WorldWideScience

Sample records for research semester sers

  1. SERS internship fall 1995 abstracts and research papers

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Beverly

    1996-05-01

    This report is a compilation of twenty abstracts and their corresponding full papers of research projects done under the US Department of Energy Science and Engineering Research Semester (SERS) program. Papers cover a broad range of topics, for example, environmental transport, supercomputers, databases, biology. Selected papers were indexed separately for inclusion the the Energy Science and Technology Database.

  2. SERS internship: Spring 1994 abstracts and research papers

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, B.

    1994-05-06

    This document contains abstracts from the science and engineering research semester from the Lawrence Livermore National Laboratory. Projects cover many areas in the fields of contaminant removal from the environment, physics, and genetics research. Individual projects were processed separately for the Department of Energy databases.

  3. Bringing research into a first semester organic chemistry laboratory with the multistep synthesis of carbohydrate-based HIV inhibitor mimics.

    Science.gov (United States)

    Pontrello, Jason K

    2015-01-01

    Benefits of incorporating research experiences into laboratory courses have been well documented, yet examples of research projects designed for the first semester introductory organic chemistry lab course are extremely rare. To address this deficiency, a Carbohydrate-Based human immunodeficiency virus (HIV) Inhibitor project consisting of a synthetic scheme of four reactions was developed for and implemented in the first semester organic lab. Students carried out the synthetic reactions during the last 6 of 10 total labs in the course, generating carbohydrate-based dimeric target molecules modeled after published dimers with application in HIV therapy. The project was designed to provide a research experience through use of literature procedures for reactions performed, exploration of variation in linker length in the target structure, and synthesis of compounds not previously reported in the scientific literature. Project assessment revealed strong student support, indicating enhanced engagement and interest in the course as a direct result of the use of scientific literature and the applications of the synthesized carbohydrate-based molecules. Regardless of discussed challenges in designing a research project for the first semester lab course, the finding from data analysis that a project implemented in the first semester lab had significantly greater student impact than a second semester project should provide motivation for development of additional research projects for a first semester organic course. © 2015 The International Union of Biochemistry and Molecular Biology.

  4. Experimental research on thermal comfort in the university classroom of regular semesters in Korea

    International Nuclear Information System (INIS)

    Jung, Gun Joo; Oh, Geun Sug; Im, Young Bin; Song, Sung Ki; Ahn, Young Chull

    2011-01-01

    This research has investigated physical variables affecting indoor thermal comfort and subjective responses of thermal comfort of students in a university in Korea in which the weather is oceanic temperate climate, and has been performed to contribute to the research fields of Sustainable Thermal Standard and Adaptive Thermal Comfort (ATC). This research is based on the ISO 7730-2005 standard and the ATC theories and 4 main variables of PMV such as dry bulb temperature (Ta), relative humidity (RH), black bulb temperature (Tg), and air velocity (Va) are measured once a week during two regular semesters. A clothing insulation, a thermal sensation vote (TSV), an acceptability of thermal environment, and a preference for cooling and heating are investigated at the same time using a questionnaire. This study was carried out for 26 weeks during the spring season, from March to June 2009, and the autumn season, from September to December 2009. The main achievements of this study are as follows. Monthly Mean Outdoor Temperature (MMOT) and Operative Temperature (OT) in the classroom during research periods are 7.4∼23.3 .deg. C and 17.5∼29.0 .deg. C, respectively. The acceptability ratio of thermal environment shows over 80% when the range of OT in the classroom is 17∼25 .deg. C, and the range can be applicable to operative index of heating and cooling of classroom. The mean TSV of respondents is almost 'neutral (0)' when the PMV in the classroom moves to 'neutral (0)' and 'slightly cool (-1)', and the TSV is almost '+1.5' when the PMV moves to 'slightly warm (+1)'. The acceptability ratio of thermal environment is slightly different from ASHRAE Standard 55-2004. So it is necessary to more investigate standard range of acceptability of thermal environment in oceanic temperate climate region using much more databases

  5. Experimental research on thermal comfort in the university classroom of regular semesters in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Gun Joo; Oh, Geun Sug; Im, Young Bin [Pukyong National University, Busan (Korea, Republic of); Song, Sung Ki [Hiroshima Institute of Technology, Hiroshima (Japan); Ahn, Young Chull [Pusan National University, Busan (Korea, Republic of)

    2011-02-15

    This research has investigated physical variables affecting indoor thermal comfort and subjective responses of thermal comfort of students in a university in Korea in which the weather is oceanic temperate climate, and has been performed to contribute to the research fields of Sustainable Thermal Standard and Adaptive Thermal Comfort (ATC). This research is based on the ISO 7730-2005 standard and the ATC theories and 4 main variables of PMV such as dry bulb temperature (Ta), relative humidity (RH), black bulb temperature (Tg), and air velocity (Va) are measured once a week during two regular semesters. A clothing insulation, a thermal sensation vote (TSV), an acceptability of thermal environment, and a preference for cooling and heating are investigated at the same time using a questionnaire. This study was carried out for 26 weeks during the spring season, from March to June 2009, and the autumn season, from September to December 2009. The main achievements of this study are as follows. Monthly Mean Outdoor Temperature (MMOT) and Operative Temperature (OT) in the classroom during research periods are 7.4{approx}23.3 .deg. C and 17.5{approx}29.0 .deg. C, respectively. The acceptability ratio of thermal environment shows over 80% when the range of OT in the classroom is 17{approx}25 .deg. C, and the range can be applicable to operative index of heating and cooling of classroom. The mean TSV of respondents is almost 'neutral (0)' when the PMV in the classroom moves to 'neutral (0)' and 'slightly cool (-1)', and the TSV is almost '+1.5' when the PMV moves to 'slightly warm (+1)'. The acceptability ratio of thermal environment is slightly different from ASHRAE Standard 55-2004. So it is necessary to more investigate standard range of acceptability of thermal environment in oceanic temperate climate region using much more databases.

  6. SERS internship: Fall 1994 abstracts and research papers

    International Nuclear Information System (INIS)

    Goldman, B.

    1994-12-01

    This publication is a collection of articles generated as a result of the fall 1994 Science and Engineering Research Semester program at Lawrence Livermore Laboratory. Research titles include: electrochemical cells in the reduction of hexavalent chromium; an automated system for studying the power distribution of electron beams; the mapping of novel genes to human chromosome 19; bolometer analysis comparisons; design and implementation of the LLNL Gigabit Testbed; in vitro synthesis and purification of PhIP-Deoxyguanosine and PhIP-DNA Covalent Complexes; pre-thymic somatic mutation leads to high mutant frequency hypoxanthine-guanine phosphoribosyl transferase gene; characterization of thin film multi-layers with magnetization curves and modeling of low angle X-ray diffraction data; total least squares; determining the water content of the Geysers Graywacke of northern California; a general approach to sharing data between scientific representations; nanomechanical properties of SiC thin films grown from C 60 precursors; advanced information technology, a tool set for building clean database applications; the design of an automated electrolytic enrichment procedure for tritium; fluvial terrace dating using in-situ cosmogenic 21 Ne; computer- aided mapping of stream channels beneath the Lawrence Livermore National Laboratory, Livermore, CA; X-ray spectroscopic technique for energetic electron transport studies in short-pulse laser/plasma interactions. Separate entries have been put in the energy data base for articles from this report. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database

  7. SERS internship: Fall 1994 abstracts and research papers

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, B.

    1994-12-01

    This publication is a collection of articles generated as a result of the fall 1994 Science and Engineering Research Semester program at Lawrence Livermore Laboratory. Research titles include: electrochemical cells in the reduction of hexavalent chromium; an automated system for studying the power distribution of electron beams; the mapping of novel genes to human chromosome 19; bolometer analysis comparisons; design and implementation of the LLNL Gigabit Testbed; in vitro synthesis and purification of PhIP-Deoxyguanosine and PhIP-DNA Covalent Complexes; pre-thymic somatic mutation leads to high mutant frequency hypoxanthine-guanine phosphoribosyl transferase gene; characterization of thin film multi-layers with magnetization curves and modeling of low angle X-ray diffraction data; total least squares; determining the water content of the Geysers Graywacke of northern California; a general approach to sharing data between scientific representations; nanomechanical properties of SiC thin films grown from C{sub 60} precursors; advanced information technology, a tool set for building clean database applications; the design of an automated electrolytic enrichment procedure for tritium; fluvial terrace dating using in-situ cosmogenic {sup 21}Ne; computer- aided mapping of stream channels beneath the Lawrence Livermore National Laboratory, Livermore, CA; X-ray spectroscopic technique for energetic electron transport studies in short-pulse laser/plasma interactions. Separate entries have been put in the energy data base for articles from this report. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  8. SERS internship Fall 1992--Spring 1993: Abstract and research papers

    Energy Technology Data Exchange (ETDEWEB)

    1993-08-05

    This report contains the abstracts and research papers by students on a variety of topics in engineering, genetics, solid state physics, thermonuclear energy, astrophysics, and other science related topics.

  9. SERS internship Fall 1992--Spring 1993: Abstract and research papers

    International Nuclear Information System (INIS)

    1993-01-01

    This report contains the abstracts and research papers by students on a variety of topics in engineering, genetics, solid state physics, thermonuclear energy, astrophysics, and other science related topics

  10. Stakeholders' Perspectives on Stakeholder-engaged Research (SER): Strategies to Operationalize Patient-centered Outcomes Research Principles for SER.

    Science.gov (United States)

    Mackie, Thomas I; Sheldrick, Radley C; de Ferranti, Sarah D; Saunders, Tully; Rojas, Erick G; Leslie, Laurel K

    2017-01-01

    US federal funding agencies increasingly incentivize stakeholder-engaged research which represents a paradigm shift toward incorporating a range of stakeholders in research design, conduct, and dissemination. We use qualitative methods to capture experience-based recommendations on how to operationalize 4 Patient-Centered Outcomes Research (PCOR) principles in stakeholder-engaged research, specifically: (1) reciprocal relationships; (2) colearning; (3) partnership; and (4) trust, transparency, and honesty. We conducted semistructured interviews with members of a stakeholder panel who participated in a 2-year comparative effectiveness study of cholesterol screening and treatment among young adults. Participants included 8 young adults and parent panelists and 11 professional panelists (clinicians, researchers, policy developers, and disseminators). The interview guide included questions about the 4 PCOR principles and queried preferred strategies to attain them. Interview transcripts were analyzed using an a priori and emergent coding structure. Participants provided strategies to promote the 4 PCOR principles. Although some stakeholder-identified strategies were complementary, others conflicted due to (1) competing ideologies identified among the principles, and (2) distinct stakeholder preferences. Illustrative of competing ideologies, participants simultaneously preferred receiving relevant articles before calls (to facilitate colearning) but also minimal outside reading (to achieve partnership). Illustrative of distinct stakeholder preferences, young adult and parent panelists generally preferred calls to occur on weekends/evenings, whereas professional panelists preferred mid-week work hours. Our exploratory study provides stakeholder-identified strategies to achieve the 4 PCOR principles, and demonstrates the need to identify, acknowledge, and address potentially conflicting strategies due to the potential for competing ideologies or variation in stakeholder

  11. Fabrication and Characterization of the US Army Research Laboratory Surface Enhanced Raman Scattering (SERS) Substrates

    Science.gov (United States)

    2017-12-04

    environmental contamination concerns. For SERS to function as an accurate, reliable, and reproducible technology for all of these research areas, it is... manufactured , demonstrate signal reproducibility from substrate to substrate and lot to lot, and are capable of being used in a host of environments...support staff must have safe food , air, water, and a secure environment. To ensure this safety it is important to not only detect, but also to

  12. [AgBr colloids prepared by electrolysis and their SERS activity research].

    Science.gov (United States)

    Si, Min-Zhen; Fang, Yan; Dong, Gang; Zhang, Peng-Xiang

    2008-01-01

    Ivory-white AgBr colloids were prepared by means of electrolysis. Two silver rods 1.0 cm in diameter and 10.0 cm long were respectively used as the negative and positive electrodes, the aqueous solution of hexadecyl trimethyl ammonium bromide was used as the electrolyte, and a 7 V direct current was applied on the silver rods for three hours. The obtained AgBr colloids were characterized by UV-Vis spectroscopy, transmission electron microscopy, and SERS using a 514. 5 nm laser line on Renishaw 2000 Raman spectrometer. These particles are about nanometer size and their shapes are as spherical or elliptic, with a slight degree of particle aggregation. The UV-Vis spectra exhibit a large plasmon resonance band at about 292.5 nm, similar to that reported in the literature. The AgBr colloids were very stable at room temperature for months. In order to test if these AgBr colloids can be used for SERS research, methyl orange, Sudan red and pyridine were used. It was found that AgBr colloids have SERS activity to these three molicules. For methyl orange, the intense Raman peaks are at 1 123, 1 146, 1 392, 1 448 and 1 594 cm(-1); for Sudan red, the intense Raman peaks are at 1 141, 1 179, 1 433 and 1 590 cm(-1); and for pyridine, the intense Raman peaks are at 1 003, 1 034 and 1 121 cm(-1). It is noticeable that SERS of methyl orange was observed on AgBr colloids, but not on the gray and yellow silver colloids prepared by traditional means. The possible reason was explained. One major advantage of this means is the absence of the spectral interference such as citrate, BH4- arising from reaction products of the colloids formation process. On AgBr colloids, one can get some molecular SERS impossible to get on the gray and yellow silver colloids.

  13. Using a Molecular-Genetic Approach to Investigate Bacterial Physiology in a Continuous, Research-Based, Semester-Long Laboratory for Undergraduates

    Directory of Open Access Journals (Sweden)

    Jeremiah Foster Ault

    2011-09-01

    Full Text Available Designing investigative laboratory exercises that encourage critical thinking, problem solving, and independent thought for upper-division biology courses is a difficult but worthwhile task. In an effort to do so, we developed a semester-long, continuous, research-based investigative laboratory that integrates numerous genetic and molecular biology methods into the investigation of a bacterial physiological process. In this lab, students use random Tn5 transposon mutagenesis to create prodigiosin pigment mutants in the bacterium, Serratia marcescens. This is followed by phenotypic characterization, cloning, and sequencing the Tn insertion site to identify genes involved in pigment biosynthesis. During this lab, students gain ample experience performing basic lab techniques while learning about — and applying — methods for elucidating gene function. The approach to the laboratory and the outcomes are intimately integrated into the teaching of many fundamental physiological processes underlying prodigiosin production in bacteria. The result is a cohesive course that integrates the theory and application of molecular genetic techniques with the study of bacterial physiology. Assessments of student learning objectives demonstrated that students greatly improved their understanding of both physiological processes and the genetic techniques used to investigate them. In addition, students felt that this semester-long exercise provided the necessary laboratory experience they needed and desired in preparation for careers in molecular biology, microbiology, and biochemistry.

  14. D.R.F. - Grenoble Department of Fundamental Research. Semi-annual bulletin Nr 2, 1972 2. semester

    International Nuclear Information System (INIS)

    Blachot, J.; Carraz, L.C.; Ferrieu, A.; Monnand, E.; Brissot, R.; Crancon, J.; Ristori, C.; Schussler, F.; Moussa, A.; Desreumaux, S.; Chisolm, A.; Perrin, P.; Bouchez, R.; Lagrange, R.; Casali, G.; Moser, P.; Verdone, J.; Boissier, M.; Ligeon, E.; Soulie, J.C.; Minier, C.; Lauzier, J.; Charles, M.; Cox, R.T.; Herve, A.; Picard, R.; Rius, G.; Santier, C.; Gloux, J.; Gaillard, J.; Lamotte, B.; Rechenberg, H.; Billard, L.; Chamberod, A.; Natta, M.; Chamard-Bois, R.; Buisson, G.; Fournier, J.M.; Blaise, A.; Belakhovski, M.; Boucher, J.P.; Nechtschein, M.; Marticorena, B.; Nechtschein, M.; Kervennal, J.; Ligeon, E.; Bruel, M.; Pautrat, J.L.; Bontemps, A.; Barruel, F.; Lissalde, F.C.; Peuzin, J.C.; Tissier, A.; Boyer, P.; Baudry, A.; Hombrouck, J.; Rey, P.; Decorps, M.; Genoud, F.; Schouler, M.C.; Colbeau, A.; Vignais, P.M.; Piette, L.H.; Albrand, J.P.; Cogne, A.; Gagnaire, D.; Martin, J.; Robert, J.B.; Briere, R.; Vignon, M.; Vottero, P.; Ellinger, Y.; Subra, R.; Rassat, A.; Cauquis, G.; Serve, D.; Genies, M.; Ayant, Y.; Belorizki, E.; Gagnaire, D.; Taieb, M.; Hudry-Clergeon, G.; Paturel, L.; Suscillon, M.; Dognin, J.; Girardet, J.L.; Mouriquand, J.; Gorka, C.; Satre, M.; Lunardi, J.; Vignais, P.V.; Huet, J.; Andre, J.; Vignais, P.M.; Colomb, M.G.; Cheruy, Ariette; Polverelli, M.; Teoule, R.; Gilet, R.; Gagnaire, J.; Laffon, J.L.; Servoz-Gavin, P.; Lachet, B.; Constantinescu, O.; Hoffstein, V.; RAY, D.K.; Saint-Paul, M.; Chambert, G.; Ribeiro, C.A.

    1973-01-01

    This document gathers several study reports in the field of fundamental research. The first part contains studies which more particularly addressed nuclear physics: study of fission and fission products by fission product distribution measurement and nuclear spectroscopy, study of light nuclei by fast neutrons, study of the neutron electric dipolar moment). The second part concerns condensed matter physics: defects and effects of radiations in solids (pure metals, alloys, semiconductors, ionic crystals, molecular crystals or ferro-electric crystals with hydrogen bond), magnetism (study of magnetic properties of different materials such as transition element compounds and alloys, rare earth compounds and alloys, and actinides; studies of other magnetism-related issues: two-dimensional magnetic order, magnetic wall structure, critical phenomenon and phase transformation, crystalline field in refractory metals, influence of conduction electrons, free-radicals in solid phase; crystal structure and properties of transition element compounds, alloys and complexes; studies of semiconductor properties and behaviour). The third part deals with physical chemistry and biophysics: studies of steady free radicals, use of free-radical spin markers in biology, stereochemistry and conformation studies, studies of vegetal macromolecules, theoretical chemistry, chemically-induced nuclear polarisation, organic and analytic electrochemistry, studies of organic photochemistry, proton dynamics in the hydrogen bond, studies of molecular movement, studies of polymers. The fourth part concerns biology: protein structure and functions, biological membrane structure and functions, radiobiology, vegetal physiology, medical research. The last chapters address advanced techniques, general services (electronic paramagnetic resonance) and applied research (pollution study: purification kinetics of river water in its torrential regime)

  15. ROUNTABLE AS A TECHNIQUE IN TEACHING WRITING A NARRATIVE TEXT: A QUALITATIVE RESEARCH ON THE FOURTH SEMESTER STUDENTS OF THE ENGLISH EDUCATION DEPARTMENT OF IKIP PGRI SEMARANG

    Directory of Open Access Journals (Sweden)

    Siti Musarokah

    2017-04-01

    Full Text Available This study mainly aims at applying Roundtable technique in teaching writing narrative text for the fourth semester students of English Education Department of IKIP PGRI Semarang in the academic year 2012-2013. This study also aims at finding out the problems faced by the students and the lecturer when the technique is applied in teaching learning process. The design of this study is a qualitative research. Observation and interview were used to collect the data. In analyzing the data, there are three steps done, namely data reduction, data display, and drawing conclusion. The result of the study is that to apply Roundtable technique in teaching narrative text, there are some steps done: 1 the students were grouped into six each of which consisted of 5 to 6 students, 2 the groups were given the same topic, 3 the lecturer gave a paper and a pen to each group, 4 roles were labeled to each student based on the generic structure of narrative text, 5 students in each group wrote narrative text based on the roles got, 6 each group submitted their work, 7 each group evaluated and corrected the other group’s work, and 8 each group reported their group evaluation to the whole class. There were some problems faced by the students when the technique applied: 1 the students seemed to face difficulty when they had to continue their friend’s work, and 2 the students tend to ask their friends in individual work because of their lack of vocabulary mastery, 3 chaos happened in some groups due to different perspective they had toward the story. Instead of the problems faced by the students, the lecturer also faced the difficulties in running this technique: 1 the lecturer got involved to deep in the group management and 2 the lecturer found it difficult in giving guidance to the students.

  16. Student related determinants of the first semester academic status ...

    African Journals Online (AJOL)

    Student related determinants of the first semester academic status: the case of 2006/7 first year students at some selected faculties of Jimma university. ... This research, therefore, attempted to unfold the magnitude of academic failure and students related factors predicting academic failure in the first semester of 2006/ 07 ...

  17. ABOUT PROBABILITY OF RESEARCH OF THE NN Ser SPECTRUM BY MODEL ATMOSPHERES METHOD

    OpenAIRE

    Sakhibullin, N. A.; Shimansky, V. V.

    2017-01-01

    The spectrum of close binary system NN Ser is investigated by a models atmospheres method. It is show that the atmosphere near the centrum of a hot spot on surface of red dwarf has powerful chromospheres, arising from heating in Laiman continua. Four models of binary system with various of parameters are constructed and their theoretical spectra are obtained. Temperature of white dwarf Tef = 62000 K, radius of the red dwarf RT = 0.20139 and angle inclination of system i = 82“ are determined. ...

  18. Motivation of first semester undergraduate students

    DEFF Research Database (Denmark)

    Schlichter, Bjarne; Sigvardsen, Kari; Jonsson, Sofia

    in the curriculum. Method - The study is based on interpretative research (Walsham, 2006; Yin, 2003) and the method chosen was a qualitative case study (Myers, 2009). The data for this study was collected through fieldwork and semi-structured interviews. The fieldwork was conducted during the autumn semester 2010...... of first semester undergraduate students. Keywords -Motivation; first year undergraduate students; Management Information Systems; teaching assistants. Paper type - Research paper....... to the processes in a company. 2) Methods for formal modeling of processes, data and occurrences. 3) An introduction to a company's information systems and the relationship of these to business strategies. In addition to the lectures and tutorials, the students have to hand in a prescribed group assignment...

  19. Bringing the excitement and motivation of research to students; Using inquiry and research-based learning in a year-long biochemistry laboratory : Part II-research-based laboratory-a semester-long research approach using malate dehydrogenase as a research model.

    Science.gov (United States)

    Knutson, Kristopher; Smith, Jennifer; Nichols, Paul; Wallert, Mark A; Provost, Joseph J

    2010-09-01

    Research-based learning in a teaching environment is an effective way to help bring the excitement and experience of independent bench research to a large number of students. The program described here is the second of a two-semester biochemistry laboratory series. Here, students are empowered to design, execute and analyze their own experiments for the entire semester. This style of laboratory replaces a variety of shorter labs in favor of an in depth research-based learning experience. The concept is to allow students to function in independent research groups. The research projects are focused on a series of wild-type and mutant clones of malate dehydrogenase. A common research theme for the laboratory helps instructors administer the course and is key to delivering a research opportunity to a large number of students. The outcome of this research-based learning laboratory results in students who are much more confident and skilled in critical areas in biochemistry and molecular biology. Students with research experience have significantly higher confidence and motivation than those students without a previous research experience. We have also found that all students performed better in advanced courses and in the workplace. Copyright © 2010 International Union of Biochemistry and Molecular Biology, Inc.

  20. Some participants may be better than others: sustained attention and motivation are higher early in semester.

    Science.gov (United States)

    Nicholls, Michael E R; Loveless, Kellie M; Thomas, Nicole A; Loetscher, Tobias; Churches, Owen

    2015-01-01

    Many studies use multiexperiment designs where experiments are carried out at different times of semester. When comparing between experiments, the data may be confounded by between-participants effects related to motivation. Research indicates that course-credit participants who engage in research early in semester have different personality and performance characteristics compared to those tested late in semester. This study examined whether the semester effect is caused by internal (inherent motivation of the participant) or external (looming exams, essays) factors. To do this, sustained attention and intrinsic/extrinsic motivation was measured in groups of course-credit (n = 40) and paid (n = 40) participants early and late in semester. While there was no difference in sustained attention between the groups early in semester, the course-credit group performed significantly worse late in semester. The course-credit group also showed a significant decrease in intrinsic motivation with time whereas the paid participants showed no change. Because changes were not seen for both groups, the semester difference cannot be due to external factors. Instead, the data demonstrate that course-credit participants who engage early have high sustained attention and intrinsic motivation compared to their late counterparts, who leave their participation to the last minute. Researchers who use multiexperimental designs across semester need to control for these effects--perhaps by using paid participants who do not vary across semester.

  1. Ser reina

    Directory of Open Access Journals (Sweden)

    José Manuel NIETO SORIA

    2006-07-01

    Full Text Available L’historiographie du règne des Rois Catholiques, héritière directe de celle des autres Trastamare, se caractérise par son étroite relation avec des enjeux politiques concrets. L’activité historiographie s’est ainsi inscrite elle-même dans le cadre des conflits politiques en cours. C’est pourquoi la royauté d’Isabelle Ire de Castille impliqua une bonne part de la production historiographique de cettte époque : soit qu’on dénonçât un déficit de légitimité dû à sa condition féminine, soit qu’on démentît, au contraire, ce déficit en attribuant à la reine des qualités « masculines ». Bien entendu, ces débats furent fonction de l’engagement politique de chacun des historiens.La cronística y la historiografía del reinado de los Reyes Católicos, como directas herederas de la labor historiográfica de la época de los monarcas Trastámara, se caracterizó por su estrecha vinculación con intereses políticos concretos, inscribiéndose la propia actividad historiográfica en el marco de los conflictos políticos en curso. Por ello, la dimensión regia de Isabel I de Castilla supuso una dimensión significativa del quehacer historiográfico de la época, bien para plantear un déficit de legitimidad por razón de su propia condición femenina, bien para negar tal déficit con la atribución de “cualidades masculinas” en su persona. De este modo, la toma en consideración del hecho de “ser reina” representó una dimensión significativa del quehacer historiográfico, de acuerdo siempre con los compromisos políticos de los distintos historiadores de la época.

  2. The Impact of an Interactive Statistics Module on Novices' Development of Scientific Process Skills and Attitudes in a First-Semester Research Foundations Course.

    Science.gov (United States)

    Marsan, Lynnsay A; D'Arcy, Christina E; Olimpo, Jeffrey T

    2016-12-01

    Evidence suggests that incorporating quantitative reasoning exercises into existent curricular frameworks within the science, technology, engineering, and mathematics (STEM) disciplines is essential for novices' development of conceptual understanding and process skills in these domains. Despite this being the case, such studies acknowledge that students often experience difficulty in applying mathematics in the context of scientific problems. To address this concern, the present study sought to explore the impact of active demonstrations and critical reading exercises on novices' comprehension of basic statistical concepts, including hypothesis testing, experimental design, and interpretation of research findings. Students first engaged in a highly interactive height activity that served to intuitively illustrate normal distribution, mean, standard deviation, and sample selection criteria. To enforce practical applications of standard deviation and p -value, student teams were subsequently assigned a figure from a peer-reviewed primary research article and instructed to evaluate the trustworthiness of the data. At the conclusion of this exercise, students presented their evaluations to the class for open discussion and commentary. Quantitative assessment of pre- and post-module survey data indicated a statistically significant increase both in students' scientific reasoning and process skills and in their self-reported confidence in understanding the statistical concepts presented in the module. Furthermore, data indicated that the majority of students (>85%) found the module both interesting and helpful in nature. Future studies will seek to develop additional, novel exercises within this area and to evaluate the impact of such modules across a variety of STEM and non-STEM contexts.

  3. The Impact of an Interactive Statistics Module on Novices’ Development of Scientific Process Skills and Attitudes in a First-Semester Research Foundations Course

    Directory of Open Access Journals (Sweden)

    Lynnsay A. Marsan

    2016-12-01

    Full Text Available Evidence suggests that incorporating quantitative reasoning exercises into existent curricular frameworks within the science, technology, engineering, and mathematics (STEM disciplines is essential for novices’ development of conceptual understanding and process skills in these domains. Despite this being the case, such studies acknowledge that students often experience difficulty in applying mathematics in the context of scientific problems. To address this concern, the present study sought to explore the impact of active demonstrations and critical reading exercises on novices’ comprehension of basic statistical concepts, including hypothesis testing, experimental design, and interpretation of research findings. Students first engaged in a highly interactive height activity that served to intuitively illustrate normal distribution, mean, standard deviation, and sample selection criteria. To enforce practical applications of standard deviation and p-value, student teams were subsequently assigned a figure from a peer-reviewed primary research article and instructed to evaluate the trustworthiness of the data. At the conclusion of this exercise, students presented their evaluations to the class for open discussion and commentary. Quantitative assessment of pre- and post-module survey data indicated a statistically significant increase both in students’ scientific reasoning and process skills and in their self-reported confidence in understanding the statistical concepts presented in the module. Furthermore, data indicated that the majority of students (>85% found the module both interesting and helpful in nature. Future studies will seek to develop additional, novel exercises within this area and to evaluate the impact of such modules across a variety of STEM and non-STEM contexts.

  4. Many Labs 3 : Evaluating participant pool quality across the academic semester via replication

    NARCIS (Netherlands)

    Ebersole, Charles R.; Atherton, Olivia E.; Belanger, Aimee L.; Skulborstad, Hayley M.; Allen, Jill M.; Banks, Jonathan B.; Baranski, Erica; Bernstein, Michael J.; Bonfiglio, Diane B. V.; Boucher, Leanne; Brown, Elizabeth R.; Budiman, Nancy I.; Cairo, Athena H.; Capaldi, Colin A.; Chartier, Christopher R.; Chung, J.M.H.; Cicero, David C.; Coleman, Jennifer A.; Conway, John G.; Davis, William E.; Devos, Thierry; Fletcher, Melody M.; German, Komi; Grahe, Jon E.; Hermann, Anthony D.; Hicks, Joshua A.; Honeycutt, Nathan; Humphrey, Brandon; Janus, Matthew; Johnson, David J.; Joy-Gaba, Jennifer A.; Juzeler, Hannah; Keres, Ashley; Kinney, Diana; Kirshenbaum, Jacqeline; Klein, Richard A.; Lucas, Richard E.; Lustgraaf, Christopher J. N.; Martin, Daniel; Menon, Madhavi; Metzger, Mitchell; Moloney, Jaclyn M.; Morse, Patrick J.; Prislin, Radmila; Razza, Timothy; Re, Daniel E.; Rule, Nicholas O.; Sacco, Tdonald F.; Sauerberger, Kyle; Shrider, Emily; Shultz, Megan; Siemsen, Courtney; Sobocko, Karin; Sternglanz, R. Weylin; Summerville, Amy; Tskhay, Konstantin O.; van Allen, Zack; Vaughn, Leigh Ann; Walker, Ryan J.; Weinberg, Ashley; Wilson, John Paul; Wirth, James H.; Wortman, Jessica; Nosek, Brian A.

    2016-01-01

    The university participant pool is a key resource for behavioral research, and data quality is believed to vary over the course of the academic semester. This crowdsourced project examined time of semester variation in 10 known effects, 10 individual differences, and 3 data quality indicators over

  5. Lecture Notes in Statistics. 3rd Semester

    DEFF Research Database (Denmark)

    The lecture note is prepared to meet the requirements for the 3rd semester course in statistics at the Aarhus School of Business. It focuses on multiple regression models, analysis of variance, and log-linear models.......The lecture note is prepared to meet the requirements for the 3rd semester course in statistics at the Aarhus School of Business. It focuses on multiple regression models, analysis of variance, and log-linear models....

  6. Toward practical SERS sensing

    Science.gov (United States)

    Zhao, Yiping

    2012-06-01

    Since its discovery more than 30 years ago, surface-enhanced Raman scattering (SERS) has been recognized as a highly sensitive detection technique for chemical and biological sensing and medical diagnostics. However, the practical application of this remarkably sensitive technique has not been widely accepted as a viable diagnostic method due to the difficulty in preparing robust and reproducible substrates that provide maximum SERS enhancement. Here, we demonstrate that the aligned silver nanorod (AgNR) array substrates engineered by the oblique angle deposition method are capable of providing extremely high SERS enhancement factors (>108). The substrates are large area, uniform, reproducible, and compatible with general microfabrication process. The enhancement factor depends strongly on the length and shape of the Ag nanorods and the underlying substrate coating. By optimizing AgNR SERS substrates, we show that SERS is able to detect trace amount of toxins, virus, bacteria, or other chemical and biological molecules, and distinguish different viruses/bacteria and virus/bacteria strains. The substrate can be tailored into a multi-well chip for high throughput screening, integrated into fiber tip for portable sensing, incorporated into fluid/microfluidic devices for in situ real-time monitoring, fabricated onto a flexible substrate for tracking and identification, or used as on-chip separation device for ultra-thin layer chromatography and diagnostics. By combining the unique SERS substrates with a handheld Raman system, it can become a practical and portable sensor system for field applications. All these developments have demonstrated that AgNR SERS substrates could play an important role in the future for practical clinical, industrial, defense, and security sensing applications.

  7. Achieving optimal SERS through enhanced experimental design.

    Science.gov (United States)

    Fisk, Heidi; Westley, Chloe; Turner, Nicholas J; Goodacre, Royston

    2016-01-01

    One of the current limitations surrounding surface-enhanced Raman scattering (SERS) is the perceived lack of reproducibility. SERS is indeed challenging, and for analyte detection, it is vital that the analyte interacts with the metal surface. However, as this is analyte dependent, there is not a single set of SERS conditions that are universal. This means that experimental optimisation for optimum SERS response is vital. Most researchers optimise one factor at a time, where a single parameter is altered first before going onto optimise the next. This is a very inefficient way of searching the experimental landscape. In this review, we explore the use of more powerful multivariate approaches to SERS experimental optimisation based on design of experiments and evolutionary computational methods. We particularly focus on colloidal-based SERS rather than thin film preparations as a result of their popularity. © 2015 The Authors. Journal of Raman Spectroscopy published by John Wiley & Sons, Ltd.

  8. A semester-long project-oriented biochemistry laboratory based on Helicobacter pylori urease.

    Science.gov (United States)

    Farnham, Kate R; Dube, Danielle H

    2015-01-01

    Here we present the development of a 13 week project-oriented biochemistry laboratory designed to introduce students to foundational biochemical techniques and then enable students to perform original research projects once they have mastered these techniques. In particular, we describe a semester-long laboratory that focuses on a biomedically relevant enzyme--Helicobacter pylori (Hp) urease--the activity of which is absolutely required for the gastric pathogen Hp to colonize the human stomach. Over the course of the semester, students undertake a biochemical purification of Hp urease, assess the success of their purification, and investigate the activity of their purified enzyme. In the final weeks of the semester, students design and implement their own experiments to study Hp urease. This laboratory provides students with an understanding of the importance of biochemistry in human health while empowering them to engage in an active area of research. © 2015 The International Union of Biochemistry and Molecular Biology.

  9. Third Semester and Master’s Thesis Ideas 2016

    DEFF Research Database (Denmark)

    The following pages contain a list of project ideas proposed by the scientific staff at the Department of Civil Engineering, Aalborg University, and a number of companies. The project ideas in this catalogue may form the basis for long and short master projects as well as regular 3rd semester...... overview of the purpose as well as the main activities. Further, a weighting between theoretical analysis, experimental work and computer modelling has been proposed. Usually, this weighting can be changed slightly in accordance with the wishes of the students. The contact persons listed will usually act...... in this catalogue can reveal the expertise and research areas of the different supervisors. Many private engineering companies have a homepage on which they state that they would like to collaborate with students on a master project. Find out more on the individual company home pages....

  10. SERS sensors for DVD platform

    DEFF Research Database (Denmark)

    Brøgger, Anna Line

    This Ph.D. thesis explores the engineering of a portable sensor system for detection of rare and small molecules. The Ph.D. project is part of the research project 'Multi-Sensor DVD platform' (MUSE), aiming to integrate different sensors on a rotating disc. The sensors are chosen to complement each...... other, creating more reliable and stable results for the end user. The rotating disc comprises microfluidic channels, which can be utilized for handling and manipulating liquid samples such as blood or water. The focus of this Ph.D. thesis, is on the integration of one specific sensor on a rotating disc....... The sensor is based upon surface enhanced Raman spectroscopy (SERS), which detects molecular vibrations. The aim of this thesis is to cover the different aspects of the sensor system. SERS substrates, consisting of nanopillars with gold or silver caps on top, have been fabricated by standard micro and nano...

  11. Security effectiveness review (SER)

    International Nuclear Information System (INIS)

    Kouprianova, I.; Ek, D.; Showalter, R.; Bergman, M.

    1998-01-01

    As part of the on-going DOE/Russian MPC and A activities at the Institute of Physics and Power Engineering (IPPE) and in order to provide a basis for planning MPC and A enhancements, an expedient method to review the effectiveness of the MPC and A system has been adopted. These reviews involve the identification of appropriate and cost-effective enhancements of facilities at IPPE. This effort requires a process that is thorough but far less intensive than a traditional vulnerability assessment. The SER results in a quick assessment of current and needed enhancements. The process requires preparation and coordination between US and Russian analysts before, during, and after information gathering at the facilities in order that the analysis is accurate, effective, and mutually agreeable. The goal of this paper is to discuss the SER process, including the objectives, time scale, and lessons learned at IPPE

  12. Gender Disparities in Second-Semester College Physics: The Incremental Effects of a "Smog of Bias"

    Science.gov (United States)

    Kost-Smith, Lauren E.; Pollock, Steven J.; Finkelstein, Noah D.

    2010-01-01

    Our previous research [Kost et al., Phys. Rev. ST Phys. Educ. Res. 5, 010101 (2009)] examined gender differences in the first-semester, introductory physics class at the University of Colorado at Boulder. We found that: (1) there were gender differences in several aspects of the course, including conceptual survey performance, (2) these…

  13. A Semester-Long Project-Oriented Biochemistry Laboratory Based on "Helicobacter pylori" Urease

    Science.gov (United States)

    Farnham, Kate R.; Dube, Danielle H.

    2015-01-01

    Here we present the development of a 13 week project-oriented biochemistry laboratory designed to introduce students to foundational biochemical techniques and then enable students to perform original research projects once they have mastered these techniques. In particular, we describe a semester-long laboratory that focuses on a biomedically…

  14. Podcast Effectiveness as Scaffolding Support for Students Enrolled in First-Semester General Chemistry Laboratories

    Science.gov (United States)

    Powell, Mary Cynthia Barton

    2010-01-01

    Podcasts covering essential first-semester general chemistry laboratory techniques and central concepts that aid in experimental design or data processing were prepared and made available for students to access on an as-needed basis on iPhones [arrow right] or iPod touches [arrow right]. Research focused in three areas: the extent of podcast…

  15. Predicting College Success: Achievement, Demographic, and Psychosocial Predictors of First-Semester College Grade Point Average

    Science.gov (United States)

    Saltonstall, Margot

    2013-01-01

    This study seeks to advance and expand research on college student success. Using multinomial logistic regression analysis, the study investigates the contribution of psychosocial variables above and beyond traditional achievement and demographic measures to predicting first-semester college grade point average (GPA). It also investigates if…

  16. SERS Engineering Collaboration

    Science.gov (United States)

    2012-06-01

    laser beam. In the second approach, a pulsed laser was used to texture a silicon wafer to form sharp features. Silver was evaporated onto the wafer...orders of magnitude larger than that measured on a gold nanoparticle array on a glass substrate. The largest SERS enhancement for a silver device was...surface plasmons," Yizhuo Chu and Kenneth B. Crozier, Optics Letters vol. 34, 244 (2009) K3. "Gold nanorings as substrates for surface-enhanced Raman

  17. Relationship Between the Perception Curriculum Credit Semester System (Sks) with Academic Achievement Motivation in Students of Sman 78 Jakarta

    OpenAIRE

    Nurhidayah, Fajriati; Widodo, Prasetyo Budi; Desiningrum, Dinie Ratri

    2012-01-01

    School education has a major role in improving the quality of eduvation ,00aitems through the students academic achievement motivation. Students academic achievement motivation can be seen by the student perception of the curriculum semester credit system is applied in schools. This research was conducted to determine the relationship between perceptions of curriculum semester credit system with academic achievement motivation in students of SMAN 78 Jakarta. The population was 324 students w...

