)

    Spoerke, Erik David; Thayer, Gayle Echo; de Boer, Maarten Pieter; Bunker, Bruce Conrad; Liu, Jun; Corwin, Alex David; Gaudioso, Jennifer Marie; Sasaki, Darryl Yoshio; Boal, Andrew Kiskadden; Bachand, George David; Trent, Amanda M.; Bachand, Marlene; Rivera, Susan B.; Koch, Steven John

    2005-11-01

    The formation and functions of living materials and organisms are fundamentally different from those of synthetic materials and devices. Synthetic materials tend to have static structures, and are not capable of adapting to the functional needs of changing environments. In contrast, living systems utilize energy to create, heal, reconfigure, and dismantle materials in a dynamic, non-equilibrium fashion. The overall goal of the project was to organize and reconfigure functional assemblies of nanoparticles using strategies that mimic those found in living systems. Active assembly of nanostructures was studied using active biomolecules to drive the organization and assembly of nanocomposite materials. In this system, kinesin motor proteins and microtubules were used to direct the transport and interactions of nanoparticles at synthetic interfaces. In addition, the kinesin/microtubule transport system was used to actively assemble nanocomposite materials capable of storing significant elastic energy. Novel biophysical measurement tools were also developed for measuring the collective force generated by kinesin motor proteins, which will provide insight on the mechanical constraints of active assembly processes. Responsive reconfiguration of nanostructures was studied in terms of using active biomolecules to mediate the optical properties of quantum dot (QD) arrays through modulation of inter-particle spacing and associated energy transfer interaction. Design rules for kinesin-based transport of a wide range of nanoscale cargo (e.g., nanocrystal quantum dots, micron-sized polymer spheres) were developed. Three-dimensional microtubule organizing centers were assembled in which the polar orientation of the microtubules was controlled by a multi-staged assembly process. Overall, a number of enabling technologies were developed over the course of this project, and will drive the exploitation of energy-driven processes to regulate the assembly, disassembly, and dynamic

  18. Bifunctional chelating agent for the design and development of site specific radiopharmaceuticals and biomolecule conjugation strategy

    Science.gov (United States)

    Katti, Kattesh V.; Prabhu, Kandikere R.; Gali, Hariprasad; Pillarsetty, Nagavara Kishore; Volkert, Wynn A.

    2003-10-21

    There is provided a method of labeling a biomolecule with a transition metal or radiometal in a site specific manner to produce a diagnostic or therapeutic pharmaceutical compound by synthesizing a P.sub.2 N.sub.2 -bifunctional chelating agent intermediate, complexing the intermediate with a radio metal or a transition metal, and covalently linking the resulting metal-complexed bifunctional chelating agent with a biomolecule in a site specific manner. Also provided is a method of synthesizing the --PR.sub.2 containing biomolecules by synthesizing a P.sub.2 N.sub.2 -bifunctional chelating agent intermediate, complexing the intermediate with a radiometal or a transition metal, and covalently linking the resulting radio metal-complexed bifunctional chelating agent with a biomolecule in a site specific manner. There is provided a therapeutic or diagnostic agent comprising a --PR.sub.2 containing biomolecule.

  19. Diferentes perspectivas de evaluar el pensamiento creativo.

    OpenAIRE

    Soto Martínez, Gloria

    2012-01-01

    RESUMENT 150 PALABRAS El objetivo del trabajo, “Diferentes perspectivas de evaluar el pensamiento creativo”, es estudiar la creatividad, utilizando medidas de corte cognitivo (inteligencia sintética), y psicométrico (Tests de Pensamiento Creativo de Torrance y la Prueba de Imaginación Creativa). En la primera parte se hace una análisis de los principales modelos de la creatividad, así como una revisión exhaustiva de las investigaciones hechas con los instrumentos utilizados en nuestro est...

  20. Nuevas perspectivas para entender el emprendimiento empresarial

    OpenAIRE

    Alfonso Rodríguez Ramírez

    2009-01-01

    El propósito de este artículo es construir de manera ecléctica y holística las bases de un marco teórico que describa, analice e interprete el fenómeno del emprendimiento empresarial desde el punto de vista interdisciplinario. Se busca que éste sea el fundamento para responder a la pregunta ¿cómo entender el emprendimiento?, y para construir, a partir de su evolución, diversas perspectivas que enriquezcan su análisis y estudio. De esta manera el emprendimiento es comprendido como un fenómeno ...

  1. Educar para a literacia : perspectivas e desafios

    OpenAIRE

    Azevedo, Fernando José Fraga de, coord.

    2011-01-01

    Comunicação proferida na abertura do "VII Encontro de Educação : Numeracia e Literacia em Educação" Esta conferência aborda as principais perspectivas e desafios com que nos confrontamos quando abordamos o conceito de literacia. Assume-se que a aprendizagem da literacia é um direito da pessoa e que o conceito incorpora, no seu espectro semântico, processos de transformação social e política, muito para além da mera aprendizagem e domínio das técnicas de leitura e de escrita.

  2. Perspectiva temporal futura y ciclo vital

    OpenAIRE

    Díaz Morales, Juan Francisco

    2006-01-01

    El propósito de este estudio es describir qué cambios se producen en la perspectiva temporal futura (PTF) durante el ciclo vital. Para evaluar la PTF a lo largo del ciclo vital se ha utilizado el modelo de Nurmi (1989), que consta de tres componentes: motivación, planificación y evaluación prospectiva. En el estudio participaron cuatro grupos de personas de diferentes edades: 130 adolescentes (15-18 años), 150 estudiantes universitarios (19-28 años), 100 personas de mediana edad (30-59 años) ...

  3. O banco do futuro: perspectivas e desafios

    OpenAIRE

    André Accorsi

    2014-01-01

    Neste artigo, apresentam-se as perspectivas e os desafios dos bancos no futuro. Com o referencial teórico sobre o tema, construiu-se um questionário para identificar o grau de importância atribuído a 20 diferentes questões. Na pesquisa de campo, abarcaram-se 93 bancários dos níveis gerencial e operacional dos principais bancos brasileiros e 9 professores universitários especialistas em mercado financeiro. Os dados coletados foram analisados estatisticamente usando-se o software Statistical Pa...

  4. Epilepsia do lobo temporal: mecanismos e perspectivas

    OpenAIRE

    Maria José da Silva Fernandes

    2013-01-01

    O artigo apresenta uma breve revisão sobre os achados históricos, epidemiológicos, tratamento e perspectivas terapêuticas para as epilepsias, com enfoque na epilepsia do lobo temporal. Apresenta dados obtidos com estudos de proteômica empregando tecido epiléptico e destaca a importância da aplicação desse método na busca de novos alvos terapêuticos.The article presents a brief review of the historical findings, epidemiological, and therapeutic treatment for epilepsy, with a focus on temporal ...

  5. Perspectiva masculina acerca do aborto provocado

    OpenAIRE

    Graciana Alves Duarte; Augusta Thereza de Alvarenga; Maria José M Duarte Osis; Aníbal Faúndes; Ellen Hardy

    2002-01-01

    OBJETIVO: Analisar a perspectiva de homens de uma comunidade universitária que viviam em união legal ou consensual acerca do aborto provocado. MÉTODOS: Estudo descritivo de corte transversal em que se analisaram informações de 361 entrevistados, pertencentes a diferentes categorias de uma universidade. Utilizou-se o teste de qui-quadrado para avaliar a associação das variáveis dependentes com as independentes. RESULTADOS: Dos entrevistados, 53% afirmaram que as mulheres têm direito a interrom...

  6. Perspectivas do papel do design no artesanato

    OpenAIRE

    Ferreira, Ângela Augusta de Sá; Neves, Maria Manuela; Rodrigues, Cristina S.

    2012-01-01

    O aparecimento de novas correntes de design como, por exemplo, o eco-design, o design social e inclusivo ou o slow design, são primordiais ao nível da gestão de recursos, da relação Homem - natureza, das deficiências e limitações humanas e da sustentabilidade do nosso planeta. O presente estudo explora as perspectivas do papel do design no artesanato. Numa abordagem teórica examina conceitos como: design, o papel do designer, as novas correntes de design e o design para a sustentabilidade....

  7. El desarrollo humano: perfiles y perspectivas futuras

    OpenAIRE

    TERESA TORRES SOLÉ; RAFAEL ALLEPUZ CAPDEVILA

    2009-01-01

    El PNUD calcula todos los años el Índice de Desarrollo Humano (IDH). El objetivo de este trabajo es analizar los antecedentes y las perspectivas futuras del desarrollo humano a partir de los datos de este índice durante el periodo 1970-2000. Esto es, comprobar, a partir de los datos pasados, si las diferencias entre el IDH de los países del mundo están aumentando y valorar la tendencia del IDH esperada para los próximos años. En definitiva, se trata de buscar respuesta a la siguiente pregunta...

  8. Grupos vivenciais sob uma perspectiva junguiana

    Directory of Open Access Journals (Sweden)

    Laura Villares de Freitas

    2005-09-01

    Full Text Available Este artigo tece considerações quanto à possibilidade e ao alcance de grupos vivenciais, sob a perspectiva da Psicologia Analítica de Carl G. Jung, em nosso contexto socio-econômico atual. Há uma proposta prática de grupos de construção de máscaras e personagens, e a apresentação e comentários das contribuições de diferentes autores que trazem conceitos junguianos clássicos para a dimensão grupal, consideram de maneira criativa o ritual, do ponto de vista psicológico, e questionam a viabilidade de trabalhos grupais. Numa abordagem mitológica, são considerados Górgona, Dioniso, Ártemis, Eco e Narciso, com destaque à deusa grega Héstia, cujas características são relacionadas a aspectos necessariamente presentes nos grupos vivenciais e à possibilidade de ocorrer uma experiência psicológica. Os grupos vivenciais são considerados favorecedores da perspectiva de alteridade, na medida em que cada participante tem neles a oportunidade de se afirmar e de ser confirmado, isto é, de se expressar e de refletir, num campo interacional fértil.

  9. Si Nanopores Development for External Control of Transport of Biomolecules

    Energy Technology Data Exchange (ETDEWEB)

    Ileri, N; Tringe, J; Letant, S; Palozoglu, A; Stroeve, P; Faller, R

    2008-06-13

    Nazar Ileri has been involved in an independent, multidisciplinary effort to create a new class of molecular sieves for proteins and viruses. Her experimental work has been performed concurrently at two campuses, LLNL and UC Davis, while theoretical components have been largely accomplished at UC Davis. As will be described, the devices she is creating have great potential to improve very significantly the efficiency and selectivity of molecular transport over what is presently available from state-of-the-art membranes. Our biotechnology training program is based on an integrated study of the transport of biomolecules through conically-shaped, nanoporous silicon membranes. The overall objective of this effort is to demonstrate an efficient, highly selective membrane technology that is manufacturable for macroscopic areas and can be employed in sensing, diagnostic and biomedical applications. Our specific aims are to (1) fabricate and characterize the physical characteristics of the membranes, (2) to demonstrate their utility for molecular transport and separation, and (3) to develop models that will facilitate understanding of these devices as well as improved performance of the next generation of devices. We have proposed that the conical pores have superior performance characteristics compared to other porous filters. To study this hypothesis, complementary approaches from different disciplines, such as membrane synthesis, experiment, and molecular simulation need to be combined. This provides an ideal training environment for a future leader in biotechnology. Hence, for this study, Nazar Ileri has started to carry out a full range of experimental and theoretical investigations under our guidance. First, she has begun fabrication of filters with conical/pyramidal pores. She characterized the pores by AFM and SEM, and analyzed the images using wavelets and other mathematical tools. She has also started to conduct biomolecule transport experiments to compare the

  10. Cold atmospheric plasma sterilization: from bacteria to biomolecules

    Science.gov (United States)

    Kong, Michael

    2009-10-01

    Although ionized gases have been known to have biological effects for more than 100 years, their impact on the practice in healthcare service became very significant only recently. Today, plasma-based surgical tools are used for tissue reduction and blood coagulation as surgical procedures. Most significant however is the speed at which low-temperature gas plasmas are finding new applications in medicine and biology, including plasma sterilization, wound healing, and cancer therapies just to name a few. In the terminology of biotechnology, the ``pipeline'' is long and exciting. This presentation reviews the current status of the field with a particular emphasis on plasma inactivation of microorganisms and biomolecules, for which comprehensive scientific evidence has been obtained. Some of the early speculations of biocidal plasma species are now being confirmed through a combination of optical emission spectroscopy, laser-induced fluorescence, mass spectrometry, fluid simulation and biological sensing with mutated bacteria. Similarly, fundamental studies are being performed to examine cell components targeted by gas plasmas, from membrane, through lipid and membrane proteins, to DNA. Scientific challenge is significant, as the usual complexity of plasma dynamics and plasma chemistry is compounded by the added complication that cells are live and constantly evolving. Nevertheless, the current understanding of plasma inactivation currently provides strong momentum for plasma decontamination technologies to be realized in healthcare. We will discuss the issue of protein and tissue contaminations of surgical instruments and how cold atmospheric plasmas may be used to degrade and reduce their surface load. In the context of plasma interaction with biomolecules, we will consider recent data of plasma degradation of adhesion proteins of melanoma cells. These adhesion proteins are important for cancer cell migration and spread. If low-temperature plasmas could be used to

  11. Si Nanopores Development for External Control of Transport of Biomolecules

    International Nuclear Information System (INIS)

    Nazar Ileri has been involved in an independent, multidisciplinary effort to create a new class of molecular sieves for proteins and viruses. Her experimental work has been performed concurrently at two campuses, LLNL and UC Davis, while theoretical components have been largely accomplished at UC Davis. As will be described, the devices she is creating have great potential to improve very significantly the efficiency and selectivity of molecular transport over what is presently available from state-of-the-art membranes. Our biotechnology training program is based on an integrated study of the transport of biomolecules through conically-shaped, nanoporous silicon membranes. The overall objective of this effort is to demonstrate an efficient, highly selective membrane technology that is manufacturable for macroscopic areas and can be employed in sensing, diagnostic and biomedical applications. Our specific aims are to (1) fabricate and characterize the physical characteristics of the membranes, (2) to demonstrate their utility for molecular transport and separation, and (3) to develop models that will facilitate understanding of these devices as well as improved performance of the next generation of devices. We have proposed that the conical pores have superior performance characteristics compared to other porous filters. To study this hypothesis, complementary approaches from different disciplines, such as membrane synthesis, experiment, and molecular simulation need to be combined. This provides an ideal training environment for a future leader in biotechnology. Hence, for this study, Nazar Ileri has started to carry out a full range of experimental and theoretical investigations under our guidance. First, she has begun fabrication of filters with conical/pyramidal pores. She characterized the pores by AFM and SEM, and analyzed the images using wavelets and other mathematical tools. She has also started to conduct biomolecule transport experiments to compare the

  12. 123I and 13I purification for biomolecules labelling

    International Nuclear Information System (INIS)

    The 123I and 131I are iodine radioisotopes widely used in Nuclear Medicine. The radioisotope 123I is used in diagnosis through the SPECT technique and is routinely produced at IPEN in cyclotron through the reaction: '124Xe (p, 2n) '123Cs -> 123Xe -> 123I. The radioisotope 131I is used both in diagnosis and therapy due to its physical characteristics of decay by β- and its γ-ray emissions that are softened with the use of specific collimators for diagnosis. It is routinely produced at IPEN using the nuclear reactor through the indirect reaction: 130Te (n, γ) ->131Te -> 131I, irradiating compounds containing Te. The radiopharmaceuticals prepared with these radioisotopes go through rigorous quality control tests and the chemical purity of the primary radioisotopes 123I and 131I are within the permissible limits currently defined. However, the presence of some chemical contaminants can prejudice the biomolecules labeling (monoclonal antibodies and peptides), that will produce radiopharmaceuticals of first generation to the oncology area. The aim of this work was to obtain a new purification method of these radioisotopes, allowing the labeling of biomolecules and also to established a process control on those radioisotopes. The methodology was separated on 3 steps: Evaluation of '123I e 131I radionuclidic purity using a hyper pure germanium detector, chemical purity using ICP-OES and the retention and elution study of 131I in several absorbers to choose the most appropriate for the purification tests analyzing the behavior of the possible contaminants. The radionuclidic analyses showed the presence of Te and Co on 131I samples and Te, Tc e Co on 123I samples. The chemical purity analyses showed the presence of Al and Mo in 123I, coming from the window material of the target holder and the presence of Al and Te in 131I samples, coming from the target holder and the target, respectively. The retention and elution study selected the most promising adsorber to the

  13. Polyacrylamide medium for the electrophoretic separation of biomolecules

    Science.gov (United States)

    Madabhushi, Ramakrishna S.; Gammon, Stuart A.

    2003-11-11

    A polyacryalmide medium for the electrophoretic separation of biomolecules. The polyacryalmide medium comprises high molecular weight polyacrylamides (PAAm) having a viscosity average molecular weight (M.sub.v) of about 675-725 kDa were synthesized by conventional red-ox polymerization technique. Using this separation medium, capillary electrophoresis of BigDye DNA sequencing standard was performed. A single base resolution of .about.725 bases was achieved in .about.60 minute in a non-covalently coated capillary of 50 .mu.m i.d., 40 cm effective length, and a filed of 160 V/cm at 40.degree. C. The resolution achieved with this formulation to separate DNA under identical conditions is much superior (725 bases vs. 625 bases) and faster (60 min. vs. 75 min.) to the commercially available PAAm, such as supplied by Amersham. The formulation method employed here to synthesize PAAm is straight-forward, simple and does not require cumbersome methods such as emulsion polymerizaiton in order to achieve very high molecular weights. Also, the formulation here does not require separation of PAAm from the reaction mixture prior to reconstituting the polymer to a final concentration. Furthermore, the formulation here is prepared from a single average mol. wt. PAAm as opposed to the mixture of two different average mo. wt. PAAm previously required to achieve high resolution.

  14. Engineered Carbon-Nanomaterial-Based Electrochemical Sensors for Biomolecules.

    Science.gov (United States)

    Tiwari, Jitendra N; Vij, Varun; Kemp, K Christian; Kim, Kwang S

    2016-01-26

    The study of electrochemical behavior of bioactive molecules has become one of the most rapidly developing scientific fields. Biotechnology and biomedical engineering fields have a vested interest in constructing more precise and accurate voltammetric/amperometric biosensors. One rapidly growing area of biosensor design involves incorporation of carbon-based nanomaterials in working electrodes, such as one-dimensional carbon nanotubes, two-dimensional graphene, and graphene oxide. In this review article, we give a brief overview describing the voltammetric techniques and how these techniques are applied in biosensing, as well as the details surrounding important biosensing concepts of sensitivity and limits of detection. Building on these important concepts, we show how the sensitivity and limit of detection can be tuned by including carbon-based nanomaterials in the fabrication of biosensors. The sensing of biomolecules including glucose, dopamine, proteins, enzymes, uric acid, DNA, RNA, and H2O2 traditionally employs enzymes in detection; however, these enzymes denature easily, and as such, enzymeless methods are highly desired. Here we draw an important distinction between enzymeless and enzyme-containing carbon-nanomaterial-based biosensors. The review ends with an outlook of future concepts that can be employed in biosensor fabrication, as well as limitations of already proposed materials and how such sensing can be enhanced. As such, this review can act as a roadmap to guide researchers toward concepts that can be employed in the design of next generation biosensors, while also highlighting the current advancements in the field. PMID:26579616

  15. Hybrid carbon nanomaterials for electrochemical detection of biomolecules

    Science.gov (United States)

    Laurila, Tomi

    2015-09-01

    Electrochemical detection of different biomolecules in vivo is a promising path towards in situ monitoring of human body and its functions. However, there are several major obstacles, such as sensitivity, selectivity and biocompatiblity, which must be tackled in order to achieve reliably and safely operating sensor devices. Here we show that by utilizing hybrid carbon materials as electrodes to detect two types of neurotransmitters, dopamine and glutamate, several advantages over commonly used electrode materials can be achieved. In particular, we will demonstrate here that it is possible to combine the properties of different carbon allotropes to obtain hybrid materials with greatly improved electrochemical performance. Three following examples of the approach are given: (i) diamond-like carbon (DLC) thin film electrodes with different layer thicknesses, (ii) multi-walled carbon nanotubes grown directly on top of DLC and (iii) carbon nanofibres synthesized on top of DLC thin films. Detailed structural and electrochemical characterization is carried out to rationalize the reasons behind the observed behvior. In addition, results from the atomistic simulations are utilized to obtain more information about the properties of the amorphous carbon thin films.

  16. Radiation damage of biomolecules (RADAM) database development: current status

    International Nuclear Information System (INIS)

    Ion beam therapy offers the possibility of excellent dose localization for treatment of malignant tumours, minimizing radiation damage in normal tissue, while maximizing cell killing within the tumour. However, as the underlying dependent physical, chemical and biological processes are too complex to treat them on a purely analytical level, most of our current and future understanding will rely on computer simulations, based on mathematical equations, algorithms and last, but not least, on the available atomic and molecular data. The viability of the simulated output and the success of any computer simulation will be determined by these data, which are treated as the input variables in each computer simulation performed. The radiation research community lacks a complete database for the cross sections of all the different processes involved in ion beam induced damage: ionization and excitation cross sections for ions with liquid water and biological molecules, all the possible electron – medium interactions, dielectric response data, electron attachment to biomolecules etc. In this paper we discuss current progress in the creation of such a database, outline the roadmap of the project and review plans for the exploitation of such a database in future simulations.

  17. Diagnostic and therapeutic perspectives in nuclear medicine: radiolabelled biomolecules

    International Nuclear Information System (INIS)

    From their beginning, the radiopharmaceuticals chemistry has gone to the study of the molecular chemistry. The radiopharmaceuticals are only in their capacity to detect such specific biochemical places as the receivers and the enzymes. With the recent obtaining of the complete structural sequence of the genome, it doesn't fit doubt of the importance that they have acquired the molecular images for the study from the genetic information to the alterations phenotypic in the chemistry of the human body. So, the future of the diagnostic and therapeutic nuclear medicine, practically is based in the study of protein fragments, peptide structures and chains of DNA radiolabelled for the study of the metabolism In vivo. These investigations represent a substantial change in those paradigms of the pharmaceutical development, when using the own organic capacities as source of medications, instead of considering to the organism like a simple assay tube where molecules act, like they are most of the traditional medications. The investigation of new techniques to design complex stable of Tc-99m, Re-188, Lu-177, Y-90 and Dy-166/Ho-l66 with biomolecules that don't alter the specificity and in general the molecular properties of the same ones. it is a topic of world interest in the environment of the radiopharmaceutical chemistry. In this work some achievements and perspectives are presented on those main diagnostic and therapeutic radiopharmaceuticals of third generation. (Author)

  18. Atomic level analysis of biomolecules by the scanning atom probe

    International Nuclear Information System (INIS)

    Utilizing the unique features of the scanning atom probe (SAP) the binding states of the biomolecules, leucine and methionine, are investigated at atomic level. The molecules are mass analyzed by detecting a single atom and/or clustering atoms field evaporated from a specimen surface. Since the field evaporation is a static process, the evaporated clustering atoms are closely related with the binding between atoms forming the molecules. For example, many thiophene radicals are detected when polythiophene is mass analyzed by the SAP. In the present study the specimens are prepared by immersing a micro cotton ball of single walled carbon nanotubes (SWCNT) in the leucine or methionine solution. The mass spectra obtained by analyzing the cotton balls exhibit singly and doubly ionized carbon ions of SWCNT and the characteristic fragments of the molecules, CH3, CHCH3, C4H7, CHNH2 and COOH for leucine and CH3, SCH3, C2H4, C4H7, CHNH2 and COOH for methionine.

  19. Microfluidic Droplet Dehydration for Concentrating Processes in Biomolecules

    Science.gov (United States)

    Anna, Shelley

    2014-03-01

    Droplets in microfluidic devices have proven useful as picoliter reactors for biochemical processing operations such as polymerase chain reaction, protein crystallization, and the study of enzyme kinetics. Although droplets are typically considered to be self-contained, constant volume reactors, there can be significant transport between the dispersed and continuous phases depending on solubility and other factors. In the present talk, we show that water droplets trapped within a microfluidic device for tens of hours slowly dehydrate, concentrating the contents encapsulated within. We use this slow dehydration along with control of the initial droplet composition to influence gellation, crystallization, and phase separation processes. By examining these concentrating processes in many trapped drops at once we gain insight into the stochastic nature of the events. In one example, we show that dehydration rate impacts the probability of forming a specific crystal habit in a crystallizing amino acid. In another example, we phase separate a common aqueous two-phase system within droplets and use the ensuing two phases to separate DNA from an initial mixture. We further influence wetting conditions between the two aqueous polymer phases and the continuous oil, promoting complete de-wetting and physical separation of the polymer phases. Thus, controlled dehydration of droplets allows for concentration, separation, and purification of important biomolecules on a chip.

  20. Investigation of damage mechanism by ionising radiation on biomolecules

    International Nuclear Information System (INIS)

    Occupational radiation hazard is a very controversial subject. Effects from high radiation doses are well known from past experiences. However, hazard from low doses is still a subject that is hotly debated upon until now. The occupational dosimetry used now is based on a macroscopic scale. Lately, microdosimetry is fast gaining recognition as a more superior way of measuring hazard. More importantly, scientists are researching the basic damage mechanism that leads to biological effects by ionising radiation. In this report, a simulation study of the basic damage mechanism is discussed . This simulation is based upon Monte Carlo calculations and using polyuridylic acid (Poly-U) as the DNA model This simulation tries to relate the physics and chemistry of interactions of ionising radiation with biomolecules. The computer codes used in this simulation, OREC and RADLYS were created by Hamm et al. (1983) in Oak Ridge National Laboratory. The biological endpoints in this simulation are the strand break and base release of the DNA, which is the precursor of all biological effects. These results are compared with model studies that had been done experimentally to check the validity of this simulation. The G-values of strand break and base release from this simulation were -2.35 and 2.75 and compared well with results from irradiation experiments by von Sonntag (I 98 7) from Max Plank's Institute, Germany

  1. Quantification of specific bindings of biomolecules by magnetorelaxometry

    Directory of Open Access Journals (Sweden)

    Steinhoff Uwe

    2008-03-01

    Full Text Available Abstract The binding reaction of the biomolecules streptavidin and anti-biotin antibody, both labelled by magnetic nanoparticles (MNP, to biotin coated on agarose beads, was quantified by magnetorelaxometry (MRX. Highly sensitive SQUID-based MRX revealed the immobilization of the MNP caused by the biotin-streptavidin coupling. We found that about 85% of streptavidin-functionalised MNP bound specifically to biotin-agarose beads. On the other hand only 20% of antibiotin-antibody functionalised MNP were specifically bound. Variation of the suspension medium revealed in comparison to phosphate buffer with 0.1% bovine serum albumin a slight change of the binding behaviour in human serum, probably due to the presence of functioning (non heated serum proteins. Furthermore, in human serum an additional non-specific binding occurs, being independent from the serum protein functionality. The presented homogeneous bead based assay is applicable in simple, uncoated vials and it enables the assessment of the binding kinetics in a volume without liquid flow. The estimated association rate constant for the MNP-labelled streptavidin is by about two orders of magnitude smaller than the value reported for free streptavidin. This is probably due to the relatively large size of the magnetic markers which reduces the diffusion of streptavidin. Furthermore, long time non-exponential kinetics were observed and interpreted as agglutination of the agarose beads.

  2. GroPBS: Fast Solver for Implicit Electrostatics of Biomolecules

    Directory of Open Access Journals (Sweden)

    Franziska eBertelshofer

    2015-11-01

    Full Text Available Knowledge about the electrostatic potential on the surface of biomolecules or biomembranes under physiological conditions is an important step in the attempt to characterize the physico-chemical properties of these molecules and in particular also their interactions with each other. Additionally, knowledge about solution electrostatics may guide also the design of molecules with specified properties. However, explicit water models come at a high computational cost, rendering them unsuitable for large design studies or for docking purposes. Implicit models with the water phase treated as a continuum require the numerical solution of the Poisson-Boltzmann Equation (PBE. Here, we present a new flexible program for the numerical solution of the PBE, allowing for different geometries, and the explicit and implicit inclusion of membranes. It involves a discretization of space and the computation of the molecular surface. The PBE is solved using finite differences, the resulting set of equations is solved using a Gauss-Seidel method. It is shown for the example of the sucrose transporter ScrY that the implicit inclusion of a surrounding membrane has a strong effect also on the electrostatics within the pore region and thus need to be carefully considered e.g. in design studies on membrane proteins.

  3. GESTIÓN HUMANA: TENDENCIAS Y PERSPECTIVAS

    Directory of Open Access Journals (Sweden)

    JUAN GUILLERMO SALDARRIAGA RÍOS

    2008-01-01

    Full Text Available En este artículo se hace referencia a las tendencias y las perspectivas de gestión humana que se imponen en el mundo en la actualidad y que, a su manera, pretenden optimizar la administración del personal de la organización y contribuir al desarrollo e incremento de la productividad y la competitividad. Mediante la realización de un Estado del Arte se logran determinar algunas de las tendencias más relevantes en la actualidad y se concluye que, cada vez con mayor fuerza, dichas tendencias se sustentan en discursos que pretenden "rescatar" al ser humano dentro de la organización, lo que no necesariamente se traduce en los procesos de gestión humana que se realizan en las organizaciones nacionales e internacionales.

  4. Role of multimedial diagnosis of breast cancer in women below 36 year of age; Ruolo della diagnostica integrata nella diagnosi del carcinoma mammario nelle donne con eta' inferiore ai 36 anni

    Energy Technology Data Exchange (ETDEWEB)

    Ciacco, Stefano; Brancato, Beniamino [Centro per lo studio della prevenzione oncologica, Firenze (Italy)

    2005-04-01

    .8% e 91.9% e complessivamente del 98.2%. Nei 65 casi esaminati con clinica, ecografia e citologia i tre metodi hanno avuto sensibilit� rispettivamente del 67.6%, 70.7% e 92.3% e complessivamente del 95.3%. Nei 123 casi esaminati con clinica, diagnostica per immagini (ecografia e/o mammografia) e citologia i tre metodi hanno avuto sensibilit� rispettivamente del 76.4%, 78.4% e complessivamente del 96.7%. Se la sensibilit� fosse stata calcolata rispetto all'esame immediatamente precedente la diagnosi, essa sarebbe stata pi� elevata, rispettivamente del 74.4% per l'esame clinico, 76.8% per la mammografia, 73.5% per l'ecografia, 90.9% per la citologia (97.7% se si escludono dalla valutazione i prelievi inadeguati), e complessivamente del 96.1%. La neoplasia � stata sospettata da una sola delle tre metodiche rispettivamente nel 2.4% con l'esame clinico, nel 1.6% con l'imaging e nel 7.3% dei casi con la citologia. Il confronto tra mammografia e ecografia � stato possibile in 58 casi studiati con entrambe le metodiche: la sensibilit� � stata 79.3% per l'ecografia e 74.1% per la mammografia ({chi}2=0.1, p=0.66). Conclusioni: La diagnosi di carcinoma mammario in donne in et� inferiore a 36 anni � difficile, con sensibilit� inferiore alle donne pi� anziane, con l'esclusione della citologia. Integrare pi� metodiche (diagnostica per immagini e citologia) � essenziale per avere un tasso limitato di falsi negativi. In particolare l'impiego esteso della citologia in presenza di dubbio diagnostico anche modico, clinico o strumentale, � molto vantaggioso. L'analisi della sensibilit� si deve basare su un registro indipendente di patologia ed essere riferita ad un determinato periodo di tempo entro il quale un esame negativo viene considerato falso negativo. L'analisi limitata alle indagini immediatamente precedenti la diagnosi comporta una erronea sovrastima della sensibilit�.

  5. Perspectivas de una estrategia nacional de competitividad

    Directory of Open Access Journals (Sweden)

    Roberto Gutiérrez

    1997-06-01

    Full Text Available En los años cincuentas surgió una amplia perspectiva teórica llamada la teoría de la modernización, la cual ha tenido una gran difusión en las ciencias sociales desde entonces. La "modernización" era el camino hacia el desarrollo de un país. La pretendida modernidad incluía una economía liberalizada, un sistema político democrático y una cultura universal. Hoy, la receta para lograr el desarrollo consiste en ser competitivos en los mercados mundiales. Las promesas de la modernización y la competitividad no se han convertido ni se convertirán en realidad. En el presente ensayo hay un examen del devenir histórico de las teorías de la modernización y de las ideas sobre competitividad para resaltar sus similitudes, sus afirmaciones y aquello que está ausente en ambas, y analizar el resultado de sus promesas en relación con el desarrollo nacional. No conocer la historia del descrédito de las teorías sobre la modernización es condenarse a repetirla; mínimo, a reciclarla con unas ideas que son variaciones alrededor del mismo tema. Un análisis de los supuestos, postulados y prescripciones compartidos por las perspectivas que tratan sobre la modernización y la competitividad de nuestras sociedades permite apreciar el alcance de la actual estrategia nacional de competitividad en un país como Colombia.

  6. Synthesis of vaterite and aragonite crystals using biomolecules of tomato and capsicum

    Science.gov (United States)

    Chen, Long; Xu, Wang-Hua; Zhao, Ying-Guo; Kang, Yan; Liu, Shao-Hua; Zhang, Zai-Yong

    2012-12-01

    In this paper, biomimetic synthesis of calcium carbonate (CaCO3) in the presence of biomolecules of two vegetables-tomato and capsicum is investigated. Scanning electron microscopy and X-ray powder diffractometry were used to characterize the CaCO3 obtained. The biomolecules in the extracts of two vegetables are determined by UV-vis or FTIR. The results indicate that a mixture of calcite and vaterite spheres constructed from small particles is produced with the extract of tomato, while aragonite rods or ellipsoids are formed in the presence of extract of capsicum. The possible formation mechanism of the CaCO3 crystals with tomato biomolecules can be interpreted by particle-aggregation based non-classical crystallization laws. The proteins and/or other biomolecules in tomato and capsicum may control the formation of vaterite and aragonite crystals by adsorbing onto facets of them.

  7. Plastic Trash goes Biohybrid"-Rapid and Selective Functionalization of Inert Plastic Surfaces with Biomolecules

    DEFF Research Database (Denmark)

    Schiller, Stefan M; Kambhampati, Dev; Stengel, Gudrun;

    2010-01-01

    The covalent functionalization of "inert" polymers such as polypropylene with biomolecules for biocompatible or biosensor surfaces is challenging. Here we present a powerful approach to covalently modify "inert" macromolecular surfaces with biomacromolecules reusing old plastic material. A special...

  8. Recent advances in exploiting ionic liquids for biomolecules: Solubility, stability and applications.

    Science.gov (United States)

    Sivapragasam, Magaret; Moniruzzaman, Muhammad; Goto, Masahiro

    2016-08-01

    The technological utility of biomolecules (e.g. proteins, enzymes and DNA) can be significantly enhanced by combining them with ionic liquids (ILs) - potentially attractive "green" and "designer" solvents - rather than using in conventional organic solvents or water. In recent years, ILs have been used as solvents, cosolvents, and reagents for biocatalysis, biotransformation, protein preservation and stabilization, DNA solubilization and stabilization, and other biomolecule-based applications. Using ILs can dramatically enhance the structural and chemical stability of proteins, DNA, and enzymes. This article reviews the recent technological developments of ILs in protein-, enzyme-, and DNA-based applications. We discuss the different routes to increase biomolecule stability and activity in ILs, and the design of biomolecule-friendly ILs that can dissolve biomolecules with minimum alteration to their structure. This information will be helpful to design IL-based processes in biotechnology and the biological sciences that can serve as novel and selective processes for enzymatic reactions, protein and DNA stability, and other biomolecule-based applications. PMID:27312484

  9. Effect of membrane hydrophilization on ultrafiltration performance for biomolecules separation

    Energy Technology Data Exchange (ETDEWEB)

    Susanto, H., E-mail: heru.susanto@undip.ac.id [Department of Chemical Engineering, Universitas Diponegoro, Jl. Prof. Sudarto-Tembalang, Semarang (Indonesia); Roihatin, A.; Aryanti, N.; Anggoro, D.D. [Department of Chemical Engineering, Universitas Diponegoro, Jl. Prof. Sudarto-Tembalang, Semarang (Indonesia); Ulbricht, M. [Lehrstuhl fuer Technische Chemie, Universitaet Duisburg-Essen, Germany, Universitaetstr. 5, Essen (Germany)

    2012-10-01

    fouling ultrafiltration (UF) membranes. Black-Right-Pointing-Pointer We characterized the membranes before and after modification. Black-Right-Pointing-Pointer We examined the unmodified and modified membranes for biomolecules filtration. Black-Right-Pointing-Pointer All the modifications changed the membrane characteristics and the membrane performance. Black-Right-Pointing-Pointer All the modifications resulted in UF membranes having higher resistance towards fouling.

  10. Effect of membrane hydrophilization on ultrafiltration performance for biomolecules separation

    International Nuclear Information System (INIS)

    characterized the membranes before and after modification. ► We examined the unmodified and modified membranes for biomolecules filtration. ► All the modifications changed the membrane characteristics and the membrane performance. ► All the modifications resulted in UF membranes having higher resistance towards fouling.

  11. Productividad, trabajo y salud: la perspectiva psicosocial

    Directory of Open Access Journals (Sweden)

    York Iván Puerto Barrios

    2007-07-01

    Full Text Available Con la opción de analizar las condiciones de trabajo en oficina, el texto realiza una sucinta pero precisa revisión de la conceptualización sobre productividad y consumo. Se documenta la relación contradictoria entre bienestar y rendimiento en el trabajo al identificar el riesgo de llevar al límite de sus capacidades la participación del trabajador como factor de productividad, ignorando que éste tiene además el rol de consumidor activo de bienes y servicios para que la producción tenga sentido. Se plantea que exigir al trabajador hasta su agotamiento puede mermar sustancialmente su doble condición de productor y consumidor. Específicamente, se presenta la perspectiva del trabajo en oficinas innovadas conceptual y tecnológicamente, con procesos laborales y patrones de desgaste y morbilidad de"nidos. El tiempo, el ritmo, la parcelación, el control del trabajo y la reestructuración en las organizaciones son, entre otros, factores que convergen para potenciar fenómenos de sobrecarga o subcarga mental con la consecuente aparición de estrés excedente y sus patologías asociadas.

  12. Different size biomolecules anchoring on porous silicon surface: fluorescence and reflectivity pores infiltration comparative studies

    Energy Technology Data Exchange (ETDEWEB)

    Giovannozzi, Andrea M.; Rossi, Andrea M. [National Institute for Metrological Research, Thermodynamic Division, Strada delle Cacce 91, 10135 Torino (Italy); Renacco, Chiara; Farano, Alessandro [Ribes Ricecrhe Srl, Via Lavoratori Vittime del Col du Mont 24, 11100 Aosta (Italy); Derosas, Manuela [Biodiversity Srl, Via Corfu 71, 25124 Brescia (Italy); Enrico, Emanuele [National Institute for Metrological Research, Electromagnetism Division, Strada delle Cacce 91, 10135 Torino (Italy)

    2011-06-15

    The performance of porous silicon optical based biosensors strongly depends on material nanomorphology, on biomolecules distribution inside the pores and on the ability to link sensing species to the pore walls. In this paper we studied the immobilization of biomolecules with different size, such as antibody anti aflatoxin (anti Aflatox Ab, {proportional_to}150 KDa), malate dehydrogenase (MDH, {proportional_to}36KDa) and metallothionein (MT, {proportional_to}6KDa) at different concentrations on mesoporous silicon samples ({proportional_to}15 nm pores diameter). Fluorescence measurements using FITC- labeled biomolecules and refractive index analysis based on reflectivity spectra have been employed together to detect the amount of proteins bound to the surface and to evaluate their diffusion inside the pores. Here we suggest that these two techniques should be used together to have a better understanding of what happens at the porous silicon surface. In fact, when pores dimensions are not perfectly tuned to the protein size a higher fluorescence signal doesn't often correspond to a higher biomolecules distribution inside the pores. When a too much higher concentration of biomolecule is anchored on the surface, steric crowd effects and repulsive interactions probably take over and hinder pores infiltration, inducing a small or absent shift in the fringe pattern even if a higher fluorescence signal is registered. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. Constructing Optimal Coarse-Grained Sites of Huge Biomolecules by Fluctuation Maximization.

    Science.gov (United States)

    Li, Min; Zhang, John Zenghui; Xia, Fei

    2016-04-12

    Coarse-grained (CG) models are valuable tools for the study of functions of large biomolecules on large length and time scales. The definition of CG representations for huge biomolecules is always a formidable challenge. In this work, we propose a new method called fluctuation maximization coarse-graining (FM-CG) to construct the CG sites of biomolecules. The defined residual in FM-CG converges to a maximal value as the number of CG sites increases, allowing an optimal CG model to be rigorously defined on the basis of the maximum. More importantly, we developed a robust algorithm called stepwise local iterative optimization (SLIO) to accelerate the process of coarse-graining large biomolecules. By means of the efficient SLIO algorithm, the computational cost of coarse-graining large biomolecules is reduced to within the time scale of seconds, which is far lower than that of conventional simulated annealing. The coarse-graining of two huge systems, chaperonin GroEL and lengsin, indicates that our new methods can coarse-grain huge biomolecular systems with up to 10 000 residues within the time scale of minutes. The further parametrization of CG sites derived from FM-CG allows us to construct the corresponding CG models for studies of the functions of huge biomolecular systems. PMID:26930392

  14. Room temperature ionic liquids interacting with bio-molecules: an overview of experimental and computational studies

    Science.gov (United States)

    Benedetto, Antonio; Ballone, Pietro

    2016-03-01

    We briefly review experimental and computational studies of room temperature ionic liquids (RTILs) interacting with important classes of biomolecules, including phospholipids, peptides and proteins, nucleic acids and carbohydrates. Most of these studies have been driven by the interest for RTILs applications as solvents. Thus, available experimental data cover primarily thermodynamic properties such as the reciprocal solubility of RTILs and bio-molecules, as well as phase boundaries. Less extensive data are also available on transport properties such as diffusion and viscosity of homogeneous binary (RTILs/biomolecules) and ternary (RTIL/biomolecules/water) solutions. Most of the structural information at the atomistic level, of interest especially for biochemical, pharmaceutical and nanotechnology applications, has been made available by molecular dynamics simulations. Major exceptions to this statement are represented by the results from NMR and circular dichroism spectroscopy, by selected neutron and X-ray scattering data, and by recent neutron reflectometry measurements on lipid bilayers on surfaces, hydrated by water-RTIL solutions. A final section of our paper summarizes new developments in the field of RTILs based on amino acids, that combine in themselves the two main aspects of our discussion, i.e. ionic liquids and bio-molecules.

  15. An aptamer-functionalized chemomechanically modulated biomolecule catch-and-release system

    Science.gov (United States)

    Shastri, Ankita; McGregor, Lynn M.; Liu, Ya; Harris, Valerie; Nan, Hanqing; Mujica, Maritza; Vasquez, Yolanda; Bhattacharya, Amitabh; Ma, Yongting; Aizenberg, Michael; Kuksenok, Olga; Balazs, Anna C.; Aizenberg, Joanna; He, Ximin

    2015-05-01

    The efficient extraction of (bio)molecules from fluid mixtures is vital for applications ranging from target characterization in (bio)chemistry to environmental analysis and biomedical diagnostics. Inspired by biological processes that seamlessly synchronize the capture, transport and release of biomolecules, we designed a robust chemomechanical sorting system capable of the concerted catch and release of target biomolecules from a solution mixture. The hybrid system is composed of target-specific, reversible binding sites attached to microscopic fins embedded in a responsive hydrogel that moves the cargo between two chemically distinct environments. To demonstrate the utility of the system, we focus on the effective separation of thrombin by synchronizing the pH-dependent binding strength of a thrombin-specific aptamer with volume changes of the pH-responsive hydrogel in a biphasic microfluidic regime, and show a non-destructive separation that has a quantitative sorting efficiency, as well as the system's stability and amenability to multiple solution recycling.

  16. Detection of biomolecules and bioconjugates by monitoring rotated grating-coupled surface plasmon resonance

    CERN Document Server

    Szalai, Aniko; Somogyi, Aniko; Szenes, Andras; Banhelyi, Balazs; Csapo, Edit; Dekany, Imre; Csendes, Tibor; Csete, Maria

    2016-01-01

    Plasmonic biosensing chips were prepared by fabricating wavelength-scaled dielectric-metal interfacial gratings on thin polycarbonate films covered bimetal layers via two-beam interference laser lithography. Lysozyme (LYZ) biomolecules and gold nanoparticle (AuNP-LYZ) bioconjugates with 1:5 mass ratio were seeded onto the biochip surfaces. Surface plasmon resonance spectroscopy was performed before and after biomolecule seeding in a modified Kretschmann-arrangement by varying the azimuthal and polar angles to optimize the conditions for rotated grating-coupling. The shift of secondary and primary resonance peaks originating from rotated grating-coupling phenomenon was monitored to detect the biomolecule and bioconjugate adherence. Numerical calculations were performed to reproduce the measured reflectance spectra and the resonance peak shifts caused by different biocoverings. Comparison of measurements and calculations proved that monitoring the narrower secondary peaks under optimal rotated-grating coupling ...

  17. Radical Reactions in the Gas Phase: Recent Development and Application in Biomolecules

    Directory of Open Access Journals (Sweden)

    Yang Gao

    2014-01-01

    Full Text Available This review summarizes recent literature describing the use of gas phase radical reactions for structural characterization of complex biomolecules other than peptides. Specifically, chemical derivatization, in-source chemical reaction, and gas phase ion/ion reactions have been demonstrated as effective ways to generate radical precursor ions that yield structural informative fragments complementary to those from conventional collision-induced dissociation (CID. Radical driven dissociation has been applied to a variety of biomolecules including peptides, nucleic acids, carbohydrates, and phospholipids. The majority of the molecules discussed in this review see limited fragmentation from conventional CID, and the gas phase radical reactions open up completely new dissociation channels for these molecules and therefore yield high fidelity confirmation of the structures of the target molecules. Due to the extensively studied peptide fragmentation, this review focuses only on nonpeptide biomolecules such as nucleic acids, carbohydrates, and phospholipids.

  18. El bienestar subjetivo: Actualidad y perspectivas

    Directory of Open Access Journals (Sweden)

    Guillermo Díaz Llanes

    2001-12-01

    Full Text Available Se realizó una revisión de los trabajos sobre bienestar subjetivo publicados en el mundo en los últimos años y se analizaron críticamente los resultados obtenidos tomando en consideración algunos de los fundamentos epistemológicos que les sirvieron de sustento. La enorme vigencia de los estudios sobre bienestar subjetivo en la actualidad pone de manifiesto la creciente conciencia de los investigadores acerca de la importancia del estudio de los factores que tributan a la salud desde una perspectiva positiva. La comprensión de la compleja madeja de interacciones que determinan el bienestar subjetivo en los niveles macrosocial, microsocial e individual, resulta requisito indispensable para la instrumentación de intervenciones en el nivel primario de atención y así elevar dicho indicador, tan ligado a la salud.A review of the papers on subjective well-being published in the world during the last years was made. The results obtained were critically analyzed taking into account the epistemological foundations that served as a sustenance. The fact that the studies about subjective well-being are still in force shows the increasing awareness of the investigators about the importance of studying those factors influencing positively on health. The understanding of the complex skein of interactions determining the subjective well-being at the macrosocial, microsocial and individual levels is an indispensable requirement for the implementation of interventions at the primary health care level and for elevating this indicator so closely related to health.

  19. O banco do futuro: perspectivas e desafios

    Directory of Open Access Journals (Sweden)

    André Accorsi

    2014-03-01

    Full Text Available Neste artigo, apresentam-se as perspectivas e os desafios dos bancos no futuro. Com o referencial teórico sobre o tema, construiu-se um questionário para identificar o grau de importância atribuído a 20 diferentes questões. Na pesquisa de campo, abarcaram-se 93 bancários dos níveis gerencial e operacional dos principais bancos brasileiros e 9 professores universitários especialistas em mercado financeiro. Os dados coletados foram analisados estatisticamente usando-se o software Statistical Package for the Social Sciences, versão 13.0. Observando-se as principais conclusões da amostra, não há diferença estatística entre os funcionários dos bancos pesquisados, mas o mesmo não ocorreu entre bancários e professores. Algumas variáveis apresentaram maior relevância: combate às fraudes, business intelligence, bancarização e atendimento rápido. A partir da análise fatorial, identificaram-se seis fatores: sustentabilidade e papel do Brasil; mobilidade e segurança; regulação e novas tecnologias; globalização, inserção e privacidade; atendimento inteligente e bancarização. Pela análise discriminante, classificaram-se corretamente 79,3 e 66,7% dos funcionários do Bradesco e do Banco do Brasil, respectivamente, e 78,8% dos gerentes.

  20. Induction of Biomolecules in Mature Leaves of Terminalia arjuna Due to Feeding of Antheraea mylitta Drury

    Directory of Open Access Journals (Sweden)

    G. Abraham

    2004-01-01

    Full Text Available Terminalia arjuna is an important food plant of the tasar silkworm, Antheraea mylitta Drury. In this study, we investigated the induction of biomolecules in mature leaves of these plants subjected to insect feeding. Increase in total tannin content, lipid peroxidation, and trypsin inhibitor activity have been observed in mature leaves damaged by the insects. The growth rate of Vth instar larvae of A. mylitta fed on previously damaged foliage reduced by 87.1%. Induction of biomolecules for defense mechanisms in relation to herbivore damage has been discussed.

  1. A new method for immobilization of biomolecules using preirradiation grafting at low temperature

    International Nuclear Information System (INIS)

    A new method of biomolecule immobilization is described in which a monomer-conjugated enzyme (asparaginase, Asp) is grafted together with free monomer (acrylamide, AAm) onto a cellulose sheet which had been preirradiated in a 60Co source. The preirradiation and grafting steps are carried out in air at - 780C and in vacuum at 00C respectively. The grafting is probably caused by trapped radicals. The immobilized enzyme retains significant activity and is stable to storage. The technique is applicable to immobilization of a wide variety of biomolecules, such as enzymes, antibodies and drugs. The products may be used for therapeutic or diagnostic applications. (author)

  2. Metal Stable Isotope Tagging: Renaissance of Radioimmunoassay for Multiplex and Absolute Quantification of Biomolecules.

    Science.gov (United States)

    Liu, Rui; Zhang, Shixi; Wei, Chao; Xing, Zhi; Zhang, Sichun; Zhang, Xinrong

    2016-05-17

    The unambiguous quantification of biomolecules is of great significance in fundamental biological research as well as practical clinical diagnosis. Due to the lack of a detectable moiety, the direct and highly sensitive quantification of biomolecules is often a "mission impossible". Consequently, tagging strategies to introduce detectable moieties for labeling target biomolecules were invented, which had a long and significant impact on studies of biomolecules in the past decades. For instance, immunoassays have been developed with radioisotope tagging by Yalow and Berson in the late 1950s. The later languishment of this technology can be almost exclusively ascribed to the use of radioactive isotopes, which led to the development of nonradioactive tagging strategy-based assays such as enzyme-linked immunosorbent assay, fluorescent immunoassay, and chemiluminescent and electrochemiluminescent immunoassay. Despite great success, these strategies suffered from drawbacks such as limited spectral window capacity for multiplex detection and inability to provide absolute quantification of biomolecules. After recalling the sequences of tagging strategies, an apparent question is why not use stable isotopes from the start? A reasonable explanation is the lack of reliable means for accurate and precise quantification of stable isotopes at that time. The situation has changed greatly at present, since several atomic mass spectrometric measures for metal stable isotopes have been developed. Among the newly developed techniques, inductively coupled plasma mass spectrometry is an ideal technique to determine metal stable isotope-tagged biomolecules, for its high sensitivity, wide dynamic linear range, and more importantly multiplex and absolute quantification ability. Since the first published report by our group, metal stable isotope tagging has become a revolutionary technique and gained great success in biomolecule quantification. An exciting research highlight in this area

  3. Addressing challenges in preparation of 211At-labeled biomolecules for use in targeted alpha therapy

    International Nuclear Information System (INIS)

    There are significant challenges in the development of 211At-labeled biomolecules for application to targeted alpha therapy. Challenges that we have addressed include development of: (1) labeling methods to obtain high in vivo 211At-label stability, (2) approaches to consistently obtain high recovery yields of Na[211At]At from irradiated bismuth targets, (3) methods to optimize biomolecule labeling yields, (4) reagents for use of 211At in pretargeting approach to cancer therapy, and (5) 211At-labeled antibodies in conditioning for hematopoietic cell transplantation. (author)

  4. Cuidar em enfermagem na perspectiva do género

    OpenAIRE

    Dias, Hélia

    2003-01-01

    Dissertação apresentada com vista à obtenção do grau de Mestre em Sexologia.Orientadora: Professora Doutora Maria Luisa Lima O cuidar representa uma necessidade humana e é reconhecido como o núcleo central da enfermagem. Desenvolve-se uma revisão de literatura sobre o conceito, do ponto de vista teórico e empírico, desde quatro perspectivas: antropológica, filosófica, psicossocial (Patistea, 1999) e ideológica. Esta última inclui uma perspectiva de género, que é recente na ...

  5. La perspectiva de género en profesionales psicoeducativos

    OpenAIRE

    De Angelis, Patricia; Labandal, Livia Garcia

    2011-01-01

    Este trabajo intenta profundizar el análisis de la perspectiva de género en considerando la historización del concepto de género en trayectos de formación de Profesionales Psicoeducativos. Para ello tomamos como recursos de análisis entrevistas a Profesionales Psicoeducativos en ejercicio en relación con la perspectiva de género y experiencias ligadas a la época de la propia formación como formadoras de formadores, para posteriormente avanzar sobre algunos documentos actuales y las posibil...

  6. Sobre los cambios de perspectiva en el conocimiento

    OpenAIRE

    Barreo, Luz Marina

    2008-01-01

    El propósito de este artículo es explorar el significado y los alcances de los cambios de perspectiva que a veces ocurren cuando vemos las cosas desde el punto de vista teórico, al producirse un cambio de paradigma en el conocimiento, o, si las vemos desde el uso práctico de la razón, cuando se produce un cambio en la personalidad o una “conversión”. La mera cuestión sobre la posibilidad de un cambio radical de perspectiva es filosófica en un sentido profundo: sugiere la existencia de un camp...

  7. Perspectiva espiritual de la mujer con cáncer

    OpenAIRE

    Milena Alexandra Galvis-López; Beatriz Pérez-Giraldo

    2011-01-01

    Objetivo: comparar la perspectiva espiritual de las mujeres diagnosticadas con cáncer propio de su género (seno, útero, ovarios) y de las mujeres diagnosticadas con otros tipos de cáncer. Método: diseño cuantitativo de tipo descriptivo comparativo, de corte transversal. Se empleó una encuesta sociodemográfica para caracterizar la población y la Escala de perspectiva espiritual de Pamela Reed, a la cual se le realizó el análisis de confiabilidad que reportó un alfa de Cronbach de 0,799 en el g...

  8. Mujeres inmigrantes : realidades, estereotipos y perspectivas educativas

    Directory of Open Access Journals (Sweden)

    María Dolores Pérez Grande

    2008-01-01

    Full Text Available La perspectiva de género resulta imprescindible en el análisis del fenómeno migratorio en el que las mujeres son cada vez una parte más activa y relevante. Las mujeres aparecen en sus propios discursos como un colectivo enormemente heterogéneo que no se corresponde con los estereotipos de mujer analfabeta, sumisa o victima pasiva de sus circunstancias a la que hay que ayudar a desenvolverse. Por el contrario aparecen en su mayoría como mujeres fuertes, con iniciativa y en muchas ocasiones con estudios superiores y un estatus por encima de la media en sus países de origen, aunque tienen que vivir frecuentemente en España situaciones duras y dolorosas. Las problemáticas y recursos de las mujeres son muy variados y los proyectos de formación o educación no pueden restringirse a la alfabetización, el idioma o la formación laboral en determinadas profesiones consideradas típica y estereotipadamente femeninas, sino que es preciso facilitar la integración en proyectos educativos normalizados, en conjunto con el resto de la población autóctona, impulsando un reconocimiento más eficaz de los conocimientos formales y no formales que traen de sus países de origen.The genre perspective turns out to be indispensable in the analysis of themigratory phenomenon in which women are gradually a more active and relevant part. The women appear in their own speeches as an enormously heterogeneous group that does not correspond with the stereotypes ofilliterate,submissive woman or passive victim oftheir own circumstances who need tobe helped in their development. On the contrary they appear mainly as strong women, with initiative and on many occasions with top studies and a status over the average in their native lands, though they have to live frequently in Spain through hard and painful situations. The problems and resources of these women are very varied and the projects of training or education cannot be restricted to the literacy, the language

  9. Cellular Viscosity in Prokaryotes and Thermal Stability of Low Molecular Weight Biomolecules.

    Science.gov (United States)

    Cuecas, Alba; Cruces, Jorge; Galisteo-López, Juan F; Peng, Xiaojun; Gonzalez, Juan M

    2016-08-23

    Some low molecular weight biomolecules, i.e., NAD(P)H, are unstable at high temperatures. The use of these biomolecules by thermophilic microorganisms has been scarcely analyzed. Herein, NADH stability has been studied at different temperatures and viscosities. NADH decay increased at increasing temperatures. At increasing viscosities, NADH decay rates decreased. Thus, maintaining relatively high cellular viscosity in cells could result in increased stability of low molecular weight biomolecules (i.e., NADH) at high temperatures, unlike what was previously deduced from studies in diluted water solutions. Cellular viscosity was determined using a fluorescent molecular rotor in various prokaryotes covering the range from 10 to 100°C. Some mesophiles showed the capability of changing cellular viscosity depending on growth temperature. Thermophiles and extreme thermophiles presented a relatively high cellular viscosity, suggesting this strategy as a reasonable mechanism to thrive under these high temperatures. Results substantiate the capability of thermophiles and extreme thermophiles (growth range 50-80°C) to stabilize and use generally considered unstable, universal low molecular weight biomolecules. In addition, this study represents a first report, to our knowledge, on cellular viscosity measurements in prokaryotes and it shows the dependency of prokaryotic cellular viscosity on species and growth temperature. PMID:27558730

  10. Nanohybrid structure analysis and biomolecule release behavior of polysaccharide-CDHA drug carriers

    Science.gov (United States)

    Huang, Li-Ying; Liu, Ting-Yu; Liu, Tse-Ying; Mevold, Andreas; Hardiansyah, Andri; Liao, Hung-Chou; Lin, Chin-Ching; Yang, Ming-Chien

    2013-10-01

    Nanoscaled polymer composites were prepared from polysaccharide chitosan (CS) and Ca-deficient hydroxyapatite (CDHA). CS-CDHA nanocomposites were synthesized by in situ precipitation at pH 9, and the CS-CDHA carriers were then fabricated by ionic cross-linking methods using tripolyphosphate and chemical cross-linking methods by glutaraldehyde and genipin. Certain biomolecules such as vitamin B12, cytochrome c, and bovine serum albumin were loaded into the CS-CDHA carriers, and their release behaviors were investigated. Furthermore, these CS-CDHA carriers were examined by transmission electron microscopy, electron spectroscopy for chemical analysis, and X-ray diffraction. The release behavior of the biomolecules was controlled by the CS/CDHA ratios and cross-linked agents. By increasing the concentration of CS and the concentration of the cross-linking agents, cross-linking within carriers increases, and the release rate of the biomolecules is decreased. Moreover, the release rate of the biomolecules from the CS-CDHA carriers at pH 4 was higher than that at pH 10, displaying a pH-sensitive behavior. Therefore, these CS-CDHA hydrogel beads may be useful for intelligent drug release and accelerate bone reconstruction.

  11. Biomolecule Analogues 2-Hydroxypyridine and 2-Pyridone Base Pairing on Ice Nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Rubovič, Peter; Pysanenko, Andriy; Lengyel, Jozef; Nachtigallová, Dana; Fárník, Michal

    (2016). ISSN 1089-5639 R&D Projects: GA ČR GA14-14082S Institutional support: RVO:61388955 Keywords : ice nanoparticles * hydrogen bonding * biomolecules Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.693, year: 2014

  12. Extraction of Biomolecules Using Phosphonium-Based Ionic Liquids + K3PO4 Aqueous Biphasic Systems

    Directory of Open Access Journals (Sweden)

    Cláudia L. S. Louros

    2010-04-01

    Full Text Available Aqueous biphasic systems (ABS provide an alternative and efficient approach for the extraction, recovery and purification of biomolecules through their partitioning between two liquid aqueous phases. In this work, the ability of hydrophilic phosphonium-based ionic liquids (ILs to form ABS with aqueous K3PO4 solutions was evaluated for the first time. Ternary phase diagrams, and respective tie-lines and tie-lines length, formed by distinct phosphonium-based ILs, water, and K3PO4 at 298 K, were measured and are reported. The studied phosphonium-based ILs have shown to be more effective in promoting ABS compared to the imidazolium-based counterparts with similar anions. Moreover, the extractive capability of such systems was assessed for distinct biomolecules (including amino acids, food colourants and alkaloids. Densities and viscosities of both aqueous phases, at the mass fraction compositions used for the biomolecules extraction, were also determined. The evaluated IL-based ABS have been shown to be prospective extraction media, particularly for hydrophobic biomolecules, with several advantages over conventional polymer-inorganic salt ABS.

  13. Recovery of biomolecules from marinated herring (Clupea harengus) brine using ultrafiltration through ceramic membranes

    DEFF Research Database (Denmark)

    Gringer, Nina; Hosseini, Seyed Vali; Svendsen, Tore; Undeland, Ingrid; Christensen, Morten Lykkegaard; Baron, Caroline P.

    2015-01-01

    recovery of high value biomolecules such as proteins, fatty acids, minerals, and phenolic compounds. Chemical and biological oxygen demand (COD, BOD5) as well as total suspended solids (TSS) were also measured to follow the performance of the ultrafiltration. The retentates contained 75-82% (95% TSS and...

  14. Immobilization of biomolecules onto surfaces according to ultraviolet light diffraction patterns

    DEFF Research Database (Denmark)

    Petersen, Steffen B.; Gennaro, Ane Kold Di; Neves Petersen, Teresa;

    2010-01-01

    We developed a method for immobilization of biomolecules onto thiol functionalized surfaces according to UV diffraction patterns. UV light-assisted molecular immobilization proceeds through the formation of free, reactive thiol groups that can bind covalently to thiol reactive surfaces. We demons...

  15. A quasi-static continuum model describing interactions between plasmons and non-absorbing biomolecules

    Science.gov (United States)

    Salary, Mohammad Mahdi; Mosallaei, Hossein

    2015-06-01

    Interactions between the plasmons of noble metal nanoparticles and non-absorbing biomolecules forms the basis of the plasmonic sensors, which have received much attention. Studying these interactions can help to exploit the full potentials of plasmonic sensors in quantification and analysis of biomolecules. Here, a quasi-static continuum model is adopted for this purpose. We present a boundary-element method for computing the optical response of plasmonic particles to the molecular binding events by solving the Poisson equation. The model represents biomolecules with their molecular surfaces, thus accurately accounting for the influence of exact binding conformations as well as structural differences between different proteins on the response of plasmonic nanoparticles. The linear systems arising in the method are solved iteratively with Krylov generalized minimum residual algorithm, and the acceleration is achieved by applying precorrected-Fast Fourier Transformation technique. We apply the developed method to investigate interactions of biotinylated gold nanoparticles (nanosphere and nanorod) with four different types of biotin-binding proteins. The interactions are studied at both ensemble and single-molecule level. Computational results demonstrate the ability of presented model for analyzing realistic nanoparticle-biomolecule configurations. The method can provide comprehensive study for wide variety of applications, including protein structures, monitoring structural and conformational transitions, and quantification of protein concentrations. In addition, it is suitable for design and optimization of the nano-plasmonic sensors.

  16. Crisis vital desde una perspectiva de género

    OpenAIRE

    Castro, Eva; Flores López, Olga

    2004-01-01

    A continuación se presenta el caso de una mujer de 55 años que presenta una crisis de identidad, abordado desde una perspectiva de género y un modelo explicativo y terapéutico que incluye elementos del análisis transaccional y la terapia constructivista.

  17. Paradigma e Disciplina nas Perspectivas de Kuhn e Morin

    Directory of Open Access Journals (Sweden)

    Sérgio Luís Boeira

    2009-07-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 http://dx.doi.org/10.5007/1807-1384.2009v6n1p90 Este ensaio compara o conceito de paradigma nas perspectivas de Thomas Kuhn e Edgar Morin. Apesar da relevância internacional de suas obras e de suas contribuições para a história da ciência e para a filosofia da ciência, observa-se na literatura uma falta de estudos comparativos sobre suas principais idéias, o que tem gerado confusões e simplificações. O ensaio parte de extensa pesquisa de obras publicadas pelos autores em âmbito internacional. Na primeira seção, trata-se da perspectiva de Kuhn sobre diversas noções, como paradigma, matriz disciplinar, comunidade científica e incomensurabilidade. Na segunda, examina-se a perspectiva de Morin sobre paradigma disjuntor-redutor e paradigma da complexidade. Na terceira seção, comparam-se suas perspectivas sobre progresso científico, a partir da noção de disciplina, para discernir aspectos convergentes e divergentes em suas obras, resumidos nas conclusões. Palavras-chave: Paradigma; Disciplina; Filosofia da ciência.

  18. Preparation of supramolecular hydrogel-enzyme hybrids exhibiting biomolecule-responsive gel degradation.

    Science.gov (United States)

    Shigemitsu, Hajime; Fujisaku, Takahiro; Onogi, Shoji; Yoshii, Tatsuyuki; Ikeda, Masato; Hamachi, Itaru

    2016-09-01

    Hydrogelators are small, self-assembling molecules that form supramolecular nanofiber networks that exhibit unique dynamic properties. Development of supramolecular hydrogels that degrade in response to various biomolecules could potentially be used for applications in areas such as drug delivery and diagnostics. Here we provide a synthetic procedure for preparing redox-responsive supramolecular hydrogelators that are used to create hydrogels that degrade in response to oxidizing or reducing conditions. The synthesis takes ∼2-4 d, and it can potentially be carried out in parallel to prepare multiple hydrogelator candidates. This described solid-phase peptide synthesis protocol can be used to produce previously described hydrogelators or to construct a focused molecular library to efficiently discover and optimize new hydrogelators. In addition, we describe the preparation of redox-responsive supramolecular hydrogel-enzyme hybrids that are created by mixing aqueous solutions of hydrogelators and enzymes, which requires 2 h for completion. The resultant supramolecular hydrogel-enzyme hybrids exhibit gel degradation in response to various biomolecules, and can be rationally designed by connecting the chemical reactions of the hydrogelators with enzymatic reactions. Gel degradation in response to biomolecules as triggers occurs within a few hours. We also describe the preparation of hydrogel-enzyme hybrids arrayed on flat glass slides, enabling high-throughput analysis of biomolecules such as glucose, uric acid, lactate and so on by gel degradation, which is detectable by the naked eye. The protocol requires ∼6 h to prepare the hydrogel-enzyme hybrid array and to complete the biomolecule assay. PMID:27560177

  19. Equidad y politicas universitarias: perspectivas desde latinoamerica

    Directory of Open Access Journals (Sweden)

    José Alberto Yuni

    2014-08-01

    Full Text Available En este artículo nos proponemos abordar algunas cuestiones de la equidad en la Educación Superior, desde la singular perspectiva de la realidad latinoamericana. Nuestro interés radica en dar cuenta de los modos y posiciones teóricas a través de las cuales se definen políticas de equidad en el campo de la Educación Superior y se establecen sentidos y significados sociales en torno a ellas. En la primera parte se realiza una breve caracterización de los escenarios de la Educación Superior en Latinoamérica, tanto en lo que se refiere a los procesos socio-políticos de carácter estructural, como a la dinámica de los sistemas de Educación Superior. En la segunda parte, se efectúa una reconstrucción conceptual que nos permita mostrar los desplazamientos operados en las políticas universitarias de las últimas décadas y que han desembocado en la implementación de las llamadas políticas de equidad. En la tercera parte del artículo, se analizan diferentes niveles de especificación del concepto de equidad en las dinámicas universitarias, las que dan cuenta de su potencial productivo de prácticas. Finalmente, se describen algunas de las iniciativas más importantes desplegadas en los últimos años por algunos países de la región, enmarcadas en políticas de equidad, señalando sus efectos y alcances.ABSTRACTIn this article we aim to address some issues of equity in higher education, from the particular perspective of Latin American reality. Our interest is highlight the fact of the theoretical and methodological positions through which equity policies are defined in the field of higher education and how social meanings and ways are established around them. In the first part, a brief description of the scenarios of higher education in Latin America is done, both in regard to the socio-political structural processes and the dynamics of higher education systems. In the second part, a conceptual reconstruction is approached to allow

  20. Effect of biomolecules adsorption on oxide layers developed on metallic materials used in cooling water systems

    International Nuclear Information System (INIS)

    This thesis was carried out in the frame of the BIOCOR ITN European project, in collaboration with the industrial partner RSE S.p.A. (Italy). Metallic materials commonly used in cooling systems of power plants may be affected by bio-corrosion induced by biofilm formation. The objective of this work was to study the influence of biomolecules adsorption, which is the initial stage of biofilm formation, on the electrochemical behaviour and the surface chemical composition of three metallic materials (70Cu-30Ni alloy, 304L stainless steel and titanium) in seawater environments. In a first step, the interactions between a model protein, the bovine serum albumin (BSA), and the surface of these materials were investigated. Secondly, tightly bound (TB) and loosely bound (LB) extracellular polymeric substances (EPS), that play a fundamental role in the different stages of biofilm formation, maturation and maintenance, were extracted from Pseudomonas NCIMB 2021 marine strain, and their effects on oxide layers were also evaluated. For that purpose, electrochemical measurements (corrosion potential E(corr) vs time, polarization curves and electrochemical impedance spectroscopy (EIS)) performed during the very first steps of oxide layers formation (1 h immersion time) were combined to surface analysis by X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ions mass spectrometry (ToF-SIMS). Compared to 70Cu-30Ni alloy in static artificial seawater (ASW) without biomolecules, for which a thick duplex oxide layer (outer redeposited Cu2O layer and inner oxidized nickel layer) is shown, the presence of BSA, TB EPS and LB EPS leads to a mixed oxide layer (oxidized copper and nickel) with a lower thickness. In the biomolecules-containing solutions, this oxide layer is covered by an adsorbed organic layer, mainly composed of proteins. A model is proposed to analyse impedance data obtained at E(corr). The results show a slow-down of the anodic reaction in the presence of

  1. Calculation and visualization of atomistic mechanical stresses in nanomaterials and biomolecules.

    Directory of Open Access Journals (Sweden)

    Andrew T Fenley

    Full Text Available Many biomolecules have machine-like functions, and accordingly are discussed in terms of mechanical properties like force and motion. However, the concept of stress, a mechanical property that is of fundamental importance in the study of macroscopic mechanics, is not commonly applied in the biomolecular context. We anticipate that microscopical stress analyses of biomolecules and nanomaterials will provide useful mechanistic insights and help guide molecular design. To enable such applications, we have developed Calculator of Atomistic Mechanical Stress (CAMS, an open-source software package for computing atomic resolution stresses from molecular dynamics (MD simulations. The software also enables decomposition of stress into contributions from bonded, nonbonded and Generalized Born potential terms. CAMS reads GROMACS topology and trajectory files, which are easily generated from AMBER files as well; and time-varying stresses may be animated and visualized in the VMD viewer. Here, we review relevant theory and present illustrative applications.

  2. The Patentability of Biomolecules – Does Online Bioinformatics Compromise Novelty?

    Directory of Open Access Journals (Sweden)

    Anton Hutter

    2006-04-01

    Full Text Available Researchers are becoming increasingly concerned that the confidentiality of their novel biomolecule sequences is being jeopardised, particularly when these sequences are either submitted to sequence databases or uploaded as query terms onto internet-based bioinformatic software suites. The researcher’s fears stem from the fact that the actual uploading of their sequences acts as a novelty destroying prior disclosure or publication, and that this may subsequently preclude valid patent protection for the sequences. This article addresses the key issues involved in the analyses of biomolecules, highlighting potential risks taken by many researchers in regard to patent protection and suggests possible ways in which these risks may be mitigated.

  3. Immobilization of biomolecules onto surfaces according to ultraviolet light diffraction patterns

    Energy Technology Data Exchange (ETDEWEB)

    Bjoern Petersen, Steffen; Kold di Gennaro, Ane; Neves-Petersen, Maria Teresa; Skovsen, Esben; Parracino, Antonietta

    2010-10-01

    We developed a method for immobilization of biomolecules onto thiol functionalized surfaces according to UV diffraction patterns. UV light-assisted molecular immobilization proceeds through the formation of free, reactive thiol groups that can bind covalently to thiol reactive surfaces. We demonstrate that, by shaping the pattern of the UV light used to induce molecular immobilization, one can control the pattern of immobilized molecules onto the surface. Using a single-aperture spatial mask, combined with the Fourier transforming property of a focusing lens, we show that submicrometer (0.7 {mu}m) resolved patterns of immobilized prostate-specific antigen biomolecules can be created. If a dual-aperture spatial mask is used, the results differ from the expected Fourier transform pattern of the mask. It appears as a superposition of two diffraction patterns produced by the two apertures, with a fine structured interference pattern superimposed.

  4. Antioxidants from defatted Indian Mustard (Brassica Juncea) protect biomolecules against in vitro oxidation.

    Science.gov (United States)

    Dua, Anita; Chander, Subhash; Agrawal, Sharad; Mahajan, Ritu

    2014-10-01

    Indian mustard seeds were defatted by distillation with hexane and the residue extracted with methanol was analyzed for potential antioxidants; ascorbate, riboflavin, and polyphenols. Gallic acid (129.796 μg), caffeic acid (753.455 μg), quercetin (478.352 μg) and kaempferol (48.060 μg)/g dry seeds were identified by HPLC analysis of the extract. DPPH free radical scavenging activity and protection of lipids, proteins and DNA against metal induced oxidation was examined. Defatted mustard seed remnant had excellent free radical scavenging activity and protects biomolecules with IC50 value 2.0-2.25 mg dry seed weight. Significant content of polyphenols in methanol extract of defatted seeds accounts for high antioxidant potential. We are the first to report the detailed analysis of antioxidant composition and protection of biomolecules against oxidative damage by methanol extract of mustard seed remnant after oil extraction. PMID:25320478

  5. UNA PERSPECTIVA NEUROCIENTÍFICA SOBRE LA HISTERIA

    Directory of Open Access Journals (Sweden)

    Lucía Amoruso

    2010-01-01

    Full Text Available En la última década, el desarrollo y la puesta en marcha delas modernas técnicas de neuroimagen en el campo de laneurociencia cognitiva han proporcionado una nueva vía deacercamiento al estudio experimental de algunos trastornosmentales. Dentro de esta perspectiva, denominada por algunosautores “neuropsiquiatría cognitiva”, la histeria (o trastornode conversión, de acuerdo con la clasificación psiquiátricaactual ha cobrado un amplio protagonismo. De acuerdo conlo anterior, el objetivo del presente trabajo consiste en introducirestudios pioneros basados en una perspectiva neurocientíficade la histeria. Conviene destacar que, si bien estosaportan evidencia significativa sobre algunas de las áreascerebrales y las disfunciones cognitivas comprometidas enel mencionado trastorno, los resultados obtenidos a la fechadistan aún de ser concluyentes.

  6. Nanohybrid structure analysis and biomolecule release behavior of polysaccharide-CDHA drug carriers

    OpenAIRE

    Huang, Li-Ying; Liu, Ting-Yu; Liu, Tse-Ying; Mevold, Andreas; Hardiansyah, Andri; Liao, Hung-Chou; Lin, Chin-Ching; Yang, Ming-Chien

    2013-01-01

    Nanoscaled polymer composites were prepared from polysaccharide chitosan (CS) and Ca-deficient hydroxyapatite (CDHA). CS-CDHA nanocomposites were synthesized by in situ precipitation at pH 9, and the CS-CDHA carriers were then fabricated by ionic cross-linking methods using tripolyphosphate and chemical cross-linking methods by glutaraldehyde and genipin. Certain biomolecules such as vitamin B12, cytochrome c, and bovine serum albumin were loaded into the CS-CDHA carriers, and their release b...

  7. Nanocoating for biomolecule delivery using layer-by-layer self-assembly

    OpenAIRE

    KEENEY, M; Jiang, X. Y.; Yamane, M.; Lee, M.; Goodman, S.; Yang, F.

    2015-01-01

    Since its introduction in the early 1990s, layer-by-layer (LbL) self-assembly of films has been widely used in the fields of nanoelectronics, optics, sensors, surface coatings, and controlled drug delivery. The growth of this industry is propelled by the ease of film manufacture, low cost, mild assembly conditions, precise control of coating thickness, and versatility of coating materials. Despite the wealth of research on LbL for biomolecule delivery, clinical translation has been limited an...

  8. Nanoscale surface properties and interaction with fundamental biomolecules of chlorite and phlogopite

    OpenAIRE

    Moro, Daniele

    2014-01-01

    The surface properties of minerals have important implications in geology, environment, industry and biotechnology and for certain aspects in the research on the origin of life. This research project aims to widen the knowledge on the nanoscale surface properties of chlorite and phlogopite by means of advanced methodologies, and also to investigate the interaction of fundamental biomolecules, such as nucleotides, RNA, DNA and amino acid glycine with the surface of the selected phyllosilica...

  9. Development of radioactively labelled cancer seeking biomolecules for targeted radiotherapy. Uruguay

    International Nuclear Information System (INIS)

    The main objective of this project is the labelling and quality control of biomolecules with radionuclides beta emitters with high purity and stability. Techniques and methodology for labelling with 188Re, 153Sm, and 125I as well as quality controls were done according to the recommendations of the first research coordination meeting of this CRP. Also some useful chelators reported in the literature were synthesized in our laboratory)

  10. NV Center Electron Paramagnetic Resonance of a Single Nanodiamond Attached to an Individual Biomolecule

    OpenAIRE

    Teeling-Smith, Richelle M.; Jung, Young Woo; Scozzaro, Nicolas; Cardellino, Jeremy; Rampersaud, Isaac; North, Justin A.; Šimon, Marek; Bhallamudi, Vidya P.; Rampersaud, Arfaan; Johnston-Halperin, Ezekiel; Poirier, Michael G.; Hammel, P. Chris

    2015-01-01

    A key limitation of electron paramagnetic resonance (EPR), an established and powerful tool for studying atomic-scale biomolecular structure and dynamics is its poor sensitivity, samples containing in excess of 10^12 labeled biomolecules are required in typical experiments. In contrast, single molecule measurements provide improved insights into heterogeneous behaviors that can be masked by ensemble measurements and are often essential for illuminating the molecular mechanisms behind the func...

  11. FUNCTIONALIZATION OF CARBON NANOTUBES BY DIFFERENT BIOMOLECULES FOR STABLE DISPERSION IN WATER

    OpenAIRE

    O. M. Burlaka; Ya. V. Pirko; Kolomys, O. F.; P. S. Smertenko; V. O. Glazunova; Konstantinova, T. E.; A. I. Yemets; Ya. B. Blume

    2015-01-01

    To select the effective methods for functionalizing carbon nanotubes and to compare the ability of a number of biological molecules (plasmid DNA, ATP, mix of deoxyribonucleoside triphosphates, bovine serum albumin, compounds of vitreous humor extract and sodium humate) to interact non-covalently with carbon nanotubes and mediate their dispersion in an aqueous medium was the aim of the work. Properties of carbon nanotubes-biomolecules conjugates were characterized using ultraviolet...

  12. A newly built setup for small bio-molecule fragmentation study in Lanzhou

    International Nuclear Information System (INIS)

    A new setup for studying ion induced small bio-molecule fragmentation processes has been built in Lanzhou, China. A preliminary collision experiment between a 30 keV He2+ ion beam and gas phase adenine molecules was performed. Partial TOF spectra associated to well-defined scattered projectile final charge states, He+ or He0 were recorded. Coincidence spectra between fragments were also obtained.

  13. Imparting biomolecules to a metal-organic framework material by controlled DNA tetrahedron encapsulation

    OpenAIRE

    Yongmei Jia; Benmei Wei; Ruixue Duan; Ying Zhang; Boya Wang; Abdul Hakeem; Nannan Liu; Xiaowen Ou; Shaofang Xu; Zhifei Chen; Xiaoding Lou; Fan Xia

    2014-01-01

    Recently, the incorporation of biomolecules in Metal-organic frameworks (MOFs) attracts many attentions because of controlling the functions, properties and stability of trapped molecules. Although there are few reports on protein/MOFs composites and their applications, none of DNA/MOFs composite is reported, as far as we know. Here, we report a new composite material which is self-assembled from 3D DNA (guest) and pre-synthesized MOFs (host) by electrostatic interactions and hydrophilic inte...

  14. Experimental Beam Studies of Plasma-generated Species Interaction with Polymeric Materials and Biomolecules

    OpenAIRE

    Chung, Ting-Ying

    2012-01-01

    Low temperature plasma-based processes are used extensively in many modern technologies. It is thus very important to understand plasma and surface interactions in order to improve plasma processes and design of functional materials. Applying a high vacuum beam system, this dissertation studies the fundamental mechanisms of plasma species-induced modification of materials for two critical applications: manufacturing of semiconductor devices and surface deactivation of infectious biomolecules....

  15. Synthesis of new pyrrole-containing biomolecules as building blocks for functionalized polypyrroles in nanobiotechnology

    International Nuclear Information System (INIS)

    New pyrroles were synthesized wherein biomolecules such as α-amino acids, peptides or carbohydrates are attached to position 1 or 3 via suitable linkers. These conjugates were copolymerized with pyrrole by chemical polymerisation alone giving corresponding copolymers or in the presence of magnetic iron oxid nanoparticles resulting in functionalized core-shell-nanoparticles. Such products are interesting for biosensing, imaging or separation of biomaterials. They were characterized by several methods such as TEM, HRTEM, FTIR and measuring of magnetization.

  16. Etymology of transition metal biomolecules as a learning aid in Biological Chemistry

    International Nuclear Information System (INIS)

    Numerous functional biomolecules are associated with metals, i.e. the metallobiomolecules; more specifically, some are dependent on transition metals required for several crucial biological roles. Nevertheless, their names can lead to ambiguous interpretations concerning the properties and performances of this group of biological molecules. Their etymology may be useful by providing a more perceptive insight into their features. However, etymology can lead to incongruous conclusions, requiring an especially careful approach to prevent errors. Examples illustrating these subjects shall be examined (author)

  17. Del enfoque por tareas a la perspectiva co-accional

    OpenAIRE

    Puren, Christian

    2004-01-01

    Se presenta una comparaci??n entre ???enfoque por tareas???, como lo desarrollaron los didactas anglo-sajones dentro del enfoque comunicativo, y la ???perspectiva accional??? del reciente Marco europeo com??n de referencia del Consejo de Europa (2001). Interesa distinguir entre tareas (de aprendizaje) y acciones (sociales, fuera del aula), y mantener el concepto de ???tarea??? en el nivel de abstracci??n ???transmetodol??gico???, pues permite distinguir entre diferentes ???orie...

  18. Los derivados financieros desde una perspectiva jurídica

    OpenAIRE

    Cuartas Gómez, Lucas; Sierra Vásquez, Paula

    2008-01-01

    El importante aumento en el uso de los contratos de derivados en Colombia1 y el mundo, además de la dificultad que puede traer su comprensión, nos ha llevado a escribir el presente trabajo, con el fin de darle a el lector una perspectiva general sobre el funcionamiento de estos instrumentos financieros, su regulación en Colombia y la forma como éstos se han venido contratando a nivel internacional.

  19. Familia y enfermedad de alzheimer. Una perspectiva cualitativa

    OpenAIRE

    Algado Ferrer, María Teresa; Basterra, Ángel; Garrigós Monerris, José Ignacio

    1997-01-01

    Este trabajo estudia, desde una perspectiva sociológica cualitativa, los efectos, que el cuidado de un enfermo de Alzheimer, producen en la vida personal, familiar y social de sus familiares cuidadores, e intenta poner de manifiesto que estamos ante un problema no sólo médico o sanitario, sino también familiar y social, que requiere una mayor atención.

  20. Perspectiva espiritual de la mujer con cáncer

    Directory of Open Access Journals (Sweden)

    Milena Alexandra Galvis-López

    2011-01-01

    Full Text Available Objetivo: comparar la perspectiva espiritual de las mujeres diagnosticadas con cáncer propio de su género (seno, útero, ovarios y de las mujeres diagnosticadas con otros tipos de cáncer. Método: diseño cuantitativo de tipo descriptivo comparativo, de corte transversal. Se empleó una encuesta sociodemográfica para caracterizar la población y la Escala de perspectiva espiritual de Pamela Reed, a la cual se le realizó el análisis de confiabilidad que reportó un alfa de Cronbach de 0,799 en el grupo 1 y 0,763 en el grupo 2. La muestra incluyó a 100 mujeres que se encuentran en tratamiento contra el cáncer. Resultados: la perspectiva espiritual de las mujeres con cáncer propio de su género es moderada al igual que la de las mujeres con otros tipos de cáncer; al hacer la comparación de estos dos grupos no se encontró evidencia estadística que demostrara una diferencia significativa. Discusión: los resultados de este estudio aportan nuevos elementos para el cuidado de las mujeres con enfermedad oncológica y señalan que una perspectiva espiritual moderada puede ser un potencial para su cuidado integral, en el que la enfermera reconozca sus objetivos en el cuidado de la mujer como un ser total, más que el tipo de cáncer que tiene.

  1. Graphene-Templated Synthesis of Magnetic Metal Organic Framework Nanocomposites for Selective Enrichment of Biomolecules.

    Science.gov (United States)

    Cheng, Gong; Wang, Zhi-Gang; Denagamage, Sachira; Zheng, Si-Yang

    2016-04-27

    Successful control of homogeneous and complete coating of graphene or graphene-based composites with well-defined metal organic framework (MOF) layers is a great challenge. Herein, novel magnetic graphene MOF composites were constructed via a simple strategy for self-assembly of well-distributed, dense, and highly porous MOFs on both sides of graphene nanosheets. Graphene functionalized with magnetic nanoparticles and carboxylic groups on both sides was explored as the backbone and template to direct the controllable self-assembly of MOFs. The prepared composite materials have a relatively high specific surface area (345.4 m(2) g(-1)), and their average pore size is measured to be 3.2 nm. Their relatively high saturation magnetization (23.8 emu g(-1)) indicates their strong magnetism at room temperature. Moreover, the multifunctional composite was demonstrated to be a highly effective affinity material in selective extraction and separation of low-concentration biomolecules from biological samples, in virtue of the size-selection property of the unique porous structure and the excellent affinity of the composite materials. Besides providing a solution for the construction of well-defined functional graphene-based MOFs, this work could also contribute to selective extraction of biomolecules, in virtue of the universal affinity between immobilized metal ions and biomolecules. PMID:27046460

  2. Recent trends in carbon nanomaterial-based electrochemical sensors for biomolecules: A review

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Cheng; Denno, Madelaine E.; Pyakurel, Poojan; Venton, B. Jill, E-mail: jventon@virginia.edu

    2015-08-05

    Carbon nanomaterials are advantageous for electrochemical sensors because they increase the electroactive surface area, enhance electron transfer, and promote adsorption of molecules. Carbon nanotubes (CNTs) have been incorporated into electrochemical sensors for biomolecules and strategies have included the traditional dip coating and drop casting methods, direct growth of CNTs on electrodes and the use of CNT fibers and yarns made exclusively of CNTs. Recent research has also focused on utilizing many new types of carbon nanomaterials beyond CNTs. Forms of graphene are now increasingly popular for sensors including reduced graphene oxide, carbon nanohorns, graphene nanofoams, graphene nanorods, and graphene nanoflowers. In this review, we compare different carbon nanomaterial strategies for creating electrochemical sensors for biomolecules. Analytes covered include neurotransmitters and neurochemicals, such as dopamine, ascorbic acid, and serotonin; hydrogen peroxide; proteins, such as biomarkers; and DNA. The review also addresses enzyme-based electrodes that are used to detect non-electroactive species such as glucose, alcohols, and proteins. Finally, we analyze some of the future directions for the field, pointing out gaps in fundamental understanding of electron transfer to carbon nanomaterials and the need for more practical implementation of sensors. - Highlights: • We review the types of carbon nanomaterials used in electrochemical sensors. • Different materials and sensor designs are compared for classes of biomolecules. • Future challenges of better sensor design and implementation are assessed.

  3. Radiation synthesis of hydrogels with diprotic acid moieties and their use in the adsorption of biomolecules

    International Nuclear Information System (INIS)

    Radiation synthesis of diprotic acid moieties containing poly (N-vinyl 2- pyrrolidone) and polyacrylamide hydrogels and their use in the adsorption of biomolecules such as enzymes, proteins and drugs have been investigated. Hydrogels with varying cross-linked densities and ionic moieties were prepared from the ternary systems of N-vinyl 2-pyrrolidone/itaconic acid/water and acrylamide/maleic acid/water by irradiating with γ rays at ambient temperature. For the characterization of network structure of hydrogels new equations were derived. Determination of average molecular weight between cross-links of hydrogels sensitive to pH changes of the swelling medium was investigated. In order to explain the influence of other external stimuli such as temperature and ionic strength of the swelling medium and the type of the buffer solution on the equilibrium swelling properties were investigated. The effect of these external stimuli on the biomolecule adsorption capacity of hydrogels were investigated for bovine serum albumin, α-amylase, invertase, model and commercial drugs. The results show that the hydrogels prepared in this study can be considered as potential carriers for the biomolecules and the drug delivery systems. (author)

  4. Electron Paramagnetic Resonance of a Single NV Nanodiamond Attached to an Individual Biomolecule.

    Science.gov (United States)

    Teeling-Smith, Richelle M; Jung, Young Woo; Scozzaro, Nicolas; Cardellino, Jeremy; Rampersaud, Isaac; North, Justin A; Šimon, Marek; Bhallamudi, Vidya P; Rampersaud, Arfaan; Johnston-Halperin, Ezekiel; Poirier, Michael G; Hammel, P Chris

    2016-05-10

    Electron paramagnetic resonance (EPR), an established and powerful methodology for studying atomic-scale biomolecular structure and dynamics, typically requires in excess of 10(12) labeled biomolecules. Single-molecule measurements provide improved insights into heterogeneous behaviors that can be masked in ensemble measurements and are often essential for illuminating the molecular mechanisms behind the function of a biomolecule. Here, we report EPR measurements of a single labeled biomolecule. We selectively label an individual double-stranded DNA molecule with a single nanodiamond containing nitrogen-vacancy centers, and optically detect the paramagnetic resonance of nitrogen-vacancy spins in the nanodiamond probe. Analysis of the spectrum reveals that the nanodiamond probe has complete rotational freedom and that the characteristic timescale for reorientation of the nanodiamond probe is slow compared with the transverse spin relaxation time. This demonstration of EPR spectroscopy of a single nanodiamond-labeled DNA provides the foundation for the development of single-molecule magnetic resonance studies of complex biomolecular systems. PMID:27166812

  5. Biomolecule conjugation strategy using novel water-soluble phosphine-based chelating agents

    Science.gov (United States)

    Katti, Kattesh V.; Gali, Hariprasad; Volkert, Wynn A.

    2004-08-24

    This invention describes a novel strategy to produce phosphine-functionalized biomolecules (e.g. peptides or proteins) for potential use in the design and development of site-specific radiopharmaceuticals for diagnosis or therapy of specific cancers. Hydrophilic alkyl phosphines, in general, tend to be oxidatively unstable. Therefore, incorporation of such phosphine functionalities on peptide (and other biomolecule) backbones, without oxidizing the P.sup.III centers, is difficult. In this context this discovery reports on a new technology by which phosphines, in the form of bifunctional chelating agents, can be directly incorporated on biomolecular backbones using manual synthetic or solid phase peptide synthesis methodologies. The superior ligating abilities of phosphine ligands, with various diagnostically (e.g. TC-99m) or therapeutically (e.g. Re186/188, Rh-105, Au-199) useful radiometals, coupled with the findings that the resulting complexes demonstrate high in vivo stability makes this approach useful in the development of radiolabeled biomolecules for applications in the design of tumor-specific radiopharmaceuticals.

  6. A new finite element and finite difference hybrid method for computing electrostatics of ionic solvated biomolecule

    Science.gov (United States)

    Ying, Jinyong; Xie, Dexuan

    2015-10-01

    The Poisson-Boltzmann equation (PBE) is one widely-used implicit solvent continuum model for calculating electrostatics of ionic solvated biomolecule. In this paper, a new finite element and finite difference hybrid method is presented to solve PBE efficiently based on a special seven-overlapped box partition with one central box containing the solute region and surrounded by six neighboring boxes. In particular, an efficient finite element solver is applied to the central box while a fast preconditioned conjugate gradient method using a multigrid V-cycle preconditioning is constructed for solving a system of finite difference equations defined on a uniform mesh of each neighboring box. Moreover, the PBE domain, the box partition, and an interface fitted tetrahedral mesh of the central box can be generated adaptively for a given PQR file of a biomolecule. This new hybrid PBE solver is programmed in C, Fortran, and Python as a software tool for predicting electrostatics of a biomolecule in a symmetric 1:1 ionic solvent. Numerical results on two test models with analytical solutions and 12 proteins validate this new software tool, and demonstrate its high performance in terms of CPU time and memory usage.

  7. Recent trends in carbon nanomaterial-based electrochemical sensors for biomolecules: A review

    International Nuclear Information System (INIS)

    Carbon nanomaterials are advantageous for electrochemical sensors because they increase the electroactive surface area, enhance electron transfer, and promote adsorption of molecules. Carbon nanotubes (CNTs) have been incorporated into electrochemical sensors for biomolecules and strategies have included the traditional dip coating and drop casting methods, direct growth of CNTs on electrodes and the use of CNT fibers and yarns made exclusively of CNTs. Recent research has also focused on utilizing many new types of carbon nanomaterials beyond CNTs. Forms of graphene are now increasingly popular for sensors including reduced graphene oxide, carbon nanohorns, graphene nanofoams, graphene nanorods, and graphene nanoflowers. In this review, we compare different carbon nanomaterial strategies for creating electrochemical sensors for biomolecules. Analytes covered include neurotransmitters and neurochemicals, such as dopamine, ascorbic acid, and serotonin; hydrogen peroxide; proteins, such as biomarkers; and DNA. The review also addresses enzyme-based electrodes that are used to detect non-electroactive species such as glucose, alcohols, and proteins. Finally, we analyze some of the future directions for the field, pointing out gaps in fundamental understanding of electron transfer to carbon nanomaterials and the need for more practical implementation of sensors. - Highlights: • We review the types of carbon nanomaterials used in electrochemical sensors. • Different materials and sensor designs are compared for classes of biomolecules. • Future challenges of better sensor design and implementation are assessed

  8. Elemental labelling combined with liquid chromatography inductively coupled plasma mass spectrometry for quantification of biomolecules: A review

    OpenAIRE

    Kretschy, Daniela; Koellensperger, Gunda; Hann, Stephan

    2012-01-01

    This article reviews novel quantification concepts where elemental labelling is combined with flow injection inductively coupled plasma mass spectrometry (FI-ICP-MS) or liquid chromatography inductively coupled plasma mass spectrometry (LC–ICP-MS), and employed for quantification of biomolecules such as proteins, peptides and related molecules in challenging sample matrices. In the first sections an overview on general aspects of biomolecule quantification, as well as of labelling will be pre...

  9. SOBRE LOS CAMBIOS DE PERSPECTIVA EN EL CONOCIMIENTO

    Directory of Open Access Journals (Sweden)

    LUZ MARINA BARRETO

    2007-01-01

    Full Text Available El propósito de este artículo es explorar el significado y los alcances de los cambios de perspectiva que a veces ocurren cuando vemos las cosas desde el punto de vista teórico, al producirse un cambio de paradigma en el conocimiento, o, si las vemos desde el uso práctico de la razón, cuando se produce un cambio en la personalidad o una "conversión". La mera cuestión sobre la posibilidad de un cambio radical de perspectiva es filosófica en un sentido profundo: sugiere la existencia de un campo de conocimiento metafísico que sería "libre" respecto de las proyecciones categoriales específicas y determinaciones que descansan en el sujeto de conocimiento, de manera que sería posible ver las cosas desde un punto de vista radicalmente diferente, uno que no sería posible sino al interior de un paradigma. Mis intuiciones son, en primer lugar, que la pregunta por la naturaleza de los cambios de perspectiva, metafísica como es, es más importante para la epistemología de lo que se ha admitido en la filosofía analítica y, en segundo lugar, que esta pregunta puede ser encarada no necesariamente al interior del marco de referencia de la metafísica, sino desde un concepto amplio de razón. En este sentido, los cambios de perspectiva pueden ser entendidos como una posibilidad que sólo puede hacerse inteligible dentro de una noción unificada de la razón, una concepción que ha sido ignorada por concepciones epistemológicas que acentúan su lado instrumental y que podemos remontar a algunos conceptos de la ontología fenomenológica que han sido re-interpretados a través de la lente de la teoría de la experiencia kantiana. Finalmente, sugiero que si miramos los cambios de perspectiva desde el punto de vista de una concepción unificada de la razón, de ello resulta una teoría del conocimiento mucho más fluida y más ligada al uso práctico de la razón que lo que se admite en las epistemologías analíticas que fueron populares durante

  10. Microfossils, biomolecules and biominerals in carbonaceous meteorites: implications to the origin of life

    Science.gov (United States)

    Hoover, Richard B.

    2012-11-01

    Environmental and Field Emission Scanning Electron Microscopy (ESEM and FESEM) investigations have shown that a wide variety of carbonaceous meteorites contain the remains of large filaments embedded within freshly fractured interior surfaces of the meteorite rock matrix. The filaments occur singly or in dense assemblages and mats and are often encased within carbon-rich, electron transparent sheaths. Electron Dispersive X-ray Spectroscopy (EDS) spot analysis and 2D X-Ray maps indicate the filaments rarely have detectable nitrogen levels and exhibit elemental compositions consistent with that interpretation that of the meteorite rock matrix. Many of the meteorite filaments are exceptionally well-preserved and show evidence of cells, cell-wall constrictions and specialized cells and processes for reproduction, nitrogen fixation, attachment and motility. Morphological and morphometric analyses permit many of the filaments to be associated with morphotypes of known genera and species of known filamentous trichomic prokaryotes (cyanobacteria and sulfur bacteria). The presence in carbonaceous meteorites of diagenetic breakdown products of chlorophyll (pristane and phytane) along with indigenous and extraterrestrial chiral protein amino acids, nucleobases and other life-critical biomolecules provides strong support to the hypothesis that these filaments represent the remains of cyanobacteria and other microorganisms that grew on the meteorite parent body. The absence of other life-critical biomolecules in the meteorites and the lack of detectable levels of nitrogen indicate the filaments died long ago and can not possibly represent modern microbial contaminants that entered the stones after they arrived on Earth. This paper presents new evidence for microfossils, biomolecules and biominerals in carbonaceous meteorites and considers the implications to some of the major hypotheses for the Origin of Life.

  11. Stable functionalization of germanium surface and its application in biomolecules immobilization

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Qi [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); University of Chinese Academy of Sciences, No.19A, Yuquan Road, Beijing 100049 (China); Xu, Baojian [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); Ye, Lin [Sate Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); University of Chinese Academy of Sciences, No.19A, Yuquan Road, Beijing 100049 (China); Tang, Teng; Huang, Shanluo; Du, Xiaowei [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); University of Chinese Academy of Sciences, No.19A, Yuquan Road, Beijing 100049 (China); Bian, Xiaojun; Zhang, Jishen [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); Di, Zengfeng, E-mail: zfdi@mail.sim.ac.cn [Sate Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); Jin, Qinghui [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); Zhao, Jianlong, E-mail: jlzhao@mail.sim.ac.cn [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China)

    2014-10-15

    Highlights: • An effective method to immobilize biomolecules on the functionalized Ge surface. • The surface of Ge was functionalized with 11-Mercaptoundecanoic acid (11-MUA). • Stable and uniform SAMs was obtained on Ge surface after 11-MUA treatment. • The functionalized Ge was employed as substrate for protein immobilization. • Paving the way of Ge for further applications in bioelectronics field. - Abstract: As a typical semiconductor material, germanium (Ge) has the potential to be utilized in microelectronics and bioelectronics. Herein, we present a simple and effective method to immobilize biomolecules on the surface of functionalized Ge. The surface oxide of Ge was removed with the pretreatment of hydrochloric acid and the Cl-terminated Ge reacted with 11-Mercaptoundecanoic acid (11-MUA). The surface of Ge was coated with 11-MUA self-assembled monolayers (SAMs) due to the bonding reaction between the sulfhydryl group of 11-MUA and Cl-terminated Ge. Furthermore, typical biomolecule, a green fluorescent protein was chosen to be immobilized on the surface of the functionalized Ge. Contact angle analysis, atomic force microscopy and X-ray photoelectron spectroscopy were used to study the characteristics including wettability, stability, roughness and component of the functionalized Ge, respectively. Fluorescence microscopy was utilized to indicate the efficiency of protein immobilization on the surface of the functionalized Ge. With these studies, stable and uniform functionalized monolayer was obtained on the surface of Ge after 11-MUA treatment and the functionalized Ge was effectively applied in protein immobilization. Furthermore, this study may pave the way for further applications such as the integration of bioelectronics and biosensors with the attractive semiconductor material-Ge in future work.

  12. Study on the preparation and stability of 188Re biomolecules via EHDP

    International Nuclear Information System (INIS)

    A direct labelling technique via ethane-1-hydroxy-1,1-diphosphonic acid (EHDP) as a weak competing ligand was developed for the preparation of several biomolecules: 188 Re-monoclonal antibody ior cea1 against carcinoembryonic antigen (188 Re-MoAb), biotinylated 188Re-MoAb (188 Re-MoAb-biotin), 188 Re-polyclonal IgG (188 Re-IgG), 188 Re-peptide (somatostatine analogue peptide b-(2-naphtyl)-D-Ala-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-amide), 188 Re-MoAb fragments (188 Re-F(ab')2) and biotinylated 188 Re-F(ab')2 (188 Re-F(ab')2-biotin). The reaction conditions such as pH, temperature, weak ligand concentration and stannous chloride concentration were optimized during the radiolabelling of each biomolecule. Before the labelling procedure, disulphide bridge groups of the biomolecules were reduced with 2-mercaptoethanol (2-ME). To obtain 188 Re labelled antibodies and peptides in high radiochemical yields (>90%) via EHDP, it was necessary to use acidic conditions and a high concentration of stannous chloride to allow the redox reaction Re+7→Re+5:Re+4. The labelling of MoAb and F(ab')2 with 188Re via EHDP was also evaluated employing a pretargeted technique by avidin-biotin strategy in normal mice, demonstrating that the 188Re-labelled biotinylated antibodies are stable complexes in vivo. The 188Re-peptide complex prepared by this method, was stable for 24 h and no radiolytic degradation was observed. (author)

  13. Non-linear vibrational modes in biomolecules: A periodic orbits description

    Energy Technology Data Exchange (ETDEWEB)

    Kampanarakis, Alexandros [Department of Chemistry, University of Crete, and Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (FORTH), Vasilika Vouton, Heraklion 71110, Crete (Greece); Farantos, Stavros C., E-mail: farantos@iesl.forth.gr [Department of Chemistry, University of Crete, and Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (FORTH), Vasilika Vouton, Heraklion 71110, Crete (Greece); Daskalakis, Vangelis; Varotsis, Constantinos [Department of Environmental Science and Technology, Cyprus University of Technology, 31 Archbishop Kyprianos St., P.O. Box 50329, 3603 Lemesos (Cyprus)

    2012-05-03

    Graphical abstract: Vibrational frequency shifts in Fe{sup IV} = O species of the active site of cytochrome c oxidase are attributed to changes in the surrounding Coulomb field. Periodic orbits analysis assists to find the most anharmonic modes in model biomolecules. Highlights: Black-Right-Pointing-Pointer Periodic orbits are extended to multidimensional potentials of biomolecules. Black-Right-Pointing-Pointer Highly anharmonic vibrational modes and center-saddle bifurcations are detected. Black-Right-Pointing-Pointer Vibrational frequencies shifts in Oxoferryl species of CcO are observed. - Abstract: The vibrational harmonic normal modes of a molecule, which are valid at energies close to an equilibrium point (a minimum, maximum or saddle of the potential energy surface), are extended by periodic orbits to high energies where anharmonicity and coupling of the degrees of freedom are significant. In this way the assignment of the spectra, and thus the extraction of dynamics in highly excited molecules, can be obtained. New vibrational modes emanating from bifurcations of periodic orbits and long living localized trajectories signal the birth and localization of new quantum states. In this article we review and further study non-linear vibrational modes for model biomolecules such as alanine dipeptide and the active site in the oxoferryl oxidation state of the enzyme cytochrome c oxidase. We locate periodic orbits which exhibit high anhamonicity and lead to center-saddle bifurcations. These modes are associated to an isomerization process in alanine dipeptide and to frequency shifts in the oxoferryl observed by modifying the Coulomb field around the Imidazole-Fe{sup IV} = O species.

  14. Cuidar de Idosos numa ILPI na Perspectiva de Cuidadoras Formais

    Directory of Open Access Journals (Sweden)

    Mariana Pedroza Silva

    2015-02-01

    Full Text Available O objetivo deste estudo foi investigar na perspectiva de cuidadoras formais as concepções sobre o que é ser uma pessoa idosa. Participaram da pesquisa, 40 cuidadoras profissionais, sendo a maioria casada, e com idades variando entre 26 e 60 anos. Utilizou-se um questionário com questões abertas, sendo as respostas analisadas por meio da técnica proposta por Bardin. Os resultados evidenciaram que as subcategorias mais destacadas foram as concepções favoráveis sobre o que é ser uma pessoa idosa.  

  15. Cuidar de Idosos numa ILPI na Perspectiva de Cuidadoras Formais

    OpenAIRE

    Mariana Pedroza Silva; Deusivania Vieira da Silva Falcão

    2015-01-01

    O objetivo deste estudo foi investigar na perspectiva de cuidadoras formais as concepções sobre o que é ser uma pessoa idosa. Participaram da pesquisa, 40 cuidadoras profissionais, sendo a maioria casada, e com idades variando entre 26 e 60 anos. Utilizou-se um questionário com questões abertas, sendo as respostas analisadas por meio da técnica proposta por Bardin. Os resultados evidenciaram que as subcategorias mais destacadas foram as concepções favoráveis sobre o que é ser uma pessoa idosa...

  16. Perspectivas del aprendizaje organizacional como catalizador de escenarios competitivos

    OpenAIRE

    Jorge del Río Cortina; Diego Fernando Santisteban Rojas

    2011-01-01

    El presente artículo aborda los diferentes referentes teóricos de aprendizaje organizacional desde dos rutas, del individuo a la organización y desde la perspectiva de la organización al individuo. Los hallazgos más sobresalientes están dirigidos a resaltar las orientaciones de cada uno de los autores concentrados por clúster, es así como se observa que los diferentes autores presentan orientaciones a los procesos, capacidades individuales, cambios del entorno, trabajo en equipo y competitivi...