  18. Review on SERS of Bacteria

    Directory of Open Access Journals (Sweden)

    Pamela A. Mosier-Boss

    2017-11-01

    Full Text Available Surface enhanced Raman spectroscopy (SERS has been widely used for chemical detection. Moreover, the inherent richness of the spectral data has made SERS attractive for use in detecting biological materials, including bacteria. This review discusses methods that have been used to obtain SERS spectra of bacteria. The kinds of SERS substrates employed to obtain SERS spectra are discussed as well as how bacteria interact with silver and gold nanoparticles. The roll of capping agents on Ag/Au NPs in obtaining SERS spectra is examined as well as the interpretation of the spectral data.

  19. Typewriting--Less-Than-a-Semester Credit Basis

    Science.gov (United States)

    Schramm, Dwayne

    1974-01-01

    Five advantages to be gained in teaching typing in a time structure less rigid than the traditional semester are itemized. The implications for typewriting teachers as a more individualized approach is used are considered. (AG)

  20. Single molecule SERS: Perspectives of analytical applications

    Czech Academy of Sciences Publication Activity Database

    Vlčková, B.; Pavel, I.; Sládková, M.; Šišková, K.; Šlouf, Miroslav

    834-836, - (2007), s. 42-47 ISSN 0022-2860. [European Congress on Molecular Spectroscopy /28./. Istanbul, 03.09.2006-08.09.2006] R&D Projects: GA ČR GA203/04/0688 Institutional research plan: CEZ:AV0Z40500505 Keywords : surface-enhanced Raman scattering (SERS) * surface-enhanced resonance Raman (SERRS) * single molecule SERS Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.486, year: 2007

  1. Quiero ser citado

    Directory of Open Access Journals (Sweden)

    Leonardo Romero

    2011-05-01

    Full Text Available Después de varios años de ser editor, muchos de mis jefes confunden la revista con el editor, y es común oír cosas como “conferencia a cargo de la revista” o en conversaciones se dirijan a mí para decir “y porque no te citan”, refiriéndose al motivo porqué la Rev peru biol. no es citada por otros trabajos. Aprovechando ese desquicio, en los siguientes párrafos encarnare a la revista y al editor, en la fusión mágica en la que algunos de mis jefes me imaginan.

  2. Editorial, n.1 second semester 2006

    Directory of Open Access Journals (Sweden)

    Francisco das Chagas de Souza

    2006-12-01

    Full Text Available Carta do Editor Pesquisa e geração de conhecimento O cenário à nossa frente, cotidianamente propõe demandas que exigem um olhar com maior ou menor profundidade e em busca de respostas com maior ou menor urgência. Isso dá-se em conformidade ao perfil do contexto sócio-histórico onde estejamos atuando, ora como pesquisadores ou profissionais técnicos, ora como docentes ou gestores de unidades de informação ou instituições acadêmicas e de investigação, ora como consultores ou instrutores. É assim, porque cada vez mais somos capazes de gerar novos conhecimentos resultantes da atividade, hoje estruturante da realidade, que se apresenta como a pesquisa acadêmico-científica. Mas o cenário gerador das questões é de amplitude global quanto às razões epistemológicas e cognitivas, sendo os meios disponíveis para o exercício da produção de conhecimento de alcance local, pois, resultam das possibilidades econômicas proporcionadas pela sociedade de cada região ou país. Tais possibilidades se estabelecem em função da inserção de cada sociedade específica no universo das trocas internacionais de mercadorias, em que também participa o conhecimento como um bem negociável. Portanto, no conjunto dos bens capazes de promover a geração de recursos que possam ser distribuídos, também, para os centros produtores do conhecimento científico o próprio conhecimento construído participa com maior ou menor valor; isso se dá na razão direta do desenvolvimento e atualidade das pesquisas e da capacidade inventiva e inovadora dos cientistas e da ciência quanto à argüição da realidade posta pelo cenário global. Um elo que, historicamente, reduz entre os vários países o impacto da desigualdade interposta pelas condições estritamente locais, advém do esforço dos pesquisadores em se enxergarem como pares de uma mesma comunidade, em cada campo científico, e a partir disso articularem as relações de interc

  3. INTEGRATING GEOSPATIAL TECHNOLOGIES AND SECONDARY STUDENT PROJECTS: THE GEOSPATIAL SEMESTER

    Directory of Open Access Journals (Sweden)

    Bob Kolvoord

    2012-12-01

    Full Text Available Resumen:El Semestre Geoespacial es una actividad de educación geográfica centrada en que los estudiantes del último curso de secundaria en los institutos norteamericanos, adquieran competencias y habilidades específicas en sistemas de información geográfica, GPS y teledetección. A través de una metodología de aprendizaje basado en proyectos, los alumnos se motivan e implican en la realización de trabajos de investigación en los que analizan, e incluso proponen soluciones, diferentes procesos, problemas o cuestiones de naturaleza espacial. El proyecto está coordinado por la Universidad James Madison y lleva siete años implantándose en diferentes institutos del Estado de Virginia, implicando a más de 20 centros educativos y 1.500 alumnos. Los alumnos que superan esta asignatura de la enseñanza secundaria obtienen la convalidación de determinados créditos académicos de la Universidad de referencia.Palabras clave:Sistemas de información geográfica, enseñanza, didáctica de la geografía, semestre geoespacial.Abstract:The Geospatial Semester is a geographical education activity focused on students in their final year of secondary schools in the U.S., acquiring specific skills in GIS, GPS and remote sensing. Through a methodology for project-based learning, students are motivated and involved in conducting research using geographic information systems and analyze, and even propose solutions, different processes, problems or issues spatial in nature. The Geospatial Semester university management not only ensures proper coaching, guidance and GIS training for teachers of colleges, but has established a system whereby students who pass this course of secondary education gain the recognition of certain credits from the University.Key words:Geographic information system, teaching, geographic education, geospatial semester. Résumé:Le semestre géospatial est une activité axée sur l'éducation géographique des étudiants en derni

  4. Aprendendo a ser psicoterapeuta

    Directory of Open Access Journals (Sweden)

    Elizabeth Amelio Faleiros

    Full Text Available Este estudo investiga, na perspectiva de Jacob Levy Moreno, a concepção que alunos de Psicologia têm sobre o que é ser psicoterapeuta, quais elementos são necessários para o desenvolvimento dessa tarefa e os fatores impeditivos para realizá-la. Propõe formas de soluções para o desempenho daquela função, favorecendo a reflexão sobre a importância dessa tarefa e a responsabilidade do profissional junto ao paciente. A metodologia utilizada é a qualitativa, pois esta permite abordar dimensões da subjetividade dos sujeitos. Os resultados revelam que os alunos possuem em sua concepção os alicerces básicos, cujos indicadores são apontados por Moreno e por outros autores, percebem os requisitos básicos que constituem a essência do papel de terapeuta, evidenciam críticas realistas sobre os fatores limitadores e sugerem ações pedagógicas para minimizá-los.

  5. Special Semester titled Geometric mechanics : variational and stochastic methods : CIB, Lausanne, Switzerland, January-June 2015

    CERN Document Server

    Cruzeiro, Ana; Holm, Darryl

    2017-01-01

    Collecting together contributed lectures and mini-courses, this book details the research presented in a special semester titled “Geometric mechanics – variational and stochastic methods” run in the first half of 2015 at the Centre Interfacultaire Bernoulli (CIB) of the Ecole Polytechnique Fédérale de Lausanne. The aim of the semester was to develop a common language needed to handle the wide variety of problems and phenomena occurring in stochastic geometric mechanics. It gathered mathematicians and scientists from several different areas of mathematics (from analysis, probability, numerical analysis and statistics, to algebra, geometry, topology, representation theory, and dynamical systems theory) and also areas of mathematical physics, control theory, robotics, and the life sciences, with the aim of developing the new research area in a concentrated joint effort, both from the theoretical and applied points of view. The lectures were given by leading specialists in different areas of mathematics a...

  6. What Did You Try Last Semester? How Did It Work?

    Science.gov (United States)

    Moore, John W.

    1999-02-01

    As I write this, the end of the semester is less than a week away. This is a good time to reflect on what I tried this time that I had not done before, how well it worked, and how that applies to the process of change and reform in chemical education. Nearly a year ago, a good friend gave me a copy of a brief note by the Executive Director of the National Science Teachers Association, Gerald Wheeler (1). Its title was "Why doesn't change stick?" Quoting the Red Queen from Alice in Wonderland, Wheeler suggested that it might be taking all the running we could do just to maintain the status quo. He asked readers to look systematically at "the failed reform efforts begun in the 1960s" and questioned whether those efforts had actually changed anything. Although the reform efforts Wheeler questioned were aimed at the pre-college level, his point is a good one for college as well as high school teachers to consider, especially at a time when new projects are aiming to reform science education systemically. (See pages 158-160 and page 163 for more information on these projects.) If reform efforts are typically meteoric, burning brightly for but a short time and then disappearing, what might we do to make them less so? I think that the power to make reform less meteoric lies within all of us. It involves incremental, rather than revolutionary, change. My model for reform is one in which each of us continually experiments with manageable changes in courses and pedagogy, evaluating their effectiveness, casting out the less than successful ones, retaining and refining those that help students learn more effectively, and keeping the rest of the community informed about what works and what does not. This model requires continual work and dedication from all of us, but not superhuman effort that is impossible to sustain over the long term. A meteor shower definitely gets our attention, but far more light is shed by the fixed stars, and they'll still be there next week. The

  7. Rendezvous with the World: Missouri Southern State University's Themed Semesters

    Science.gov (United States)

    Stebbins, Chad

    2011-01-01

    Although most universities emphasize study abroad as the primary vehicle to internationalize the campus, in reality only a small percentage of students actually participate in this endeavor. The internationally themed semesters at Missouri Southern State University (MSSU) reach virtually every student, and provide a global perspective and cultural…

  8. 3rd Semester and Master’s Thesis Ideas 2011

    DEFF Research Database (Denmark)

    The report contain a list of project ideas proposed by the scientific staff at the Department of Civil Engineering, Aalborg University, and a number of companies. Most of the project ideas in this catalogue may form the basis for long and short candidate projects as well as regular 3rd semester...

  9. 3rd Semester and Master’s Thesis Ideas 2012

    DEFF Research Database (Denmark)

    Clausen, Johan

    The report contain a list of project ideas proposed by the scientific staff at the Department of Civil Engineering, Aalborg University, and a number of companies. Most of the project ideas in this catalogue may form the basis for long and short candidate projects as well as regular 3rd semester...

  10. Holistic Wellness and Its Impact on First-Semester Grades

    Science.gov (United States)

    Cereola, Sandy J.; Snyder, Cathleen S.; Cereola, Ronald J.; Horton, Brett W.

    2014-01-01

    Students enrolled in a first-semester, critical-thinking course assessed their perception of their own wellness using a 52-question survey. Within the survey, holistic wellness was measured along seven dimensions: (a) physical, (b) intellectual, (c) social, (d) occupational, (e) spiritual, (f) emotional, and (g) environmental. Individual…

  11. Development of a Semester-Long, Inquiry-Based Laboratory Course in Upper-Level Biochemistry and Molecular Biology

    Science.gov (United States)

    Murthy, Pushpalatha P. N.; Thompson, Martin; Hungwe, Kedmon

    2014-01-01

    A semester-long laboratory course was designed and implemented to familiarize students with modern biochemistry and molecular biology techniques. The designed format involved active student participation, evaluation of data, and critical thinking, and guided students to become independent researchers. The first part of the course focused on…

  12. Reassessing SERS enhancement factors: using thermodynamics to drive substrate design.

    Science.gov (United States)

    Guicheteau, J A; Tripathi, A; Emmons, E D; Christesen, S D; Fountain, Augustus W

    2017-12-04

    Over the past 40 years fundamental and application research into Surface-Enhanced Raman Scattering (SERS) has been explored by academia, industry, and government laboratories. To date however, SERS has achieved little commercial success as an analytical technique. Researchers are tackling a variety of paths to help break through the commercial barrier by addressing the reproducibility in both the SERS substrates and SERS signals as well as continuing to explore the underlying mechanisms. To this end, investigators use a variety of methodologies, typically studying strongly binding analytes such as aromatic thiols and azarenes, and report SERS enhancement factor calculations. However a drawback of the traditional SERS enhancement factor calculation is that it does not yield enough information to understand substrate reproducibility, application potential with another analyte, or the driving factors behind the molecule-metal interaction. Our work at the US Army Edgewood Chemical Biological Center has focused on these questions and we have shown that thermodynamic principles play a key role in the SERS response and are an essential factor in future designs of substrates and applications. This work will discuss the advantages and disadvantages of various experimental techniques used to report SERS enhancement with planar SERS substrates and present our alternative SERS enhancement value. We will report on three types of analysis scenarios that all yield different information concerning the effectiveness of the SERS substrate, practical application of the substrate, and finally the thermodynamic properties of the substrate. We believe that through this work a greater understanding for designing substrates will be achieved, one that is based on both thermodynamic and plasmonic properties as opposed to just plasmonic properties. This new understanding and potential change in substrate design will enable more applications for SERS based methodologies including targeting

  13. Perceived autonomy in the first semester of mathematics studies

    OpenAIRE

    Liebendörfer, Michael; Hochmuth, Reinhard

    2015-01-01

    International audience; We focus on the perceived autonomy of mathematics students in their first semester at university. According to self-determination theory by Deci and Ryan (1985), students have to satisfy their need for autonomy in order to develop intrinsic motivation. Using two facets of autonomy, we analyse interview data to explore which situations foster or hinder the students' perceived autonomy. The main factors affecting students' autonomy are briefly discussed.

  14. Stamping SERS for creatinine sensing

    Science.gov (United States)

    Li, Ming; Du, Yong; Zhao, Fusheng; Zeng, Jianbo; Santos, Greggy M.; Mohan, Chandra; Shih, Wei-Chuan

    2015-03-01

    Urine can be obtained easily, readily and non-invasively. The analysis of urine can provide metabolic information of the body and the condition of renal function. Creatinine is one of the major components of human urine associated with muscle metabolism. Since the content of creatinine excreted into urine is relatively constant, it is used as an internal standard to normalize water variations. Moreover, the detection of creatinine concentration in urine is important for the renal clearance test, which can monitor the filtration function of kidney and health status. In more details, kidney failure can be imminent when the creatinine concentration in urine is high. A simple device and protocol for creatinine sensing in urine samples can be valuable for point-of-care applications. We reported quantitative analysis of creatinine in urine samples by using stamping surface enhanced Raman scattering (S-SERS) technique with nanoporous gold disk (NPGD) based SERS substrate. S-SERS technique enables label-free and multiplexed molecular sensing under dry condition, while NPGD provides a robust, controllable, and high-sensitivity SERS substrate. The performance of S-SERS with NGPDs is evaluated by the detection and quantification of pure creatinine and creatinine in artificial urine within physiologically relevant concentration ranges.

  15. ser en ortodoncia

    OpenAIRE

    Ruíz-Esculpi, María; Ricse-Chaupis, Estela; Villanueva-Vega, Judith; Torres-Maita, Liz

    2014-01-01

    La primera aplicación del láser en un diente fue realizada en 1965. Desde entonces ha presentado una constante evolución y desarrollo. La tecnología láser permite realizar procedimientos en tejidos duros y blandos, pudiendo ser utilizado con las siguientes finalidades: como prevención de la desmineralización, en la adhesión y remoción de brackets, en la reducción del dolor producto del movimiento dental, en la reparación ósea después de la expansión, en diversas cirugías y otras aplicaciones ...

  16. The Impact of Structural Competence towards Speaking Competence of the Fourth Semester Students of English Department

    Directory of Open Access Journals (Sweden)

    Muhammad Nafi Annury

    2013-11-01

    Full Text Available This paper tries to define any impact of structural competence towards speaking competence. In this research, the writer used descriptive co-relational method. It was used to describe whether there was an impact between two variables, i.e. structural competence (X as independent variable and speaking competence (Y as dependent variable. The subject of study was the fourth semester students of English department of Tarbiyah Faculty IAIN Walisongo Semarang. After the data had been analyzed, it was found that there was significant impact of structural competence especially in appropriateness. It helped students to arrange words into sentences that they utter.

  17. La importancia de ser grande

    OpenAIRE

    Baisre, J. A.

    2007-01-01

    Se responde a las preguntas ¿por qué los mamíferos marinos son los animales más grandes del planeta?, ¿Por qué los peces no pueden ser más grandes?. Éstas y otras interrogantes son respondidas de forma sencilla y clara.

  18. Third Semester and Master’s Thesis Ideas 2017

    DEFF Research Database (Denmark)

    The following pages contain a list of project ideas proposed by the scientific staff at the Department of Civil Engineering, Aalborg University, and a number of companies. The project ideas in this catalogue may form the basis for long and short master projects as well as regular 3rd semester...... as supervisors. Questions regarding details about each proposed project should be directed at the contact persons. The contact details can be found via a person search on the university home page. Furthermore, other ideas for projects may be discussed with a potential supervisor. In this aspect the proposals...

  19. A real CDIO mechanical engineering project in 4th semester

    DEFF Research Database (Denmark)

    Lauritsen, Aage Birkkjær

    In the past 6 years at the mechanical engineering study at the Engineering College of Aarhus we have been practicing project work on 4th Semester in the design of energy technology systems. In my presentation, I will give a description of the project, and the thoughts behind; pedagogic......-6 students, and will partly support the general theory being taught in the courses, but will also provide students with skills in teamwork, project work and system building. The pedagogical considerations behind the development of the project are quite simply that students learn best through active work...

  20. Impact of the second semester University Modeling Instruction course on students’ representation choices

    Directory of Open Access Journals (Sweden)

    Daryl McPadden

    2017-11-01

    Full Text Available Representation use is a critical skill for learning, problem solving, and communicating in science, especially in physics where multiple representations often scaffold the understanding of a phenomenon. University Modeling Instruction, which is an active-learning, research-based introductory physics curriculum centered on students’ use of scientific models, has made representation use a primary learning goal with explicit class time devoted to introducing and coordinating representations as part of the model building process. However, because of the semester break, the second semester course, Modeling Instruction-Electricity and Magnetism (MI-EM, contains a mixture of students who are returning from the Modeling Instruction-mechanics course (to whom we refer to as “returning students” and students who are new to Modeling Instruction with the MI-EM course (to whom we refer to as “new students”. In this study, we analyze the impact of MI-EM on students’ representation choices across the introductory physics content for these different groups of students by examining both what individual representations students choose and their average number of representations on a modified card-sort survey with a variety of mechanics and EM questions. Using Wilcoxon-signed-rank tests, Wilcoxon-Mann-Whitney tests, Cliff’s delta effect sizes, and box plots, we compare students’ representation choices from pre- to postsemester, from new and returning students, and from mechanics and EM content. We find that there is a significant difference between returning and new students’ representation choices, which serves as a baseline comparison between Modeling Instruction and traditional lecture-based physics classes. We also find that returning students maintain a high representation use across the MI-EM semester, while new students see significant growth in their representation use regardless of content.

  1. On flipping first-semester calculus: a case study

    Science.gov (United States)

    Petrillo, Joseph

    2016-05-01

    High failure rates in calculus have plagued students, teachers, and administrators for decades, while science, technology, engineering, and mathematics programmes continue to suffer from low enrollments and high attrition. In an effort to affect this reality, some educators are 'flipping' (or inverting) their classrooms. By flipping, we mean administering course content outside of the classroom and replacing the traditional in-class lectures with discussion, practice, group work, and other elements of active learning. This paper presents the major results from a three-year study of a flipped, first-semester calculus course at a small, comprehensive, American university with a well-known engineering programme. The data we have collected help quantify the positive and substantial effects of our flipped calculus course on failure rates, scores on the common final exam, student opinion of calculus, teacher impact on measurable outcomes, and success in second-semester calculus. While flipping may not be suitable for every teacher, every student, and in every situation, this report provides some evidence that it may be a viable option for those seeking an alternative to the traditional lecture model.

  2. Communication skills program in the first semester: An experience report

    Directory of Open Access Journals (Sweden)

    Rafaela Liberali

    2016-01-01

    Full Text Available Since 2001, Brazilian Guidelines for undergraduate medical education highlighted the need to include communication skills (CS in the curriculum. At the Federal University of Santa Catarina (South Brazil, CS were taught in the third year in theoretical classes as an overview of physician-patient relationships, and in a nonsystematic way in practical classes. In 2013, theory and practice were aligned, mediated by reflection, by adding three classes: CS overview; responding to strong emotions; and giving bad news. Two Portuguese translation of modules from DocCom, a web-based audiovisual learning resource on CS in Healthcare (AACH, DUCOM, 2005- 2015, were used. In 2015, we started to teach CS to the 53 students registered in the first semester of our medical course. We report on the program in the first semester of the course and students’ perceptions of it. The CS program consisted of seven 1.5-hr face-to-face sessions with all students, co-taught by the authors, a PhD student and a medical school professor. The content included CS overview and importance in healthcare; relationship-centered care, building relationships and gathering information; students’ experiences in the medical course; and Myers-Briggs Type Indicator (MBTI. To encourage continuous reflection and align theory with practice, before or after theoretical brief presentations, additional resources were used: exercises to raise awareness of verbal and nonverbal communication, drawings on medical students’ life experiences, reflections about the poem “After a While” by Veronica Shoffstall and after listening to Bach’s Brandenburg concerto #1; DocCom modules #6 “Build a relationship” and #8 “Gather information” (viewed online to prepare for class followed by face-toface small group discussions (6-7 students in each about CS learned and theirs practice in role-play; peers’ and patients’ interviews; students’ MBTI identification (at distance and group dynamics

  3. A one-semester course in modeling of VSLI interconnections

    CERN Document Server

    Goel, Ashok

    2015-01-01

    Quantitative understanding of the parasitic capacitances and inductances, and the resultant propagation delays and crosstalk phenomena associated with the metallic interconnections on the very large scale integrated (VLSI) circuits has become extremely important for the optimum design of the state-of-the-art integrated circuits. More than 65 percent of the delays on the integrated circuit chip occur in the interconnections and not in the transistors on the chip. Mathematical techniques to model the parasitic capacitances, inductances, propagation delays, crosstalk noise, and electromigration-induced failure associated with the interconnections in the realistic high-density environment on a chip will be discussed. A One-Semester Course in Modeling of VLSI Interconnections also includes an overview of the future interconnection technologies for the nanotechnology circuits.

  4. AN ANALYSIS OF STUDENTS’ SPEAKING ABILITY IN ENGLISH CONVERSATION CLUB (ECC PROGRAM AT THE 3rd SEMESTER

    Directory of Open Access Journals (Sweden)

    M. Fadhly Farhy Abbas

    2017-07-01

    Full Text Available This research is based on students’ speaking ability who had followed the EnglishConversation Club (ECC program especially for the third semester of English Department. Thepurpose of this study was to analyze the students’ speaking ability at the 3rd semester in the EnglishConversation Club FKIP UNILAK Pekanbaru. The type of the research was mixed method in typeof explanatory design. The number of participant was 53 students. The researcher used twoinstruments, those were test and interview. In analyzing the data, it used in descriptive statistics.The result of the analysis showed that the average score of 3rd semester students’ speaking abilitywas 45.42. It can be concluded that the students’ speaking ability was categorized into failed . Thescore of Standard Deviation was 7.02, Variance was 49.30, and Range was 36 points . It meansthat the students’ speaking ability was homogeneous. According to the Z-Score, it can be seen that49.06% students’ ability was higher than average and 50.94% students ability was below theaverage. In conclusion, the students’ ability in learning speaking English was failed, it had beenaffected by some factors, those were lack of vocabulary, grammar and motivation. It was supportedby the interview, eventhough the students’ perception to English Conversation Club (ECCprogram was positive, but in fact, the students’ frequency to speak English was seldom, they wereless practice speaking English everyday.Keywords : Speaking , English Conversation Club (ECC

  5. The Content Analysis, Material Presentation, and Readability of Curriculum 2013 Science Textbook for 1st Semester of Junior High School 7th Grade

    Directory of Open Access Journals (Sweden)

    Endik Deni Nugroho

    2017-07-01

    Full Text Available Based on the early observation by researchers of the two Science textbooks 7thGrade about biological material, 1stand 2ndsemester of curriculum 2013, there were errors in the material presentation and legibility. This study aimed to compare and find the contents suitability of the book based on standard of competence and basic competences, readability, materials presentation and supporting material in the science textbook VII grade, 1st and 2nd semester and measured student legibility. This study used a qualitative descriptive approach by using document analysis. The data resources were obtained by using purposive, the data collection was triangulation, data analysis was inductive/qualitative and the results emphasized the meaning. This research results showed that the Integrated Sciences and Sciences textbook 1st and 2nd semester meet the standards of the core competencies and basic competence on the syllabus curriculum 2013 and also meet the books standart. The results of the analysis conducted in misstatement concept and principles and material llustration in the Integrated Science textbook 1st semester were found 5 misstatement concept, for the presentation of the principles and material illustration was found no error. In the book Integrated Sciences there was no delivery errors concept, principle, and material illustration. Science textbook 1st semester found 8 concepts misstatements and 8 illustration material misstatements. In general, Integrated Sciences and Sciences textbooks 1st and 2nd semester are illegibility so not appropriate for students.

  6. Tuning SERS for living erythrocytes

    DEFF Research Database (Denmark)

    Brazhe, Nadezda; Parshina, E.Y.; Khabanova, V.V.

    2013-01-01

    Surface-enhanced Raman spectroscopy (SERS) is a unique technique to study submembrane hemoglobin (Hbsm) in erythrocytes. We report the detailed design of SERS experiments on living erythrocytes to estimate dependence of the enhancemen t factor for main Raman bands of Hbsm on silver nanoparticle (Ag......NP) properties. We demonstrate that the enhancement factor for 4/A1g, 10/B1g and A2g Raman bands of Hbsm varies from 105 to 107 under proposed experimental conditions with 473 nm laser excitation. For the first time we show that the enhancement of Raman scattering increases with the increase in the relative...... between small AgNPs and Hbsm and, consequently, leads to the higher enhancement of Raman scattering of Hbsm. The enhancement of higher wavenumber bands 10/B1g and A2g is more sensitive to AgNPs' size and the relative amount of small AgNPs than the enhancement of the lower wavenumber band 4/A1g. This can...

  7. por láser

    Directory of Open Access Journals (Sweden)

    Mayra Garcimuño

    2013-01-01

    Full Text Available En el presente trabajo, la técnica Espectroscopia de plasmas producidos por láser (Laser-induced breakdown spectroscopy –LIBS– se aplicó a la determinación cuan- titativa de Na en agua natural dulce, de interés en agricultura para el estudio de la alcalinidad de aguas de regadío. Para efectuar el análisis, se prepararon soluciones con concentraciones conocidas del analito, se mezclaron con óxido de calcio y se compactaron en pastillas sólidas. Los plasmas se produjeron en aire a presión atmos- férica utilizando un láser pulsado Nd:YAG. Se construyó una curva de calibración y se calculó el límite de detección. Se analizaron muestras de agua natural y los resultados se compararon con los obtenidos mediante espectroscopia de absorción atómica. Se demostró la factibilidad del método para la determinación de Na en agua natural dulce.

  8. GANGGUAN CEMAS PADA MAHASISWA SEMESTER I DAN VII PROGRAM STUDI PENDIDIKAN DOKTER FAKULTAS KEDOKTERAN UNIVERSITAS UDAYANA

    Directory of Open Access Journals (Sweden)

    Dyah Chandratika

    2015-05-01

    Full Text Available Penting untuk dilakukan penelitian mengenai gangguan cemas pada mahasiswa kedokteran karena tingginya tingkat stres mahasiswa terutama pada tahun pertama perkuliahan. Tujuan penelitian ini adalah untuk mengetahui prevalensi dan perbedaan skor  gangguan  cemas  pada mahasiswa  semester  I dan  VII serta untuk  mengetahui perbedaan skor gangguan cemas antara mahasiswa laki-laki dan perempuan di Fakultas Kedokteran Universitas Udayana. Desain penelitian ini adalah cross sectional analitik. Pengambilan sampel dilakukan secara random sampling. Sampel mengisi identitas, kuesioner L-MMPI, kuesioner Hamilton Anxiety Rating Scale (HARS. Kemudian dihitung prevalensi gangguan cemas tiap kelompok serta data dianalisis menggunakan uji t-independen. Terdapat 15 orang (25,0% mahasiswa semester I dan 7 orang (11,7% mahasiswa semester VII yang mengalami gangguan cemas. Dari hasil uji t-independen antara skor gangguan cemas mahasiswa semester I dan VII diperoleh nilai p = 0,001 (<0,05. Sedangkan diperoleh p = 0,080 antara mahasiswa laki-laki dan perempuan pada semester I dan p = 0,744 antara mahasiswa laki-laki dan perempuan pada semester VII. Prevalensi gangguan cemas pada mahasiswa semester I yaitu 25,0% sedangkan 11,7% pada mahasiswa semester VII. Terdapat perbedaan bermakna antara skor gangguan cemas mahasiswa semester I dan VII. Tidak ditemukan perbedaan bermakna skor gangguan cemas antara laki-laki dan perempuan.   

  9. Ser do tempo em Bergson

    OpenAIRE

    Coelho,Jonas Gonçalves

    2004-01-01

    O artigo apresenta a concepção bergsoniana de duração. Pretende-se mostrar que, segundo Bergson, o tempo dos filósofos e cientistas é um tempo fictício, um esquema espacial que oculta a natureza do tempo real, o qual não pode ser separado dos acontecimentos físicos e psicológicos. Para Bergson, o tempo real é sucessão, continuidade, mudança, memória e criação. El presente artículo trata de la concepción bergsoniana de duración. Pretendemos mostrar que, según Bergson, el tiempo de los filós...

  10. Ser do tempo em Bergson

    OpenAIRE

    Coelho, Jonas Gonçalves

    2004-01-01

    O artigo apresenta a concepção bergsoniana de duração. Pretende-se mostrar que, segundo Bergson, o tempo dos filósofos e cientistas é um tempo fictício, um esquema espacial que oculta a natureza do tempo real, o qual não pode ser separado dos acontecimentos físicos e psicológicos. Para Bergson, o tempo real é sucessão, continuidade, mudança, memória e criação. We considered Bergson's duration concept. We intended to show that, according to Bergson, the time of philosophers and scientists i...

  11. for SERS and Photocatalytic Applications

    Directory of Open Access Journals (Sweden)

    Xue Chen

    2011-01-01

    Full Text Available ZnS/Si nanocables were synthesized via a simple two-step thermal evaporation method. The shape and diameter of the ZnS/Si nanocables can be controlled by adjusting the morphologies of the ZnS nanostructures (nanowire or nanoribbon obtained in the first step and the deposition time of the Si shell in the second step, respectively. Furthermore, we obtained polycrystalline Si nanotubes with different shapes and diameters by etching away the inner ZnS core. The as-prepared Si nanotubes were employed as SERS-active substrates, which exhibited a high sensitivity for the detection of R6G. The Si nanotubes also showed effective photocatalytic activity on the decomposition of R6G under the irradiation of visible light.

  12. Exercises in statistics for HA & HA(dat.) & BSc(B), 3rd semester

    DEFF Research Database (Denmark)

    The booklet contains excercises to be used for the tutorials related to the 3rd semester course in statistics on the bachelors progarmme at the Aarhus School of Business.......The booklet contains excercises to be used for the tutorials related to the 3rd semester course in statistics on the bachelors progarmme at the Aarhus School of Business....

  13. Undergraduates in a Sustainability Semester: Models of Social Change for Sustainability

    Science.gov (United States)

    Miller, Hannah K.

    2016-01-01

    Interdisciplinary sustainability programs are emerging globally, but little is known about the learning in these educational contexts. This qualitative case study examined undergraduates' experience in a Sustainability Semester, using the agency/structure dialectic as a theoretical lens. Before the semester, students' models of change for…

  14. The European Project Semester at ISEP: The Challenge of Educating Global Engineers

    Science.gov (United States)

    Malheiro, Benedita; Silva, Manuel; Ribeiro, Maria Cristina; Guedes, Pedro; Ferreira, Paulo

    2015-01-01

    Current engineering education challenges require approaches that promote scientific, technical, design and complementary skills while fostering autonomy, innovation and responsibility. The European Project Semester (EPS) at Instituto Superior de Engenharia do Porto (ISEP) (EPS@ISEP) is a one semester project-based learning programme (30 European…

  15. College cafeteria snack food purchases become less healthy with each passing week of the semester.

    Science.gov (United States)

    Wansink, Brian; Cao, Ying; Saini, Prerna; Shimizu, Mitsuru; Just, David R

    2013-07-01

    Snacks, stress and parties all contribute to the weight gain – the elusive ‘Freshman 15’ – that some college-goers unfortunately experience. The present study examines how a` la carte snack choice changes on a university campus during each progressing week of the academic calendar. How a` la carte snack choices change on a university campus with each progressing week of the academic calendar was examined. The data were collected from three large cafeterias (or dining halls) on Cornell University’s campus during four semesters (Fall 2006, Spring 2007, Fall 2007 and Spring 2008), for 18 weeks in each semester. After the a` la carte snack items were divided into healthy snacks and unhealthy snacks, the percentage share for each food category was calculated. Within each semester, the unhealthy snack food choices increased consistently by 0?4% per week (b50?00418, P,0?01). Furthermore, a sharp (8 %) increase occurred in the final two weeks of the semester. In contrast, healthy snack food choices decreased by almost 4% (b520?0408, P,0?01) in the final two weeks during the fall semester. These results demonstrate an increased demand for hedonic, or unhealthy, snack foods as the college semester progresses and in particular at the very end of the semester. To counter this tendency towards unhealthy snacking, cafeterias and stores should make extra effort to promote healthy alternatives during the later weeks of the semester.

  16. A Comprehensive Probability Project for the Upper Division One-Semester Probability Course Using Yahtzee

    Science.gov (United States)

    Wilson, Jason; Lawman, Joshua; Murphy, Rachael; Nelson, Marissa

    2011-01-01

    This article describes a probability project used in an upper division, one-semester probability course with third-semester calculus and linear algebra prerequisites. The student learning outcome focused on developing the skills necessary for approaching project-sized math/stat application problems. These skills include appropriately defining…

  17. The Science Semester: Cross-Disciplinary Inquiry for Prospective Elementary Teachers

    Science.gov (United States)

    Ford, Danielle J.; Fifield, Steve; Madsen, John; Qian, Xiaoyu

    2013-10-01

    We describe the Science Semester, a semester-long course block that integrates three science courses and a science education methods course for elementary teacher education majors, and examine prospective elementary teachers’ developing conceptions about inquiry, science teaching efficacy, and reflections on learning through inquiry. The Science Semester was designed to provide inquiry-oriented and problem-based learning experiences, opportunities to examine socially relevant issues through cross-disciplinary perspectives, and align with content found in elementary curricula and standards. By the end of the semester, prospective elementary teachers moved from naïve to intermediate understandings of inquiry and significantly increased self-efficacy for science teaching as measured on one subscore of the STEBI-B. Reflecting on the semester, prospective teachers understood and appreciated the goals of the course and the PBL format, but struggled with the open-ended and student-directed elements of the course.

  18. PENERAPAN METODE PETA PIKIRAN DALAM MENULIS ESAI MAHASISWA SEMESTER V STKIP YDB LUBUK ALUNG

    Directory of Open Access Journals (Sweden)

    Irawati Rahman

    2016-06-01

    Full Text Available Abstract This research is based on several problems found in students’ writing; (1 the structure of students’ essay is not complete; (2 the use of languge is not communicative; (3 the paragraph development is not coherent; and (4 the title of the essay is not appropriate. This reseach aims at implementing mind mapping technique in writing an essay. Mind mapping is a technique of teaching writing to help students map their idea in writing an essay. This research used quantitative research. The research sample was the fifth semester students of STKIP YBD Lubuk Alung registered in 2015/2016 academic year. The result of this research shows that mind mapping technique could increase students’ writing. This is indicated by the increase of students’ score after applying mind mapping technique. 25 students (92.6% got very good score and 2 others (7.43% got good score. Based on this finding, it is suggested for English teachers to use mind mapping technique to improve students’ writing skill. Kata Kunci: penerapan, teknik mind mapping, keterampilan menulis esai

  19. Entre contener y ser contenido

    Directory of Open Access Journals (Sweden)

    Jorge Morales Meneses

    2016-08-01

    Full Text Available El presente artículo propone una nueva manera de entender los elementos comunes en la formación y el hacer del diseño y de la arquitectura, posibilitando un pensar común y un coactuar en diversas escalas de intervención, necesarias para el manejo de la complejidad del paisaje contemporáneo. La convicción de un pensar común entre ambas disciplinas permite explorar un marco filosófico que incluye a pensadores tan trascendentales como Aristóteles, Kant y Heidegger, estableciendo un orden de pensamiento que los relaciona y sitúa. En momentos en que el territorio está siendo visible y negativamente afectado por elementos no pensados o que fueron imaginados separadamente, este artículo propone una mirada que le dé sentido de totalidad a las acciones del diseño y de la arquitectura, como elementos que permanentemente se contienen en otros de diferente escala, pero que siempre están vinculados. Reconocer el paisaje físico y mental, tangible e intangible que contiene al diseño y a la arquitectura contribuirá a establecer un marco de acción donde todos los elementos construidos por el ser humano puedan tener un rol específico y una escala asumida, e intercomprenderse para mejor utilización de los recursos, disminuir el impacto ambiental y contribuir a un orden social mejor interpretado por los objetos, espacios y sus representaciones.

  20. SERS-based application in food analytics (Conference Presentation)

    Science.gov (United States)

    Cialla-May, Dana; Radu, Andreea; Jahn, Martin; Weber, Karina; Popp, Jürgen

    2017-02-01

    To establish detection schemes in life science applications, specific and sensitive methods allowing for fast detection times are required. Due to the interaction of molecules with strong electromagnetic fields excited at metallic nanostructures, the molecular fingerprint specific Raman spectrum is increased by several orders of magnitude. This effect is described as surface-enhanced Raman spectroscopy (SERS) and became a very powerful analytical tool in many fields of application. Within this presentation, we will introduce innovative bottom-up strategies to prepare SERS-active nanostructures coated with a lipophilic sensor layer. To do so, the food colorant Sudan III, an indirect carcinogen substance found in chili powder, palm oil or spice mixtures, is detected quantitatively in the background of the competitor riboflavin as well as paprika powder extracts. The SERS-based detection of azorubine (E122) in commercial available beverages with different complexity (e.g. sugar content, alcohol concentration) illustrates the strong potential of SERS as a qualitative as well as semiquantitative prescan method in food analytics. Here, a good agreement between the estimated concentration employing SERS as well as the gold standard technique HPLC, a highly laborious method, is found. Finally, SERS is applied to detect vitamin B2 and B12 in cereals as well as the estimate the ratio of lycopene and β-carotene in tomatoes. Acknowledgement: Funding the projects "QuantiSERS" and "Jenaer Biochip Initiative 2.0" within the framework "InnoProfile Transfer - Unternehmen Region" the Federal Ministry of Education and Research, Germany (BMBF) is gratefully acknowledged.

  1. Development and Implementation of a Two-Semester Introductory Organic-Bioorganic Chemistry Sequence: Conclusions from the First Six Years

    Science.gov (United States)

    Goess, Brian C.

    2014-01-01

    A two-semester second-year introductory organic chemistry sequence featuring one semester of accelerated organic chemistry followed by one semester of bioorganic chemistry is described. Assessment data collected over a six-year period reveal that such a course sequence can facilitate student mastery of fundamental organic chemistry in the first…

  2. SERS Technique for Rapid Bacterial Screening

    Science.gov (United States)

    This study reports the feasibility of citrate-reduced colloidal silver SERS for differentiating E. coli, Listeria, and Salmonella. FT-Raman and SERS spectra of both silver colloids and colloid-K3PO4 mixtures were collected and analyzed to evaluate the reproducibility and stability of silver colloids...