  17. Capital de Marca desde la perspectiva del consumidor

    OpenAIRE

    José Luis Saavedra Torres

    2004-01-01

    El objetivo de este artículo es explorar los conceptos teóricos del Capital de Marca desde la perspectiva del comportamiento del consumidor, como un intento de revisar los basamentos que constituyen su formación. Los planteamientos realizados forman parte de una investigación cualitativa de las propuestas de cuatro autores que formulan modelos para definir las fuentes, métodos para construir y elementos para determinar los beneficios del Capital de Marca, tanto para la organizació...

  18. La perspectiva cualitativa en los estudios sobre pobreza

    OpenAIRE

    Mateo Pérez, Miguel A.

    2002-01-01

    Los estudios sobre pobreza internacional han estado marcados por el enfoque cuantitativo. Sin embargo desde hace unos años los estudios cualitativos están adquiriendo una gran relevancia. Este artículo presenta las características de un estudio cualitativo sobre pobreza y género realizado en España durante los últimos tres años, estableciendo algunas líneas de trabajo básicas para el estudio de la pobreza desde la perspectiva cualitativa.

  19. El Bienestar en Perspectiva Ético-Económica

    OpenAIRE

    Juan Diego Castrillón Cordovéz

    2006-01-01

    Este ensayo expone que la perspectiva sobre el bienestar en la economía requiere hoy de una dimensión social como base para la competitividad global, no sólo desde las nuevas tendencias sobre la responsabilidad social corporativa sino considerando la vuelta a los orígenes en la economía clásica, surgida como ciencia a partir de la reflexión en la filosofía moral en relación con el bien común, la utilidad, la riqueza y los valores. El bienestares tratado en este documento como el reto fundamen...

  20. Perspectivas sobre el servicio público en Europa

    OpenAIRE

    Perona Páez, Juan José; Barbeito Veloso, Ma. Luz

    2008-01-01

    Las nuevas modalidades de interactividad y participación ciudadana que brinda Internet se consagran, de nuevo, como uno de los asuntos que más interés suscitan entre los investigadores, aunque esta vez la Red también es analizada desde otras perspectivas ciertamente interesantes, como el papel que desempeña en el consumo de información de actualidad frente a otros medios, o el uso que de ella hacen los adolescentes. Aunque Internet es, sin lugar a dudas, uno de los objetos de estudio que con ...

  1. MEZCLA DEL MARKETING VERDE: UNA PERSPECTIVA TEÓRICA

    OpenAIRE

    Thel Augusto Monteiro; Antonio Carlos Giuliani; Judith Cavazos-Arroyo; Nadia Kassouf Pizzinatto

    2015-01-01

    Este artículo aborda una perspectiva teórica al respecto de la mezcla de marketing y su aplicabilidad en las prácticas del marketing verde. Se trata de un estudio cualitativo, de carácter exploratorio, desarrollado a través del análisis de datos secundarios sobre el tema, utilizado como forma de unir la práctica y la teoría presentada por los autores analizados en el período comprendido entre 2003 y 2012. Se ofrece una breve síntesis sobre los conceptos de marketing verde, sus características...

  2. Extraction of Biomolecules Using Phosphonium-Based Ionic Liquids + K3PO4 Aqueous Biphasic Systems

    OpenAIRE

    Louros, Cláudia L. S.; Cláudio, Ana Filipa M.; Neves, Catarina M. S. S.; Freire, Mara G.; Marrucho, Isabel M.; Jérôme Pauly; Coutinho, João A. P.

    2010-01-01

    Aqueous biphasic systems (ABS) provide an alternative and efficient approach for the extraction, recovery and purification of biomolecules through their partitioning between two liquid aqueous phases. In this work, the ability of hydrophilic phosphonium-based ionic liquids (ILs) to form ABS with aqueous K3PO4 solutions was evaluated for the first time. Ternary phase diagrams, and respective tie-lines and tie-lines length, formed by distinct phosphonium-based ILs, water, and K3PO4 at 298 K, we...

  3. EPR-based approach for the localization of paramagnetic metal ions in biomolecules.

    Science.gov (United States)

    Abdullin, Dinar; Florin, Nicole; Hagelueken, Gregor; Schiemann, Olav

    2015-02-01

    Metal ions play an important role in the catalysis and folding of proteins and oligonucleotides. Their localization within the three-dimensional fold of such biomolecules is therefore an important goal in understanding structure-function relationships. A trilateration approach for the localization of metal ions by means of long-range distance measurements based on electron paramagnetic resonance (EPR) is introduced. The approach is tested on the Cu(2+) center of azurin, and factors affecting the precision of the method are discussed. PMID:25522037

  4. Exploring the nanoscale dynamics of biomolecules with optical microcavities (Conference Presentation)

    Science.gov (United States)

    Vollmer, Frank

    2016-03-01

    Medicine as well as biology increasingly rely on the use of cutting-edge physics and engineering, in order to pursue the next generation nanomedical applications and to address fundamental questions in the life sciences. Central to this task is the study of micro- and nano systems, focusing on how engineered systems combined with natural ones can advance sensing, medicine, and our understanding of how biological systems work. My research addresses these important questions with state-of-the-art biosensor technologies, capable of detecting single biomolecules and their dynamics; and resolving the kinetics of biomolecular systems on timescales ranging from few nanoseconds to several hours

  5. Mass spectrometry in structural biology and biophysics architecture, dynamics, and interaction of biomolecules

    CERN Document Server

    Kaltashov, Igor A; Desiderio, Dominic M; Nibbering, Nico M

    2012-01-01

    The definitive guide to mass spectrometry techniques in biology and biophysics The use of mass spectrometry (MS) to study the architecture and dynamics of proteins is increasingly common within the biophysical community, and Mass Spectrometry in Structural Biology and Biophysics: Architecture, Dynamics, and Interaction of Biomolecules, Second Edition provides readers with detailed, systematic coverage of the current state of the art. Offering an unrivalled overview of modern MS-based armamentarium that can be used to solve the most challenging problems in biophysics, structural biol

  6. Electrokinetic separation of biomolecules through multiple nano-pores on membrane

    Science.gov (United States)

    Kim, Yunho; Cha, Misun; Choi, Yosep; Joo, Hyunsang; Lee, Junghoon

    2013-03-01

    We demonstrate a nanoporous membrane device integrated with an on-chip microfluidic platform for the electrokinetic separation of biomolecules. This platform offers a thin (500 nm) film of anodized aluminum oxide directly fabricated and suspended onto a silicon substrate, assembled into a compact microfluidic device. We successfully showed the electrokinetic transport of ssDNA through the nano-porous membrane under various conditions. Size exclusive biomolecular separation driven by electric field was verified with the complex of thrombin and thrombin aptamer. This architecture enables an on-chip device for binary separation and size exclusive filtration targeted to various applications such as molecular detection and purification.

  7. Marketing de lugar: estado da arte e perspectivas futuras

    Directory of Open Access Journals (Sweden)

    Marco Antonio de Moraes Ocke

    2014-12-01

    Full Text Available O objetivo neste trabalho é contribuir com o repensar da natureza e do significado do marketing de lugar presente na literatura, descrevendo as três principais perspectivas influentes em seu desenvolvimento – promoção, planejamento e branding – e apresentar uma análise crítica de seu processo de evolução. No intuito de orientar o entendimento, evitar interpretações individuais e propor uma linguagem comum, a análise compreende a convergência das perspectivas em um conceito caracterizado como uma importante ferramenta de gerenciamento das trocas que ocorrem em âmbito territorial visando ao desenvolvimento socioeconômico da localidade. Como contribuição, sugere-se uma estruturação para investigações futuras identificando lacunas entre a teoria do marketing de lugar e a forma como é compreendido, assim como as dificuldades significativas para sua implementação.

  8. Simplified TiO2 force fields for studies of its interaction with biomolecules

    Science.gov (United States)

    Luan, Binquan; Huynh, Tien; Zhou, Ruhong

    2015-06-01

    Engineered TiO2 nanoparticles have been routinely applied in nanotechnology, as well as in cosmetics and food industries. Despite active experimental studies intended to clarify TiO2's biological effects, including potential toxicity, the relation between experimentally inferred nanotoxicity and industry standards for safely applying nanoparticles remains somewhat ambiguous with justified concerns. Supplemental to experiments, molecular dynamics simulations have proven to be efficacious in investigating the molecular mechanism of a biological process occurring at nanoscale. In this article, to facilitate the nanotoxicity and nanomedicine research related to this important metal oxide, we provide a simplified force field, based on the original Matsui-Akaogi force field but compatible to the Lennard-Jones potentials normally used in modeling biomolecules, for simulating TiO2 nanoparticles interacting with biomolecules. The force field parameters were tested in simulating the bulk structure of TiO2, TiO2 nanoparticle-water interaction, as well as the adsorption of proteins on the TiO2 nanoparticle. We demonstrate that these simulation results are consistent with experimental data/observations. We expect that simulations will help to better understand the interaction between TiO2 and molecules.

  9. Towards a Mechanism-Based Understanding of Vital Effects: Biomolecules Influence Mg/Ca in Calcite

    Science.gov (United States)

    Stephenson, A. E.; Nelson, E. J.; Wu, K. J.; de Yoreo, J. J.; Dove, P. M.

    2006-12-01

    Recent findings from our group suggest that the chemistry of biomolecules present at sites of mineral formation have a strong influence on the structure of water near calcite surfaces (Elhadj et al., CGD, 2006) and exercise predictable controls on the rate of calcite growth (Elhadj et al., submitted). Observing the extent to which biomolecules can mediate growth processes leads us to hypothesize that they also have measurable influence over impurity (Mg, Sr) contents. If true, this could be a significant contributor to the widely documented 'vital effects' that complicate interpretations of paleoenvironments, largely based on chemical signatures found in the skeletal remains of organisms. We use in situ AFM to measure the growth rate of calcite at the nanoscale under controlled solution compositions and at characterized chemical driving force. The relationship between the presence of carboxyl- rich peptides in solution during growth and the magnesium content in the resulting calcite was quantified using time-of-flight SIMS. This new work with tof-SIMS has validated previous compositional maps of Mg distributions collected by electron microprobe, and has yielded new insights into controls on impurity content. We are using similar methods to also determine factors that influence impurity contents of calcites grown in solutions at seawater ionic strength.

  10. Biomolecules preserved in ca. 168 million year old fossil conifer wood

    Science.gov (United States)

    Marynowski, Leszek; Otto, Angelika; Zatoń, Michał; Philippe, Marc; Simoneit, Bernd R. T.

    2007-03-01

    Biomarkers are widely known to occur in the fossil record, but the unaltered biomolecules are rarely reported from sediments older than Paleogene. Polar terpenoids, the natural products most resistant to degradation processes, were reported mainly from the Tertiary conifers, and the oldest known are Cretaceous in age. In this paper, we report the occurrence of relatively high concentrations of ferruginol derivatives and other polar diterpenoids, as well as their diagenetic products, in a conifer wood Protopodocarpoxylon from the Middle Jurassic of Poland. Thus, the natural product terpenoids reported in this paper are definitely the oldest polar biomolecules detected in geological samples. The extracted phenolic abietanes like ferruginol and its derivatives (6,7-dehydroferruginol, sugiol, 11,14-dioxopisiferic acid) are produced only by distinct conifer families (Cupressaceae s. l., Podocarpaceae and Araucariaceae), to which Protopodocarpoxylon could belong based on anatomical characteristics. Therefore, the natural product terpenoids are of great advantage in systematics of fossil plant remains older than Paleogene and lacking suitable anatomical preservation.

  11. Correlation dynamics and enhanced signals for the identification of serial biomolecules and DNA bases

    International Nuclear Information System (INIS)

    Nanopore-based sequencing has demonstrated a significant potential for the development of fast, accurate, and cost-efficient fingerprinting techniques for next generation molecular detection and sequencing. We propose a specific multilayered graphene-based nanopore device architecture for the recognition of single biomolecules. Molecular detection and analysis can be accomplished through the detection of transverse currents as the molecule or DNA base translocates through the nanopore. To increase the overall signal-to-noise ratio and the accuracy, we implement a new ‘multi-point cross-correlation’ technique for identification of DNA bases or other molecules on the single molecular level. We demonstrate that the cross-correlations between each nanopore will greatly enhance the transverse current signal for each molecule. We implement first-principles transport calculations for DNA bases surveyed across a multilayered graphene nanopore system to illustrate the advantages of the proposed geometry. A time-series analysis of the cross-correlation functions illustrates the potential of this method for enhancing the signal-to-noise ratio. This work constitutes a significant step forward in facilitating fingerprinting of single biomolecules using solid state technology. (paper)

  12. Disposable pen-shaped capillary gel electrophoresis cartridge for fluorescence detection of bio-molecules

    Science.gov (United States)

    Amirkhanian, Varoujan; Tsai, Shou-Kuan

    2014-03-01

    We introduce a novel and cost-effective capillary gel electrophoresis (CGE) system utilizing disposable pen-shaped gelcartridges for highly efficient, high speed, high throughput fluorescence detection of bio-molecules. The CGE system has been integrated with dual excitation and emission optical-fibers with micro-ball end design for fluorescence detection of bio-molecules separated and detected in a disposable pen-shaped capillary gel electrophoresis cartridge. The high-performance capillary gel electrophoresis (CGE) analyzer has been optimized for glycoprotein analysis type applications. Using commercially available labeling agent such as ANTS (8-aminonapthalene-1,3,6- trisulfonate) as an indicator, the capillary gel electrophoresis-based glycan analyzer provides high detection sensitivity and high resolving power in 2-5 minutes of separations. The system can hold total of 96 samples, which can be automatically analyzed within 4-5 hours. This affordable fiber optic based fluorescence detection system provides fast run times (4 minutes vs. 20 minutes with other CE systems), provides improved peak resolution, good linear dynamic range and reproducible migration times, that can be used in laboratories for high speed glycan (N-glycan) profiling applications. The CGE-based glycan analyzer will significantly increase the pace at which glycoprotein research is performed in the labs, saving hours of preparation time and assuring accurate, consistent and economical results.

  13. On macroscopic quantum phenomena in biomolecules and cells: from Levinthal to Hopfield.

    Science.gov (United States)

    Raković, Dejan; Dugić, Miroljub; Jeknić-Dugić, Jasmina; Plavšić, Milenko; Jaćimovski, Stevo; Setrajčić, Jovan

    2014-01-01

    In the context of the macroscopic quantum phenomena of the second kind, we hereby seek for a solution-in-principle of the long standing problem of the polymer folding, which was considered by Levinthal as (semi)classically intractable. To illuminate it, we applied quantum-chemical and quantum decoherence approaches to conformational transitions. Our analyses imply the existence of novel macroscopic quantum biomolecular phenomena, with biomolecular chain folding in an open environment considered as a subtle interplay between energy and conformation eigenstates of this biomolecule, governed by quantum-chemical and quantum decoherence laws. On the other hand, within an open biological cell, a system of all identical (noninteracting and dynamically noncoupled) biomolecular proteins might be considered as corresponding spatial quantum ensemble of these identical biomolecular processors, providing spatially distributed quantum solution to a single corresponding biomolecular chain folding, whose density of conformational states might be represented as Hopfield-like quantum-holographic associative neural network too (providing an equivalent global quantum-informational alternative to standard molecular-biology local biochemical approach in biomolecules and cells and higher hierarchical levels of organism, as well). PMID:25028662

  14. On Macroscopic Quantum Phenomena in Biomolecules and Cells: From Levinthal to Hopfield

    Directory of Open Access Journals (Sweden)

    Dejan Raković

    2014-01-01

    Full Text Available In the context of the macroscopic quantum phenomena of the second kind, we hereby seek for a solution-in-principle of the long standing problem of the polymer folding, which was considered by Levinthal as (semiclassically intractable. To illuminate it, we applied quantum-chemical and quantum decoherence approaches to conformational transitions. Our analyses imply the existence of novel macroscopic quantum biomolecular phenomena, with biomolecular chain folding in an open environment considered as a subtle interplay between energy and conformation eigenstates of this biomolecule, governed by quantum-chemical and quantum decoherence laws. On the other hand, within an open biological cell, a system of all identical (noninteracting and dynamically noncoupled biomolecular proteins might be considered as corresponding spatial quantum ensemble of these identical biomolecular processors, providing spatially distributed quantum solution to a single corresponding biomolecular chain folding, whose density of conformational states might be represented as Hopfield-like quantum-holographic associative neural network too (providing an equivalent global quantum-informational alternative to standard molecular-biology local biochemical approach in biomolecules and cells and higher hierarchical levels of organism, as well.

  15. Label-free imaging of biomolecules in food products using stimulated Raman microscopy

    Science.gov (United States)

    Roeffaers, Maarten B. J.; Zhang, Xu; Freudiger, Christian W.; Saar, Brian G.; Ruijven, Marjolein Van; Dalen, Gerard Van; Xiao, Chunhong; Xie, X. Sunney

    2011-02-01

    The development of methods that allow microscale studies of complex biomaterials based on their molecular composition is of great interest to a wide range of research fields. We show that stimulated Raman scattering (SRS) microscopy is an excellent analytical tool to study distributions of different biomolecules in multiphasic systems. SRS combines the label-free molecular specificity of vibrational spectroscopy with an enhanced sensitivity due to coherent excitation of molecular vibrations. Compared to previous imaging studies using coherent anti-Stokes Raman scattering microscopy, the main advantage of SRS microscopy is the absence of the unwanted nonresonant background, which translates into a superior sensitivity and undistorted vibrational spectra. We compare spectra of complex materials obtained with stimulated Raman scattering and spontaneous Raman scattering in the crowded fingerprint region. We find that, as expected, there is excellent correspondence and that the SRS spectra are free from interference from background fluorescence. In addition, we show high-resolution imaging of the distributions of selected biomolecules, such as lipids and proteins, in food products with SRS microscopy.

  16. Highly Sensitive Detection of Target Biomolecules on Cell Surface Using Gold Nanoparticle Conjugated with Aptamer Probe

    Science.gov (United States)

    Kim, Hyonchol; Terazono, Hideyuki; Hayashi, Masahito; Takei, Hiroyuki; Yasuda, Kenji

    2012-06-01

    A method of gold nanoparticle (Au NP) labeling with backscattered electron (BE) imaging of field emission scanning electron microscopy (FE-SEM) was applied for specific detection of target biomolecules on a cell surface. A single-stranded DNA aptamer, which specifically binds to the target molecule on a human acute lymphoblastic leukemia cell, was conjugated with a 20 nm Au NP and used as a probe to label its target molecule on the cell. The Au NP probe was incubated with the cell, and the interaction was confirmed using BE imaging of FE-SEM through direct counting of the number of Au NPs attached on the target cell surface. Specific Au NP-aptamer probes were observed on a single cell surface and their spatial distributions including submicron-order localizations were also clearly visualized, whereas the nonspecific aptamer probes were not observed on it. The aptamer probe can be potentially dislodged from the cell surface with treatment of nucleases, indicating that Au NP-conjugated aptamer probes can be used as sensitive and reversible probes to label target biomolecules on cells.

  17. Direct Covalent Biomolecule Immobilization on Plasma-Nanotextured Chemically Stable Substrates.

    Science.gov (United States)

    Tsougeni, K; Petrou, P S; Awsiuk, K; Marzec, M M; Ioannidis, N; Petrouleas, V; Tserepi, A; Kakabakos, S E; Gogolides, E

    2015-07-15

    A new method for direct covalent immobilization of protein molecules (including antibodies) on organic polymers with plasma-induced random micronanoscale topography and stable-in-time chemical functionality is presented. This is achieved using a short (1-5 min) plasma etching and simultaneous micronanotexturing process, followed by a fast thermal annealing step, which induces accelerated hydrophobic recovery while preserving important chemical functionality created by the plasma. Surface-bound biomolecules resist harsh washing with sodium dodecyl sulfate and other detergents even at elevated temperatures, losing less than 40% of the biomolecules bound even at the harshest washing conditions. X-ray photoelectron spectroscopy, secondary-ion mass spectrometry, and electron paramagnetic resonance are used to unveil the chemical modification of the plasma-treated and stabilized surfaces. The nanotextured and chemically stabilized surfaces are used as substrates for the development of immunochemical assays for the sensitive detection of C-reactive protein and salmonella lipopolysaccharides through immobilization of the respective analyte-specific antibodies onto them. Such substrates are stable for a period of 1 year with ambient storage. PMID:26098201

  18. Labelled biomolecules for targeted radiotherapy: biodistribution in mice with induced malignant tumours

    International Nuclear Information System (INIS)

    Antibodies and antibody fragments react against the cell membrane receptors or associated-antigens and can be 188Re-labelled and 153Sm-labelled as potential radioimmunotherapy (RIT) radiopharmaceuticals. A variety of malignant tumours over-express somatostatin receptors, proteins that can be targeted with radiolabelled biomolecules, like the lanreotide peptide. The direct labelling methods described here are easy to perform from a freeze-dried kit, are reliable and can be carried out in a hospital radiopharmacy. 188Re-lanreotide, thus prepared, shows affinity to HeLa cells and to the SiHa cells, both from a human cervical cancer, to 293 cells from human embryonic renal carcinoma and to B16F cells of murine melanoma, implanted in mice. 188Relanreotide standardized tumour uptake value SUV was 1.5 for the cervix cancer, 4.8 for the kidney tumour, and 0.8 for the melanoma metastases. Many of the neuroendocrine tumours which over-express somatostatin receptors are of epidermoid origin and the 4 induced tumours studied have many epidermoid characteristics. The cell origin might be the common factor to all these cancer cells, which bind 188Re-lanreotide. In conclusion: easy labelling methods with 188Re and 153Sm for biomolecules used for targeted therapy have been developed. 188Re-lanreotide binds to 4 different cancer cells implanted into mice. (author)

  19. Photoelectrochemical studies of DNA-tagged biomolecules on Au and Au/Ni/Au multilayer nanowires

    Directory of Open Access Journals (Sweden)

    Swaminathan Viswanathan

    2011-01-01

    Full Text Available Abstract The use of nanowires (NWs for labeling, sensing, and sorting is the basis of detecting biomolecules attached on NWs by optical and magnetic properties. In spite of many advantages, the use of biomolecules-attached NWs sensing by photoelectrochemical (PEC study is almost non-existent. In this article, the PEC study of dye-attached single-stranded DNA on Au NWs and Au-Ni-Au multilayer NWs prepared by pulse electrodeposition are investigated. Owing to quantum-quenching effect, the multilayer Au NWs exhibit low optical absorbance when compared with Au NWs. The tagged Au NWs show good fluorescence (emission at 570 nm, indicating significant improvement in the reflectivity. Optimum results obtained for tagged Au NWs attached on functionalized carbon electrodes and its PEC behavior is also presented. A twofold enhancement in photocurrent is observed with an average dark current of 10 μA for Au NWs coated on functionalized sensing electrode. The importance of these PEC and optical studies provides an inexpensive and facile processing platform for Au NWs that may be suitable for biolabeling applications.

  20. Synchrotron and small bio-molecules in gas phase and liquid environment: new opportunities in Brazil

    International Nuclear Information System (INIS)

    Full text: Two techniques are critically related to the photoelectric law, namely: photoelectron spectroscopy and photoelectron-photoion coincidence spectroscopy. Both are strongly used now a day within synchrotron laboratories. Our group is employing both to investigate fragmentation of bio-molecules in gas phase such as amino acids and DNA basis using V UV and soft x-ray photons. In the near future lager scale instruments developed in Brazil will allow unique opportunities to apply these two spectroscopic methods to molecules immersed in liquids such as water. We will present details from this advanced x-ray source and experimental stations with capabilities not present in other places in the world. Experiments connected to the molecular origin of live will be shown. Among them an experiment where we mimic the atmosphere at Titan moon producing bio- molecules will discussed. Another experiment will be presented where we test the Panspermia viability using special bacteria. We will also present experiments where frozen simple molecules connected to pre-biotic mate- rial are bombardment by UV photons and energetic particles showing interesting trends. Spectroscopic studies of gas phase photo-fragmentation of bio-molecules may be critical to understand in the future these molecules immersed in liquids. We plan to spend some time showing our recent results in this area. (author)

  1. A comparative study of biomolecule and polymer surface modifications by a surface microdischarge

    Science.gov (United States)

    Bartis, Elliot A. J.; Luan, Pingshan; Knoll, Andrew J.; Graves, David B.; Seog, Joonil; Oehrlein, Gottlieb S.

    2016-02-01

    Cold atmospheric plasma (CAP) sources are attractive sources of reactive species with promising industrial and biomedical applications, but an understanding of underlying surface mechanisms is lacking. A kHz-powered surface microdischarge (SMD) operating with N2/O2 mixtures was used to study the biological deactivation of two immune-stimulating biomolecules: lipopolysaccharide (LPS) and peptidoglycan (PGN), found in bacteria such as Escherichia coli and Staphylococcus aureus, respectively. Model polymers were also studied to isolate specific functional groups. Changes in the surface chemistry were measured to understand which plasma-generated species and surface modifications are important for biological deactivation. The overall goal of this work is to determine which effects of CAP treatment are generic and which bonds are susceptible to attack. CAP treatment deactivated biomolecules, oxidized surfaces, and introduced surface bound NO3. These effects can be controlled by the N2 fraction in O2 and applied voltage and vary among different target surfaces. The SMD was compared with an Ar/O2/N2-fed kHz-powered atmospheric pressure plasma jet and showed much higher surface modifications and surface chemistry tunability compared to the jet. Possible mechanisms are discussed and findings are compared with recent computational investigations. Our results demonstrate the importance of long-lived plasma-generated species and advance an atomistic understanding of CAP-surface interactions.

  2. Liquid-liquid extraction of biomolecules in downstream processing - A review paper

    Directory of Open Access Journals (Sweden)

    Silva M. E.

    2000-01-01

    Full Text Available Economic analysis shows that protein separation and purification are a very important aspect of biomolecules production and processing. This is particularly true for protein processing which, because of the complexity of the starting material, often requires many steps to reach the levels of purity required for medical and food applications. The separation specialists' task is to develop safe and simple processes to achieve products with a high level of purity. On a large scale, chromatography of proteins is not an easily applied method, although on a laboratory scale it is very effective and relatively simple. When it is scaled up, shortcomings such as discontinuity in the process, slow protein diffusion and large pressure drops in the system are seen. For these reasons a substantial research effort has been directed toward the use of aqueous two-phase systems (ATPSs to replace the initial steps in protein purification and chromatography. This article reviews the chronology and main ATPS fundamentals and discuss the broader applications of this type of system in the extraction and separation of biomolecules.

  3. Biomolecule-assisted synthesis of single-crystalline selenium nanowires and nanoribbons via a novel flake-cracking mechanism

    Science.gov (United States)

    Zhang, Bin; Ye, Xingchen; Dai, Wei; Hou, Weiyi; Zuo, Fan; Xie, Yi

    2006-01-01

    Recently, the biomolecule-assisted synthesis method has been a new and promising focus in the preparation of various nanomaterials. But current works mainly focus on the synthesis of metal nanoparticles and nanowires using macro-biomolecules (e.g. virus, protein and DNA) as templates in the presence of a reducing agent. Beta-carotene, one of the most common bio-antioxidants, can be oxidized to form species with both hydrophilic and hydrophobic ends, which can provide an in situ soft template for the synthesis of nanomaterials. Herein, a simple beta-carotene-assisted method was developed for the first time to synthesize t-Se nanowires and nanoribbons with high crystallinity. We demonstrate that beta-carotene serves as not only the reducing agent, but also an in situ template in the preparation of Se one-dimensional nanostructures. It is found that the growth mechanism of Se nanomaterials is different from the familiar sphere-wire process. A novel flake-cracking mechanism is proposed. By this biomolecule-assisted route, Te one-dimensional nanostructures and Pd nanowires were also fabricated. The assisted-biomolecule in our method may be spread to carotenoids and other antioxidants, and thus broaden the application fields of biomolecules. Our preliminary investigations have shown that the facile, solution-phase biomolecule-assisted method can be potentially extended to the preparation of other low-dimensional nanostructures. The synthesized t-Se nanowires and nanoribbons may serve as templates to generate other tubular functional nanomaterials and find applications in the studies of structure-property relationships as well as in the fabrication of nanoscale optoelectronic devices.

  4. Micropatterning of biomolecules on a glass substrate in fused silica microchannels by using photolabile linker-based surface activation

    International Nuclear Information System (INIS)

    We report on a straightforward method for creating micropatterns of multiple biomolecules. The anti-fouling agent 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer and a photolabile linker (PL) were covalently linked to an amino-terminated silane surface. Patterns were generated by selective removal of the MPC polymer via UV irradiation. Multiple micropatterns of fluorescein isothiocyanate (FITC)-labeled bovine serum albumin (BSA) and rhodamine-labeled goat fragment antigen-binding fragments (FAB) were deposited on a same glass substrate. We also employed micropatterning of multiple biomolecules in that Texas red-labeled BSA and FITC-labeled rabbit anti-mouse IgG were placed inside a microchannel. (author)

  5. Quantification of biomolecules in herring (Clupea harengus) industry processing waters and their recovery using electroflocculation and ultrafiltration

    DEFF Research Database (Denmark)

    Osman, Ali; Gringer, Nina; Svendsen, Tore;

    2015-01-01

    Four types of herring industry processing waters; refrigerated sea water (RSW), storage water (SW), processing water from cutting (PW) and pre-salting brines (SB) were subjected to chemical characterization and biomolecule recovery using electroflocculation (EF) and ultrafiltration (UF). The...... magnesium were the dominating trace elements. EF plus UF in series recovered up to 80% proteins and fatty acids from SB's and reduced chemical oxygen demand by 70%. Foaming and emulsifying properties of biomolecules were improved or unaffected by EF/UF treatment. To conclude, large amounts of biomass are...

  6. Hitos de la perspectiva molar del condicionamiento clásico

    OpenAIRE

    Andrés M. Pérez Acosta; Jairo A. Rozo; Herbert T. Baquero

    2003-01-01

    En este artículo se revisan los acontecimientos históricos fundamentales en la teoría del condicionamiento clásico como fenómeno psicológico comportamental o cognoscitivo, es decir, desde una perspectiva molar, en oposición a una perspectiva molecular, que es propia de las neurociencias. Se analizan los siguientes acontecimientos o hitos: la teoría reflexológica de Vladimir Bechterev, la perspectiva conductista radical de B. F. Skinner, el modelo de Rescorla y Wagner (1972),...

  7. LA PERSPECTIVA DEL USUARIO Y DEL SISTEMA EN LA INVESTIGACIÓN SOBRE EL COMPORTAMIENTO INFORMACIONAL

    OpenAIRE

    Aurora González Teruel

    2011-01-01

    Se exponen las principales perspectivas en el estudio del comportamiento informacional: la perspectiva del usuario y la del sistema. En el primer caso, se asume una visión global del proceso de búsqueda de información y se desarrollan modelos teóricos y metodológicos para guiar la investigación en este campo. Se presentan como ejemplo la teoría del Sense-Making de Brenda Dervin y el modelo de Proceso de Búsqueda de Información de Carol Kuhlthau. En el segundo caso, se asume una perspectiva pa...

  8. Identification of Biomolecular Building Blocks by Recognition Tunneling: Stride towards Nanopore Sequencing of Biomolecules

    Science.gov (United States)

    Sen, Suman

    DNA, RNA and Protein are three pivotal biomolecules in human and other organisms, playing decisive roles in functionality, appearance, diseases development and other physiological phenomena. Hence, sequencing of these biomolecules acquires the prime interest in the scientific community. Single molecular identification of their building blocks can be done by a technique called Recognition Tunneling (RT) based on Scanning Tunneling Microscope (STM). A single layer of specially designed recognition molecule is attached to the STM electrodes, which trap the targeted molecules (DNA nucleoside monophosphates, RNA nucleoside monophosphates or amino acids) inside the STM nanogap. Depending on their different binding interactions with the recognition molecules, the analyte molecules generate stochastic signal trains accommodating their "electronic fingerprints". Signal features are used to detect the molecules using a machine learning algorithm and different molecules can be identified with significantly high accuracy. This, in turn, paves the way for rapid, economical nanopore sequencing platform, overcoming the drawbacks of Next Generation Sequencing (NGS) techniques. To read DNA nucleotides with high accuracy in an STM tunnel junction a series of nitrogen-based heterocycles were designed and examined to check their capabilities to interact with naturally occurring DNA nucleotides by hydrogen bonding in the tunnel junction. These recognition molecules are Benzimidazole, Imidazole, Triazole and Pyrrole. Benzimidazole proved to be best among them showing DNA nucleotide classification accuracy close to 99%. Also, Imidazole reader can read an abasic monophosphate (AP), a product from depurination or depyrimidination that occurs 10,000 times per human cell per day. In another study, I have investigated a new universal reader, 1-(2-mercaptoethyl)pyrene (Pyrene reader) based on stacking interactions, which should be more specific to the canonical DNA nucleosides. In addition

  9. Identification of biomolecule mass transport and binding rate parameters in living cells by inverse modeling

    Directory of Open Access Journals (Sweden)

    Shirmohammadi Adel

    2006-10-01

    Full Text Available Abstract Background Quantification of in-vivo biomolecule mass transport and reaction rate parameters from experimental data obtained by Fluorescence Recovery after Photobleaching (FRAP is becoming more important. Methods and results The Osborne-Moré extended version of the Levenberg-Marquardt optimization algorithm was coupled with the experimental data obtained by the Fluorescence Recovery after Photobleaching (FRAP protocol, and the numerical solution of a set of two partial differential equations governing macromolecule mass transport and reaction in living cells, to inversely estimate optimized values of the molecular diffusion coefficient and binding rate parameters of GFP-tagged glucocorticoid receptor. The results indicate that the FRAP protocol provides enough information to estimate one parameter uniquely using a nonlinear optimization technique. Coupling FRAP experimental data with the inverse modeling strategy, one can also uniquely estimate the individual values of the binding rate coefficients if the molecular diffusion coefficient is known. One can also simultaneously estimate the dissociation rate parameter and molecular diffusion coefficient given the pseudo-association rate parameter is known. However, the protocol provides insufficient information for unique simultaneous estimation of three parameters (diffusion coefficient and binding rate parameters owing to the high intercorrelation between the molecular diffusion coefficient and pseudo-association rate parameter. Attempts to estimate macromolecule mass transport and binding rate parameters simultaneously from FRAP data result in misleading conclusions regarding concentrations of free macromolecule and bound complex inside the cell, average binding time per vacant site, average time for diffusion of macromolecules from one site to the next, and slow or rapid mobility of biomolecules in cells. Conclusion To obtain unique values for molecular diffusion coefficient and

  10. Flores e velas que falam no silêncio: perspectivas

    OpenAIRE

    Vale, Maíra Cavalcanti

    2014-01-01

    A presente pesquisa começou no mês de agosto de 2007, como um Projeto de Iniciação Científica (PIC) do CNPq vinculado à UnB, sob o título “Invasões e Remoções: uma perspectiva etnográfica comparada acerca dos movimentos urbanos de luta pela terra no Brasil e África do Sul (com especial atenção ao caso das Burial Societies)”, inserido no contexto maior da pesquisa da orientadora Dra. Antonádia Borges, que vem sendo desenvolvida há dois anos na África do Sul. O objetivo inicial era realizar uma...

  11. MEZCLA DEL MARKETING VERDE: UNA PERSPECTIVA TEÓRICA

    Directory of Open Access Journals (Sweden)

    Thel Augusto Monteiro

    2015-01-01

    Full Text Available Este artículo aborda una perspectiva teórica al respecto de la mezcla de marketing y su aplicabilidad en las prácticas del marketing verde. Se trata de un estudio cualitativo, de carácter exploratorio, desarrollado a través del análisis de datos secundarios sobre el tema, utilizado como forma de unir la práctica y la teoría presentada por los autores analizados en el período comprendido entre 2003 y 2012. Se ofrece una breve síntesis sobre los conceptos de marketing verde, sus características, acciones y la presentación de la mezcla de marketing adaptada al marketing verde. Se destaca la contribución de este artículo sobre el marketing verde y el avance de este tema, proponiendo una mezcla de marketing adaptada al marketing verde.

  12. Silver island film substrates for ultrasensitive fluorescence detection of (bio)molecules.

    Science.gov (United States)

    Szalkowski, Marcin; Ashraf, Khuram U; Lokstein, Heiko; Mackowski, Sebastian; Cogdell, Richard J; Kowalska, Dorota

    2016-01-01

    A silver island film (SIF) substrate was used to demonstrate that Metal-Enhanced Fluorescence (MEF) is a powerful tool to enable detection of emission from (bio)molecules at very low concentrations. The experiments were carried out with the Fenna-Matthews-Olson (FMO) pigment-protein complex from the photosynthetic green sulfur bacterium Chlorobaculum tepidum. FMO was diluted to a level, at which no emission was detectable on a glass substrate. In contrast, the fluorescence of FMO was readily observed on the SIF substrate, even though the emission wavelength of FMO is displaced by over 300 nm from the maximum of the plasmon resonance of the SIF layer. Estimated enhancements of the fluorescence intensity of FMO on SIF are about 40-fold. The enhancement factor correlates with the improvement of the signal-to-noise ratio for FMO emission on SIF substrates. PMID:26168991

  13. Microreactor and method for preparing a radiolabeled complex or a biomolecule conjugate

    Energy Technology Data Exchange (ETDEWEB)

    Reichert, David E; Kenis, Paul J. A.; Wheeler, Tobias D; Desai, Amit V; Zeng, Dexing; Onal, Birce C

    2015-03-17

    A microreactor for preparing a radiolabeled complex or a biomolecule conjugate comprises a microchannel for fluid flow, where the microchannel comprises a mixing portion comprising one or more passive mixing elements, and a reservoir for incubating a mixed fluid. The reservoir is in fluid communication with the microchannel and is disposed downstream of the mixing portion. A method of preparing a radiolabeled complex includes flowing a radiometal solution comprising a metallic radionuclide through a downstream mixing portion of a microchannel, where the downstream mixing portion includes one or more passive mixing elements, and flowing a ligand solution comprising a bifunctional chelator through the downstream mixing portion. The ligand solution and the radiometal solution are passively mixed while in the downstream mixing portion to initiate a chelation reaction between the metallic radionuclide and the bifunctional chelator. The chelation reaction is completed to form a radiolabeled complex.

  14. Automated astatination of biomolecules - a stepping stone towards multicenter clinical trials

    DEFF Research Database (Denmark)

    Aneheim, Emma; Albertsson, Per; Bäck, Tom; Jensen, Holger; Palm, Stig; Lindegren, Sture

    2015-01-01

    vector, which can guide the radiation to the cancer cells. Consequently, an appropriate method is required for coupling the nuclide to the vector. To increase the availability of astatine-211 radiopharmaceuticals for targeted alpha therapy, their production should be automated. Here, we present a method......To facilitate multicentre clinical studies on targeted alpha therapy, it is necessary to develop an automated, on-site procedure for conjugating rare, short-lived, alpha-emitting radionuclides to biomolecules. Astatine-211 is one of the few alpha-emitting nuclides with appropriate chemical and...... challenging, alpha-emitting radionuclide. In this work, we describe the process platform, and we demonstrate the production of both astaine-211, for preclinical use, and astatine-211 labelled antibodies....

  15. Measurement of small photodestruction rates of cold, charged biomolecules in an ion trap

    CERN Document Server

    Offenberg, D; Zhang, C B; Roth, B; Schiller, S

    2008-01-01

    In this work, we demonstrate measurements of photodestruction rates of translationally cold, charged biomolecules. The long-term stable storage of the molecular ions in an ion trap at ultra-high vacuum conditions allows measurement of small rates and verification that rates are linear in photodestruction laser intensity. Measurements were performed on singly protonated molecules of the organic compound glycyrrhetinic acid (C30H46O4), dissociated by a continuous-wave UV laser (266 nm) using different intensities. The molecules were sympathetically cooled by simultaneously trapped laser-cooled barium ions to translational temperatures of below 150 mK. Destruction rates of less than 0.05 s^-1 and a cross section of (1.1 +/- 0.1) * 10^-17 cm^2 have been determined. An extension to tunable UV laser sources would permit high-resolution dissociation spectroscopic studies on a wide variety of cold complex molecules.

  16. Latent analysis of unmodified biomolecules and their complexes in solution with attomole detection sensitivity

    Science.gov (United States)

    Yates, Emma V.; Müller, Thomas; Rajah, Luke; de Genst, Erwin J.; Arosio, Paolo; Linse, Sara; Vendruscolo, Michele; Dobson, Christopher M.; Knowles, Tuomas P. J.

    2015-10-01

    The study of biomolecular interactions is central to an understanding of function, malfunction and therapeutic modulation of biological systems, yet often involves a compromise between sensitivity and accuracy. Many conventional analytical steps and the procedures required to facilitate sensitive detection, such as the incorporation of chemical labels, are prone to perturb the complexes under observation. Here we present a ‘latent’ analysis approach that uses chemical and microfluidic tools to reveal, through highly sensitive detection of a labelled system, the behaviour of the physiologically relevant unlabelled system. We implement this strategy in a native microfluidic diffusional sizing platform, allowing us to achieve detection sensitivity at the attomole level, determine the hydrodynamic radii of biomolecules that vary by over three orders of magnitude in molecular weight, and study heterogeneous mixtures. We illustrate these key advantages by characterizing a complex of an antibody domain in the solution phase and under physiologically relevant conditions.

  17. Sawtooth patterns in biomolecules force-extension curves: an equilibrium-statistical-mechanics theory

    CERN Document Server

    Prados, A; Bonilla, L L

    2013-01-01

    We analyze the force-extension curve for a general class of systems, which are described at the mesoscopic level by a free energy depending on the extension of its components. Similarly to what is done in real experiments, the total length of the system is the controlled parameter. This imposes a global constraint in the minimization procedure leading to the equilibrium values of the extensions. As a consequence, the force-extension curve has multiple branches in a certain range of forces. The stability of these branches is governed by the free energy: there are a series of first-order phase transitions at certain values of the total length, in which the free energy itself is continuous but its first derivative, the force, has a finite jump. This behavior is completely similar to the one observed in real experiments with biomolecules like proteins, and other complex systems.

  18. Elemental speciation in biomolecules by LC-ICP-MS with magnetic sector and collision cell instruments

    International Nuclear Information System (INIS)

    A methodology that can monitor and identify inorganic elements in biological and environmental systems was developed. Size exclusion chromatography (SEC) separates biomolecules, which are then nebulized by a microconcentric nebulizer. The resulting aerosol is desolved and introduced into either a high resolution ICP-MS device or a quadrupole device with a collision cell. Because of the high sensitivity and spectral resolution and high sample introduction efficiency, many unusual or difficult elements, such as Cr, Se, Cd and U, can be observed at ambient levels bound to proteins in human serum. These measurements are made in only a few minutes without preliminary isolation and preconcentration steps. Serum samples can be titrated with spikes of various elements to determine which proteins bind a given metal and oxidation state. Experiments concerning the effects of breaking disulfide linkages and denaturation on metal binding in proteins were also investigated. Elemental distribution in liver extract was also obtained

  19. Elemental speciation in biomolecules by LC-ICP-MS with magnetic sector and collision cell instruments

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jin

    1999-11-08

    A methodology that can monitor and identify inorganic elements in biological and environmental systems was developed. Size exclusion chromatography (SEC) separates biomolecules, which are then nebulized by a microconcentric nebulizer. The resulting aerosol is desolved and introduced into either a high resolution ICP-MS device or a quadrupole device with a collision cell. Because of the high sensitivity and spectral resolution and high sample introduction efficiency, many unusual or difficult elements, such as Cr, Se, Cd and U, can be observed at ambient levels bound to proteins in human serum. These measurements are made in only a few minutes without preliminary isolation and preconcentration steps. Serum samples can be titrated with spikes of various elements to determine which proteins bind a given metal and oxidation state. Experiments concerning the effects of breaking disulfide linkages and denaturation on metal binding in proteins were also investigated. Elemental distribution in liver extract was also obtained.

  20. Structural Change of Biomolecules and Application of Synergistic Interaction by Radiation

    International Nuclear Information System (INIS)

    It is expected that motivation and basic technologies for the future R and D plans can be provided from the results of this study. This study has been done to develop fundamentals for radiation applications based on the existing radiation technology, and to establish technical basis for enhancing efficacy of radiation utilization by studying the simultaneous application of ionizing radiation with another factor. Application of radiation technology together with the existing technologies to enhance the physical, chemical, biological characteristics through structural changes of biomolecules will exert a favorable influence on the creation of de novo scientific and industrial values. A theoretical model for the combined action of ionizing radiation with another factor can make it possible to predict a prior the maximum value of synergistic interaction and the conditions for it. Furthermore, the results of this study give a clues for establishment of fundamental theories associated with positive efficacy of radiation applications

  1. The interplay of biomolecules and water at the origin of the active behavior of living organisms

    International Nuclear Information System (INIS)

    It is shown that the main component of living matter, namely liquid water, is not an ensemble of independent molecules but an ensemble of phase correlated molecules kept in tune by an electromagnetic (e.m) field trapped in the ensemble. This field and the correlated potential govern the interaction among biomolecules suspended in water and are in turn affected by the chemical interactions of molecules. In particular, the phase of the coherent fields appears to play an important role in this dynamics. Recent experiments reported by the Montagnier group seem to corroborate this theory. Some features of the dynamics of human organisms, as reported by psychotherapy, holistic medicine and Eastern traditions, are analyzed in this frame and could find a rationale in this context.

  2. Ultrafast conformational changes in biomolecules studied by time-resolved circular dichroism

    Science.gov (United States)

    Changenet-Barret, P.; Hache, F.

    2015-10-01

    Circular dichroism (CD) is known to be a very sensitive probe of molecular conformation, and it is in particular widely used in biochemistry. Measuring the CD as a function of time is therefore very appealing to access information on the dynamics of conformational changes in molecules or biomolecules. We have implemented such a time-resolved experiments in two complementary configurations: a sub-picosecond pump-probe one and a microsecond detection of CD coupled to a T-jump experiment. We present two experiments based on these techniques: the ultrafast motion of the carbonyl group in the chromophore of the Photoactive Yellow Protein after photoexcitation and the dynamics of thermal denaturation in model peptides.

  3. RESPONSABILIDADE SOCIAL CORPORATIVA: CONSTRUINDO UMA PERSPECTIVA PRÃ-GOVERNO

    Directory of Open Access Journals (Sweden)

    Ana Lucia Malheiros Guedes

    2008-09-01

    Full Text Available Ao fortalecer e disseminar em larga escala conceitos e discursos pró-mercado, a era da globalização fortaleceu as áreas de estratégia e marketing, em detrimento de conceitos e discursos pró-governo e da área de gestão pública. Esse quadro de assimetria contribuiu para a transformação de responsabilidade social corporativa (RSC em tópico de central importância para grandes empresas e para as áreas de marketing e de estratégia e também para a emergência de algumas críticas mais extremas. Este ensaio argumenta que esse processo de fortalecimento da literatura pró-mercado deve ser problematizado e que a área de gestão pública deve construir e disseminar uma perspectiva pró-governo em RSC. Apesar do desinteresse da área de gestão pública pelas áreas de estratégia e marketing, essa perspectiva pró-governo em RSC pode tanto revigorar a área de gestão pública no Brasil, quanto ajudar elevar a relevância das áreas de estratégia e marketing.

  4. Radiolabeled biomolecules for early cancer detection and therapy via angiogenesis targeting

    Energy Technology Data Exchange (ETDEWEB)

    Bouziotis, P. [Institute of Radioisotopes-Radiodiagnostic Products, N.C.S.R. ' Demokritos' , 153 10 Athens, Hellas (Greece)]. E-mail: pennybil@yahoo.gr; Psimadas, D. [Institute of Radioisotopes-Radiodiagnostic Products, N.C.S.R. ' Demokritos' , 153 10 Athens, Hellas (Greece): Biomedica Life Sciences SA, Athens, Hellas (Greece); Fani, M. [Institute of Radioisotopes-Radiodiagnostic Products, N.C.S.R. ' Demokritos' , 153 10 Athens, Hellas (Greece): Biomedica Life Sciences SA, Athens, Hellas (Greece); Gourni, E. [Institute of Radioisotopes-Radiodiagnostic Products, N.C.S.R. ' Demokritos' , 153 10 Athens, Hellas (Greece); Loudos, G. [Biomedical Simulations and Imaging Laboratory, N.T.U.A., Athens, Hellas (Greece); Xanthopoulos, S. [Institute of Radioisotopes-Radiodiagnostic Products, N.C.S.R. ' Demokritos' , 153 10 Athens, Hellas (Greece); Archimandritis, S.C. [Institute of Radioisotopes-Radiodiagnostic Products, N.C.S.R. ' Demokritos' , 153 10 Athens, Hellas (Greece); Varvarigou, A.D. [Institute of Radioisotopes-Radiodiagnostic Products, N.C.S.R. ' Demokritos' , 153 10 Athens, Hellas (Greece)

    2006-12-20

    Tumors cannot grow or metastasize without the formation of new blood vessels, i.e. without angiogenesis. A variety of anti-angiogenic agents leading to angiogenesis inhibition are in the clinical trial phase, among which are: (i) molecules which inhibit the action of Vascular Endothelial Growth Factors, VEGF and (ii) molecules which obstruct migration, differentiation and proliferation of endothelial cells, via their binding to receptors of the {alpha}{sub {nu}}{beta}{sub 3} integrins. Certain derivatives of the abovementioned categories, labeled with radionuclides, which emit {gamma}-radiation or {beta}-particles or positrons, have been proposed and are being evaluated as possible radiopharmaceuticals, for the detection and/or treatment of primary or metastatic cancer at an early stage. For the study of angiogenesis the following have been described: (a) antibodies targeting VEGF, labeled with radionuclides emitting {beta}- and/or {gamma}-radiation, which can be applied for the diagnosis and, possibly, for the treatment of cancer (b) peptide derivatives which contain the amino-acid sequence RGD (Arg-Gly-Asp) and compete for the {alpha}{sub {nu}}{beta}{sub 3} integrins, with the proteins of the stroma. It has been found that these radiolabeled biomolecules localize in tumors and can be used for the visualization and, possibly, for tumor eradication of primary and metastatic cancer. In our laboratory radiolabeling of biomolecules by beta and/or gamma emitters is a principal research goal. In the present work we are presenting our results on the labeling of monoclonal antibodies and peptides with {beta}- and {gamma}-emitting isotopes, as well as on their in vivo evaluation in experimental animal models, by use of specially dedicated imaging devices.

  5. Microfossils and biomolecules in carbonaceous meteorites: possibility of life in water-bearing asteroids and comets

    Science.gov (United States)

    Hoover, Richard B.

    2014-09-01

    It is well established that carbonaceous meteorites contain water, carbon, biogenic elements and a host of organic chemicals and biomolecules. Several independent lines of evidence indicate that the parent bodies of the CI1 and CM2 carbonaceous meteorites are most probably the C-type asteroids or cometary nuclei. Several of the protein amino acids detected in the meteorites exhibit chirality and have an excess of the L-enantiomer -- such as in the amino acids present in the proteins of all known life forms on Earth. Isotopic studies have established that the amino acids and nucleobases in the CI1 and CM2 carbonaceous meteorites are both indigenous and extraterrestrial. Optical and Scanning Electron Microscopy studies carried out by researchers during the past half century have revealed the presence of complex biogenic microstructures embedded in the rock-matrix of many of carbonaceous meteorites similar to extinct life-forms known as acritarchs and hystrichospheres. Carbonaceous meteorites also contain a wide variety of large filaments that exhibit the complex morphologies and correct size ranges of known genera and species of photosynthetic microorganisms such as cyanobacteria and diatoms. However, EDAX investigations have shown that these carbon-rich filaments typically have nitrogen content below the level of detection (hair and teeth of Pleistocene Mammoths. Hence, the absence of detectable nitrogen in the filaments provides direct evidence that they do not represent recent biological contaminants that invaded these meteorite stones after they were observed to fall to Earth. The spectral and fluorescence properties of pigments found in several species of terrestrial cyanobacteria which are similar to some microfossils found in carbonaceous meteorites may provide valuable clues to help search for evidence for biomolecules and life on the icy moons of Jupiter and Saturn, asteroids and comets.

  6. Elemental labelling combined with liquid chromatography inductively coupled plasma mass spectrometry for quantification of biomolecules: A review

    International Nuclear Information System (INIS)

    Highlights: ► Survey of bio-analytical approaches utilizing biomolecule labelling. ► Detailed discussion of methodology and chemistry of elemental labelling. ► Biomedical and bio-analytical applications of elemental labelling. ► FI-ICP-MS and LC–ICP-MS for quantification of elemental labelled biomolecules. ► Review of selected applications. - Abstract: This article reviews novel quantification concepts where elemental labelling is combined with flow injection inductively coupled plasma mass spectrometry (FI-ICP-MS) or liquid chromatography inductively coupled plasma mass spectrometry (LC–ICP-MS), and employed for quantification of biomolecules such as proteins, peptides and related molecules in challenging sample matrices. In the first sections an overview on general aspects of biomolecule quantification, as well as of labelling will be presented emphasizing the potential, which lies in such methodological approaches. In this context, ICP-MS as detector provides high sensitivity, selectivity and robustness in biological samples and offers the capability for multiplexing and isotope dilution mass spectrometry (IDMS). Fundamental methodology of elemental labelling will be highlighted and analytical, as well as biomedical applications will be presented. A special focus will lie on established applications underlining benefits and bottlenecks of such approaches for the implementation in real life analysis. Key research made in this field will be summarized and a perspective for future developments including sophisticated and innovative applications will given.

  7. Accurate and computationally efficient prediction of thermochemical properties of biomolecules using the generalized connectivity-based hierarchy.