  3. Enhancing SERS by Means of Supramolecular Charge Transfer

    Science.gov (United States)

    Wong, Eric; Flood, Amar; Morales, Alfredo

    2009-01-01

    In a proposed method of sensing small quantities of molecules of interest, surface enhanced Raman scattering (SERS) spectroscopy would be further enhanced by means of intermolecular or supramolecular charge transfer. There is a very large potential market for sensors based on this method for rapid detection of chemical and biological hazards. In SERS, the Raman signals (vibrational spectra) of target molecules become enhanced by factors of the order of 108 when those molecules are in the vicinities of nanostructured substrate surfaces that have been engineered to have plasmon resonances that enhance local electric fields. SERS, as reported in several prior NASA Tech Briefs articles and elsewhere, has remained a research tool and has not yet been developed into a practical technique for sensing of target molecules: this is because the short range (5 to 20 nm) of the field enhancement necessitates engineering of receptor molecules to attract target molecules to the nanostructured substrate surfaces and to enable reliable identification of the target molecules in the presence of interferants. Intermolecular charge-transfer complexes have been used in fluorescence-, photoluminescence-, and electrochemistry-based techniques for sensing target molecules, but, until now, have not been considered for use in SERS-based sensing. The basic idea of the proposed method is to engineer receptor molecules that would be attached to nanostructured SERS substrates and that would interact with the target molecules to form receptor-target supramolecular charge-transfer complexes wherein the charge transfer could be photoexcited.

  4. Care and Feeding of Transfer Students: a First-Semester Seminar Helps Students Thrive

    Science.gov (United States)

    Rosser, S.; Sparks, D. W.; Newman, J.

    2016-12-01

    Transfer students from community colleges make up a large and increasingly important part of undergraduate geology majors. These students transferring into a large university are regarded upperclassmen by themselves and the University, but in many ways their development stage is similar to freshmen. These students are also isolated because they are taking classes out of sequence, and not in a cohort. Difficulties in their first semester will affect the rest of their academic career, or even cut it short. The Department of Geology and Geophysics developed a mandatory seminar for transfer students in their first semester. The goals of this seminar are to develop relationships between students in the cohort and with faculty and staff, develop academic success skills and learn how to prepare for and pursue a career in geology and geophysics. Each class meeting starts with a family-style meal, during which academic advisor inquires about their week, encourages them to share any issues or questions that have arisen, and informs them about department events. Then the advisor, a member of the G&G faculty or a representative from campus resources (such as Academic Honor Council, Career Center, Center for Teaching Excellence, Academic Success Center) leads a discussion or gives a presentation. Topics include time management, tutor availability, academic coaching, career paths, research opportunities in the department, and employer expectations. Finally students write a short reflection about that week's meeting and their own experiences. There is also a geological field trip to introduce students to rocks in the field and to the build their relationships with each other and to create a strong transfer cohort. The transfer seminar has been a low-cost and effective strategy to help students thrive. Retention of transfer students beyond the first year has increased, GPA's increased, and significantly more students got involved in undergraduate research projects. Several

  5. SERS-Based Prognosis of Kidney Transplant Outcome

    Science.gov (United States)

    Chi, Jingmao

    the unique SERS spectral features that indicate kidney AR. By integrating SERS analysis with statistical and chemical analysis and with the promising outcomes, this research has made a significant contribution in exploring the frontier of SERS analysis in biomedical sensing and diagnosis.

  6. Characterizing the changes in teaching practice during first semester implementation of an argument-based inquiry approach in a middle school science classroom

    Science.gov (United States)

    Pinney, Brian Robert John

    The purpose of this study was to characterize ways in which teaching practice in classroom undergoing first semester implementation of an argument-based inquiry approach changes in whole-class discussion. Being that argument is explicitly called for in the Next Generation Science Standards and is currently a rare practice in teaching, many teachers will have to transform their teaching practice for inclusion of this feature. Most studies on Argument-Based Inquiry (ABI) agree that development of argument does not come easily and is only acquired through practice. Few studies have examined the ways in which teaching practice changes in relation to the big idea or disciplinary core idea (NGSS), the development of dialogue, and/or the development of argument during first semester implementation of an argument-based inquiry approach. To explore these areas, this study posed three primary research questions: (1) How does a teacher in his first semester of Science Writing Heuristic professional development make use of the "big idea"?, (1a) Is the indicated big idea consistent with NGSS core concepts?, (2) How did the dialogue in whole-class discussion change during the first semester of argument-based inquiry professional development?, (3) How did the argument in whole-class discussion change during the first semester of argument-based inquiry professional development? This semester-long study that took place in a middle school in a rural Midwestern city was grounded in interactive constructivism, and utilized a qualitative design to identify the ways in which the teacher utilized big ideas and how dialogue and argumentative dialogue developed over time. The purposefully selected teacher in this study provided a unique situation where he was in his first semester of professional development using the Science Writing Heuristic Approach to argument-based inquiry with 19 students who had two prior years' experience in ABI. Multiple sources of data were collected, including

  7. USING THINK-PAIR-SHARE TO IMPROVE SPEAKING ACHIEVEMENT OF THE SECOND SEMESTER ENGLISH STUDY PROGRAM OF TRIDINANTI UNIVERSITY PALEMBANG

    Directory of Open Access Journals (Sweden)

    Jenny Elvinna Manurung

    2017-09-01

    Full Text Available The study aimed at improving the speaking achievement of the second semester students of Tridinanti Palembang by using Think-Pair-Share strategy (TPR. This study was an action research study. The steps in conducting the study were planning, actions and observation of action and reflections. The population of the study was all of the second semester students of Tridinanti University in the academic year 2016/2017. The sample used one class (10students. The data collections used by the researcher were tests and observation. The learning improvement indicators included in two things; (1 learning achievement, (2 teaching and learning process. In the study, the implementation was conducted into two cycles. The results showed that the average score of students’ speaking achievement was 66 in cycle I and the observation result was 62.82. The result had not been reached the target yet that was >70. At least more than 85% students could achieve the score above 70. Thus, cycle II was necessary to be implemented. In cycle II, the average score of speaking test was 81and the observation result was 81.06. The students had reached the target and the cycle was stopped. In conclusion, the implementation of TPR had brought significant improvement to the students’ speaking achievement.

  8. Engineering Metal Nanostructure for SERS Application

    Directory of Open Access Journals (Sweden)

    Yanqin Cao

    2013-01-01

    Full Text Available Surface-enhanced Raman scattering (SERS has attracted great attention due to its remarkable enhancement and excellent selectivity in the detection of various molecules. Noble metal nanomaterials have usually been employed for producing substrates that can be used in SERS because of their unique local plasma resonance. As the SERS enhancement of signals depends on parameters such as size, shape, morphology, arrangement, and dielectric environment of the nanostructure, there have been a number of studies on tunable nanofabrication and synthesis of noble metals. In this work, we will illustrate progress in engineering metallic nanostructures with various morphologies using versatile methods. We also discuss their SERS applications in different fields and the challenges.

  9. Semester-long inquiry-based molecular biology laboratory: Transcriptional regulation in yeast.

    Science.gov (United States)

    Oelkers, Peter M

    2017-03-04

    A single semester molecular biology laboratory has been developed in which students design and execute a project examining transcriptional regulation in Saccharomyces cerevisiae. Three weeks of planning are allocated to developing a hypothesis through literature searches and use of bioinformatics. Common experimental plans address a cell process and how three genes that encode for proteins involved in that process are transcriptionally regulated in response to changing environmental conditions. Planning includes designing oligonucleotides to amplify the putative promoters of the three genes of interest. After the PCR, each product is cloned proximal to β-galactosidase in a yeast reporter plasmid. Techniques used include agarose electrophoresis, extraction of DNA from agarose, plasmid purification from bacteria, restriction digestion, ligation, and bacterial transformation. This promoter/reporter plasmid is then transformed into yeast. Transformed yeast are cultured in conditions prescribed in the experimental design, lysed and β-galactosidase activity is measured. The course provides an independent research experience in a group setting. Notebooks are maintained on-line with regular feedback. Projects culminate with the presentation of a poster worth 60% of the grade. Over the last three years, about 65% of students met expectations for experimental design, data acquisition, and analysis. © 2016 by The International Union of Biochemistry and Molecular Biology, 45(2):145-151, 2017. © 2016 The International Union of Biochemistry and Molecular Biology.

  10. On the pedagogy of pharmacological communication: a study of final semester health science students.

    Science.gov (United States)

    Zetterqvist, Ann; Aronsson, Patrik; Hägg, Staffan; Kjellgren, Karin; Reis, Margareta; Tobin, Gunnar; Booth, Shirley

    2015-10-26

    There is a need to improve design in educational programmes for the health sciences in general and in pharmacology specifically. The objective of this study was to investigate and problematize pharmacological communication in educational programmes for the health sciences. An interview study was carried out where final semester students from programmes for the medical, nursing and specialist nursing in primary health care professions were asked to discuss the pharmacological aspects of two written case descriptions of the kind they would meet in their everyday work. The study focused on the communication they envisaged taking place on the concerns the patients were voicing, in terms of two features: how communication would take place and what would be the content of the communication. A phenomenographic research approach was used. The results are presented as outcome spaces, sets of categories that describe the variation of ways in which the students voiced their understanding of communication in the two case descriptions and showed the qualitatively distinct ways in which the features of communication were experienced. The results offer a base of understanding the students' perspectives on communication that they will take with them into their professional lives. We indicate that there is room for strengthening communication skills in the field of pharmacology, integrating them into programmes of education, by more widely implementing a problem-based, a case-oriented or role-playing pedagogy where final year students work across specialisations and there is a deliberate effort to evoke and assess advanced conceptions and skills.

  11. SERS-Active Nanoinjector for Intracellular Spectroscopy

    Science.gov (United States)

    Vitol, Elina; Orynbayeva, Zulfiya; Bouchard, Michael; Azizkhan-Clifford, Jane; Friedman, Gary; Gogotsi, Yury

    2009-03-01

    We developed a multifunctional nanopipette which allows simultaneous cell injection and intacellular surface-enhanced Raman spectroscopy (SERS) analysis. SERS spectra contain the characteristic frequencies of molecular bond vibrations. This is a unique method for studying cell biochemistry and physiology on a single organelle level. Unlike the fluorescence spectroscopy, it does not require any specific staining. The principle of SERS is based on very large electromagnetic field enhancement localized around a nano-rough metallic surface. Gold colloids are widely used SERS substrates. Previously, the colloidal nanoparticles were introduced into a cell by the mechanism of endocytosis. The disadvantage of this method is the uncontrollable aggregation and distribution of gold nanoparticles inside a cell which causes a significant uncertainty in the origin of the acquired data. At the same time, the nanoparticle uptake is irreversible. We present a SERS-active nanoinjector, coated with gold nanoparticles, which enables selective signal acquisition from any point-of-interest inside a cell. The nanoinjector provides a highly localized SERS signal with sub-nanometer resolution in real time.

  12. Office of Energy Research collaborative research programs administered by Oak Ridge Associated Universities: Annual report, FY 1987

    International Nuclear Information System (INIS)

    1988-02-01

    The US Department of Energy's (DOE) Office of Energy Research (OER) sponsors programs designed to encourage and support interaction between US colleges and universities and DOE research facilities. Faculty members, graduate students, undergraduates, and recent postgraduates participate in research and receive advanced training at DOE laboratories. Staff members from DOE laboratories visit campuses to deliver energy-related lectures and participate in seminars and classroom discussions. Oak Ridge Associated Universities (ORAU) has been involved in the developemnt and administration of these collaborative research programs since their inception. During FY 1987, ORAU administered appointments for the Office of Energy Research under the following two umbrella programs: University/DOE Laboratory Cooperative Program (Lab Co-op); Science and Engineering Research Semester (SERS). In addition, ORAU participated in a project to collect and assess information from individuals who had held research appointment as undergraduate students during a four-year period from 1979 to 1982. All of these activities are summarized in this report

  13. Conocer y ser en el paradigma constructivista

    Directory of Open Access Journals (Sweden)

    Jose Antonio Camargo Rodriguez

    2014-03-01

    Full Text Available Toda teoría acerca del aprendizaje se fundamenta en una interpretación del conocimiento, la cual se encuentra, a su vez, ligada a una cierta concepción de «ser». No será posible asimilar verdaderamente cualquiera de tales teorías si se ignoran, o no se consideran con el debido detenimiento, las ideas de conocer y «ser» que le sirven de base. Sc pone de presente que el constructivismo, en contraste con la teoría transmisionista de la enseñanza y el aprendizaje, predominante en la pedagogía tradicional, tiene su fundamento en la interpretación según la cual el conocer es una actividad humana en la que, a medida quo conoce, el hombre construye el «ser». Antes de todo conocimiento, las cosas no tienen un «ser»; están ahí, pero no se sabe lo que son. El «ser», quo constituye el objeto de todo conocer, aquello que el sujeto persigue a través de su conocimiento, no toes dada de antemano, ni le viene de fuera, sino quo es una elaboración quo el mismo realiza a través de su actividad cognoscitiva, un contenido de su propia conciencia. Hay, pues, una cierta paradoja entre las ideas de conocer y «ser» que sirven de fundamento al constructivismo, cuya reflexión se propone en aras de ganar una mejor comprensión, de encontrarle a este paradigma un sentido más allá de la pedagogía y la didáctica.

  14. Burn and earn: a randomized controlled trial incentivizing exercise during fall semester for college first-year students.

    Science.gov (United States)

    Pope, Lizzy; Harvey-Berino, Jean

    2013-03-01

    To examine the viability of monetary incentives to increase fitness-center use and maintain/improve the Body Mass Indexes (BMIs) of first-year students over the fall semester. Randomized-controlled trial with no-treatment and incentive conditions involving 117 first-year students. For 12 weeks, students in the incentive condition received monetary payments ranging from $10 to $38.75 for meeting researcher-set fitness-center use goals that were identical across conditions. Fitness-center use was monitored through electronic ID-card check-in and check-out records at the campus fitness center. 63% of incentive-condition participants met the weekly fitness-center use goals on average compared to only 13% of control-condition participants, a significant difference, pstudents meeting weekly fitness-center use goals. However, the increased fitness-center use by the incentive condition did not prevent an increase in BMI during fall semester. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Differences in Student Outcomes between Block, Semester, and Trimester Schedules.

    Science.gov (United States)

    McCreary, Jason; Hausman, Charles

    Despite the popularity of schedule modifications as a cost-effective reform to improve student outcomes, little empirical research on the consequences of alternative schedules has been conducted. The literature has been dominated by anecdotal reports. Even when empirical evidence is examined, causal comparisons of school outcomes between schedules…

  16. PENINGKATAN KETERAMPILAN BERBICARA BAHASA INGGRIS DENGAN METODE SUGGESTOPEDIA PADA MAHASISWA SEMESTER II-E TBI STAIN PAMEKASAN

    Directory of Open Access Journals (Sweden)

    Sumihatul Ummah

    2015-11-01

    Full Text Available There are two problems in the result of research that will be discussed in this article. They are (1 how are the steps of the implementation of suggestopedia method in learning speaking English at the second semester students of E class TBI STAIN Pamekasan and (2 How are the increasing of speaking English skill for the second semester students of E class TBI STAIN Pamekasan in learning speaking English by using the suggestopedia method. The research method is classroom action research by using research strategy of Kemmis and Mc Taggert Model which consist of four (4 steps, namely planning, acting, observing, and reflecting. The result of research provided that classically for the 1st, 2nd, and 3rd cycle indicated the increasing of students learning completeness scores, each of them are 38.23%, 67.54%, and 82.35%. While the students performance for each aspects are increasing from the 1st cycle up to 3rd cycle. The students performance of speaking English activities in the classroom from each aspects that more appear was grammar with score 85.2%. for the 2nd cycle was comprehensibility with score 88.2% and vocabulary with score 88.2%, and for the 3rd  cycle that more appear was fluency with score 91.2%.  Besides, for the frequency percentage of students performance from each cycles are more increasing, by the 1st  cycle 55% (enough, the 2nd cycle 70% (good, and the 3rd cycle 85% (very good. Finally, the suggestopedia method in learning speaking English can increase the result of students learning. In fact, the students look like be enthusiastic in learning speaking English. The students were active to joint with this subject from each cycle. By the good atmosphere, conducive situation of the classroom, and soft music made the students to be relax in learning the subject. It also was increase imagination, concentration, and liveliness for the students.

  17. and Au nanoparticles for SERS applications

    Directory of Open Access Journals (Sweden)

    Fazio Enza

    2018-01-01

    Full Text Available The morphological and optical properties of noble metal nanoparticles prepared by picosecond laser generated plasmas in water were investigated. First, the ablation efficiency was maximized searching the optimal focusing conditions. The nanoparticle size, measured by Scanning Transmission Electron Microscopy, strongly depends on the laser fluence, keeping fixed the other deposition parameters such as the target to scanner objective distance and laser repetition frequency. STEM images indicate narrow gradients of NP sizes. Hence the optimization of ablation parameters favours a fine tuning of nanoparticles. UV-Visible spectroscopy helped to determine the appropriate laser wavelength to resonantly excite the localized surface plasmon to carry out Surface Enhanced Raman Scattering (SERS measurements. The SERS activity of Ag and Au substrates, obtained spraying the colloids synthesized in water, was tested using crystal violet as a probe molecule. The good SERS performance, observed at excitation wavelength 785 nm, is attributed to aggregation phenomena of nanoparticles sprayed on the support.

  18. The frequency of genotypes for the SNP Ser/Ser in the studied population of Albanian women is higher in the Balkan region

    Directory of Open Access Journals (Sweden)

    Zafer Gashi

    2016-08-01

    Full Text Available In women undergoing natural cycles, just one oocyte is usually selected for ovulation, yet routine clinical techniques to support the development of multiple follicles using additional gonadotrophins result in numerous ovulations. Several parameters have been postulated as predictors of ovarian response (inhibin B, 17-β-estradiol and antiMüllerian hormone. Nevertheless, the FSH level on the day 3 of menstrual cycle remains, the most widely used biomarker due to its low cost, although, the genetic background of individuals seems to determine the response of patients to rFSH stimulation better than the stimulation design. Consequently, the variants of FSHR were explored and they may be involved in the role of FSH receptor in mediated signal transduction and with ovarian response in infertile women submitted to ovarian stimulation. In this study we examined, for the first time, the prevalence of genotype variants Asn680Ser in population Albanian women from Kosovo Dukagjin region who took part in IVF / ICSI program. The frequencies of the Asn680Ser genotype variants were as follows: Asn/Asn 22.1%, Asn/Ser 47.1%, and Ser/Ser 30.8%, respectively (Table 1. bE2 levels between the three genotype variants showed slight but statistically significant difference (p= 0.0308. No difference was also found between the genotype groups either in terms of AFC, amount of the FSH required for ovulation induction, stimulation length days, number of dominant follicles, oocyte retrieval number or endometrial thickness (Table 2. BMI was significantly higher in the Ser/Ser group as compared to those from the Asn/Ser or the Asn/Asn group (p= 0.0010 (Table 2. In the study population of Albanian women Dukagjin region of Kosovo had a higher incidence of Ser / SER genotype compared to Asn / Asn genotype. Our research results in the Albanian population differ from published data for other ethnic groups in the Balkans.

  19. Acerca de tres dimensiones del ser humano

    OpenAIRE

    Fúnez, Rubén

    2007-01-01

    El autor resume las ideas importantes del libro "Tres dimensiones del ser humano", se pregunta por la importancia del planteamiento zubiriano, tanto para la historia de la filosofía, como para la situación que actualmente nos ha tocado vivir.

  20. Organising and learning experiences of the first semester MA Program ePedagogy / Visual Knowledge Building

    NARCIS (Netherlands)

    Jaap Jansen

    2006-01-01

    This paper will discuss the process of the MA program ePedagogy / Visual Knowledge Building during the first semester of the academic year 2005 – 2006. This MA program is a joint venture between the Universities of Helsinki, Hamburg and INHOLLAND. This publication will discuss and evaluate the

  1. Impact of One-Semester Outdoor Education Programs on Adolescent Perceptions of Self-Authorship

    Science.gov (United States)

    McGowan, Amanda L.

    2016-01-01

    This study investigated one-semester outdoor education program impact on adolescents' perceived self-authorship--the ability to form our identity independently from the expectations of external individuals and the capacity to invent our beliefs, identity, and relationships (Baxter Magolda, 1998; Kegan, 1982)--as measured by the Self-Authorship…

  2. Can Earth Materials BE Adequately Covered in a - or Two-Semester Course?

    Science.gov (United States)

    Hefferan, K. P.; O'Brien, J.

    2007-12-01

    Traditional geology programs offer courses in mineralogy, optical mineralogy, igneous petrology, metamorphic petrology, sedimentology and economic geology. At many universities this suite of mineralogy/petrology courses has been supplanted by a one-semester or two-semester Earth Materials course. This interactive poster poses five questions to faculty and students related to the means by which Earth Materials can be delivered: 1) Available online syllabi demonstrate a wide variation in the topics addressed in Earth Materials courses; is there a standard core of key topics that must be covered and in what level of detail? 2) Can a one-semester or two- semester Earth Materials course adequately cover these topics? 3) Excellent textbooks exist in both mineralogy and in petrology; what textbooks, if any, adequately encompass Earth Materials? 4) How has the online environment changed the way in which we use textbooks in the classroom? 5) Given the evolution of geology programs, higher education and the global economy in the past twenty years, what additional changes can be anticipated with respect to delivery and demand of Earth Materials topics? Answers-- or at least related discussions-- to these questions are encouraged via verbal dialogue among participants and/or by comments written on the poster. Our goal is to solicit faculty, student and industry feedback to create a textbook, curricula and online materials that support an Earth Materials course.

  3. Learning to Argue with Intermediate Macro Theory: A Semester-Long Team Writing Project

    Science.gov (United States)

    Strasser, Georg; Wolfe, Marketa Halova

    2014-01-01

    The authors describe their experience with integrating a semester-long economic analysis project into an intermediate macroeconomic theory course. Students work in teams of "economic advisors" to write a series of nested reports that analyze the current state of the economy, and propose and evaluate policies for a decision-maker. The…

  4. Self-Assessment and Reflection in a 1st Semester Course for Software Engineering Students

    Science.gov (United States)

    Nielsen, Jacob; Majgaard, Gunver; Sørensen, Erik

    2013-01-01

    How can student self-assessment be used as a tool and become beneficial for both lecturers and students? We used a simple self-assessment tool for pre- and post-testing on a first-semester engineering course. The students graded their knowledge on human-computer interaction based on their ability to understand and explain specific concepts. The…

  5. Socializing the European Semester? Economic governance and social policy coordination in Europe 2020

    NARCIS (Netherlands)

    Zeitlin, J.; Vanhercke, B.

    2014-01-01

    The European Semester of policy coordination, which is the core of EU’s new institutional architecture for economic and social governance, introduced since the beginning of the Euro crisis, has prompted questions about the nature and dynamics of the EU’s emerging socio-economic governance

  6. The Development and Nature of Problem-Solving among First-Semester Calculus Students

    Science.gov (United States)

    Dawkins, Paul Christian; Epperson, James A. Mendoza

    2014-01-01

    This study investigates interactions between calculus learning and problem-solving in the context of two first-semester undergraduate calculus courses in the USA. We assessed students' problem-solving abilities in a common US calculus course design that included traditional lecture and assessment with problem-solving-oriented labs. We investigate…

  7. Beyond the Tourist Gaze? Cultural Learning on an American "Semester Abroad" Programme in London

    Science.gov (United States)

    Janes, Dominic

    2008-01-01

    Is the short-term study abroad experience, particularly when undertaken with a self-contained group of international students such as on a "semester abroad programme" accredited by a US university, little more than glorified tourism? This study investigates some of the ways in which a group of American students developed their…

  8. Developments during the first semester 2001; Les developpements au premier semestre 2001

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This document gives a panorama of the nuclear energy situation at the end of the first 2001 semester. The energy policy concerning the nuclear industry development, is discussed for many countries: USA, Germany, United Kingdom, Japan, China, India, Korea, Taiwan, Africa and south America, Russia and east Europe. (A.L.B.)

  9. Design and Evaluation of a One-Semester General Chemistry Course for Undergraduate Life Science Majors

    Science.gov (United States)

    Schnoebelen, Carly; Towns, Marcy H.; Chmielewski, Jean; Hrycyna, Christine A.

    2018-01-01

    The chemistry curriculum for undergraduate life science majors at Purdue University has been transformed to better meet the needs of this student population and prepare them for future success. The curriculum, called the 1-2-1 curriculum, includes four consecutive and integrated semesters of instruction in general chemistry, organic chemistry, and…

  10. Chemical Structure and Properties: A Modified Atoms-First, One-Semester Introductory Chemistry Course

    Science.gov (United States)

    Schaller, Chris P.; Graham, Kate J.; Johnson, Brian J.; Jakubowski, Henry V.; McKenna, Anna G.; McIntee, Edward J.; Jones, T. Nicholas; Fazal, M. A.; Peterson, Alicia A.

    2015-01-01

    A one-semester, introductory chemistry course is described that develops a primarily qualitative understanding of structure-property relationships. Starting from an atoms-first approach, the course examines the properties and three-dimensional structure of metallic and ionic solids before expanding into a thorough investigation of molecules. In…

  11. Teaching Green and Sustainable Chemistry: A Revised One-Semester Course Based on Inspirations and Challenges

    Science.gov (United States)

    Marteel-Parrish, Anne E.

    2014-01-01

    An elective course, "Toward the Greening of Our Minds": Green and Sustainable Chemistry, has been offered at Washington College since 2005. This new course without laboratory is designed for chemistry and biology majors and minors who have previously taken two semesters of general chemistry and organic chemistry. Due to the popularity of…

  12. Motivation, Academic Assessments and First-Semester Success at a Midwestern Technical College

    Science.gov (United States)

    Dillon, Sarah A.

    2017-01-01

    This study examined college admission criteria and college readiness in an effort to reduce barriers in college admission. The Academic Motivation Scale (AMS) was administered to a convenience sample of 74 participants among 503 students during their first semester at a two-year college. Scale scores were compared to demographic characteristics,…

  13. Academic literacy diagnostic assessment in the first semester of first year at university

    Directory of Open Access Journals (Sweden)

    Lorinda Palmer

    2014-03-01

    Full Text Available One vital aspect of the first semester of the first year at university is how academic literacy expectations are made explicit though teaching and assessment practices at the disciplinary level. This paper describes how an academic literacy diagnostic process, and the MASUS tool, was used to ascertain the academic literacy profile of a cohort of undergraduate nursing students [N=569] at the beginning and end of their first semester. Key findings of this quantitative descriptive case study were that only just over half of commencing students possessed appropriate academic literacy skills in all four aspects of the diagnostic and nearly 20% scored in the lowest band—suggesting difficulty with multiple aspects of academic literacy. By the end of semester, 77% of the students who had scored in the lowest band of the MASUS at the beginning of the semester had improved their scores to the middle or highest band, and 73% of them eventually attained a pass or higher grade for the course. The findings of this study suggest that large-scale academic literacy diagnostic assessment, when embedded and contextualized within a course of study, is an effective means of providing the early feedback and targeted support that many commencing university students need.

  14. Team-Based Learning Reduces Attrition in a First-Semester General Chemistry Course

    Science.gov (United States)

    Comeford, Lorrie

    2016-01-01

    Team-based learning (TBL) is an instructional method that has been shown to reduce attrition and increase student learning in a number of disciplines. TBL was implemented in a first-semester general chemistry course, and its effect on attrition was assessed. Attrition from sections before implementing TBL (fall 2008 to fall 2009) was compared with…

  15. Increasing First-Semester Student Engagement: A Residential Community Retention Study

    Science.gov (United States)

    Briggs, Ronald

    2012-01-01

    The purpose of this study was to increase first year residential student engagement and participation in residence hall programs during the 2011 fall semester at the Downtown Phoenix Campus of Arizona State University. Six upperclassmen (Taylor Place Leaders) residing in a residence hall (Taylor Place) were matched by academic major with 17 first…

  16. Semester-Long Inquiry-Based Molecular Biology Laboratory: Transcriptional Regulation in Yeast

    Science.gov (United States)

    Oelkers, Peter M.

    2017-01-01

    A single semester molecular biology laboratory has been developed in which students design and execute a project examining transcriptional regulation in "Saccharomyces cerevisiae." Three weeks of planning are allocated to developing a hypothesis through literature searches and use of bioinformatics. Common experimental plans address a…

  17. Computer-Mediated Communication with Distant Friends: Relations with Adjustment during Students' First Semester in College

    Science.gov (United States)

    Ranney, John D.; Troop-Gordon, Wendy

    2012-01-01

    Because of recent technological innovations, college freshmen can readily communicate with friends who they see infrequently (e.g., friends from home). The current study addressed whether computer-mediated communication with these distant friends can compensate for a lack of high-quality on-campus friendships during students' first semester of…

  18. Social Modeling Influences and Alcohol Consumption during the First Semester of College: A Natural History Study

    Science.gov (United States)

    Talbott, Laura L.; Moore, Charity G.; Usdan, Stuart L.

    2012-01-01

    The authors examine both the alcohol consumption pattern of freshmen students during their first semester and the degree to which social modeling of peer behavior impacts consumption. A total of 534 students, residing on campus, were prospectively examined at four 30-day intervals. Data were evaluated on the basis of age, gender, and the effects…

  19. Principles of Marketing. A One-Semester Cluster Course for Marketing Education. Curriculum Guide.

    Science.gov (United States)

    Cockrum, Jim

    This curriculum guide was developed to help teachers use the new textbook adopted by Texas in 1991-92 for teaching the 1-semester Principles of Marketing course. The guide is organized in four sections. The first section contains information on using the curriculum guide, including an overview, sample lesson plans and other worksheets, suggestions…

  20. Graphene-Plasmonic Hybrid Platform for Label-Free SERS Biomedical Detection

    Science.gov (United States)

    Wang, Pu

    Surface Enhanced Raman Scattering (SERS) has attracted explosive interest for the wealth of vibrational information it provides with minimal invasive effects to target analyte. Nanotechnology, especially in the form of noble metal nanoparticles exhibit unique electromagnetic and chemical characteristics that are explored to realize ultra-sensitive SERS detection in chemical and biological analysis. Graphene, atom-thick carbon monolayer, exhibits superior chemical stability and bio-compatibility. A combination of SERS-active metal nanostructures and graphene will create various synergies in SERS. The main objective of this research was to exploit the applications of the graphene-Au tip hybrid platform in SERS. The hybrid platform consists of a periodic Au nano-pyramid substrate to provide reproducible plasmonic enhancement, and the superimposed monolayer graphene sheet, serving as "built-in" Raman marker. Extensive theoretical and experimental studies were conducted to determine the potentials of the hybrid platform as SERS substrate. Results from both Finite-Domain Time-Domain (FDTD) numerical simulation and Raman scattering of graphene suggested that the hybrid platform boosted a high density of hotspots yielding 1000 times SERS enhancement of graphene bands. Ultra-high sensitivity of the hybrid platform was demonstrated by bio-molecules including dye, protein and neurotransmitters. Dopamine and serotonin can be detected and distinguished at 10-9 M concentration in the presence of human body fluid. Single molecule detection was obtained using a bi-analyte technique. Graphene supported a vibration mode dependent SERS chemical enhancement of ˜10 to the analyte. Quantitative evaluation of hotspots was presented using spatially resolved Raman mapping of graphene SERS enhancement. Graphene plays a crucial role in quantifying SERS hotspots and paves the path for defining SERS EF that could be universally applied to various SERS systems. A reproducible and statistically

  1. Meanings for Sex and Commitment Among First Semester College Men and Women: A Mixed-Methods Analysis.

    Science.gov (United States)

    Olmstead, Spencer B; Anders, Kristin M; Conrad, Kathryn A

    2017-08-01

    The purpose of this study was to replicate and extend research on the meanings for sex and commitment using a sample of first semester college students (N = 268). We examined responses to a series of open-ended questions about participants' meanings for sex and how they described these meanings as connected with relationship commitment. Our qualitative analyses replicated those of Olmstead, Billen, Conrad, Pasley, and Fincham (2013). Our largest group was the Committers (sex is indicative of love and trust and occurs after commitment is developed in a relationship), followed by Flexibles (sex can hold deep personal meaning, but can also be purely for pleasure and isn't always connected with commitment), and then Recreationers (sex is a basic need or purely for pleasure and is not associated with commitment). Groups were then examined based on demographic characteristics and pre-college hookup experience. Groups were found to differ by gender, relationship status and type, religiosity, and pre-college hookup experience. For example, a greater proportion of women than men were in the Committers group, whereas a greater proportion of men than women were in the Flexibles and Recreationers groups. Those in the Committers group had fewer pre-college hookup partners than Flexibles and Recreationers; however, Flexibles and Recreationers did not differ in number of pre-college hookup partners. We then followed up (at the end of the semester) with a subsample (n = 73) of participants to examine whether meanings for sex and commitment remained stable or changed over a brief period of time. The majority (82.2 %) of participants' meanings remained stable. For those whose meanings shifted, meanings became more consistent with those of the Committers group than the other two groups. Implications for research and sexual and relationship education are discussed.

  2. Research

    African Journals Online (AJOL)

    2016-05-16

    May 16, 2016 ... and addresses deficiencies in students' learning and other generic skills. .... theme; and change from end-of-semester to continuous assessment in .... in experience was also driven by a continuous process of formative and.

  3. A study of depression and anxiety, general health, and academic performance in three cohorts of veterinary medical students across the first three semesters of veterinary school.

    Science.gov (United States)

    Reisbig, Allison M J; Danielson, Jared A; Wu, Tsui-Feng; Hafen, McArthur; Krienert, Ashley; Girard, Destiny; Garlock, Jessica

    2012-01-01

    This study builds on previous research on predictors of depression and anxiety in veterinary medical students and reports data on three veterinary cohorts from two universities through their first three semesters of study. Across all three semesters, 49%, 65%, and 69% of the participants reported depression levels at or above the clinical cut-off, suggesting a remarkably high percentage of students experiencing significant levels of depression symptoms. Further, this study investigated the relationship between common stressors experienced by veterinary students and mental health, general health, and academic performance. A factor analysis revealed four factors among stressors common to veterinary students: academic stress, transitional stress, family-health stress, and relationship stress. The results indicated that both academic stress and transitional stress had a robust impact on veterinary medical students' well-being during their first three semesters of study. As well, academic stress negatively impacted students in the areas of depression and anxiety symptoms, life satisfaction, general health, perception of academic performance, and grade point average (GPA). Transitional stress predicted increased depression and anxiety symptoms and decreased life satisfaction. This study helped to further illuminate the magnitude of the problem of depression and anxiety symptoms in veterinary medical students and identified factors most predictive of poor outcomes in the areas of mental health, general health, and academic performance. The discussion provides recommendations for considering structural changes to veterinary educational curricula to reduce the magnitude of academic stressors. Concurrently, recommendations are suggested for mental health interventions to help increase students' resistance to environmental stressors.

  4. Gender disparities in second-semester college physics: The incremental effects of a “smog of bias”

    Directory of Open Access Journals (Sweden)

    Lauren E. Kost-Smith

    2010-09-01

    Full Text Available Our previous research [Kost et al., Phys. Rev. ST Phys. Educ. Res. 5, 010101 (2009] examined gender differences in the first-semester, introductory physics class at the University of Colorado at Boulder. We found that: (1 there were gender differences in several aspects of the course, including conceptual survey performance, (2 these differences persisted despite the use of interactive engagement techniques, and (3 the post-test gender differences could largely be attributed to differences in males’ and females’ prior physics and math performance and their incoming attitudes and beliefs. In the current study, we continue to characterize gender differences in our physics courses by examining the second-semester, electricity and magnetism course. We analyze three factors: student retention from Physics 1 to Physics 2, student performance, and students’ attitudes and beliefs about physics, and find gender differences in all three of these areas. Specifically, females are less likely to stay in the physics major than males. Despite males and females performing about equally on the conceptual pretest, we find that females score about 6 percentage points lower than males on the conceptual post-test. In most semesters, females outperform males on homework and participation, and males outperform females on exams, resulting in course grades of males and females that are not significantly different. In terms of students’ attitudes and beliefs, we find that both males and females shift toward less expertlike beliefs over the course of Physics 2. Shifts are statistically equal for all categories except for the Personal Interest category, where females have more negative shifts than males. A large fraction of the conceptual post-test gender gap (up to 60% can be accounted for by differences in males’ and females’ prior physics and math performance and their pre-Physics 2 attitudes and beliefs. Taken together, the results of this study suggest

  5. A study of the effectiveness of a four semester preservice Secondary Science Teacher Education program regarding changes in teacher perceptions and practices

    Science.gov (United States)

    Yakar, Zeha

    The purpose of this study was to investigate the development and change in constructivist behaviors of preservice science teachers of the Iowa-Secondary Science Teacher Education Program (SSTEP) over the four semester sequence. Constructivist behaviors were investigated from four perspectives; including actual classroom performances as viewed from videotapes, teacher perceptions of teacher use of constructivist teaching practices, and teacher beliefs as gained from open-ended questions, and written artifacts. The participants of the study included a total of 41 secondary science preservice teachers in four different semesters of their teacher preparation program. Three instruments were used to generate the main data to answer the research questions. The three instruments were: (1) Constructivist Learning Environment Survey (CLES), (2) Philosophy of Teaching and Learning (PTL), and (3) videotape portfolio evaluated with the Reformed Teaching Observation Protocol (RTOP). Major findings include the following: (1) Preservice teachers' perceptions regarding constructivist approaches become significantly and increasingly more student-centered in terms of Personal Relevance, Critical Voice, Shared Control, and Student Negotiation as they prepare through the four semester sequence. (2) Preservice teachers' conceptions concerning teaching and learning become significantly and increasingly more student-centered in terms of what students need to do to improve their understanding of science concepts. (3) Preservice teachers conceptions and their perceptions about actual classroom practices rarely align with observed teaching practices in their classrooms. Although preservice teachers hold student-centered beliefs and perceptions, their actual classroom teaching practices were "transitional constructivist". (4) Preservice teachers' constructivist practices of teaching and learning began to decline in the third semester with preservice teachers moving towards more teacher

  6. Electrodeposited Silver Nanoparticles Patterned Hexagonally for SERS

    International Nuclear Information System (INIS)

    Gu, Geun Hoi; Lee, Sue Yeone; Suh, Jung Sang

    2010-01-01

    We have fabricated hexagonally patterned silver nanoparticles for surface-enhanced Raman scattering (SERS) by electrodepositing silver on the surface of an aluminum plate prepared by completely removing the oxide from anodic aluminum oxide (AAO) templates. Even after completely removing the oxide, well-ordered hexagonal patterns, similar to the shape of graphene, remained on the surface of the aluminum plate. The borders of the hexagonal pattern protruded up to form sorts of nano-mountains at both the sides and apexes of the hexagon, with the apexes protruding even more significantly than the sides. The aluminum plate prepared by completely removing the oxide has been used in the preparation of SERS substrates by sputter-coating of gold or silver on it. Instead of sputter-coating, here we have electro-deposited silver on the aluminum plate. When silver was electro-deposited on the plate, silver nanoparticles were made along the hexagonal margins.

  7. Flexible SERS Substrates: Challenges and Opportunities

    Science.gov (United States)

    2016-01-28

    are still widely used due to the ease with which silver and gold nanoparticles can be produced. Nanoparticle inks are colloidal suspensions of...interactions between the analyte, silver nanoparticles, and a salt. This system has also been applied to detection of trace antibiotics for food safety...Cleanable SERS Substrates Based on Silver Nanoparticle Decorated Electrospun Nano-fibrous Membranes Chaoyang Jiang Porous electrospun nanofibrous

  8. Criatividade em ação: ser criativo é ser criança

    Directory of Open Access Journals (Sweden)

    Antonio Mendes Silva Filho

    2012-11-01

    Full Text Available Todo ser humano é criativo e isso decorre da capacidade de imaginação. Essa capacidade é acentuada quando você tem a possibilidade de explorar e a curiosidade aguçada. Não exemplo melhor do que uma criança. Ser criativo é ser criança. Esta capacidade alcança o ápice quando se busca criar como criança fazendo uso de sagacidade, persistência, desorganização e com a possibilidade de errar. Isso é explorar e experimentar, deixando o cérebro livre e sem pressão, agindo despreocupadamente em determinado período de tempo. Nesse sentido, este artigo explora a importancia dar oportunidade do ser humano explorar sua capacidade de criar via imaginação

  9. Development of SERS active fibre sensors

    International Nuclear Information System (INIS)

    Polwart, Ewan

    2002-01-01

    Surface-enhanced Raman scattering (SERS) is sensitive and selective and when coupled with fibre-optics could potentially produce an effective chemical sensing system. This thesis concerns the development of a single-fibre-based sensor, with an integral SERS-active substrate. A number of different methods for the manufacture of SERS-active surfaces on glass substrates were investigated and compared. The immobilisation of metal nanoparticles on glass functionalised with (3-aminopropyl)trimethoxysilane emerged as a suitable approach for the production of sensors. Substrates prepared by this approach were characterised using UV-visible spectroscopy, electron microscopy and Raman mapping. It was found that exposure of substrates to laser radiation led to a decrease in the signal recorded from adsorbed analytes. This speed of the decrease was shown to depend on the analyte, and the exciting wavelength and power. SERS-active fibre sensors were produced by immobilisation of silver nanoparticles at the distal end of a (3-aminopropyl)trimethoxysilane-derivatised optical fibre. These sensors were used to obtain spectra with good signal to noise ratios from 4-(benzotriazol-5-ylazo)-3,5-dimethoxyphenylamine and crystal violet. Sensing of dyes in effluent was also investigated. The development of sensors for the measurement of pH, by treating the SERS-active fibre tip with pH sensitive dyes is also described. Spectral changes were observed with these sensors as a response to the pH. Partial least squares regression was used to produce linear calibration models for the pH range 5-11 from which it was possible to predict the pH with an accuracy of ∼0.2 pH units. Some of the limitations of these sensors were explored. The feasibility of using these sensors for measurement of oxygen and thiols, was investigated. The measurement of oxygen using methylene blue as a transducer was demonstrated. Two transduction methodologies--reactions with iron porphyrins and pyrrole-2,5-diones

  10. El Segundo Cerebro del ser humano.

    OpenAIRE

    Rocío Ponce

    2015-01-01

    Existen dos tipos de cerebros, el conocido por todos formado por el sistema nervioso central, que sería el cerebro donde las emociones se forman en base a las experiencias anteriores. El segundo cerebro, el otro, ignorado por la mayoría de seres humanos es el cerebro que está en los intestinos, Sistema Nervioso Enteral o mesentérico, que se caracteriza por la relación del cerebro y aparato digestivo, este cerebro posee más neuronas que su par, guarda emociones, determina la respuesta de acuer...

  11. EL SER HUMANO COMO CONSUMIDOR: APLICACIÓN A INVESTIGACIÓN DE MERCADO DE GUAYABA EN EL DEPARTAMENTO DEL ATLÁNTICO - THE HUMAN BEING AS A CONSUMER: APPLICATION TO MARKETING RESEARCH OF GUAVA IN THE DEPARTAMENTO OF ATLANTICO

    Directory of Open Access Journals (Sweden)

    HILDA ESTRADA LÓPEZ

    2010-06-01

    Full Text Available From the consumer’s perspective, this article shows the results of two marketing researches which take part in a project funded by private and public companies to support small enterprises. For the former, 127 surveys were made to people responsible for shopping at hotels, grocery stores and other grocery dealers. For the latter, 64 final customers were surveyed. The information gathered was used to evaluate the way consumers receive the products made by the manufacturer and trading company, Profrutal, located in Palmar de Varela, Atlantico; this fact gave rise to a marketing plan. The process presented may be an example to stimulate managerial abilities of other small artisanal companies, thus increasing its capacity to create new employment opportunities.ResumenEste artículo presenta, desde la perspectiva del consumidor, los resultados de dos investigaciones de mercado y hacen parte de un proyecto financiado por entidades privadas y públicas para apoyar a la microempresa. Para la primera, se hicieron 127 encuestas a losresponsables de las compras en hoteles, tiendas de barrio y otros distribuidores. Para la segunda, se tomaron 64 compradores finales. La información recopilada permitió evaluar la forma como los consumidores perciben los productos elaborados por la empresa procesadora y comercializadora de frutas Profrutal, ubicada en Palmar de Varela, Atlántico, lo que dio origen a un plan de mercadeo. El proceso presentado puede servir de ejemplo para otras microempresas artesanales al incrementar su capacidad de gestión y, en consecuencia, su potencial de generación de empleo.

  12. On the chemical enhancement in SERS

    Science.gov (United States)

    Jensen, Lasse

    2012-12-01

    In Surface-enhanced Raman scattering (SERS), the Raman signal of a molecule adsorbed on a metal surface is enhanced by many orders of magnitude. This provides a "finger-print" of molecules which can be used in ultrasensitive sensing devises. Here we present a time-dependent density functional theory (TDDFT) study of the molecule-surface chemical coupling in SERS. A systematic study of the chemical enhancement (CHEM) of meta-and para-substituted pyridines interacting with a small silver cluster (Ag20) is presented. We find that the magnitude of chemical enhancement is governed to a large extent by the energy difference between the highest occupied energy level (HOMO) of the metal and the lowest unoccupied energy level (LUMO) of the molecule. A two-state approximation shows that the enhancement scales roughly as (ωX/ω¯e)4, where accent="true">ω¯e is an average excitation energy between the HOMO of the metal and the LUMO of the molecule and wX the HOMO-LUMO gap of the free molecule. Furthermore, we demonstrate that it is possible to control the CHEM enhancement by switching a dithienylethene photoswitch from its closed form to its open form. The open form of the photoswitch is found to be the strongest Raman scatterer when adsorbed on the surface whereas the opposite is found for the free molecule. This trend is explained using the simple two-state approximation.

  13. Optimalisasi Prestasi Belajar Materi Elektromagnet dengan Menggunakan Pendekatan Eksperimen dalam Pembelajaran IPA pada Peserta Didik Kelas IX A SMP Negeri 3 Teras Semester Gasal Kabupaten Boyolali Tahun Pelajaran 2011/2012

    OpenAIRE

    Budiharjo Budiharjo

    2015-01-01

    This research purpose is to describe about effort to increase learning achievement giving task autonomous structure in learning electromagnet material of the student’s class IX A SMP Negeri 3 Teras Boyolali regency semester 2011/2012. Subject and data source of the research the students class IX A sum 40 students. Collecting data method uses observation, documentation and test. Analysis data uses critic and comparative. Reaching indicator uses KKM 63 and complete target 100%. Research procedu...

  14. Jmol-Enhanced Biochemistry Research Projects

    Science.gov (United States)

    Saderholm, Matthew; Reynolds, Anthony

    2011-01-01

    We developed a protein research project for a one-semester biochemistry lecture class to enhance learning and more effectively train students to understand protein structure and function. During this semester-long process, students select a protein with known structure and then research its structure, sequence, and function. This project…

  15. SERS internship Spring 1995 abstracts and research papers

    Energy Technology Data Exchange (ETDEWEB)

    Davis, B.

    1995-11-01

    Presented topics varied over many fields in science and engineering. Botany on grasses in California, real time face recognition technology, thermogravimetric studies on corrosion and finite element modeling of the human pelvis are examples of discussed subjects. Further fields of study are carcinogenics, waste management, radar imaging, automobile accessories, document searching on the internet, and shooting stars. Individual papers are indexed separately on EDB.

  16. Assessment of burnout in veterinary medical students using the Maslach Burnout Inventory-Educational Survey: a survey during two semesters.

    Science.gov (United States)

    Chigerwe, Munashe; Boudreaux, Karen A; Ilkiw, Jan E

    2014-11-28

    Burnout among veterinary students can result from known stressors in the absence of a support system. The objectives of this study were to evaluate use of the Maslach Burnout Inventory-Educator Survey (MBI-ES) to assess burnout in veterinary students and evaluate the factors that predict the MBI-ES scores. The MBI-ES was administered to first (Class of 2016) and second year (Class of 2015) veterinary medical students during the 2012-2013 academic year in the fall and spring semesters. Factor analysis and test reliability for the survey were determined. Mean scores for the subscales determining burnout namely emotional exhaustion (EE), depersonalization (DP) and lack of personal accomplishment (PA) were calculated for both classes in the 2 semesters. Multiple regression analysis was performed to evaluate other factors that predict the MBI-ES scores. A non-probability sampling method was implemented consisting of a voluntary sample of 170 and 123 students in the fall and spring semesters, respectively. Scores for EE, DP and PA were not different between the 2 classes within the same semester. Mean ± SD scores for EE, DP and PA for the fall semester were 22.9 ± 9.6, 5.0 ± 4.8 and 32.3 ± 6.7, respectively. Mean ± SD scores for EE, DP and PA the spring semester were 27.8 ± 10.7, 6.5 ± 6.1and 31.7 ± 6.8, respectively. The EE score was higher in spring compared to fall while DP and PA scores were not different between the 2 semesters. Living arrangements specifically as to whether or not a student lived with another veterinary medical students was the only variable significantly associated with the MBI-ES scores. Students in this study had moderate levels of burnout based on the MBI-ES scores. The MBI-ES was an acceptable instrument for assessing burnout in veterinary medical students. The EE scores were higher in the spring semester as compared to the fall semester. Thus students in the first and second years of veterinary school under the current curriculum

  17. Ser lo mismo, ser diferente: contra la masificación

    OpenAIRE

    Saldarriaga Roa, Alberto

    2005-01-01

    La sociedad moderna se ha configurado, en los dos últimos siglos, como una sociedad de masas. Esto parece ser una condición sine qua non de su estructura y operatividad. La masificación se manifiesta no sólo en el comportamiento social sino también en el

  18. SERS detection of biomolecules using lithographed nanoparticles towards a reproducible SERS biosensor

    Energy Technology Data Exchange (ETDEWEB)

    David, Catalina; Guillot, Nicolas; Chapelle, Marc Lamy de la [Laboratoire CSPBAT (FRE 3043), UFR SMBH, Universite Paris XIII, 74 rue Marcel Cachin, F-93017 Bobigny (France); Shen, Hong; Toury, Timothee, E-mail: marc.lamydelachapelle@univ-paris13.fr [ICD-LNIO-UMR, CNRS 6279, Universite de technologie de Troyes, 12 rue Marie Curie, F-10010 Troyes (France)

    2010-11-26

    In this paper we highlight the accurate spectral detection of bovine serum albumin and ribonuclease-A using a surface-enhanced Raman scattering (SERS) substrate based on gold nanocylinders obtained by electron-beam lithography (EBL). The nanocylinders have diameters from 100 to 180 nm with a gap of 200 nm. We demonstrate that optimizing the size and the shape of the lithographed gold nanocylinders, we can obtain SERS spectra of proteins at low concentration. This SERS study enabled us to estimate high enhancement factors (10{sup 5} for BSA and 10{sup 7} for RNase-A) of important bands in the protein Raman spectrum measured for 1 mM concentration. We demonstrate that, to reach the highest enhancement, it is necessary to optimize the SERS signal and that the main parameter of optimization is the LSPR position. The LSPR have to be suitably located between the laser excitation wavelength, which is 632.8 nm, and the position of the considered Raman band. Our study underlines the efficiency of gold nanocylinder arrays in the spectral detection of proteins.

  19. Stabilization of alanine substituted p53 protein at Ser15, Thr18, and Ser20 in response to ionizing radiation

    International Nuclear Information System (INIS)

    Yamauchi, Motohiro; Suzuki, Keiji; Kodama, Seiji; Watanabe, Masami

    2004-01-01

    Phosphorylation of p53 at Ser15, Thr18, and Ser20 has been thought to be important for p53 stabilization in response to ionizing radiation. In the present study, we examined the X-ray-induced stabilization of Ala-substituted p53 protein at Ser15, Thr18, and Ser20, whose gene expression was controlled under an ecdyson-inducible promoter. We found that all single-, double-, or triple-Ala-substituted p53 at Ser15, Yhr18, and Ser20 were accumulated in the nucleus similarly to wild-type p53 after X-irradiation. These results indicate that the phosphorylation of p53 at Ser15, Thr18, and Ser20 is not necessarily needed for p53 stabilization in response to ionizing radiation

  20. USING QUESTION GENERATING TECHNIQUE IN TEACHING READING COMPREHENSION FOR THE THIRD SEMESTER STUDENTS AT ENGLISH STUDY PROGRAM OF MUHAMMADIYAH UNIVERSITY OF BENGKULU

    Directory of Open Access Journals (Sweden)

    Washlurachim Safitri Safitri

    2016-04-01

    Full Text Available The objective of this research was to find out Using Question Generating Technique Toward Students Reading Comprehension At The Third Semester Students At English Study Program Of Muhammadiyah University Of Bengkulu. The design of this research was Quasi experimental research. The subject of this research is students at the third semester of English study program. They were A class  that consist of 20 students and D class that consist of 20 students. In collecting data, the researcher used some steps; firstly the students were given a pre-test before the researcher applied Question Generating Technique. Then, the researcher did the treatment for three meetings to the experimental class, after that the researcher did post test to both classes. The last, the researcher analyzed the result of reading test by using criteria for the assessment. The final step was the researcher discussed and concluded the data. The result of this research showed that the tobt was  4,880. Whereas, the degree of freedom of post-test is 68, means that the ttable was 2.021. Based on the scores gained, it shows that tobt is higher than ttable (9,911>4,880. There is a significant difference between the post-test mean of the experimental and control class. The result also showed that the students’ comprehension in reading was significantly. In conclusion, the Question Generating Technique had been successfully gave positive effect to the students’ reading comprehension particularly in reading subject in English study program of University Muhammadiyah of Bengkulu.  Key Words : Question Generating Technique, Reading comprehension,

  1. O Talco deve ser utilizado para Pleurodese

    Directory of Open Access Journals (Sweden)

    Steven A. Sahn

    2001-03-01

    Full Text Available RESUMO: A pleurodese està recomendada nos den·ames pleurais malignos quando o tumor não é sensível à quimioterapia. Aprcsenta taxas de sucesso vari:lveis em parte justificadas pelos diferentes agentes e doses utilizadas, a selecção de doentes eo tipo de técnica aplicada. O talco parece ser o agente mais efi caz de pleurodese.Steven Sahn defende que o talco deve ser utilizado para pleurodese, apoiando a sua opini ao em diferentes factores:Mecanisme da pleurodese para talcagcm - o talco após contacto com as células mesoteliais promove um influxo de neutrófil os IL8 mediadus e posterior acumulação de macrófagos, diminuiçãa actividade fibrinolftica e aumento do factor de crescimento dos fi broblastos. Quando o tumor reveste uma grande area de mesotclio, a pleurodese não é tao eficaz.Eficácia - uma revisão da li teratura inglesa de I966 a 1994 constatou que u talco foi o agente mais eficaz de pleurodese, cum uma taxa de sucesso de 93%, comparada cum a da tetraciclina de 67 %, doxicicli na de 72% e bleomicina de 54%. Outras séries reve1aram uma taxa de sucesso do talco sempre superior a 91 %.Custo - o talco é pouco dispendioso e se apl icado em suspensao (“slutTy” por tubo de toracostomia ainda reduz mais os custos inerentes a uma toracoscopia 4uando se utiliza o talco em pó, aprescntando cstas duas tecnicas, taxas ue eticacia scmelhantes. Reacçãoes Adversas Minor e Major Agudas- a toracalgia e a febre são OS efcitos adversos mains frequcntes, frequcntes de todos os agentes de pleurudese. A toracalgia surge em 7% dos doentcs submetiuos a plcurodesc com talco, em 28% com a bleomicina c 40% com a dox iciclina. A tetraciclina provoca geralmente wracalgia grave. A febre surge entre I6 a 69% após talcagem não ultrapassando as 72 horas.As reacçãoes adversas graves sao raras e incluern o cmpiema. arritmia cardfaca e insufcicncia rcspiratória. Se o talco

  2. Batch fabrication of disposable screen printed SERS arrays.

    Science.gov (United States)

    Qu, Lu-Lu; Li, Da-Wei; Xue, Jin-Qun; Zhai, Wen-Lei; Fossey, John S; Long, Yi-Tao

    2012-03-07

    A novel facile method of fabricating disposable and highly reproducible surface-enhanced Raman spectroscopy (SERS) arrays using screen printing was explored. The screen printing ink containing silver nanoparticles was prepared and printed on supporting materials by a screen printing process to fabricate SERS arrays (6 × 10 printed spots) in large batches. The fabrication conditions, SERS performance and application of these arrays were systematically investigated, and a detection limit of 1.6 × 10(-13) M for rhodamine 6G could be achieved. Moreover, the screen printed SERS arrays exhibited high reproducibility and stability, the spot-to-spot SERS signals showed that the intensity variation was less than 10% and SERS performance could be maintained over 12 weeks. Portable high-throughput analysis of biological samples was accomplished using these disposable screen printed SERS arrays.

  3. Mapping and industrial IT project to a 2nd semester design-build project

    DEFF Research Database (Denmark)

    Nyborg, Mads; Høgh, Stig

    2010-01-01

    CDIO means bringing the engineer's daily life and working practice into the educational system. In our opinion this is best done by selecting an appropriate project from industry. In this paper we describe how we have mapped an industrial IT project to a 2nd semester design-build project in the D......CDIO means bringing the engineer's daily life and working practice into the educational system. In our opinion this is best done by selecting an appropriate project from industry. In this paper we describe how we have mapped an industrial IT project to a 2nd semester design-build project...... in the Diploma IT program at the Technical University of Denmark. The system in question is a weighing system operating in a LAN environment. The system is used in the medical industry for producing tablets. We present the design of a curriculum to support the development of major components of the weighing...... system. A simple teaching model for software engineering is presented which combines technical disciplines with disciplines from section 2-4 in the CDIO syllabus. The implementation of a joint project involving several courses supports the CDIO perspective. Already the traditional IT-diploma education...

  4. Assessing critical thinking in medical sciences students in two sequential semesters: Does it improve?

    Science.gov (United States)

    Athari, Zeinab-Sadat; Sharif, Sayyed-Mostafa; Nasr, Ahmad Reza; Nematbakhsh, Mehdi

    2013-01-01

    Critical thinking is an important outcome criterion of higher education in any discipline. Medical and paramedical students always encounter with many new problems in clinical settings and medicinal laboratory, and critical thinking is an essential skill in obtaining a better approach for problem solving. We performed a pre-and post-test to evaluate the change of critical thinking skills in medical sciences students who enrolled in Isfahan University of Medical Sciences in Iran during the academic years 2008-2010. In a longitudinal design study, the critical thinking skills were compared in medical sciences students in two sequential semesters using the California Critical Thinking Skills Test. The test is divided into two parts (parts 1 and 2), including 17 items in each part. Based on proportional stratified sampling, a groups of students (group 1, n=159) were selected from the university population, who enrolled in medicine, pharmacy, nursing, and rehabilitation colleges. The students in group 1 were asked to complete the part 1 of the test (phase I). After one semester, another group (group 2, n=138) from the same population was randomly selected, and they were asked to complete the part two (phase II). The students' demographic data also were recorded. The California critical thinking skills test was translated and it validity and reliability were approved before. No significant difference was observed between the two groups in the demographic data. The students critical thinking scores in phase II significantly reduced in comparison with phase 1 (pstudents' critical thinking.

  5. MODOS DE SER DA JUVENTUDE OCIDENTAL

    Directory of Open Access Journals (Sweden)

    Prof. Dr. Luiz Antônio Dias

    2015-09-01

    Full Text Available O presente artigo é resultado de investigações ainda em andamento no Grupo de Pesquisa “Culturas juvenis, consumo e mobilidade urbana na contemporaneidade”, iniciadas em 2013 junto ao Programa de Mestrado Interdisciplinar em Ciências Humanas da Universidade de Santo Amaro (UNISA. A pesquisa dedica-se a entender, entre outras reflexões, o percurso dos jovens na sociedade contemporânea e as contribuições que eles trouxeram para repensar o espaço urbano. Nesse estudo buscamos localizar no espaço e no tempo em quais condições históricas o sentimento de juventude apareceu para a sociedade. Em seguida, fazemos um minucioso levantamento da trajetória dessa nova categoria social nos mais diferentes períodos da história contemporânea. Chegamos, assim, ao século XX, momento em que as reuniões juvenis deixam de ser fatos isolados e adquirem conotações de manifestações verdadeiramente sociais. Ainda nessa perspectiva de análise, buscamos compreender as similitudes, aproximações e distanciamentos do movimento punk com seus congêneres do passado.

  6. Llegar a ser Simone de Beauvoir

    Directory of Open Access Journals (Sweden)

    Nora Levinton Dolman

    2009-01-01

    Full Text Available A la manera de un Psicoanálisis aplicado a la obra de Simone de Beauvoir se señalan algunos aspectos cruciales que reflejan cómo se va configurando la vida y el pensamiento de una mujer que encarnó, para muchas de nosotras, un modelo de identificación. Su trabajo es en este sentido un espejo y una valiosa muestra de la naturaleza proyectiva de muchos de sus enunciados, donde a partir de su irreemplazable experiencia Simone arriba a conclusiones en las que podemos seguir el rastro de sus vivencias personales. En el contexto singular de su historia personal y en cómo es relatada. Al exponer su vida en sus libros y en numerosas entrevistas concedidas a distintos medios, ha dado lugar a que surgieran diferentes interpretaciones, por lo tanto a que sus palabras y argumentos puedan, como en este artículo, ser utilizados, contrastados entre sí y sometidos a exploración.

  7. Libertas que serás enfermagem

    Directory of Open Access Journals (Sweden)

    Mary Anne Fontenele Martins

    1998-09-01

    Full Text Available O título deste ensaio nos faz lembrar a Inconfidência Mineira, que teve como líder José Joaquim da Silva Xavier, o Tiradentes, sendo um movimento que ansiava por liberdade, assim como a enfermagem que, ao longo dos anos, vem construindo sua história e caminhando em busca de sua autonomia. A presente pesquisa tem como objetivo investigar os caminhos percorridos pela enfermagem, enquanto ciência na busca de sua autonomia, e refletir sobre a atuação do enfermeiro enquanto profissional criativo e autônomo. Estudo respaldado no materialismo histórico e dialético, realizado no período de maio a agosto de 1997 com enfermeiras do Estado do Ceará, que estão envolvidas com o processo histórico da profissão. Os resultados deram origem a uma categoria central, prática profissional e outras três: autonomia, criatividade e disposição para enfrentar desafios, que favoreceram uma melhor compreensão dos caminhos já trilhados pela enfermagem, além de nos permitir entender que o enfermeiro pode ser autônomo e livre.

  8. Depression, stress and anxiety in medical students: A cross-sectional comparison between students from different semesters.

    Science.gov (United States)

    Moutinho, Ivana Lúcia Damásio; Maddalena, Natalia de Castro Pecci; Roland, Ronald Kleinsorge; Lucchetti, Alessandra Lamas Granero; Tibiriçá, Sandra Helena Cerrato; Ezequiel, Oscarina da Silva; Lucchetti, Giancarlo

    2017-01-01

    To compare the prevalence of anxiety, depression, and stress in medical students from all semesters of a Brazilian medical school and assess their respective associated factors. A cross-sectional study of students from the twelve semesters of a Brazilian medical school was carried out. Students filled out a questionnaire including sociodemographics, religiosity (DUREL - Duke Religion Index), and mental health (DASS-21 - Depression, Anxiety, and Stress Scale). The students were compared for mental health variables (Chi-squared/ANOVA). Linear regression models were employed to assess factors associated with DASS-21 scores. 761 (75.4%) students answered the questionnaire; 34.6% reported depressive symptomatology, 37.2% showed anxiety symptoms, and 47.1% stress symptoms. Significant differences were found for: anxiety - ANOVA: [F = 2.536, p=0.004] between first and tenth (p=0.048) and first and eleventh (p=0.025) semesters; depression - ANOVA: [F = 2.410, p=0.006] between first and second semesters (p=0.045); and stress - ANOVA: [F = 2.968, p=0.001] between seventh and twelfth (p=0.044), tenth and twelfth (p=0.011), and eleventh and twelfth (p=0.001) semesters. The following factors were associated with (a) stress: female gender, anxiety, and depression; (b) depression: female gender, intrinsic religiosity, anxiety, and stress; and (c) anxiety: course semester, depression, and stress. Our findings revealed high levels of depression, anxiety, and stress symptoms in medical students, with marked differences among course semesters. Gender and religiosity appeared to influence the mental health of the medical students.

  9. Instaurando maneiras de ser, conhecer e interpretar

    Directory of Open Access Journals (Sweden)

    Maria Stephanou

    1998-01-01

    Full Text Available O artigo propõe a discussão e a problematização do tema "currículo e história". Na primeira parte explicita os fundamentos propostos para a abordagem, as concepções de currículo e história. Na segunda, privilegia as indicações de autores e a experiência pessoal para: a caracterizar o que têm sido os currículos e o ensino de história, particularmente no ensino fundamental, comentan-do suas implicações; b examinar alternativas e encaminhamentos propostos pelos debates da atualidade. Sugere que a aprendizagem de conteúdos históricos na escola, para além da mera aquisição de informações, implica a produção ativa de subjetividades, ou maneiras de ser, conhecer e interpretar o mundo e a si próprio.This article proposes to discuses and to question the theme "curriculum & history". On first part, it explains the fundaments proposed to the dissertation, the conception of curriculum & history. On the second, it grants privilege upon authors remarks and personal experience for purpose to: a characterize what were the curricular activities and the teaching of history, inside primary school particularly, with comments about its implications. b examine alternatives and forwarding proposed by present debates. It suggests that in the school the apprenticeship around historical contents, other than a pure acquisition of information, implies and actives production of subjectivities or manners of being, knowing and interpreting the world and oneself.

  10. Learning styles and types of multiple intelligences in dental students in their first and tenth semester. Monterrey, Mexico, 2015.

    Directory of Open Access Journals (Sweden)

    Juan Solís-Soto

    2016-04-01

    Full Text Available Introduction: Nowadays the incorporation and validation of learning styles and multiple intelligences enable teachers to obtain positive results in academic performance. This new approach has allowed to appreciate personal differences in dental students and strengthen their underdeveloped aspects, improving teaching and learning skills. Objective: To compare learning styles and multiple intelligences in a sample of Mexican dental students in their first and tenth semester. Materials and Methods: A cross-sectional study using questionnaires on learning styles (Honey-Alonso and Gardner’s multiple intelligences was performed. The study was applied to 123 students in their first semester and 157 in their tenth semester at the School of Dentistry at Universidad Autónoma de Nuevo León, evaluating differences between age and sex. Results: Logical-Mathematical intelligence (p=0.044 and Kinesthetic-Corporal intelligence (p=0.042 showed significant differences between students of both semesters, with intrapersonal and interpersonal intelligences being more prevalent. Within learning styles, the prevalent were Reflexive and Theoretical, showing a significant difference between semesters (p=0.005. Conclusion: The most prevalent learning styles in both groups were Reflexive and Theoretical, with no difference between both sexes. The most prevalent types of multiple intelligences in both sexes and groups were interpersonal and intrapersonal.

  11. SERS microscopy: plasmonic nanoparticle probes and biomedical applications

    Science.gov (United States)

    Gellner, M.; Schütz, M.; Salehi, M.; Packeisen, J.; Ströbel, P.; Marx, A.; Schmuck, C.; Schlücker, S.

    2010-08-01

    Nanoparticle probes for use in targeted detection schemes and readout by surface-enhanced Raman scattering (SERS) comprise a metal core, Raman reporter molecules and a protective shell. One design of SERS labels specifically optimized for biomedical applications in conjunction with red laser excitation is based on tunable gold/silver nanoshells, which are completely covered by a self-assembled monolayer (SAM) of Raman reporters. A shell around the SAM-coated metal core stabilizes the colloid and prevents particle aggregation. The optical properties and SERS efficiencies of these plasmonic nanostructures are characterized both experimentally and theoretically. Subsequent bioconjugation of SERS probes to ligands such as antibodies is a prerequisite for the selective detection of the corresponding target molecule via the characteristic Raman signature of the label. Biomedical imaging applications of SERS-labeled antibodies for tumor diagnostics by SERS microscopy are presented, using the localization of the tumor suppressor p63 in prostate tissue sections as an example.

  12. SERS study of transformation of phenylalanine to tyrosine under particle irradiation

    Science.gov (United States)

    Zhang, Jingjing; Huang, Qing; Yao, Guohua; Ke, Zhigang; Zhang, Hong; Lu, Yilin

    2014-08-01

    Surface enhanced Raman scattering or spectroscopy (SERS) is a very powerful analytical tool which has been widely applied in many scientific research and application fields. It is therefore also very intriguing for us to introduce SERS technique in the radiobiological research, where in many cases only a very few of biomolecules are subjected to changes which however can lead to significant biological effects. The radiation induced biochemical reactions are normally very sophisticated with different substances produced in the system, so currently it is still a big challenge for SERS to analyze such a mixture system which contains multiple analytes. In this context, this work aimed to establish and consolidate the feasibility of SERS as an effective tool in radiation chemistry, and this purpose, we employed SERS as a sensitive probe to a known process, namely, the oxidation of phenylalanine (Phe) under particle irradiation, where the energetic particles were obtained from either plasma discharge or electron-beam. During the irradiation, three types of tyrosine (Tyr), namely, p-Tyr, m-Tyr and o-Tyr were produced, and all these tyrosine isomers together with Phe could be identified and measured based on the SERS spectral analysis of the corresponding enhanced characteristic signals, namely, 1002 cm-1 for Phe, 1161 cm-1 for p-Tyr, 990 cm-1 for m-Tyr, and 970 cm-1 for o-Tyr, respectively. The estimation of the quantities of different tyrosine isomers were also given and verified by conventional method such as high performance liquid chromatography (HPLC). As for comparison of different ways of particle irradiation, our results also indicated that electron-beam irradiation was more efficient for converting Phe into Tyr than plasma discharge treatment, confirming the role of hydroxyl radicals in the Phe-Tyr conformation. Therefore, our work has not only demonstrated that SERS can be successfully applied in the radiobiological study, but also given insights into the

  13. Label-free in situ SERS imaging of biofilms.

    Science.gov (United States)

    Ivleva, Natalia P; Wagner, Michael; Szkola, Agathe; Horn, Harald; Niessner, Reinhard; Haisch, Christoph

    2010-08-12

    Surface-enhanced Raman scattering (SERS) is a promising technique for the chemical characterization of biological systems. It yields highly informative spectra, can be applied directly in aqueous environment, and has high sensitivity in comparison with normal Raman spectroscopy. Moreover, SERS imaging can provide chemical information with spatial resolution in the micrometer range (chemical imaging). In this paper, we report for the first time on the application of SERS for in situ, label-free imaging of biofilms and demonstrate the suitability of this technique for the characterization of the complex biomatrix. Biofilms, being communities of microorganisms embedded in a matrix of extracellular polymeric substances (EPS), represent the predominant mode of microbial life. Knowledge of the chemical composition and the structure of the biofilm matrix is important in different fields, e.g., medicine, biology, and industrial processes. We used colloidal silver nanoparticles for the in situ SERS analysis. Good SERS measurement reproducibility, along with a significant enhancement of Raman signals by SERS (>10(4)) and highly informative SERS signature, enables rapid SERS imaging (1 s for a single spectrum) of the biofilm matrix. Altogether, this work illustrates the potential of SERS for biofilm analysis, including the detection of different constituents and the determination of their distribution in a biofilm even at low biomass concentration.

  14. The development and nature of problem-solving among first-semester calculus students

    Science.gov (United States)

    Dawkins, Paul Christian; Mendoza Epperson, James A.

    2014-08-01

    This study investigates interactions between calculus learning and problem-solving in the context of two first-semester undergraduate calculus courses in the USA. We assessed students' problem-solving abilities in a common US calculus course design that included traditional lecture and assessment with problem-solving-oriented labs. We investigate this blended instruction as a local representative of the US calculus reform movements that helped foster it. These reform movements tended to emphasize problem-solving as well as multiple mathematical registers and quantitative modelling. Our statistical analysis reveals the influence of the blended traditional/reform calculus instruction on students' ability to solve calculus-related, non-routine problems through repeated measures over the semester. The calculus instruction in this study significantly improved students' performance on non-routine problems, though performance improved more regarding strategies and accuracy than it did for drawing conclusions and providing justifications. We identified problem-solving behaviours that characterized top performance or attrition in the course. Top-performing students displayed greater algebraic proficiency, calculus skills, and more general heuristics than their peers, but overused algebraic techniques even when they proved cumbersome or inappropriate. Students who subsequently withdrew from calculus often lacked algebraic fluency and understanding of the graphical register. The majority of participants, when given a choice, relied upon less sophisticated trial-and-error approaches in the numerical register and rarely used the graphical register, contrary to the goals of US calculus reform. We provide explanations for these patterns in students' problem-solving performance in view of both their preparation for university calculus and the courses' assessment structure, which preferentially rewarded algebraic reasoning. While instruction improved students' problem

  15. The Correlation Between Parenting Parents' and Students' Motivation in Learning English on 4rd Semester at the Faculty of Teacher Training and Education (Fkip) University Batanghari Jambi Academic Year 2016/2017

    OpenAIRE

    dewi, kartika

    2017-01-01

    Parenting parents is very important for children to provide encouragement or motivation in learning. With parenting a good influence for children, although many types of parenting applied parents' of children dependent parents' upbringing is applied parents to children.. The purpose in this research want to know whether there is any correlation between Parenting Parents' and Students Motivation in learning English on43rd Semester at the Faculty of Teacher Training and Education (FKIP) Univers...

  16. Development of depression and deterioration in quality of life in German dental medical students in preclinical semesters.

    Science.gov (United States)

    Burger, P H M; Neumann, C; Ropohl, A; Paulsen, F; Scholz, M

    2016-11-01

    Early intervention to counter mental disorders during the course of studies in dentistry is indicated in view of the pronounced prevalence of burnout in this student collective. To assess the proportion of students in whom these risk states can be quantified in measurable parameters for concrete mental disorders, we conducted surveys among students of dental medicine during the first 2.5 years of their studies. We surveyed a total of 163 students of dental medicine in their first 5 semesters of study. Standardized, validated psychological questionnaires on depressive symptoms (Beck Depression Inventory; BDI-II) and mental and physical quality of life (Short Form Survey; SF-12) were used in the survey, with per-semester participant quotas of around 90%. Regarding depression, the students were within the range of the normal populace at the beginning of the 1st semester. Symptoms of depression then became more pronounced with every succeeding semester. In the fifth semester, the average levels determined were equivalent to a depression with a clinical treatment indication. Hardly any change was registered for physical wellbeing in the quality of life questionnaire. The mental sum scores, however, reflected dramatic downturns in quality of life. Highly significant correlations between the parameters described here - depressivity and mental quality of life - were observed in all semesters. The participating students begin their course of studies at the level of the average populace for the symptoms surveyed, then develop, on average, a clinically manifest depression after 2.5 years. The personal experience of a deterioration of mental quality of life appears to be crucial in the phenomena observed. Copyright © 2016 Elsevier GmbH. All rights reserved.

  17. Myofilament Calcium Sensitivity: Mechanistic Insight into TnI Ser-23/24 and Ser-150 Phosphorylation Integration

    Directory of Open Access Journals (Sweden)

    Hussam E Salhi

    2016-12-01

    Full Text Available Troponin I (TnI is a major regulator of cardiac muscle contraction and relaxation. During physiological and pathological stress, TnI is differentially phosphorylated at multiple residues through different signaling pathways to match cardiac function to demand. The combination of these TnI phosphorylations can exhibit an expected or unexpected functional integration, whereby the function of two phosphorylations are different than that predicted from the combined function of each individual phosphorylation alone. We have shown that TnI Ser-23/24 and Ser-150 phosphorylation exhibit functional integration and are simultaneously increased in response to cardiac stress. In the current study, we investigated the functional integration of TnI Ser-23/24 and Ser-150 to alter cardiac contraction. We hypothesized that Ser-23/24 and Ser-150 phosphorylation each utilize distinct molecular mechanisms to alter the TnI binding affinity within the thin filament. Mathematical modeling predicts that Ser-23/24 and Ser-150 phosphorylation affect different TnI affinities within the thin filament to distinctly alter the Ca2+-binding properties of troponin. Protein binding experiments validate this assertion by demonstrating pseudo-phosphorylated Ser-150 decreases the affinity of isolated TnI for actin, whereas Ser-23/24 pseudo-phosphorylation is not different from unphosphorylated. Thus, our data supports that TnI Ser-23/24 affects TnI-TnC binding, while Ser-150 phosphorylation alters TnI-actin binding. By measuring force development in troponin-exchanged skinned myocytes, we demonstrate that the Ca2+ sensitivity of force is directly related to the amount of phosphate present on TnI. Furthermore, we demonstrate that Ser-150 pseudo-phosphorylation blunts Ser-23/24-mediated decreased Ca2+-sensitive force development whether on the same or different TnI molecule. Therefore, TnI phosphorylations can integrate across troponins along the myofilament. These data demonstrate

  18. QUE É O "SER DA FAMÍLIA"?

    Directory of Open Access Journals (Sweden)

    Josefa Aida Delgado

    2005-01-01

    Full Text Available Es un estudio basado en la filosofía fenomenológica heideggeriana, su propósito es desvelar los elementos estructurales de la existencia del "ser de la familia". El camino metodológico fue construido con base en el pensamiento de Heidegger. Los datos de la familia fueron recolectados por medio de las entrevistas y las observaciones. Cada uno de nosotros contribuye para su existencia, y ella posibilita el desarrollo de nuestro "ser-en el-mundo" al vivenciar y compartir experiencias cotidianas de la familia. Allí surge la posibilidad de compartir un modo de ser en el mundo, un modo de cuidado para "ser familia en el mundo". Un mundo que genera esa unidad de relacionamiento que emerge de sentimientos interligados entre los integrantes, respondiendo a las exigencias de cada miembro, por el sentimiento de pertenencia primaria generado en ellos. Esa unidad da la posibilidad de nacer a cada uno de nosotros, asi también, nos da la posibilidad de poder ser ser humano, llegando a ser un referencial de sí misma en cada ser humano.

  19. IR, Raman and SERS studies of methyl salicylate

    Science.gov (United States)

    Varghese, Hema Tresa; Yohannan Panicker, C.; Philip, Daizy; Mannekutla, James R.; Inamdar, S. R.

    2007-04-01

    The IR and Raman spectra of methyl salicylate (MS) were recorded and analysed. Surface enhanced Raman scattering (SERS) spectrum was recorded in silver colloid. The vibrational wave numbers of the compound have been computed using the Hartree-Fock/6-31G * basis and compared with the experimental values. SERS studies suggest a flat orientation of the molecule at the metal surface.