    Science.gov (United States)

    Sengupta, Arkajyoti; Ramabhadran, Raghunath O; Raghavachari, Krishnan

    2014-08-14

    In this study we have used the connectivity-based hierarchy (CBH) method to derive accurate heats of formation of a range of biomolecules, 18 amino acids and 10 barbituric acid/uracil derivatives. The hierarchy is based on the connectivity of the different atoms in a large molecule. It results in error-cancellation reaction schemes that are automated, general, and can be readily used for a broad range of organic molecules and biomolecules. Herein, we first locate stable conformational and tautomeric forms of these biomolecules using an accurate level of theory (viz. CCSD(T)/6-311++G(3df,2p)). Subsequently, the heats of formation of the amino acids are evaluated using the CBH-1 and CBH-2 schemes and routinely employed density functionals or wave function-based methods. The calculated heats of formation obtained herein using modest levels of theory and are in very good agreement with those obtained using more expensive W1-F12 and W2-F12 methods on amino acids and G3 results on barbituric acid derivatives. Overall, the present study (a) highlights the small effect of including multiple conformers in determining the heats of formation of biomolecules and (b) in concurrence with previous CBH studies, proves that use of the more effective error-cancelling isoatomic scheme (CBH-2) results in more accurate heats of formation with modestly sized basis sets along with common density functionals or wave function-based methods. PMID:25068299

  8. Nuclear routing networks span between nuclear pore complexes and genomic DNA to guide nucleoplasmic trafficking of biomolecules

    OpenAIRE

    Malecki, Marek; Malecki, Bianca

    2012-01-01

    In health and disease, biomolecules, which are involved in gene expression, recombination, or reprogramming have to traffic through the nucleoplasm, between nuclear pore complexes (NPCs) and genomic DNA (gDNA). This trafficking is guided by the recently revealed nuclear routing networks (NRNs).

  9. Combinational Effect of Cell Adhesion Biomolecules and Their Immobilized Polymer Property to Enhance Cell-Selective Adhesion

    Directory of Open Access Journals (Sweden)

    Rio Kurimoto

    2016-01-01

    Full Text Available Although surface immobilization of medical devices with bioactive molecules is one of the most widely used strategies to improve biocompatibility, the physicochemical properties of the biomaterials significantly impact the activity of the immobilized molecules. Herein we investigate the combinational effects of cell-selective biomolecules and the hydrophobicity/hydrophilicity of the polymeric substrate on selective adhesion of endothelial cells (ECs, fibroblasts (FBs, and smooth muscle cells (SMCs. To control the polymeric substrate, biomolecules are immobilized on thermoresponsive poly(N-isopropylacrylamide-co-2-carboxyisopropylacrylamide (poly(NIPAAm-co-CIPAAm-grafted glass surfaces. By switching the molecular conformation of the biomolecule-immobilized polymers, the cell-selective adhesion performances are evaluated. In case of RGDS (Arg-Gly-Asp-Ser peptide-immobilized surfaces, all cell types adhere well regardless of the surface hydrophobicity. On the other hand, a tri-Arg-immobilized surface exhibits FB-selectivity when the surface is hydrophilic. Additionally, a tri-Ile-immobilized surface exhibits EC-selective cell adhesion when the surface is hydrophobic. We believe that the proposed concept, which is used to investigate the biomolecule-immobilized surface combination, is important to produce new biomaterials, which are highly demanded for medical implants and tissue engineering.

  10. Optimization and characterization of biomolecule immobilization on silicon substrates using (3-aminopropyl)triethoxysilane (APTES) and glutaraldehyde linker

    Energy Technology Data Exchange (ETDEWEB)

    Gunda, Naga Siva Kumar [Department of Mechanical Engineering, University of Alberta, Edmonton, Canada T6G 2G8 (Canada); Singh, Minashree [Department of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Canada T6G 1C9 (Canada); Norman, Lana [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada T6G 2V4 (Canada); Kaur, Kamaljit [Department of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Canada T6G 1C9 (Canada); Mitra, Sushanta K., E-mail: sushanta.mitra@ualberta.ca [Department of Mechanical Engineering, University of Alberta, Edmonton, Canada T6G 2G8 (Canada)

    2014-06-01

    In the present work, we developed and optimized a technique to produce a thin, stable silane layer on silicon substrate in a controlled environment using (3-aminopropyl)triethoxysilane (APTES). The effect of APTES concentration and silanization time on the formation of silane layer is studied using spectroscopic ellipsometry and Fourier transform infrared spectroscopy (FTIR). Biomolecules of interest are immobilized on optimized silane layer formed silicon substrates using glutaraldehyde linker. Surface analytical techniques such as ellipsometry, FTIR, contact angle measurement system, and atomic force microscopy are employed to characterize the bio-chemically modified silicon surfaces at each step of the biomolecule immobilization process. It is observed that a uniform, homogenous and highly dense layer of biomolecules are immobilized with optimized silane layer on the silicon substrate. The developed immobilization method is successfully implemented on different silicon substrates (flat and pillar). Also, different types of biomolecules such as anti-human IgG (rabbit monoclonal to human IgG), Listeria monocytogenes, myoglobin and dengue capture antibodies were successfully immobilized. Further, standard sandwich immunoassay (antibody–antigen–antibody) is employed on respective capture antibody coated silicon substrates. Fluorescence microscopy is used to detect the respective FITC tagged detection antibodies bound to the surface after immunoassay.

  11. Fragmentation study of isolated and nano-solvated biomolecules induced by collision with multiply charged ions and neutral particles

    International Nuclear Information System (INIS)

    This thesis concerns a gas phase study of the fragmentation of bio-molecular systems induced by slow collisions with multiply charged ions (in the keV-region), alkali atoms and rare gases. The main objective was to study the physical processes involved in the dissociation of highly electronically excited systems. In order to elucidate the intrinsic properties of certain biomolecules (porphyrins and amino acids) we have performed experiments in the gas phase with isolated systems. The obtained results demonstrate the high stability of porphyrins after electron removal and attachment. Furthermore, a dependence of the fragmentation pattern produced by multiply charged ions on the isomeric structure of the alanine molecule has been shown. In a second part of the thesis, a strong influence of the environment of the biomolecule on the fragmentation channels, their modification and their new opening, has been clearly proven. This phenomenon occurs in the presence of other surrounding biomolecules (clusters of nucleobases) as well as for molecules of a solvent (molecules of water, methanol and acetonitrile) in which the biomolecule is embedded. In order to extend these studies to larger systems, a new experimental set-up, based on an electro-spray ion source combined with a quadrupole mass filter has been developed. Due to the successful tests and proposed improvements of the device future experiments will become available concerning the fragmentation of large charged and solvated bio-molecular systems induced by collision processes. (author)

  12. Mercury and selenium binding biomolecules in terrestrial mammals (Cervus elaphus and Sus scrofa) from a mercury exposed area.

    Science.gov (United States)

    Ropero, M J Patiño; Fariñas, N Rodríguez; Krupp, E; Mateo, R; Nevado, J J Berzas; Martín-Doimeadios, R C Rodríguez

    2016-06-01

    Mercury (Hg) is likely bound to large biomolecules (e.g. proteins) in living organisms, and in order to assess Hg metabolic pathways and possible toxicological effects, it is essential to study these Hg containing biomolecules. However, the exact nature of most metal binding biomolecules is unknown. Such studies are still in their infancy and information on this topic is scarce because the analysis is challenging, mainly due to their lability upon digestion or extraction from the tissue. New analytical methods that allow complex Hg-biomolecules to be analysed intact are needed and only few very recent studies deal with this approach. Therefore, as an initial step towards the characterization of Hg containing biomolecules, an analytical procedure has been optimised using size-exclusion chromatography (SEC) with inductively coupled plasma mass spectrometry (ICP-MS) detection. We applied this technique to elucidate the distribution and elution profile of Hg and Se, and some physiological important elements such as Fe, Ni, Zn and Cu, to assess metal binding profiles in liver and kidney samples of red deer (Cervus elaphus) and wild boar (Sus scrofa) who roam freely within the largest Hg mining district on Earth, Almadén in Spain. Elemental fractionation profiles of the extracts from different tissues were obtained using two different SEC columns (BioSep-SEC-S2000 GL 300-1kDa and Superdex 75 10/300 GL 70-3kDa). Similar profiles of Hg were observed in red deer and wild boar; however, significant differences were evident for liver and kidney. Moreover, the profiles of Se showed a single peak at high-medium molecular weight in all investigated tissues, while co-elution of Hg with Fe, Ni, Zn and Cu was observed. PMID:27093497

  13. Intracellular delivery of nanomaterials for sub-cellular imaging and tracking of biomolecules

    Science.gov (United States)

    Medepalli, Krishna Kiran

    Nanomaterials have many intriguing applications in biology and medicine. Unique properties such as enhanced electrical properties, increased chemical reactivity and resistance to degradation, novel optical properties and comparable size to that of biological systems have led to their use in various biomedical applications. The most important applications of nanomaterials for medicine are in drug delivery and imaging. This research focuses on utilizing the biocompatibility of single walled Carbon nanotubes (SWCNTs) and optical properties colloidal quantum dots (QDs) for cellular drug delivery and imaging of biomolecules. The first part of this research deals with single walled carbon nanotubes which are excellent candidates for targeted drug delivery applications due their unique structural and functional properties. However, prior to their use in therapeutics, their biocompatibility needs to be thoroughly investigated. The objectives of this research were to establish the biocompatibility of SWCNTs and demonstrate their use as drug delivery carriers into cells. Blood, a living tissue, is chosen as the biological system as it contains various cells which can potentially interact with SWCNTs during the delivery mechanism. The interactions of these cells in the blood (specifically white blood cells or leukocytes) with the SWCNTs provide vital information regarding the immune response of the host to the nanotubes. This research investigates the immune response of white blood cells due to SWCNTs via (a) direct interaction---presence of nanotubes in the blood and, (b) indirect interaction---presentation of nanotubes by antigen-presenting-cells to white blood cells. These two interactions recreate the innate and adaptive immune responses occurring in the body to any foreign substance. SWCNTs are functionalized with single stranded DNA (ss-DNA), which serves as a dispersant of nanotubes as well as a backbone for further attachment of other biomolecules of interest

  14. Perspectivas sobre el desarrollo económico localizado

    Directory of Open Access Journals (Sweden)

    A. H. J. (Bert Helmsing

    2002-09-01

    Full Text Available La creciente movilidad de la producción y de los factores de producción puede haber generado una reversión de la polarización. Sin embargo, el desarrollo económico se localiza crecientemente en aglomeraciones económicas. La globalización es un fenómeno muy localizado. El propósito de este artículo es revisar tres perspectivas parcialmente sobrepuestas sobre el desarrollo económico local. Estas perspectivas corresponden en gran medida a tres factores que refuerzan la naturaleza localizada del desarrollo económico, es decir externalidades, aprendizaje colectivo y gobernabilidad. Las externalidades se refieren a fenómenos conocidos asociados con aglomeración. Más nuevo es el hecho de que constituyen una fuente de retornos crecientes. Se revisará esta nueva escuela de economía geográfica. Al mismo tiempo surgió una nueva geografía económica en base a agrupamientos y distritos industriales. Las externalidades se extienden y cambian de forma. La dinámica del desarrollo económico local puede ser vista desde la perspectiva de la economía evolucionaria. El aprendizaje en general y el aprendizaje colectivo en particular son conceptos centrales a nivel de las empresas y también a nivel de las instituciones territoriales. El aprendizaje aumenta y renueva las competencias locales para formular e implementar políticas económicas. La complejización de las relaciones entre empresas y entre empresas e instituciones territoriales es una fuente importante de sinergias y economías externas pero requiere nuevas formas de gobernabilidad, tanto a nivel industrial como territorialThe growing mobility of production and production factors could have contributed to a polarization reversal. However, it appears that economic development is increasingly localized in economic agglomerations. Globalization is a localized phenomenon. The purpose of this article is to review three partially overlapping perspectives on local economic development

  15. Bacterial toxicity of oxide nanoparticles and their effects on bacterial surface biomolecules

    Science.gov (United States)

    Jiang, Wei

    Toxicity of nano-scaled Al2O3, SiO2, TiO2 and ZnO to bacteria (Bacillus subtilis, Escherichia coli and Pseudomonas fluorescens) was examined and compared to that of their respective bulk (micro-scaled) counterparts. All nanoparticles (NPs) but TiO2 showed higher toxicity than their bulk counterparts. Toxicity of released metal ions was differentiated from that of the oxide particles. ZnO was the most toxic among the three NPs, causing 100% mortality to the three tested bacteria. TEM images showed attachment of NPs to the bacteria, suggesting that the toxicity was affected by bacterial attachment. The effects of oxide NPs on bacteria cells and bacterial surface biomolecules were studied by FTIR spectroscopy to provide a better understanding of their cytotoxicity. Lipopolysaccharide (LPS) and lipoteichoic acid could bind to oxide NPs through hydrogen bonding and ligand exchange, but the cytotoxicity of NPs seemed largely related to the function-involved or structural changes to proteins and phospholipids. The three NPs decreased the intensity ratio of beta-sheets/alpha-helices, indicating protein structure change, which may affect cell physiological activities. The phosphodiester bond of L-alpha-Phosphatidyl-ethanolamine (PE) was broken by ZnO NPs, forming phosphate monoesters and resulting in the highly disordered alkyl chain. Such damage to phospholipid molecular structure may lead to membrane rupture and cell leaking, which is consistent with the fact that ZnO is the most toxic of the three NPs. LPS and PE are amphiphilic biomolecules that are major constituents of the outer membrane of Gram-negative bacteria. Their micelles and vesicles were studied as model cell membranes to evaluate NP effects on membrane construction. The adsorption of polysaccharides on Al2O3 and TiO 2 NPs dispersed LPS vesicles and micelles. LPS coated Al2O 3 NPs, while it caused the aggregation of TiO2 NPs according to atom force microscopy images. Desorption from the two NPs was slow due

  16. On-chip micro-electromagnets for magnetic-based bio-molecules separation

    Energy Technology Data Exchange (ETDEWEB)

    Ramadan, Qasem E-mail: qasem@pmail.ntu.edu.sg; Samper, Victor; Poenar, Daniel; Yu Chen

    2004-10-01

    This paper reports a comprehensive theoretical, finite element and measurement analysis of different designs of planar micro-electromagnets for bio-molecular manipulation. The magnetic field due to current flowing in complex shapes of current-carrying conductors have been calculated analytically, simulated using finite-element analysis (FEA), and measured using the superconducting quantum interference device technique (SQUID). A comparison of the theoretical and measured magnetic field strength and patterns is presented. The planar electromagnets have been fabricated using patterned Al 2 {mu}m thick. The aim of the study is to explore and optimize the geometrical and structural parameters of planar electromagnets that give rise to the highest magnetic fields and forces for magnetic micro-beads manipulation. Magnetic beads are often used in biochemical assays for separation of bio-molecules. Typical beads are 0.2-10 {mu}m in diameter and have superparamagnetic properties. Increasing the intensity of the magnetic field generated by a coil by injection a larger current is not the most suitable solution as the maximum current is limited by Joule heating. Consequently, in order to maximize the field for a given current, one should optimize the geometry of the coil, as this is an extremely significant factor in determining the magnetic field intensity in 2D planar designs. The theoretical and measured results of this work show that the meander micro-electromagnet with mesh-shaped winding profile produces the strongest magnetic field (about 2.7 {mu}T for a current intensity of 6 mA) compared with other meander designs, such as the serpentine and rosette-shaped ones. The magnetic fields of these three types of meander-shaped micro-electromagnets were compared theoretically with that produced by a spiral micro-electromagnet whose technological realization is more complicated and costly due to the fact that it requires an additional insulation layer with a contact window and

  17. Theoretical and experimental proof of the accumulating transfer of tritium from water into DNA and other biomolecules in vitro and in vivo

    International Nuclear Information System (INIS)

    Heisenberg's Uncertainity Relation leads to the conclusion, tritium accumulates in the exchangeable hydrogen positions of biomolecules if it is administered in the state of water. Appropriate tests of fishsperm DNA and the biomolecules of piglet's liver resulted in a fractionation factor of about 2 favouring such organically bound tritium. Furthermore, a fractionation factor of 1.4 is found in the hydration sheet of the biomolecules. The logistic growth analysis of maize and barley confirms the accumulation of tritium from water in the tissue solids of the plants. (orig.)

  18. La Ha de la infancia en Italia. Problemas y perspectiva

    Directory of Open Access Journals (Sweden)

    Enzo CATARSI

    2010-03-01

    Full Text Available RESUMEN: La historiografía italiana de la infancia, como la de otros muchos países europeos, está hoy embarcada en una tarea de desarrollo y profundización que permitirá recuperar los retrasos que la han caracterizado. En efecto, también en Italia la historia de la infancia y su individuación como «objeto» historiografía constituyen una adquisición reciente, lograda con la ayuda de diversas influencias. La primera, estrechamente vinculada a la historia de las mentalidades, representada por la obra de Ph. Aries, «El niño y la vida familiar en el Antiguo Régimen», traducido al italiano en 1968. La segunda es la historia social, orientada al estudio de los diversos aspectos de la vida de una sociedad, y más atenta a sus acontecimientos. La tercera la representa el estructuralismo, especialmente el francés, y en concreto M. Foucault. La particular influencia que, también en el contexto italiano, han alcanzado los trabajos de Ph. Aries y L. DeMause, muy importantes por haber abierto una línea de investigación, aunque con las obligadas diferencias, ha conducido a privilegiar una perspectiva exclusiva de historia de las mentalidades que se muestra muy ambigua y claramente interpretativa en exceso.

  19. Lectura de la mente Una perspectiva neurofilosófica

    Directory of Open Access Journals (Sweden)

    Kathinka Evers

    2013-04-01

    Full Text Available Hasta ahora, el acceso a otras mentes presuponía las expresiones y narraciones de los individuos. En la actualidad, se han desarrollado varios métodos que pueden medir los estados cerebrales relevantes para valorar las facultades mentales sin que se manifieste en 1ª persona habla o comportamiento externo alguno. La resonancia magnética funcional y el condicionamiento de huella se emplean fuera del ámbito clínico para acceder a la conciencia subjetiva; se utilizan clínicamente para identificar patrones de actividad en el cerebro que sugieran la presencia de conciencia en personas que sufren trastornos graves de conciencia y métodos para comunicarse cerebralmente con pacientes con incapacidad motora para comunicarse. En este capítulo, examinamos las posibilidades y los límites del acceso a otras mentes mediante interfaces cerebro-máquina. Exponemos que estas técnicas auguran importantes avances médicos y abren nuevas perspectivas de comunicación y para entender la conciencia, sin embargo, también plantean preocupaciones éticas, en especial el uso incorrecto como consecuencia de las expectativas creadas y las malas interpretaciones.

  20. perspectiva da antropologia pós-moderna

    Directory of Open Access Journals (Sweden)

    Mara Ambrosina de Oliveira Vargas

    2007-01-01

    Full Text Available Basado en la perspectiva teórica de la Antropología Posmoderna, el presente artículo discute una de las maneras posibles de narrar la historia del yo en el mundo contemporáneo, demarcando el impacto de la saturación social en la forma de cómo se conceptúa el(los yo(s, con inferencia en los “diferentes procesos” del vivir humano. De este modo, el análisis busca considerar la noción de que la formación de los más diferentes grupos está cruzada por un ideal regulador del yo, en sus formas de experiencia de vida. Cuestiona también la búsqueda por la verdad del sujeto en visiones totales, comprendiendo que somos y vivimos dentro de narrativas construidas a muchas manos, y, que tal supuesto, abre muchas posibilidades teóricas en el abordaje de antiguos y nuevos temas que interesan a los profesionales de la salud, para los cuales se consolidan nuevas relaciones entre las ciencias de la salud, las ciencias humanas y las ciencias sociales.

  1. Perspectivas da profissão contábil

    Directory of Open Access Journals (Sweden)

    Nivaldo João dos Santos

    2002-11-01

    Full Text Available As perspectivas profissionais na área contábil são muito promissoras. É natural que estudantes demonstrem apreensão acerca da carreira que advirá após a conclusão do curso de graduação em ciências contábeis, pois trata-se de investimento elevado - envolvendo muito tempo e dinheiro. De tempos em tempos leigos anunciam a extinção da atividade contábil, sem nenhum fundamento. A atividade contábil é das que mais evolui e sua essencialidade se revela com mais força quando são descobertas fraudes contábeis e novos artifícios ilícitos visando iludir acionistas e investidores. Apesar do grande contingente de pessoas que conclui cursos na área, muitas novas empresas são constituídas, outras formas de sociedades são desenvolvidas, todas necessitando de serviços de profissionais contabilistas. O grande desafio da classe contábil consiste no contínuo aperfeiçoamento e na consolidação do elevado nível intelectual que o mercado globalizado requisita.

  2. La muerte como proceso: una perspectiva antropológica

    Directory of Open Access Journals (Sweden)

    Bárbara Martínez

    2013-09-01

    Full Text Available Este artículo, desde una perspectiva antropológica, combina recientes aproximaciones que cuestionan la homología entre muerte y deceso biológico, con la tradición de estudios que revisan los rituales de muerte en el área geográfica andina. En particular, examina cómo se produce en El Cajón, Catamarca, noroeste argentino, la incorporación de un fallecido al esquema cosmológico, y cómo la muerte, que es un puntapié inicial para ello ocurra, no es meramente un evento biológico sino también un proceso social de gran dinamismo. A partir del trabajo de campo etnográfico, y tomando como herramientas metodológicas entrevistas abiertas de sesiones múltiples y observación participante, presenta una propuesta analítica que procura superar la homología entre muerte y deceso biológico, sugiriendo una noción que incluye la dimensión orgánica, pero también la social: el proceso de la muerte.

  3. Perspectivas da agricultura sustentável no Brasil

    Directory of Open Access Journals (Sweden)

    Rosângela Ap. de Medeiros Hespanhol

    2008-03-01

    -technological development as the only road capable to solve the derived problems of the shortage of foods and the exhaustion of the natural resources; and those that are opposed to this perspective. They propose more maintainable forms, which could be joined under the Alternative Agriculture denomination. It was also tried to discuss the challenges and the perspectives that come in terms of viability terms to discuss and of expansion of the maintainable production systems in environmental and social terms in the agriculture of small scale in Brazil, to example of the organic production.  O processo de incorporação tecnológica ocorrida na agricultura ao longo da história e, mais precisamente, a difusão do pacote da Revolução Verde após a Segunda Guerra Mundial produziu várias implicações sócio-ambientais. Com o agravamento desses problemas em escala mundial e, sobretudo em países como o Brasil, houve a incorporação, ainda limitada, de preocupações ambientais em relação à agricultura. Essa mudança fomentou a discussão e levou à formulação de perspectivas de análise e de intervenção antagônicas e conflitantes entre si, refletindo diferentes interesses e posicionamentos sobre os modelos de desenvolvimento dos países e sobre a própria sustentabilidade. Nesse sentido, procurou-se identificar duas destas perspectivas no Brasil: a que ainda concebe o desenvolvimento científico-tecnológico como a única via capaz de resolver os problemas derivados da escassez de alimentos e do esgotamento dos recursos naturais; e aquelas que se opõem a esta perspectiva e propõem formas mais sustentáveis, que poderiam ser agrupadas sob a denominação de Agricultura Alternativa. Procurou também discutir os desafios e as perspectivas que se apresentam em termos de viabilidade e de expansão dos sistemas de produção sustentáveis em termos ambientais e sociais na agricultura de pequena escala no Brasil, a exemplo da produção orgânica.

  4. Perspectivas psicossociais para o estudo do cotidiano de trabalho

    Directory of Open Access Journals (Sweden)

    Fábio de Oliveira

    2014-04-01

    Full Text Available Este estudo teve por objetivo analisar o debate e o aprofundamento teórico e metodológico desenvolvido nos estudos sobre a vida cotidiana no trabalho. A investigação partiu do diálogo interdisciplinar entre a antropologia do trabalho, a ergologia e a psicologia social do trabalho e sistematizou as contribuições mútuas entre esses campos científicos, suas aproximações e seus afastamentos da tematização e da apropriação da atividade humana no trabalho sob a perspectiva do cotidiano. A análise comparativa destacou eixos que diferenciam as formas de aproximação ao objeto, que se referem às relações estabelecidas entre saberes práticos e técnico-científicos e aos modos de intervenção sobre as situações de trabalho. As abordagens comparativas compartilham o interesse em conhecer o trabalho real, o valor conferido aos conhecimentos dos trabalhadores e a sensibilidade às dimensões micropolíticas do cotidiano. Conclui-se que a localização em cada um desses eixos depende da maior ou menor filiação às tradições da antropologia ou da ergonomia.

  5. Observation of adsorption behavior of biomolecules on ferroelectric crystal surfaces with polarization domain patterns

    Science.gov (United States)

    Nakayama, Tomoaki; Isobe, Akiko; Ogino, Toshio

    2016-08-01

    Lithium tantalate (LiTaO3) is one of the ferroelectric crystals that exhibit spontaneous polarization domain patterns on its surface. We observed the polarization-dependent adsorption of avidin molecules, which are positively charged in a buffer solution at pH 7.0, on LiTaO3 surfaces caused by electrostatic interaction at an electrostatic double layer using atomic force microscopy (AFM). Avidin adsorption in the buffer solution was confirmed by scratching the substrate surfaces using the AFM cantilever, and the adsorption patterns were found to depend on the avidin concentration. When KCl was added to the buffer solution to weaken the electrostatic double layer interaction between avidin molecules and LiTaO3 surfaces, adsorption domain patterns disappeared. From the comparison between the adsorption and chemically etched domain patterns, it was found that avidin molecule adsorption is enhanced on negatively polarized domains, indicating that surface polarization should be taken into account in observing biomolecule behaviors on ferroelectric crystals.

  6. Label-free Raman mapping of surface distribution of protein a and IgG biomolecules.

    Science.gov (United States)

    Combs, Zachary A; Chang, Sehoon; Clark, Tolecia; Singamaneni, Srikanth; Anderson, Kyle D; Tsukruk, Vladimir V

    2011-03-15

    We have demonstrated a nanoengineered substrate composed of micropatterned silver nanoparticles to be used for the label-free mapping of adsorbed biomolecules. We utilized surface-enhanced Raman scattering (SERS) phenomenon to monitor the known bioanalytes, protein A and human immunoglobulin G (IgG). The SERS substrate was composed of a poly(alylamine hydrochloride) (PAH)/poly(styrenesulfonate) (PSS) layer-by-layer (LbL) nanocoating micropatterned with silver nanoparticles confined to microscopic stripes. Selective adsorption of biomacromolecules is facilitated by the amine-terminated LbL nanocoating, which prevents the surface adsorption of positively charged protein A across the surface except on the patterned regions containing negatively charged silver nanoparticles. Furthermore, adsorption of IgG on predetermined regions is facilitated by the selective binding of the Fc region of IgG to protein A. This label-free SERS approach provides accurate, selective, and fast detection of protein A and IgG solutions with a nanomolar concentration, down to below 1 nM for IgG in solution. This method could also be utilized for the facile detection of proteins in field conditions as well as in clinical, forensic, industrial, and environmental laboratories. PMID:21294559

  7. Systematic Errors Associated with the CPMG Pulse Sequence and Their Effect on Motional Analysis of Biomolecules

    Science.gov (United States)

    Ross, A.; Czisch, M.; King, G. C.

    1997-02-01

    A theoretical approach to calculate the time evolution of magnetization during a CPMG pulse sequence of arbitrary parameter settings is developed and verified by experiment. The analysis reveals that off-resonance effects can cause systematic reductions in measured peak amplitudes that commonly lie in the range 5-25%, reaching 50% in unfavorable circumstances. These errors, which are finely dependent upon frequency offset and CPMG parameter settings, are subsequently transferred into erroneousT2values obtained by curve fitting, where they are reduced or amplified depending upon the magnitude of the relaxation time. Subsequent transfer to Lipari-Szabo model analysis can produce significant errors in derived motional parameters, with τeinternal correlation times being affected somewhat more thanS2order parameters. A hazard of this off-resonance phenomenon is its oscillatory nature, so that strongly affected and unaffected signals can be found at various frequencies within a CPMG spectrum. Methods for the reduction of the systematic error are discussed. Relaxation studies on biomolecules, especially at high field strengths, should take account of potential off-resonance contributions.

  8. AFNMR: automated fragmentation quantum mechanical calculation of NMR chemical shifts for biomolecules

    International Nuclear Information System (INIS)

    We evaluate the performance of the automated fragmentation quantum mechanics/molecular mechanics approach (AF-QM/MM) on the calculation of protein and nucleic acid NMR chemical shifts. The AF-QM/MM approach models solvent effects implicitly through a set of surface charges computed using the Poisson–Boltzmann equation, and it can also be combined with an explicit solvent model through the placement of water molecules in the first solvation shell around the solute; the latter substantially improves the accuracy of chemical shift prediction of protons involved in hydrogen bonding with solvent. We also compare the performance of AF-QM/MM on proteins and nucleic acids with two leading empirical chemical shift prediction programs SHIFTS and SHIFTX2. Although the empirical programs outperform AF-QM/MM in predicting chemical shifts, the differences are in some cases small, and the latter can be applied to chemical shifts on biomolecules which are outside the training set employed by the empirical programs, such as structures containing ligands, metal centers, and non-standard residues. The AF-QM/MM described here is implemented in version 5 of the SHIFTS software, and is fully automated, so that only a structure in PDB format is required as input

  9. Conductive Paper with Antibody-Like Film for Electrical Readings of Biomolecules

    Science.gov (United States)

    Tavares, Ana P. M.; Ferreira, Nádia S.; Truta, Liliana A. A. N. A.; Sales, M. Goreti F.

    2016-01-01

    This work reports a novel way of producing an inexpensive substrate support to assemble a sensing film, designed for the electrical transduction of an intended biomolecule. The support uses cellulose paper as substrate, made hydrophobic with solid wax and covered by a home-made conductive ink having graphite as core material. The hydrophobicity of the paper was confirmed by contact angle measurements and the conductive ink composition was optimized with regard to its adhesion, conductivity, and thermal stability. This support was further modified targeting its application in quantitative analysis. Carnitine (CRT) was selected as target compound, a cancer biomarker. The recognition material consisted of an antibody-like receptor film for CRT, tailored on the support and prepared by electrically-sustained polymerization of 3,4-ethylenedioxythiophene (EDOT) or dodecylbenzenesulfonic acid (DBS). Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy analysis confirmed the presence of the polymeric film on the support, and the performance of the devices was extensively evaluated with regard to linear response ranges, selectivity, applicability, and reusability. Overall, the paper-based sensors offer simplicity of fabrication, low cost and excellent reusability features. The design could also be extended to other applications in electrical-based approaches to be used in point-of-care (POC). PMID:27210055

  10. A treecode-accelerated boundary integral Poisson-Boltzmann solver for electrostatics of solvated biomolecules

    Science.gov (United States)

    Geng, Weihua; Krasny, Robert

    2013-08-01

    We present a treecode-accelerated boundary integral (TABI) solver for electrostatics of solvated biomolecules described by the linear Poisson-Boltzmann equation. The method employs a well-conditioned boundary integral formulation for the electrostatic potential and its normal derivative on the molecular surface. The surface is triangulated and the integral equations are discretized by centroid collocation. The linear system is solved by GMRES iteration and the matrix-vector product is carried out by a Cartesian treecode which reduces the cost from O(N2) to O(NlogN), where N is the number of faces in the triangulation. The TABI solver is applied to compute the electrostatic solvation energy in two cases, the Kirkwood sphere and a solvated protein. We present the error, CPU time, and memory usage, and compare results for the Poisson-Boltzmann and Poisson equations. We show that the treecode approximation error can be made smaller than the discretization error, and we compare two versions of the treecode, one with uniform clusters and one with non-uniform clusters adapted to the molecular surface. For the protein test case, we compare TABI results with those obtained using the grid-based APBS code, and we also present parallel TABI simulations using up to eight processors. We find that the TABI solver exhibits good serial and parallel performance combined with relatively simple implementation, efficient memory usage, and geometric adaptability.

  11. Optimization of biomolecule separation by combining microscale filtration and design-of-experiment methods.

    Science.gov (United States)

    Kazemi, Amir S; Kawka, Karina; Latulippe, David R

    2016-10-01

    There is considerable interest in developing microscale (i.e., high-throughput) methods that enable multiple filtration experiments to be run in parallel with smaller sample amounts and thus reduce the overall required time and associated cost to run the filtration tests. Previous studies to date have focused on simply evaluating the filtration capacity, not the separation performance. In this work, the stirred-well filtration (SWF) method was used in combination with design-of-experiment (DOE) methods to optimize the separation performance for three binary mixtures of bio-molecules: protein-protein, protein-polysaccharide, and protein-DNA. Using the parallel based format of the SWF method, eight constant-flux ultrafiltration experiments were conducted at once to study the effects of stirring conditions, permeate flux, and/or solution conditions (pH, ionic strength). Four separate filtration tests were conducted for each combination of process variables; in total, over 100 separate tests were conducted. The sieving coefficient and selectivity results are presented to match the DOE design format and enable a greater understanding of the effects of the different process variables that were studied. The method described herein can be used to rapidly determine the optimal combination of process factors that give the best separation performance for a range of membrane-based separations applications and thus obviate the need to run a large number of traditional lab-scale tests. Biotechnol. Bioeng. 2016;113: 2131-2139. © 2016 Wiley Periodicals, Inc. PMID:27563852

  12. Conductive Paper with Antibody-Like Film for Electrical Readings of Biomolecules

    Science.gov (United States)

    Tavares, Ana P. M.; Ferreira, Nádia S.; Truta, Liliana A. A. N. A.; Sales, M. Goreti F.

    2016-05-01

    This work reports a novel way of producing an inexpensive substrate support to assemble a sensing film, designed for the electrical transduction of an intended biomolecule. The support uses cellulose paper as substrate, made hydrophobic with solid wax and covered by a home-made conductive ink having graphite as core material. The hydrophobicity of the paper was confirmed by contact angle measurements and the conductive ink composition was optimized with regard to its adhesion, conductivity, and thermal stability. This support was further modified targeting its application in quantitative analysis. Carnitine (CRT) was selected as target compound, a cancer biomarker. The recognition material consisted of an antibody-like receptor film for CRT, tailored on the support and prepared by electrically-sustained polymerization of 3,4-ethylenedioxythiophene (EDOT) or dodecylbenzenesulfonic acid (DBS). Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy analysis confirmed the presence of the polymeric film on the support, and the performance of the devices was extensively evaluated with regard to linear response ranges, selectivity, applicability, and reusability. Overall, the paper-based sensors offer simplicity of fabrication, low cost and excellent reusability features. The design could also be extended to other applications in electrical-based approaches to be used in point-of-care (POC).

  13. Excitation and ionic fragmentation of gas-phase biomolecules using electrons and synchrotron radiation

    Science.gov (United States)

    de Souza, G. G. B.; Coutinho, L. H.; Nunez, C.; Bernini, R.; Castilho, R. B.; Lago, A. F.

    2007-11-01

    An experimental study of the electronic excitation and ionic dissociation of two important classes of biomolecules-natural products (biogenic volatile organic compounds, VOCs, and volatile components of essential oils) and DNA and RNA constituents (aminoacids and bases) is here exemplified with recent results on the fragmentation of thymine and isoprene as induced by synchrotron radiation and fast electrons. Fragmentation of the thymine molecule was seen to dramatically increase as the photon energy increased from 21 to 300 eV and 450 eV. At the highest photon energy, simply and doubly charged N and O atoms were observed. The parent ion (m/z = 126) could be observed at all photon energies. The fragmentation pattern observed in the 1.0 keV electron impact mass spectrum of thymine resembled more closely the fragmentation observed with 21 eV photons. In isoprene, the dominant fragments observed at 21 eV and 310 eV photon energy as well as in the 1.0 keV electron impact mass spectrum were C5H7+(m/z = 67), C4H5+(m/z = 53), C3H3+(m/z = 39) and C2H3+(m/z = 27). Previously unreported fragments, namely H+, C+, CH+, CH2+, and CH3+ were observed at the high photon energies and at the electron impact mass spectrum.

  14. Prototype sphere-on-sphere silica particles for the separation of large biomolecules.

    Science.gov (United States)

    Fekete, Szabolcs; Rodriguez-Aller, Marta; Cusumano, Alessandra; Hayes, Richard; Zhang, Haifei; Edge, Tony; Veuthey, Jean-Luc; Guillarme, Davy

    2016-01-29

    The goal of this study was to evaluate the possibilities offered by a prototype HPLC column packed with ∼2.5μm narrow size distribution sphere-on-sphere (SOS) silica particles bonded with C4 alkyl chains, for the analytical characterization of large biomolecules. The kinetic performance of this material was evaluated in both isocratic and gradient modes using various model analytes. The data were compared to those obtained on other widepore state-of-the-art fully core-shell and fully porous materials commonly employed to separate proteins moreover to a reference 5μm wide pore material that is still often used in QC labs. In isocratic mode, minimum reduced plate height values of hmin=2.6, 3.3 and 3.3 were observed on butylparaben, decapeptide and glucagon, respectively. In gradient elution mode, the SOS column performs very high efficiency when working with fast gradients. This prototype column was also comparable (and sometimes superior) to other widepore stationary phases, whatever the gradient time and flow rate, when analyzing the largest model protein, namely BSA. These benefits may be attributed to the SOS particle morphology, minimizing the intra-particle mass transfer resistance. Finally, the SOS column was also applied for the analytical characterization of commercial monoclonal antibody (mAb) and antibody-drug conjugate (ADC) samples. With these classes of proteins, the performance of SOS column was similar to the best widepore stationary phases available on the market. PMID:26755414

  15. N-acetyl-l-histidine, a Prominent Biomolecule in Brain and Eye of Poikilothermic Vertebrates

    Science.gov (United States)

    Baslow, Morris H.; Guilfoyle, David N.

    2015-01-01

    N-acetyl-l-histidine (NAH) is a prominent biomolecule in brain, retina and lens of poikilothermic vertebrates. In fish lens, NAH exhibits an unusual compartmentalized metabolism. It is synthesized from l-histidine (His) and acetyl Co-enzyme A. However, NAH cannot be catabolized by lens cells. For its hydrolysis, NAH is exported to ocular fluid where a specific acylase cleaves His which is then actively taken up by lens and re-synthesized into NAH. This energy-dependent cycling suggested a pump mechanism operating at the lens/ocular fluid interface. Additional studies led to the hypothesis that NAH functioned as a molecular water pump (MWP) to maintain a highly dehydrated lens and avoid cataract formation. In this process, each NAH molecule released to ocular fluid down its gradient carries with it 33 molecules of bound water, effectively transporting the water against a water gradient. In ocular fluid the bound water is released for removal from the eye by the action of NAH acylase. In this paper, we demonstrate for the first time the identification of NAH in fish brain using proton magnetic resonance spectroscopy (MRS) and describe recent evidence supporting the NAH MWP hypothesis. Using MRS, we also document a phylogenetic transition in brain metabolism between poikilothermic and homeothermic vertebrates. PMID:25919898

  16. Carbon Nanofiber Arrays: A Novel Tool for Microdelivery of Biomolecules to Plants

    Science.gov (United States)

    Davern, Sandra M.; McKnight, Timothy E.; Morrell-Falvey, Jennifer L.; Shpak, Elena D.; Kalluri, Udaya C.; Jelenska, Joanna; Greenberg, Jean T.; Mirzadeh, Saed

    2016-01-01

    Effective methods for delivering bioprobes into the cells of intact plants are essential for investigating diverse biological processes. Increasing research on trees, such as Populus spp., for bioenergy applications is driving the need for techniques that work well with tree species. This report introduces vertically aligned carbon nanofiber (VACNF) arrays as a new tool for microdelivery of labeled molecules to Populus leaf tissue and whole plants. We demonstrated that VACNFs penetrate the leaf surface to deliver sub-microliter quantities of solution containing fluorescent or radiolabeled molecules into Populus leaf cells. Importantly, VACNFs proved to be gentler than abrasion with carborundum, a common way to introduce material into leaves. Unlike carborundum, VACNFs did not disrupt cell or tissue integrity, nor did they induce production of hydrogen peroxide, a typical wound response. We show that femtomole to picomole quantities of labeled molecules (fluorescent dyes, small proteins and dextran), ranging from 0.5–500 kDa, can be introduced by VACNFs, and we demonstrate the use of the approach to track delivered probes from their site of introduction on the leaf to distal plant regions. VACNF arrays thus offer an attractive microdelivery method for the introduction of biomolecules and other probes into trees and potentially other types of plants. PMID:27119338

  17. Concentration methods for high-resolution THz spectroscopy of nucleic-acid biomolecules and crystals

    Science.gov (United States)

    Brown, E. R.; Zhang, W.; Mendoza, E. A.; Kuznetsova, Y.; Brueck, S. R. J.; Rahman, M.; Norton, M. L.

    2012-03-01

    Biomolecules can exhibit low-lying vibrational modes in the THz region which are detectable in transmission given a strong molecular dipole moment and optical depth, and a spectrometer of adequate sensitivity. The nucleic acids are particularly interesting because of applications such as label-free gene assay, bio-agent detection, etc. However for nucleic acids, sample preparation and THz coupling are of paramount importance because of the strong absorption by liquid water and the small concentration of molecules present in physiological solutions. Concentration methods become necessary to make the THz vibrational modes detectable, either by concentrating the nucleic-acid sample itself in a small volume but large area, or by concentrating the THz radiation down to the volume of the sample. This paper summarizes one type of the first method: nanofluidic channel arrays for biological nucleic acids; and two types of the second method: (1) a circular-waveguide pinhole, and (2) a circular-waveguide, conical-horn coupling structure, both for DNA crystals. The first method has been demonstrated on a very short artificial nucleic acid [small-interfering (si) RNA (17-to-25 bp)] and a much longer, biological molecule [Lambda-phage DNA (48.5 kbp)]. The second method has been demonstrated on small (~100 micron) single crystals of DNA grown by the sitting-drop method.

  18. Probes for biomolecules detection based on RET-enhanced fluorescence polarization.

    Science.gov (United States)

    Ren, Dahai; Wang, Jun; Wang, Bin; You, Zheng

    2016-05-15

    Fluorescent probes based on the principle of resonance energy transfer (RET) or the principle of fluorescence polarization (FP) are already used to detect biomolecules independently. However, there were no in-depth studies about the impact of RET on FP. Also, very few studies gave a comprehensive analysis on how to effectively design such a fluorescent probe. Based on the principle of resonance energy transfer (RET), we constructed fluorescent probes (SA-488-sub-nanogold) using streptavidin labeled Alexa488 (SA-488), nanogold and biotinylated substrate peptide (biotin-subpeptide). The influence of the structure and the ingredients of the substrate peptide were discussed. After SA-488 was combined with the biotin-subpeptide and the nanogold, its fluorescence intensity (FI) would be suppressed due to the energy transfer, leading to an increase in its volume and mass. The suppression of the FI led to a decrease in SA-488's effective concentration, and the increase in the volume or mass prolonged the SA-488's rotational relaxation time. Both changes increased SA-488's polarization in the solution. Therefore, the FP performance of the probe is enhanced by the RET. Using the probe, trypsin and biotin were detected by the change in both fluorescence intensity and fluorescence polarization, showing higher reliability, higher sensitivity, and a lower detection limit. PMID:26774994

  19. Biomolecule-Mineral Interactions in the Geochemical Environment on Early Earth and in the Human Body

    Science.gov (United States)

    Sahai, N.

    2011-12-01

    We worked on four projects consistent with the broad goals of the grant to investigate (i) the potential impacts of mineral surface chemistry and particle size on the stability and viability of cell membranes, bacteria and human cells and (ii) the influence of biomolecules on mineral nucleation and growth. The projects are of relevance to the origin and early evolution of life, biomineralization, medical mineralogy, and environmental biogeochemistry. The freedom enabled by the five-year grant to explore high-risk scientific areas, and the resulting high impact outcomes, cannot be overstated. We developed an almost entirely new field of Medical Mineralogyy and extended our concepts and knowledge-base to the potential roles of mineral surfaces in the evolution of protocells and the earliest cells. These exciting connections to medical mineralogy, and to the origin and evolution of life on early Earth are fascinating topics to the general public and even to other scientists, especially when the links to mineralogy and geochemistry are highlighted. In brief, we examined the stability of lipid bilayers representing model protocell membranes comprised of phospholipid bilayers with mineral surfaces. We found that the stability of lipid bilayers depends on mineral surface charge and increases as silica glass ~ quartz Annual Meeting.

  20. Experimental detection of long-distance interactions between biomolecules through their diffusion behavior: Numerical study

    Science.gov (United States)

    Nardecchia, Ilaria; Spinelli, Lionel; Preto, Jordane; Gori, Matteo; Floriani, Elena; Jaeger, Sebastien; Ferrier, Pierre; Pettini, Marco

    2014-08-01

    The dynamical properties and diffusive behavior of a collection of mutually interacting particles are numerically investigated for two types of long-range interparticle interactions: Coulomb-electrostatic and dipole-electrodynamic. It is shown that when the particles are uniformly distributed throughout the accessible space, the self-diffusion coefficient is always lowered by the considered interparticle interactions, irrespective of their attractive or repulsive character. This fact is also confirmed by a simple model to compute the correction to the Brownian diffusion coefficient due to the interactions among the particles. These interactions are also responsible for the onset of dynamical chaos and an associated chaotic diffusion which still follows an Einstein-Fick-like law for the mean-square displacement as a function of time. Transitional phenomena are observed for Coulomb-electrostatic (repulsive) and dipole-electrodynamic (attractive) interactions considered both separately and in competition. The outcomes reported in this paper clearly indicate a feasible experimental method to probe the activation of resonant electrodynamic interactions among biomolecules.

  1. Photoemission study of metallic iron nanoparticles surface aging in biological fluids. Influence on biomolecules adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Canivet, L.; Denayer, F.O. [Université de Lille 2, Droit et Santé, 42 rue P. Duez, 59000 Lille (France); Champion, Y.; Cenedese, P. [CNRS-ICMPE, 2 rue H. Dunant, 94320 Thiais (France); Dubot, P., E-mail: pdubot@icmpe.cnrs.fr [CNRS-ICMPE, 2 rue H. Dunant, 94320 Thiais (France)

    2014-07-01

    Iron nanoparticles (nFe) prepared by vaporization and cryogenic condensation process (10–100 nm) has been exposed to Hank's balanced salt solution (HBSS) and the B-Ali cell growth fluids. These media can be used for cellular growth to study nFe penetration through cell membrane and its induced cytotoxicity. Surface chemistry of nFe exposed to such complex fluids has been characterized as the nanoparticles surface can be strongly changed by adsorption or corrosion processes before reaching intracellular medium. Particle size and surface chemistry have been characterized by scanning electron microscopy (SEM) and high-resolution X-ray photoelectron spectroscopy (HR-XPS). Exposition of nFe particles to growth and differentiation media leads to the formation of an oxy-hydroxide layer containing chlorinated species. We found that the passivated Fe{sub 2}O{sub 3} layer of the bare nFe particles is rapidly transformed into a thicker oxy-hydroxide layer that has a greater ability to adsorb molecular ions or ionic biomolecules like proteins or DNA.

  2. Physics and capabilities of terahertz spectroscopy to study the water-biomolecule interaction

    Science.gov (United States)

    Vezzoli, G. C.

    2007-09-01

    We have conducted the first study of the use of terahertz radiation to precisely identify pre-melting, melting, polymerization, depolymerization and the influence of polar water in sulfur by scanning frequency as a parametric function of temperature, and including identifying precursor and intermediate states. This spectroscopic study has also identified the orthorhombic-monoclinic phase transformation, and the melting of the superheated orthorhombic phase. This work also reports detection of a water absorption indicating a perturbation of the water molecules, associated with solvation spheres of the inter-chain dynamics, as a precursor to a transition, and supporting our earlier results showing the transducing capabilities of conglomerates of water molecules. Through a study of the fine structure of the water absorption, we are able to determine information about local polarization effects which contribute to the transducing properties of water relative to a ligand. The above inorganic polymer study is applied to the understanding of the response of biomolecules to thermal and chemical influences, and data are included giving optical, electrical, and pH properties of the DNA-water system, showing a major conformational transition at ~43°C, and various forms of reconformation of DNA macromolecule due to chemical perturbation. Our results include findings aimed at complementing existing inhibitors that are intended to prevent retrovirus/phage invasion of the host cell DNA.

  3. Surface reactivity of rapidly quenched nano-quasicrystalline ribbons with respect to biomolecules

    International Nuclear Information System (INIS)

    In this paper, we report on preliminary investigations about surface reactivity of quasicrystalline-based alloys with respect to small biological molecules such as amino-acids. The main purpose is to study potential applications for these materials in biomedical fields since biomolecules are well known to be sensitive to solid surface wettability, surface energy and charge. In that sense, quasicrystals surfaces could be attractive considering their unusual symmetry, their low surface energy and their peculiar electronic properties. Our investigations were focussed on superficial reactivity of as-quenched Ti45Zr38Ni17 (numbers indicate at.%) ribbons, whose microstructure was analysed by transmission electron microscopy and X-ray diffraction. Surfaces were then carefully polished and immersed in a solution (C = 10-2 mol l-1, pH 6) of L-glutamic acid or L-lysine for duration varying from 30 min to 6 days. Molecular vibrational modes and adsorption kinetics were investigated using infrared spectroscopy. The first results reveal that L-glutamic acid seems to display faster adsorption kinetic on quasicrystalline ribbons compared to that on pure titanium (cpTi) or on β-metastable alloys (Ti-12 Mo-6 Zr-4.5 Sn), which is quite interesting since surface energy on quasicrystals is known to be low

  4. Microfluidic paper-based biomolecule preconcentrator based on ion concentration polarization.

    Science.gov (United States)

    Han, Sung Il; Hwang, Kyo Seon; Kwak, Rhokyun; Lee, Jeong Hoon

    2016-06-21

    Microfluidic paper-based analytical devices (μPADs) for molecular detection have great potential in the field of point-of-care diagnostics. Currently, a critical problem being faced by μPADs is improving their detection sensitivity. Various preconcentration processes have been developed, but they still have complicated structures and fabrication processes to integrate into μPADs. To address this issue, we have developed a novel paper-based preconcentrator utilizing ion concentration polarization (ICP) with minimal addition on lateral-flow paper. The cation selective membrane (i.e., Nafion) is patterned on adhesive tape, and this tape is then attached to paper-based channels. When an electric field is applied across the Nafion, ICP is initiated to preconcentrate the biomolecules in the paper channel. Departing from previous paper-based preconcentrators, we maintain steady lateral fluid flow with the separated Nafion layer; as a result, fluorescent dyes and proteins (FITC-albumin and bovine serum albumin) are continuously delivered to the preconcentration zone, achieving high preconcentration performance up to 1000-fold. In addition, we demonstrate that the Nafion-patterned tape can be integrated with various geometries (multiplexed preconcentrator) and platforms (string and polymer microfluidic channel). This work would facilitate integration of various ICP devices, including preconcentrators, pH/concentration modulators, and micro mixers, with steady lateral flows in paper-based platforms. PMID:27199301

  5. A Universal Method for Fishing Target Proteins from Mixtures of Biomolecules using Isothermal Titration Calorimetry

    International Nuclear Information System (INIS)

    The most challenging tasks in biology include the identification of (1) the orphan receptor for a ligand, (2) the ligand for an orphan receptor protein, and (3) the target protein(s) for a given drug or a lead compound that are critical for the pharmacological or side effects. At present, several approaches are available, including cell- or animal-based assays, affinity labeling, solid-phase binding assays, surface plasmon resonance, and nuclear magnetic resonance. Most of these techniques are not easy to apply when the target protein is unknown and the compound is not amenable to labeling, chemical modification, or immobilization. Here we demonstrate a new universal method for fishing orphan target proteins from a complex mixture of biomolecules using isothermal titration calorimetry (ITC) as a tracking tool. We took snake venom, a crude mixture of several hundred proteins/peptides, as a model to demonstrate our proposed ITC method in tracking the isolation and purification of two distinct target proteins, a major component and a minor component. Identities of fished out target proteins were confirmed by amino acid sequencing and inhibition assays. This method has the potential to make a significant advancement in the area of identifying orphan target proteins and inhibitor screening in drug discovery and characterization.

  6. Role of biomolecules on annulus fibrosus micromechanics: effect of enzymatic digestion on elastic and failure properties.

    Science.gov (United States)

    Isaacs, Jessica L; Vresilovic, Edward; Sarkar, Sumona; Marcolongo, Michele

    2014-12-01

    Uniaxial tension was applied to selectively digested single lamellar human cadaveric annulus fibrosus specimens to investigate the role of different biomolecules in annular biomechanics. Single layered and inter-lamellar annulus fibrosus samples were obtained from 10 isolated cadaveric lumbar intervertebral discs in one of four orientations: longitudinal, transverse, radial, and circumferential. Within each orientation the samples were subjected to a selective enzymatic digestion protocol with collagenase, elastase, chondroitinase ABC, or 1× Phosphate Buffered Saline. Uniaxial tensile tests were performed to failure at a strain rate of 0.005s(-1). Failure stress and strain, and elastic moduli were compared among the digested conditions. The collagenase- and elastase-treated groups had the most significant effect on the mechanical properties among the orientation groups, decreasing the failure stress for both interlaminar and intralaminar groups. Collagenase-treated groups showed an increase in the failure strain following enzymatic digestion for the intralaminar groups and one interlaminar testing direction (circumferential). The chondroitinase ABC-treated group only had a significant impact on the single layer orientations, decreasing the failure stress and strain (intralaminar group). The digested properties described provide insights into the laminar mechanical behavior and the role of the molecular components to the annular mechanical behavior. Understanding annular mechanics may prove insightful in diagnosis, prevention and repair of debilitating intervertebral disc disorders and manufacturing of tissue-engineered annulus. PMID:25212387

  7. Spatially controlled immobilisation of biomolecules: A complete approach in green chemistry

    Science.gov (United States)

    Grinenval, Eva; Nonglaton, Guillaume; Vinet, Françoise

    2014-01-01

    The development of 'green' sensors is a challenging task in the field of biomolecule sensing, for example in the detection of cardiac troponin-I (cTnI). In the present work a complete approach in green chemistry was developed to create chemically active patterns for the immobilisation of biological probes. This key technology is discussed on the basis of the twelve green chemistry principles, and is a combination of surface patterning by spotting and surface chemistries modified by molecular vapour deposition. The (1H,1H,2H,2H)-perfluorodecyltrichlorosilane (FDTS) was used as a novel anti-adsorption layer while the 3,4-epoxybutyltrimethoxysilane (EBTMOS) was used to immobilise probes. Oligonucleotides and the anti-cTnI antibody were studied. The spatially controlled immobilisation of probes was characterised by fluorescence. The demonstrated surface modification has broad applications in areas such as diagnostics and bio-chemical sensing. Moreover, the environmental impacts of surface patterning and surface chemistry were discussed from a 'greenness' point of view.