  20. Pengaruh Metode Demonstrasi Terhadap Prestasi Belajar Mata Pelajaran Pemeliharaan/servisSistem Pengapian Konvensional Siswa Kelas XI Semester Genap SMK Tamansiswa Yogyakarta TahunAjaran 2013/2014

    Directory of Open Access Journals (Sweden)

    Bahtiar Wilantara

    2014-12-01

    Full Text Available This study aims to determine the method of demonstration effect is better than the lecture method of learning achievement maintenance / servicing of conventional ignition systems of SMK Tamansiswa Yogyakarta. This research was conducted at SMK Tamansiswa Yogyakarta in May and June 2014. This type of research is quasi-experimental. The population in this study are 61 students of class XI. The sampling technique using saturation sampling technique. Class XI was chosen from class A and class XI B controls selected as the experimental class. Data collection techniques learning achievement maintenance / servicing of conventional ignition system use a pretest and posttest. Test the validity of the instrument using the judgment experts. Before the items were used for the study, it has been previously tested in class XI C in April 2014. The reliability problem is obtained using the formula K - 20, the results of R11 = 0.933, p = 0.000, so the matter declared reliable. Data analysis techniques were calculated using t-test, prior to the trial to test the prerequisite analysis includes tests of normality and homogeneity tests. Descriptive research results show that the trend of learning achievement maintenance / servicing of conventional ignition systems of class XI student of SMK Tamansiswa Yogyakarta semester academic year 2013/2014 is taught using lecture method included in the medium category and the method of demonstration in the very high category. In the t-test obtained t = 20.200 and p = 0.000, for p < 0.005 means that there are significant differences of learning achievement maintenance / servicing of conventional ignition systems of class XI student of SMK Tamansiswa Yogyakarta semester 2013/2014 academic year. They are taught using the lecture method and demonstration method. Judging from the average hasi turns teaching methods using the method demonstration of 24.345 and 13.897 of the lecture method, this means the method of demonstration

  1. Photonic Crystal Fibre SERS Sensors Based on Silver Nanoparticle Colloid

    International Nuclear Information System (INIS)

    Zhi-Guo, Xie; Yong-Hua, Lu; Pei, Wang; Kai-Qun, Lin; Jie, Yan; Hai, Ming

    2008-01-01

    A photonic crystal fibre (PCF) surface enhanced Raman scattering (SERS) sensor is developed based on silver nanoparticle colloid. Analyte solution and silver nanoparticles are injected into the air holes of PCF by a simple modified syringe to overcome mass-transport constraints, allowing more silver nanoparticles involved in SERS activity. This sensor offers significant benefit over the conventional SERS sensor with high flexibility, easy manufacture. We demonstrate the detection of 4-mercaptobenzoic acid (4-MBA) molecules with the injecting way and the common dipping measurement. The injecting way shows obviously better results than the dipping one. Theoretical analysis indicates that this PCF SERS substrate offers enhancement of about 7 orders of magnitude in SERS active area

  2. GAMBARAN KEBIASAAN MENGONSUMSI MAKANAN CEPAT SAJI DAN OBESITAS PADA MAHASISWA SEMESTER V PROGRAM STUDI KEDOKTERAN UMUM UNIVERSITAS UDAYANA TAHUN 2014

    Directory of Open Access Journals (Sweden)

    Ratih Pradnyandari Pemayun

    2015-09-01

    Full Text Available OVERVIEW OF CONSUMING FAST FOOD HABIT AND OBESITY IN MEDICAL STUDENTS AT UDAYANA UNIVERSITY 2014 ABSTRACT Background : Obesity has been occured by deposit of fat in subcutaneous and intra abdominal tissue. The prevalance of obesity in Indonesian womens were 32,9% and mens is 19,7 % respectively. In general side, the prevalence of obesity in 18 years old adult peoples were 15,4%. The major risk factors for obesity including lifestyle dietary changes such as consuming fast food habit. Objective : to find out overview of consuming fast food habit and obesity in medical students. Method : This research was cross-sectional decriptive study. The respondens were 127 medical students on 5th semester in Udayana University on 2014. The qualitative data were be measured by questionnaires. The variables were including age, gender, general knowledge of parents, parental income monthy, body mass index (BMI, habit of consuming fast food, average outcome monlty of medical students, and daily frequency of consuming fast food. Result : the characteristic respondens including : a mostly 20 years old, b.women more than men, c. level education of parents were university, d. monthly parental income more than 5 million rupiah, e. BMI in normal limit, f.degree of obesity were grade I, g.inconvience consuming fast food daily, h.monthy outcome of medical students were aproximately 500.000 rupiah, and i.regular consuming fast food mostly once weekly. Conclusion : mostly responden were women with normaly of BMI and inconvenience consuming fast food daily. Key word : obesity, consuming fast food, medical students, outcome montly

  3. The Changing Motivations of Students' Use of Lecture Podcasts across a Semester: An Extended Theory of Planned Behaviour Approach

    Science.gov (United States)

    Moss, Nathan D.; Hamilton, Kyra; White, Katherine M.; Hansen, Julie

    2015-01-01

    We extended the previous work of Moss, O'Connor and White, to include a measure of group norms within the theory of planned behaviour (TPB), to examine the influences on students' decisions to use lecture podcasts as part of their learning. Participants (N?=?90) completed the extended TPB predictors before semester began (Time 1) and mid-semester…

  4. Losing Sleep over It: Daily Variation in Sleep Quantity and Quality in Canadian Students' First Semester of University

    Science.gov (United States)

    Galambos, Nancy L.; Dalton, Andrea L.; Maggs, Jennifer L.

    2009-01-01

    Daily covariation of sleep quantity and quality with affective, stressful, academic, and social experiences were observed in a sample of Canadian 17-19-year-olds in their first year of university. Participants (N = 191) completed web-based checklists for 14 consecutive days during their first semester. Multilevel models predicting sleep quantity…

  5. From Idea to Action: Promoting Responsible Management Education through a Semester-Long Academic Integrity Learning Project

    Science.gov (United States)

    Lavine, Marc H.; Roussin, Christopher J.

    2012-01-01

    The authors describe a semester-long action-learning project where undergraduate or graduate management students learn about ethics, responsibility, and organizational behavior by examining the policy of their college or university that addresses academic integrity. Working in teams, students adopt a stakeholder management approach as they make…

  6. Performance of First-Year Health Sciences Students in a Large, Diverse, Multidisciplinary, First-Semester, Physiology Service Module

    Science.gov (United States)

    Tufts, Mark; Higgins-Opitz, Susan B.

    2014-01-01

    Health Science students at the University of KwaZulu-Natal perform better in their professional modules compared with their physiology modules. The pass rates of physiology service modules have steadily declined over the years. While a system is in place to identify "at-risk" students, it is only activated after the first semester. As a…

  7. Enhancing Student Performance in First-Semester General Chemistry Using Active Feedback through the World Wide Web

    Science.gov (United States)

    Chambers, Kent A.; Blake, Bob

    2007-01-01

    The World Wide Web recently launched a new interactive feedback system for the instructors, so that can better understanding about their students and their problems. The feedback, in combination with tailored lectures is expected to enhance student performance in the first semester of general chemistry.

  8. Medialogi (Dansk informations brochure om Medialogi-uddannelsen, 1. til 10. semester (B.Sc. & Cand.Scient))

    DEFF Research Database (Denmark)

    Nordahl, Rolf; Andersen, Hans Jørgen

    2006-01-01

    Informationsbrochure, 28 sider, om Medialogi uddannelsen (Cand. Scient.), der udbydes af Aalborg Universitet i Aalborg, Esbjerg og København. Brochuren beskriver 1. til 10. semester af uddannelsen (B.Sc. og M.Sc.). Informationen er primært rettet mod potentielle ansøgere til Medialogi uddannelsen...

  9. The Indirect Effect of Alcohol Use on GPA in First-Semester College Students: The Mediating Role of Academic Effort

    Science.gov (United States)

    Conway, James M.; DiPlacido, Joanne

    2015-01-01

    This study focused on first-semester college students, investigating (a) indirect effects of aggregate alcohol use on grade point average (GPA) through academic effort (skipping class and time on schoolwork) and (b) daily effects of alcohol use on reduced effort. Eighty students reported daily alcohol use and academic effort (skipping class and…

  10. SERS Nanosensors for in vivo Glucose Sensing

    Science.gov (United States)

    2017-09-01

    R. Singh, A. Z. Alkilani, M. T. C. McCrudden, S. O’Neill, C. O’Mahony, K. Armstrong, N. McLoone, P. Kole and A. D. Woolfson, Int J Pharmaceut , 2013...10-14 year-old girl and boy scouts from the Chicago area) to communicate about nanotechnology research and careers in science . Plan for the next...Nothing to Report. Impact on technology transfer Nothing to report Impact on society beyond science and technology Nothing to report

  11. Development of optimized nanogap plasmonic substrate for improved SERS enhancement

    Directory of Open Access Journals (Sweden)

    Jayakumar Perumal

    2017-05-01

    Full Text Available SERS enhancement factor (EF of planar substrates depends on the size and shape of the fine nanostructure forming a defect free, well-arranged matrix. Nano-lithographic process is considered to be the most advanced methods employed for the fabrication SERS substrates. Nanostructured plasmonic substrates with nanogap (NG pattern often results in stable, efficient and reproducible SERS enhancement. For such substrates, NG and their diagonal length (DL need to be optimized. Theoretically smaller NGs (∼30-40 nm or smaller results in higher SERS enhancement. However, fabrication of NG substrates below such limit is a challenge even for the most advanced lithography process. In this context, herein, we report the optimization of fabrication process, where higher SERS enhancement can be realized from larger NGs substrates by optimizing their DL of nanostructures between the NGs. Based on simulation we could demonstrate that, by optimizing the DL, SERS enhancement from larger NG substrate such as 60 and 80 nm could be comparable to that of smaller (40nm NG substrates. We envision that this concept will open up new regime in the nanofabrication of practically feasible NG based plasmonic substrates with higher SERS enhancement. Initial results of our experiments are in close agreement with our simulated study.

  12. One semester course in wind energy for advanced undergraduate and graduate engineering students

    International Nuclear Information System (INIS)

    Ghosh, K.

    2006-01-01

    The recent increase in energy consumption in India is resulting in high levels of greenhouse gas emissions. Attempts to harness new renewable energy sources such as wind power is creating the need for trained manpower in aerospace engineering and mechanical engineering. The course outline for a one semester course in wind energy for advanced undergraduate and graduate engineering students at the Indian Institute of Technology was presented in this paper. A history of wind energy was also presented along with the approaching global environmental crisis. International efforts and conventions to reduce greenhouse gas emissions were discussed. India's geography and relationship to wind resources were presented in terms of its latitude and geostrophic winds. The course outline also includes a section on measuring instruments (anemometers) and organization of wind data using Weibull distribution as well as the impacts of summer and monsoon winds. The aerodynamics of wind turbines including airfoils, airscrew theory, and its application to wind turbines were discussed. Rural and remote area usage of wind turbines as well as the structural design and construction of wind turbine blades using composite materials are also examined in the course. Last, the course presents a video cassette and a 16 mm film on wind energy and advises students that they are exposed to laboratory and field practices and encouraged to do practical projects. The course contains a discussion of policy issues such as reaching the common people, and industry-academia interaction. 8 refs., 10 figs

  13. Fostering internationalization: an American-Danish semester-long undergraduate nursing student exchange program.

    Science.gov (United States)

    Baernholdt, M; Drake, E; Maron, F; Neymark, K

    2013-06-01

    This paper describes the development, implementation and evaluation of a semester-long exchange program between two Bachelor of Science in Nursing programs in the USA and Denmark. Nurses globally need to provide culturally sensitive care for an ethnically diverse population. Competencies on how to do so should start in basic nursing programs. A useful strategy is through immersion into another culture through an exchange program. Little is known about successful strategies for two-way or 360° exchange programs between schools from different countries. Guided by experiential learning theory, we developed an exchange program with the objective of enhancing nursing students' cultural competence through knowledge building, attitudes and behaviour development. Lessons learned and implications for educational institutions and policy are discussed. In internationalization of nursing education, an awareness of underlying cultural values regarding nursing competence and taking appropriate action are important for success. Other areas for a successful exchange program include matching of courses or content across schools, clear objectives and evaluation plans. Finally, flexibility and open communication are key components when setting up a 360° exchange program. © 2013 The Authors. International Nursing Review © 2013 International Council of Nurses.

  14. Interpersonal goals and change in anxiety and dysphoria in first-semester college students.

    Science.gov (United States)

    Crocker, Jennifer; Canevello, Amy; Breines, Juliana G; Flynn, Heather

    2010-06-01

    Two longitudinal studies examined the associations between interpersonal goals (i.e., self-image and compassionate goals) and anxiety and dysphoria (i.e., distress). In Study 1, 199 college freshmen (122 women, 77 men) completed 12 surveys over 12 weeks. Compassionate goals predicted decreased distress, and self-image goals predicted increased distress from pretest to posttest when distress was assessed as anxiety, dysphoria, or a composite, and when the goals were worded as approach goals, avoidance goals, or a composite. In Study 2, 115 first-semester roommate pairs (86 female and 29 male pairs) completed 12 surveys over 12 weeks. Compassionate and self-image goals predicted distress in same-week, lagged-week, and pretest-to-posttest analyses; effects of compassionate goals remained significant when the authors controlled for several known risk factors. Having clear goals consistently explained the association between compassionate goals but not self-image goals and distress. Results supported a path model in which compassionate goals predict increased support given to roommates, which predicts decreased distress. Results also supported a reciprocal association; chronic distress predicted decreased compassionate and increased self-image goals from pretest to posttest, and weekly distress predicted decreased compassionate goals the subsequent week. The results suggest that compassionate goals contribute to decreased distress because they provide meaning and increase support given to others. Distress, in turn, predicts change in goals, creating the potential for upward and downward spirals of goals and distress. (c) 2010 APA, all rights reserved).

  15. The understanding of core pharmacological concepts among health care students in their final semester.

    Science.gov (United States)

    Aronsson, Patrik; Booth, Shirley; Hägg, Staffan; Kjellgren, Karin; Zetterqvist, Ann; Tobin, Gunnar; Reis, Margareta

    2015-12-29

    The overall aim of the study was to explore health care students´ understanding of core concepts in pharmacology. An interview study was conducted among twelve students in their final semester of the medical program (n = 4), the nursing program (n = 4), and the specialist nursing program in primary health care (n = 4) from two Swedish universities. The participants were individually presented with two pharmacological clinically relevant written patient cases, which they were to analyze and propose a solution to. Participants were allowed to use the Swedish national drug formulary. Immediately thereafter the students were interviewed about their assessments. The interviews were audio-recorded and transcribed verbatim. A thematic analysis was used to identify units of meaning in each interview. The units were organized into three clusters: pharmacodynamics, pharmacokinetics, and drug interactions. Subsequent procedure consisted of scoring the quality of students´ understanding of core concepts. Non-parametric statistics were employed. The study participants were in general able to define pharmacological concepts, but showed less ability to discuss the meaning of the concepts in depth and to implement these in a clinical context. The participants found it easier to grasp concepts related to pharmacodynamics than pharmacokinetics and drug interactions. These results indicate that education aiming to prepare future health care professionals for understanding of more complex pharmacological reasoning and decision-making needs to be more focused and effective.

  16. Pengaruh Latihan Tari Legong Terhadap Kebugaran Fisik Mahasiswi Semester VI dan VIII Fakultas Kedokteran Universitas Udayana

    Directory of Open Access Journals (Sweden)

    K. G. Budhi Riyanta

    2013-04-01

    Full Text Available Sport is a way to promote health and prevent degenerative diseases. Sport has great benefits in improving physical fitness and maintaining ideal body weight. This study found that the potentials of domestic culture can be used as a form of sports. Legong dance is one of popular Balinese tradisional art which has dynamic movements with duration of 20 minutes. A randomized pre-test and post-test contol group design was carried out to compare the effectiveness of the Balinese Legong dance with Senam Ayo Bersatu (one of aerobic dance in improving physical fitness and reducing body fat. Thirty samples who came from the sixth and eighth semester in the Faculty of Medicine Udayana University were divided into three different groups: I (Legong dance intervention, II (Senam Ayo Bersatu intervention, and control (without intervention. The intervention was done in 40 minutes for 8 weeks with three times intervention/week. Time of 2.4 km run as parameter of physical fitnees and body fat percentage was measured before starting the intervention and at last eighth weeks. It was elicited the significant difference (p?0.05 that Legong dance was more effective as Senam Ayo Bersatu in improving physical fitness and maintain body fat composition.

  17. One semester course in wind energy for advanced undergraduate and graduate engineering students

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, K. [Indian Inst. of Technology, Kanpur (India). Aerospace Engineering Dept.

    2006-07-01

    The recent increase in energy consumption in India is resulting in high levels of greenhouse gas emissions. Attempts to harness new renewable energy sources such as wind power is creating the need for trained manpower in aerospace engineering and mechanical engineering. The course outline for a one semester course in wind energy for advanced undergraduate and graduate engineering students at the Indian Institute of Technology was presented in this paper. A history of wind energy was also presented along with the approaching global environmental crisis. International efforts and conventions to reduce greenhouse gas emissions were discussed. India's geography and relationship to wind resources were presented in terms of its latitude and geostrophic winds. The course outline also includes a section on measuring instruments (anemometers) and organization of wind data using Weibull distribution as well as the impacts of summer and monsoon winds. The aerodynamics of wind turbines including airfoils, airscrew theory, and its application to wind turbines were discussed. Rural and remote area usage of wind turbines as well as the structural design and construction of wind turbine blades using composite materials are also examined in the course. Last, the course presents a video cassette and a 16 mm film on wind energy and advises students that they are exposed to laboratory and field practices and encouraged to do practical projects. The course contains a discussion of policy issues such as reaching the common people, and industry-academia interaction. 8 refs., 10 figs.

  18. Frequency and Content of Chat Questions by Time of Semester at the University of Central Florida: Implications for Training, Staffing and Marketing

    Science.gov (United States)

    Goda, Donna; Bishop, Corinne

    2008-01-01

    The more than 4,000 "chats" received by the University of Central Florida's (UCF) Ask-A-Librarian digital reference service are the subject of this practitioner-based, descriptive case study. Question content from chats received during four semesters between January 2005 and May 2006 are categorized and plotted, by semester, to show the…

  19. Historia de una coma. Gadamer y el sentido del ser

    OpenAIRE

    Vattimo, Gianni

    2005-01-01

    A partir de la doble posibilidad de traducir en las lenguas románicas la expresión gadameriana «Sein, das verstanden werden kann, ist Sprache» como «El ser, que puede ser comprendido, es lenguaje» o como «El ser que puede ser comprendido es lenguaje», se consideran las importantes repercusiones ontológicas que tendría una interpretación más moderada (y más habitual) de ese enunciado (la primera exhibida), o una lectura más radical y nihilista (la que aquí se defiende) del mismo (la ...

  20. Dynamic SERS nanosensor for neurotransmitter sensing near neurons.

    Science.gov (United States)

    Lussier, Félix; Brulé, Thibault; Bourque, Marie-Josée; Ducrot, Charles; Trudeau, Louis-Éric; Masson, Jean-François

    2017-12-04

    Current electrophysiology and electrochemistry techniques have provided unprecedented understanding of neuronal activity. However, these techniques are suited to a small, albeit important, panel of neurotransmitters such as glutamate, GABA and dopamine, and these constitute only a subset of the broader range of neurotransmitters involved in brain chemistry. Surface-enhanced Raman scattering (SERS) provides a unique opportunity to detect a broader range of neurotransmitters in close proximity to neurons. Dynamic SERS (D-SERS) nanosensors based on patch-clamp-like nanopipettes decorated with gold nanoraspberries can be located accurately under a microscope using techniques analogous to those used in current electrophysiology or electrochemistry experiments. In this manuscript, we demonstrate that D-SERS can measure in a single experiment ATP, glutamate (glu), acetylcholine (ACh), GABA and dopamine (DA), among other neurotransmitters, with the potential for detecting a greater number of neurotransmitters. The SERS spectra of these neurotransmitters were identified with a barcoding data processing method and time series of the neurotransmitter levels were constructed. The D-SERS nanosensor was then located near cultured mouse dopaminergic neurons. The detection of neurotransmitters was performed in response to a series of K + depolarisations, and allowed the detection of elevated levels of both ATP and dopamine. Control experiments were also performed near glial cells, showing only very low basal detection neurotransmitter events. This paper demonstrates the potential of D-SERS to detect neurotransmitter secretion events near living neurons, but also constitutes a strong proof-of-concept for the broad application of SERS to the detection of secretion events by neurons or other cell types in order to study normal or pathological cell functions.

  1. Surface enhanced Raman scattering (SERS) fabrics for trace analysis

    International Nuclear Information System (INIS)

    Liu, Jun; Zhou, Ji; Tang, Bin; Zeng, Tian; Li, Yaling; Li, Jingliang; Ye, Yong; Wang, Xungai

    2016-01-01

    Highlights: • Gold nanoparticles are in-situ synthesized on silk fabrics by heating. • Flexible silk fabrics with gold nanoparticles are used for surface-enhanced Raman scattering (SERS). • SERS activities of silk fabrics with different gold contents are investigated. - Abstract: Flexible SERS active substrates were prepared by modification of silk fabrics with gold nanoparticles. Gold nanoparticles were in-situ synthesized after heating the silk fabrics immersed in gold ion solution. Localized surface plasmon resonance (LSPR) properties of the treated silk fabrics varied as the concentration of gold ions changed, in relation to the morphologies of gold nanoparticles on silk. In addition, X-ray diffraction (XRD) was used to observe the structure of the gold nanoparticle treated silk fabrics. The SERS enhancement effect of the silk fabrics treated with gold nanoparticles was evaluated by collecting Raman signals of different concentrations of p-aminothiophenol (PATP), 4-mercaptopyridine (4-MPy) and crystal violet (CV) solutions. The results demonstrate that the silk fabrics corresponding to 0.3 and 0.4 mM of gold ions possess high SERS activity compared to the other treated fabrics. It is suggested that both the gold content and morphologies of gold nanoparticles dominate the SERS effect of the treated silk fabrics.

  2. Superhydrophobic Ag nanostructures on polyaniline membranes with strong SERS enhancement.

    Science.gov (United States)

    Liu, Weiyu; Miao, Peng; Xiong, Lu; Du, Yunchen; Han, Xijiang; Xu, Ping

    2014-11-07

    We demonstrate here a facile fabrication of n-dodecyl mercaptan-modified superhydrophobic Ag nanostructures on polyaniline membranes for molecular detection based on SERS technique, which combines the superhydrophobic condensation effect and the high enhancement factor. It is calculated that the as-fabricated superhydrophobic substrate can exhibit a 21-fold stronger molecular condensation, and thus further amplifies the SERS signal to achieve more sensitive detection. The detection limit of the target molecule, methylene blue (MB), on this superhydrophobic substrate can be 1 order of magnitude higher than that on the hydrophilic substrate. With high reproducibility, the feasibility of using this SERS-active superhydrophobic substrate for quantitative molecular detection is explored. A partial least squares (PLS) model was established for the quantification of MB by SERS, with correlation coefficient R(2) = 95.1% and root-mean-squared error of prediction (RMSEP) = 0.226. We believe this superhydrophobic SERS substrate can be widely used in trace analysis due to its facile fabrication, high signal reproducibility and promising SERS performance.

  3. Surface enhanced Raman scattering (SERS) fabrics for trace analysis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jun [National Engineering Laboratory for Advanced Yarn and Fabric Formation and Clean Production, Wuhan Textile University, Wuhan 430073 (China); Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials & Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education & College of Chemistry & Chemical Engineering, Hubei University, Wuhan 430062 (China); Zhou, Ji [Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials & Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education & College of Chemistry & Chemical Engineering, Hubei University, Wuhan 430062 (China); Tang, Bin, E-mail: bin.tang@deakin.edu.au [National Engineering Laboratory for Advanced Yarn and Fabric Formation and Clean Production, Wuhan Textile University, Wuhan 430073 (China); Institute for Frontier Materials, Deakin University, Geelong, Victoria 3216 (Australia); Zeng, Tian; Li, Yaling [Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials & Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education & College of Chemistry & Chemical Engineering, Hubei University, Wuhan 430062 (China); Li, Jingliang [Institute for Frontier Materials, Deakin University, Geelong, Victoria 3216 (Australia); Ye, Yong, E-mail: yeyong@hubu.edu.cn [Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials & Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education & College of Chemistry & Chemical Engineering, Hubei University, Wuhan 430062 (China); Wang, Xungai [National Engineering Laboratory for Advanced Yarn and Fabric Formation and Clean Production, Wuhan Textile University, Wuhan 430073 (China); Institute for Frontier Materials, Deakin University, Geelong, Victoria 3216 (Australia)

    2016-11-15

    Highlights: • Gold nanoparticles are in-situ synthesized on silk fabrics by heating. • Flexible silk fabrics with gold nanoparticles are used for surface-enhanced Raman scattering (SERS). • SERS activities of silk fabrics with different gold contents are investigated. - Abstract: Flexible SERS active substrates were prepared by modification of silk fabrics with gold nanoparticles. Gold nanoparticles were in-situ synthesized after heating the silk fabrics immersed in gold ion solution. Localized surface plasmon resonance (LSPR) properties of the treated silk fabrics varied as the concentration of gold ions changed, in relation to the morphologies of gold nanoparticles on silk. In addition, X-ray diffraction (XRD) was used to observe the structure of the gold nanoparticle treated silk fabrics. The SERS enhancement effect of the silk fabrics treated with gold nanoparticles was evaluated by collecting Raman signals of different concentrations of p-aminothiophenol (PATP), 4-mercaptopyridine (4-MPy) and crystal violet (CV) solutions. The results demonstrate that the silk fabrics corresponding to 0.3 and 0.4 mM of gold ions possess high SERS activity compared to the other treated fabrics. It is suggested that both the gold content and morphologies of gold nanoparticles dominate the SERS effect of the treated silk fabrics.

  4. Identifying strategies to assist final semester nursing students to develop numeracy skills: a mixed methods study.

    Science.gov (United States)

    Ramjan, Lucie M; Stewart, Lyn; Salamonson, Yenna; Morris, Maureen M; Armstrong, Lyn; Sanchez, Paula; Flannery, Liz

    2014-03-01

    It remains a grave concern that many nursing students within tertiary institutions continue to experience difficulties with achieving medication calculation competency. In addition, universities have a moral responsibility to prepare proficient clinicians for graduate practice. This requires risk management strategies to reduce adverse medication errors post registration. To identify strategies and potential predictors that may assist nurse academics to tailor their drug calculation teaching and assessment methods. This project builds on previous experience and explores students' perceptions of newly implemented interventions designed to increase confidence and competence in medication calculation. This mixed method study surveyed students (n=405) enrolled in their final semester of study at a large, metropolitan university in Sydney, Australia. Tailored, contextualised interventions included online practice quizzes, simulated medication calculation scenarios developed for clinical practice classes, contextualised 'pen and paper' tests, visually enhanced didactic remediation and 'hands-on' contextualised workshops. Surveys were administered to students to determine their perceptions of interventions and to identify whether these interventions assisted with calculation competence. Test scores were analysed using SPSS v. 20 for correlations between students' perceptions and actual performance. Qualitative open-ended survey questions were analysed manually and thematically. The study reinforced that nursing students preferred a 'hands-on,' contextualised approach to learning that was 'authentic' and aligned with clinical practice. Our interventions assisted with supporting students' learning and improvement of calculation confidence. Qualitative data provided further insight into students' awareness of their calculation errors and preferred learning styles. Some of the strongest predictors for numeracy skill performance included (1) being an international student, (2

  5. Theories of the Universe: A One Semester Course for Honors Undergraduates

    Science.gov (United States)

    Dimmock, John O.; Adams, Mitzi; Sever, Tom

    1999-01-01

    For the last two years The University of Alabama in Huntsville (UAH) has delivered a one semester course entitled Theories of The Universe as a seminar for undergraduate honors students. The enrollment is limited to fifteen students to encourage a maximum amount of interaction and discussion. The course has been team-taught enlisting the support of four scientists from the NASA Marshall Space Flight Center as well as UAH faculty from the history, philosophy, biology and physics departments. The course mixes history, mythology, philosophy, religion, and, of course, science and astronomy. The course traces mankind's view of the universe and how that has changed from about 30,000 years BCE to the current observations and models. Starting with a brief history of mankind we trace the evolution of ideas including Prehistoric European, Babylonian, Egyptian, Asian, North, Central and South American, African, Chinese, Greek, Middle Ages, Copernican, Galileo, Kepler, the Renaissance and Enlightenment, Newton, Einstein, and Hawking etc. Namely, we try to touch on just about every different view to puzzles of quantum cosmology, missing mass and the cosmological constant. By the end of the course, students should have a good understanding of: (1) the human desire and need for understanding; (2) the interplay between observations, modeling and theory development, and the need for revisions based on further observations; (3) the role of developing technology in advancing knowledge; (4) the evolution of our views of the universe and our relation to it; and (5) where we are today in our quest. Students are required to write two term papers and present them to the class. The final exam is a open discussion on our views of what we have learned.

  6. Surface-Enhanced Raman Scattering (SERS) for Detection in Immunoassays: applications, fundamentals, and optimization

    International Nuclear Information System (INIS)

    Jeremy Daniel Driskell

    2006-01-01

    Immunoassays have been utilized for the detection of biological analytes for several decades. Many formats and detection strategies have been explored, each having unique advantages and disadvantages. More recently, surface-enhanced Raman scattering (SERS) has been introduced as a readout method for immunoassays, and has shown great potential to meet many key analytical figures of merit. This technology is in its infancy and this dissertation explores the diversity of this method as well as the mechanism responsible for surface enhancement. Approaches to reduce assay times are also investigated. Implementing the knowledge gained from these studies will lead to a more sensitive immunoassay requiring less time than its predecessors. This dissertation is organized into six sections. The first section includes a literature review of the previous work that led to this dissertation. A general overview of the different approaches to immunoassays is given, outlining the strengths and weaknesses of each. Included is a detailed review of binding kinetics, which is central for decreasing assay times. Next, the theoretical underpinnings of SERS is reviewed at its current level of understanding. Past work has argued that surface plasmon resonance (SPR) of the enhancing substrate influences the SERS signal; therefore, the SPR of the extrinsic Raman labels (ERLs) utilized in our SERS-based immunoassay is discussed. Four original research chapters follow the Introduction, each presented as separate manuscripts. Chapter 2 modifies a SERS-based immunoassay previously developed in our group, extending it to the low-level detection of viral pathogens and demonstrating its versatility in terms of analyte type, Chapter 3 investigates the influence of ERL size, material composition, and separation distance between the ERLs and capture substrate on the SERS signal. This chapter links SPR with SERS enhancement factors and is consistent with many of the results from theoretical treatments

  7. Surface-Enhanced Raman Scattering (SERS) for Detection in Immunoassays. Applications, fundamentals, and optimization

    Energy Technology Data Exchange (ETDEWEB)

    Driskell, Jeremy Daniel [Iowa State Univ., Ames, IA (United States)

    2006-08-09

    Immunoassays have been utilized for the detection of biological analytes for several decades. Many formats and detection strategies have been explored, each having unique advantages and disadvantages. More recently, surface-enhanced Raman scattering (SERS) has been introduced as a readout method for immunoassays, and has shown great potential to meet many key analytical figures of merit. This technology is in its infancy and this dissertation explores the diversity of this method as well as the mechanism responsible for surface enhancement. Approaches to reduce assay times are also investigated. Implementing the knowledge gained from these studies will lead to a more sensitive immunoassay requiring less time than its predecessors. This dissertation is organized into six sections. The first section includes a literature review of the previous work that led to this dissertation. A general overview of the different approaches to immunoassays is given, outlining the strengths and weaknesses of each. Included is a detailed review of binding kinetics, which is central for decreasing assay times. Next, the theoretical underpinnings of SERS is reviewed at its current level of understanding. Past work has argued that surface plasmon resonance (SPR) of the enhancing substrate influences the SERS signal; therefore, the SPR of the extrinsic Raman labels (ERLs) utilized in our SERS-based immunoassay is discussed. Four original research chapters follow the Introduction, each presented as separate manuscripts. Chapter 2 modifies a SERS-based immunoassay previously developed in our group, extending it to the low-level detection of viral pathogens and demonstrating its versatility in terms of analyte type, Chapter 3 investigates the influence of ERL size, material composition, and separation distance between the ERLs and capture substrate on the SERS signal. This chapter links SPR with SERS enhancement factors and is consistent with many of the results from theoretical treatments

  8. Mol - Research Division Report 1986 - 2

    International Nuclear Information System (INIS)

    Delbarre, J.

    1987-03-01

    This report covers the research activities carried out at the SCK-CEN, Mol during the second semester of 1986. It deals with chemistry, chemical engineering, biology, nuclear metrology, analytical chemistry. (MCB)

  9. Mol - Research Division report 1987 - 2

    International Nuclear Information System (INIS)

    Delbarre, J.

    1988-03-01

    This report covers the research activities at the SCK-CEN, MOl, during the second semester of 1987. It deals with materials physics, nuclear physics, metallurgy, ceramics, nuclear chemistry, chemical engineering, biology, nuclear metrology and analytical chemistry. (MCB)

  10. Mol - Research Division report 1987 - 1

    International Nuclear Information System (INIS)

    Delbarre, J.

    1987-10-01

    This report covers the research activities at the SCK-CEN, Mol, during the first semester of 1987. It deals with material physics, nuclear physics, metallurgy, ceramics, nuclear chemistry, chemical engineering, biology, nuclear metrology and analytical chemistry. (MCB)

  11. Microfluidic setup for on-line SERS monitoring using laser induced nanoparticle spots as SERS active substrate

    Directory of Open Access Journals (Sweden)

    Oana-M. Buja

    2017-01-01

    Full Text Available A microfluidic setup which enables on-line monitoring of residues of malachite green (MG using surface-enhanced Raman scattering (SERS is reported. The SERS active substrate was prepared via laser induced synthesis of silver or gold nanoparticles spot on the bottom of a 200 μm inner dimension glass capillary, by focusing the laser beam during a continuous flow of a mixture of silver nitrate or gold chloride and sodium citrate. The described microfluidic setup enables within a few minutes the monitoring of several processes: the synthesis of the SERS active spot, MG adsorption to the metal surface, detection of the analyte when saturation of the SERS signal is reached, and finally, the desorption of MG from the spot. Moreover, after MG complete desorption, the regeneration of the SERS active spot was achieved. The detection of MG was possible down to 10−7 M concentration with a good reproducibility when using silver or gold spots as SERS substrate.

  12. SERS substrates for in-situ biosensing (Conference Presentation)

    Science.gov (United States)

    Venugopalan, Priyamvada; Quilis, Nestor; Jakub, Dostalek; Wolfgang, Knoll

    2017-06-01

    Abstract: Recent years have seen a rapid progress in the field of surface-enhanced Raman spectroscopy (SERS) which is attributed to the thriving field of plasmonics [1]. SERS is a susceptible technique that can address basic scientific questions and technological problems. In both cases, it is highly dependent upon the plasmonic substrate, where excitation of the localized surface plasmon resonance enhances the vibrational scattering signal of the analyte molecules adsorbed on to the surface [2]. In this work, using finite difference time domain (FDTD) method we investigate the optical properties of plasmonic nanostructures with tuned plasmonic resonances as a function of dielectric environment and geometric parameters. An optimized geometry will be discussed based on the plasmonic resonant position and the SERS intensity. These SERS substrates will be employed for the detection of changes in conformation caused by interactions between an aptamer and analyte molecules. This will be done by using a microfluidic channel designed within the configuration of the lab-on-a-chip concept based on the intensity changes of the SERS signal. More efficient and reproducible results are obtained for such a quantitative measurement of analytes at low concentration levels. We will also demonstrate that the plasmonic substrates fabricated by top down approach such as e-beam lithography (EBL) and laser interference lithography (LIL) are highly reproducible, robust and can result in high electric field enhancement. Our results demonstrate the potential to use SERS substrates for highly sensitive detection schemes opening up the window for a wide range of applications including biomedical diagnostics, forensic investigation etc. Acknowledgement: This work was supported by the Austrian Science Fund (FWF), project NANOBIOSENSOR (I 2647). References: [1] J. N. Anker, W. P. Hall, O. Lyandres, N. C. Shah, J. Zhao and R. P. V. Duyne., " Biosensing with plasmonic nanosensors," Nature

  13. Potential application of SERS for arsenic speciation in biological matrices.

    Science.gov (United States)

    Yang, Mingwei; Matulis, Shannon; Boise, Lawrence H; McGoron, Anthony J; Cai, Yong

    2017-08-01

    Speciation of arsenic is usually carried out using chromatography-based methods coupled with spectroscopic determination; however, the inevitable procedures involving sample preparation and separation could potentially alter the integrity of the arsenic metabolites present in biological samples. Surface-enhanced Raman spectroscopy (SERS) could be a promising alternative for providing a reliable arsenic analysis under the influence of a cellular matrix. A method for arsenic speciation using SERS in cellular matrix was developed in this study and four arsenicals were selected, including arsenite (As III ), arsenate (As V ), monomethylarsonic acid (MMA V ) and dimethylarsinic acid (DMA V ). Silver nanoparticles in the form of colliodal suspension with different surface charges, i.e., coated with citrate (AgNPs-Citrate) and spermine (AgNPs-Spermine) were employed as SERS substrates. Adsorption of arsenicals on nanoparticles in colloidal suspensions and the cellular matrix and the pH, size, and zeta potential of the colloidal suspensions were investigated for a better understanding of the SERS signal response of arsenicals in the colloidal suspensions or under the influence of cellular matrix. Arsenicals showed substantially different SERS responses in the two colloidal suspensions, mainly because of the distinct difference in the interaction between the arsenicals and the nanoparticles. Arsenic speciation in cell lysate could be successfully carried out in AgNPs-Spermine suspension, while AgNPs-Citrate could not yield significant SERS signals under the experimental conditions. This study proved that AgNPs-Spermine colloidal suspension could be a promising SERS substrate for studying arsenic metabolism in a biological matrix, reducing the bias caused by traditional techniques that involve sample extraction and pretreatment.

  14. A Framework to Manage through Control and Automation a semester long student Project assignment in e-Learning Environment

    OpenAIRE

    Chaumun, Mamade Ajmal

    2013-01-01

    Managing semester-long project assignments is not always an easy task since teachers need to keep track of many elements of the project that will reflect in a proper assessment of the students’ work. Integrating an LMS into the educational process and therefore to assign, track, and assess the project may add to the complication, this can be very challenging and especially when students work in groups. Students expect support and guidance from teachers in all stages of the project...

  15. SERS activity of Ag decorated nanodiamond and nano-β-SiC, diamond-like-carbon and thermally annealed diamond thin film surfaces.

    Science.gov (United States)

    Kuntumalla, Mohan Kumar; Srikanth, Vadali Venkata Satya Siva; Ravulapalli, Satyavathi; Gangadharini, Upender; Ojha, Harish; Desai, Narayana Rao; Bansal, Chandrahas

    2015-09-07

    In the recent past surface enhanced Raman scattering (SERS) based bio-sensing has gained prominence owing to the simplicity and efficiency of the SERS technique. Dedicated and continuous research efforts have been made to develop SERS substrates that are not only stable, durable and reproducible but also facilitate real-time bio-sensing. In this context diamond, β-SiC and diamond-like-carbon (DLC) and other related thin films have been promoted as excellent candidates for bio-technological applications including real time bio-sensing. In this work, SERS activities of nanodiamond, nano-β-SiC, DLC, thermally annealed diamond thin film surfaces were examined. DLC and thermally annealed diamond thin films were found to show SERS activity without any metal nanostructures on their surfaces. The observed SERS activities of the considered surfaces are explained in terms of the electromagnetic enhancement mechanism and charge transfer resonance process.

  16. Sensory experience ratings (SERs) for 1,659 French words: Relationships with other psycholinguistic variables and visual word recognition.

    Science.gov (United States)

    Bonin, Patrick; Méot, Alain; Ferrand, Ludovic; Bugaïska, Aurélia

    2015-09-01

    We collected sensory experience ratings (SERs) for 1,659 French words in adults. Sensory experience for words is a recently introduced variable that corresponds to the degree to which words elicit sensory and perceptual experiences (Juhasz & Yap Behavior Research Methods, 45, 160-168, 2013; Juhasz, Yap, Dicke, Taylor, & Gullick Quarterly Journal of Experimental Psychology, 64, 1683-1691, 2011). The relationships of the sensory experience norms with other psycholinguistic variables (e.g., imageability and age of acquisition) were analyzed. We also investigated the degree to which SER predicted performance in visual word recognition tasks (lexical decision, word naming, and progressive demasking). The analyses indicated that SER reliably predicted response times in lexical decision, but not in word naming or progressive demasking. The findings are discussed in relation to the status of SER, the role of semantic code activation in visual word recognition, and the embodied view of cognition.

  17. A SERS protocol as a potential tool to access 6-mercaptopurine release accelerated by glutathione-S-transferase.

    Science.gov (United States)

    Wang, Ying; Sun, Jie; Yang, Qingran; Lu, Wenbo; Li, Yan; Dong, Jian; Qian, Weiping

    2015-11-21

    The developed method for monitoring GST, an important drug metabolic enzyme, could greatly facilitate researches on relative biological fields. In this work, we have developed a SERS technique to monitor the absorbance behaviour of 6-mercaptopurine (6-MP) and its glutathione-S-transferase (GST)-accelerated glutathione (GSH)-triggered release behaviour on the surface of gold nanoflowers (GNFs), using the GNFs as excellent SERS substrates. The SERS signal was used as an indicator of absorbance or release of 6-MP on the gold surface. We found that GST can accelerate GSH-triggered release behaviour of 6-MP from the gold surface. We speculated that GST catalyzes nucleophilic GSH to competitively bind with the electrophilic substance 6-MP. Experimental results have proved that the presented SERS protocol can be utilized as an effective tool for accessing the release of anticancer drugs.

  18. SERS Detection of Penicillin G Using Magnetite Decorated with Gold Nanoparticles

    Directory of Open Access Journals (Sweden)

    Paula C. Pinheiro

    2017-10-01

    Full Text Available Sensitive and reliable procedures for detecting vestigial antibiotics are of great relevance for water quality monitoring due to the occurrence of such emergent pollutants in the aquatic environment. As such, we describe here research concerning the use of multifunctional nanomaterials combining magnetic and plasmonic components. These nanomaterials have been prepared by decorating magnetite nanoparticles (MNP with colloidal gold nanoparticles (Au NPs of distinct particle size distributions. Several analytical conditions were investigated in order to optimize the surface enhanced Raman scattering (SERS detection of penicillin G (PG dissolved in water. In particular, the dependence of the SERS signal by using distinct sized Au NPs adsorbed at the MNP was investigated. Additionally, microscopic methods, including Raman confocal microscopy, were employed to characterize the SERS substrates and then to qualitatively detect penicillin G using such substrates. For example, magnetic–plasmonic nanocomposites can be employed for magnetically concentrate analyte molecules and their removal from solution. As a proof of concept, we applied magneto-plasmonic nanosorbents in the removal of aqueous penicillin G and demonstrate the possibility of SERS sensing this antibiotic.

  19. Nanostructured surfaces for analysis of anticancer drug and cell diagnosis based on electrochemical and SERS tools

    Science.gov (United States)

    El-Said, Waleed A.; Yoon, Jinho; Choi, Jeong-Woo

    2018-04-01

    Discovering new anticancer drugs and screening their efficacy requires a huge amount of resources and time-consuming processes. The development of fast, sensitive, and nondestructive methods for the in vitro and in vivo detection of anticancer drugs' effects and action mechanisms have been done to reduce the time and resources required to discover new anticancer drugs. For the in vitro and in vivo detection of the efficiency, distribution, and action mechanism of anticancer drugs, the applications of electrochemical techniques such as electrochemical cell chips and optical techniques such as surface-enhanced Raman spectroscopy (SERS) have been developed based on the nanostructured surface. Research focused on electrochemical cell chips and the SERS technique have been reviewed here; electrochemical cell chips based on nanostructured surfaces have been developed for the in vitro detection of cell viability and the evaluation of the effects of anticancer drugs, which showed the high capability to evaluate the cytotoxic effects of several chemicals at low concentrations. SERS technique based on the nanostructured surface have been used as label-free, simple, and nondestructive techniques for the in vitro and in vivo monitoring of the distribution, mechanism, and metabolism of different anticancer drugs at the cellular level. The use of electrochemical cell chips and the SERS technique based on the nanostructured surface should be good tools to detect the effects and action mechanisms of anticancer drugs.

  20. Progress in the Development of SERS-Active Substrates Based on Metal-Coated Porous Silicon.

    Science.gov (United States)

    Bandarenka, Hanna V; Girel, Kseniya V; Zavatski, Sergey A; Panarin, Andrei; Terekhov, Sergei N

    2018-05-21

    The present work gives an overview of the developments in surface-enhanced Raman scattering (SERS) with metal-coated porous silicon used as an active substrate. We focused this review on the research referenced to SERS-active materials based on porous silicon, beginning from the patent application in 2002 and enclosing the studies of this year. Porous silicon and metal deposition technologies are discussed. Since the earliest studies, a number of fundamentally different plasmonic nanostructures including metallic dendrites, quasi-ordered arrays of metallic nanoparticles (NPs), and metallic nanovoids have been grown on porous silicon, defined by the morphology of this host material. SERS-active substrates based on porous silicon have been found to combine a high and well-reproducible signal level, storage stability, cost-effective technology and handy use. They make it possible to identify and study many compounds including biomolecules with a detection limit varying from milli- to femtomolar concentrations. The progress reviewed here demonstrates the great prospects for the extensive use of the metal-coated porous silicon for bioanalysis by SERS-spectroscopy.

  1. Progress in the Development of SERS-Active Substrates Based on Metal-Coated Porous Silicon

    Directory of Open Access Journals (Sweden)

    Hanna V. Bandarenka

    2018-05-01

    Full Text Available The present work gives an overview of the developments in surface-enhanced Raman scattering (SERS with metal-coated porous silicon used as an active substrate. We focused this review on the research referenced to SERS-active materials based on porous silicon, beginning from the patent application in 2002 and enclosing the studies of this year. Porous silicon and metal deposition technologies are discussed. Since the earliest studies, a number of fundamentally different plasmonic nanostructures including metallic dendrites, quasi-ordered arrays of metallic nanoparticles (NPs, and metallic nanovoids have been grown on porous silicon, defined by the morphology of this host material. SERS-active substrates based on porous silicon have been found to combine a high and well-reproducible signal level, storage stability, cost-effective technology and handy use. They make it possible to identify and study many compounds including biomolecules with a detection limit varying from milli- to femtomolar concentrations. The progress reviewed here demonstrates the great prospects for the extensive use of the metal-coated porous silicon for bioanalysis by SERS-spectroscopy.

  2. Performance of first-year health sciences students in a large, diverse, multidisciplinary, first-semester, physiology service module.

    Science.gov (United States)

    Higgins-Opitz, Susan B; Tufts, Mark

    2014-06-01

    Health Science students at the University of KwaZulu-Natal perform better in their professional modules compared with their physiology modules. The pass rates of physiology service modules have steadily declined over the years. While a system is in place to identify "at-risk" students, it is only activated after the first semester. As a result, it is only from the second semester of their first year studies onward that at-risk students can be formally assisted. The challenge is thus to devise an appropriate strategy to identify struggling students earlier in the semester. Using questionnaires, students were asked about attendance, financing of their studies, and relevance of physiology. After the first class test, failing students were invited to complete a second questionnaire. In addition, demographic data were also collected and analyzed. Correlation analyses were undertaken of performance indicators based on the demographical data collected. The 2011 class comprised mainly sport science students (57%). The pass rate of sport science students was lower than the pass rates of other students (42% vs. 70%, P physiology and recognized its relevance. Key issues identified were problems understanding concepts and terminology, poor study environment and skills, and lack of matriculation biology. The results of the first class test and final module marks correlated well. It is clear from this study that student performance in the first class test is a valuable tool to identify struggling students and that appropriate testing should be held as early as possible. Copyright © 2014 The American Physiological Society.

  3. Plasmonic crystal based solid substrate for biomedical application of SERS

    Science.gov (United States)

    Morasso, Carlo F.; Mehn, Dora; Picciolini, Silvia; Vanna, Renzo; Bedoni, Marzia; Gramatica, Furio; Pellacani, Paola; Frangolho, Ana; Marchesini, Gerardo; Valsesia, Andrea

    2014-02-01

    Surface Enhanced Raman Spectroscopy is a powerful analytical technique that combines the excellent chemical specificity of Raman spectroscopy with the good sensitivity provided by the enhancement of the signal observed when a molecule is located on (or very close to) the surface of suitable nanostructured metallic materials. The availability of cheap, reliable and easy to use SERS substrates would pave the road to the development of bioanalytical tests that can be used in clinical practice. SERS, in fact, is expected to provide not only higher sensitivity and specificity, but also the simultaneous and markedly improved detection of several targets at the same time with higher speed compared to the conventional analytical methods. Here, we present the SERS activity of 2-D plasmonic crystals made by polymeric pillars embedded in a gold matrix obtained through the combination of soft-lithography and plasma deposition techniques on a transparent substrates. The use of a transparent support material allowed us to perform SERS detection from support side opening the possibility to use these substrates in combination with microfluidic devices. In order to demonstrate the potentialities for bioanalytical applications, we used our SERS active gold surface to detect the oxidation product of apomorphine, a well-known drug molecule used in Parkinson's disease which has been demonstrated being difficult to study by traditional HPLC based approaches.

  4. Normal Raman and SERS spectroscopy of the vitamin E

    International Nuclear Information System (INIS)

    Cai Tiantian; Gu Huaimin; Yuan Xiaojuan; Liu Fangfang

    2011-01-01

    In this study, surface-enhanced Raman scattering(SERS)spectra of vitamin E were obtained on colloidal silver(Ag). Alpha-(-) tocopherol which is the only form that is recognized to meet human requirements was selected to study. The analytes (±)- -tocopherol were dissolved in chloroform (CHCl 3 ) and the silver colloid was poured into the compound. Silver colloid was reduced by hydroxylamine hydrochloride. The analytes were the supernatant after standing the mixture for the reason that chloroform have no signals in surface-enhanced Raman scattering in the Ag colloid, and it would not affect the determination of the (±)- -tocopherol. The Normal Raman and SERS spectrum of Vitamin E were contrastively studied to realize how the vitamin E stuck to the silver nanoparticles. The results show the fat-soluble substances can be analysed by SERS. The spectra indicate that the molecules are adsorbed on the surface through the COO- groups by the simultaneous involvement of a and -type coordination. These results suggest some important criteria for consideration in SERS measurements and also provide important insights into the problem of predicting SERS activities for different fat-soluble substances.

  5. Normal Raman and SERS spectroscopy of the vitamin E

    Energy Technology Data Exchange (ETDEWEB)

    Cai Tiantian; Gu Huaimin; Yuan Xiaojuan; Liu Fangfang, E-mail: guhm@scnu.edu.cn [MOE Key Laboratory of Laser Life Science, College of Biophotonics, South China Normal University, 510631, Guangzhou (China)

    2011-01-01

    In this study, surface-enhanced Raman scattering(SERS)spectra of vitamin E were obtained on colloidal silver(Ag). Alpha-(-) tocopherol which is the only form that is recognized to meet human requirements was selected to study. The analytes ({+-})- -tocopherol were dissolved in chloroform (CHCl{sub 3}) and the silver colloid was poured into the compound. Silver colloid was reduced by hydroxylamine hydrochloride. The analytes were the supernatant after standing the mixture for the reason that chloroform have no signals in surface-enhanced Raman scattering in the Ag colloid, and it would not affect the determination of the ({+-})- -tocopherol. The Normal Raman and SERS spectrum of Vitamin E were contrastively studied to realize how the vitamin E stuck to the silver nanoparticles. The results show the fat-soluble substances can be analysed by SERS. The spectra indicate that the molecules are adsorbed on the surface through the COO- groups by the simultaneous involvement of a and -type coordination. These results suggest some important criteria for consideration in SERS measurements and also provide important insights into the problem of predicting SERS activities for different fat-soluble substances.

  6. Correlative SEM SERS for quantitative analysis of dimer nanoparticles.

    Science.gov (United States)

    Timmermans, F J; Lenferink, A T M; van Wolferen, H A G M; Otto, C

    2016-11-14

    A Raman microscope integrated with a scanning electron microscope was used to investigate plasmonic structures by correlative SEM-SERS analysis. The integrated Raman-SEM microscope combines high-resolution electron microscopy information with SERS signal enhancement from selected nanostructures with adsorbed Raman reporter molecules. Correlative analysis is performed for dimers of two gold nanospheres. Dimers were selected on the basis of SEM images from multi aggregate samples. The effect of the orientation of the dimer with respect to the polarization state of the laser light and the effect of the particle gap size on the Raman signal intensity is observed. Additionally, calculations are performed to simulate the electric near field enhancement. These simulations are based on the morphologies observed by electron microscopy. In this way the experiments are compared with the enhancement factor calculated with near field simulations and are subsequently used to quantify the SERS enhancement factor. Large differences between experimentally observed and calculated enhancement factors are regularly detected, a phenomenon caused by nanoscale differences between the real and 'simplified' simulated structures. Quantitative SERS experiments reveal the structure induced enhancement factor, ranging from ∼200 to ∼20 000, averaged over the full nanostructure surface. The results demonstrate correlative Raman-SEM microscopy for the quantitative analysis of plasmonic particles and structures, thus enabling a new analytical method in the field of SERS and plasmonics.

  7. A semester-long soil mapping project for an undergraduate pedology course

    Science.gov (United States)

    Brown, David J.

    2015-04-01

    Most students taking a pedology course will never work as soil mappers. But many will use soil maps at some point in their careers. At Montana State University, students spent 3 "lab" hours a week, complementing two lectures a week, in the field learning how to study soils literally from the ground up. The only prerequisites for enrollment were completion of an introductory soil science class and 3rd year standing at the university. The area to be mapped, just a km from campus, included a steep mountain backslope, and a complex footslope-toeslope area with diverse soils. Students were divided into teams of 3-4, with approximately 40 students altogether split over two sections that overlapped in the field by one hour. In the first lab session, groups completed a very basic description of just one soil profile. In subsequent weeks, they rotated through multiple pits excavated in a small area, and expanded their soil profile descriptions and interpretations. As students developed proficiency, they were assigned more dispersed locations to study, working for the most part independently as I hiked between pits. Throughout this process, every pit was geolocated using a GPS unit, and every profile description was copied and retained in a designated class file. Student groups delineated map units using stereo air photography, then used these delineations to guide the selection of their final locations to describe. At the end of the course, groups used all of the combined and georeferenced profile descriptions to construct a soil map of the study area complete with map unit descriptions. Most students struggled to make sense of the substantial variability within their map units, but through this struggle -- and their semester of field work -- they gained an appreciation for the value and limitations of a soil map that could not be obtained from even the most entertaining lecture. Both the class and particularly the field sessions received consistently high student reviews

  8. Analysis of physical activity in emmetropic and myopic university students during semester and holiday periods: a pilot study.

    Science.gov (United States)

    Battersby, Katherine; Koy, Linda; Phillips, Nicola; Sim, Joanna; Wilk, Jay; Schmid, Katrina L

    2015-11-01

    Previous studies (mostly questionnaire-based in children) suggest that outdoor activity is protective against myopia. There are few studies on young adults investigating both the impact of simply being outdoors versus performing physical activity. The aim was to study the relationship between the refractive error of young adults and their physical activity patterns. Twenty-seven university students, aged 18 to 25 years, wore a pedometer (Omron HJ720ITE) for seven days both during the semester and holiday periods. They simultaneously recorded the type of activity performed, its duration, the number of steps taken (from the pedometer) and their location (indoors/outdoors) in a logbook. Mean spherical refractive error was used to divide participants into three groups (emmetropes: +1.00 to -0.50 D, low myopes: -0.62 to -3.00 D, higher myopes: -3.12 D or greater myopia). There were no significant differences between the refractive groups during the semester or holiday periods; the average daily times spent outdoors, the duration of physical activity, the ratio of physical activity performed outdoors to indoors and amount of near work performed were similar. The peak exercise intensity was similar across all groups: approximately 100 steps per minute, a brisk walk. Up to one-third of all physical activity was performed outdoors. There were some significant differences in activities performed during semester and holiday times. For example, low myopes spent significantly less time outside (49 ± 47 versus 74 ± 41 minutes, p = 0.005) and performed less physical activity (6,388 ± 1,747 versus 6,779 ± 2,746 steps per day; p = 0.03) during the holidays compared to during semester. The fact that all groups had similar low exercise intensity but many were not myopic suggests that physical activity levels are not critical. There were differences in the activity patterns of low myopes during semester and holiday periods. This study highlights the need for a larger longitudinal

  9. Ser lugar e ser território como experiências do ser-no-mundo: um exercício de existencialismo geográfico

    Directory of Open Access Journals (Sweden)

    Angelo Serpa

    2017-10-01

    Full Text Available Este ensaio busca aprofundar uma abordagem existencialista dos conceitos de lugar e território assumindo o pressuposto de que eles remetem, antes de tudo, a experiências geográficas que ora se distinguem, ora se aproximam e carregam em si a marca do espaço vivido. Para esta análise, parte-se do conceito de geograficidade – a base pré-consciente e pré-conceitual da geografia – assumindo também que, antes de qualquer conceituação ou estratégia de representação conceitual, as pessoas são seres essencialmente espaciais e que viver é produzir/experienciar espaço. O ensaio está dividido em seis seções: a introdução, uma problematização da dialética entre interior e exterior e seu desdobramento numa abordagem de como lugar e território se exprimem como modos geográficos de existência no espaço público; nas duas últimas seções, reflete-se sobre o papel do corpo nos processos de apropriação do espaço e sobre como ser lugar e ser território se exprimem como facetas do ser-no-mundo em seu sentido mais político.

  10. Highly Sensitive Filter Paper Substrate for SERS Trace Explosives Detection

    Directory of Open Access Journals (Sweden)

    Pedro M. Fierro-Mercado

    2012-01-01

    Full Text Available We report on a novel and extremely low-cost surface-enhanced Raman spectroscopy (SERS substrate fabricated depositing gold nanoparticles on common lab filter paper using thermal inkjet technology. The paper-based substrate combines all advantages of other plasmonic structures fabricated by more elaborate techniques with the dynamic flexibility given by the inherent nature of the paper for an efficient sample collection, robustness, and stability. We describe the fabrication, characterization, and SERS activity of our substrate using 2,4,6-trinitrotoluene, 2,4-dinitrotoluene, and 1,3,5-trinitrobenzene as analytes. The paper-based SERS substrates presented a high sensitivity and excellent reproducibility for analytes employed, demonstrating a direct application in forensic science and homeland security.

  11. SERS-based pesticide detection by using nanofinger sensors

    Science.gov (United States)

    Kim, Ansoon; Barcelo, Steven J.; Li, Zhiyong

    2015-01-01

    Simple, sensitive, and rapid detection of trace levels of extensively used and highly toxic pesticides are in urgent demand for public health. Surface-enhanced Raman scattering (SERS)-based sensor was designed to achieve ultrasensitive and simple pesticide sensing. We developed a portable sensor system composed of high performance and reliable gold nanofinger sensor strips and a custom-built portable Raman spectrometer. Compared to the general procedure and previously reported studies that are limited to laboratory settings, our analytical method is simple, sensitive, rapid, and cost-effective. Based on the SERS results, the chemical interaction of two pesticides, chlorpyrifos (CPF) and thiabendazole (TBZ), with gold nanofingers was studied to determine a fingerprint for each pesticide. The portable SERS-sensor system was successfully demonstrated to detect CPF and TBZ pesticides within 15 min with a detection limit of 35 ppt in drinking water and 7 ppb on apple skin, respectively.

  12. In Vitro and In Vivo SERS Biosensing for Disease Diagnosis

    Directory of Open Access Journals (Sweden)

    T. Joshua Moore

    2018-05-01

    Full Text Available For many disease states, positive outcomes are directly linked to early diagnosis, where therapeutic intervention would be most effective. Recently, trends in disease diagnosis have focused on the development of label-free sensing techniques that are sensitive to low analyte concentrations found in the physiological environment. Surface-enhanced Raman spectroscopy (SERS is a powerful vibrational spectroscopy that allows for label-free, highly sensitive, and selective detection of analytes through the amplification of localized electric fields on the surface of a plasmonic material when excited with monochromatic light. This results in enhancement of the Raman scattering signal, which allows for the detection of low concentration analytes, giving rise to the use of SERS as a diagnostic tool for disease. Here, we present a review of recent developments in the field of in vivo and in vitro SERS biosensing for a range of disease states including neurological disease, diabetes, cardiovascular disease, cancer, and viral disease.

  13. Measurement of elongational viscosity of polymer melts using SER Universal Testing Platform

    Czech Academy of Sciences Publication Activity Database

    Filip, Petr; Švrčinová, Petra

    2012-01-01

    Roč. 22, č. 1 (2012), s. 14776 ISSN 1430-6395 R&D Projects: GA ČR GA103/08/1307; GA ČR GA103/09/2066 Institutional research plan: CEZ:AV0Z20600510 Keywords : elongational viscosity * SER Universal Testing Platform * polymer melts * LDPE Subject RIV: BK - Fluid Dynamics Impact factor: 1.226, year: 2012 http://www.ar.ethz.ch/TMPPDF/23074299892.48/ApplRheol_22_14776.pdf

  14. Superhydrophobic SERS substrates based on silicon hierarchical nanostructures

    Science.gov (United States)

    Chen, Xuexian; Wen, Jinxiu; Zhou, Jianhua; Zheng, Zebo; An, Di; Wang, Hao; Xie, Weiguang; Zhan, Runze; Xu, Ningsheng; Chen, Jun; She, Juncong; Chen, Huanjun; Deng, Shaozhi

    2018-02-01

    Silicon nanostructures have been cultivated as promising surface enhanced Raman scattering (SERS) substrates in terms of their low-loss optical resonance modes, facile functionalization, and compatibility with today’s state-of-the-art CMOS techniques. However, unlike their plasmonic counterparts, the electromagnetic field enhancements induced by silicon nanostructures are relatively small, which restrict their SERS sensing limit to around 10-7 M. To tackle this problem, we propose here a strategy for improving the SERS performance of silicon nanostructures by constructing silicon hierarchical nanostructures with a superhydrophobic surface. The hierarchical nanostructures are binary structures consisted of silicon nanowires (NWs) grown on micropyramids (MPs). After being modified with perfluorooctyltriethoxysilane (PFOT), the nanostructure surface shows a stable superhydrophobicity with a high contact angle of ˜160°. The substrate can allow for concentrating diluted analyte solutions into a specific area during the evaporation of the liquid droplet, whereby the analytes are aggregated into a small volume and can be easily detected by the silicon nanostructure SERS substrate. The analyte molecules (methylene blue: MB) enriched from an aqueous solution lower than 10-8 M can be readily detected. Such a detection limit is ˜100-fold lower than the conventional SERS substrates made of silicon nanostructures. Additionally, the detection limit can be further improved by functionalizing gold nanoparticles onto silicon hierarchical nanostructures, whereby the superhydrophobic characteristics and plasmonic field enhancements can be combined synergistically to give a detection limit down to ˜10-11 M. A gold nanoparticle-functionalized superhydrophobic substrate was employed to detect the spiked melamine in liquid milk. The results showed that the detection limit can be as low as 10-5 M, highlighting the potential of the proposed superhydrophobic SERS substrate in

  15. SER Y ESTAR CON ADJETIVOS – SIGNIFICACION DE LAS PROPOSICIONES SER Y ESTAR CON ADJETIVOS – SIGNIFICACION DE LAS PROPOSICIONES

    Directory of Open Access Journals (Sweden)

    Javier García de María

    2008-07-01

    Full Text Available Ser y estar: uno de los temas difíciles de la enseñanza/aprendizaje del español. Este trabajo expone un enfoque que recurre a la significación como hilo conductor. Por una parte, a la significación de ser y de estar como verbos, en sí mismos. Por otra, a la significación de los adjetivos. El planteamiento no es ya qué significa un determinado adjetivo con ser o con estar, sino cuál de estos verbos puede expresar su significado único o cada uno de sus significados. Sobre esta base el análisis considera, primero, los significados de ser/estar y los significados de un adjetivo dado y, segundo, los resultados significativos que arroja la relación entre verbos y adjetivo. Cuando el significado de un adjetivo se pueda expresar con los dos verbos, la elección vendrá determinada por la intencionalidad del hablante en el contexto comunicativo en que se encuentre. A partir de aquí las construcciones en las que aparecen ser y estar son tratadas como proposiciones retórico-argumentativas.Ser and estar: a difficult aspect of Spanish as a foreign language. This essay presents an approach that takes signification as guide line. On the one hand, the signification of ser and estar for their own cause; on the other hand the signification of the adjectives. The question is no longer what the meaning of a given adjective is with ser or with estar, but with which of the two verbs is it possible to express the unique meaning or each of the meanings of that adjective. Starting from this basis the approach considers first, the isolated meanings of the verbs and of the adjectives and, second, the resultant signification out of the relation between the two sides. If the meaning of a given adjective can be expressed by both verbs, the selection of the verb is determined by the intentionality of the speaker in the communicative context in which he negotiates. From this background on the syntactical constructions in which ser and estar appear are treated as

  16. Fabrication of SERS Substrate by Multilayered Nanosphere Deposition Technique

    International Nuclear Information System (INIS)

    Fu, Chit Yaw; Dinish, U. S.; Praveen, Thoniyot; Koh, Zhen Yu; Kho, Khiang Wei; Malini, Olivo

    2010-01-01

    Metal film over nanosphere (MFON) has been employed as a reproducible and predictable SERS-active device in biosensing applications. In addition to its economic fabrication process, such substrate can be further processed to a prism-structure with increased SERS enhancement and wider Plasmon tunability. In this work, we investigate an alternative coating method to deposit a larger area of well-ordered PS beads with different sizes (oe = 100nm and 400 nm) onto a glass. The result suggests that the proposed well-coating technique can be suitably used to form closely-packed PS beads with diameter less than 100 nm for developing MFON substrates.

  17. LA GENÉTICA Y LA DIGNIDAD DEL SER HUMANO

    OpenAIRE

    Nicolás Jouve de Barreda

    2013-01-01

    Los elementos biológicos del hombre no son suficientes para afrontar las cuestiones bioéticas que se plantean en torno al concepto de persona, pero son necesarios para definir con precisión las propiedades de los seres humanos y los aspectos teológicos, filosóficos y jurídicos que son atribuibles a cada persona. El ser humano es un ser singular. En él que conviven dos dimensiones de distinta naturaleza, una material y otra espiritual, y precisamente esta es la principal de las diferencias en...

  18. SERS Raman Sensor Based on Diameter-Modulated Sapphire Fiber

    Energy Technology Data Exchange (ETDEWEB)

    Shimoji, Yutaka

    2010-08-09

    Surface enhanced Raman scattering (SERS) has been observed using a sapphire fiber coated with gold nano-islands for the first time. The effect was found to be much weaker than what was observed with a similar fiber coated with silver nanoparticles. Diameter-modulated sapphire fibers have been successfully fabricated on a laser heated pedestal growth system. Such fibers have been found to give a modest increase in the collection efficiency of induced emission. However, the slow response of the SERS effect makes it unsuitable for process control applications.

  19. New nanocomposites for SERS studies of living cells and mitochondria

    DEFF Research Database (Denmark)

    Sarycheva, A. S.; Brazhe, N. A.; Baizhumanov, A. A.

    2016-01-01

    A great enhancement in Raman scattering (SERS) from heme-containing submembrane biomolecules inside intact erythrocytes and functional mitochondria is demonstrated for the first time using silver–silica beads prepared using a new method involving aerosol pyrolysis with aqueous diamminesilver...... molecules. The SERS spectra of functional mitochondria are sensitive to the activity of the mitochondrial electron transport chain, thus making the method a novel label-free approach to monitor the redox state and conformation of cytochromes in their natural cell environment. The developed nanocomposites...

  20. Subnanomolar Sensitivity of Filter Paper-Based SERS Sensor for Pesticide Detection by Hydrophobicity Change of Paper Surface.

    Science.gov (United States)

    Lee, Minwoo; Oh, Kyudeok; Choi, Han-Kyu; Lee, Sung Gun; Youn, Hye Jung; Lee, Hak Lae; Jeong, Dae Hong

    2018-01-26

    As a cost-effective approach for detecting trace amounts of pesticides, filter paper-based SERS sensors have been the subject of intensive research. One of the hurdles to overcome is the difficulty of retaining nanoparticles on the surface of the paper because of the hydrophilic nature of the cellulose fibers in paper. This reduces the sensitivity and reproducibility of paper-based SERS sensors due to the low density of nanoparticles and short retention time of analytes on the paper surface. In this study, filter paper was treated with alkyl ketene dimer (AKD) to modify its property from hydrophilic to hydrophobic. AKD treatment increased the contact angle of the aqueous silver nanoparticle (AgNP) dispersion, which consequently increased the density of AgNPs. The retention time of the analyte was also increased by preventing its rapid absorption into the filter paper. The SERS signal was strongly enhanced by the increased number of SERS hot spots owing to the increased density of AgNPs on a small contact area of the filter surface. The reproducibility and sensitivity of the SERS signal were optimized by controlling the distribution of AgNPs on the surface of the filter paper by adjusting the concentration of the AgNP solution. Using this SERS sensor with a hydrophobicity-modified filter paper, the spot-to-spot variation of the SERS intensity of 25 spots of 4-aminothiophenol was 6.19%, and the limits of detection of thiram and ferbam as test pesticides were measured to be 0.46 nM and 0.49 nM, respectively. These proof-of-concept results indicate that this paper-based SERS sensor can serve for highly sensitive pesticide detection with low cost and easy fabrication.

  1. Visualization of elongation measurements using an SER universal testing platform

    Czech Academy of Sciences Publication Activity Database

    Pivokonský, Radek; Filip, Petr; Zelenková, Jana

    2015-01-01

    Roč. 25, č. 1 (2015), s. 1-8 ISSN 1430-6395 R&D Projects: GA ČR(CZ) GAP105/11/2342 Institutional support: RVO:67985874 Keywords : elongational viscosity * Universal Testing Platform (SER) * polymer melts * LDPE Subject RIV: BK - Fluid Dynamics Impact factor: 1.241, year: 2015

  2. BACH1 Ser919Pro variant and breast cancer risk

    Directory of Open Access Journals (Sweden)

    Eerola Hannaleena

    2006-01-01

    Full Text Available Abstract Background BACH1 (BRCA1-associated C-terminal helicase 1; also known as BRCA1-interacting protein 1, BRIP1 is a helicase protein that interacts in vivo with BRCA1, the protein product of one of the major genes for hereditary predisposition to breast cancer. Previously, two BACH1 germ line missense mutations have been identified in early-onset breast cancer patients with and without family history of breast and ovarian cancer. In this study, we aimed to evaluate whether there are BACH1 genetic variants that contribute to breast cancer risk in Finland. Methods The BACH1 gene was screened for germ line alterations among probands from 43 Finnish BRCA1/2 negative breast cancer families. Recently, one of the observed common variants, Ser-allele of the Ser919Pro polymorphism, was suggested to associate with an increased breast cancer risk, and was here evaluated in an independent, large series of 888 unselected breast cancer patients and in 736 healthy controls. Results Six BACH1 germ line alterations were observed in the mutation analysis, but none of these were found to associate with the cancer phenotype. The Val193Ile variant that was seen in only one family was further screened in an independent series of 346 familial breast cancer cases and 183 healthy controls, but no additional carriers were observed. Individuals with the BACH1 Ser919-allele were not found to have an increased breast cancer risk when the Pro/Ser heterozygotes (OR 0.90; 95% CI 0.70–1.16; p = 0.427 or Ser/Ser homozygotes (OR 1.02; 95% CI 0.76–1.35; p = 0.91 were compared to Pro/Pro homozygotes, and there was no association of the variant with any breast tumor characteristics, age at cancer diagnosis, family history of cancer, or survival. Conclusion Our results suggest that the BACH1 Ser919 is not a breast cancer predisposition allele in the Finnish study population. Together with previous studies, our results also indicate that although some rare germ line variants

  3. BACH1 Ser919Pro variant and breast cancer risk

    International Nuclear Information System (INIS)

    Vahteristo, Pia; Yliannala, Kristiina; Tamminen, Anitta; Eerola, Hannaleena; Blomqvist, Carl; Nevanlinna, Heli

    2006-01-01

    BACH1 (BRCA1-associated C-terminal helicase 1; also known as BRCA1-interacting protein 1, BRIP1) is a helicase protein that interacts in vivo with BRCA1, the protein product of one of the major genes for hereditary predisposition to breast cancer. Previously, two BACH1 germ line missense mutations have been identified in early-onset breast cancer patients with and without family history of breast and ovarian cancer. In this study, we aimed to evaluate whether there are BACH1 genetic variants that contribute to breast cancer risk in Finland. The BACH1 gene was screened for germ line alterations among probands from 43 Finnish BRCA1/2 negative breast cancer families. Recently, one of the observed common variants, Ser-allele of the Ser919Pro polymorphism, was suggested to associate with an increased breast cancer risk, and was here evaluated in an independent, large series of 888 unselected breast cancer patients and in 736 healthy controls. Six BACH1 germ line alterations were observed in the mutation analysis, but none of these were found to associate with the cancer phenotype. The Val193Ile variant that was seen in only one family was further screened in an independent series of 346 familial breast cancer cases and 183 healthy controls, but no additional carriers were observed. Individuals with the BACH1 Ser919-allele were not found to have an increased breast cancer risk when the Pro/Ser heterozygotes (OR 0.90; 95% CI 0.70–1.16; p = 0.427) or Ser/Ser homozygotes (OR 1.02; 95% CI 0.76–1.35; p = 0.91) were compared to Pro/Pro homozygotes, and there was no association of the variant with any breast tumor characteristics, age at cancer diagnosis, family history of cancer, or survival. Our results suggest that the BACH1 Ser919 is not a breast cancer predisposition allele in the Finnish study population. Together with previous studies, our results also indicate that although some rare germ line variants in BACH1 may contribute to breast cancer development, the

  4. A Hybrid Integrated Laboratory and Inquiry-Based Research Experience: Replacing Traditional Laboratory Instruction with a Sustainable Student-Led Research Project

    Science.gov (United States)

    Hartings, Matthew R.; Fox, Douglas M.; Miller, Abigail E.; Muratore, Kathryn E.

    2015-01-01

    The Department of Chemistry at American University has replaced its junior- and senior-level laboratory curriculum with two, two-semester long, student-led research projects as part of the department's American Chemical Society-accredited program. In the first semester of each sequence, a faculty instructor leads the students through a set of…

  5. Undergraduate research: a case study

    NARCIS (Netherlands)

    Koppelman, Hermannus; van Dijk, Elisabeth M.A.G.; van der Hoeven, Gerrit

    This paper describes a one semester research course for undergraduates of computing programs. Students formulate a research proposal, conduct research and write a full paper. They present the results at a one-day student conference. On the one hand we offer the students a lot of structure and

  6. Web-Based Alcohol Intervention in First-Year College Students: Efficacy of Full-Program Administration Prior to Second Semester.

    Science.gov (United States)

    Gilbertson, Rebecca J; Norton, Tina R; Beery, Susan H; Lee, Kassandra R

    2018-05-12

    Commercially available, web-based interventions for the prevention of alcohol use are being adopted for universal use with first-year college students, yet few have received empirical evaluation. This randomized controlled trial investigated the effectiveness of a novel, commercially available, personalized web-based alcohol intervention, Alcohol-Wise (version 4.0, 3 rd Millennium Classrooms), on multiple measures of alcohol consumption, alcohol consequences, alcohol expectancies, academic achievement, and adaptation to college in first-year students. Participants received Alcohol-Wise either prior to first semester or were waitlisted and received the intervention second semester. As longitudinal effectiveness was of interest, follow-up surveys were conducted 10 weeks (n = 76) and 24 weeks (n = 64) following the web-based alcohol intervention. Completion of Alcohol-Wise had effects on academic achievement. Specifically, at the 24 week follow-up, academic achievement was higher in participants who received the intervention first semester of their freshman year as compared to the waitlist control. The incremental rise in heavy episodic drinking during the first semester of college was also reduced in waitlisted participants by Alcohol-Wise administration prior to second semester. Conclusion/Importance: Implications for the timing of web-based alcohol interventions to include administration prior to both first and second semesters of the freshman year are discussed.

  7. Processing ser and estar to locate objects and events

    Science.gov (United States)

    Dussias, Paola E.; Contemori, Carla; Román, Patricia

    2016-01-01

    In Spanish locative constructions, a different form of the copula is selected in relation to the semantic properties of the grammatical subject: sentences that locate objects require estar while those that locate events require ser (both translated in English as ‘to be’). In an ERP study, we examined whether second language (L2) speakers of Spanish are sensitive to the selectional restrictions that the different types of subjects impose on the choice of the two copulas. Twenty-four native speakers of Spanish and two groups of L2 Spanish speakers (24 beginners and 18 advanced speakers) were recruited to investigate the processing of ‘object/event + estar/ser’ permutations. Participants provided grammaticality judgments on correct (object + estar; event + ser) and incorrect (object + ser; event + estar) sentences while their brain activity was recorded. In line with previous studies (Leone-Fernández, Molinaro, Carreiras, & Barber, 2012; Sera, Gathje, & Pintado, 1999), the results of the grammaticality judgment for the native speakers showed that participants correctly accepted object + estar and event + ser constructions. In addition, while ‘object + ser’ constructions were considered grossly ungrammatical, ‘event + estar’ combinations were perceived as unacceptable to a lesser degree. For these same participants, ERP recording time-locked to the onset of the critical word ‘en’ showed a larger P600 for the ser predicates when the subject was an object than when it was an event (*La silla es en la cocina vs. La fiesta es en la cocina). This P600 effect is consistent with syntactic repair of the defining predicate when it does not fit with the adequate semantic properties of the subject. For estar predicates (La silla está en la cocina vs. *La fiesta está en la cocina), the findings showed a central-frontal negativity between 500–700 ms. Grammaticality judgment data for the L2 speakers of Spanish showed that beginners were significantly less

  8. Using Action Research to Teach Students to Manage Team Learning and Improve Teamwork Satisfaction

    Science.gov (United States)

    Scott-Ladd, Brenda; Chan, Christopher C. A.

    2008-01-01

    This article reports on a study investigating strategies that students can use to develop skills in managing team learning. Two groups of second-year management students participated in a semester-long action research project over two semesters. The students were educated on team development, team processes and conflict management and how to…

  9. Ser649 and Ser650 are the major determinants of protein kinase A-mediated activation of human hormone-sensitive lipase against lipid substrates

    DEFF Research Database (Denmark)

    Krintel, Christian; Osmark, Peter; Larsen, Martin Røssel

    2008-01-01

    Hormone-sensitive lipase (HSL) is a key enzyme in the mobilization of fatty acids from stored triacylglycerols. Its activity is regulated by reversible protein phosphorylation. In rat HSL Ser563, Ser659 and Ser660 have been shown to be phosphorylated by protein kinase A (PKA) in vitro as well...

  10. Patchy silica-coated silver nanowires as SERS substrates

    Energy Technology Data Exchange (ETDEWEB)

    Hunyadi Murph, Simona E.; Murphy, Catherine J.

    2013-05-08

    We report a class of core-shell nanomaterials that can be used as efficient surface-enhancement Raman scattering (SERS) substrates. The core consists of silver nanowires, prepared through a chemical reduction process, that are used to capture 4- mercaptobenzoic acid (4-MBA), a model analyte. The shell was prepared through a modified Stöber method and consists of patchy or full silica coats. The formation of silica coats was monitored via transmission electron microscopy, UV-visible spectroscopy and phase-analysis light scattering for measuring effective surface charge. Surprisingly, the patchy silica coated silver nanowires are better SERS substrate than silver nanowires; nanomolar concentration of 4-MBA can be detected. In addition, “nano-matryoshka” configurations were used to quantitate/explore the effect of the electromagnetic field at the tips of the nanowire (“hot spots”) in the Raman scattering experiment.

  11. Applications of the surface enhanced Raman scattering (SERS)

    International Nuclear Information System (INIS)

    Picquart, M.; Haro P, E.; Bernard, S.

    2007-01-01

    Full text: Vibration spectroscopy techniques are used for many times to identify substances, determine molecular structure and quantify them, independently of their physical state. Raman spectroscopy as infrared absorption permit to access the vibration energy levels of molecules. In the second case, the permanent dipolar moment is involved while in the first one it is the polarizability (and the induced dipolar moment). Unfortunately, the classical Raman spectroscopy is low sensitive in particular in the case of biological molecules. On the opposite, the surface enhanced Raman spectroscopy (SERS) offers great potentialities. In this case, the molecules are adsorbed on a rough surface or on nanoparticles of gold or silver and the: signal can be increased by a factor of 10 7 to 10 8 . Moreover, the spectral enhancement is greater for the vibrations of the functional group of the molecule adsorbed on the substrate. In this work, we present the main theoretical bases of SERS, and some results obtain on different systems. (Author)

  12. Patchy silica-coated silver nanowires as SERS substrates

    International Nuclear Information System (INIS)

    Hunyadi Murph, Simona E.; Murphy, Catherine J.