  8. Review: Bioanalytical applications of biomolecule-functionalized nanometer-sized doped silica particles

    International Nuclear Information System (INIS)

    Recent research has looked to develop innovative and powerful novel biofunctionalized nanometer-sized silica particles, controlling and tailoring their properties in a very predictable manner to meet the needs of specific applications. The silica shells of these particles facilitate a wide variety of surface reactions and allow conjugation with biomolecules like proteins and DNA. There exist a multitude of possible applications of fabricated nanoparticles in biotechnology and medicine. In particular, they have proved to be highly useful for biosensing, assay labelling, bioimaging, and in research on a variety of molecular tags in cellular and molecular biology. Techniques commonly rely on the use of silica-coated semiconductor quantum dots, organic dyes, magnetic particles, and Raman active particles. Inorganic-biological hybrid particles combine the properties of both materials, i.e., the spectroscopic characteristics of the entrapped nanocrystal, and the biomolecular function of the conjugated entity. Rather than being exhaustive, this review focuses on selected examples to illustrate novel concepts and promising applications. Approaches described include the encoding of silica nanoparticles with different groups, and conjugation with various biological entities. Further, promising applications in bioanalysis are considered and discussed.

  9. Extracting biomolecule collision cross sections from the high-resolution FT-ICR mass spectral linewidths.

    Science.gov (United States)

    Jiang, Ting; Chen, Yu; Mao, Lu; Marshall, Alan G; Xu, Wei

    2016-01-14

    It is known that the ion collision cross section (CCS) may be calculated from the linewidth of a Fourier transform ion cyclotron resonance (FT-ICR) mass spectral peak at elevated pressure (e.g., ∼10(-6) Torr). However, the high mass resolution of FT-ICR is sacrificed in those experiments due to high buffer gas pressure. In this study, we describe a linewidth correction method to eliminate the windowing-induced peak broadening effect. Together with the energetic ion-neutral collision model previously developed by our group, this method enables the extraction of CCSs of biomolecules from high-resolution FT-ICR mass spectral linewidths, obtained at a typical operating buffer gas pressure of modern FT-ICR instruments (∼10(-10) Torr). CCS values of peptides including MRFA, angiotensin I, and bradykinin measured by the proposed method agree well with ion mobility measurements, and the unfolding of protein ions (ubiquitin) at higher charge states is also observed. PMID:26314765

  10. EFFECT OF CARBOFURAN ON THE FORMATION OF SOME BIOMOLECULES IN BRINJAL (SOLANUM MELONGENA L. LEAF

    Directory of Open Access Journals (Sweden)

    MANZOOR A, ASHRAFI

    2014-09-01

    Full Text Available The present work was carried out with the objective to study the effect of carbofuran on the quantitative formation of carbohydrate, total free amino acids, protein, total phenol and total chlorophyll contents in brinjal leaf as recorded on 1, 7, 14, 21, 28 and 35 days after application (DAA. The carbohydrate content decreased to the extent of 3.36, 4.53 and 4.60% respectively against control (T1 : 0, recommended (T2 : 33.0 kg ha–1 and double of recommended (T3 : 66.0 kg ha–1 doses of carbofuran formulation on the 35th DAA in comparison with 1st DAA. The total free amino acid content decreased to 42.82, 45.84 and 49.89% respectively against the above doses. In case of protein content also an overall decrease of 45.28, 43.10 and 45.61% with regards to 1st DAA was observed. The total phenol content, on the contrary, recorded an increase of 18.85, 21.77 and 5.35% respectively in case of above three doses. The total chlorophyll content again exhibited a decrease of 20.99, 22.73 and 36.05% respectively. So the formation of all the biomolecules under study except phenol in brinjal leaf was found to decrease with passage of time as an effect of application of carbofuran.

  11. Study on the biodistribution of deuterated biomolecules in mice aiming at new Γ imaging agents

    International Nuclear Information System (INIS)

    Deuterated compounds (2H-compounds) labeled with 14C prepared from deuterated algae, Chlorella ellipsoidea, were examined for their time-coursed distribution in mice after intravenous administration. The 14C-2H-compounds were fractionated and isolated from algae grown in practically 100 mol% 2H2O in the presence of 14C-bicarbonate. The fractions obtained were the 'basic' and 'acid' fractions, composed mainly of amino acids and sugar phosphates, respectively, and glucose, galactose, and lipid fractions. All fractions were examined for their biodistribution in mice bearing Ehrlich solid tumor in comparison with the fractions isolated from ordinary Chlorella (1H-Chlorella). 2H-Compounds thus examined showed some behaviors different from 1H-compounds. The 2H-'basic' fraction distributed more slowly in heart, lung and liver than the 1H-fraction. The 2H-specific large distribution in tumor was also observed on this fraction. The 2H-dependent characteristics in the distribution of glucose and galactose differed. The 2H-glucose level was lower in blood and higher in brain, resulting in a brain/blood ratio approximately twice that of 1H-glucose, while 2H-galactose did not show such a characteristic. These findings may be useful for the application of 2H-biomolecules to functional radio-imaging agents for nuclear medicine. (author)

  12. Automated astatination of biomolecules - a stepping stone towards multicenter clinical trials

    Science.gov (United States)

    Aneheim, Emma; Albertsson, Per; Bäck, Tom; Jensen, Holger; Palm, Stig; Lindegren, Sture

    2015-07-01

    To facilitate multicentre clinical studies on targeted alpha therapy, it is necessary to develop an automated, on-site procedure for conjugating rare, short-lived, alpha-emitting radionuclides to biomolecules. Astatine-211 is one of the few alpha-emitting nuclides with appropriate chemical and physical properties for use in targeted therapies for cancer. Due to the very short range of the emitted α-particles, this therapy is particularly suited to treating occult, disseminated cancers. Astatine is not intrinsically tumour-specific; therefore, it requires an appropriate tumour-specific targeting vector, which can guide the radiation to the cancer cells. Consequently, an appropriate method is required for coupling the nuclide to the vector. To increase the availability of astatine-211 radiopharmaceuticals for targeted alpha therapy, their production should be automated. Here, we present a method that combines dry distillation of astatine-211 and a synthesis module for producing radiopharmaceuticals into a process platform. This platform will standardize production of astatinated radiopharmaceuticals, and hence, it will facilitate large clinical studies focused on this promising, but chemically challenging, alpha-emitting radionuclide. In this work, we describe the process platform, and we demonstrate the production of both astaine-211, for preclinical use, and astatine-211 labelled antibodies.

  13. AFNMR: automated fragmentation quantum mechanical calculation of NMR chemical shifts for biomolecules

    Energy Technology Data Exchange (ETDEWEB)

    Swails, Jason [Rutgers University, Department of Chemistry and Chemical Biology and BioMaPS Institute (United States); Zhu, Tong; He, Xiao, E-mail: xiaohe@phy.ecnu.edu.cn [East China Normal University, State Key Laboratory of Precision Spectroscopy, Institute of Theoretical and Computational Science (China); Case, David A., E-mail: case@biomaps.rutgers.edu [Rutgers University, Department of Chemistry and Chemical Biology and BioMaPS Institute (United States)

    2015-10-15

    We evaluate the performance of the automated fragmentation quantum mechanics/molecular mechanics approach (AF-QM/MM) on the calculation of protein and nucleic acid NMR chemical shifts. The AF-QM/MM approach models solvent effects implicitly through a set of surface charges computed using the Poisson–Boltzmann equation, and it can also be combined with an explicit solvent model through the placement of water molecules in the first solvation shell around the solute; the latter substantially improves the accuracy of chemical shift prediction of protons involved in hydrogen bonding with solvent. We also compare the performance of AF-QM/MM on proteins and nucleic acids with two leading empirical chemical shift prediction programs SHIFTS and SHIFTX2. Although the empirical programs outperform AF-QM/MM in predicting chemical shifts, the differences are in some cases small, and the latter can be applied to chemical shifts on biomolecules which are outside the training set employed by the empirical programs, such as structures containing ligands, metal centers, and non-standard residues. The AF-QM/MM described here is implemented in version 5 of the SHIFTS software, and is fully automated, so that only a structure in PDB format is required as input.

  14. Co-detection: ultra-reliable nanoparticle-based electrical detection of biomolecules in the presence of large background interference.

    Science.gov (United States)

    Liu, Yang; Gu, Ming; Alocilja, Evangelyn C; Chakrabartty, Shantanu

    2010-11-15

    An ultra-reliable technique for detecting trace quantities of biomolecules is reported. The technique called "co-detection" exploits the non-linear redundancy amongst synthetically patterned biomolecular logic circuits for deciphering the presence or absence of target biomolecules in a sample. In this paper, we verify the "co-detection" principle on gold-nanoparticle-based conductimetric soft-logic circuits which use a silver-enhancement technique for signal amplification. Using co-detection, we have been able to demonstrate a great improvement in the reliability of detecting mouse IgG at concentration levels that are 10(5) lower than the concentration of rabbit IgG which serves as background interference. PMID:20864327

  15. Development of a combined surface plasmon resonance/surface acoustic wave device for the characterization of biomolecules

    International Nuclear Information System (INIS)

    It is known that acoustic sensor devices, if operated in liquid phase, are sensitive not just to the mass of the analyte but also to various other parameters, such as size, shape, charge and elastic constants of the analyte as well as bound and viscously entrained water. This can be used to extract valuable information about a biomolecule, particularly if the acoustic device is combined with another sensor element which is sensitive to the mass or amount of analyte only. The latter is true in good approximation for various optical sensor techniques. This work reports on the development of a combined surface plasmon resonance/surface acoustic wave sensor system which is designed for the investigation of biomolecules such as proteins or DNA. Results for the deposition of neutravidin and DNA are reported

  16. Aequorin as a bioluminescent indicator for use in the determination of biomolecules in single cells. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Sylvia Daunert

    2000-02-17

    During this funding period, the laboratories of Drs. Anderson and Daunert have performed a considerable amount of work toward addressing the issues associated with small volume analysis necessary for single cell studies. In that respect, their research has been focused on (1) developing new assays that can be miniaturized and are suitable for small volume and single cell analysis; (2) fabricating pL-vials that simulate the volume of single cells and setting up instrumentation capable of low-volume detection; (3) developing reproducible and reliable microinjection techniques; (4) developing methods of analysis for biomolecules in the pL-vials and employing these assays in the detection of biomolecules in single cells. The accomplishments attained in all these areas are described below. A total of 24 publications and 35 presentations have resulted from this work.

  17. DNA-based Nanoconstructs for the Detection of Ions and Biomolecules with Related Raman/SERS Signature Studies

    Science.gov (United States)

    Brenneman, Kimber L.

    The utilization of DNA aptamers and semiconductor quantum dots (QDs) for the detection of ions and biomolecules was investigated. In recent years, there have been many studies based on the use of DNA and RNA aptamers, which are single stranded oligonucleotides capable of binding to biomolecules, other molecules, and ions. In many of these cases, the conformational changes of these DNA and RNA aptamers are suitable to use fluorescence resonant energy transfer (FRET) or nanometal surface energy transfer (NSET) techniques to detect such analytes. Coupled with this growth in such uses of aptamers, there has been an expanded use of semiconductor quantum dots as brighter, longer-lasting alternatives to fluorescent dyes in labeling and detection techniques of interest in biomedicine and environmental monitoring. Thrombin binding aptamer (TBA) and a zinc aptamer were used to detect mercury, lead, zinc, and cadmium. These probes were tested in a liquid assay as well as on a filter paper coupon. Biomolecules were also studied and detected using surface-enhanced Raman spectroscopy (SERS), including DNA aptamers and C-reactive protein (CRP). Raman spectroscopy is a useful tool for sensor development, label-free detection, and has the potential for remote sensing. Raman spectra provide information on the vibrational modes or phonons, between and within molecules. Therefore, unique spectral fingerprints for single molecules can be obtained. SERS is accomplished through the use of substrates with nanometer scale geometries made of metals with many free electrons, such as silver, gold, or copper. In this research silver SERS substrates were used to study the SERS signature of biomolecules that typically produce very weak Raman signals.

  18. Fragmentation study of isolated and nanosolvated biomolecules induced by collision with multiply charged ions and neutral particles

    OpenAIRE

    Bernigaud, Virgile

    2009-01-01

    This thesis concerns a gas phase study of the fragmentation of biomolecular systems induced by slow collisions with multiply charged ions (in the keV-region), alkali atoms and rare gases. The main objective was to study the physical processes involved in the dissociation of highly electronically excited systems. In order to elucidate the intrinsic properties of certain biomolecules (porphyrins and amino acids) we have performed experiments in the gas phase with isolated systems. The obtained ...

  19. Redox Reactivity of Cerium Oxide Nanoparticles Induces the Formation of Disulfide Bridges in Thiol-Containing Biomolecules.

    Science.gov (United States)

    Rollin-Genetet, Françoise; Seidel, Caroline; Artells, Ester; Auffan, Mélanie; Thiéry, Alain; Vidaud, Claude

    2015-12-21

    The redox state of disulfide bonds is implicated in many redox control systems, such as the cysteine-cystine couple. Among proteins, ubiquitous cysteine-rich metallothioneins possess thiolate metal binding groups susceptible to metal exchange in detoxification processes. CeO2 NPs are commonly used in various industrial applications due to their redox properties. These redox properties that enable dual oxidation states (Ce(IV)/Ce(III)) to exist at their surface may act as oxidants for biomolecules. The interaction among metallothioneins, cysteine, and CeO2 NPs was investigated through various biophysical approaches to shed light on the potential effects of the Ce(4+)/Ce(3+) redox system on the thiol groups of these biomolecules. The possible reaction mechanisms include the formation of a disulfide bridge/Ce(III) complex resulting from the interaction between Ce(IV) and the thiol groups, leading to metal unloading from the MTs, depending on their metal content and cluster type. The formation of stable Ce(3+) disulfide complexes has been demonstrated via their fluorescence properties. This work provides the first evidence of thiol concentration-dependent catalytic oxidation mechanisms between pristine CeO2 NPs and thiol-containing biomolecules. PMID:26566067

  20. Detection of prostate-specific antigen with biomolecule-gated AlGaN/GaN high electron mobility transistors

    International Nuclear Information System (INIS)

    In order to improve the sensitivity of AlGaN/GaN high electron mobility transistor (HEMT) biosensors, a simple biomolecule-gated AlGaN/GaN HEMT structure was designed and successfully fabricated for prostate specific antigen (PSA) detection. UV/ozone was used to oxidize the GaN surface and then a 3-aminopropyl trimethoxysilane (APTES) self-assembled monolayer was bound to the sensing region. This monolayer serves as a binding layer for attachment of the prostate specific antibody (anti-PSA). The biomolecule-gated AlGaN/GaN HEMT sensor shows a rapid and sensitive response when the target prostate-specific antigen in buffer solution was added to the antibody-immobilized sensing area. The current change showed a logarithm relationship against the PSA concentration from 0.1 pg/ml to 0.993 ng/ml. The sensitivity of 0.215% is determined for 0.1 pg/ml PSA solution. The above experimental result of the biomolecule-gated AlGaN/GaN HEMT biosensor suggested that this biosensor might be a useful tool for prostate cancer screening. (paper)

  1. Nanorods of a new metal-biomolecule coordination polymer showing novel bidirectional electrocatalytic activity and excellent performance in electrochemical sensing.

    Science.gov (United States)

    Yang, Jiao; Zhou, Bo; Yao, Jie; Jiang, Xiao-Qing

    2015-05-15

    Metal organic coordination polymers (CPs), as most attractive multifunctional materials, have been studied extensively in many fields. However, metal-biomolecule CPs and CPs' electrochemical properties and applications were studied much less. We focus on this topic aiming at electrochemical biosensors with excellent performance and high biocompatibility. A new nanoscaled metal-biomolecule CP, Mn-tyr, containing manganese and tyrosine, was synthesized hydrothermally and characterized by various techniques, including XRD, TEM, EDS, EDX mapping, elemental analysis, XPS, and IR. Electrode modified with Mn-tyr showed novel bidirectional electrocatalytic ability toward both reduction and oxidation of H2O2, which might be due to Mn. With the assistance of CNTs, the sensing performance of Mn-tyr/CNTs/GCE was improved to a much higher level, with high sensitivity of 543 mA mol(-1) L cm(-2) in linear range of 1.00×10(-6)-1.02×10(-4) mol L(-1), and detection limit of 3.8×10(-7) mol L(-1). Mn-tyr/CNTs/GCE also showed fast response, high selectivity, high steadiness and reproducibility. The excellent performance implies that the metal-biomolecule CPs are promising candidates for using in enzyme-free electrochemical biosensing. PMID:25037318

  2. Sensitivity improvement of an electrical sensor achieved by control of biomolecules based on the negative dielectrophoretic force.

    Science.gov (United States)

    Kim, Hye Jin; Kim, Jinsik; Yoo, Yong Kyoung; Lee, Jeong Hoon; Park, Jung Ho; Hwang, Kyo Seon

    2016-11-15

    Effective control of nano-scale biomolecules can enhance the sensitivity and limit of detection of an interdigitated microelectrode (IME) sensor. Manipulation of the biomolecules by dielectrophoresis (DEP), especially the negative DEP (nDEP) force, so that they are trapped between electrodes (sensing regions) was predicted to increase the binding efficiency of the antibody and target molecules, leading to a more effective reaction. To prove this concept, amyloid beta 42 (Aβ42) and prostate specific antigen (PSA) protein were respectively trapped between the sensing region owing to the nDEP force under 5V and 0.05V, which was verified with COMSOL simulation. Using the simulation value, the resistance change (ΔR/Rb) of the IME sensor from the specific antibody-antigen reaction of the two biomolecules and the change in fluorescence intensity were compared in the reference (pDEP) and nDEP conditions. The ΔR/Rb value improved by about 2-fold and 1.66-fold with nDEP compared to the reference condition with various protein concentrations, and these increases were confirmed with fluorescence imaging. Overall, nDEP enhanced the detection sensitivity for Aβ42 and PSA by 128% and 258%, respectively, and the limit of detection improved by up to 2-orders of magnitude. These results prove that DEP can improve the biosensor's performance. PMID:27449966

  3. A Ruthenium(II) Complex Supported by Trithiacyclononane and Aromatic Diimine Ligand as Luminescent Switch-On Probe for Biomolecule Detection and Protein Staining

    Science.gov (United States)

    Wong, Chun-Yuen; Chung, Lai-Hon; Lin, Sheng; Chan, Daniel Shiu-Hin; Ma, Dik-Lung

    2014-01-01

    A new ruthenium(II) complex has been developed for detection of biomolecules. This complex is highly selective for histidine over other amino acids and has been applied to protein staining in an SDS-PAGE gel. PMID:25409703

  4. Theoretical foundation and experimental proof of the accumulating transfer of tritium from water into DNA and other biomolecules in vitro and in vivo

    International Nuclear Information System (INIS)

    Theoretical foundation and experimental proof of the accumulating transfer of tritium from water into DNA and other biomolecules were presented using the data of experiments on fish sperm DNA and piglet's liver (in vitro tests) and maize and barley (in vivo tests). Heisenberg's uncertainty principle, which describes a fundamental property of matter, predicts the light hydrogen isotope to prefer strong hydrogen bridge positions (with large local uncertainty). In contrast, the heavy hydrogen isotope tritium originally localized in water, should finally be found in the exchangeable hydrogen bridge positions of proteins, carbohydrates and nucleotides which are definitely less strong than those of water. Fractionation factor of tritium and protonium measured between water and DNA as well as the mixture of biomolecules of liver confirm this conclusion and show tritium accumulation biomolecules. Furthermore, the elevated rate of natural increase in tritium concentration in tissue solids of growing maize and barley confirm the accumulating tritium transfer from water to biomolecules taking place in vivo

  5. A Ruthenium(II) Complex Supported by Trithiacyclononane and Aromatic Diimine Ligand as Luminescent Switch-On Probe for Biomolecule Detection and Protein Staining

    Science.gov (United States)

    Wong, Chun-Yuen; Chung, Lai-Hon; Lin, Sheng; Chan, Daniel Shiu-Hin; Leung, Chung-Hang; Ma, Dik-Lung

    2014-11-01

    A new ruthenium(II) complex has been developed for detection of biomolecules. This complex is highly selective for histidine over other amino acids and has been applied to protein staining in an SDS-PAGE gel.

  6. Hitos de la perspectiva molar del condicionamiento clásico

    Directory of Open Access Journals (Sweden)

    Andrés M. Pérez Acosta

    2003-01-01

    Full Text Available En este artículo se revisan los acontecimientos históricos fundamentales en la teoría del condicionamiento clásico como fenómeno psicológico –comportamental o cognoscitivo–, es decir, desde una perspectiva molar, en oposición a una perspectiva molecular, que es propia de las neurociencias. Se analizan los siguientes acontecimientos o hitos: la teoría reflexológica de Vladimir Bechterev, la perspectiva conductista radical de B. F. Skinner, el modelo de Rescorla y Wagner (1972, los modelos atencionales de Mackintosh (1975 y de Pearce y Hall (1980, las teorías que se basan en los procesos oponentes, de Allan Wagner (1981; Wagner & Brandon, 1989, y las teorías que se basan en el control temporal del comportamiento (Gallistel & Gibbon, 2002.

  7. Historiografía comparada: problemas y perspectivas

    Directory of Open Access Journals (Sweden)

    Chris Lorenz

    2005-12-01

    Full Text Available In this text contributions related are abridged - direct or indirectly - with the historiography of world war two. The comparative historiography is placed as a gender related to a typology that classified historiography theories over an extended sequence from the general and philosophical to the particular and empirical. Resides, it also places the recent debates on the “fragmentation " of the historiography in a comparative perspective. Due that historiography is the history of the written history -and therefore a reconstruction of reconstructions- we find the problem of comparison in historiography twice. The historiographer is not alone confronting with relative comparative judgments of the historic reconstructions themselves but also related to the historiography reconstructions of those historic reconstructions.//En este texto se compendian contribuciones relacionadas - directa o indirectamente - con la historiografía de la segunda guerra mundial. Se ubica a la historiografía comparada como un género en relación a una tipología que clasifica teorías de historiografía sobre una secuencia extendida de lo general y filosófico a lo particular y empírico. Además, coloca los recientes debates sobre la "fragmentación" de la historiografía en una perspectiva comparada. Debido a que la historiografía es la historia de la historia escrita - y por lo tanto una reconstrucción de reconstrucciones - encontramos el problema de la comparación en historiografía dos veces. El historiógrafo no sólo está confrontado con los juicios comparados relativos a las reconstrucciones históricas mismas, sino también relativas a las reconstrucciones historiográficas de aquellas reconstrucciones históricas.

  8. en la perspectiva de la Ingeniería Concurrente

    Directory of Open Access Journals (Sweden)

    Carmenza Luna Amaya

    2007-01-01

    Full Text Available Este artículo se preparó con el fin de exponer las generalidades de los resultados parciales de la investigación titulada “Diseño del Modelo del Proceso de Desarrollo de Producto (PDP del Sector Metalmecánico de Barranquilla en la Perspectiva de la Ingeniería Concurrente”. Se presenta una breve descripción de las herramientas utilizadas para modelar el PDP gráfica y conceptualmente, de modo que logre obtenerse una caracterización cercana a las condiciones generales actuales del proceso, según los puntos de interés de la Ingeniería Concurrente (IC, agrupados éstos en cinco dimensiones: Organización, Recursos Humanos, Información, Tecnología y Mercado. De igual forma, se orientan al apoyo de la dirección, a la conformación de equipos multidisciplinarios y al uso de recursos tecnológicos. Estas generalidades son resultado del estudio de dichas condiciones actuales del PDP en cinco (5 empresas del Sector Metalmecánico de la ciudad, revisando en cada una de ellas igual listado de criterios para luego hacer el correspondiente análisis. Este trabajo forma parte de los proyectos que desarrolla el Grupo de Investigación en Productividad y Competitividad, en su línea de estudio en Ingeniería Concurrente con el objetivo de estudiar, conocer y difundir la IC como filosofía a nivel empresarial

  9. Las acciones punitivas físicas: una perspectiva intercultural

    Directory of Open Access Journals (Sweden)

    María del Mar BADIA MARTÍN

    2009-11-01

    Full Text Available RESUMEN: En este artículo se enmarca el término de castigo corporal diferenciándolo del de abuso físico, a la vez que se realiza un análisis sobre la perspectiva de diferentes países con relación a la aplicación de dicha forma de castigo. La investigación y la teoría analizada, muestran cómo ciertas sociedades todavía reclaman el uso del castigo corporal como una forma más para frenar los comportamientos molestos. Esto nos puede llevar a pensar que no se debe abandonar la tesis sobre el hecho de que esta estrategia es rechazada en la actualidad por todos los sectores de la sociedad, sino que debemos ser sensibles a la idea de que ciertos profesionales y familias lo consideran un instrumento más para la corrección de conductas consideradas como no correctas.ABSTRACT: In this article the term corporal punishment is differentiated from that of physical abuse, and at the same time an analysis is made of the perspective of different countries in relation to the application of this type of punishment. The research and theory analysed show how certain societies still call for the use of corporal punishment as one more way to stop troublesome behaviour. This can lead us to think that the thesis that this strategy is currently rejected by all sectors of society should not be abandoned, but we should be aware that certain professionals and families still consider it one more instrument for correcting behaviour considered as incorrect.

  10. Burnout en profesores: Una perspectiva social del intercambio

    Directory of Open Access Journals (Sweden)

    WILMAR B. SCHAUFELI

    2005-01-01

    Full Text Available Se propone una perspectiva teórica sobre burnout en profesores, basada en principios de intercambio social. Se argumenta que el burnout se produce por una falta de reciprocidad; por un desajuste entre inversiones y resultados. Los profesores quemados se caracterizan por haber dado demasiado durante demasiado tiempo y por recibir demasiado poco a cambio. Según la teoría del intercambio social, la falta de reciprocidad podría desarrollarse a tres niveles: interpersonal (relación con estudiantes, a nivel de equipo (relaciones con compañeros, y a nivel organizacional (relación con la escuela. Estudios empíricos en profesores mostraron que el ajuste entre 'dar y recibir' se rompe, sobretodo en los niveles interpersonal y organizacional. Además, la falta de reciprocidad se asocia con distrés y conductas de abandono. Se observa un efecto genérico: cuando el equilibrio 'dar y recibir' se rompe se produce agotamiento emocional (síntoma corazón del burnout. Además, se observan efectos de las conductas de abandono específico para cada nivel de intercambio social: la falta de reciprocidad con los estudiantes provoca despersonalización (segunda dimensión del burnout; la falta de reciprocidad con los colegas acaba en conductas de abandono de los colegas; y la falta de reciprocidad con la escuela en abandono psicológico (reducido compromiso organizacional y conductual (absentismo por enfermedad de la escuela.

  11. Submicron-resolution photoacoustic microscopy of endogenous light-absorbing biomolecules

    Science.gov (United States)

    Zhang, Chi

    Photoacoustic imaging in biomedicine has the unique advantage of probing endogenous light absorbers at various length scales with a 100% relative sensitivity. Among the several modalities of photoacoustic imaging, optical-resolution photoacoustic microscopy (OR-PAM) can achieve high spatial resolution, on the order of optical wavelength, at high spatial resolution in 3D. The lateral resolution was improved by using optical objectives with high numerical apertures for optical focusing. The axial resolution was improved by using broadband ultrasonic transducers for ultrasound detection. We achieved 220 nm lateral resolution in transmission mode, 0.43 microm lateral resolution in reflection mode, 7.6 microm axial resolution in normal tissue, and 5.8 microm axial resolution with silicone oil immersion/injection. The achieved lateral resolution and axial resolution were the finest reported at the time. With high-resolution in 3D, PAM was demonstrated to resolve cellular and subcellular structures in vivo, such as red blood cells and melanosomes in melanoma cells. Compared with previous PAM systems, our high-resolution PAM could resolve capillaries in mouse ears more clearly. As an example application, we demonstrated intracellular temperature imaging, assisted by fluorescence signal detection, with sub-degree temperature resolution and sub-micron lateral resolution. The second part of this dissertation describes the exploration of endogenous light-absorbing biomolecules for PAM. We demonstrated cytochromes and myoglobin as new absorption contrasts for PAM and identified the corresponding optimal wavelengths for imaging. Fixed fibroblasts on slides and mouse ear sections were imaged by PAM at 422 nm and 250 nm wavelengths to reveal cytoplasms and nuclei, respectively, as confirmed by standard hematoxylin and eosin (H&E) histology. By imaging a blood-perfused mouse heart at 532 nm down to 150 microm in depth, we derived the myocardial sheet thickness and the cleavage

  12. Development of methods for the purification of 67Ga and 68Ga for biomolecules labeling

    International Nuclear Information System (INIS)

    For more than fifty years, the long-lived 68Ge/68Ga generators have been in development, obtaining 68Ga without the need of having in house cyclotron, which is a considerable convenience for PET centers that have no nearby cyclotrons. 68Ga decays 89% by positron emission and low photon emission (1077 keV) and the physical half life of 67.7 minutes is compatible with the pharmacokinetics of low biomolecular weight substances like peptides and antibody fragments. Moreover, its established metallic chemistry allows it to be stably bound to the carrier peptide sequence via a suitable bifunctional chelator, such as DOTA. All these reasons together with the technology of PET/CT allowed advances in molecular imaging, in particular in the diagnosis of neuroendocrine diseases. However, the eluate from the commercial 68Ge/68Ga generators still contains high levels of long lived 68Ge, besides other metallic impurities, which competes with 68Ga with a consequent reduction of the labeling yield of biomolecules, such as Fe3+ and Zn2+. Thus, the lower the amount of impurities in the eluate, the competition between the radiolabeled and unlabeled peptide by the receptor will be smaller and the quality of imaging will be better, a subsequent purification step is needed after the generator elution. The aim of this work is to evaluate different purifications methods of 68Ga to label biomolecules, with emphasis on the study of the chemical impurities contained in the eluate and to develop a new purification method. Several purification methods were studied. Many cationic resin were tested simulating the commercial process. 68Ga is adsorbed in cationic resin, which is not commercial available and eluted in acid/acetone solution. The use of minor particles of cationic resin AG50W-X4 (200-400 mesh) showed the best results. An innovate method was the extraction chromatography, which is based on the absorption of diisopropyl ether in XAD 16 and 68Ga recovery in deionized water. Although the

  13. High-Precision Dispensing of Nanoliter Biofluids on Glass Pedestal Arrays for Ultrasensitive Biomolecule Detection.

    Science.gov (United States)

    Chen, Xiaoxiao; Liu, Yang; Xu, QianFeng; Zhu, Jing; Poget, Sébastien F; Lyons, Alan M

    2016-05-01

    Precise dispensing of nanoliter droplets is necessary for the development of sensitive and accurate assays, especially when the availability of the source solution is limited. Conventional approaches are limited by imprecise positioning, large shear forces, surface tension effects, and high costs. To address the need for precise and economical dispensing of nanoliter volumes, we developed a new approach where the dispensed volume is dependent on the size and shape of defined surface features, thus freeing the dispensing process from pumps and fine-gauge needles requiring accurate positioning. The surface we fabricated, called a nanoliter droplet virtual well microplate (nVWP), achieves high-precision dispensing (better than ±0.5 nL or ±1.6% at 32 nL) of 20-40 nL droplets using a small source drop (3-10 μL) on isolated hydrophilic glass pedestals (500 μm on a side) bonded to arrays of polydimethylsiloxane conical posts. The sharp 90° edge of the glass pedestal pins the solid-liquid-vapor triple contact line (TCL), averting the wetting of the glass sidewalls while the fluid is prevented from receding from the edge. This edge creates a sufficiently large energy barrier such that microliter water droplets can be poised on the glass pedestals, exhibiting contact angles greater >150°. This approach relieves the stringent mechanical alignment tolerances required for conventional dispensing techniques, shifting the control of dispensed volume to the area circumscribed by the glass edge. The effects of glass surface chemistry and dispense velocity on droplet volume were studied using optical microscopy and high-speed video. Functionalization of the glass pedestal surface enabled the selective adsorption of specific peptides and proteins from synthetic and natural biomolecule mixtures, such as venom. We further demonstrate how the nVWP dispensing platform can be used for a variety of assays, including sensitive detection of proteins and peptides by fluorescence

  14. Heavy metal induced biomolecule and genotoxic changes in earthworm Eisenia fetida

    Directory of Open Access Journals (Sweden)

    G. Muthukaruppan

    2015-09-01

    Full Text Available A vibrational [Fourier transform infrared (FTIR] spectroscopic method was used for the structural and compositional analysis of earthworm Eisenia fetida by monitoring of metal binding and further transformations in live cells. The FTIR analyses for metals taken up by the E. fetida will be useful for analyzing the impact of the heavy metal stress on the worm metabolism. The epigeic earthworm E. fetida were exposed to 100 %, 75 %, 50 %, 30 %, 25 %, 15 % and 5 % of dried automobile service station waste mud. All the earthworms exposed in the 100 %, 75 % and 50 % concentrations didn’t survived within 10days. Further experiments were conducted with 25 %, 15 % and 5 % concentration of wastes. Each concentration level was tested with three replicates using 10 animals and the metabolic response after exposure to the heavy metal containing service station waste mud was assessed by FTIR. Furthermore we also emphasized that DNA damage was confirmed with the use of other biomarker like comet assay. The peaks at 1045, 1080, 1236 cm−1 and 1650 cm−1 represented the overall susceptibility of nucleotides, phospholipids, DNA and RNA. Nucleic acids and proteins were modified due to heavy metal accumulation. In flow-through, single cell gel electrophoresis revealed the degradation nuclear DNA. Heavy metals accumulation in the worms was measured and it was found that lead, zinc and copper accumulation increased in the treatment group. Without the use of biomarkers for identifying ecological risks of land contamination, traditional assessment would be difficult to interpret. This new FTIR based biomolecules study revealed a clear molecule shift in the exposed worms, due to heavy metal accumulation.

  15. Cytoplasmic electric fields and electroosmosis: possible solution for the paradoxes of the intracellular transport of biomolecules.

    Directory of Open Access Journals (Sweden)

    Victor P Andreev

    Full Text Available The objective of the paper is to show that electroosmotic flow might play an important role in the intracellular transport of biomolecules. The paper presents two mathematical models describing the role of electroosmosis in the transport of the negatively charged messenger proteins to the negatively charged nucleus and in the recovery of the fluorescence after photobleaching. The parameters of the models were derived from the extensive review of the literature data. Computer simulations were performed within the COMSOL 4.2a software environment. The first model demonstrated that the presence of electroosmosis might intensify the flux of messenger proteins to the nucleus and allow the efficient transport of the negatively charged phosphorylated messenger proteins against the electrostatic repulsion of the negatively charged nucleus. The second model revealed that the presence of the electroosmotic flow made the time of fluorescence recovery dependent on the position of the bleaching spot relative to cellular membrane. The magnitude of the electroosmotic flow effect was shown to be quite substantial, i.e. increasing the flux of the messengers onto the nucleus up to 4-fold relative to pure diffusion and resulting in the up to 3-fold change in the values of fluorescence recovery time, and therefore the apparent diffusion coefficient determined from the fluorescence recovery after photobleaching experiments. Based on the results of the modeling and on the universal nature of the electroosmotic flow, the potential wider implications of electroosmotic flow in the intracellular and extracellular biological processes are discussed. Both models are available for download at ModelDB.

  16. Wavelength Selection For Laser Raman Spectroscopy of Putative Martian Habitats and Biomolecules

    Science.gov (United States)

    Wynn-Williams, D. D.; Newton, E. M. G.; Edwards, H. G. M.

    Pigments are key potential biomarkers for any former life on Mars because of the selective pressure of solar radiation on any biological system that could have evolved at its surface. We have found that the near -Infrared laser Raman spectrometer available to use was eminently suitable for diagnostic analysis of pigments because of their minimal autofluorescence at its 1064 nm excitation wav elength. However, we have now evaluated a diverse range of excitation wavelengths to confirm this choice, to ensure that we have the best technique to seek for pigments and their derivatives from any former surface life on Mars. The Raman is weak relative to fluorescence, which results in elevated baseline and concurrent swamping of Raman bands. We confirm the molecular information available from near-IR FT Raman spectra for two highly pigmented UV-tolerant epilithic Antarctic lichens (Acarospora chlorop hana and Caloplaca saxicola) from Victoria Land, a whole endolithic microbial community and endolithic cyanobacterium Chroococcidiopsis from within translucent sandstone of the Trans -Antarctic Mountains, and the free- living cyanobacterium Nostoc commune from Alexander Island, Antarctic Peninsula region. We also show that much of the information we require on biomolecules is not evident from lasers of shorter wavelengths. A miniature 1064 nm Raman spectrometer with an In-Ga-As detector sensitive to IR is being developed by Montana State University (now existing as a prototype) as the prime instrument for a proposed UK-led Mars rover mission (Vanguard). Preliminary spectra from this system confirm the suitability of the near-IR laser.

  17. Modelling of diffraction grating based optical filters for fluorescence detection of biomolecules.

    Science.gov (United States)

    Kovačič, M; Krč, J; Lipovšek, B; Topič, M

    2014-07-01

    The detection of biomolecules based on fluorescence measurements is a powerful diagnostic tool for the acquisition of genetic, proteomic and cellular information. One key performance limiting factor remains the integrated optical filter, which is designed to reject strong excitation light while transmitting weak emission (fluorescent) light to the photodetector. Conventional filters have several disadvantages. For instance absorbing filters, like those made from amorphous silicon carbide, exhibit low rejection ratios, especially in the case of small Stokes' shift fluorophores (e.g. green fluorescent protein GFP with λ exc = 480 nm and λ em = 510 nm), whereas interference filters comprising many layers require complex fabrication. This paper describes an alternative solution based on dielectric diffraction gratings. These filters are not only highly efficient but require a smaller number of manufacturing steps. Using FEM-based optical modelling as a design optimization tool, three filtering concepts are explored: (i) a diffraction grating fabricated on the surface of an absorbing filter, (ii) a diffraction grating embedded in a host material with a low refractive index, and (iii) a combination of an embedded grating and an absorbing filter. Both concepts involving an embedded grating show high rejection ratios (over 100,000) for the case of GFP, but also high sensitivity to manufacturing errors and variations in the incident angle of the excitation light. Despite this, simulations show that a 60 times improvement in the rejection ratio relative to a conventional flat absorbing filter can be obtained using an optimized embedded diffraction grating fabricated on top of an absorbing filter. PMID:25071964

  18. La perspectiva genealógica nietzscheana y la escritura de la historia

    OpenAIRE

    Moro Abadía, Oscar

    2002-01-01

    El presente articulo propone una definición de la perspectiva genealógica de F. Nietzsche (1844-1900) a través de la interpretación que de ella realizara Michel Foucault (1926-1984). Dicha perspectiva, convertida en una crítica de los valores, se constituye como instrumento del análisis histórico a través de tres de las líneas fundamentales que la definen: la critica del fundamento metafisico de la historia, la crítica del origen como lugar de la esencia y la pregunta por el valor d...

  19. Perspectivas educativas contemporáneas en América Latina

    OpenAIRE

    Valdez Hernández, Ena Luz

    2010-01-01

    En esta tesis doctoral se plantean perspectivas en la educación contemporánea de América Latina. El propósito de esta tesis es proporcionar alternativas en los procesos de formación para el desarrollo personal y la identidad sociocultural de los latinoamericanos. Tiene como objetivo general: Conocer los parámetros de nuestra educación latinoamericana y cuales son las perspectivas planteadas en el ámbito educativo para las próximas décadas del siglo XXI. En el primer capítulo, se plantea...

  20. Un modelo de referencia para definir la perspectiva organizacional de modelos de workflows

    OpenAIRE

    Stroppi, Luis Jesús Ramón; Villarreal, Pablo David

    2009-01-01

    El soporte que las herramientas de modelado y sistemas de gestión de workflows brindan a la perspectiva organizacional es limitado. Esto se debe a la falta de herramientas que permitan entender los requerimientos de distribución de trabajo definidos en un modelo de workflow. Este trabajo presenta un modelo de referencia que da soporte a la definición de la perspectiva organizacional de los modelos de workflows. El modelo provee un conjunto de atributos de actividad que permiten identificar lo...

  1. Perspectiva del (desempleo en Sonora, 2000-2015

    Directory of Open Access Journals (Sweden)

    Ernesto Peralta

    2004-01-01

    Full Text Available El objetivo de este artículo es pronosticar el número de personas que ofrecerán sus servicios frente al de los que podrían tener un empleo permanente1 en el estado mexicano de Sonora entre los años 2000 y 2015, contrastando el escenario de continuar las tendencias históricas del empleo con el de una propuesta de mayor crecimiento y reestructuración productiva que priorice actividades que exigen mano de obra en abundancia. Generar empleo formal o permanente implica esfuerzos de investigación e instrumentación en áreas como las de tecnología, educación, capacitación o financiamiento a la inversión, entre otras, lo cual requiere del análisis de especialistas. El objetivo aquí planteado es más modesto, pero dimensionar el número de los que ofrecerán sus servicios de trabajo contra la perspectiva de creación de empleos permanentes implica un reto a la economía sonorense, pues las personas que buscarán trabajo en el horizonte referido ya existen. La hipótesis que aquí se plantea es: si no se promueve el empleo permanente más allá de lo que la extensión de la tendencia histórica conlleva entre los años 2000 y 2015, la generación de este tipo de empleo se rezagará considerablemente respecto a la población que buscará ocuparse, ampliando el desempleo abierto y disfrazado.2 Este artículo tiene cuatro secciones. En la primera se presenta el rezago del empleo permanente respecto a la fuerza de trabajo; en la segunda se describe el marco teórico y el respectivo modelo de referencia; en la tercera, el método de trabajo y sus resultados, incluyendo las actividades propuestas para aumentar el empleo y las tasas de inversión para acelerar el crecimiento económico y la creación de empleos formales; la cuarta contiene conclusiones y recomendaciones. Se presenta un anexo estadístico con proyecciones demográficas y de fuerza de trabajo, así como la matriz de insumo-producto de Sonora.

  2. O Linux e a perspectiva da dádiva

    Directory of Open Access Journals (Sweden)

    Renata Apgaua

    2004-06-01

    Full Text Available O objetivo deste trabalho é analisar o surgimento e consolidação do sistema operacional Linux em um contexto marcado pela hegemonia de sistemas operacionais comerciais, sendo o Windows/Microsoft o exemplo paradigmático. O idealizador do Linux optou por abrir o seu código-fonte e oferecê-lo, gratuitamente, na Internet. Desde então, pessoas de diversas partes do mundo têm participado do seu desenvolvimento. Busca-se, assim, através deste estudo, analisar as características desse espaço de sociabilidade, onde as trocas apontam para outra lógica que não a do mercado. A proposta de compreender os laços sociais no universo Linux, a partir da perspectiva da dádiva, acaba remetendo a outra discussão, que também merecerá atenção nesse estudo, qual seja: a atualidade da dádiva. Releituras de Mauss, feitas por Godbout e Caillé, indicam que a dádiva, em seu "sistema de transformações", encontra-se presente nas sociedades contemporâneas, mas não apenas nos interstícios sociais, conforme afirmava o próprio Mauss.This work's goal is to analyze the appearance and consolidation of the Linux operational system in a context marked by the hegemony of commercial operational systems, taking the Windows/Microsoft as the paradigmatic example. The creator of Linux chose to make it open-source and offer it free of charge, in the Internet. Since then, people from the various parts of the world have participated in its development. This study, therefore, seeks to analyse the features of this space of sociability, where the exchange points to another logic different of that one adopted by the market. The proposal of comprehending the social ties of the Linux universe through the perspective of gift ends up sending us into another discussion, which will also deserve attention in this study, that would be: the recentness of gift. Re-interpretations of Mauss, made by Godbout and Caillé, indicate that gif, in its "changing system", is present in

  3. Terapia celular em doenças pulmonares: existem perspectivas?

    Directory of Open Access Journals (Sweden)

    João T. Ribeiro-Paes

    2009-05-01

    Full Text Available A terapia celular poderia ser conceituada de forma ampla e genérica como o emprego de células para tratamento de doenças. Apesar de um número não tão expressivo de relatos tendo o pulmão como objeto de estudo na terapia celular em pacientes humanos, há dados consistentes da literatura, tanto em humanos, quanto em modelos animais,que evidenciam a migração de células-tronco da medula óssea para o pulmão,em diferentes situações experimentais. Esses resultados forneceram o embasamento experimental para o emprego de células-tronco na regeneração do tecido pulmonar em modelos animais. Em nosso laboratório, vários projetos de pesquisa têm sido conduzidos com a finalidade de avaliar a resposta pulmonar (morfológica e funcional ao tratamento com células-tronco adultas em camundongos com doença pulmonar obstrutiva crônica (DPOC induzida experimentalmente. Os resultados obtidos, aliados àqueles de outros grupos de pesquisa, permitem aventar a possibilidade de aplicação, a curto prazo, da terapia celular em pacientes com DPOC. Em outra patologia pulmonar, fibrose cística (FC, cuja abordagem terapêutica com células-tronco apresenta aspectos particulares em relação às patologias pulmonares crônico-degenerativas, há avanços promissores e potencialmente interessantes; no entanto, os resultados podem ser considerados incipientes e deve-se assinalar, portanto, que a associação da terapia gênica e celular apresenta-se como uma alternativa possível, mas ainda muito distante quanto à sua consolidação e incorporação como opção terapêutica segura e eficaz em FC. Por outro lado, tendo por embasamento os resultados obtidos em modelos experimentais, é possível postular que a terapia celular com células-tronco hematopoéticas (ou de outras fontes encerra perspectivas consistentes de aplicação em diversas outras patologias pulmonares humanas, especialmente em DPOC.

  4. Mesoporous silica nanoparticles as smart and safe devices for regulating blood biomolecule levels

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yan [Iowa State Univ., Ames, IA (United States)

    2011-01-01

    Stimuli-responsive end-capped MSN materials are promising drug carriers that securely deliver a large payload of drug molecules without degradation or premature release. A general review of the recent progress in this field is presented, including a summary of a series of hard and soft caps for drug encapsulation and a variety of internal and external stimuli for controlled release of different therapeutics, a discussion of the biocompatibility of MSN both in vitro and in vivo, and a description of the sophisticated stimuli-responsive systems with novel capping agents and controlled release mechanism. The unique internal and external surfaces of MSN were utilized for the development of a glucose-responsive double delivery system end-capped with insulin. This unique system consists of functionalized MSNs capable of releasing insulin when the concentration of sugar in blood exceeds healthy levels. The insulin-free nanoparticles are then up taken by pancreatic cells, and release inside of them another biomolecule that stimulates the production of more insulin. The in vivo application of this system for the treatment of diabetes requires further understanding on the biological behaviors of these nanoparticles in blood vessels. The research presented in this dissertation demonstrated the size and surface effects on the interaction of MSNs with red blood cell membranes, and discovered how the surface of the nanoparticles can be modified to improve their compatibility with red blood cells and avoid their dangerous side effects. In order to optimize the properties of MSN for applying them as efficient intracellular drug carriers it is necessary to understand the factors that can regulate their internalization into and exocytosis out of the cells. The correlation between the particle morphology and aggregation of MSNs to the effectiveness of cellular uptake is discussed and compared with different cell lines. The differences in the degree of exocytosis of MSNs between

  5. Real-time monitoring and manipulation of single bio-molecules in free solution

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hung-Wing

    2005-08-01

    The observation and manipulation of single biomolecules allow their dynamic behaviors to be studied to provide insight into molecular genetics, biochip assembly, biosensor design, DNA biophysics. In a PDMS/glass microchannel, a nonuniform electroosmotic flow (EOF) was created. By using a scanning confocal fluorescence microscope and total internal-reflection fluorescence microscope (TIRFM), we demonstrated that negatively charged DNA molecules were focused by the nonuniform EOF into a thin layer at the glass surface. This phenomenon was applied to selectively detect target DNA molecules without requiring the separation of excessive probes and can be applied continuously to achieve high throughput. A variable-angle-TIRFM was constructed for imaging single DNA molecule dynamics at a solid/liquid interface. Implications we have are that the measured intensities cannot be used directly to determine the distances of molecules from the surface and the experimental counting results depict the distance-dependent dynamics of molecules near the surface; Molecules at low ionic strengths experience electrostatic repulsion at distances much further away from the surface than the calculated thickness of the electrical double layer. {delta}-DNA was employed as a nanoprobe for different functionalized surfaces to elucidate adsorption in chromatography. The 12-base unpaired ends of this DNA provide exposed purine and pyrimidine groups for adsorption. Patterns of self-assembled monolayers (SAMs) and patterns of metal oxides are generated. By recording the real-time dynamic motion of DNA molecules at the SAMs/aqueous interface, the various parameters governing the retention of an analyte during chromatographic separation can be studied. Even subtle differences among adsorptive forces can be revealed. Dynamic conformational changes of the prosthetic group, flavin adenine dinucleotide (FAD), in flavoprotein NADH peroxidase, in thioredoxin reductase, and in free solution were monitored

  6. La epistemologia de Michael Polanyi: una perspectiva realista de la ciencia. [Reseña

    OpenAIRE

    Moros, E. (Enrique)

    2005-01-01

    Reseña de Francisco GALLARDO, La epistemologia de Michael Polanyi: una perspectiva realista de la ciencia, Edizioni Universita della Santa Croce («Series Philosophica »), Roma 2004, 347 pp., 17 x 24, ISBN 88-8333-131-1.

  7. COMPORTAMIENTO ORGANIZACIONAL VS. CUENTA DE RESULTADOS. ACERCAMIENTO DESDE UNA PERSPECTIVA SISTÉMICA

    OpenAIRE

    Rodeloy Castellanos Crúz

    2011-01-01

    Explorar la relación existente entre Comportamiento Organizacional y Cuenta de Resultados o eficiencia en general tiene sentido a partir de la propia definición del Comportamiento Organizacional (CO), un campo de estudio que se legitima dada su perspectiva pragmática: el Comportamiento Organizacional se traduce en Resultados.

  8. Estado autoritário pós-64: perspectivas historiográficas

    Directory of Open Access Journals (Sweden)

    Monique Guimarães Cittadino

    2014-08-01

    Full Text Available O presente trabalho discute as perspectivas historiográficas sobre o Estado autoritário pós-1964. Para isso, são analisados livros específicos de Octávio Ianni, Thomas Skidmore, Maria Helena Moreira Alves, Manuel Antonio Garretón e Guillermo O’Donnell.

  9. Tres perspectivas del acoso moral en el trabajo: psicológica, jurisprudencial y preventiva

    OpenAIRE

    Escudero García, Javier

    2015-01-01

    El acoso moral en el trabajo es un fenómeno muy común en las organizaciones empresariales. Lo que se intenta en este trabajo es analizar y estudiar dicho fenómeno desde tres perspectivas completamente distintas pero a la vez interrelacionadas entre si (psicológica, jurisprudencial y preventiva).

  10. Fluorinated graphenes as advanced biosensors - effect of fluorine coverage on electron transfer properties and adsorption of biomolecules

    Science.gov (United States)

    Urbanová, Veronika; Karlický, František; Matěj, Adam; Šembera, Filip; Janoušek, Zbyněk; Perman, Jason A.; Ranc, Václav; Čépe, Klára; Michl, Josef; Otyepka, Michal; Zbořil, Radek

    2016-06-01

    Graphene derivatives are promising materials for the electrochemical sensing of diverse biomolecules and development of new biosensors owing to their improved electron transfer kinetics compared to pristine graphene. Here, we report complex electrochemical behavior and electrocatalytic performance of variously fluorinated graphene derivatives prepared by reaction of graphene with a nitrogen-fluorine mixture at 2 bars pressure. The fluorine content was simply controlled by varying the reaction time and temperature. The studies revealed that electron transfer kinetics and electrocatalytic activity of CFx strongly depend on the degree of fluorination. The versatility of fluorinated graphene as a biosensor platform was demonstrated by cyclic voltammetry for different biomolecules essential in physiological processes, i.e. NADH, ascorbic acid and dopamine. Importantly, the highest electrochemical performance, even higher than pristine graphene, was obtained for fluorinated graphene with the lowest fluorine content (CF0.084) due to its high conductivity and enhanced adsorption properties combining π-π stacking interaction with graphene regions with hydrogen-bonding interaction with fluorine atoms.Graphene derivatives are promising materials for the electrochemical sensing of diverse biomolecules and development of new biosensors owing to their improved electron transfer kinetics compared to pristine graphene. Here, we report complex electrochemical behavior and electrocatalytic performance of variously fluorinated graphene derivatives prepared by reaction of graphene with a nitrogen-fluorine mixture at 2 bars pressure. The fluorine content was simply controlled by varying the reaction time and temperature. The studies revealed that electron transfer kinetics and electrocatalytic activity of CFx strongly depend on the degree of fluorination. The versatility of fluorinated graphene as a biosensor platform was demonstrated by cyclic voltammetry for different biomolecules

  11. Biomolecule-Assisted Hydrothermal Synthesis and Self-Assembly of Bi2Te3 Nanostring-Cluster Hierarchical Structure

    DEFF Research Database (Denmark)

    Mi, Jianli; Lock, Nina; Sun, Ting; Christensen, Mogens; Søndergaard, Martin; Hald, Peter; Hng, Huey H.; Ma, Jan; Iversen, Bo Brummerstedt

    2010-01-01

    A simple biomolecule-assisted hydrothermal approach has been developed for the fabrication of Bi2Te3 thermoelectric nanomaterials. The product has a nanostring-cluster hierarchical structure which is composed of ordered and aligned platelet-like crystals. The platelets are100 nm in diameter and...... template. Subsequently, Bi2Te3 grows in a certain direction on the surface of the Te rods, resulting in the nanostring structure. The nanostrings further recombine side-byside with each other to achieve the ordered nanostring clusters. The particle size and morphology can be controlled by adjusting the...

  12. Development of a combined surface plasmon resonance/surface acoustic wave device for the characterization of biomolecules

    OpenAIRE

    Bender, Florian; Roach, Paul; Tsortos, Achilleas; Papadakis, George; Newton, Michael; McHale, Glen; Gizeli, Electra

    2009-01-01

    It is known that acoustic sensor devices, if operated in liquid phase, are sensitive not just to the mass of the analyte but also to various other parameters, such as size, shape, charge and elastic constants of the analyte as well as bound and viscously entrained water. This can be used to extract valuable information about a biomolecule, particularly if the acoustic device is combined with another sensor element which is sensitive to the mass or amount of analyte only. The latter is true in...

  13. As facções cariocas em perspectiva comparativa

    Directory of Open Access Journals (Sweden)

    Benjamin Lessing

    2008-03-01

    Full Text Available Entre os especialistas em segurança pública, tornou-se lugar-comum a idéia de que a guerra do tráfico no Rio de Janeiro é totalmente única no Brasil. Porém, essa afirmação é imprecisa. Organizações de narcotráfico em muitos aspectos comparáveis às facções cariocas existem em outros contextos urbanos. O que as diferencia é menos a capacidade de estabelecer o monopólio local sobre o comércio de drogas do que a resiliência da sua estrutura interna e, portanto, a duração da sua existência e dominação. Durante uma pesquisa de campo em nove comunidades de periferia de três cidades, observei não apenas uma alta variação nos graus de concentração entre os mercados locais de drogas, mas também de variação com o tempo dentro da mesma comunidade. Desta perspectiva, a estabilidade do mercado de drogas altamente concentrado do Rio de Janeiro pode ser visto como um equilíbrio único, no qual as forças de fragmentação operantes em outras cidades são neutralizadas por características específicas das facções cariocas. O meu argumento é o de que tais características decorrem do domínio exercido pelas facções sobre o sistema penitenciário desde antes do início da sua expansão para o comércio de drogas.It has become a commonplace that Rio de Janeiro’s guerra do tráfico is entirely unique within Brazil. In fact, this is inaccurate. Drug trafficking organizations that in many respects resemble Rio’s facções do exist in other urban contexts. What differentiates them is less the ability to establish a local monopoly on the drug trade than the resilience of their internal structure, and consequently the duration of their existence and domination. During field research in nine peripheral communities in three cities, I observed not only high variation in the degree of concentration between local drug markets, but also variation over time within single communities. In this light, the stability of Rio’s highly

  14. Biomolecule-loaded chitosan nanoparticles induce apoptosis and molecular changes in cancer cell line (SiHa).

    Science.gov (United States)

    Sujima Anbu, Anbu; Velmurugan, Palanivel; Lee, Jeong-Ho; Oh, Byung-Taek; Venkatachalam, Perumal

    2016-07-01

    The present study reports on the synthesis of chitosan nanoparticles (CNPs) using methanol extracts of Gymnema sylvestre (GS) leaves and Cinnamomum zeylanicum (CZ) bark. Biomolecule-loaded nanoparticles induced apoptosis in a human cervical cancer (SiHa) cell line, and experiments were carried out to elucidate the underlying molecular mechanisms. FT-IR and XRD showed possible functional groups of the biomolecules and the crystalline nature of CNPs, respectively. Transmission electron microscopy images revealed that synthesized GSCNPs and CZCNPs had a smooth spherical shape with average sizes of about 58-80 and 60-120nm, respectively. Dynamic light scattering studies indicated that both GSCNPs and CZCNs were structurally stable with homogenous and heterogeneous natures, respectively. Furthermore, synthesized GSCNPs and CZCNPs exhibited dose-dependent cytotoxicity against the SiHa cancer cell line, with inhibitory concentration (IC50) values of 102.17μg/ml, 87.75μg/ml, 132.74μg/ml and 90.35μg/ml for GS leaf extract, GSCNPs, CZBE and CZCNPs, respectively. PMID:27016087

  15. Versatile method for AFM-tip functionalization with biomolecules: fishing a ligand by means of an in situ click reaction

    Science.gov (United States)

    Kumar, Rakesh; Ramakrishna, Shivaprakash N.; Naik, Vikrant V.; Chu, Zonglin; Drew, Michael E.; Spencer, Nicholas D.; Yamakoshi, Yoko

    2015-04-01

    A facile and universal method for the functionalization of an AFM tip has been developed for chemical force spectroscopy (CFS) studies of intermolecular interactions of biomolecules. A click reaction between tripod-acetylene and an azide-linker-ligand molecule was successfully carried out on the AFM tip surface and used for the CFS study of ligand-receptor interactions.A facile and universal method for the functionalization of an AFM tip has been developed for chemical force spectroscopy (CFS) studies of intermolecular interactions of biomolecules. A click reaction between tripod-acetylene and an azide-linker-ligand molecule was successfully carried out on the AFM tip surface and used for the CFS study of ligand-receptor interactions. Electronic supplementary information (ESI) available: Experimental details with synthesis and characterization of compounds. Procedures for modifications of Au surfaces and AFM tips. AFM images and full PM-IRRAS spectra of modified surfaces. Detailed procedure for QCM measurement. A table showing ligand-receptor interaction probability. NMR, IR and MS charts. See DOI: 10.1039/c5nr01495f

  16. The Study of Biomolecule-Substrate Interactions by Single Molecule Force Spectroscopy and Brownian Dynamics Simulations

    Science.gov (United States)

    Cook, Sara Iliafar

    Hybrids of biomolecules and nanomaterials have been identified as promising candidates in the development of novel therapeutics and electronic devices. Single stranded DNA (ssDNA)-bound Single-walled carbon nanotubes (SWCNTs) are of particular interest as they may be the key to solving the challenges that face the carbon nanotube separation technology and because of their potential application in bio-nanomedicine. The ability of ssDNA to form a stable hybrid with CNTs has been attributed to the structure and amphiphilic nature of this macromolecule, enabling the dispersion, sorting and patterned placement of nanotubes. Considering the significant role of ssDNA-CNTs in future technologies and the potential toxicity of such nanomaterials in biological systems, it is essential to gain a quantitative and fundamental understanding on the interactions that allow, weaken or prevent the formation of these hybrids. In this dissertation, we use both experimental and theoretical methods to systematically investigate the major characteristics of these interactions. The free energy of binding of ssDNA homopolymers to solvated carbon nanotubes is one of the key characteristics that determine the stability of such dispersions. We used single molecule force spectroscopy (SMFS), first on graphite and next on single walled carbon nanotubes, to probe and directly quantify the binding strength of ssDNA homopolymer oligomers to these substrates. The force resisting removal of DNA molecules from these surfaces shows characteristic steady-state force plateaus which were distinguishable for each DNA sequence. The free energy of binding per nucleotide for these oligomers on graphite were ranked as T >= A > G >= C (11.3 +/- 0.8 kT, 9.9 +/- 0.4 kT, 8.3 +/- 0.2 kT, and 7.5 +/- 0.8 kT, respectively). On SWCNTs, these interactions decreased in the following order: A > G > T > C, and their magnitude was much larger than on graphite (38.1 +/- 0.2; 33.9 +/- 0.1; 23.3 +/- 0.1; 17.1 +/- 0.1 k

  17. The biophysical effects of deuterium oxide on biomolecules and living cells through open notebook science

    Science.gov (United States)

    Salvagno, Anthony L.

    hydrogen-deuterium exchange was quantified for bulk water with CRDS. Using optical tweezers, DNA was overstretched in both H2O and D2O. The average force for DNA overstretching was found to be ~2.5pN higher in D2O compared to H2O. Deuterium oxide has a stabilizing force on biomolecules, which prevents protein denaturing and can affect the timing for cellular processes. It is because of this molecular property that D2O is observed to affect organisms grown with D2O instead of H2O. Despite this, there seems to be an optimal concentration of deuterium which is above the natural concentration of 155.6ppm. In the presence of deuterium depleted water, cells exhibit signs of stress, further demonstrating that deuterium isn't merely tolerated in solution, but actually required as hypothesized by Gilbert N. Lewis in 1934.

  18. Diferentes perspectivas sobre el estudio de la familia en el norte urbano de Marruecos: un análisis en perspectiva de género

    OpenAIRE

    Elena Hernández Corrochano

    2008-01-01

    Los estudios sobre la familia, desde las diferentes perspectivas que aquí trato, nos muestran no sólo la importancia del parentesco en las relaciones sociales y en la construcción de la identidad de los sujetos, sino que nos indica cómo en sociedades definidas como modernizadas –donde los Estado sólo tienen interés en lcanzar un cambio económico y el acceso a las nuevas tecnologías, olvidándose de las cuestiones sociales, políticas o filosóficas que caracterizan a la modernidad– a mayor indiv...

  19. Sensitivity and Resolution Enhanced Solid-State NMR for Paramagnetic Systems and Biomolecules under Very Fast Magic Angle Spinning

    KAUST Repository

    Parthasarathy, Sudhakar

    2013-09-17

    Recent research in fast magic angle spinning (MAS) methods has drastically improved the resolution and sensitivity of NMR spectroscopy of biomolecules and materials in solids. In this Account, we summarize recent and ongoing developments in this area by presenting (13)C and (1)H solid-state NMR (SSNMR) studies on paramagnetic systems and biomolecules under fast MAS from our laboratories. First, we describe how very fast MAS (VFMAS) at the spinning speed of at least 20 kHz allows us to overcome major difficulties in (1)H and (13)C high-resolution SSNMR of paramagnetic systems. As a result, we can enhance both sensitivity and resolution by up to a few orders of magnitude. Using fast recycling (∼ms/scan) with short (1)H T1 values, we can perform (1)H SSNMR microanalysis of paramagnetic systems on the microgram scale with greatly improved sensitivity over that observed for diamagnetic systems. Second, we discuss how VFMAS at a spinning speed greater than ∼40 kHz can enhance the sensitivity and resolution of (13)C biomolecular SSNMR measurements. Low-power (1)H decoupling schemes under VFMAS offer excellent spectral resolution for (13)C SSNMR by nominal (1)H RF irradiation at ∼10 kHz. By combining the VFMAS approach with enhanced (1)H T1 relaxation by paramagnetic doping, we can achieve extremely fast recycling in modern biomolecular SSNMR experiments. Experiments with (13)C-labeled ubiquitin doped with 10 mM Cu-EDTA demonstrate how effectively this new approach, called paramagnetic assisted condensed data collection (PACC), enhances the sensitivity. Lastly, we examine (13)C SSNMR measurements for biomolecules under faster MAS at a higher field. Our preliminary (13)C SSNMR data of Aβ amyloid fibrils and GB1 microcrystals acquired at (1)H NMR frequencies of 750-800 MHz suggest that the combined use of the PACC approach and ultrahigh fields could allow for routine multidimensional SSNMR analyses of proteins at the 50-200 nmol level. Also, we briefly discuss the

  20. MOBILIZAÇÃO SOCIAL E COMUNICAÇÃO: POR UMA PERSPECTIVA RELACIONAL

    Directory of Open Access Journals (Sweden)

    Rennan Lanna Martins Mafra

    2010-06-01

    Full Text Available Neste artigo, busca-se compreender os processos de mobilização social – movimentos essenciais de organização dos sujeitos em torno de causas sociais – como fenômenos comunicacionais. Para isso, orienta-se por uma perspectiva relacional da comunicação, aqui caracterizada por contribuições de Edgar Morin, Stuart Hall e Louis Queré. Nesse sentido, as discussões aqui empreendidas visam tecer um entendimento sobre tal perspectiva relacional (de modo a caracterizar o viés comunicacional escolhido para, em seguida, buscar instrumentais conceituais que possam alargar a compreensão da mobilização social como um processo comunicativo.

  1. Lealtad de marca: antecedentes y perspectivas de investigación.

    Directory of Open Access Journals (Sweden)

    Julián Ramírez Angulo

    2013-06-01

    Full Text Available Este documento revisa la caracterización de la lealtad de marca, como variable multidimensional del marketing y sus perspectivas para la investigación. Para tal fin, en primer lugar se hace una revisión de los antecedentes conceptuales para, posteriormente, ilustrar la evolución y la tendencia creciente en la investigación sobre el tema. Esto conduce a presentar tres posibles perspectivas de investigación sobre la lealtad, vinculadas a su examen como innovaciones a través de la logística y en el plano del comercio electrónico. El objeto de esta revisión es aproximarse en la elaboración de un estado del arte que soporte el desarrollo de un proyecto de tesis doctoral.

  2. Study of sodium arsenite induced biochemical changes on certain biomolecules of the freshwater catfish Clarias batrachus

    Directory of Open Access Journals (Sweden)

    Randhir Kumar

    2012-01-01

    Full Text Available Toxic impact of sublethal concentration (1 mg/L; 5% of 96h LC50 value of sodium arsenite (NaAsO2 on certain biomolecules (proteins, nucleic acids, lipids, and glycogen of five tissue components (muscles, liver, brain, skin, and gills of the freshwater catfish Clarias batrachus was analysed. The important toxic manifestations include marked decrease in the concentration of proteins (21.72-45.42% in muscles; 3.42-53.94% in liver; 15.39-45.42% in brain; 15.40-4.00% in skin and 11.35-64.13% in gills, DNA (0.55-22.95% in muscles; 8.33-14.06% in liver; 5.30-18.40% in brain; 13.57-52.80% in skin; and 12.38-31.01% in gills, RNA (42.68-76.16% in muscles; 10.68-39.75% in liver; 5.66-29.05% in brain; 7.72-27.93% in skin and 21.47-44.38% in gills and glycogen (24.00-51.72% in muscles; 49.11-72.45% in liver; 11.49-26.03% in brain; 26.13-38.05% in skin and 17.80-37.97% in gills. Excepting liver where the lipid content increases (15.82-24.13%, the fat content also showed depletion in their concentration (10.40-29.83% in muscles; 8.30-34.45% in brain; 8.94-31.47% in skin and 12.75-28.86% in gills, in the rest of the organ systems.Foi analisado o impacto tóxico da concentração subletal (1 mg/L; 5% do valor de LC50 de 96h do arsenito de sódio (NaAsO2 sobre certas biomoléculas (proteinas, ácidos nucleicos, lipídios e glicogênio de cinco tecidos (músculos, fígado, cérebro, pele e brânquias do bagre Clarias batrachus. As manifestações tóxicas importantes incluiram o decréscimo acentuado na concentração de proteinas (21,72-45,42% nos músculos; 3,42-53,94% no fígado; 15,39-45,42% no cérebro; 15,40-4,00% na pele e 11,35-64,13% nas brânquias, DNA (0,55-22,95% nos músculos; 8,33-14,06% no fígado; 5,30-18,40% no cérebro; 13,57-52,80% na pele e 12,38-31,01% nas brânquias, RNA (42,68-76,16% nos músculos; 10,68-39,75% no fígado; 5,66-29,05% no cérebro; 7,72-27,93% na pele e 21,47-44,38% nas brânquias e glicogênio (24,00-51,72% nos músculos; 49

  3. Perspectivas de la personalidad en negociaciones y resolución de conflictos

    Directory of Open Access Journals (Sweden)

    Marhilde Sánchez de Gallardo

    2002-09-01

    Full Text Available El presente artículo destaca los aportes de las teorías psicológicas psicoanalítica, del aprendizaje y fenomenológica del estudio de la personalidad, en el desarrollo de conocimientos y habilidades útiles en la actividad profesional, referentes a la autoevaluación del comportamiento en las negociaciones efectuadas. Se concibe la personalidad como un todo organizado, en funcionamiento conjunto, donde se interrelacionan pensamientos, sentimientos y conductas que generan coherencia a la vida del ser humano. En la perspectiva psicoanalítica, la teoría de Sigmund Freud, la estructura de la personalidad ello, yo y super yo, regidos por los principios del placer, la realidad y la moral respectivamente, se encuentran en interacción dinámica, en su propósito por conducir las actividades del hombre. La perspectiva del aprendizaje se orienta a los factores ambientales que dirigen la conducta. En el condicionamiento operante, se estudian las consecuencias, después de ocurrida una conducta, que aumentan y disminuyen la probabilidad de repetición de dicha conducta. Las teorías del aprendizaje social o cognitivo, conceden elevada importancia a los procesos mentales y a los aspectos sociales del aprendizaje. La perspectiva fenomenológica enfatiza al individuo como un ser activo, creativo, que responde en forma subjetiva a las percepciones, relaciones y encuentros actuales, con tendencias hacia la autorrealización. Cada una de las perspectivas genera una amplia comprensión de la incidencia del capital humanoen las negociaciones.

  4. A perspectiva cognitiva sobre a decisão estratégica

    OpenAIRE

    Cabecinhas, Rosa

    1994-01-01

    Neste artigo efectua-se um breve levantamento da pesquisa no âmbito da perspectiva cognitiva sobre a decisão estratégica e apresenta-se um modelo que ilustra as potencialidades de uma articulação entre a psicologia social e a psicossociologia das organizações através dos processos cognitivos: o modelo de Schwenk (1988).

  5. Ações afirmativas da perspectiva dos direitos humanos Affirmative action from a human rights perspective

    Directory of Open Access Journals (Sweden)

    Flavia Piovesan

    2005-04-01

    Full Text Available Objetiva o artigo desenvolver uma análise a respeito das ações afirmativas sob a perspectiva dos direitos humanos. Inicialmente, trata da concepção contemporânea de direitos humanos, introduzida pela Declaração Universal de 1948, com ênfase na universalidade, indivisibilidade e interdependência dos direitos humanos. Em um segundo momento são apreciadas as ações afirmativas da perspectiva dos direitos humanos, com destaque dos valores da igualdade e diversidade. Por fim, são avaliadas as perspectivas e desafios para a implementação da igualdade étnico-racial na ordem contemporânea.The article aims to develop an analysis on affirmative action from a human rights perspective. Initially, it deals with the contemporary conception of human rights, introduced by the Universal Declaration of 1948, stressing their universality, indivisibility, and interdependence. At a second stage, affirmative action is analyzed from a human rights perspective, stressing the values of egalitarianism and diversity. Finally, the perspectives and challenges to implement ethnic-racial egalitarianism in the contemporary order are assessed.

  6. Shape-controlled synthesis and properties of manganese sulfide microcrystals via a biomolecule-assisted hydrothermal process

    International Nuclear Information System (INIS)

    An effective biomolecule-assisted synthetic route has been successfully developed to prepare γ-manganese sulfide (MnS) microtubes under hydrothermal conditions. In the synthetic system, soluble hydrated manganese chloride was employed to supply Mn source and L-cysteine was used as precipitator and complexing reagent. Sea urchin-like γ-MnS and octahedron-like α-MnS microcrystals could also be selectively obtained by adjusting the process parameters such as hydrothermal temperature and reaction time. The phase structures, morphologies and properties of the as-prepared products were investigated in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersion spectroscopy (EDS), and photoluminescence spectra (PL). The photoluminescence studies exhibited the correlations between the morphology, size, and shape structure of MnS microcrystals and its optical properties. The formation mechanisms of manganese sulfide microcrystals were discussed based on the experimental results.

  7. Oxidative destruction of biomolecules by gasoline engine exhaust products and detoxifying effects of the three-way catalytic converter.

    Science.gov (United States)

    Blaurock, B; Hippeli, S; Metz, N; Elstner, E F

    1992-01-01

    Aqueous solutions of engine exhaust condensation products were derived from cars powered by diesel or four-stroke gasoline engines (with and without three-way catalytic converter). The cars were operated on a static test platform. Samples of the different exhaust solutions accumulated in a Grimmer-type distillation trap (VDI 3872) during standard test programs (Federal Test Procedure) were incubated with important biomolecules. As indicators of reactive oxygen species or oxidative destruction, ascorbic acid, cysteine, glutathione, serum albumin, the enzymes glycerinaldehyde phosphate dehydrogenase and xanthine oxidase, and the oxygen free-radical indicator keto-methylthiobutyrate were used. During and after the incubations, oxygen activation (consumption) and oxidative destruction were determined. Comparison of the oxidative activities of the different types of exhaust condensates clearly showed that the exhaust condensate derived from the four-stroke car equipped with a three-way catalytic converter exhibited by far the lowest oxidative and destructive power. PMID:1283938

  8. Computational methods to study the structure and dynamics of biomolecules and biomolecular processes from bioinformatics to molecular quantum mechanics

    CERN Document Server

    2014-01-01

    Since the second half of the 20th century machine computations have played a critical role in science and engineering. Computer-based techniques have become especially important in molecular biology, since they often represent the only viable way to gain insights into the behavior of a biological system as a whole. The complexity of biological systems, which usually needs to be analyzed on different time- and size-scales and with different levels of accuracy, requires the application of different approaches, ranging from comparative analysis of sequences and structural databases, to the analysis of networks of interdependence between cell components and processes, through coarse-grained modeling to atomically detailed simulations, and finally to molecular quantum mechanics. This book provides a comprehensive overview of modern computer-based techniques for computing the structure, properties and dynamics of biomolecules and biomolecular processes. The twenty-two chapters, written by scientists from all over t...

  9. A TiS2 nanosheet enhanced fluorescence polarization biosensor for ultra-sensitive detection of biomolecules

    Science.gov (United States)

    Li, Xiang; Ding, Xuelian; Li, Yongfang; Wang, Linsong; Fan, Jing

    2016-05-01

    Development of new strategies for the sensitive and selective detection of ultra-low concentrations of specific cancer markers is of great importance for assessing cancer therapeutics due to its crucial role in early clinical diagnoses and biomedical applications. In this work, we have developed two types of fluorescence polarization (FP) amplification assay strategies for the detection of biomolecules by using TiS2 as a FP enhancer and Zn2+-dependent self-hydrolyzing deoxyribozymes as catalysts to realize enzyme-catalyzed target-recycling signal amplification. One approach is based on the terminal protection of small-molecule-linked DNA, in which biomolecular binding to small molecules in DNA-small-molecule chimeras can protect the conjugated DNA from degradation by exonuclease I (Exo I); the other approach is based on the terminal protection of biomolecular bound aptamer DNA, in which biomolecules directly bound to the single strand aptamer DNA can protect the ssDNA from degradation by Exo I. We select folate receptor (FR) and thrombin (Tb) as model analytes to verify the current concept. It is shown that under optimized conditions, our strategies exhibit high sensitivity and selectivity for the quantification of FR and Tb with low detection limits (0.003 ng mL-1 and 0.01 pM, respectively). Additionally, this strategy is a simple ``mix and detect'' approach, and does not require any separation steps. This biosensor is also utilized in the analysis of real biological samples, the results agree well with those obtained by the enzyme-linked immunosorbent assay (ELISA).Development of new strategies for the sensitive and selective detection of ultra-low concentrations of specific cancer markers is of great importance for assessing cancer therapeutics due to its crucial role in early clinical diagnoses and biomedical applications. In this work, we have developed two types of fluorescence polarization (FP) amplification assay strategies for the detection of biomolecules

  10. Energy transfer mechanisms in photobiological reactions. Final report, 1 April 1960--31 March 1979. [Photodynamic processes in selected biomolecules

    Energy Technology Data Exchange (ETDEWEB)

    Spikes, J.D.

    1979-03-31

    This project was concerned primarily with studies of the mechanisms of the sensitized photooxidation of selected biomolecules using a variety of phtosensitizers. Such reactions are often termed photodynamic processes. In particular we have carried out steady-state kinetic studies, flash photolysis and spectral studies, and product formation studies of the sensitized photooxidation of the five susceptible amino acids (cycteine, histidine, methonine, tryptophan, and tyrosine) and their derivatives, as well as purines and pyrimidines. A number of studies were also carried out on the mechanisms of the photodynamic inactivation of enzymes (trypsin, ribonuclease, lysozyme). Mechanism of photosensitization were studied using a variety of sensitizers including flavins, porphyrins, and a number of synthetic dyes (substituted fluoresceins, acridines, thyazines).

  11. Fabrication of non-enzymatic biosensor based on metallic catalyst-TiO2 hollow sphere nanocomposite for determining biomolecules.

    Science.gov (United States)

    Kwen, Hai-Doo; Yang, Hee-Soo; Lee, In-Ho; Choi, Seong-Ho

    2012-07-01

    A PtRu@TiO2-hollow nanocomposite for the detection of biomolecules was synthesized by chemical reduction. First, poly(styrene-co-vinylphenylboronic acid), PSB, was prepared as a template (approximately 250 nm) by surfactant-free emulsion polymerization. Second, PSB/TiO2 core-shell spheres were prepared by sol-gel reaction. Finally, TiO2 hollow spheres (TiO2-H) were then formed after removing the PSB template by calcination at 450 degrees C under air atmosphere. To prepare the electrocatalyst, PtRu nanoparticles (NPs) were deposited onto the TiO2-H surface by chemical reduction. The prepared PtRu@TiO2-H nanocomposite was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and elemental analysis. A non-enzymatic sensor was fabricated by depositing the as-prepared PtRu@TiO2-H nanocomposite on the surface of a glassy carbon electrode (GCE), which was prepared by a hand casting method with Nafion solution as a binder. The sensor was tested as a biomolecule sensor, especially for the detection of glucose and dopamine. The cyclic voltammograms (CV) obtained during the oxidation studies revealed that the PtRu@TiO2-H nanocomposite showed better catalytic function toward the oxidation of dopamine. The sensing range of the non-enzymatic sensor for glucose was 5.0-100 mM in a phosphate buffer. The results demonstrated the potential usefulness of this bimetallic@TiO2-H bifunctional catalyst for biosensor applications. PMID:22966548

  12. Very stable 188Re-S4 chelates for labelling biomolecules. Preparation with highly concentrated perrhenate eluates

    International Nuclear Information System (INIS)

    Aim: The preparation and stability of a new 188Re-S4-complex [S4 (1-aza-18-crown-6)(O)C-C(SH)-C(SH)-C(O)NH-(CH2)3-NH-(CH2)3-NHC(O)- = C(SH)- C(SH )-C(O)(1-aza-18-crown-6)] was studied at therapeutic relevant radioactive concentrations. The results were compared with 188Re-MAG3 (MAG3: mercaptoacetyltriglycine) and 188Re-DMSA preparations (DMSA: dimercaptosuccinic acid) performed with the same highly concentrated [188Re]perrhenate solution (12-15 GBq/ml). Methods: The 188Re complexes were prepared by direct reduction of perrhenate (188Re-S4-complex) as well as via the 188Re-EDTA precursor complex (188Re-MAG3, 188Re-DMSA). The preparations were stabilised with 15 mg of ascorbic acid and analysed after 1, 2, and 24 hours by TLC and HPLC. Additionally, in vitro and in vivo stability studies were performed with the purified complexes. Results: After stabilisation with 15 mg of ascorbic acid, all of the complexes were nearly stable under nitrogen for hours, and only 2-8% of perrhenate was observed after 24 h. In contrast, only the 188Re-S4 complex was completely stable in vitro and in all investigated in vivo samples after separation of ligand excess and reducing agent by HPLC. Conclusion: The bridging amine group or free carboxylic groups of the S4-ligand framework make available reactive positions for coupling biomolecules to the chelate. Thus it appears that the new 188Re-S4 complexes offer the possibility of stable and high specific activity labelling of biomolecules for therapeutic application. (orig.)

  13. LA PERSPECTIVA DE LOS PARTICIPANTES EN LA PRODUCCIÓN Y ANÁLISIS DE LA INFORMACIÓN DE LA INVESTIGACIÓN CUALITATIVA

    OpenAIRE

    Tójar Hurtado, Juan Carlos

    2013-01-01

    En las siguientes páginas se va a ir analizando el rol de los participantes a partir de la perspectiva de los implicados. Dicha perspectiva que por supuesto es “subjetiva”, no debe ser en ningún caso desdeñada por arbitraria o improcedente. Como se verá, esa perspectiva, con sus motivaciones e inquietudes es la que nos interesa para comprender mejor el mundo que les/nos rodea. Para aproximarnos a esa perspectiva existen numerosos métodos y técnicas. De entre ellas vamos a destacar algunas de ...

  14. Microspheres Assembled from Chitosan-Graft-Poly(lactic acid) Micelle-Like Core-Shell Nanospheres for Distinctly Controlled Release of Hydrophobic and Hydrophilic Biomolecules.

    Science.gov (United States)

    Niu, Xufeng; Liu, Zhongning; Hu, Jiang; Rambhia, Kunal J; Fan, Yubo; Ma, Peter X

    2016-07-01

    To simultaneously control inflammation and facilitate dentin regeneration, a copolymeric micelle-in-microsphere platform is developed in this study, aiming to simultaneously release a hydrophobic drug to suppress inflammation and a hydrophilic biomolecule to enhance odontogenic differentiation of dental pulp stem cells in a distinctly controlled fashion. A series of chitosan-graft-poly(lactic acid) copolymers is synthesized with varying lactic acid and chitosan weight ratios, self-assembled into nanoscale micelle-like core-shell structures in an aqueous system, and subsequently crosslinked into microspheres through electrostatic interaction with sodium tripolyphosphate. A hydrophobic biomolecule either coumarin-6 or fluocinolone acetonide (FA) is encapsulated into the hydrophobic cores of the micelles, while a hydrophilic biomolecule either bovine serum albumin or bone morphogenetic protein 2 (BMP-2) is entrapped in the hydrophilic shells and the interspaces among the micelles. Both hydrophobic and hydrophilic biomolecules are delivered with distinct and tunable release patterns. Delivery of FA and BMP-2 simultaneously suppresses inflammation and enhances odontogenesis, resulting in significantly enhanced mineralized tissue regeneration. This result also demonstrates the potential for this novel delivery system to deliver multiple therapeutics and to achieve synergistic effects. PMID:26987445

  15. Unraveling low-resolution structural data of large biomolecules by constructing atomic models with experiment-targeted parallel cascade selection simulations

    Science.gov (United States)

    Peng, Junhui; Zhang, Zhiyong

    2016-07-01

    Various low-resolution experimental techniques have gained more and more popularity in obtaining structural information of large biomolecules. In order to interpret the low-resolution structural data properly, one may need to construct an atomic model of the biomolecule by fitting the data using computer simulations. Here we develop, to our knowledge, a new computational tool for such integrative modeling by taking the advantage of an efficient sampling technique called parallel cascade selection (PaCS) simulation. For given low-resolution structural data, this PaCS-Fit method converts it into a scoring function. After an initial simulation starting from a known structure of the biomolecule, the scoring function is used to pick conformations for next cycle of multiple independent simulations. By this iterative screening-after-sampling strategy, the biomolecule may be driven towards a conformation that fits well with the low-resolution data. Our method has been validated using three proteins with small-angle X-ray scattering data and two proteins with electron microscopy data. In all benchmark tests, high-quality atomic models, with generally 1–3 Å from the target structures, are obtained. Since our tool does not need to add any biasing potential in the simulations to deform the structure, any type of low-resolution data can be implemented conveniently.

  16. Facile synthesis of Ag dendrites on Al foil via galvanic replacement reaction with [Ag(NH3)2]Cl for ultrasensitive SERS detecting of biomolecules

    International Nuclear Information System (INIS)

    Symmetric silver dendrites have been synthesized on commercial aluminum foil via galvanic replacement reaction with [Ag(NH3)2]Cl. This process is facile and environmentally friendly, without the use of any templates, surfactants or oxidants, and also avoiding the introduction of fluoride anions as a strong toxicity resulting in hypocalcemia. The products were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM) and X-ray diffraction (XRD). SEM characterizations and electrochemical measurements including an electrochemical direct current polarization method and OCP-t technique demonstrate that chloride has proven to be the key factor to the formation of well-defined dendritic shape. The as-prepared Ag dendrites are developed as a surface-enhanced Raman scattering (SERS)-active platform for detection of folic acid, DNA and RNA with well resolved bands and high Raman intensities. The detection concentration for the three biomolecules reaches the level of 10−12 M, and thus the symmetric silver dendrites can potentially be employed as effective SERS sensors for label-free and ultrasensitive biomolecule detection. - Highlights: • Simple galvanic replacement is used to synthesize Ag dendrites on commercial Al foils. • This method avoids the introduction of fluoride anions. • The as-prepared dendrites exhibit high SERS activities for biomolecules. • The detection concentration for the biomolecules reaches the level of 10−12 M

  17. Electron impact total ionization cross sections for simple bio-molecules (H2CO, HCOOH and CH3COOH) using ICSP-ic method

    International Nuclear Information System (INIS)

    In the present work we compute total ionization cross sections for simple bio-molecules viz. formaldehyde, formic acid and acetic acid on electron impact. The total ionization cross sections are extracted from total inelastic cross section using Improved Complex Scattering Potential-ionization contribution method.

  18. Biomolecule-assisted exfoliation and dispersion of graphene and other two-dimensional materials: a review of recent progress and applications.

    Science.gov (United States)

    Paredes, J I; Villar-Rodil, S

    2016-08-25

    Direct liquid-phase exfoliation of layered materials by means of ultrasound, shear forces or electrochemical intercalation holds enormous promise as a convenient, cost-effective approach to the mass production of two-dimensional (2D) materials, particularly in the form of colloidal suspensions of high quality and micrometer- and submicrometer-sized flakes. Of special relevance due to environmental and practical reasons is the production of 2D materials in aqueous medium, which generally requires the use of certain additives (surfactants and other types of dispersants) to assist in the exfoliation and colloidal stabilization processes. In this context, biomolecules have received, in recent years, increasing attention as dispersants for 2D materials, as they provide a number of advantages over more conventional, synthetic surfactants. Here, we review research progress in the use of biomolecules as exfoliating and dispersing agents for the production of 2D materials. Although most efforts in this area have focused on graphene, significant advances have also been reported with transition metal dichalcogenides (MoS2, WS2, etc.) or hexagonal boron nitride. Particular emphasis is placed on the specific merits of different types of biomolecules, including proteins and peptides, nucleotides and nucleic acids (RNA, DNA), polysaccharides, plant extracts and bile salts, on their role as efficient colloidal dispersants of 2D materials, as well as on the potential applications that have been explored for such biomolecule-exfoliated materials. These applications are wide-ranging and encompass the fields of biomedicine (photothermal and photodynamic therapy, bioimaging, biosensing, etc.), energy storage (Li- and Na-ion batteries), catalysis (e.g., catalyst supports for the oxygen reduction reaction or electrocatalysts for the hydrogen evolution reaction), or composite materials. As an incipient area of research, a number of knowledge gaps, unresolved issues and novel future

  19. Libertad de expresión y el caso del lenguaje del odio. Una aproximación desde la perspectiva norteamericana y la perspectiva alemana

    Directory of Open Access Journals (Sweden)

    Oscar Pérez de la Fuente

    2010-12-01

    Full Text Available Resumen Este artículo analiza las concepciones sobre la libertad de expresión en el caso del lenguaje del odio, centrándose en algunos aspectos de la perspectiva norteamericana y en algunos aspectos de la perspectiva alemana. El primer modelo está basado en la libertad negativa y se corresponde con la visión del mercado de las ideas que ha elaborado la jurisprudencia de la Corte Suprema norteamericana. Este Tribunal ha otorgado una papel prioritario a la libertad de expresión, que debería limitarse sólo en casos de un peligro claro y presente o amenaza de desordenes públicos. El segundo modelo, centrado en la libertad positiva, otorga un papel prioritario a la dignidad humana frente a la libertad de expresión. El Tribunal Constitucional Federal alemán ha considerado que en el conflicto de derechos fundamentales debe establecerse una ponderación según las circunstancias de caso concreto. Abstract This article analyzes the conceptions on freedom of expression in the case of hate speech, focusing in some aspects of the North American perspective and in some aspects of the German perspective. The first model is based on negative freedom and it corresponds with the vision of marketplace of ideas that has elaborated the jurisprudence of the North American Supreme Court. This Court has given a priority role to the free speech that only must be limited in cases of clear and present danger or a threat of the breach of the peace. The second model is focused in the positive freedom, it gives a priority role to the human dignity in front of free speech. The Federal Constitutional Court has established that the conflict between fundamental rights must be considered according to the circumstances of the specific case. 

  20. PRÁCTICAS GERENCIALES ASOCIADAS A LA EVOLUCIÓN DE LAS PERSPECTIVAS DEL CUADRO DE MANDO INTEGRAL

    Directory of Open Access Journals (Sweden)

    Neyda Ibáñez

    2016-05-01

    Full Text Available El trabajo interpreta la vinculación entre la evolución de las diversas perspectivas del Cuadro de Mando Integral (CMI con las diferentes prácticas gerenciales emergentes de los cambios paradigmáticos en las ciencias gerenciales. El estudio se aborda desde la perspectiva hermenéutica en un contexto teórico enunciativo y documental. Se concluye que las perspectivas del CMI y sus prácticas están sujetas a la realidad dinámica, interactiva, mutante, por cuanto su esencia viene a ser la práctica social, la acción humana, la innovación y creatividad.

  1. Aportes a las relaciones entre pensamiento y lenguaje: una perspectiva vygotskyana

    OpenAIRE

    Gómez Martínez, Leonardo

    2011-01-01

    El trabajo busca rastrear el significado de los términos ―pensamiento‖ y ―lenguaje‖ desde una perspectiva vygotskyana y establecer las posibles relaciones entre los procesos del pensamiento y el lenguaje en los simios y el hombre. La idea general es hacer viable la tesis de Vygotsky según la cual el lenguaje es el instrumento indispensable para convertir las funciones psicológicas elementales en funciones psicológicas superiores. Desde este punto de vista, la investigación se dedica a mostrar...

  2. Psicologia e psicologia clínica em Hong-Kong: Perspectivas gerais

    OpenAIRE

    Santos, Teresa

    1989-01-01

    A autora procura situar o fenómeno de edificação da Psicologia como ciência, e da Psicologia Clínica enquanto ramo dessa mesma ciência, no território de Hong-Kong. A referência ao contexto sócio-cultural em que o mesmo se desenrola, bem como a aspectos psicológicos inerentes à população de etnia chinesa, visa fornecer uma perspectiva de análise dinâmica desse mesmo fenómeno. ------ ABSTRACT ------ Concerning the territory of Hong-Kong the author describes the Psycho...

  3. Abordagem do capital intelectual na perspectiva da tridimensionalidade da linguagem contábil

    OpenAIRE

    BEUREN, Ilse Maria; COLAUTO, Romualdo Douglas

    2004-01-01

    O artigo aborda o capital intelectual na perspectiva da tridimensionalidade da linguagem contábil. Para tanto, foi realizada pesquisa exploratória em fontes secundárias, com abordagem lógica dedutiva. O trabalho busca preencher uma lacuna existente na literatura quanto à necessidade de se considerar os elementos intangíveis, em particular, os relacionados ao capital intelectual, no processo de mensuração dos ativos das organizações. Inicialmente, faz uma incursão na conceituação e característ...

  4. Arqueologia de la mort: una perspectiva de la història medieval

    OpenAIRE

    Ollich i Castanyer, Imma, 1951-

    1993-01-01

    El tema que presentem avui pretén enfocar una 'arqueologia de la mort' entesa com una perspectiva de (i per) la història medieval. Més que enfocar tipologies d'enterraments, sepultures i esquelets, i la seva evolució en les diferents cultures que es desenvolupen al llarg de l'Edat Mitjana (tasca que han fet els meus companys en els conferències dels dies precedents), m'agradaria intentar una teorització sobre què suposa fer arqueologia centrada en un aspecte concret de les restes materials: l...

  5. UNA PERSPECTIVA HETERODOXA SUGERIDA PARA EL ESTUDIO DE LAS EMPRESAS FAMILIARES EN COLOMBIA

    OpenAIRE

    RUTH ESPERANZA ROMÁN CASTILLO

    2009-01-01

    A partir de la revisión de fuentes secundarias en forma de libros, artículos y trabajos de grado, y con propósitos de reflexión y evaluación, en este artículo se identifican algunas tendencias ortodoxas de la investigación nacional sobre las empresas familiares, y un grupo de perspectivas heterodoxas señaladas por investigadores del mundo anglosajón. Los resultados de la revisión permiten concluir la alta difusión de las teorías ortodoxas entre investigadores y estudiantes; mientras que, los ...

  6. Supervisão parental numa perspectiva de segurança infantil

    OpenAIRE

    Andrade, Maria da Conceição Braga Vieira de

    2014-01-01

    Doutoramento em Motricidade Humana na especialidade de Comportamento Motor Esta dissertação aborda a supervisão parental numa perspectiva de segurança infantil. O percurso da tese inclui a tradução, adaptação e validação de um dos instrumentos mais divulgados para estudar a supervisão parental: o Parental Supervision Attributes Profile Questionnaire (PSAPQ)(Morrongiello & House, 2004; Morrongiello & Corbett, 2006). Foi feita a tradução, adaptação cultural e validação do instrumento e m...

  7. La subjetividad en una perspectiva cultural-histórica: avanzando sobre un legado inconcluso

    OpenAIRE

    Fernando Luis González Rey

    2013-01-01

    En el presente artículo se pretende mostrar cómo las transformaciones del psiquismo humano, a partir del carácter cultural de las producciones y prácticas del hombre, permiten retomar el tema de la subjetividad como nivel cualitativo distintivo de la especie humana. La subjetividad, entendida en la perspectiva aquí defendida, es un proceso inherente al funcionamiento cultural del hombre y al mundo social generado por sus producciones culturales. Estas consideraciones pretenden responder a la ...

  8. Abordaje de un caso clínico tratado desde una perspectiva integradora

    OpenAIRE

    Montes-Berges, Beatriz; Moreno Ratia, Mª Victoria

    2011-01-01

    Este trabajo tiene como objetivo presentar la eficacia de una terapia de integración. Esto supone ir más allá de los límites de los enfoques de escuelas únicas, integrando técnicas y descubrimientos que aunque en principio pueden parecer, en determinadas ocasiones, incompatibles a nivel teórico, resultan enriquecedores en la práctica clínica. Desde esta perspectiva, se ha llevado a cabo el tratamiento de una usuaria adscrita al programa de Violencia de Género, dada la gran vari...

  9. La evaluación de la docencia en lenguaje musical desde una perspectiva integradora

    OpenAIRE

    Esteve-Faubel, José-María; Molina Valero, Miguel Ángel; Botella Quirant, María Teresa; Espinosa Zaragoza, Juan Antonio; Esteve Faubel, Rosa Pilar

    2010-01-01

    Póster y comunicación presentados en las VIII Jornadas de Redes de Investigación en Docencia Universitaria "Nuevas titulaciones y cambio universitario", Alicante, 8-9 Julio 2010. El presente estudio tiene como objetivo evaluar la docencia en la asignatura de Lenguaje Musical, titulación de Magisterio especialidad Musical, desde una perspectiva amplia y combinando tanto el método cualitativo como cuantitativo como medio para conocer con la mayor profundidad posible el tema tratado. Dada la ...

  10. Gestion de indicadores en proyectos de software. Perspectivas actuales y futuras

    Directory of Open Access Journals (Sweden)

    Ramsés Delgado Martínez

    2011-10-01

    Full Text Available Se abordan las temáticas sobre la obtención de medidas e indicadores, así como modelos y herramientas surgidas a lo largo de las últimas décadas en torno a la medición de los procesos y construcción de productos de software, perspectivas actuales y futuras. El contenido servirá de apoyo para la conformación y despliegue del proceso de Medición y Análisis en el marco del Programa de Mejoras que lleva a cabo la Universidad de las Ciencias Informáticas (UCI.

  11. Em busca de uma ética ambiental: as perspectivas e Baird Callicott e Paul Taylor

    OpenAIRE

    Tânia Aparecida Kuhnen

    2012-01-01

    http://dx.doi.org/10.5007/1677-2954.2008v7n3p19O tema deste artigo é a ética ambiental e, mais especificamente, as propostas éticas de Baird Callicott e Paul Taylor, formuladas na tentaiva de expandir a comunidade moral. Enquanto Calliott defende uma perspectiva holista de ética ambiental, na qual o valor moral da ação depende de quanto ela constribui para o bem da comunidade bioética em sua totalidade, Taylor apresenta como moralmente relevantes as ações que contribuem para promover ou prote...

  12. El cine desde la perspectiva de la ciencia pol??tica

    OpenAIRE

    Trenzado Romero, Manuel

    2000-01-01

    La cultura de masas es probablemente uno de los fen??menos peculiares m??s importantes del siglo XX que menos atenci??n han recibido desde la perspectiva de la Ciencia Pol??tica. En este art??culo indagamos en primer lugar en los motivos que han podido motivar este desinter??s politol??gico por la cultura de masas en general y, en particular, por el cine, uno de sus m??s claros exponentes. En el ep??grafe segundo damos cuenta de la manera en que la disciplina de la Comunicaci??n Pol??tica, ye...

  13. La violencia escolar en Colombia desde la perspectiva sistémica de Talcott Parsons

    OpenAIRE

    Palomino-Leiva, Martha Liliana

    2015-01-01

    El eje central de esta investigación es estudiar el fenómeno de la violencia escolar a partir de la teoría sociológica de Talcott Parsons. Desde esta perspectiva la violencia escolar se entiende como una conducta desviada de los escolares motivada por actitudes, valores, normas sociales, creencias y actos simbólicos, manifiestos en su vida cotidiana. Estudio cuantitativo de tipo descriptivo realizado sobre una fuente secundaria, una encuesta oficial, aplicada en la ciudad de Bo...

  14. Los laboratorios de enseñanza desde una perspectiva histórica y social

    OpenAIRE

    Santilli Traba, H.

    2009-01-01

    A partir de un estudio de caso (Física en Ingeniería), se indaga la evolución de los laboratorios de enseñanza, desde el marco de las olas históricas. El enfoque es cualitativo, holístico e interpretativo, se analizan procesos desde la perspectiva de los actores sociales involucrados. Se identifican los cambios en los objetivos y actividades planteados, con miras a desarrollar los conocimientos, científico e ingenieril, de los estudiantes. Se reconocen los cambios en los modelos de ciencia y ...

  15. Perspectivas y proyección profesional de la comunicación social

    OpenAIRE

    Mónica Salazar Gómez; Roberto Sepúlveda

    2011-01-01

    Este artículo pretende conocer y hacer un análisis de las diferentes perspectivas que tienen estudiantes, académicos, empresarios y autoridades educativas acerca del devenir de la carrera de comunicación social. Nos interesa contrastar las diferentes miradas sobre la proyección de la comunicación social, las diversas posturas sobre el deber ser de la carrera, las expectativas frente a lo que debe saber hacer un comunicador social y el devenir de la profesión en relación con las necesida...

  16. Nanotubos de carbono aplicados às neurociências: perspectivas e desafios

    OpenAIRE

    Virginia Oliveira; Michele Munk Pereira; Humberto de Mello Brandão; Marcos Antônio Fernandes Brandão; Wagner Farid Gattaz; Nádia Rezende Barbosa Raposo

    2011-01-01

    INTRODUÇÃO: Os nanotubos de carbono (NTCs) são os nanomateriais mais promissores para aplicação terapêutica em doenças neurodegenerativas. Aplicações potenciais incluem sistemas de liberação controlada de fármacos, interfaces elétricas e substratos para crescimento celular. OBJETIVO: Descrever o estado da arte e as perspectivas e desafios da aplicação dos NTCs nas neurociências. MÉTODO: Procedeu-se a uma busca sistemática nos indexadores Medline, Lilacs e SciELO, utilizando os descritores "ca...

  17. La generalización de patrones desde una perspectiva semiótico-cultural

    OpenAIRE

    Gómez, John; Vergel, Rodolfo

    2012-01-01

    En esta ponencia se presenta un avance de la tesis de maestría “El pensamiento algebraico desde una perspectiva semiótico - cultural. Un trabajo con sucesiones de números reales” que se viene desarrollando en la Maestría en Docencia de las Matemáticas de la Universidad Pedagógica Nacional. Se presenta el análisis hecho a uno de los grupos objeto de la investigación utilizando como marco de referencia el enfoque semiótico - cultural propuesto por Radford (2008, 2009, 2010) sobre el pensamiento...

  18. Los sueños: su estudio científico desde una perspectiva interdisciplinaria

    OpenAIRE

    Maria Claudia Munévar; Andrés Manuel Pérez; Eugenia Guzmán

    1995-01-01

    En las últimas décadas, diversas disciplinas científicas han ganado terreno en el estudio de los sueños, principalmente la antropología, las neurociencias y la psicología, al igual que subdisciplinas como la cronobiología y la somnología. En este artículo se presentan algunas líneas de investigación sobre el tema de una perspectiva interdisciplinaria, incluyendo estudios transculturales, la relación entre el dormir y el soñar, la ontogenia, las clases de sueños y el análisis fo...

  19. BIODIVERSIDADE E PROPRIEDADE INTELECTUAL: UMA PERSPECTIVA SOBRE APROPRIAÇÃO DO CONHECIMENTO DOS POVOS TRADICIONAIS

    OpenAIRE

    Jerônimo Siqueira Tybusch; Thiago Luiz Rigon de Araujo; Letícia Thomasi Jahnke

    2013-01-01

    O presente artigo tem por objetivo abordar além da questão da Propriedade Intelectual e sua definição e seu regime, mas também busca um enfoque especial no campo da biodiversidade, que gera perspectivas de expansão econômica dos países desenvolvidos do norte, outorgados pelos interesses das grandes empresas transnacionais, a partir da exploração e apropriação dos recursos naturais prospectados na vasta biodiversidade dos países pobres e subdesenvolvidos, prática a qual pode ser denominada bio...

  20. Projecto de marketing digital para a APC numa perspectiva de estratégia de desenvolvimento

    OpenAIRE

    Cavez, Ana Lúcia da Silva Pereira

    2014-01-01

    Mestrado em Marketing A tese constante neste documento consiste no desenvolvimento de um plano de marketing digital para uma empresa portuguesa de fabrico de instrumentos cordofones, a APC, numa perspectiva de estratégia de desenvolvimento. Actualmente a empresa, por não possuir pessoal com formação especializada para o efeito, não gere da melhor forma a sua actuação digital, podendo até considerar-se que a sua presença nesse campo é nula ou praticamente inexistente. Apesar de estar pre...

  1. Por uma perspectiva social e política de Gênero e sexualidade.

    OpenAIRE

    Guasch, Òscar, 1961-

    2014-01-01

    Resumo Neste artigo, o sociólogo espanhol Oscar Guasch problematiza as categorias gênero e sexualidade a partir de uma perspectiva social e política. O autor defende que as Ciências Sociais produzam suas próprias ferramentas críticas que possam desmontar e revisar as concepções de gênero e de sexualidade inventadas pelas ciências da saúde (Medicina) e da conduta (Psicologia). Tal abordagem insere-se no campo da Sociologia da Sexualidade na Espanha, no qual Guasch desenvolve suas pesquisas sob...

  2. A maior dor do mundo: o luto materno em uma perspectiva fenomenológica

    OpenAIRE

    Joanneliese Lucas de Freitas; Luís Henrique Fuck Michel

    2014-01-01

    O presente trabalho busca refletir sobre a vivência do luto materno na sociedade brasileira contemporânea, a partir da perspectiva fenomenológico-existencial. Foi realizada uma pesquisa qualitativa com três mães enlutadas. Utilizou-se o método fenomenológico de entrevistas, com uso de pergunta disparadora. A análise dos dados seguiu os quatro passos metodológicos de Giorgi. O relato das mães evidenciou diferentes temáticas, descritas por meio de dez elementos constituintes da vivência de luto...

  3. Una perspectiva lingüística del desarrollo rural regional

    OpenAIRE

    Willelmira Castillejos López

    2009-01-01

    Este estudio está basado en el análisis de un corpus automatizado analizado mediante las herramientas del programa Wordsmith, diseñado para análisis léxico. Los textos que almacena el programa son resultado de 76 ponencias presentadas en el III Congreso Internacional Perspectivas del Desarrollo Rural Regional. El énfasis es en los términos definidos como unidades léxicas especializadas que contribuyen a un mejor entendimiento de las ciencias. El marco teórico es la terminología como referente...

  4. Aproximación a los contextos en prisión. Una perspectiva socioeducativa

    OpenAIRE

    Añaños-Bedriñana, Fanny T.; Fernández-Sánchez, Mª Pilar; Llopis Llácer, Juan José

    2013-01-01

    [ES] Los establecimientos penitenciarios de cumplimiento de pena no sólo son entidades arquitectónicas, administrativas y funcionales del sistema penitenciario, sinoque son contextos ecosistémicos, de socialización y de educación-reeducación de gran importancia, especialmentepara laspersonas internadas. En este trabajo se hace una aproximación a la realidad penitenciaria española, desde una perspectiva socioeducativa de género y, prestando especial atención a la configuracióndel s...

  5. Calidad y desarrollo profesional del profesorado universitario, desde la perspectiva de las comunidades de aprendizaje

    OpenAIRE

    Merma Molina, Gladys; Gavilán Martín, Diego

    2014-01-01

    En esta investigación, reflexionamos en torno a las competencias docentes que debe tener el profesor universitario desde la perspectiva de las comunidades de aprendizaje, en cada una de las etapas de la gestión del proceso de enseñanza-aprendizaje: 1) planificación y diseño de la docencia, donde se plantean competencias y objetivos, se organizan los contenidos, se eligen los materiales y recursos, y se formula la evaluación; 2) la puesta en acción de lo planificado, previamente (metodología y...