    2013-01-01

    We report a class of core–shell nanomaterials that can be used as efficient surface-enhancement Raman scattering (SERS) substrates. The core consists of silver nanowires, prepared through a chemical reduction process, that are used to capture 4-mercaptobenzoic acid (4-MBA), a model analyte. The shell was prepared through a modified Stöber method and consists of patchy or full silica coats. The formation of silica coats was monitored via transmission electron microscopy, UV–visible spectroscopy, and phase-analysis light-scattering for measuring effective surface charge. Surprisingly, the patchy silica-coated silver nanowires are better SERS substrate than silver nanowires; nanomolar concentration of 4-MBA can be detected. In addition, “nano-matryoshka” configurations were used to quantitate/explore the effect of the electromagnetic field at the tips of the nanowire (“hot spots”) in the Raman scattering experiment.

  13. [TLC-FT-SERS study on ingredients of Isrhynchophylline].

    Science.gov (United States)

    Wang, Yuan; Wang, Song-ying; Zhao, Yi-xue; Ren, Gui-fen; Zi, Feng-lan

    2002-02-01

    A new method for analysing the ingredients of Isrhynchophylline in Uncaria Rhynchophylla Jacks by thin layer chromatography (TLC) and the surface-enhanced Raman spectroscopy (SERS) is reported in this paper. The results show that the characteristic spectra bands of Isrhynchophylline situated at the thin layer with the amount of sample about 2.5 micrograms were obtained. The difference between SERS and solid spectra was found. Great enhancement of the 1,615 cm-1 spectral band was abstained. Molecule was absorbed in surface silver sol by pi electrons in phenyl and by pair of electrons in N together. An absorption model of Isrhynchophylline and silver sol was proposed. This method can be used to analyse the chemical ingredients with high sensitivity.

  14. [TLC-SERS study on evodiamine in evodia rutaecarpa].

    Science.gov (United States)

    Zhang, Jin-zhi; Wang, Yuan; Chen, Hui; Shao, Hui-bo

    2007-05-01

    A new method for analyzing the ingredients of evodiamine (EV), rutaecarpine (RU), hydroxyevodiamine (HYD), evodiamide (ED), dihydrorutaecarpine (DRU) and 14-formyldihydrorutaecarpine (FDRU) in evodia rutaecarpa using high performance thin layer chromatography (TLC) and surface enhanced Raman spectroscopy (SERS) technique is reported. The character of this method is that standard samples are not needed. The results show that the characteristic spectral bands of EV, RU, HYD, and ED can be obtained from the TLC spot with microgramme of sample. The spectral band at 1562 cm(-1) was obtained with great enhancement. Molecule absorbed in surface silver sol by nr electrons in ring. The spectral bands of EV, RU, HYD and ED are obviously different due to their differences in structure. The TLC and SERS techniques standard samples are a convenient and speedy method to analyze chemical ingredients with high sensitivity for the study of the Chinese traditional medicine.

  15. Advanced Gas Sensors Using SERS-Activated Waveguides

    Science.gov (United States)

    Lascola, Robert; McWhorter, Scott; Murph, Simona Hunyadi

    2010-08-01

    This contribution describes progress towards the development and testing of a functionalized capillary that will provide detection of low-concentration gas-phase analytes through SERS. Measurement inside a waveguide allows interrogation of a large surface area, potentially overcoming the short distance dependence of the SERS effect. The possible use of Raman spectroscopy for gas detection is attractive for IR-inactive molecules or scenarios where infrared technology is inconvenient. However, the weakness of Raman scattering limits the use of the technique to situations where low detection limits are not required or large gas pressures are present. With surface-enhanced Raman spectroscopy (SERS), signal enhancements of 106 are often claimed, and higher values are seen in specific instances. However, most of the examples of SERS analysis are on liquid-phase samples, where the molecular density is high, usually combined with some sort of sample concentration at the surface. Neither of these factors is present in gas-phase samples. Because the laser is focused to a small point in the typical experimental setup, and the spatial extent of the effect above the surface is small (microns), the excitation volume is miniscule. Thus, exceptionally large enhancements are required to generate a signal comparable to that obtained by conventional Raman measurements. A reflective waveguide offers a way to increase the interaction volume of the laser with a SERS-modified surface. The use of a waveguide to enhance classical Raman measurements was recently demonstrated by S.M. Angel and coworkers, who obtained 12- to 30-fold sensitivity improvements for nonabsorbing gases (CO2, CH4) with a silvered capillary (no SERS enhancement). Shi et al.. demonstrated 10-to 100-fold enhancement of aqueous Rhodamine 6G in a capillary coated with silver nanoparticles. They observed enhancements of 10- to 100-fold compared to direct sampling, but this relied on a "double substrate", which required

  16. Synthesis, characterization and SERS activity of biosynthesized silver nanoparticles

    Science.gov (United States)

    Bindhu, M. R.; Sathe, V.; Umadevi, M.

    2013-11-01

    Silver nanoparticles were rapidly synthesized using Moringa oleifera flower extract as the reducing agent shows surface plasmon resonance peak at 439 nm. The size and shape of the nanoparticles controlled by varying the concentration of M. oleifera flower extract in the reaction medium. The synthesized silver nanoparticles were well-dispersed spherical nanoparticles with the average size of 14 nm. The retinoic acid present in M. oleifera flower extract used as reducing agent and proteins was responsible for capping of the bioreduced silver nanoparticles. The obtained nanoparticle shows size-dependent SERS activity. The SERS spectrum indicates that the pyridine adsorbed on the silver surface in a stand-on orientation via its nitrogen lone pair electrons.

  17. La polémica sobre el ser en el Avicena y Averroes latinos

    OpenAIRE

    García-Marqués, A. (Alfonso)

    1987-01-01

    Fiosofía medieval; recepción del aristotelismo árabe en Occidente; metafísica; aristotelismo platonizante; esencia; universal; accidentalidad del ser; ser y esencia; ser veritativo y ser extramental; crítica de Averroes a Avicena.

  18. General chemistry: expanding the learning outcomes and promoting interdisciplinary connections through the use of a semester-long project.

    Science.gov (United States)

    Wenzel, Thomas J

    2006-01-01

    The laboratory component of a first-semester general chemistry course for science majors is described. The laboratory involves a semester-long project undertaken in a small-group format. Students are asked to examine whether plants grown in soil contaminated with lead take up more lead than those grown in uncontaminated soil. They are also asked to examine whether the acidity of the rainwater affects the amount of lead taken up by the plants. Groups are then given considerable independence in the design and implementation of the experiment. Once the seeds are planted, which takes about 4 wk into the term, several shorter experiments are integrated in before it is time to harvest and analyze the plants. The use of a project and small working groups allows for the development of a broader range of learning outcomes than occurs in a "traditional" general chemistry laboratory. The nature of these outcomes and some of the student responses to the laboratory experience are described. This particular project also works well at demonstrating the connections among chemistry, biology, geology, and environmental studies.

  19. Expanding Applications of SERS through Versatile Nanomaterials Engineering (Postprint)

    Science.gov (United States)

    2017-06-22

    which form covalent metal–S bonds), amine, cyanide , and carboxylic acid functional groups; and their adsorption depends on solution pH and ionic...for some SERS sensing appli- cations, such as biosensing in complex biological fluids (where multiple molecules with primary amine and carboxylic acid...bonding interactions.33d,e Furthermore, mixed SAMs can take advantage of multiple types of interactions and build complexity into the surface chemistry

  20. Significado de ser docente para el adulto mayor sanfernandino

    OpenAIRE

    Martina, Martha; Santos, Gladys; Lema, Julia

    2013-01-01

    Objetivos: Comprender el significado de ser docente para el adulto mayor de la Facultad de Medicina de San Marcos y describir las motivaciones que determinan, de alguna forma, su decisión de postergar su retiro, no obstante haber cumplido con los requisitos legales para la jubilación. Diseño: Estudio de caso cualitativo. Institución: Facultad de Medicina, UNMSM. Participantes: Docentes adulto mayores de la Facultad de Medicina. Intervenciones: Entrevista a profundidad. Principales medidas de ...

  1. Development of chitosan-coated gold nanoflowers as SERS-active probes

    Science.gov (United States)

    Xu, Dan; Gu, Jiangjiang; Wang, Weina; Yu, Xuehai; Xi, Kai; Jia, Xudong

    2010-09-01

    Surface-enhanced Raman scattering (SERS) has been intensely researched for many years as a potential technique for highly sensitive detection. This work, through the reduction of HAuCl4 with pyrrole in aqueous solutions, investigated a facile one-pot synthesis of flower-like Au nanoparticles with rough surfaces. The formation process of the Au nanoflowers (AuNFs) was carefully studied, and a spontaneous assembly mechanism was proposed based on the time-course experimental results. The key synthesis strategy was to use pyrrole as a weak particle stabilizing and reducing agent to confine crystal growth in the limited ligand protection region. The nanometer-scale surface roughness of AuNFs provided several hot spots on a single particle, which significantly increased SERS enhancement. Good biocompatible stable Raman-active probes were synthesized by coating AuNFs with chitosan. The conservation of the SERS effects in living cells suggested that the chitosan-capped AuNFs could be suitable for highly sensitive detection and have potential for targeting of tumors in vivo.

  2. Laser in medicine Láser en medicina

    Directory of Open Access Journals (Sweden)

    Juan C. Cárdenas

    1993-03-01

    Full Text Available The fundamentals of laser functioning and a brief historic description on the subject are presented; laser Is classified according to emission potency, materials with which it is built and pulsation. Different mechanisms of action of laser as well as Its indications and contraindications are discussed. Emphasis is given to low-power laser. Local and foreign experiences with Its medlcal use are briefly described

    Se revisan los principios fundamentales del funcionamiento del láser, se hace una breve revisión histórica del mismo y se lo clasifica de acuerdo con la potencia de emisión, los materiales de fabricación y la pulsación. Se enumeran los diferentes mecanismos de acción del láser y sus indicaciones y contraindicaciones haciendo énfasis en lo concerniente al láser de baja potencia, tanto pulsado como no pulsado; se alude a las experiencias nacionales y de otros países.

  3. Interpenetrating polyaniline-gold electrodes for SERS and electrochemical measurements

    Science.gov (United States)

    West, R. M.; Semancik, S.

    2016-11-01

    Facile fabrication of nanostructured electrode arrays is critical for development of bimodal SERS and electrochemical biosensors. In this paper, the variation of applied potential at a polyaniline-coated Pt electrode is used to selectivity deposit Au on the polyaniline amine sites or on the underlying Pt electrode. By alternating the applied potential, the Au is grown simultaneously from the top and the bottom of the polyaniline film, leading to an interpenetrated, nanostructured polymer-metal composite extending from the Pt electrode to the electrolyte solution. The resulting films have unique pH-dependent electrochemical properties, e.g. they retain electrochemical activity in both acidic and neutral solutions, and they also include SERS-active nanostructures. By varying the concentration of chloroaurate used during deposition, Au nanoparticles, nanodendrites, or nanosheets can be selectively grown. For the films deposited under optimal conditions, using 5 mmol/L chloroaurate, the SERS enhancement factor for Rhodamine 6G was found to be as high as 1.1 × 106 with spot-to-spot and electrode-to-electrode relative standard deviations as low as 8% and 12%, respectively. The advantages of the reported PANI-Au composite electrodes lie in their facile fabrication, enabling the targeted deposition of tunable nanostructures on sensing arrays, and their ability to produce orthogonal optical and electrochemical analytical results.

  4. Surface modified gold nanoparticles for SERS based detection of vulnerable plaque formations (Conference Presentation)

    Science.gov (United States)

    Matthäus, Christian; Dugandžić, Vera; Weber, Karina; Cialla-May, Dana; Popp, Jürgen

    2017-02-01

    Cardiovascular diseases are the leading cause of death worldwide. Atherosclerosis is closely related to the majority of these diseases, as a process of thickening and stiffening of the arterial walls through accumulation of lipids, which is a consequence of aging and life style. Atherosclerosis affects all people in some extent, but not all arterial plaques will necessarily lead to the complications, such as thrombosis, stroke and heart attack. One of the greatest challenges in the risk assessment of atherosclerotic depositions is the detection and recognition of plaques which are unstable and prone to rupture. These vulnerable plaques usually consist of a lipid core that attracts macrophages, a type of white blood cells that are responsible for the degradation of lipids. It has been hypothesized that the amount of macrophages relates to the overall plaque stability. As phagocytes, macrophages also act as recipients for nanoscale particles or structures. Administered gold nanoparticles are usually rabidly taken up by macrophages residing within arterial walls and can therefore be indirectly detected. A very sensitive strategy for probing gold nanoparticles is by utilizing surface enhanced Raman scattering (SERS). By modifying the surface of these particles with SERS active labels it is possible to generate highly specific signals that exhibit sensitivity comparable to fluorescence. SERS labeled gold nanoparticles have been synthesized and the uptake dynamics and efficiency on macrophages in cell cultures was investigated using Raman microscopic imaging. The results clearly show that nanoparticles are taken up by macrophages and support the potential of SERS spectroscopy for the detection of vulnerable plaques. Acknowledgements: Financial support from the Carl Zeiss Foundation is highly acknowledged. The project "Jenaer Biochip Initiative 2.0" (03IPT513Y) within the framework "InnoProfile Transfer - Unternehmen Region" is supported by the Federal Ministry of

  5. Porous plasmonic nanocomposites for SERS substrates fabricated by two-step laser method

    Energy Technology Data Exchange (ETDEWEB)

    Koleva, M.E., E-mail: mihaela_ek@yahoo.com [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee blvd., Sofia 1784 (Bulgaria); International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044 (Japan); Nedyalkov, N.N.; Atanasov, P.A. [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee blvd., Sofia 1784 (Bulgaria); Gerlach, J.W.; Hirsch, D.; Prager, A.; Rauschenbach, B. [Leibniz Institute of Surface Modification (IOM), Permoserstrasse 15, D-04318 Leipzig (Germany); Fukata, N.; Jevasuwan, W. [International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044 (Japan)

    2016-04-25

    This research is focused on investigation of coupled plasmonic/metal-semiconductor nanomaterials. A two-step laser-assisted method is demonstrated for formation of plasmonic Ag nanoparticles (NPs) distributed into porous metal–oxide semiconductors. The mosaic Ag-ZnO target is used for laser ablation and, subsequently, laser annealing of the deposited layer is applied. The plasmon resonance properties of the nanostructures produced are confirmed by optical transmission spectroscopy. The wurtzite structure of ZnO is formed with tilted c-axis orientation and, respectively, a mixed Raman mode appears at 580 cm{sup −1}. The oxygen pressure applied during a deposition process has impact on the morphology and thickness of the porous nanostructures, but not on the size and size distribution of AgNPs. The porous nanocomposites exhibited potential for SERS applications, most pronounced for the oxygen deficient sample, grown at lower oxygen pressure. The observed considerable SERS enhancement of R6G molecules on AgNP/ZnO can be attributed to the ZnO-to-molecule charge transfer contribution, enhanced by the additional electrons from the local surface plasmon resonance (LSPR) of AgNPs to the ZnO through the conduction band. - Highlights: • Porous AgNPs/ZnO composites are obtained by laser deposition and laser annealing. • Morphology and properties depend on growth oxygen pressure. • The emergence of mixed-symmetry Raman mode at 580 cm{sup −1} is registered. • The AgNPs/ZnO porous nanocomposites are suitable for SERS-active substrates. • The charge transfer enhanced by LSPR has a contribution to SERS effect.

  6. Highly Sensitive and Reproducible SERS Sensor for Biological pH Detection Based on a Uniform Gold Nanorod Array Platform.

    Science.gov (United States)

    Bi, Liyan; Wang, Yunqing; Yang, Ying; Li, Yuling; Mo, Shanshan; Zheng, Qingyin; Chen, Lingxin

    2018-05-09

    Conventional research on surface-enhanced Raman scattering (SERS)-based pH sensors often depends on nanoparticle aggregation, whereas the variability in nanoparticle aggregation gives rise to poor repeatability in the SERS signal. Herein, we fabricated a gold nanorod array platform via an efficient evaporative self-assembly method. The platform exhibits great SERS sensitivity with an enhancement factor of 5.6 × 10 7 and maintains excellent recyclability and reproducibility with relative standard deviation (RSD) values of less than 8%. On the basis of the platform, we developed a highly sensitive bovine serum albumin (BSA)-coated 4-mercaptopyridine (4-MPy)-linked (BMP) SERS-based pH sensor to report pH ranging from pH 3.0 to pH 8.0. The intensity ratio variation of 1004 and 1096 cm -1 in 4-MPy showed excellent pH sensitivity, which decreased as the surrounding pH increased. Furthermore, this BMP SERS-based pH sensor was employed to measure the pH value in C57BL/6 mouse blood. We have demonstrated that the pH sensor has great advantages such as good stability, reliability, and accuracy, which could be extended for the design of point-of-care devices.

  7. Plasmonic nanoholes as SERS devices for biosensing applications: An easy route for nanostructures fabrication on glass substrates

    KAUST Repository

    Candeloro, Patrizio

    2016-12-26

    Surface enhanced Raman spectroscopy (SERS) has been largely exploited in the last decade for biochemical and biomedical research. But some issues still require attention before transferring SERS to bioclinical routinely practices, such as reproducibility, quantitative analysis and signal background interference. In this work we propose an easy and cheap route, based on a template stripping technique, for producing plasmonic nanostructured films with SERS capabilities. We focus our attention to nanoholes in a continuous gold film, conversely to the majority of the literature which is dealing with individual nanostructures. Plasmon resonances occur at the holes edges, thus enabling the possibility of SERS signals from biomolecules and the potential application as biosensors. One advantage of the nanoholes patterned film is the optical-subdiffraction pitch, which prevents any Raman and/or fluorescence signal arising from the bottom slide. This effect paves the way to standard glass slides, much cheaper than CaF2 ones, as suitable substrates for SERS devices, without any interfering signal coming from the glass itself.

  8. Leucipo, Demócrito e Kant: uma Reflexão sobre a Equivalência entre Ser e Não-Ser

    Directory of Open Access Journals (Sweden)

    Eberth Eleuterio dos Santos

    2015-08-01

    Full Text Available De início, apresentaremos a tese de Demócrito e Leucipo, segundo a qual o ser não é mais que o não-ser, tendo como contraponto o pensamento eleata acerca da inexistência necessária do não-ser. Esta discussão nos remete à oposição entre o pleno (cheio e o vazio que será posteriormente traduzida na oposição entre o ser e o nada (ou o não-ser. Desse modo, a oposição entre o pleno e o vazio é uma oposição que se desloca para o ser e o não-ser. Em seguida, faremos a apreciação do escrito pré-crítico kantiano Ensaio para introduzir em filosofia o conceito de grandeza negativa, no qual distinguimos certo tipo de oposição tomada entre grandezas em geral que, acreditamos, poderia ser interpretado como estando de acordo com o posicionamento de Demócrito e Leucipo sobre o estatuto ontológico do não-ser como princípio equivalente ao ser, e não como sua contradição em sentido puramente lógico.

  9. Researching with undergraduate students

    DEFF Research Database (Denmark)

    Wulf-Andersen, Trine Østergaard; Mogensen, Kevin; Hjort-Madsen, Peder

    2013-01-01

    The article presents a particular case of undergraduate students working on subprojects within the framework of their supervisors' (the authors') research project during Autumn Semester 2012 and Spring Semester 2013. The article's purpose is to show that an institutionalized focus on students...... as "research learners" rather than merely curriculum learners proves productive for both research and teaching. We describe the specific university learning context and the particular organization of undergraduate students' supervision and assistantships. The case builds on and further enhances a well......-established and proven university model of participant-directed, problem-oriented project work. We explore students' and researchers' experiences of being part of the collaboration, focusing on learning potentials and dilemmas associated with the multiple roles of researcher and student that characterized...

  10. SERS active systems of water-soluble polythiophene and plasmonic nanoparticles: preparation and optical properties

    Czech Academy of Sciences Publication Activity Database

    Kazim, Samrana; Pfleger, Jiří; Halašová, Klára; Procházka, M.; Bondarev, D.; Vohlídal, J.

    2011-01-01

    Roč. 55, č. 2 (2011), 23905_1-23905_6 ISSN 1286-0042. [International Symposium on Flexible Organic Electronics /3./. Ouranoupolis, 06.07.2010-09.07.2010] R&D Projects: GA AV ČR KAN100500652; GA MŠk 7E10040; GA ČR GAP208/10/0941 Institutional research plan: CEZ:AV0Z40500505 Keywords : nanocomposite * SERS * .pi.-conjugated polymer s Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.771, year: 2011

  11. Reduced graphene oxide wrapped Ag nanostructures for enhanced SERS activity

    Science.gov (United States)

    Nair, Anju K.; Kala, M. S.; Thomas, Sabu; Kalarikkal, Nandakumar

    2018-04-01

    Graphene - metal nanoparticle hybrids have received great attention due to their unique electronic properties, large specific surface area, very high conductivity and more charge transfer. Thus, it is extremely advantages to develop a simple and efficient process to disperse metal nanostructures over the surface of graphene sheets. Herein, we report a hydrothermal assisted strategy for developing reduced graphene oxide /Ag nanomorphotypes (cube, wire) for surface enhanced Raman scattering (SERS) applications, considering the advantages of synergistic effect of graphene and plasmonic properties of Ag nanomorphotypes.

  12. Silver coated aluminium microrods as highly colloidal stable SERS platforms.

    Science.gov (United States)

    Pazos-Perez, Nicolas; Borke, Tina; Andreeva, Daria V; Alvarez-Puebla, Ramon A

    2011-08-01

    We report on the fabrication of a novel material with the ability to remain in solution even under the very demanding conditions required for structural and dynamic characterization of biomacromolecule assays. This stability is provided by the increase in surface area of a low density material (aluminium) natively coated with a very hydrophilic surface composed of aluminium oxide (Al(2)O(3)) and metallic silver nanoparticles. Additionally, due to the dense collection of active hot spots on their surface, this material offers higher levels of SERS intensity as compared with the same free and aggregated silver nanoparticles. This journal is © The Royal Society of Chemistry 2011

  13. Impact of the Second Semester University Modeling Instruction Course on Students' Representation Choices

    Science.gov (United States)

    McPadden, Daryl; Brewe, Eric

    2017-01-01

    Representation use is a critical skill for learning, problem solving, and communicating in science, especially in physics where multiple representations often scaffold the understanding of a phenomenon. University Modeling Instruction, which is an active-learning, research-based introductory physics curriculum centered on students' use of…

  14. Compression of Semesters or Intensity of Study: What is it that Increases Student Success?

    Science.gov (United States)

    Spurling, Steven

    This study examined the relationship between intensity of study (defined as more hours per week of class within a subject matter area) and student success. The researcher identified two possible methods for increasing the intensity of study: (1) Compression Hypothesis--shortening the length of terms and increasing the amount of time per week spent…

  15. Bringing Reality T.V. into the Classroom: A Semester-Long Amazing Race

    Science.gov (United States)

    Weddell, Melissa S.

    2011-01-01

    In developing a more student centered and engaging approach to teaching an introductory tourism course, the reality television show "The Amazing Race" was incorporated into the curriculum. Students integrate book chapters and class lectures into researching how locations create tourism destinations through a series of ten weekly assignments. The…

  16. Prominent stylistic aspects in music of Nāser Khosrow's poetry

    Directory of Open Access Journals (Sweden)

    Morteza Mohseni

    2017-04-01

    Full Text Available It is axiomatic  for those who are stylistically a little familiar  about  the periods of  Persian  poetry  that  quasidas  of  Nāser-e Khosrow are totally  different  from  those  of  the  poets  in  fifth  lunar  century  both  in  terms  of  their  contents  and  technically.  This difference  is  seen  even  in  those  areas  of  his  poetry in which the poet is confided to make innovations. This paper investigates Nāser-e Khosrow's style in the field of the music of poetry. It also aims to identify his slylistic differences comparing with those of his most famous contemporaries (Onsori, Farrokhi and Manoochehri in external, lateral and internal areas.      As the first  step, all the Nāser Khosrow's poems -exept for additions section- was considered the Scope of this study, accompanied by main parts of other three cited  poets' divans (poetical works which consists almost 23600 distiches. For the second stage, each poet's divan were separatly scrutinized in three fields of the music of poetry. The frequency of each cases were recorded and after comparing statistics related to Nāser-e Khosrow's poems with other tree poets,  stylistic charachteristics of his poetry were explored. Statistical information related to the poets were generally recorded in a table and some parts of them were shown in a bar graph. It seems necessary to note that the researcher considered two items of  innovation and frequncy in all phases of the study.     Most of the studies done in the field of Nāser-e Khosrow's music of poetry, investigated the prosody and meter of his poetry. Most of these studies considered difficulty and relevancy as the important prosodic characteristics of  his poetry. Regarding the lateral and internal areas of Nāser-e Khosrow's poetry, there are not much argument proposed except for using difficult rhymes and nominal radifs ( for lateral music of poetry and attending to figures of

  17. Hierarchical Ag mesostructures for single particle SERS substrate

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Minwei, E-mail: xuminwei@xjtu.edu.cn; Zhang, Yin

    2017-01-30

    Highlights: • Hierarchical Ag mesostructures with the size of 250, 360 and 500 nm are synthesized via a seed-mediated approach. • The Ag mesostructures present the tailorable size and highly roughened surfaces. • The average enhancement factors for individual Ag mesostructures were estimated to be as high as 10{sup 6}. - Abstract: Hierarchical Ag mesostructures with highly rough surface morphology have been synthesized at room temperature through a simple seed-mediated approach. Electron microscopy characterizations indicate that the obtained Ag mesostructures exhibit a textured surface morphology with the flower-like architecture. Moreover, the particle size can be tailored easily in the range of 250–500 nm. For the growth process of the hierarchical Ag mesostructures, it is believed that the self-assembly mechanism is more reasonable rather than the epitaxial overgrowth of Ag seed. The oriented attachment of nanoparticles is revealed during the formation of Ag mesostructures. Single particle surface enhanced Raman spectra (sp-SERS) of crystal violet adsorbed on the hierarchical Ag mesostructures were measured. Results reveal that the hierarchical Ag mesostructures can be highly sensitive sp-SERS substrates with good reproducibility. The average enhancement factors for individual Ag mesostructures are estimated to be about 10{sup 6}.

  18. Superhydrophobic analyte concentration utilizing colloid-pillar array SERS substrates.

    Science.gov (United States)

    Wallace, Ryan A; Charlton, Jennifer J; Kirchner, Teresa B; Lavrik, Nickolay V; Datskos, Panos G; Sepaniak, Michael J

    2014-12-02

    The ability to detect a few molecules present in a large sample is of great interest for the detection of trace components in both medicinal and environmental samples. Surface enhanced Raman spectroscopy (SERS) is a technique that can be utilized to detect molecules at very low absolute numbers. However, detection at trace concentration levels in real samples requires properly designed delivery and detection systems. The following work involves superhydrophobic surfaces that have as a framework deterministic or stochastic silicon pillar arrays formed by lithographic or metal dewetting protocols, respectively. In order to generate the necessary plasmonic substrate for SERS detection, simple and flow stable Ag colloid was added to the functionalized pillar array system via soaking. Native pillars and pillars with hydrophobic modification are used. The pillars provide a means to concentrate analyte via superhydrophobic droplet evaporation effects. A ≥ 100-fold concentration of analyte was estimated, with a limit of detection of 2.9 × 10(-12) M for mitoxantrone dihydrochloride. Additionally, analytes were delivered to the surface via a multiplex approach in order to demonstrate an ability to control droplet size and placement for scaled-up uses in real world applications. Finally, a concentration process involving transport and sequestration based on surface treatment selective wicking is demonstrated.

  19. A Survey Tool for Assessing Student Expectations Early in a Semester

    Directory of Open Access Journals (Sweden)

    Karl R.B. Schmitt

    2013-08-01

    Full Text Available Quality learning is fostered when faculty members are aware of and address student expectations for course learning activities and assessments. However, faculty often have difficulty identifying and addressing student expectations given variations in students’ backgrounds, experiences, and beliefs about education. Prior research has described significant discrepancies between student and faculty expectations that result from cultural backgrounds (1, technological expertise (2, and ‘teaching dimensions’ as described by Trudeau and Barnes (4. Such studies illustrate the need for tools to identify and index student expectations, which can be used to facilitate a dialogue between instructor and students. Here we present the results of our work to develop, refine, and deploy such a tool.

  20. An association between apo-A4 gene polymorphism (Thr347Ser ...

    African Journals Online (AJOL)

    Pramod Kumar

    Objective: We aimed at studying the relationship between apoA4 gene polymorphisms (Thr347Ser and ... showed significant association with lipid risk factors like high levels of ..... in German population showed that Ser347 allele is associated.

  1. The Value of Collaborative Research before Independent Research in Undergraduate Music Education

    Science.gov (United States)

    Harney, Kristin

    2017-01-01

    Increasing evidence points to the importance of undergraduate research in teacher education programs. Before undertaking independent research, it is essential that music education students gain exposure to a range of research skills and develop basic research competencies. In this study, I explored the influence of a semester-long collaborative…

  2. Perception, awareness and practice of research-oriented medical education among undergraduate students of a medical college in Kolkata, West Bengal.

    Science.gov (United States)

    Chatterjee, Subhankar; Adhikari, Anjan; Haldar, Dibakar; Biswas, Payel

    2016-01-01

    The addition of research-oriented medical education (ROME) to the existing curriculum could promote logical thinking, rapid literature search and a better understanding of research methodology. Creation of research temperament could lead to innovations in healthcare. We assessed the perception, awareness and practice of ROME among undergraduate students. We conducted a cross-sectional survey among 234 students of R.G. Kar Medical College, Kolkata selected by the simple random sampling technique. Data were collected using a pre-designed, pre-tested, validated questionnaire by direct interviews. The mean (SD) perception score was 44.2 (5.03). Students from outside West Bengal (p=0.05), women (p=0.03) and students whose parents were doctors (p=0.01) had significantly higher scores. Students in the second and fourth semesters had a better perception than those in the sixth and eighth semesters. Awareness of research fellowships granted to undergraduate students such as the Indian Council of Medical Research-Short-term studentship (ICMR-STS) was low among the second semester students (13.9%), but more than half (59.3%) of the students in the eighth semester were aware (difference across semesters, pAwareness about journals, conferences and 'research bodies promoting student research' was low. Students in the senior semesters spent more time on research (6th semester 72.2% and 8th semester 88.9%) than those in the junior semesters (2nd: 66.7% and 4th: 77.8%; difference across semesters, p=0.03). About 3% of students participated in extracurricular research and/or had presented work at a conference. There is a good perception about the need for research but a lack of awareness of the why and how, as well as hardly any practice of ROME among medical students of this medical college.

  3. Nanofabrication of SERS Substrates for Single/Few Molecules Detection

    KAUST Repository

    Melino, Gianluca

    2015-05-04

    Raman spectroscopy is among the most widely employed methods to investigate the properties of materials in several fields of study. Evolution in materials science allowed us to fabricate suitable substrates, at the nanoscale, capable to enhance the electromagnetic field of the signals coming from the samples which at this range turn out to be in most cases singles or a few molecules. This particular variation of the classical technique is called SERS (Surface Enanched Raman Spectroscopy). In this work, the enhancement of the electromagnetic field is obtained by manipulation of the optical properties of metals with respect to their size. By using electroless deposition (bottom up technique), gold and silver nanoparticles were deposited in nanostructured patterns obtained on silicon wafers by means of electron beam lithography (top down technique). Rhodamine 6G in aqueous solution at extremely low concentration (10-8 M) was absorbed on the resultant dimers and the collection of the Raman spectra demonstrated the high efficiency of the substrates.

  4. Synthesis of SERS active Au nanowires in different noncoordinating solvents

    Energy Technology Data Exchange (ETDEWEB)

    Hou Xiaomiao; Zhang Xiaoling, E-mail: zhangxl@bit.edu.cn [Key Laboratory of Cluster Science of Ministry of Education, Beijing Institute of Technology, Department of Chemistry, School of Science (China); Fang Yan, E-mail: fangyan@mail.cnu.edu.cn [Beijing Key Laboratory for Nano-Photonics and Nano-Structure (NPNS), Capital Normal University (China); Chen Shutang; Li Na; Zhou Qi [Key Laboratory of Cluster Science of Ministry of Education, Beijing Institute of Technology, Department of Chemistry, School of Science (China)

    2011-06-15

    Au nanowires with length up to micrometers were synthesized through a simple and one-pot solution growth method. HAuCl{sub 4} was reduced in a micellar structure formed by 1-octadecylamine and oleic acid in hexane, heptane, toluene and chloroform, respectively. As the non-polarity of noncoordinating solvents can affect the nucleation and growth rates of Au nanostructures, Au nanowires with different diameters could be obtained by changing the noncoordinating solvents in the synthetic process. The influences of the solvents on the morphology of Au nanowires were systematically studied. When using hexane as reaction solvent, the product turned to be high portion of Au nanowires with more uniform size than the others. Furthermore, surface-enhanced Raman scattering (SERS) spectrum of 2-thionaphthol was obtained on the Au nanowire-modified substrate, indicating that the as-synthesized Au nanowires have potential for highly sensitive optical detection application.

  5. La persona: razón de ser del derecho

    Directory of Open Access Journals (Sweden)

    Jaime Baquero de la Calle

    2008-01-01

    Full Text Available Todo ordenamiento jurídico se propone alcanzar el bien común. Dentro de este marco institucional, la justicia es el valor supremo que procura garantizar la autoridad competente. ¿Cuándo es posible decir que se está actuando según la justicia? Encontrar una respuesta requiere remontarse a los principios fundamentales que han dado origen a toda formulación jurídica. Y detrás de tales principios se encuentra la persona, destinatario final del ordenamiento. La norma escrita no se funda –por lo menos, no debería ser así– en el azar o las ideas políticas del gobierno de turno. Ante la inminente presencia de una Asamblea Constituyente, es imperativo volver sobre los fundamentos últimos de todo Estado de Derecho.

  6. Laser ablation studies of Deposited Silver Colloids Active in SERS

    International Nuclear Information System (INIS)

    La Porte, R.T.; Moreno, D.S.; Striano, M.C.; Munnoz, M.M.; Garcia-Ramos, J.V.; Cortes, S.S.; Koudoumas, E.

    2002-01-01

    Laser ablation of deposited silver colloids, active in SERS, is carried out at three different laser wavelengths (KrF, XeCl and Nd:YAG at λ = 248, 308 and 532 nm respectively). Emission form excited neutral Ag and Na atoms, present in the ablation plume, is detected with spectral and temporal resolution. The expansion velocity of Ag in the plume is estimated in ∼1x104m s-1, Low-fluence laser ablation of the colloids yields ionized species that are analyzed by time-of-flight mass spectroscopy. Na+ and Agn+(n≤3) are observed. Composition of the mass spectra and widths of the mass peaks are found to be dependent on laser wavelength, suggesting that the dominant ablation mechanisms are different at the different wavelenghts.

  7. Identidades en flujo, diversas maneras de ser colombianos

    Directory of Open Access Journals (Sweden)

    Omar Rincón

    2015-05-01

    Full Text Available La televisión es todo esto porque es lo más común que tenemos entre los colombianos: es un pegante cultural para un país de identidades juntas pero no revueltas. La televisión se ha convertido en el marco de referencia cultural de la mayoría para comprender sus vidas. El maestro Jesús Martín-Barbero en su libro Televisión y melodrama (1992 lo expresa bien cuando escribe que “en medio del desgarramiento que vive el país ¡el fútbol y la telenovela pueden llegar a ser una de las pocas maneras como los colombianos nos sentimos juntos!”. Fútbol, televisión, música y humor son las prácticas más importantes para juntar y conectar a los colombianos.

  8. La razón de ser de los conglomerantes

    Directory of Open Access Journals (Sweden)

    Fernández Paris, J. M.

    1978-09-01

    Full Text Available La palabra cemento sirve para designar cualquier sustancia con capacidad adherente, mientras que el término conglomerante se aplica a la acción de aglutinar en un todo partículas que anteriormente estaban sueltas o independientes. Según su capacidad o no de endurecer bajo agua, los conglomerantes se clasifican en hidráulicos y no hidráulicos. Se denominan hidráulicos a aquéllos que tienen la citada facultad. Entre todos los conglomerantes hidráulicos, han adquirido en la construcción una carta de naturaleza inusitada durante los últimos tiempos los denominados cementos porland. Quiero hacer constar que trato de exponer simplemente aquellos conceptos químicos que, a mi modo de ver y de acuerdo con mi experiencia, constituyen la razón de ser que nos permita apreciar sus cualidades y propiedades.

  9. Ser excepción o del individualismo.

    Directory of Open Access Journals (Sweden)

    Juan Fernando Pérez.

    1998-06-01

    Full Text Available Lección inaugural de la Maestría en Ciencias Sociales: Psicoanálisis, Cultura y Vínculo social. A partir del texto de Freud Los seres excepcionales (también traducido Las excepciones el autor interroga una categoría no psicoanalítica como es la de individualismo, con el concepto de Freud allí expuesto. Propone que el concepto freudiano ser excepción, permite pensar al menos algunas dimensiones de la fenomenología descrita bajo la categoría de individualismo, hecho de interés particular para el examen de algunas modalidades del malestar contemporáneo y de la naturaleza del vínculo social que ese mundo propone. En este orden de ideas aparece cómo las dos figuras que Freud define al lado de “las excepciones”, es decir “los delincuentes por sentimientos de culpa” y “los que fracasan al triunfar”, tienden a desdibujarse en las sociedades de hoy, en favor de una mayor significación esta forma singular de individualismo como es la de “ser excepción”. El hecho revela en forma bien específica cómo el declinamiento de padre en la época de la ciencia implica el fortalecimiento de la tendencia particular del sujeto contemporáneo de definirse como excepción frente a la ley.

  10. Recubrimiento por láser de aleaciones cuasicristalinas

    Directory of Open Access Journals (Sweden)

    Audebert, F.

    1998-04-01

    Full Text Available Quasicrystals are a new class of ordenated structures with metaestable characteristics at room temperature. Quasicrystalline phases can be obtained by rapid quenching from the melt of some alloys. In general, quasicrystals present properties which make these alloys promising for wear and corrosion resistant coatings applications. During the last years, the development of quasicrystalline coatings by means of thermal spray techniques has been impulsed. However, no references have been found of their application by means of laser techniques. In this work four claddings of quasicrystalline compositions formed over aluminum substrate, produced by a continuos CO2 laser using simultaneous powders mixture injection are presented. The claddings were characterized by X ray diffraction, scanning electron microscopy and Vickers microhardness.

    Los cuasicristales constituyen un nuevo tipo de estructuras ordenadas con características metaestables a temperatura ambiente. En general, en determinadas aleaciones, pueden obtenerse por enfriamiento rápido desde el estado líquido. Han demostrado poseer buenas propiedades para su aplicación como recubrimientos resistentes al desgaste y a la corrosión. En este sentido, desde hace unos años, se ha impulsado el desarrollo de su aplicación mediante técnicas de thermal spray, aunque no se han encontrado referencias de su aplicación mediante técnicas de láser. En este trabajo, se presenta la formación de cuatro recubrimientos de aleaciones con composiciones cuasicristalinas sobre un sustrato de aluminio, utilizando un láser continuo de CO2, con inyección simultánea del material en forma de mezcla de polvos. Los mismos fueron caracterizados por difracción de rayos X, microscopía electrónica de barrido y microdureza Vickers.

  11. Integrating Inquiry-Based Science and Education Methods Courses in a "Science Semester" for Future Elementary Teachers

    Science.gov (United States)

    Madsen, J.; Fifield, S.; Allen, D.; Brickhouse, N.; Dagher, Z.; Ford, D.; Shipman, H.