  6. Violencia de género en la familia: perspectiva jurídico penal

    OpenAIRE

    José Julio Nares Hernández; Dulce Gloria Martínez García; Ricardo Colín García

    2015-01-01

    Se analizan desde una perspectiva garantista la Constitución Federal y los tratados internacionales que obligan al Estado a tutelar penalmente el derecho humano de la mujer a una vida libre de violencia en el hogar. Se concluye que para cumplir con este deber es ineludible la creación legislativa de tipo penal que sancione la violencia familiar asociada a la violencia de género. Esta acción legislativa sería parte de una nueva política criminológica dedicada específicamente a la prevención, s...

  7. Autocuidado de diabetes: una mirada con perspectiva de género

    OpenAIRE

    Laura Elena Trujillo Olivera; Austreberta Nazar Beutelspacher

    2011-01-01

    En Tuxtla Gutiérrez, Chiapas, se realizó un estudio cualitativo encaminado a explorar con perspectiva de género las relaciones intergenéricas en grupos domésticos y su influencia en el autocuidado de personas diabéticas. La información emPírica provino de entrevistas en profundidad a algunos enfermos y a una persona cercana. En este caso se propone una categorización de autocuidado basada en lo que ellos manifiestan que hacen para controlar la enfermedad. Se documenta una importante desiguald...

  8. Una perspectiva neurocientífica sobre la histeria / a neuroscientific approach to hysteria

    OpenAIRE

    Amoruso, Lucía

    2010-01-01

    En la última década, el desarrollo y la puesta en marcha de las modernas técnicas de neuroimagen en el campo de la neurociencia cognitiva han proporcionado una nueva vía de acercamiento al estudio experimental de algunos trastornos mentales. Dentro de esta perspectiva, denominada por algunos autores “neuropsiquiatría cognitiva”, la histeria (o trastorno de conversión, de acuerdo con la clasificación psiquiátrica actual) ha cobrado un amplio protagonismo. De acuerdo con lo anterior, el objetiv...

  9. O significado do trabalho em funerárias sob a perspectiva do trabalhador

    OpenAIRE

    Kátia Cristina Caparroz de Souza; Magali Roseira Boemer

    1998-01-01

    A proposta do presente estudo foi buscar a essência do significado do trabalho em funerária, sob a perspectiva do trabalhador. Utilizando o referencial teórico-metodológico da fenomenologia foi possível, através da análise dos depoimentos dos trabalhadores, desvelar facetas que integram a essência do exercício de sua profissão. Os trabalhadores são conscientes do constrangimento e desconforto gerado pelo seu trabalho às pessoas de sua família e sociedade. Tal trabalho se mostra a eles como pr...

  10. Hacia una perspectiva contemporánea de lo sublime arquitectónico

    OpenAIRE

    Karina Contreras Castellanos

    2015-01-01

    Lo sublime parece ser un concepto diluido y ausente en la actualidad, pues ya no se presenta con la fuerza que lo hizo en otros momentos históricos. Este ensayo es parte de una investigación que presenta un recorrido a través de distintos momentos de la reflexión sobre lo sublime –y conceptos afines– como cualidad estética y como detonante de una gama de efectos, para conformar una perspectiva que permita ver en qué rango sigue presente como influencia en la estética y, sobre todo, en el ámbi...

  11. Die Aufzeichnungen des Malte Laurids Brigge: novas perspectivas de interpretação

    OpenAIRE

    Renata Martins

    2012-01-01

    O objetivo deste texto é analisar a experiência do estranho no romance Die Aufzeichnungen des Malte Laurids Brigge, de Rainer Maria Rilke, através de novas perspectivas de interpretação apoiadas, por exemplo, nas teorias psicanalíticas de Sigmund Freud. Vivendo em uma cidade estrangeira (Paris), com a qual ainda não se identifica, o protagonista do romance, Malte Laurids Brigge, descobre um mundo interior novo através de seu choque com experiências do estranho nesse milieu. A revelação de rec...

  12. Concepciones institucionalistas del lenguaje en la perspectiva pragmática contemporánea

    OpenAIRE

    Alegre, Javier

    2012-01-01

    La presente tesis versa sobre lo que hemos de denominar a lo largo de ella como concepción institucionalista del lenguaje, presente en distintas líneas del pragmatismo lingüístico contemporáneo. En una primera aproximación, ésta es sin dudas una investigación sobre el lenguaje, pero debido a que las perspectivas teóricas utilizadas entienden el lenguaje como institución y lo ponen en relación directa e inevitablemente con los procesos que se dan en las demás instituciones, en una inspección c...

  13. Violencia en la enseñanza obligatoria : alternativas desde la perspectiva del profesorado

    OpenAIRE

    Rodríguez Díaz, Francisco Javier; Gutiérrez Hernández, C.; Herrero Díez, Francisco Javier; Albuerne López, Ramón Fernando; Cuesta Izquierdo, Marcelino; Hernández Granda, Eva; Gómez Carbonero, Patricia; Jiménez Viñuela, María Asunción

    2004-01-01

    El objetivo de este artículo es establecer y conocer qué alternativas utiliza el profesorado para hacer frente a las situaciones de violencia escolar entre iguales, tanto aquellas que se producen en el aula como en el Centro, así como la oferta que se viene desarrollando desde su perspectiva a nivel de prevención. La muestra utilizada (n = 69 profesores de enseñanza obligatoria), tomada de diferentes Colegios de Enseñanza Primaria e IES de la Comunidad Autónoma del Principado de Asturias a tr...

  14. El papel de la madre en los trastornos de la conducta alimentaria: una perspectiva psicosocial

    OpenAIRE

    Vázquez Velázquez, Verónica; Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán; Reidl Martínez, Lucy María; Universidad Nacional Autónoma de México

    2013-01-01

    Se presenta una revisión de la literatura publicada acerca del papel de la madre en los trastornos de la conducta alimentaria desde una perspectiva psicosocial. Los trastornos de la conducta alimentaria, como la anorexia y bulimia nerviosas y el trastorno por atracón, son patologías psiquiátricas influidas por factores genéticos, psicológicos, sociales y ambientales. En el contexto familiar, resulta necesario precisar el papel que juega la madre en relación con el desarrollo y mantenimiento d...

  15. Bovinicultura tradicional no nordeste transmontano situação actual e perspectivas de desenvolvimento

    OpenAIRE

    Carvalho, Marieta

    1993-01-01

    Este trabalho pretende fazer uma prospecção tendente a averiguar o diagnóstico da situação actual do bovino Mirandês no quadro da estrutura agrária do Nordeste Transmontano, seu dinamismo e perspectivas de desenvolvimento. A área administrativa onde incide o presente estudo pertence à Região Agrária de Trás-os-Montes, situa-se na sub-região do Nordeste designada por Zona Agrária da Terra Fria que compreende o distrito de Bragança e Vinhais. A metodologia utilizada foi a investi...

  16. Suporte familiar ao idoso com comprometimento da funcionalidade: a perspectiva da família

    OpenAIRE

    Luciana Araújo dos Reis; Leny Alves Bonfim Trad

    2015-01-01

    Este estudio tiene como objetivo caracterizar el apoyo familiar a adultos mayores con deterioro de la capacidad funcional según los estratos socioeconómicos, desde la perspectiva del cuidador. El estudio fue realizado en cuatro unidades de salud en Jequié-BA. Los datos fueron recolectados a través de entrevista semi-estructurada y un cuestionario con las familias. A través de análisis de contenido emergieron las si-guientes categorías: significado de la capacidad funcional deteriorada; relaci...

  17. Perspectivas de la energía solar fotovoltaica en la edificación

    OpenAIRE

    González Brañas, Iván

    2015-01-01

    El presente proyecto tiene la finalidad de elaborar las perspectivas de futuro de la energía solar fotovoltaica, especialmente en España. Para ello se analiza en profundidad la tecnología fotovoltaica y su industria a nivel mundial para conocer en qué punto de desarrollo se encuentra. También se detalla la evolución del mercado fotovoltaico a nivel mundial, realzando los factores más importantes que lo han hecho posible. Para ir aproximándose al mercado fotovoltaico en España, se estudia más ...

  18. El text audiovisual: anàlisi des d'una perspectiva mediològica

    OpenAIRE

    Tous, Anna

    2008-01-01

    Consultable des del TDX Títol obtingut de la portada digitalitzada El text audiovisual: anàlisi des d'una perspectiva mediològica és una investigació sobre cinc sèries estatunidenques: El ala oeste de la Casa Blanca (The West Wing, NBC: 1999-2006), Perdidos (Lost, ABC: 2004-), Mujeres desesperadas (Desperate Housewives, ABC: 2004-), House (House, Fox: 2004-) i CSI: Las Vegas (CSI: Crime Scene Investigation, CBS: 2000-). De cadascuna de les sèries del corpus se n'analitza la primera temp...

  19. SALUD MENTAL: UN ABORDAJE DESDE LA PERSPECTIVA ACTUAL DE LA PSICOLOGÍA DE LA SALUD

    OpenAIRE

    Moisés Mebarak; Alberto De Castro; María del Pilar Salamanca; María Fernanda Quintero

    2009-01-01

    Este artículo está basado en un estudio estado del arte acerca del entendimiento actual que se tiene sobre el concepto de salud mental, especialmente desde la perspectiva de la psicología de la salud. Con el fin de ilustrar este campo, se presentan algunos aportes y/o investigaciones tanto a nivel general como de la región costa Caribe colombiana. Se ha encontrado que el concepto de salud mental implica el desarrollo de estilos de vida y de características personales, interpersonales, sociale...

  20. Evolución reciente y perspectivas del empleo en el Istmo Centroamericano

    OpenAIRE

    GUERRERO DE LIZARDI, CARLOS

    2007-01-01

    En el presente documento se analizan la evolución reciente y las perspectivas del mercado laboral en el Istmo Centroamericano. El examen histórico abarca el período desde la implantación del nuevo modelo de desarrollo en la región, básicamente a fines de los años ochenta y principios del decenio de 1990, hasta el año 2004, y el estudio prospectivo cubre hasta el año 2010. Durante las últimas décadas se observa un cuantioso desequilibrio en los mercados de trabajo q...

  1. El desarrollo humano: perfiles y perspectivas futuras /Profiles and Prospects of the Human Development

    OpenAIRE

    Torres Solé, Teresa; ALLEPUZ CAPDEVILA, RAFAEL

    2009-01-01

    El PNUD calcula todos los años el Índice de Desarrollo Humano (IDH). El objetivo de este trabajo es analizar los antecedentes y las perspectivas futuras del desarrollo humano a partir de los datos de este índice durante el periodo 1970-2000. Esto es, comprobar, a partir de los datos pasados, si las diferencias entre el IDH de los países del mundo están aumentando y valorar la tendencia del IDH esperada para los próximos años. En definitiva, se trata de buscar respuesta a la siguiente pregunta...

  2. Efecto de un programa educativo para cuidadores de personas ancianas: una perspectiva cultural

    OpenAIRE

    2012-01-01

    Objetivo Determinar el efecto de la aplicación de un programa educativo con perspectiva cultural para cuidadores de personas ancianas en situación de discapacidad y pobreza en un sector de Bogotá - Colombia, sobre las variables: auto percepción de salud, funcionalidad familiar, carga del cuidador y depresión. Métodos Estudio cuasiexperimental con pre-prueba y pos-prueba. Participaron 56 cuidadores familiares, 37 en el grupo experimental (ge) y 19 en el grupo control (gc).El programa educativo...

  3. Relevancia y conocimiento de las matemáticas: una perspectiva de estudiantes.

    OpenAIRE

    José Callejón Céspedes; Manuel Franco Nicolás; Juana María Vivo Molina

    2004-01-01

    El fracaso académico es un problema que, a lo largo de la historia, ha preocupado a profesores y que ha trascendido a los responsables políticos, economistas y en general a la sociedad. Han sido diversos los enfoques y numerosas las perspectivas (de los estudiantes, padres, docentes, políticos, …) desde las que se ha abordado esta situación, con la intención de paliar el fracaso académico; entre estos puntos de vista, en la actualidad, la valoración que hacen los propios estudiantes constituy...

  4. Gestion de indicadores en proyectos de software. Perspectivas actuales y futuras

    OpenAIRE

    Ramsés Delgado Martínez; Ana María García Pérez; José Alejandro Lugo García

    2011-01-01

    Se abordan las temáticas sobre la obtención de medidas e indicadores, así como modelos y herramientas surgidas a lo largo de las últimas décadas en torno a la medición de los procesos y construcción de productos de software, perspectivas actuales y futuras. El contenido servirá de apoyo para la conformación y despliegue del proceso de Medición y Análisis en el marco del Programa de Mejoras que lleva a cabo la Universidad de las Ciencias Informáticas (UCI).

  5. La perspectiva ecológica en el trabajo social con infancia, adolescencia y familia

    OpenAIRE

    Villalba Quesada, Cristina

    2004-01-01

    Para esta comunicación específica que propongo al Congreso Estatal de Escuelas de Trabajo Social, voy a plantear lo que, desde mi punto de vista, constituyen las ideas claves y las estrategias derivadas para la práctica de la Perspectiva Ecológica en Trabajo Social con Infancia, Adolescencia y Familia. Desde este posicionamiento se expondrán las diferencias entre los enfoques de riesgo, protección y resiliencia y se profundizará en las implicaciones teóricas, filosóficas y prácticas de las es...

  6. El cáncer de mama: desde la perspectiva de la experiencia

    OpenAIRE

    Nieto Flaño, Rebeca

    2013-01-01

    La presente monografía trata el cáncer de mama desde la perspectiva de la experiencia. Está estructurada en cinco capítulos en función de los siguientes objetivos: describir la vivencia de las mujeres con cáncer de mama, explicar el impacto del diagnóstico en la familia, analizar el impacto de la nueva imagen corporal, explicar los beneficios de la participación en grupos de apoyo, y la importancia del uso de la metodología enfermera en el cuidado de estas pacientes. Las neoplasias de mama so...

  7. Diseño conceptual del emprendimiento para el desarrollo regional en la perspectiva de la complejidad autopoiesica

    OpenAIRE

    Porras Jiménez, Jaime Augusto

    2006-01-01

    El Diseño Conceptual del Emprendimiento para el Desarrollo Regional en la perspectiva de la Complejidad Autopoiésica, además de la primera parte sobre el diseño metodológico aplicado en el proceso investigativo, comprende dos partes, el estudio del “estado del emprendimiento y su contexto” con énfasis en la génesis conceptual del Emprendimiento y, el estudio sobre la “conceptualización del emprendimiento” con énfasis propositivo desde una perspectiva epistemológica y reflexiva. En el estado d...

  8. Caracterización de las mujeres maltratadas por su pareja desde la perspectiva de género

    OpenAIRE

    Marioly Ruiz Hernández; Laura López Angulo; Yoan Hernández Cabrera; Eduardo Castañeda Álvarez; Yisel Águila Rodríguez

    2013-01-01

    Fundamento: el estudio de la violencia desde la perspectiva de género aporta una nueva lectura en el comportamiento de las mujeres que rompen o no con relaciones abusivas. Objetivo: caracterizar desde la perspectiva de género a las mujeres que han sido maltratadas por su pareja. Métodos: estudio descriptivo, realizado en el policlínico Área V del municipio Cienfuegos en el año 2010. Fueron estudiadas 21 mujeres que denunciaron el delito y 42 maltratadas que no lo denunciaron, pertenecientes a...

  9. El valor de marca: perspectivas de análisis y criterios de estimación

    OpenAIRE

    Del Río Lanza, Ana Belén; Vázquez Casielles, Rodolfo; Iglesias Argüelles, Víctor

    2002-01-01

    [ES] A lo largo de la última década, se ha originado un importante debate acerca de lo que debe entenderse por valor de marca. En la delimitación de este concepto se han utilizado varias perspectivas de análisis y criterios de estimación muy diferentes, de ahí que aún exista sobre este tema una excesiva ambigüedad. En este trabajo se presenta un marco teórico donde se contemplan distintas perspectivas de estudio y varios criterios de estimación del valor de marca. A partir de este marco, s...

  10. Revisión entre iguales y escritura académica en la universidad: la perspectiva del estudiante

    OpenAIRE

    Alfonso Vargas Franco

    2014-01-01

    Este artículo presenta los primeros resultados de una investigación que tuvo como objeto documentar los puntos de vista (representaciones, grado de conciencia, actitudes, opiniones) que tiene un grupo de estudiantes, desde una perspectiva émica (una perspectiva del informante, del estudiante, que también es autor del texto), sobre la escritura académica, sus roles de autor y lector y los procesos de revisión entre iguales, en una secuencia de aprendizaje de resúmenes, reseñas y artículos acad...

  11. Aportaciones de la perspectiva de género a la investigación epidemiológica

    OpenAIRE

    García Gil, Carmen; Álvarez Girón, Manuela; Solano Parés, Ana

    2009-01-01

    El Grupo de Investigación “Análisis epidemiológico de las desigualdades sociales ante la salud”, constituido en 1987, viene trabajando, desde sus inicios, en el desarrollo de metodologías de investigación que abran el campo de la salud a una perspectiva social y poblacional, más allá de lo biomédico. La perspectiva de género, introducida en los últimos años, ha sido el resultado que le ha dado coherencia a las distintas líneas de investigación emprendidas y nos ha abierto a la ...

  12. Condicionantes de la respuesta vegetal al cambio climático. Una perspectiva paleobiológica

    OpenAIRE

    Carrión García, José Sebastián

    2001-01-01

    Condicionantes de la respuesta vegetal al cambio climático. Una perspectiva paleobiológica. Este artículo proporciona una revisión de las pautas y procesos de cambio vegetal en relación con el cambio climático, así como sobre la cuestión del equilibrio clima-vegetación y sus condicionantes, desde una perspectiva paleobiológica basada fundamentalmente en secuencias polínicas. En la escala evolutiva, la mayor parte de los eventos de migración, extinción de especies y reorganización de la estruc...

  13. In pursuit of an accurate spatial and temporal model of biomolecules at the atomistic level: a perspective on computer simulation

    Energy Technology Data Exchange (ETDEWEB)

    Gray, Alan [The University of Edinburgh, Edinburgh EH9 3JZ, Scotland (United Kingdom); Harlen, Oliver G. [University of Leeds, Leeds LS2 9JT (United Kingdom); Harris, Sarah A., E-mail: s.a.harris@leeds.ac.uk [University of Leeds, Leeds LS2 9JT (United Kingdom); University of Leeds, Leeds LS2 9JT (United Kingdom); Khalid, Syma; Leung, Yuk Ming [University of Southampton, Southampton SO17 1BJ (United Kingdom); Lonsdale, Richard [Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr (Germany); Philipps-Universität Marburg, Hans-Meerwein Strasse, 35032 Marburg (Germany); Mulholland, Adrian J. [University of Bristol, Bristol BS8 1TS (United Kingdom); Pearson, Arwen R. [University of Leeds, Leeds LS2 9JT (United Kingdom); University of Hamburg, Hamburg (Germany); Read, Daniel J.; Richardson, Robin A. [University of Leeds, Leeds LS2 9JT (United Kingdom); The University of Edinburgh, Edinburgh EH9 3JZ, Scotland (United Kingdom)

    2015-01-01

    The current computational techniques available for biomolecular simulation are described, and the successes and limitations of each with reference to the experimental biophysical methods that they complement are presented. Despite huge advances in the computational techniques available for simulating biomolecules at the quantum-mechanical, atomistic and coarse-grained levels, there is still a widespread perception amongst the experimental community that these calculations are highly specialist and are not generally applicable by researchers outside the theoretical community. In this article, the successes and limitations of biomolecular simulation and the further developments that are likely in the near future are discussed. A brief overview is also provided of the experimental biophysical methods that are commonly used to probe biomolecular structure and dynamics, and the accuracy of the information that can be obtained from each is compared with that from modelling. It is concluded that progress towards an accurate spatial and temporal model of biomacromolecules requires a combination of all of these biophysical techniques, both experimental and computational.

  14. New Dioxaborolane Chemistry Enables [(18)F]-Positron-Emitting, Fluorescent [(18)F]-Multimodality Biomolecule Generation from the Solid Phase.

    Science.gov (United States)

    Rodriguez, Erik A; Wang, Ye; Crisp, Jessica L; Vera, David R; Tsien, Roger Y; Ting, Richard

    2016-05-18

    New protecting group chemistry is used to greatly simplify imaging probe production. Temperature and organic solvent-sensitive biomolecules are covalently attached to a biotin-bearing dioxaborolane, which facilitates antibody immobilization on a streptavidin-agarose solid-phase support. Treatment with aqueous fluoride triggers fluoride-labeled antibody release from the solid phase, separated from unlabeled antibody, and creates [(18)F]-trifluoroborate-antibody for positron emission tomography and near-infrared fluorescent (PET/NIRF) multimodality imaging. This dioxaborolane-fluoride reaction is bioorthogonal, does not inhibit antigen binding, and increases [(18)F]-specific activity relative to solution-based radiosyntheses. Two applications are investigated: an anti-epithelial cell adhesion molecule (EpCAM) monoclonal antibody (mAb) that labels prostate tumors and Cetuximab, an anti-epidermal growth factor receptor (EGFR) mAb (FDA approved) that labels lung adenocarcinoma tumors. Colocalized, tumor-specific NIRF and PET imaging confirm utility of the new technology. The described chemistry should allow labeling of many commercial systems, diabodies, nanoparticles, and small molecules for dual modality imaging of many diseases. PMID:27064381

  15. Direct Biomolecules Binding on Nonfouling Surface via Newly Discovered Supramolecular Self-assembly of Lysozyme under Physiological Condition

    Science.gov (United States)

    Yang, Peng

    2013-01-01

    A major challenge in the development of low cost and practical strategies for biomolecules immobilization on solid supports is that the multi-step chemical/physical activating and following deactivating procedures on nonfouling substrates often increase the cost and complexity of surface functional group types as well as deteriorate the surface integrity. Herein, we show a novel phase transition of lysozyme could be used to constitute a major step to address the above problem. It is found that when lysozyme is dissolved in a neutral buffer solution of 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES, pH 7.4) with 1–50 mM tris(2-carboxyethyl)phosphine (TCEP) added, a fast phase transition process occurs and the resulting novel fibra-like hierarchical supramolecular assemblies made by primary spherical particles aggregation would function as a “superglue” that strongly and quickly bind onto non-fouling coatings. This binding is highly selective towards lysozyme, and excludes completely tedious synthetical, chemical/physical activation/deactivation (blocking) steps. When biotin is conjugated with lysozyme, such phase transition quickly constructs a perfect biotinylated surface on nonfouling surface for avidin binding, showing great potential for the development of low-cost and practical biochips. PMID:22707360

  16. Plant-mediated synthesis of highly active iron nanoparticles for Cr (VI) removal: Investigation of the leading biomolecules.

    Science.gov (United States)

    Xiao, Zhengli; Yuan, Min; Yang, Bin; Liu, Zhaoyan; Huang, Jiale; Sun, Daohua

    2016-05-01

    The eco-friendly synthesis and application of Fe nanoparticles (Fe NPs) with higher activity and stability has aroused wide attention in the field of pollutant remediation. In this work, 15 plants extracts were selected for the plant-mediated synthesis of Fe NPs. The as-synthesized particles' morphology and structure were characterized by transmission electron microscopy, X-ray diffraction and UV-Vis spectroscopy. The contents of four main active biomolecules in the 15 extracts were determined, and comparative studies were further carried out to clarify the key component closely related to the reducing capacity. The results demonstrate that polyphenol is the leading ingredient involved in the biosynthesis of Fe NPs. Then Fe products synthesized by three extracts with distinct content of polyphenol were employed to remove Cr (VI) in the aqueous solution, indicating that the activity of the Fe NPs for Cr (VI) removal is consistent with the reducing capacity of the extracts. Furthermore, the Fe NPs synthesized by S. jambos(L.) Alston extract (SJA-Fe NPs) showed significant removal capacity of Cr(VI) with 698.6 mg Cr(VI) per g of iron. PMID:26921588

  17. A novel promising biomolecule immobilization matrix: synthesis of functional benzimidazole containing conducting polymer and its biosensor applications.

    Science.gov (United States)

    Uzun, Sema Demirci; Unlu, Naime Akbasoglu; Sendur, Merve; Kanik, Fulya Ekiz; Timur, Suna; Toppare, Levent

    2013-12-01

    In order to construct a robust covalent binding between biomolecule and immobilization platform in biosensor preparation, a novel functional monomer 4-(4,7-di(thiophen-2-yl)-1H-benzo[d]imidazol-2-yl)benzaldehyde (BIBA) was designed and successfully synthesized. After electropolymerization of this monomer, electrochemical and spectroelectrochemical properties were investigated in detail. To fabricate the desired biosensor, glucose oxidase (GOx) was immobilized as a model enzyme on the polymer coated graphite electrode with the help of glutaraldehyde (GA). During the immobilization step, an imine bond was formed between the free amino groups of enzyme and aldehyde group of polymer. The surface characterization and morphology were investigated to confirm bioconjugation by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) at each step of biosensor fabrication. The optimized biosensor shows good linearity between 0.02mM and 1.20mM and a low limit of detection (LOD) of 2.29μM. Kinetic parameters Km(app) and Imax were determined as 0.94mM and 10.91μA, respectively. The biosensor was tested for human blood serum samples. PMID:23973906

  18. Computer simulations of plasma–biomolecule and plasma–tissue interactions for a better insight in plasma medicine

    International Nuclear Information System (INIS)

    Plasma medicine is a rapidly evolving multidisciplinary field at the intersection of chemistry, biochemistry, physics, biology, medicine and bioengineering. It holds great potential in medical, health care, dentistry, surgical, food treatment and other applications. This multidisciplinary nature and variety of possible applications come along with an inherent and intrinsic complexity. Advancing plasma medicine to the stage that it becomes an everyday tool in its respective fields requires a fundamental understanding of the basic processes, which is lacking so far. However, some major advances have already been made through detailed experiments over the last 15 years. Complementary, computer simulations may provide insight that is difficult—if not impossible—to obtain through experiments. In this review, we aim to provide an overview of the various simulations that have been carried out in the context of plasma medicine so far, or that are relevant for plasma medicine. We focus our attention mostly on atomistic simulations dealing with plasma–biomolecule interactions. We also provide a perspective and tentative list of opportunities for future modelling studies that are likely to further advance the field. (topical review)

  19. Polystyrene nanoparticles facilitate the internalization of impermeable biomolecules in non-tumour and tumour cells from colon epithelium

    International Nuclear Information System (INIS)

    Advanced colon cancer has a poor prognosis due to the limited effectiveness of current chemotherapies. Treatment failures may be avoided by the utilization of nanoparticles, which can enhance the effects of antitumor drugs, reduce their side effects and increase their directionality. Polystyrene nanoparticles have shown high biocompatibility and appropriate physicochemical properties and may represent a novel and more effective approach against colon cancer. In the present study, polystyrene nanoparticles were synthesized and fluorescently labelled, analyzing their cell internalization, intracellular localization and capacity to release transported molecules in tumour and non-tumour human colon cell lines (T84 and CCD-18). Flow cytometry and fluorescence microscopy studies demonstrated that polystyrene nanoparticles are an effective vehicle for the intracellular delivery of small molecules into colon epithelium cells. The percentage cell uptake was around 100 % in both T84 and CCD-18 cell lines after only 24 h of exposure and was cell confluence-independent. The polystyrene nanoparticles showed no cytotoxicity in either colon cell line. It was found that small molecules can be efficiently delivered into colon cells by using a disulphide bridge as release strategy. Analysis of the influence of the functionalization of the polystyrene nanoparticles surface on the internalization efficiency revealed some morphological changes in these cells. These results demonstrate that polystyrene nanoparticles may improve the transport of biomolecules into colon cells which could have a potential application in chemotherapeutic treatment against colon cancer

  20. Boronate Affinity Fluorescent Nanoparticles for Förster Resonance Energy Transfer Inhibition Assay of cis-Diol Biomolecules.

    Science.gov (United States)

    Wang, Shuangshou; Ye, Jin; Li, Xinglin; Liu, Zhen

    2016-05-17

    Förster resonance energy transfer (FRET) has been essential for many applications, in which an appropriate donor-acceptor pair is the key. Traditional dye-to-dye combinations remain the working horses but are rather nonspecifically susceptive to environmental factors (such as ionic strength, pH, oxygen, etc.). Besides, to obtain desired selectivity, functionalization of the donor or acceptor is essential but usually tedious. Herein, we present fluorescent poly(m-aminophenylboronic acid) nanoparticles (poly(mAPBA) NPs) synthesized via a simple procedure and demonstrate a FRET scheme with suppressed environmental effects for the selective sensing of cis-diol biomolecules. The NPs exhibited stable fluorescence properties, resistance to environmental factors, and a Förster distance comparable size, making them ideal donor for FRET applications. By using poly(mAPBA) NPs and adenosine 5'-monophosphate modified graphene oxide (AMP-GO) as a donor and an acceptor, respectively, an environmental effects-suppressed boronate affinity-mediated FRET system was established. The fluorescence of poly(mAPBA) NPs was quenched by AMP-GO while it was restored when a competing cis-diol compounds was present. The FRET system exhibited excellent selectivity and improved sensitivity toward cis-diol compounds. Quantitative inhibition assay of glucose in human serum was demonstrated. As many cis-diol compounds such as sugars and glycoproteins are biologically and clinically significant, the FRET scheme presented herein could find more promising applications. PMID:27089186

  1. Computer simulations of plasma-biomolecule and plasma-tissue interactions for a better insight in plasma medicine

    Science.gov (United States)

    Neyts, Erik C.; Yusupov, Maksudbek; Verlackt, Christof C.; Bogaerts, Annemie

    2014-07-01

    Plasma medicine is a rapidly evolving multidisciplinary field at the intersection of chemistry, biochemistry, physics, biology, medicine and bioengineering. It holds great potential in medical, health care, dentistry, surgical, food treatment and other applications. This multidisciplinary nature and variety of possible applications come along with an inherent and intrinsic complexity. Advancing plasma medicine to the stage that it becomes an everyday tool in its respective fields requires a fundamental understanding of the basic processes, which is lacking so far. However, some major advances have already been made through detailed experiments over the last 15 years. Complementary, computer simulations may provide insight that is difficult—if not impossible—to obtain through experiments. In this review, we aim to provide an overview of the various simulations that have been carried out in the context of plasma medicine so far, or that are relevant for plasma medicine. We focus our attention mostly on atomistic simulations dealing with plasma-biomolecule interactions. We also provide a perspective and tentative list of opportunities for future modelling studies that are likely to further advance the field.

  2. Photostability of gas- and solid-phase biomolecules within dense molecular clouds due to soft X-rays

    CERN Document Server

    Pilling, S; Nascimento, E M do; Marinho, R R T; Boechat-Roberty, H M; de Coutinho, L H; de Souza, G G B; de Castilho, R B; Cavasso-Filho, R L; Lago, A F; de Brito, A N

    2010-01-01

    An experimental photochemistry study involving gas- and solid-phase amino acids (glycine, DL-valine, DL-proline) and nucleobases (adenine and uracil) under soft X-rays was performed. The aim was to test the molecular stabilities of essential biomolecules against ionizing photon fields inside dense molecular clouds and protostellar disks analogs. In these environments, the main energy sources are the cosmic rays and soft X-rays. The measurements were taken at the Brazilian Synchrotron Light Laboratory (LNLS), employing 150 eV photons. In-situ sample analysis was performed by Time-of-flight mass spectrometer (TOF-MS) and Fourier transform infrared (FTIR) spectrometer, for gas- and solid- phase analysis, respectively. The half-life of solid phase amino acids, assumed to be present at grain mantles, is at least 3E5 years and 3E8 years inside dense molecular clouds and protoplanetary disks, respectively. We estimate that for gas-phase compounds these values increase one order of magnitude since the dissociation cr...

  3. Polystyrene nanoparticles facilitate the internalization of impermeable biomolecules in non-tumour and tumour cells from colon epithelium

    Energy Technology Data Exchange (ETDEWEB)

    Cabeza, Laura [University of Granada, Department of Human Anatomy and Embryology, Institute of Biopathology and Regenerative Medicine (IBIMER) (Spain); Cano-Cortés, Victoria; Rodríguez, María J. [University of Granada, Department of Pharmaceutical and Organic Chemistry (Spain); Vélez, Celia; Melguizo, Consolación, E-mail: melguizo@ugr.es [University of Granada, Department of Human Anatomy and Embryology, Institute of Biopathology and Regenerative Medicine (IBIMER) (Spain); Sánchez-Martín, Rosario M., E-mail: rmsanchez@ugr.es [University of Granada, Department of Pharmaceutical and Organic Chemistry (Spain); Prados, Jose [University of Granada, Department of Human Anatomy and Embryology, Institute of Biopathology and Regenerative Medicine (IBIMER) (Spain)

    2015-01-15

    Advanced colon cancer has a poor prognosis due to the limited effectiveness of current chemotherapies. Treatment failures may be avoided by the utilization of nanoparticles, which can enhance the effects of antitumor drugs, reduce their side effects and increase their directionality. Polystyrene nanoparticles have shown high biocompatibility and appropriate physicochemical properties and may represent a novel and more effective approach against colon cancer. In the present study, polystyrene nanoparticles were synthesized and fluorescently labelled, analyzing their cell internalization, intracellular localization and capacity to release transported molecules in tumour and non-tumour human colon cell lines (T84 and CCD-18). Flow cytometry and fluorescence microscopy studies demonstrated that polystyrene nanoparticles are an effective vehicle for the intracellular delivery of small molecules into colon epithelium cells. The percentage cell uptake was around 100 % in both T84 and CCD-18 cell lines after only 24 h of exposure and was cell confluence-independent. The polystyrene nanoparticles showed no cytotoxicity in either colon cell line. It was found that small molecules can be efficiently delivered into colon cells by using a disulphide bridge as release strategy. Analysis of the influence of the functionalization of the polystyrene nanoparticles surface on the internalization efficiency revealed some morphological changes in these cells. These results demonstrate that polystyrene nanoparticles may improve the transport of biomolecules into colon cells which could have a potential application in chemotherapeutic treatment against colon cancer.

  4. Overview of the use of theory to understand infrared and Raman spectra and images of biomolecules: colorectal cancer as an example

    DEFF Research Database (Denmark)

    Piva, J. A. A. C.; Silva, J. L. R.; Raniero, L.;

    2011-01-01

    In this work, we present the state of the art in the use of theory (first principles, molecular dynamics, and statistical methods) for interpreting and understanding the infrared (vibrational) absorption and Raman scattering spectra. It is discussed how they can be used in combination with purely...... experimental studies to generate infrared and Raman images of biomolecules in biologically relevant solutions, including fluids, cells, and both healthy and diseased tissue. The species and conformers of the individual biomolecules are in many cases not stable structures, species, or conformers in the isolated...... state or in non-polar non-strongly interacting solvents. Hence, it is better to think of the collective behavior of the system. The collective interaction is not the simple sum of the individual parts. Here, we will show that this is also not true for the infrared and Raman spectra and images and that...

  5. Cu(I), Ag(I), Cd(II), and Pb(II) binding to biomolecules studied by perturbed angular correlation of $\\gamma$-rays (PAC) spectroscopy

    CERN Multimedia

    Metal ions display diverse functions in biological systems and are essential components in both protein and nucleic acid structure and function, and in control of biochemical reaction paths and signalling. Similarly, metal ions may be used to control structure and function of synthetic biomolecules, and thus be a tool in the design of molecules with a desired function. In this project we address a variety of questions concerning both the function of metal ions in natural systems, in synthetic biomolecules, and the toxic effect of some metal ions. All projects involve other experimental techniques such as NMR, EXAFS, UV-Vis, fluorescence, and CD spectroscopies providing complementary data, as well as interpretation of the experimental data by quantum mechanical calculations of spectroscopic properties. The isotopes to be employed in the proposal are the following: $^{111m}$Cd, $^{111}$Ag, $^{199}$mHg, $^{204m}$Pb, $^{61}$Cu, $^{68m}$Cu

  6. Antioxidant, Biomolecule Oxidation Protective Activities of Nardostachys jatamansi DC and Its Phytochemical Analysis by RP-HPLC and GC-MS

    OpenAIRE

    Sakina Razack; Kandikattu Hemanth Kumar; Ilaiyaraja Nallamuthu; Mahadeva Naika; Farhath Khanum

    2015-01-01

    The study aimed at analyzing the metabolite profile of Nardostachys jatamansi using RP-HPLC, GC-MS and also its antioxidant, biomolecule protective and cytoprotective properties. The 70% ethanolic extract of Nardostachys jatamansi (NJE) showed the presence of polyphenols and flavonoids (gallic acid, catechin, chlorogenic acid, homovanillin, epicatechin, rutin hydrate and quercetin-3-rhamnoside) analyzed by RP-HPLC, whereas hexane extract revealed an array of metabolites (fatty acids, sesquite...

  7. Etymology of transition metal biomolecules as a learning aid in Biological Chemistry; A etimologia de biomoleculas com metais de transicao como auxiliar na aprendizagem de Quimica Biologica

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Jose A.L. da, E-mail: pcd1950@ist.utl.pt [Universidade Tecnica de Lisboa (Portugal). Instituto Superior Tecnico. Centro de Quimico Estrutural

    2013-11-01

    Numerous functional biomolecules are associated with metals, i.e. the metallobiomolecules; more specifically, some are dependent on transition metals required for several crucial biological roles. Nevertheless, their names can lead to ambiguous interpretations concerning the properties and performances of this group of biological molecules. Their etymology may be useful by providing a more perceptive insight into their features. However, etymology can lead to incongruous conclusions, requiring an especially careful approach to prevent errors. Examples illustrating these subjects shall be examined (author)

  8. Computational modeling of the enzymatic activities of biomolecules at different scales: from quantum mechanical reaction studies to systemic understanding of cell behavior

    OpenAIRE

    Barbieri,, R.

    2012-01-01

    The aim of the thesis is the development of computational models of the enzymatic activity of biomolecules at different scales. Parallel investigations have been carried out at a quantum level to study the reactivity of an enzyme from an electronic point of view, and at a systemic level using simulation techniques to determine the role of enzymes in the network of cellular reactions. Starting from the lowest complexity level, the thesis begins with two computational studies with the aims ...

  9. Preventive effect of glycosaminoglycans from Amussium pleuronectus (Linne) on biomolecules, lactate dehydrogenase-isoenzyme and electrocardiographic patterns in isoproterenol-induced myocardial infarction in Wistar rats

    OpenAIRE

    Ramachandran Saravanan; Annaian Shanmugam; Devaraj Rajkumar

    2012-01-01

    Objectives: This study was aimed to assess the cardioprotective role of low molecular weight glycosaminoglycans (LMW-GAG) in isoproterenol (ISO)-induced myocardial infarction (MI) in male Wistar rats. Effect of LMW-GAG on biomolecules, lactate dehydrogenase (LDH)-isoenzyme, and electrocardiographic (ECG)-patterns was studied as evidence of cardioprotection. Materials and Methods: Male Wistar rats (140 ± 10 g) were divided into four groups; untreated control (group I), LMW-GAG treated (300 ...

  10. Biomass-derived functional porous carbons as novel electrode material for the practical detection of biomolecules in human serum and snail hemolymph

    Science.gov (United States)

    Veeramani, Vediyappan; Madhu, Rajesh; Chen, Shen-Ming; Lou, Bih-Show; Palanisamy, Jayabal; Vasantha, Vairathevar Sivasamy

    2015-05-01

    The biomass-derived activated carbons (ACs) have been prepared with high surface areas up to 793 m2 g-1 is by ZnCl2 activation at three different temperatures, viz. AC700, AC800, and AC900. The AC samples were characterized by a variety of analytical and spectroscopy techniques. The as-synthesized ACs were adopted for the simultaneous electrochemical detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA). For comparison, reduced graphene oxide (RGO) was employed for the proposed sensor. The high surface area, modulated pore size and the presence of oxygen surface functional groups like heteroatoms (83.427% C, 1.085% N, 0.383% S, and 0.861% H) in the biomass-derived AC is found to be responsible for the excellent catalytic activities of biomolecules. Fascinatingly, the facile sensor further used to detect biomolecules levels in the snail hemolymph and human blood serum. Notably, the obtained analytical parameters for the biomolecules detection over the AC modified GCE, outperforming several carbon-based modified electrodes in literatures.

  11. Characterization of bimetallic Fe/Pd nanoparticles by grape leaf aqueous extract and identification of active biomolecules involved in the synthesis.

    Science.gov (United States)

    Luo, Fang; Yang, Die; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravi

    2016-08-15

    This paper reports the detailed composition and morphology of one-step green synthesized bimetallic Fe/Pd nanoparticles (NPs) using grape leaf aqueous extract and identification of active biomolecules involved in the synthesis employing various techniques. Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) revealed that Fe/Pd NPs were polydispersed and quasi-spherical with a diameter ranging from 2 to 20nm. X-ray Photoelectron Spectroscopy (XPS) and Energy Dispersive X-ray Spectroscopy (EDS) provided evidence for the composition of Fe and Pd and for their species existing on the surface of Fe/Pd NPs. In addition, biomolecules in the grape leaf aqueous extract were identified but their functions are still unclear. Biomolecules in the aqueous extract such as methoxy-phenyl-oxime, N-benzoyl-2-cyano-histamine, 2-ethyl-phenol, 1,2-benzenediol, β-hydroxyquebracamine, hydroquinone, 2-methoxy-4-vinylphenol, 5-methyl-2-furancarboxaldehyde, 4-(3-hydroxybutyl)-3,5,5-trimethyl-2-cyclohexen and some polyphenolic compounds were identified as reducing and capping agents, which were studied by Chromatography-Mass Spectroscopy (GC-MS), XPS and Fourier Transform Infrared Spectroscopy (FTIR). Our finding suggests a new insight into cost-effective, simple, and environmentally benign production of bimetallic Fe/Pd NPs. PMID:27110966

  12. Abordando la problemática del Dengue desde una perspectiva ambiental

    Directory of Open Access Journals (Sweden)

    Claudia Zuñiga Vega

    2009-01-01

    Full Text Available El Dengue es una enfermedad viral que genera danos cuantiosos en los países donde se desarrolla, afectando la economía, las actividades productivas y el turismo, entre otros. El principal transmisor de esta enfermedad es el mosquito Aedes aegypti y las campanas para erradicar este vector se han dirigido principalmente hacia la eliminación de sus larvas y adultos por medio de plaguicidas y hacia la reducción del mal manejo de los desechos. Sin embargo, no se ha realizado esfuerzos para determinar las razones por las que las poblaciones de este mosquito han sido tan exitosas, ni se ha aplicado enfoques integrales para luchar contra esta pandemia. Este artículo trata de explicar el incremento de los casos de Dengue desde la perspectiva del descontrol y desinterés ambiental y la falta de apoyo a las comunidades en muchos campos. Es por esto que los autores proponen abordar esta problemática desde una perspectiva ambiental integral, abarcando desde el control químico y biológico hasta la integración de todos los sectores involucrados (Gobierno, médicos y comunidad.

  13. Perspectivas das pesquisas em gerontologia e geriatria: revisão da literatura

    Directory of Open Access Journals (Sweden)

    Freitas Maria Célia de

    2002-01-01

    Full Text Available Este estudo é exploratório e descritivo e objetivou identificar e analisar as tendências e perspectivas das pesquisas nas áreas de gerontologia e geriatria. Realizou-se levantamento bibliográfico, junto ao Banco de Dados Lilacs e acervo da Escola de Enfermagem de Ribeirão Preto-USP, de publicações multiprofissionais, no período de 1980 a 2000. Apresentaram-se os resultados sob a forma de tabelas e gráficos, destacando-se os estudos com enfoque geriátrico (54%. Quanto às abordagens, houve, na última década (1990 a 2000, aumento, distribuindo-se em Biológica (32%, Recursos Humanos (18%, Social (17%, Psicológica (9,8%, Holística (4,0%, excetuando-se a Ética que permaneceu com o mesmo percentual nos dois períodos (0,8%. Em relação ao tipo de pesquisa, predominou a qualitativa (49,2%. Verifica-se, portanto, que as perspectivas em relação aos idosos indicaram interesse dos profissionais pela temática, tanto pelas transições demográficas e epidemiológicas quanto pela formação de recursos humanos, para o mundo do trabalho junto a idosos, no âmbito profissional e no domiciliar.

  14. Medición y determinantes del valor de marca en la perspectiva del consumidor

    Directory of Open Access Journals (Sweden)

    Martin de La Martinière Petroll

    2008-12-01

    Full Text Available Varios autores (Aaker 1992 y 1998, Keller 1993, Ogrizek 2002, Hoeffler y Keller 2002 afirman que existen muchas ventajas para que una empresa tenga una marca fuerte, pues brinda una importante ventaja competitiva, al establecer una barrera que evita que los consumidores cambien de marca (Aaker 1992. Por este motivo, la medición del valor de marca y la identificación de los elementos esenciales de su gestión pasan a ser considerados puntos fundamentales en el área de marketing. Hace una década, el Marketing Science Institute coloca ese tema como la prioridad máxima en sus indicaciones de tópicos de investigación (Ailawadi et al. 2003. A pesar de la extensa literatura sobre el valor de marca, se observa una divergencia acerca de su concepto, de las dimensiones que definen ese constructo, de los factores que la influencian, de las perspectivas por las cuales la misma debería ser estudiada y de las formas de medición. Esta es la base de sustentación de este trabajo, que tuvo como objetivo examinar la literatura más relevante sobre valor de marca para analizar los conceptos utilizados sobre marca y valor de marca, las dimensiones de ese constructo y las perspectivas de medición.  

  15. GOBERNABILIDAD: UNA APROXIMACIÓN CONCEPTUAL DESDE LA PERSPECTIVA DE LA GUBERNAMENTALIDAD

    Directory of Open Access Journals (Sweden)

    Martín Carné

    2012-12-01

    Full Text Available El trabajo que tiene por objetivo analizar la pertinencia y las potencialidades que la perspectiva de la gubernamentalidad puede ofrecer a la categoría “gobernabilidad” más allá de los abordajes de corte institucionalista que predominan en la Ciencia Política de la región. Así como la gobernabilidad se derivaría de un ejercicio del poder político sometido a “reglas de juego” que regulan las acciones de los actores y confieren capacidades para atender demandas sociales, nos preguntamos, como hipótesis, si aquélla puede también pensarse como el resultado de racionalidades y tecnologías de gobierno de corte neoliberal tendientes a constituir sujetos gobernables. Basándonos en la lectura de documentos académicos – y reconociendo que el presente trabajo constituye una primera aproximación sobre la problematización planteada – concluimos que la perspectiva de la gubernamentalidad ofrece herramientas útiles para tratar la gobernabilidad de un orden político.

  16. LIDERAZGO Y RENDIMIENTO DE LA GERENCIA INTERMEDIA BAJO LA PERSPECTIVA DE LOS OBJETIVOS BALANCEADOS

    Directory of Open Access Journals (Sweden)

    Eleonora Parra de Párraga

    2006-07-01

    Full Text Available Analizar una empresa desde la perspectiva del liderazgo y el rendimiento utilizando como método los objetivos balanceados o Cuadro de Mando Integral, implica la utilización de herramientas poco comunes pero exitosas. Enfrentar una investigación desde varios ángulos presenta la oportunidad de observar con mayor detenimiento las diversas áreas que presentan problemas y determinar así la mejor forma de resolverlos. El método de los objetivos balanceados o Cuadro de Mando Integral, ofrece esta oportunidad, a cualquier organización. Dicho método puede emplearse desde la perspectiva tanto financiera como no financiera, lo básico es que le indica al empresario donde están sus fallas y cómo debe corregirlas. Lo primordial es lograr el éxito en todos los órdenes, y eso lo puede lograr al precisar un eficiente liderazgo decidido a mejorar u optimizar el rendimiento empresarial.

  17. Competitividade e Papel do Poder Público a Partir da Perspectiva Evolucionária

    Directory of Open Access Journals (Sweden)

    Andréia Aparecida Albino

    2010-12-01

    Full Text Available

    Este estudo explora conceitos da teoria econômica evolucionária, com o objetivo de propor uma perspectiva inovadora para se estudar aglomerações industriais ou Arranjos Produtivos Locais (APLs. Em consonância com a perspectiva evolucionária, insere-se o conceito de cadeia de valor, como estrutura analítica para analisar a dinâmica competitiva de APLs. Apresentam-se elementos que parecem apropriados ao estudo da cadeia produtiva moveleira, com base na estrutura proposta. A principal contribuição do trabalho consiste na proposta de uma estrutura analítica de simples aplicação e que permite classificar empresas de um APL, segundo seus padrões estratégicos e competitivos, bem como identificar características que merecem destaque e, até, atenção por parte de empresários e de formuladores de políticas públicas.

  18. Competitividade e Papel do Poder Público a Partir da Perspectiva Evolucionária

    Directory of Open Access Journals (Sweden)

    Andréia Aparecida Albino

    2010-12-01

    Full Text Available Este estudo explora conceitos da teoria econômica evolucionária, com o objetivo de propor uma perspectiva inovadora para se estudar aglomerações industriais ou Arranjos Produtivos Locais (APLs. Em consonância com a perspectiva evolucionária, insere-se o conceito de cadeia de valor, como estrutura analítica para analisar a dinâmica competitiva de APLs. Apresentam-se elementos que parecem apropriados ao estudo da cadeia produtiva moveleira, com base na estrutura proposta. A principal contribuição do trabalho consiste na proposta de uma estrutura analítica de simples aplicação e que permite classificar empresas de um APL, segundo seus padrões estratégicos e competitivos, bem como identificar características que merecem destaque e, até, atenção por parte de empresários e de formuladores de políticas públicas.

  19. PERSPECTIVAS ANALÍTICAS E PROGRAMAS DE PESQUISA SOBRE A COOPERAÇÃO SOCIAL

    Directory of Open Access Journals (Sweden)

    Silvio Segundo Salej Higgins

    2015-12-01

    Full Text Available Resumo:Este artigo examina formatos teóricos que rivalizam em sua forma de explicar a cooperação social. São expostas duas perspectivas teóricas distintas, através das pesquisas de Jean Piaget e de autores da Teoria da Escolha Racional. Enquanto a primeira compreende a cooperação a partir da evolução das estruturas cognitivas morais, a segunda vê-la como resultado da coordenação dos interesses de atores racionais. Após a exposição de recentes publicações no âmbito da cooperação, são expostas e comparadas as principais perspectivas teóricas já mencionadas, identificando seus aportes à compreensão do fenômeno cooperativo, seus pontos de convergência e de distanciamento. Elencamos os principais programas de pesquisa que têm dado desdobramento às premissas teóricas de Piaget e dos autores da Teoria da Escolha Racional.

  20. El análisis de la publicidad política desde la perspectiva de los estudios culturales

    Directory of Open Access Journals (Sweden)

    Rodolfo M. Gómez Castellanos

    2011-01-01

    perspectiva de investigación cualitativa; se aplican técnicas de investigación como la observación, entrevistas a profundidad y grupos de enfoque para observar los aspectos específicos del impacto de la publicidad política en la ideología de los ciudadanos.

  1. La creatividad como perspectiva educativa. Cinco ideas para pensar los contextos creativos de enseñanza y aprendizaje

    Directory of Open Access Journals (Sweden)

    Cecilia Elisondo, Romina

    2015-09-01

    Full Text Available En el presente ensayo planteamos un posicionamiento teórico para la construcción de una nueva perspectiva educativa que se sustente en los avances logrados en el campo de investigación de la creatividad, especialmente en los enfoques socio-culturales. Transformar la educación desde la creatividad supone reconocer las posibilidades creativas que tienen los actores, construir espacios para crear y resolver problemas, y propiciar interacciones con otros sujetos y con los objetos culturales. Es necesario crear una nueva forma de mirar la educación y generar innovaciones que atiendan a estos nuevos enfoques sobre lo educativo, las personas y los procesos de construcción de conocimientos en diferentes contextos culturales. En la primera parte revisamos mitos, fundamentos y definiciones necesarias para construir una nueva perspectiva educativa. Luego, desarrollamos cinco ideas para pensar los contextos creativos de enseñanza y aprendizaje desde la nueva perspectiva propuesta: aumentar las posibilidades educativas, invertir en educación, investir la educación, abrir la educación y generar indisciplina óptima. Por último, planteamos aperturas y desafíos de la nueva perspectiva al campo educativo y destacamos el papel de los docentes en la trasformación educativa y la generación de innovaciones pedagógicas. Las ideas presentadas emergen de estudios teóricos, investigaciones empíricas y experiencias educativas preliminares.

  2. LA CREATIVIDAD COMO PERSPECTIVA EDUCATIVA. CINCO IDEAS PARA PENSAR LOS CONTEXTOS CREATIVOS DE ENSEÑANZA Y APRENDIZAJE

    Directory of Open Access Journals (Sweden)

    Romina Cecilia Elisondo

    2015-01-01

    Full Text Available En el presente ensayo planteamos un posicionamiento teórico para la construcción de una nueva perspectiva educativa que se sustente en los avances logrados en el campo de investigación de la creatividad, especialmente en los enfoques socio-culturales. Transformar la educación desde la creatividad supone reconocer las posibilidades creativas que tienen los actores, construir espacios para crear y resolver problemas, y propiciar interacciones con otros sujetos y con los objetos culturales. Es necesario crear una nueva forma de mirar la educación y generar innovaciones que atiendan a estos nuevos enfoques sobre lo educativo, las personas y los procesos de construcción de conocimientos en diferentes contextos culturales. En la primera parte revisamos mitos, fundamentos y definiciones necesarias para construir una nueva perspectiva educativa. Luego, desarrollamos cinco ideas para pensar los contextos creativos de enseñanza y aprendizaje desde la nueva perspectiva propuesta: aumentar las posibilidades educativas, invertir en educación, investir la educación, abrir la educación y generar indisciplina óptima. Por último, planteamos aperturas y desafíos de la nueva perspectiva al campo educativo y destacamos el papel de los docentes en la trasformación educativa y la generación de innovaciones pedagógicas. Las ideas presentadas emergen de estudios teóricos, investigaciones empíricas y experiencias educativas preliminares.

  3. Trichinella : Epidemiología y nuevas perspectivas de inspección sanitaria en carnes de equino (II)

    OpenAIRE

    Fàbregas i Comadran, Xavier; Benito, J.

    2001-01-01

    Segunda parte del artículo sobre la Trichinella que obtuvo el primer premio del VI Concurso ADITSIC para trabajos relacionados con “La inspección y la calidad de la carne”. En esta ocasión se abordan las medidas preventivas de la enfermedad y las nuevas perspectivas de inspección sanitaria en carnes de equino.

  4. Biomolecules and Natural Medicine Preparations: Analysis of New Sources of Bioactive Compounds from Ribes and Rubus spp. Buds

    Directory of Open Access Journals (Sweden)

    Dario Donno

    2016-02-01

    Full Text Available It is well known that plants are important sources for the preparation of natural remedies as they contain many biologically active compounds. In particular, polyphenols, terpenic compounds, organic acids, and vitamins are the most widely occurring groups of phytochemicals. Some endemic species may be used for the production of herbal preparations containing phytochemicals with significant bioactivity, as antioxidant activity and anti-inflammatory capacities, and health benefits. Blackberry sprouts and blackcurrant buds are known to contain appreciable levels of bioactive compounds, including flavonols, phenolic acids, monoterpenes, vitamin C, and catechins, with several clinical effects. The aim of this research was to perform an analytical study of blackcurrant and blackberry bud-preparations, in order to identify and quantify the main biomarkers, obtaining a specific phytochemical fingerprint to evaluate the single botanical class contribution to total phytocomplex and relative bioactivity, using a High Performance Liquid Chromatograph−Diode Array Detector; the same analyses were performed both on the University laboratory and commercial preparations. Different chromatographic methods were used to determine concentrations of biomolecules in the preparations, allowing for quantification of statistically significant differences in their bioactive compound content both in the case of Ribes nigrum and Rubus cultivated varieties at different harvest stages. In blackcurrant bud-extracts the most important class was organic acids (50.98% followed by monoterpenes (14.05%, while in blackberry preparations the main bioactive classes were catechins (50.06% and organic acids (27.34%. Chemical, pharmaceutical and agronomic-environmental knowledge could be important for obtaining label certifications for the valorization of specific genotypes, with high clinical and pharmaceutical value: this study allowed to develop an effective tool for the natural

  5. Toward an Accurate Modeling of Hydrodynamic Effects on the Translational and Rotational Dynamics of Biomolecules in Many-Body Systems.

    Science.gov (United States)

    Długosz, Maciej; Antosiewicz, Jan M

    2015-07-01

    Proper treatment of hydrodynamic interactions is of importance in evaluation of rigid-body mobility tensors of biomolecules in Stokes flow and in simulations of their folding and solution conformation, as well as in simulations of the translational and rotational dynamics of either flexible or rigid molecules in biological systems at low Reynolds numbers. With macromolecules conveniently modeled in calculations or in dynamic simulations as ensembles of spherical frictional elements, various approximations to hydrodynamic interactions, such as the two-body, far-field Rotne-Prager approach, are commonly used, either without concern or as a compromise between the accuracy and the numerical complexity. Strikingly, even though the analytical Rotne-Prager approach fails to describe (both in the qualitative and quantitative sense) mobilities in the simplest system consisting of two spheres, when the distance between their surfaces is of the order of their size, it is commonly applied to model hydrodynamic effects in macromolecular systems. Here, we closely investigate hydrodynamic effects in two and three-body systems, consisting of bead-shell molecular models, using either the analytical Rotne-Prager approach, or an accurate numerical scheme that correctly accounts for the many-body character of hydrodynamic interactions and their short-range behavior. We analyze mobilities, and translational and rotational velocities of bodies resulting from direct forces acting on them. We show, that with the sufficient number of frictional elements in hydrodynamic models of interacting bodies, the far-field approximation is able to provide a description of hydrodynamic effects that is in a reasonable qualitative as well as quantitative agreement with the description resulting from the application of the virtually exact numerical scheme, even for small separations between bodies. PMID:26068580

  6. Biomolecules and Natural Medicine Preparations: Analysis of New Sources of Bioactive Compounds from Ribes and Rubus spp. Buds.

    Science.gov (United States)

    Donno, Dario; Mellano, Maria Gabriella; Cerutti, Alessandro Kim; Beccaro, Gabriele Loris

    2016-01-01

    It is well known that plants are important sources for the preparation of natural remedies as they contain many biologically active compounds. In particular, polyphenols, terpenic compounds, organic acids, and vitamins are the most widely occurring groups of phytochemicals. Some endemic species may be used for the production of herbal preparations containing phytochemicals with significant bioactivity, as antioxidant activity and anti-inflammatory capacities, and health benefits. Blackberry sprouts and blackcurrant buds are known to contain appreciable levels of bioactive compounds, including flavonols, phenolic acids, monoterpenes, vitamin C, and catechins, with several clinical effects. The aim of this research was to perform an analytical study of blackcurrant and blackberry bud-preparations, in order to identify and quantify the main biomarkers, obtaining a specific phytochemical fingerprint to evaluate the single botanical class contribution to total phytocomplex and relative bioactivity, using a High Performance Liquid Chromatograph-Diode Array Detector; the same analyses were performed both on the University laboratory and commercial preparations. Different chromatographic methods were used to determine concentrations of biomolecules in the preparations, allowing for quantification of statistically significant differences in their bioactive compound content both in the case of Ribes nigrum and Rubus cultivated varieties at different harvest stages. In blackcurrant bud-extracts the most important class was organic acids (50.98%) followed by monoterpenes (14.05%), while in blackberry preparations the main bioactive classes were catechins (50.06%) and organic acids (27.34%). Chemical, pharmaceutical and agronomic-environmental knowledge could be important for obtaining label certifications for the valorization of specific genotypes, with high clinical and pharmaceutical value: this study allowed to develop an effective tool for the natural preparation quality

  7. Labelling techniques of biomolecules for targeted radiotherapy. Final report of a co-ordinated research project 1998-2002

    International Nuclear Information System (INIS)

    optimization of radiolabelling techniques with beta emitting radioisotopes, including quality control procedures and evaluation of the labelled products in in vitro and in vivo models. Biomolecule carriers that were considered for investigation included somatostatin analogues like lanreotide, Tyr-octreotide, ior-P1394 and vasointestinal peptide (VIP), as well as anti-CEA monoclonal antibody. Using either the bifunctional chelate approach or direct reductive exposure of -SH groups, labelling of these biomolecules with therapeutic radionuclides was pursued. Through these attempts it was expected to identify one or two agents with high radiochemical purity and labelling efficiency for further evaluation. Promising agents would be selected for further investigation using biodistribution studies in animals and uptake in tumour bearing animals. Fifteen selected research institutes from Argentina, Austria, Brazil, Cuba, Greece, Finland, Hungary, India, Italy, Mexico, Pakistan, Peoples Republic of China, Romania, Thailand and Uruguay with recognized expertise in the field of therapeutic radionuclides and radiopharmaceutical research were selected to participate in the CRP. The first research co-ordination meeting to plan the work and define the research protocols to be investigated was held in Milan, Italy in July 1998. At this meeting it was decided to concentrate the efforts on two radionuclides, 188Re and 90Y, which are produced by generator systems and result in carrier free products; lanreotide was selected as a model peptide. Synthesis of the bifunctional chelating agent DOTA was also recommended for the labelling of biomolecules with 90Y. The development of the corresponding coupling techniques, optimization of protocols for direct and indirect labelling of lanreotide and anti-carcino embryonic antigen (CEA) monoclonal antibody and in vitro evaluation in cell lines and membrane receptors were also included in the work plan for the following period. IgG labelled with 131I and

  8. ¿A quién le importa? Radio especializada musical en España desde la perspectiva del servicio público

    OpenAIRE

    Costa Gálvez, Dolores

    2015-01-01

    La presente tesis tiene como objetivo el estudio de la radio especializada musical en España desde la perspectiva del servicio público. Este objeto de estudio puede abordarse desde múltiples perspectivas y en esta investigación se hace desde el punto de vista del emisor, ya que la motivación es conocer cómo se define el servicio público desde la radio especializada musical. Es esta una perspectiva poco estudiada, dado que los estudios sobre radio y servicio público se han centrado en la relac...

  9. Modelos de características para la gestión de la variabilidad en las perspectivas de los procesos de negocio

    OpenAIRE

    AYORA ESTERAS, CLARA; Torres Bosch, Maria Victoria; Pelechano Ferragud, Vicente

    2012-01-01

    Construir modelos de Procesos de Negocio (PN) implica grandes retos, especialmente cuando los PN varían. Además, éstos pueden verse desde diferentes perspectivas, e.g., la perspectiva de comportamiento (i.e., control de flujo), la organizacional (i.e., distribución de recursos), o la informacional (i.e., flujo de datos). Dependiendo del contexto en el que el PN se lleva a cabo, es posible encontrar variabilidad en cualquiera de estas perspectivas. A pesar de que existen propuestas para modela...

  10. Percepção e intenção ética : análise do posicionamento ético na perspectiva do consumidor

    OpenAIRE

    Freitas, Carlos Roberto Gouveia de

    2012-01-01

    Do ponto de vista conceptual, a ética nos negócios ou ética empresarial tem sido apontada como fundamental para o desenvolvimento de estratégias focadas no interesse comum tanto de empresas como dos consumidores. Os interesses de todos os stakeholders têm de ser garantidos tanto na perspectiva da geração de lucro, como na perspectiva da satisfação de necessidades e não menos importante, na perspectiva de retorno à comunidade. A actividade de marketing está muito sujeita a aprec...

  11. Análisis crítico de las perspectivas y recursos para la trata de personas con fines de explotación sexual en Barcelona

    OpenAIRE

    Peixoto Santos, Sandra

    2012-01-01

    En este artículo presento abordajes en relación a la intervención sobre el fenómeno de la trata de personas con fines de explotación sexual en Barcelona desde la perspectiva de los profesionales implicados en los diferentes recursos existentes. Primeramente, considero las diferencias entre trata y prostitución, noción de víctima y perspectiva de género, y la influencia de la globalización en el fenómeno. En seguida, presento el contraste de perspectivas de los profesionales entrevistados en r...

  12. Análisis del principio de precaución en Derecho internacional público: perspectiva universal y perspectiva regional europea Análisis del principio de precaución en Derecho internacional público: perspectiva universal y perspectiva regional europea

    Directory of Open Access Journals (Sweden)

    Patricia Jiménez de Parga y Maseda

    2003-01-01

    Full Text Available This article analyses the precautionary principIe from the perspective of Public International Law, and, more specifically, following International Environmental Law.The first section centers upon three topics the definition of the main elements of the principle its status in international law and the distinction between precaution and prevention. The second section focuses an Community law and tries to assert if the European Union has contributed to a definition of the precautionary Principle as well as it documents its expansion into other areas.La autora de este estudio analiza el principio de precaución desde la perspectiva del Derecho internacional público y desde el Derecho internacional del medio ambiente. El plan de trabajo consiste en analizar principio de precaución tanto desde una perspectiva universal (parte primera como desde la regional europea (parte segunda. En la primera estudia el principio de precaución desde el ángulo de los principios estructurales del Derecho internacional del medio ambiente (punto A; establece los elementos definitorios del principio de precaución (punto B; fija el status del principio de precaución en el derecho nacional del medio ambiente (punto C, y se pregunta acerca de la distinción y de la articulación jurídica de los principios de prevención y de precaución (punto D. En la segunda sitúa el principio de precaución desde al ángulo del Derecho de la Unión Europea, y de forma más concreta, en tanto que uno de los principios jurídicos que informan el principio estructural de la protección ambiental en el Derecho de la Unión Europea (punto A; averigüa si el Derecho comunitario europea ha procedido o no a una definición propia del principio de precaución (punto B, y ve cómo el principio de precaución se está extendiendo a otros ámbitos (punto C. Una vez analizado el principio de precaución tanto desde una perspectiva universal como desde otra de signo particular, la autora

  13. Ion Binding to Biomolecules

    Czech Academy of Sciences Publication Activity Database

    Lund, M.; Heyda, Jan; Jungwirth, Pavel

    New Jersey : World Scientific, 2010 - (Kunz, W.), s. 217-230 ISBN 978-981-4271-57-8 Institutional research plan: CEZ:AV0Z40550506 Keywords : proteins * salts * molecular dynamics Subject RIV: CF - Physical ; Theoretical Chemistry

  14. Structure & properties of biomolecules

    CERN Document Server

    Duchesne, J

    2009-01-01

    The Advances in Chemical Physics series provides the chemical physics and physical chemistry fields with a forum for critical, authoritative evaluations of advances in every area of the discipline. Filled with cutting-edge research reported in a cohesive manner not found elsewhere in the literature, each volume of the Advances in Chemical Physics series serves as the perfect supplement to any advanced graduate class devoted to the study of chemical physics.

  15. A Revista Brasileira de Enfermagem: apontando perspectivas para sua análise

    Directory of Open Access Journals (Sweden)

    Mirian Santos Paiva

    2002-02-01

    Full Text Available Esse ensaio propõe algumas reflexões sobre o modo de analisara Revista Brasileira de Enfermagem. A Revista, instrumento de disseminação de conhecimentos e ideologia da enfermagem, tem sido objeto de poucos estudos na profissão. No ensaio, as autoras tomam como referência teórica o triângulo da significação de Pierre Lévy e aspectos da teoria feminista como pontos de partida para a análise proposta. Numa perspectiva para além do formal, a Revista pode e deve ser analisada enquanto um objeto que produz, na sua relação com as enfermeiras, elementos que compõem a cultura, o conhecimento e a simbologia da enfermagem brasileira.

  16. Naturologia e a emergência de novas perspectivas na saúde

    OpenAIRE

    Barros, Nelson Filice de; Leite-Mor, Ana Cláudia Moraes Barros

    2011-01-01

    O objetivo deste trabalho é refletir sobre a Naturologia como novo agente no campo da saúde brasileiro e suas peculiaridades relativas à convergência com a perspectiva social atual e contribuições à problemática contemporânea da saúde. Para isso, debatemos com a ciência moderna e suas transformações, a partir da “revolução fenomenológica”, que refuta o objetivismo, a neutralidade e a separação sujeito-objeto, e da “revolução quântica”, que atestou a insuficiência da mecânica clássica e a não-...

  17. La educación a distancia: una perspectiva crítica

    Directory of Open Access Journals (Sweden)

    Edith Litwin

    1993-06-01

    Full Text Available En este capítulo nos proponemos revisar la educación a distancia desde esta perspectiva, porque entendemos que el crecimiento de la modalidad necesita, además de sus consideraciones o caracterizaciones,un análisis que le permita encontrar nuevas respuestas y definiciones. No se trata de señalar limitaciones descartando posibilidades para la educación a distancia. Esa sería una propuesta de trabajo llevada a cabo desde el sentido común. Se trata, en cambio, de recoger los resultados de diferentes investigadores en el campo, las experiencias de las implementaciones de programas o proyectos en la modalidad y los resultados de investigaciones evaluativas. A la luz de la teoría y la práctica, revisar lo dicho y hecho con el objeto de encontrar una nueva manera de crecer.

  18. Las metodologías participativas desde la perspectiva sociopráxica

    OpenAIRE

    Esteban Ramos Muslera

    2012-01-01

    Concebir las metodologías participativas desde la perspectiva sociopráxica permite plantear un modelo científicamente válido de investigación social, capaz de superar las dicotomías clásicas existentes entre los pares conocimiento teórico y práctico, y objeto y sujeto de investigación. En este artículo se da cuenta de la fundamentación teórica de la producción de conocimiento participativo –partiendo del entendimiento del ser humano como sistema práxico, organizacionalmente cerrado y energéti...

  19. Los discursos en la salud pública desde una perspectiva de género

    OpenAIRE

    Isa, Luciana Jimena

    2014-01-01

    El presente artículo tiene como propósito dar cuenta del avance del trabajo en un proceso de investigación que aborda la construcción y análisis de discursos desde una perspectiva de género, tomando como campo material los discursos médicos en áreas de salud reproductiva y pediátrica. Específicamente, se busca exponer los modos de organización de las instancias de problematización que llevan a la construcción del problema de investigación y que dan paso a la elaboración del corpus analítico, ...

  20. La globalización de la Amazonía: una perspectiva andina

    OpenAIRE

    Fontaine, Guillaume

    2006-01-01

    En este artículo presentamos el contexto histórico, social, político y económico que enmarca a la cuenca amazónica contemporánea, desde la perspectiva de los países andinos. En la introducción recordamos algunos datos básicos sobre la situación geográfica y demográfica de la región. Luego presentamos las principales etapas de la ocupación humana del espacio amazónico, desde la Conquista hasta la irrupción del capitalismo. Dedicamos la segunda parte a la internacionalización de la agenda amazó...

  1. La innovación tecnológica desde una perspectiva evolutiva

    OpenAIRE

    Benavides Óscar A.

    2004-01-01

    Este artículo analiza el proceso de innovación tecnológica desde la economía política, específicamente, desde la perspectiva evolutiva.
    Se adopta el enfoque schumpeteriano en el cual el proceso de innovación tecnológica puede ser visto como un proceso de aprendizaje. En ese sentido, la innovación tecnológica representa un cambio en el conocimiento y, por ende, tiene un carácter epistemológico. Esta conceptualización, junto con el análisis histórico del proceso de innovación tecnoló...

  2. Enfoques y perspectivas de los estudios sociales sobre la familia en Colombia

    Directory of Open Access Journals (Sweden)

    María Himelda Ramírez

    2012-08-01

    Full Text Available En este artículo se propone una lectura de algunos de los énfasis de los estudios recientes sobre la familia en Colombia, con el propósito de apreciar una visión de conjunto del estado de las discusiones sobre esa compleja realidad constituída por las familias colombianas. Se parte de la consideración del hecho de que ante todo ha interesado la perspectiva del presente, asociada a los problemas y conflictos de los hogares colombianos en una etapa de tránsito traumática, en la que se intensificaron los movimientos de las poblaciones, y se produjo una reorganización espacial de los habitantes del país, de una predominancia rural a una urbana, en un contexto de violencia que se acentúa y diversifica.

  3. Cosmopolíticas: Perspectivas antropológicas (Montserrat Cañedo, Ed.

    Directory of Open Access Journals (Sweden)

    Marce Casado

    2013-09-01

    Full Text Available Una disciplina como la antropología social y cultural ha de proveerse de manuales y monografías que surtan de recursos didácticos, de referentes para el aprendizaje y de familiarización de los antropólogos con la metodología etnográfica. Cosmopolíticas es una prueba de ese esfuerzo por hacernos llegar a todos los interesados las variadas perspectivas desde las que se conforma el trabajo de campo del etnógrafo, los planteamientos y avatares a veces inesperados de los que se nutre el proceso etnográfico, y una muestra de los modos en que las personas se dotan de organización e instituciones en las sociedades de todo el mundo.

  4. Sexualidade, Gênero e Poder – educação numa perspectiva emancipatória

    Directory of Open Access Journals (Sweden)

    Tereza Cristina Fagundes

    2014-03-01

    Full Text Available Este ensaio apresenta uma análise sobre sexualidade, gênero e poder e a importância da educação para a construção do empoderamento das mulheres.  Reflete sobre ações educativas na escola, com vistas à educação para a sexualidade numa perspectiva emancipatória. Palavras-chave: sexualidade, gênero, empoderamento.  ABSTRACT: This essay presents an analysis about sexuality, gender and power and the importance of education for the construction of the empowerment of women. Reflects on educational activities at school, with a view to education for sexuality in an emancipatory perspective. Keywords: sexuality, gender, empowerment.

  5. Tendências e perspectivas das teorias locacionais no Capitalismo contemporâneo

    Directory of Open Access Journals (Sweden)

    Rhalf Magalhães Braga

    2008-01-01

    Full Text Available O objetivo deste artigo é resgatar o tema das teorias locacionais e assim contribuir para o debate na Geografia, debate este um tanto esquecido atualmente. Destacamos as principais tendências do enfoque locacional: neoclássico, comportamental, sistêmico e marxista. Além disso, abordamos algumas perspectivas atuais, não só na Geografia, como também na Administração, Economia e Sociologia. Notase que as abordagens caminham de um pensamento mais abstrato e generalizante, passando por uma consideração dos problemas sociais até um olhar mais regional e focado no paradigma do capitalismo informacional.

  6. Criminalidade violenta: por uma nova perspectiva de análise

    Directory of Open Access Journals (Sweden)

    Luís Antonio Machado da Silva

    1999-11-01

    Full Text Available O artigo aborda o problema da criminalidade violenta urbana no Brasil após a década de setenta, procurando apresentar uma nova perspectiva de análise. Seu argumento é que as interpretações correntes, que vinculam o aumento da criminalidade, especialmente a organizada, à crise institucional são inadequadas, pois não consideram a especificidade do problema, tanto do ponto de vista teórico como, e principalmente, do ponto de vista prático. A criminalidade organizada é uma realidade social com lógica própria, até agora não estudada, e que funciona com certa independência em relação a outros problemas e fenômenos sociais, como a "crise do Estado".

  7. A perspectiva CTSA nos manuais escolares de ciências da natureza do 2º CEB

    OpenAIRE

    Fernandes, Isabel Marília Borges

    2011-01-01

    Perante o rápido avanço da Ciência e da Tecnologia nos dias actuais, a Educação Científica torna-se uma necessidade para todos, visando a participação da cidadania na tomada de decisões, principalmente em implicações dos avanços científicos e tecnológicos que podem colocar em risco as pessoas e o meio ambiente. Assim, a perspectiva CTSA, uma das linhas mais inovadoras e actual no ensino das ciências, é preconizada por Programas e Orientações Curriculares do Ensino Básico, nomeadamente, no ens...

  8. Marañas con distintos acentos: Género y Sexualidad en la Perspectiva Interseccional

    Directory of Open Access Journals (Sweden)

    Raquel (Lucas Platero [entrevistado

    2013-06-01

    Full Text Available En las siguientes líneas reproducimos una conversación previa a la presentación del libro recientemente editado por Lucas Platero Intersecciones: cuerpos y sexualidades en la Encrucijada (2012. Barcelona: Bellaterra, en la librería La Marabunta con el acto “Cocinando Debates interseccionales: subculturas lésbicas butch/femme, diásporas queer y debates queer” (20 abril de 2013. Hablamos de la perspectiva interseccional y entre otras cosas, relaciones entre la teoría y la praxis, pedagogía o de la capacidad transformadora de las políticas de género y sexualidad.

  9. El cambio climático y la inequidad en Colombia: tendencias recientes y perspectivas futuras

    OpenAIRE

    Mora Motta, Alejandro

    2014-01-01

    Esta investigación se enfoca principalmente en el análisis de las relaciones entre el fenómeno del cambio climático (CC) y la inequidad económica a nivel teórico y para el caso de Colombia. En primer lugar, se procura discutir las perspectivas e identificar las posibles interacciones entre los dos fenómenos a nivel teórico. En segundo término, se plantea un análisis de la incidencia de la inequidad en la generación de gases de efecto invernadero para el caso colombiano y, en tercer lugar, se ...

  10. Die Aufzeichnungen des Malte Laurids Brigge: novas perspectivas de interpretação

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    Renata Martins

    2012-12-01

    Full Text Available O objetivo deste texto é analisar a experiência do estranho no romance Die Aufzeichnungen des Malte Laurids Brigge, de Rainer Maria Rilke, através de novas perspectivas de interpretação apoiadas, por exemplo, nas teorias psicanalíticas de Sigmund Freud. Vivendo em uma cidade estrangeira (Paris, com a qual ainda não se identifica, o protagonista do romance, Malte Laurids Brigge, descobre um mundo interior novo através de seu choque com experiências do estranho nesse milieu. A revelação de recordações de sua infância e a projeção de seu ego em leituras de narrativas alheias são seus métodos para buscar e afirmar sua identidade.

  11. Sociedad, identidad y defensa de lo propio: desde una perspectiva de la bioética

    Directory of Open Access Journals (Sweden)

    Miguel-Héctor Fernández-Carrión

    2012-12-01

    Full Text Available En la comprensión del individuo o sujeto social se puede centrar el análisis sobre la identidad, en sus variantes individual y colectiva, hasta adentrarse en el estudio de la defensa de lo propio y/o común, a lo que se le añade la perspectiva de la bioética, para el entendimiento de algunos aspectos específicos del ser humano en el devenir de la/su vida. Con el desarrollo de las nuevas tecnologías en la sociedad de la comunicación/información la aplicación de una visión bioética a la acción humana determina unas especificidades de la identidad, en los dos casos especiales analizados en torno a la identidad civil y la identidad de filiación.

  12. Pensando la sociedad desde la perspectiva teórica de Niklas Luhmann

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    Guillermina Ramírez

    2008-01-01

    Full Text Available Sociedades caracteriza das por un alto grado de complejidad y diferenciación que rebasan los marcos teóricos con los cuales se le han interpretado, dan lugar a nuevas perspectivas. Cobra sentido el objeto de este trabajo, el cual es analizar la propuesta teórica de Niklas Luhmann. Los contenidos y alcances se extraen directamente de su obra Sistemas Sociales. Lineamientos para una teoría general: complementados con opiniones que sobre el autor, se llevan a cabo en los ambientes científicos y académicos. Conceptos diversos permiten analizar la transición en términos de continuidad y ruptura con el pensamiento sociológico clásico para concluir con sus principales aportes.

  13. Imaginário & ciência: novas perspectivas do conhecimento na contemporaneidade

    OpenAIRE

    Ana Maria Dalla Zen

    2011-01-01

    Reflete sobre o conhecimento contemporâneo, a partir de uma comparação entre a ciência cartesiana e o paradigma emergente, com base nas idéias de Ilya Prigogine. Destaca a mudança provocada pela inclusão da subjetividade na construção do conhecimento, numa perspectiva de conexão entre a emoção, a paixão e a razão como estratégia para compreensão da realidade. Analisa os conceitos de disciplinaridade, interdisciplinaridade e transdisciplinaridade. Destaca o papel das emoções na construção do ...

  14. Problemas y perspectivas de la investigación psicoeducacional en el Perú

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    Iván Montes Iturrizaga

    1992-12-01

    Full Text Available El presente estudio pretende ofrecer una reflexión general sobre la problemática de la investigación psicoeducacional en el Perú. Esto nos lleva inevitablemente a plantear problemáticas que no son exclusivas de la psicología educacional, sino que atañe a la psicología peruana en su totalidad. Se incide de forma especial en la formación del psicólogo, los reglamentos de investigación y la necesidad del psicólogo educacional de nutrirse permanentemente de la praxis educativa. Se analizan perspectivas y posibles caminos de solución.

  15. La investigación para la paz y la perspectiva de los sistemas-mundo

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    Jose Maria Tortosa

    2015-08-01

    Full Text Available El primer propósito de este capítulo es el de explorar algunas de las formas en que el enfoque de los sistemas-mundo puede ser aplicado a un campo aparentemente distante como es el de la investigación para la paz. La razón es sencilla: se parte de que el valor de una teoría puede “medirse” viendo su fecundidad y la capacidad que muestre de arrojar nueva luz sobre problemas y temas ajenos a la misma. De ahí se concluye que una buena forma de colaborar en una colección de ensayos en honor a Immanuel Wallerstein es la de mostrar que el enfoque que él iniciara proporciona ideas relevantes cuando se aplica a campos diferentes al original y da respuestas igualmente importantes a los problemas planteados desde otras perspectivas.

  16. Situación actual y perspectivas de la Psicoterapia en España.

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    Juan Carlos Duro Martínez

    1994-01-01

    Full Text Available Para dar una visión global de la situación de la psicoterapia en España haremos un breve recorrido histórico de los tres aspectos que consideramos fundamentales para entender en qué estado se encuentra la psicoterapia en nuestro país y qué perspectivas se plantean cara a la integración en la Comunidad Europea. Estos tres aspectos serán: desarrollo e implantación de las teorías sobre la salud y la enfermedad mental; roles y organizaciones profesionales en relación a la psicoterapia y discusión sobre la práctica de la psicoterapia.

  17. SALUD MENTAL: UN ABORDAJE DESDE LA PERSPECTIVA ACTUAL DE LA PSICOLOGÍA DE LA SALUD

    Directory of Open Access Journals (Sweden)

    Moisés Mebarak

    2009-01-01

    Full Text Available Este artículo está basado en un estudio estado del arte acerca del entendimiento actual que se tiene sobre el concepto de salud mental, especialmente desde la perspectiva de la psicología de la salud. Con el fin de ilustrar este campo, se presentan algunos aportes y/o investigaciones tanto a nivel general como de la región costa Caribe colombiana. Se ha encontrado que el concepto de salud mental implica el desarrollo de estilos de vida y de características personales, interpersonales, sociales y laborales que apuntan a una idea integrada de bienestar biopsicosocial. De esta forma, la salud mental se entiende que sobrepasa y no es reducida a la simple ausencia de síntomas.

  18. Biologia do envelhecimento: teorias, mecanismos e perspectivas Biology of aging: theories, mechanisms, and perspectives

    Directory of Open Access Journals (Sweden)

    Ilka Nicéia D'Aquino Oliveira Teixeira

    2010-09-01

    Full Text Available O artigo apresenta uma revisão das teorias biológicas do envelhecimento e discute os mecanismos relevantes para explicar o processo. Iniciando com as teorias evolutivas, o texto explora os mecanismos moleculares-celulares e apresenta a perspectiva das teorias sistêmicas. O conhecimento sobre a senescência desenvolve-se na direção de uma abordagem integrativa. A complexidade etiológica do fenômeno é um desafio para os pesquisadores.Abstract The article reviews the major biological theories of aging, and discusses the most relevant mechanisms to explain the aging process. It begins with the evolutionary theories, explores the molecular-cellular mechanisms, and presents the perspective of the systemic theories. The complex etiology of aging is a challenge to the researchers. The knowledge on that phenomenon develops towards an integrative approach.

  19. Motivaciones y expectativas profesionales. Análisis desde la perspectiva de género.

    OpenAIRE

    Candela Agulló, Carlos

    2007-01-01

    RESUMEN Este trabajo se plantea como objetivo principal la comprensión de los motivos que llevan a hombres y mujeres a elegir y desempeñar profesiones diferentes. La aproximación al estudio de esta cuestión se realiza desde dos perspectivas fundamentales, la psicología del género y la psicología de la motivación. En primer lugar, se realiza una revisión de la situación de la mujer en la sociedad actual, especialmente en los ámbitos educativo y laboral. La segregación horizontal de géner...

  20. Diálogo de las perspectivas de perfil conceptual y conglomerados de relevancia

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    Rosa I. Pedreros-M

    2013-01-01

    Full Text Available El presente artículo forma parte del desarrollo de la investiga - ción doctoral titulada “Perfil conceptual del calor en comu - nidades culturalmente diferenciadas” y tiene como intención socializar las perspectivas de perfil conceptual y conglomera - dos de relevancia como referentes teóricos y metodológicos que permitan proponer nuevas opciones para pensar la ense - ñanza-aprendizaje de las ciencias o la educación en ciencias, que observen los modos de pensar y hablar de los estudiantes y las relaciones entre la cultura local y el conocimiento escolar. Se exponen el origen, los referentes, las consideraciones so - bre la enseñanza-aprendizaje de las ciencias y las razones para investigar desde estas perspectivas.Nuestro país está conformado por comunidades culturalmen - te diferenciadas, lo cual constituye un reto y desafío para la comunidad académica. Exige, entre otras cosas, propiciar una enseñanza-aprendizaje de las ciencias que tenga en cuenta la diversidad de sistemas de conocimiento, las visiones de mun - do y los modos de pensar y hablar de las comunidades con las que se realiza la acción pedagógica. En este sentido, los perfiles conceptuales y los conglomerados de relevancia se constituyen en referentes teóricos y metodológicos que per - miten reconocer el contexto cultural, las creencias, los valores y las significaciones del entorno físico y natural que tienen los estudiantes.

  1. O cuidado a pessoas com HIV/aids na perspectiva de profissionais de saude

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    Carla Sofia de Oliveira Sousa

    2013-08-01

    Full Text Available Este estudo teve por objetivo compreender o cuidado as pessoas com HIV/aids, na perspectiva de profissionais de saúde, em Portugal. Foi desenvolvido através do método da história oral, de Thompson, com a participação de 22 profissionais de saúde. Os dados foram obtidos através de entrevista semiestruturada e analisados com base na perspectiva de coletânea de narrativas, propostas pelo autor com o apoio do programa QSR NVivo. Os aspectos éticos foram obedecidos ao longo do estudo. O cuidado foi agrupado em três dimensões: cognitiva, afetiva-relacional e técnico-instrumental. A dimensão cognitiva destacou-se no período da revelação do diagnóstico de HIV/aids e ao longo da evolução da doença. A dimensão afetivo-relacional foi transversal e valorizada em todo o processo, desde o diagnóstico até à morte das pessoas com HIV/aids. A dimensão técnico-instrumental foi mais expressiva na fase mais avançada da doença, em situação de dependência e de terminalidade. Diante do exposto, podemos concluir que estas três dimensões são fundamentais para o cuidado à pessoa com HIV/aids.

  2. Internacionalização de empresas: perspectivas teóricas e agenda de pesquisa

    Directory of Open Access Journals (Sweden)

    Eda Castro Lucas de Souza

    2012-07-01

    Full Text Available DOI: http://dx.doi.org/10.5007/2175-8077.2012v14n33p103O objetivo deste ensaio é identificar e discutir a produção científica sobre internacionalização de empresas para apresentar uma agenda de pesquisa concernente ao tema a partir das direções apontadas no estado da arte dos estudos desse fenômeno. Adicionalmente, este texto busca delinear e caracterizar as perspectivas teóricas que predominam nessa produção. Por meio de revisão da produção acadêmica brasileira e estrangeira sobre internacionalização, publicada no período de janeiro de 2005 a setembro de 2011, foram selecionados 141 artigos, identificando-se a carência de trabalhos que promovessem uma discussão direta sobre a relação entre  internacionalização e cultura, especialmente no que concerne às iniciativas brasileiras. A análise dos textos selecionados permitiu uma taxonomia dos estudos em três perspectivas teóricas: econômica, comportamental e cultural. Ao final, e com apoio na análisedos artigos publicados, propõe-se uma agenda de pesquisa a respeito do tema internacionalização de empresas, elaborada a partir das lacunas apontadas no estado da arte dos estudos sobre esse fenômeno.

  3. LA ECO­ POIESIS COMO FUNDAMENTO DE UNA PERSPECTIVA AMBIENTAL PARA LA ADMINISTRACIÓN

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    Arango Fernández Wilfer Ignacio

    2008-07-01

    Full Text Available La realidad no es tan simple como se quisiera. Es compleja de modo que no puede ser siempre comprendida bajo simples reglas. Por ello, las exploraciones de la ciencia han catalizado una profunda re­conceptualización del universo. Una nueva manera integral de ver, pensar y conocer el mundo ha sido introducida. La nueva perspectiva busca entender sistemas que cambian de manera s no propia s para una visión línea l. La s organizaciones, particular m ente las empresariales, están sujetas a los mismos principios de la nueva ciencia, y uno de los principales impactos en la aplicación de los conceptos de la complejidad yace en la forma como estas son percibidas. En el siglo 21, las empresas no serán por más tiempo administradas eficientemente por objetivos o perspectivas lineales y rígidas. Los estados de caos conducen a la creatividad, a la innovación y a la autoorganización ; desorden, disipación y cambio son la regla, no más la excepción. Este artículo propone el entendimiento de las organizaciones en términos de una percepción holística, confrontando las visiones tradicionales y explorando la relevancia del nuevo paradigma en el campo de relación entre organizaciones y medio ambiente. Se proporciona un panorama del significado del cambio de percepción, seguido por la manera en la cual las teorías (complejidad, eco­poiesis, estructuras disipativas, organizaciones vivas pueden ser aplicadas en el campo administrativo.

  4. El estudio de la poesía desde una perspectiva cognitiva: panorama y propuesta

    Directory of Open Access Journals (Sweden)

    Luján Atienza, Ángel Luis

    2006-06-01

    Full Text Available This paper intends to be a survey of the cognitive science applied to literary studies, specifically to poetry. Cognitive science has been developed in the English linguistic area and this paper is an attempt to introduce this view in the Hispanic area. In my view, it is necessary to include the literary analysis in the general field of the cognitive linguistics and use the Relevance Theory. The enfasis is on the capacity of the human mind for understanding text extracting information from the textual sources, in opposition to the relativistic view. The point is illustrate with an example of Gongora.Este artículo pretende ser una revisión de la aplicación de la perspectiva cognitiva, de amplio desarrollo en psicología y en antropología, al estudio de la literatura y en concreto al género de la poesía lírica. Este tipo de estudios se ha llevado a cabo sobre todo en el área lingüística anglo-sajona y el presente trabajo se presenta como una propuesta para introducir esta perspectiva en el ámbito hispánico. Para ello se aboga por un estudio de la lírica dentro del estudio general de la lingüística cognitiva, teniendo en cuenta siempre la teoría de la relevancia. Se pone especial acento en la capacidad de la mente humana para comprender textos a partir de informaciones puramente textuales frente al relativismo de las posturas convencionalistas que creen que el proceso de comprensión se lleva a cabo por convenciones sociales e institucionales. Un ejemplo de Góngora sirve de ilustración de cómo puede ser un acercamiento del tipo que se propone.

  5. Liberalismo y género: una perspectiva contextual Liberalismo e gênero: uma perspectiva contextual Liberalism and gender: a contextual persepctive

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    Soledad Escalante Beltrán

    2006-06-01

    Full Text Available El presente artículo pretende, desde una perspectiva liberal, discutir contextualmente la categoría de género. En los seis apartados que lo componen, se realiza una crítica profunda de la ciencia social pero desde una óptica menos rígida en el planteamiento de categorías dicotómicas excluyentes como masculino-femenino, racional-afectivo, privado-público, o liberal - comunitario, por mencionar algunos tópicos centrales en los que se han suscitado varios de los debates sobre género. La metodología utilizada es la comparativa, a partir de la cual se analizan autores como Kohlberg, Gilligan, Rawls, entre otros. Una de las principales conclusiones a la que se arriba en este artículo es que los tradicionales esquematismos, aun existentes en la actualidad, hacen muy difícil la posibilidad de alcanzar consensos amplios y postergan riesgosamente el tratamiento de problemas prácticos como los que, en el caso peruano, suponen la traducción del discurso de equidad en acciones y prácticas cotidianas concretas que permitan a los ciudadanos un real acceso a la justicia.Este artigo pretende, desde uma perspectiva liberal, discutir contextualmente a categoria gênero. Nas seis seções que o compõem procura realizar uma crítica profunda da ciência social, a partir, porém, de uma ótica menos rígida no tratamento de categorias dicotômicas excludentes tais como masculino-feminino, racional-afetivo, privado-público, liberal-comunitário, para mencionar alguns dos tópicos centrais suscitados pelos vários debates sobre gênero. A metodologia utilizada é a comparativa, a partir da qual se analisam autores como Kolberg, Gilligan, Rawls, entre outros. Uma das principais conclusões alcançadas neste trabalho é a de que os esquemas teóricos tradicionais, ainda existentes, dificultam a possibilidade de se alcançar amplos consensos e atrasam o equacionamento de problemas práticos, tais quais, no caso peruano, aqueles oriundos da tradução do

  6. Importancia de la perspectiva familiar en la clínica psiquiátrica infantil. La intervención familiar.

    Directory of Open Access Journals (Sweden)

    Fernando Cabaleiro Fabeiro

    1981-01-01

    Full Text Available En este trabajo haré una muy breve introducción de la perspectiva familiar, veré luego cómo esta perspectiva puede ser útil en la comprensión del síntoma V del diagnóstico, -en el establecimiento de un pronóstico evolutivo, -V, finalmente, en el tratamiento, a través de la intervención familiar.

  7. Análisis de la acción humana: la convergencia de dos perspectivas contemporáneas

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    Pepi Patrón

    1992-06-01

    Full Text Available Como el título indica, el texto que aquí presento tiene como tema central el problema del "actuar humano", viejo tema de la filosofía práctica en la nomenos vieja distinción aristotélica. Nos proponemos, sin embargo, abordarlodesde dos perspectivas contemporáneas entre las que hemos encontrado notables puntos de convergencia que quisiera someter a discusión aquí conustedes: la fenomenología de la acción de H. Arendt y el análisis del lenguaje ordinario en la perspectiva de los "speech acts" de Austin y Searle.

  8. Perspectivas actuales del tratamiento endodóncico en dientes con lesiones periapicales crónicas

    OpenAIRE

    Canalda Sahli, Carlos

    1990-01-01

    Se analizan los aspectos histopatológicos de las lesiones periapiciales, el fenómeno de la proliferación epitelial intragranulomatosa como mecanismo patogénico de formación de cavidades quísticas microscópicas, los problemas diagnósticos de las mismas así como las perspectivas terapéuticas más actuales.

  9. Poder administrativo e intereses de satisfacción necesaria. Crisis y nuevas perspectivas del Derecho Administrativo

    OpenAIRE

    Rossi, Giampaolo

    2011-01-01

    En este trabajo se analizan, en primer lugar, las características más relevantes del poder administrativo y la tutela de intereses, en particular, de los intereses de satisfacción necesaria; en segundo lugar, la juridificación del poder, haciendo especial hincapié en el análises de esta cuestión en los Ordenamientos jurídicos anglosajones y chino; en tercer lugar, las nuevas perspectivas del Derecho Administrativo.

  10. Maskless localized patterning of biomolecules on carbon nanotube microarray functionalized by ultrafine atmospheric pressure plasma jet using biotin-avidin system

    Science.gov (United States)

    Abuzairi, Tomy; Okada, Mitsuru; Purnamaningsih, Retno Wigajatri; Poespawati, Nji Raden; Iwata, Futoshi; Nagatsu, Masaaki

    2016-07-01

    Ultrafine plasma jet is a promising technology with great potential for nano- or micro-scale surface modification. In this letter, we demonstrated the use of ultrafine atmospheric pressure plasma jet (APPJ) for patterning bio-immobilization on vertically aligned carbon nanotube (CNT) microarray platform without a physical mask. The biotin-avidin system was utilized to demonstrate localized biomolecule patterning on the biosensor devices. Using ±7.5 kV square-wave pulses, the optimum condition of plasma jet with He/NH3 gas mixture and 2.5 s treatment period has been obtained to functionalize CNTs. The functionalized CNTs were covalently linked to biotin, bovine serum albumin (BSA), and avidin-(fluorescein isothiocyanate) FITC, sequentially. BSA was necessary as a blocking agent to protect the untreated CNTs from avidin adsorption. The localized patterning results have been evaluated from avidin-FITC fluorescence signals analyzed using a fluorescence microscope. The patterning of biomolecules on the CNT microarray platform using ultrafine APPJ provides a means for potential application of microarray biosensors based on CNTs.

  11. Monte Carlo code for the damage of bio-molecules irradiated by x-ray free electron lasers. Incorporation of election impact ionization processes

    International Nuclear Information System (INIS)

    In this paper, electron impact ionization processes are incorporated in our Monte Carlo (MC) code for the calculation of the damage of the bio-molecules by the irradiation of x-ray free electron lasers (XFELs). The study of this damage is useful for the analysis of three-dimensional structure of the bio-molecules using x-ray free electron lasers because the damage appears as a noise for this analysis. The x-ray absorption and Compton scattering processes take place after the x-rays irradiate the target. Then, an electron is ionized from atoms and moves in the target. This electron also gives rise to an electron impact ionization process for the other atoms or ions. It is assumed that electron impact ionization processes occur only when the electrons cross a cross section, which is located at the place of the atomic nucleus and is perpendicular to the direction of the electron velocity. The x-ray flux, wavelength, and pulses of XFEL light pulses treated here are 1020-21/pulse/mm2, 10 fs, and 0.1 nm, respectively. We compare the frequencies of photo-electron impact ionization processes calculated by our MC code with those by rate equations. The relationship of these frequencies with shapes of targets using various ellipsoids as a target is discussed. (author)

  12. Palladium(II) complexes with highly basic imidazolin-2-imines and their reactivity toward small bio-molecules.

    Science.gov (United States)

    Bogojeski, Jovana; Volbeda, Jeroen; Freytag, Matthias; Tamm, Matthias; Bugarčić, Živadin D

    2015-10-21

    (DPENIm(iPr))Cl2] complex displays similar Pd-N distances of 2.034(4) and 2.038(3) Å. The studied systems are of interest because little is known about the substitution behavior of imidazolin-2-imine Pd(ii) complexes with bio-molecules under physiological conditions. PMID:26387638

  13. PERSPECTIVAS DEL PROCESO DE TITULACIÓN DE TIERRAS EN LA COMUNIDAD CAMPESINA SAN JUAN DE MIRAFLORES, 2011

    Directory of Open Access Journals (Sweden)

    Roger Ricardo Ríos Ramirez

    2014-12-01

    Full Text Available El objetivo del trabajo fue evaluar las perspectivas hacia la titulación de tierras en la Comunidad Campesina San Juan de Miraflores (CCSJM.El estudio fue de tipo descriptivo, con un diseño no experimental transversal. Se aplicó un cuestionario estructurado para evaluar perspectivas a una muestra de 353 comuneros seleccionados de manera aleatoria, estratificada y proporcional, previa validación de expertos y con una confiabilidad alfa de Cronbach α =  0.944.En la CCSJM, las parcelas no tienen las características necesarias para que la agricultura o ganadería se desarrollen, asimismo la actividad campesina no es la principal actividad económica. Asimismo, los comuneros de la CCSJM muestran una perspectiva favorable hacia la titulación de tierras.Por lo tanto, consideramos imperante el proceso de titulación de tierras y la promoción de opciones laborales distintas a las que usualmente realiza un campesino.

  14. La perspectiva de género: noema y nóesis de la epistemología feminista

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    Clara Eugenia Rojas Blanco

    2009-01-01

    Full Text Available En este artículo presento una reflexión en torno al potencial epistemológico de la perspectiva de género para abrir nuevos modos de conocer, comprender y escribir el mundo. Mi interés surge a partir de una (revisión o de un "volver a ver" los artículos publicados en Noésis de 1989 a 2008. Esta (revisión está formada por una perspectiva de género y por los enfoques de la epistemología feminista. Desde este punto de vista, es evidente la limitada participación de las académicas en general y la casi nula presencia de investigaciones y reflexiones con perspectiva de género. Argumento que en la actualidad esta borradura es injustificable desde un punto de vista de la epistemología posclásica o contemporánea.

  15. Claves para el Desarrollo del Plan de Convivencia en los Centros Educativos desde una Perspectiva Integral

    Directory of Open Access Journals (Sweden)

    Juan Carlos Torrego

    2014-02-01

    Full Text Available Este artículo muestra las principales conclusiones obtenidas en una investigación realizada en un centro de Educación Secundaria de Madrid (España. Su propósito ha sido conocer y comprobar cómo se están desarrollando en la práctica, los planteamientos que sobre convivencia se han realizado desde marcos de intervención global, como el que se propone en el Modelo Integrado (Torrego, 2006, 2008, así como identificar aspectos claves para el desarrollo de planes de convivencia en los centros educativos. Es una investigación cualitativa, realizada mediante un diseño de Estudio de Caso Único, donde se han combinado técnicas de análisis de documentos y datos, con la realización de entrevistas en profundidad a diversos miembros de la comunidad educativa. El interés del caso radica en que el centro trata la convivencia desde una perspectiva global, sobre la base del citado modelo integrado y en que destaca por los buenos resultados obtenidos en la mejora de la convivencia en los últimos años. Las conclusiones ponen de manifiesto la importancia de abordar la convivencia desde una perspectiva integral acorde con las características del contexto, que contemple aspectos curriculares, estructuras específicas para la mejora de la convivencia y que promueva la participación democrática de la comunidad educativa; además se evidencia la necesidad de una formación específica en convivencia, el papel central de la acción tutorial y de las metodologías cooperativas. Los aspectos detectados que precisan un mayor desarrollo son: la generalización de la formación en convivencia a todo el alumnado, la profundización en las medidas curriculares, la mejora de la acción tutorial y la generación de recursos adecuados para intervenir en los casos del alumnado con más dificultades.

  16. Educación permanente y continua en una perspectiva de integridad del ser

    Directory of Open Access Journals (Sweden)

    Izabel Cristina Feijó de Andrade

    2014-12-01

    Full Text Available Este artículo buscó discutir las articulaciones y distinciones entre los conceptos de educación permanente y educación continua de modo que favorezca la perspectiva de integridad del ser, vínculo que requiere saberes hasta entonces poco privilegiados en las Universidades y que demandan el rescate de dimensiones basadas en la experiencia, la didáctica y la existencia del educador, tanto individual, comportamental, cultural, social y espiritual. Consideramos que las nociones de educación permanente y educación continua poseen elementos entrelazables que nos permiten desarrollar la capacidad de reaccionar críticamente por medio de una relación autoformativa. Las revisiones teóricas implementadas permitieron algunas consideraciones sobre los procesos formativos actuales y las prácticas de profesores rumbo a una Educación para la Integridad. Concluimos provisoriamente que las aproximaciones y distinciones entre EP y EC pueden proporcionar a los profesores la toma de conciencia de su vinculación todo/parte y del sentido de la vida.

  17. Sistema NADPH oxidasa: nuevos retos y perspectivas = NADPH oxidase system: new challenges and perspectives

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    Arango Rincón, Julián Camilo

    2010-12-01

    Full Text Available El sistema NADPH oxidasa es un complejo multiproteico encargado de producir especies reactivas del oxígeno (ROS, por reactive oxygen species en diferentes células y tejidos. Es de gran importancia en las células fagocíticas (principalmente neutrófilos y macrófagos porque participa en la destrucción de microorganismos patógenos, mediante la fagocitosis y la formación de las trampas extracelulares de neutrófilos (NET, por neutrophils extracelular traps, así como en la activación de procesos inflamatorios. Las alteraciones en la producción de ROS por parte de las células fagocíticas a causa de defectos genéticos en los componentes del sistema generan la inmunodeficiencia primaria denominada enfermedad granulomatosa crónica (EGC. Este es un artículo de revisión sobre los componentes del sistema NADPH oxidasa, su distribución celular, mecanismo de activación y acción, así como de las funciones que desempeña en otros tejidos. Además, se revisan los defectos moleculares que llevan a la EGC y el tratamiento de esta, incluyendo la terapia con IFNγ, y finalmente las perspectivas para el estudio del sistema.

  18. Acupuntura en un servicio hospitalario en Argentina: experiencias y perspectivas de los usuarios

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    Betina Freidin

    2011-06-01

    Full Text Available Indagamos las experiencias y perspectivas de los usuarios de un servicio hospitalario público de acupuntura del noroeste argentino. Basamos el análisis en 18 entrevistas semi-estructuradas realizadas en el año 2005. Los entrevistados recurren a la acupuntura por dolencias crónicas, especialmente como paliativo del dolor, aunque varios extienden su uso para otros problemas de salud, frente a la ineficacia y/o efectos adversos de los tratamientos biomédicos, o para evitar cirugías menores. Incorporan la acupuntura a estrategias pluralistas de cuidado que junto con la biomedicina incluyen típicamente otras medicinas no convencionales. El contexto hospitalario facilita que prueben una medicina foránea. Varios usuarios encuentran el servicio de asesoramiento para "negociar" los tratamientos con sus médicos convencionales. Destacan la eficiencia organizativa del servicio y el compromiso de los médicos. Ante la demanda creciente de atención en un contexto de escasez de recursos advierten que ésta puede afectar la disponibilidad de turnos y la interacción médico-paciente.

  19. UNA PERSPECTIVA HETERODOXA SUGERIDA PARA EL ESTUDIO DE LAS EMPRESAS FAMILIARES EN COLOMBIA

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    RUTH ESPERANZA ROMÁN CASTILLO

    2009-01-01

    Full Text Available A partir de la revisión de fuentes secundarias en forma de libros, artículos y trabajos de grado, y con propósitos de reflexión y evaluación, en este artículo se identifican algunas tendencias ortodoxas de la investigación nacional sobre las empresas familiares, y un grupo de perspectivas heterodoxas señaladas por investigadores del mundo anglosajón. Los resultados de la revisión permiten concluir la alta difusión de las teorías ortodoxas entre investigadores y estudiantes; mientras que, los enfoques heterodoxos son menos conocidos y aplicados. El estudio profundo de este grupo de teorías y constructos más recientes y la evaluación de su aplicabilidad para comprender la idiosincrasia de las empresas familiares colombianas, se propone como una corriente alternativa de investigación nacional.

  20. Derechos humanos y emociones desde una perspectiva de los colonizados: Antropofagia, Surrealismo Legal y Estudios Subalternos

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    José Manuel Barreto

    2014-12-01

    Full Text Available El Tercer Mundo puede experimentar fácilmente una existencia fantasmal: hablamos pero no somos oídos. No obstante, en nuestra cultura hay numerosas tendencias y posiciones que son relevantes para la tarea de pensar a los derechos humanos desde una perspectiva distinta. Entre ellos, las críticas al racionalismo desarrolladas por Oswald de Andrade y Luis Alberto Warat en Brasil y Argentina –en las que existe la posibilidad de integrar las emociones en la teoría de los derechos humanos. Compartiendo la preocupación por aquellos excluidos del “orden mundial” y el llamado a la sensibilidad, los Estudios Subalternos desarrollaron ideas que apunta a establecer una relación entre colonialismo, derechos humanos y sufrimiento. Este es el caso del trabajo de Upendra Baxi, quien ha realizado una crítica a lasteorías occidentales del derecho y ha elaborado un encuentro fructífero entre los aportes de los Estudios Subalternos y la teoría de los derechos humanos.