    2001-05-01

    In this NSF-funded project we will adapt problem-based learning (PBL) and other inquiry-based approaches to create an integrated science and education methods curriculum ("science semester") for elementary teacher education majors. Our goal is to foster integrated understandings of science and pedagogy that future elementary teachers need to effectively use inquiry-based approaches in their classrooms. This project responds to calls to improve science education for all students by making preservice teachers' experiences in undergraduate science courses more consistent with reforms at the K-12 level. The involved faculty teach three science courses (biology, earth science, physical science) and an elementary science education methods course that are degree requirements for elementary teacher education majors. Presently, students take the courses in variable sequences and at widely scattered times. Too many students fail to appreciate the value of science courses to their future careers as teachers, and when they reach the methods course in the junior year they often retain little of the science content studied earlier. These episodic encounters with science make it difficult for students to learn the content, and to translate their understandings of science into effective, inquiry-based teaching strategies. To encourage integrated understandings of science concepts and pedagogy we will coordinate the science and methods courses in a junior-year science semester. Traditional subject matter boundaries will be crossed to stress shared themes that teachers must understand to teach standards-based elementary science. We will adapt exemplary approaches that support both learning science and learning how to teach science. Students will work collaboratively on multidisciplinary PBL activities that place science concepts in authentic contexts and build learning skills. "Lecture" meetings will be large group active learning sessions that help students understand difficult

  12. Assessing the Impact of a Semester-Long Course in Agricultural Mechanics on Pre-Service Agricultural Education Teachers' Importance, Confidence, and Knowledge of Welding

    Science.gov (United States)

    Leiby, Brian L.; Robinson, J. Shane; Key, James P.

    2013-01-01

    This study sought to assess the perceptions of Oklahoma pre-service agricultural education teachers regarding the importance of identified welding skills standards and their confidence to teach them, based on a semester-long course on metals and welding. This study also sought to determine pre-service teachers' knowledge of welding prior to and at…

  13. Navigating New Worlds: A Real-Time Look at How Successful and Non-Successful First-Generation College Students Negotiate Their First Semesters

    Science.gov (United States)

    Morales, Erik E.

    2012-01-01

    This study of fifteen first generation American college freshmen documents their initial semester with a focus on factors and dispositions contributing to eventual success or failure. Students were identified prior to campus arrival, allowing for immediate and real-time data collection as they were experiencing the beginning of their college…

  14. Dealing with Complex and Ill-Structured Problems: Results of a Plan-Do-Check-Act Experiment in a Business Engineering Semester

    Science.gov (United States)

    Riis, Jens Ove; Achenbach, Marlies; Israelsen, Poul; Kyvsgaard Hansen, Poul; Johansen, John; Deuse, Jochen

    2017-01-01

    Challenged by increased globalisation and fast technological development, we carried out an experiment in the third semester of a global business engineering programme aimed at identifying conditions for training students in dealing with complex and ill-structured problems of forming a new business. As this includes a fuzzy front end, learning…

  15. Idaho Home Economics. Nutrition and Foods, Apparel and Housing, Parenting and Child Development. Curriculum Guides, Semester Length Courses, Grades 10-12.

    Science.gov (United States)

    Gebo, Emma M., Ed.; And Others

    This curriculum contains three one-semester courses for use in home economics classes in Idaho. The nutrition and foods course is designed to address nutrition and personal life-style. Content emphasis is on food preparation techniques, meal management skills, consumer skills, the impact of nutrition on our lives, and career options in nutrition…

  16. The Effects of Two Semesters of Secondary School Calculus on Students' First and Second Quarter Calculus Grades at the University of Utah

    Science.gov (United States)

    Robinson, William Baker

    1970-01-01

    The predicted and actual achievement in college calculus is compared for students who had studied two semesters of calculus in high school. The regression equation used for prediction was calculated from the performance data of similar students who had not had high school calculus. (CT)

  17. Is there flexibility in the European Semester process? : Exploring interactions between the EU and member states within post-crisis socio-economic governance

    NARCIS (Netherlands)

    Bekker, Sonja

    The consequences of the Eurozone crisis has spurred increased coordination of member state public finances at European level. This also entails the scrutiny of socio-economic issues within the framework of the European semester. However, this process also includes aspects of negotiation in which the

  18. TASK BASED APPROACH IN WRITING ARTICLE (A Field Study: The Seventh Semester Students of PBI 2008 D of STKIP Ponorogo in Academic Year 2011/2012

    Directory of Open Access Journals (Sweden)

    Tintin Susilowati

    2012-06-01

    Full Text Available Abstrak: Menulis adalah salah satu skill dari keterampilan bahasa yang masih menjadi masalah serius  bagi mahasiswa secara umum bahkan bagi mahasiswa semester tujuh jurusan pendidikan bahasa Inggris. Berdasarkan data ditemukan bahwa banyak mahasiswa semester tujuh memiliki keterbatasan pengetahuan tentang struktur paragrap terkait dengan esensi dan proposi dalam penulisan pendahuluan, tubuh dari paragrap untuk mengembangkan ide, serta kesimpulan bahkan mereka juga masih mengalami kesulitan dalam menulis sebuah paragrap. Paragrap seharusnya telah dikuasai oleh mahasiswa semester atas. Sebagai mahasiswa semester tujuh, mereka seharusnya telah mampu untuk menghasilkan tulisan jurnalistik seperti artikel. Penulisan artikel artikel, diterapkan dalam pembelajaran di kelas  menulis. Dalam materi menulis, diuraikan melalui serangkaian kegiatan dari langkah awal sampai produk akhir secara sisematis menggunakan “Task-Based Approach”. Implementasi dari pembelajaran ini menggunakan pendekatan kualitatif. Data diambil dari hasil tulisan mahasiswa dan di analisa menggunakan skala rubrik. Dengan Task-Based Approach, mahasiswa diarahkan untuk mampu menulis artikel. Pembelajaran dilakukan berbasis tugas dengan fokus yang berbeda untuk tiap pertemuan namun tujuan akhirnya mahasiswa mampu menulis artikel secara utuh setelah melakukan  tugas-tugas yang diberikan.

  19. Fostering Distance Training Programme (DTP) Students' Access to Semester Examination Results via SMS at University of Rwanda-College of Education

    Science.gov (United States)

    Nizeyimana, Gerard; Yonah, Zaipuna O.; Nduwingoma, Mathias

    2015-01-01

    This paper presents a situation analysis and implementation of Distance Training Programme (DTP) Semester Examination Results Access (SERA) through Short Message Service (SMS) available anytime and anywhere. "Texting" or SMS mobile phone messaging is rapidly increasing communication in business and community service. The prompting…

  20. A new integrated TLC/MU-ATR/SERS advanced approach for the identification of trace amounts of dyes in mixtures.

    Science.gov (United States)

    Sciutto, Giorgia; Prati, Silvia; Bonacini, Irene; Litti, Lucio; Meneghetti, Moreno; Mazzeo, Rocco

    2017-10-23

    The present research is focused on the setting up of an advanced analytical system for the detection of synthetic dyes. The system is based on the combination of an innovative thin layer chromatography (TLC) plate coupled with enhanced infrared (MU-ATR, metal underlayer attenuated total reflection) and Surface Enhanced Raman (SERS) spectroscopy. In particular, a TLC plate made of silver iodide (AgI) applied onto a gold coated glass slide (AgI@Au) is proposed as an efficient stationary phase for the separation of dyes mixtures. The separated dyes are then identified by means of both enhanced FTIR and SERS, performed directly on the same eluted spots. The use of a mid-IR transparent inorganic salt as stationary phase coupled with the underneath gold layer avoids spectral interferences, enhancing the signal obtained from ATR analyses. At the same time, SERS spectra can be recorded as the TLC plate may act as a SERS active substrate due to the photoreduction of AgI to metallic Ag caused by the exposure to the laser during the Raman analysis. Different mixtures of synthetic dyes of known composition, widely used in dyeing processes, have been tested and the method resulted to be effective in identifying trace amounts in the order of tens nanograms. Moreover, the method has been further evaluated on a real case study represented by dyes extracted from dyed wool. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Study of pyruvate decarboxylase and thiamine kinase from brewer's yeast by SERS

    Science.gov (United States)

    Maskevich, Sergei A.; Chernikevich, Ivan P.; Gachko, Gennedy A.; Kivach, Leonid N.; Strekal, Nataliya D.

    1993-06-01

    The Surface Enhanced Raman Scattering (SERS) spectra of holopyruvate decarboxylase (PDC) and thiamine kinase (ThK) adsorbed on silver electrode were obtained. In contrast to the Raman, the SERS spectrum of PDC contained no modes of tryptophan residues, it indicates a removal of this moiety from the surface. In the SERS spectrum of ThK the bands belonging to ligands bound to the protein were observed. A correlation between the SERS signal intensity and the enzymatic activity of the ThK separate fraction and found. The influence of amino acids on SERS spectra of thiamine (Th) was studied to determine the possible composition on microsurrounding of coenzyme.

  2. SERS substrates fabricated using ceramic filters for the detection of bacteria

    Science.gov (United States)

    Mosier-Boss, P. A.; Sorensen, K. C.; George, R. D.; Obraztsova, A.

    2016-01-01

    SERS substrates were fabricated by filtering either Ag or Au colloidal particles onto rigid, ceramic filters - onto which suspensions of bacteria were then filtered. SERS spectra of the bacteria were obtained using a Raman spectrometer that has an 'orbital raster scan' capability. It was shown that bacteria samples prepared in this manner were uniformly distributed onto the surface of the SERS substrate. The effect of common buffer systems on the SERS spectra was investigated and the utility of using the SERS technique for speciation of bacteria was explored.

  3. Phenomenological features of dreams: Results from dream log studies using the Subjective Experiences Rating Scale (SERS).

    Science.gov (United States)

    Kahan, Tracey L; Claudatos, Stephanie

    2016-04-01

    Self-ratings of dream experiences were obtained from 144 college women for 788 dreams, using the Subjective Experiences Rating Scale (SERS). Consistent with past studies, dreams were characterized by a greater prevalence of vision, audition, and movement than smell, touch, or taste, by both positive and negative emotion, and by a range of cognitive processes. A Principal Components Analysis of SERS ratings revealed ten subscales: four sensory, three affective, one cognitive, and two structural (events/actions, locations). Correlations (Pearson r) among subscale means showed a stronger relationship among the process-oriented features (sensory, cognitive, affective) than between the process-oriented and content-centered (structural) features--a pattern predicted from past research (e.g., Bulkeley & Kahan, 2008). Notably, cognition and positive emotion were associated with a greater number of other phenomenal features than was negative emotion; these findings are consistent with studies of the qualitative features of waking autobiographical memory (e.g., Fredrickson, 2001). Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Performance Characteristics of Bio-Inspired Metal Nanostructures as Surface-Enhanced Raman Scattered (SERS) Substrates.

    Science.gov (United States)

    Areizaga-Martinez, Hector I; Kravchenko, Ivan; Lavrik, Nickolay V; Sepaniak, Michael J; Hernández-Rivera, Samuel P; De Jesús, Marco A

    2016-09-01

    The fabrication of high-performance plasmonic nanomaterials for bio-sensing and trace chemical detection is a field of intense theoretical and experimental research. The use of metal-silicon nanopillar arrays as analytical sensors has been reported with reasonable results in recent years. The use of bio-inspired nanocomposite structures that follow the Fibonacci numerical architecture offers the opportunity to develop nanostructures with theoretically higher and more reproducible plasmonic fields over extended areas. The work presented here describes the nanofabrication process for a series of 40 µm × 40 µm bio-inspired arrays classified as asymmetric fractals (sunflower seeds and romanesco broccoli), bilaterally symmetric (acacia leaves and honeycombs), and radially symmetric (such as orchids and lily flowers) using electron beam lithography. In addition, analytical capabilities were evaluated using surface-enhanced Raman scattering (SERS). The substrate characterization and SERS performance of the developed substrates as the strategies to assess the design performance are presented and discussed. © The Author(s) 2016.

  5. Danmark læser - en kulturkampagne mellem flere tider og mange dagsordner

    DEFF Research Database (Denmark)

    Dalsgård, Anne Line; Lund, Niels D.

    2016-01-01

    The national campaign Denmark is reading (Danmark læser) was carried out in the years 2013-15 and was a significant cultural policy initiative – the biggest of its kind ever in Denmark – with the object of getting more Danes to read fiction. This article describes the aim and contents of the camp......The national campaign Denmark is reading (Danmark læser) was carried out in the years 2013-15 and was a significant cultural policy initiative – the biggest of its kind ever in Denmark – with the object of getting more Danes to read fiction. This article describes the aim and contents...... of the campaign and analyses its position at the interface between established educational thinking and contemporary event culture, as well as considering its relations to other current agendas in the politics of culture and literature: the book market, literacy, public libraries, the concept of dissemination...... into perspective sections of contemporary Scandinavian research about books, literature, reading and the dissemination of literature. The campaign was characterised by its broad social and geographical scope, which both retained Danish public libraries as central players and involved a great number of innovative...

  6. THE VULNERABILITY OF THE BAIA MARE URBAN SYSTEM (ROMANIA TO EXTREME CLIMATE PHENOMENA DURING THE WARM SEMESTER OF THE YEAR

    Directory of Open Access Journals (Sweden)

    DRAGOTĂ CARMEN

    2013-03-01

    Full Text Available The geographical position of the Baia Mare Urban System (intra-hilly depression favours the occurrence of a wide range of extreme climate phenomena which, coupled with the industrial profile of the city (non-ferrous mining and metallurgical industry triggering typical emissions (CO2, SOX, particulate matters and Pb, might pose a significant threat to human health. The article is aiming to assess the occurrence, frequency and amplitude of these extreme climate phenomena based on monthly and daily extreme climatic values from Baia Mare weather station in order to identify the areas more exposed. A GIS-based qualitative-heuristic method was used, each extreme climatic hazard being evaluated on a 1 to 3 scale according to its significance/impact in the study area and assigned with a weight (w and a rank (r, resulting the climate hazard map for the warm semester of the year. The authors further relate the areas exposed to the selected extreme climatic events to socio-economic aspects: demographic and economic in order to delineate the spatial distribution of the environmental vulnerability in the Baia Mare Urban System.

  7. "Ser diferente é normal?"/"Being different: is it normal?"

    Directory of Open Access Journals (Sweden)

    Viviane Veras

    2007-01-01

    Full Text Available A pergunta título deste trabalho retoma o slogan “Ser diferente é normal”, que é parte da campanha criada para uma organização não-governamental que atende portadores de Síndrome de Down. O objetivo é a inclusão social da pessoa com deficiência e o primeiro passo foi propor a inclusão de um grupo de diferentes no grupo dito normal. No vídeo de lançamento da campanha, o diferente, identificado como normal, é mostrado por meio de exemplos – um negro com cabelo black-power, um skin-head, um corpo tatuado, um corpo feminino halterofílico, uma família hippie, uma garota com síndrome de Down. A visão da adolescente dançando reduz, de certo modo, o efeito imaginário que vai além da síndrome, uma vez que apenas o corpo com seus olhinhos puxados se destacam, e não se interrogam questões cognitivas. Minha proposta é refletir sobre o estatuto paradoxal do exemplo, tal como é trabalhado nesse vídeo: se, por definição, um exemplo mostra de fato seu pertencimento a uma classe, pode-se concluir que é exatamente por ser exemplar que ele se encontra fora dela, no exato momento em que a exibe e define. The question in the title of this paper refers to the slogan "ser diferente é normal" ("It´s normal to be different", which is part of a campaign created for a NGO that supports people with Down syndrome. The objective of the campaign is to promote the social inclusion of individuals with Down syndrome, and the first step was to propose the inclusion of a group of "differents" in the so-called normal group. The film launching the campaign shows the different identified as normal by means of examples: a black man exhibiting blackpower haircut, a skin-head, a tattooed body, an over-athletic female body, a hippie family and a girl with Down syndrome. The vision of the dancing teenager lessens the imaginary effect that surpasses the syndrome, since only her body and her little oriental eyes stand out and no cognitive issues are

  8. ¿PERMITE SER FELIZ LA MORAL CRISTIANA?

    Directory of Open Access Journals (Sweden)

    Waldo Romo P

    2006-01-01

    Full Text Available La pregunta que encabeza el artículo ya es desafiante: "¿Permite ser feliz la moral cristiana?". Existe la posibilidad de responder negativamente. El autor, después de analizar algunos pensadores (Nietzsche, entre ellos que han negado a la moral cristiana la posibilidad de hacer feliz al ser humano, presenta las condiciones de posibilidad para que dicha moral se encauce a ser un camino de felicidad. Entre esas condiciones se destaca: el paso de una moral heterónama a una moral de autonomía teónoma, una moral centrada en la persona más que una moral centrada en la ley, una moral de discipulado que pone primero el amor y luego el cumplimiento normativo. Profundiza, al respecto, en el logion de Jesucristo: "El que me ama, cumple mis mandamientos". Esta enseñanza plantea el orden secuencial de toda moral cristiana: porque se ama a Jesús, se entiende el cumplimiento de las normas. Estas se transforman, entonces, en el "test" verificador del amor. De lo contrario, se permanece en un ritualismo normativo, que en defintiva hastía y no lleva a la felicidad. Por ello, el artículo profundiza en una moral de opción fundamental expresada en actitudes y actos morales coherentes con esa opción. Si las condiciones de posibilidad propuestas se llegan a dar, la interrogante que organiza el artículo tendrá una respuesta positivaThe question that heads this article is already challenging: "Does Christian morality permit one to be happy?" The possibility of responding negatively exists. The author, after analyzing the contributions of some thinkers (Nietszche among them who have denied the possibility that Christian morality could make human beings happy, presents the conditions that would orient said morality towards the possibility of becoming a path to happiness. Among those conditions, the author highlights: the passage from a "heteronomous" morality to a morality of "theonomous" autonomy, a morality centered on the person rather than a morality

  9. Research

    African Journals Online (AJOL)

    ebutamanya

    2015-03-02

    Mar 2, 2015 ... Joseph Daniels1,&, Ruth Nduati1,2, James Kiarie1,3, Carey Farquhar1,4,5 .... or basic science research career (Socio-Behavioral Research, .... a research environment that supports knowledge sharing to develop research ...

  10. A Toolkit For CryoSat Investigations By The ESRIN EOP-SER Altimetry Team

    Science.gov (United States)

    Dinardo, Salvatore; Bruno, Lucas; Benveniste, Jerome

    2013-12-01

    The scope of this work is to feature the new tool for the exploitation of the CryoSat data, designed and developed entirely by the Altimetry Team at ESRIN EOP-SER (Earth Observation - Exploitation, Research and Development). The tool framework is composed of two separate components: the first one handles the data collection and management, the second one is the processing toolkit. The CryoSat FBR (Full Bit Rate) data is downlinked uncompressed from the satellite, containing un-averaged individual echoes. This data is made available in the Kiruna CalVal server in a 10 day rolling archive. Daily at ESRIN all the CryoSat FBR data, in SAR and SARin Mode, are downloaded (around 30 Gigabytes) catalogued and archived in local ESRIN EOP-SER workstations. As of March 2013, the total amount of FBR data is over 9 Terabytes, with CryoSat acquisition dates spanning January 2011 to February 2013 (with some gaps). This archive was built by merging partial datasets available at ESTEC and NOAA, that have been kindly made available for EOP-SER team. The on-demand access to this low level data is restricted to expert users with validated ESA P.I. credentials. Currently the main users of the archiving functionality are the team members of the Project CP4O (STSE- CryoSat Plus for Ocean), CNES and NOAA. The second component of the service is the processing toolkit. On the EOP-SER workstations there is internally and independently developed software that is able to process the FBR data in SAR/SARin mode to generate multi-looked echoes (Level 1B) and subsequently able to re-track them in SAR and SARin mode (Level 2) over open ocean, exploiting the SAMOSA model and other internally developed models. The processing segment is used for research & development scopes, supporting the development contracts awarded confronting the deliverables to ESA, on site demonstrations/training to selected users, cross- comparison against third part products (CLS/CNES CPP Products for instance), preparation

  11. Thinking Like Researchers: Action Research and Its Impact on Novice Teachers' Thinking

    Science.gov (United States)

    Davis, Janine; Clayton, Courtney; Broome, John

    2018-01-01

    This project investigated the effects of novice teachers' responses to an action research project conducting during the student-teaching semester. This study drew on a framework that considered the participants' process of research, practice of teaching, and identity as a researcher and utilized a qualitative, multiple case-study approach with an…

  12. A microfluidic dialysis device for complex biological mixture SERS analysis

    KAUST Repository

    Perozziello, Gerardo

    2015-08-01

    In this paper, we present a microfluidic device fabricated with a simple and inexpensive process allowing rapid filtering of peptides from a complex mixture. The polymer microfluidic device can be used for sample preparation in biological applications. The device is fabricated by micromilling and solvent assisted bonding, in which a microdialysis membrane (cut-off of 12-14 kDa) is sandwiched in between an upper and a bottom microfluidic chamber. An external frame connects the microfluidic device to external tubes, microvalves and syringe pumps. Bonding strength and interface sealing are pneumatically tested. Microfluidic protocols are also described by using the presented device to filter a sample composed of specific peptides (MW 1553.73 Da, at a concentration of 1.0 ng/μl) derived from the BRCA1 protein, a tumor-suppressor molecule which plays a pivotal role in the development of breast cancer, and albumin (MW 66.5 kDa, at a concentration of 35 μg/μl), the most represented protein in human plasma. The filtered samples coming out from the microfluidic device were subsequently deposited on a SERS (surface enhanced Raman scattering) substrate for further analysis by Raman spectroscopy. By using this approach, we were able to sort the small peptides from the bigger and highly concentrated protein albumin and to detect them by using a label-free technique at a resolution down to 1.0 ng/μl.

  13. SERS of semiconducting nanoparticles (TIO{sub 2} hybrid composites).

    Energy Technology Data Exchange (ETDEWEB)

    Rajh, T.; Musumeci, A.; Gosztola, D.; Schiller, T.; Dimitrijevic, N. M.; Mujica, V.; Martin, D.; Center for Nanoscale Materials

    2009-05-06

    Raman scattering of molecules adsorbed on the surface of TiO{sub 2} nanoparticles was investigated. We find strong enhancement of Raman scattering in hybrid composites that exhibit charge transfer absorption with TiO{sub 2} nanoparticles. An enhancement factor up to {approx}10{sup 3} was observed in the solutions containing TiO{sub 2} nanoparticles and biomolecules, including the important class of neurotransmitters such as dopamine and dopac (3,4-dihydroxy-phenylacetic acid). Only selected vibrations are enhanced, indicating molecular specificity due to distinct binding and orientation of the biomolecules coupled to the TiO{sub 2} surface. All enhanced modes are associated with the asymmetric vibrations of attached molecules that lower the symmetry of the charge transfer complex. The intensity and the energy of selected vibrations are dependent on the size and shape of nanoparticle support. Moreover, we show that localization of the charge in quantized nanoparticles (2 nm), demonstrated as the blue shift of particle absorption, diminishes SERS enhancement. Importantly, the smallest concentration of adsorbed molecules shows the largest Raman enhancements suggesting the possibility for high sensitivity of this system in the detection of biomolecules that form a charge transfer complex with metal oxide nanoparticles. The wavelength-dependent properties of a hybrid composite suggest a Raman resonant state. Adsorbed molecules that do not show a charge transfer complex show weak enhancements probably due to the dielectric cavity effect.

  14. SERS as a tool for in vitro toxicology.

    Science.gov (United States)

    Fisher, Kate M; McLeish, Jennifer A; Jamieson, Lauren E; Jiang, Jing; Hopgood, James R; McLaughlin, Stephen; Donaldson, Ken; Campbell, Colin J

    2016-06-23

    Measuring markers of stress such as pH and redox potential are important when studying toxicology in in vitro models because they are markers of oxidative stress, apoptosis and viability. While surface enhanced Raman spectroscopy is ideally suited to the measurement of redox potential and pH in live cells, the time-intensive nature and perceived difficulty in signal analysis and interpretation can be a barrier to its broad uptake by the biological community. In this paper we detail the development of signal processing and analysis algorithms that allow SERS spectra to be automatically processed so that the output of the processing is a pH or redox potential value. By automating signal processing we were able to carry out a comparative evaluation of the toxicology of silver and zinc oxide nanoparticles and correlate our findings with qPCR analysis. The combination of these two analytical techniques sheds light on the differences in toxicology between these two materials from the perspective of oxidative stress.

  15. [Eugenics and Falange through the journal Ser (1942-1957)].

    Science.gov (United States)

    Rendon, Sara Navarro

    2016-01-01

    Biopolitics has played an important role in fascist totalitarianism and the-Francoist regime was no exception. From the and with ultimate goal or regulating the population, measures were implemented to increase, care for and indoctrinate the population. This present study analyses the selection and promotion measures of some populations and the marginalisation of others proposed the Spanish Falangist Movement's official publication in the field of medicine, the journal Ser, Revista Medico-Social by the National Delegation of Health of the Traditionalist Spanish Phalanx of the Committees of the National Syndicalist Offensivie (F.E.T y de las J. O. N. S. 1942-1957). In this respect, the analysis of eugenic ideas and practice defended therein become especially interesting, claiming that, through indoctrination and health development, the race would be improved both physically and mentally. From the systematic analysis of the journals's contenets it has been demonstrated that this was one of the instruments used by the dictatorial regime to reconfigure eugenics in accordance with Catholic morals and national syndicalist politics.

  16. Juan O’Gorman. Formas de no ser arquitecto

    Directory of Open Access Journals (Sweden)

    Javier Jerez González

    2015-12-01

    Full Text Available La obra proyectada y construida por Juan O’Gorman a lo largo de su vida traza un recorrido largo y sincopado entre formas de entender la arquitectura totalmente antagónicas. Su primera etapa de radical racionalismo desarrolla, según procedimientos estrictamente técnicos, un lenguaje revolucionario basado en la austeridad y la precisión. A pesar de ello muchas de sus obras destacan por la plasticidad de sus composiciones volumétricas, la riqueza espacial o, incluso, por la creación de atmósferas oníricas. Los primeros años de frenética actividad dan paso a un periodo de voluntario alejamiento de la práctica profesional de la arquitectura: ni una sola obra, ni un solo proyecto durante cerca de 15 años. Tan solo su actividad docente le mantiene en contacto con el mundo de la arquitectura. Cuando Juan O’Gorman vuelve a ejercer como arquitecto, lo hace construyendo algunos de los iconos del movimiento de integración plástica de México: la biblioteca central de la UNAM y su casa en San Jerónimo. A pesar de las enormes diferencias, o más bien oposiciones, entre unos momentos y otros, puede identificarse una invariante clara como señal de identidad personal: una velada voluntad de no ser arquitecto

  17. Fasting mediated increase in p-BAD(ser155) and p-AKT(ser473) in the prefrontal cortex of mice.

    Science.gov (United States)

    Pitchaimani, Vigneshwaran; Arumugam, Somasundaram; Thandavarayan, Rajarajan Amirthalingam; Karuppagounder, Vengadeshprabhu; Sreedhar, Remya; Afrin, Rejina; Harima, Meilei; Suzuki, Hiroshi; Miyashita, Shizuka; Nomoto, Mayumi; Sone, Hirohito; Suzuki, Kenji; Watanabe, Kenichi

    2014-09-05

    BAD-deficient mice and fasting have several common functional roles in seizures, beta-hydroxybutyrate (BHB) uptake in brain and alteration in counterregulatory hormonal regulation during hypoglycemia. Neuronal specific insulin receptor knockout (NIRKO) mice display impaired counterregulatory hormonal responses during hypoglycemia. In this study we investigated the fasting mediated expression of p-BAD(ser155) and p-AKT(ser473) in different regions of brain (prefrontal cortex, hippocampus, midbrain and hypothalamus). Fasting specifically increases p-BAD(ser155) and p-AKT(ser473) in prefrontal cortex and decreases in other regions of brain. Our results suggest that fasting may increase the uptake BHB by decreasing p-BAD(ser155) in the brain during hypoglycemia except prefrontal cortex and it uncovers specific functional area of p-BAD(ser155) and p-AKT(ser473) that may regulates counter regulatory hormonal response. Overall in support with previous findings, fasting mediated hypoglycemia activates prefrontal cortex insulin signaling which influences the hypothalamic paraventricular nucleus mediated activation of sympathoadrenal hormonal responses. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. Sonochemically synthesized Ag nanoparticles as a SERS active substrate and effect of surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Dar, Nitzan, E-mail: n58987012@mail.ncku.edu.tw [Department of Material Science and Engineering, National Cheng Kung University, Tainan 70101 Taiwan (China); Chen, Kuang-Yu [Department of Material Science and Engineering, National Cheng Kung University, Tainan 70101 Taiwan (China); Nien, Yung-Tang, E-mail: ytnien@nfu.edu.tw [Department of Materials Science and Engineering, National Formosa University, Huwei, Yunlin 63201, Taiwan (China); Perkas, Nina [Institute of nanotechnology and advanced materials, Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002 (Israel); Gedanken, Aharon, E-mail: Aharon.Gedanken@biu.ac.il [Institute of nanotechnology and advanced materials, Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002 (Israel); Chen, In-Gann, E-mail: ingann@mail.ncku.edu.tw [Department of Material Science and Engineering, National Cheng Kung University, Tainan 70101 Taiwan (China)

    2015-03-15

    Highlights: • Solid state Ag SERS active substrates were sonochemically synthesized. • High intensity SERS spectra of both crystal violet and rhodamine 6G were observed. • We discovered that PVP aided synthesized substrates showed higher SERS intensity. - Abstract: Surface enhanced Raman scattering (SERS) enables the detection of substances at low concentrations using silver or gold nanostructure. The SERS technique has many applications, such as environmental detection and biosensing. Sonochemistry is an excellent and cheap deposition technique for coating substrates in a form of nanostructure at ambient temperature. It can also be utilized to prepare large SERS substrates. Here, we used the advantages of sonochemistry to deposit solid SERS substrates immobilized on GaN nanostructure. Morphology was studied by scanning electron microscopy. The elemental composition and the spatial distribution were examined by energy dispersive X-ray spectroscopy. The crystal structure and atomic presence was confirmed by X-ray diffraction. SERS substrates were examined with the analytes crystal violet (10{sup −5} M) and rhodamine 6G (10{sup −6} M), they showed prominent characteristic peaks. We discovered that the SERS intensity of poly-vinyl-pyrrolidinone aided sonochemical deposition of Ag nanoparticles was increased. The reason for the effect is morphological changes of the Ag nanoparticles. Smaller nanoparticles were fabricated, which increase their SERS intensity.

  19. Research

    African Journals Online (AJOL)

    A descriptive qualitative research design was used to determine whether participants ... simulation as a teaching method; a manikin offering effective learning; confidence ..... Tesch R. Qualitative Research: Analysis Types and Software Tools.

  20. Research oriented projects on design themese

    DEFF Research Database (Denmark)

    Tollestrup, Christian; Eriksen, Kaare; Ovesen, Nis

    2011-01-01

    How can design students do research-oriented projects about design themes? At the 3rd semester at the Industrial Design Master Program at Aalborg University this is done by taking research oriented learning objectives on design theories and methods and combining them with experimental case studie...... and professional self-reflection amongst students are improved....

  1. Optimizing How We Teach Research Methods

    Science.gov (United States)

    Cvancara, Kristen E.

    2017-01-01

    Courses: Research Methods (undergraduate or graduate level). Objective: The aim of this exercise is to optimize the ability for students to integrate an understanding of various methodologies across research paradigms within a 15-week semester, including a review of procedural steps and experiential learning activities to practice each method, a…

  2. Research

    African Journals Online (AJOL)

    research process, as part of which students must find and appraise evidence from research.[5] This highlights that teaching research methodology is inclined towards equipping students ... Students believed that evidence-based practice was vital, yet their understanding of the concept was restricted when compared with the.

  3. The IkappaB kinase family phosphorylates the Parkinson's disease kinase LRRK2 at Ser935 and Ser910 during Toll-like receptor signaling.

    Directory of Open Access Journals (Sweden)

    Nicolas Dzamko

    Full Text Available Mutations in leucine-rich repeat kinase 2 (LRRK2 are strongly associated with late-onset autosomal dominant Parkinson's disease. LRRK2 is highly expressed in immune cells and recent work points towards a link between LRRK2 and innate immunity. Here we demonstrate that stimulation of the Toll-Like Receptor (TLR pathway by MyD88-dependent agonists in bone marrow-derived macrophages (BMDMs or RAW264.7 macrophages induces marked phosphorylation of LRRK2 at Ser910 and Ser935, the phosphorylation sites that regulate the binding of 14-3-3 to LRRK2. Phosphorylation of these residues is prevented by knock-out of MyD88 in BMDMs, but not the alternative TLR adaptor protein TRIF. Utilising both pharmacological inhibitors, including a new TAK1 inhibitor, NG25, and genetic models, we provide evidence that both the canonical (IKKα and IKKβ and IKK-related (IKKε and TBK1 kinases mediate TLR agonist induced phosphorylation of LRRK2 in vivo. Moreover, all four IKK members directly phosphorylate LRRK2 at Ser910 and Ser935 in vitro. Consistent with previous work describing Ser910 and Ser935 as pharmacodynamic biomarkers of LRRK2 activity, we find that the TLR independent basal phosphorylation of LRRK2 at Ser910 and Ser935 is abolished following treatment of macrophages with LRRK2 kinase inhibitors. However, the increased phosphorylation of Ser910 and Ser935 induced by activation of the MyD88 pathway is insensitive to LRRK2 kinase inhibitors. Finally, employing LRRK2-deficient BMDMs, we present data indicating that LRRK2 does not play a major role in regulating the secretion of inflammatory cytokines induced by activation of the MyD88 pathway. Our findings provide the first direct link between LRRK2 and the IKKs that mediate many immune responses. Further work is required to uncover the physiological roles that phosphorylation of LRRK2 by IKKs play in controlling macrophage biology and to determine how phosphorylation of LRRK2 by IKKs impacts upon the use of Ser

  4. ACCOUNTABILITY: A RAZÃO DE SER DA CONTABILIDADE

    Directory of Open Access Journals (Sweden)

    MASAYUKI NAKAGAWA, MIBA

    2007-12-01

    Full Text Available Este trabalho teve como objetivo compreender se a accountability é, ou não, a razão de ser da Contabilidade. Se a resposta for positiva e corretamente compreendida pelos professores, pesquisadores e profissionais da Contabilidade, poderemos alimentar a esperança de que o nosso status social, político e econômica atingirá brevemente o nível desejado por todos nós, na mesma medida em que o conceito de accountability for aplicado em nosso País, com due diligence. As pesquisas que vêm sendo realizadas há mais de 15 (quinze anos na Fundação Instituto de Pesquisas Contábeis, Atuariais e Financeiras (Fipecafi vinculada à FEA/USP, revelam que, no mundo dos negócios públicos e privados, existem basicamente duas formas de accountability, uma delas é de natureza exógena e outra endógena. As duas formas de accountability contribuem para a compreensão do conceito de plena accountability a que se refere o modelo de governança empresarial da International Federation of Accountants (Ifac. A pesquisa de campo que, no início dos anos 90, foi objeto de uma consulta da diretoria para a América do Sul e Caribe do Banco Mundial à Fipecafi, com o objetivo de se mensurar o nível de accountability no Brasil, tanto no setor público como privado, é algo que ainda permanece em aberto, como desafio para os futuros pesquisadores desse tema.

  5. ACCOUNTABILITY: A RAZÃO DE SER DA CONTABILIDADE

    Directory of Open Access Journals (Sweden)

    MIBA MASAYUKI NAKAGAWA

    2007-01-01

    Full Text Available Este trabajo tuvo como objetivo comprender si la accountability es, o no, la razón de ser de la Contabilidad. Si la respuesta es positiva y correctamente comprendida por los maestros, investigadores y profesionales de la Contabilidad, podremos alimentar la esperanza de que nuestro estatus social, político y económica alcanzará brevemente el nivel deseado por todos nosotros, en la misma medida en la que el concepto de accountability sea aplicado en nuestro País, con due diligence. Las pesquisas que vienen siendo realizadas hace más de 15 (quince años en la Fundación Instituto de Investigaciones Contables, Actuarias y Financieras (Fipecafi vinculada a la FEA/USP, revelan que, en el mundo de los negocios públicos y privados, existen básicamente dos formas de accountability, de ellas es de naturaleza exógena y otra endógena. Las dos formas de accountability aportan para la comprensión del concepto de plena accountability a que se refiere el modelo de gobierno empresarial de la International Federation of Accountants (Ifac. La pesquisa de campo que, en el inicio de los años 90, fue objeto de una consulta de la directoria para América del Sur y Caribe del Banco Mundial a la Fipecafi, con el objetivo de medirse el nivel de accountability en Brasil, tanto en el sector público como privado, es algo que aún permanece en abierto, como desafío para los porvenires encuestadores de esa tema.

  6. Surface-enhanced Raman spectroscopy (SERS) using Ag nanoparticle films produced by pulsed laser deposition

    Energy Technology Data Exchange (ETDEWEB)

    Smyth, C.A., E-mail: smythc2@tcd.ie [School of Physics, Trinity College Dublin, Dublin 2 (Ireland); Mirza, I.; Lunney, J.G.; McCabe, E.M. [School of Physics, Trinity College Dublin, Dublin 2 (Ireland)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer Pulsed laser deposition (PLD) produces silver nanoparticle films. Black-Right-Pointing-Pointer These films can be used for surface-enhanced Raman spectroscopy (SERS). Black-Right-Pointing-Pointer Commercial film shows good SERS reproducibility but poor signal intensity. Black-Right-Pointing-Pointer PLD shows a good SERS response coupled with good reproducibility. - Abstract: Thin silver nanoparticle films, of thickness 7 nm, were deposited onto glass microslides using pulsed laser deposition (PLD). The films were then characterised using UV-vis spectroscopy and scanning transmission electron microscopy before Rhodamine 6G was deposited onto them for investigation using surface-enhanced Raman spectroscopy (SERS). The sensitivity obtained using SERS was compared to that obtained using a colloidal silver suspension and also to a commercial SERS substrate. The reproducibility of the films is also examined using statistical analysis.

  7. Improving SERS Detection of Bacillus thuringiensis Using Silver Nanoparticles Reduced with Hydroxylamine and with Citrate Capped Borohydride

    International Nuclear Information System (INIS)

    Felix-Rivera, H.; Gonzalez, R.; Rodriguez, G.D.M.; Oliva, M. P.; Hernandez-Rivera, S.P.; Rios-Velazquez, C.

    2011-01-01

    The development of techniques that could be useful in fields other than biological warfare agents countermeasures such as medical diagnostics, industrial microbiology, and environmental applications have become a very important subject of research. Raman spectroscopy can be used in near field or at long distances from the sample to obtain fingerprinting information of chemical composition of microorganisms. In this research, biochemical components of the cell wall and endospores of Bacillus thuringiensis (Bt) were identified by surface-enhanced Raman scattering (SERS) spectroscopy using silver (Ag) nanoparticles (NPs) reduced by hydroxylamine and borohydride capped with sodium citrate. Activation of hot spots, aggregation and surface charge modification of the NPs, was studied and optimized to obtain signal enhancements from Bt by SERS. Slight aggregation of the NPs as well as surface charge modification to a more acidic ambient was induced using small-size borohydride-reduced NPs in the form of metallic suspensions aimed at increasing the Ag NP-Bt interactions. Hydroxylamine-reduced NPs required slight aggregation and no pH modifications in order to obtain high spectral quality results in bringing out SERS signatures of Bt.

  8. Improving SERS Detection of Bacillus thuringiensis Using Silver Nanoparticles Reduced with Hydroxylamine and with Citrate Capped Borohydride

    Directory of Open Access Journals (Sweden)

    Hilsamar Félix-Rivera

    2011-01-01

    Full Text Available The development of techniques that could be useful in fields other than biological warfare agents countermeasures such as medical diagnostics, industrial microbiology, and environmental applications have become a very important subject of research. Raman spectroscopy can be used in near field or at long distances from the sample to obtain fingerprinting information of chemical composition of microorganisms. In this research, biochemical components of the cell wall and endospores of Bacillus thuringiensis (Bt were identified by surface-enhanced Raman scattering (SERS spectroscopy using silver (Ag nanoparticles (NPs reduced by hydroxylamine and borohydride capped with sodium citrate. Activation of “hot spots”, aggregation and surface charge modification of the NPs, was studied and optimized to obtain signal enhancements from Bt by SERS. Slight aggregation of the NPs as well as surface charge modification to a more acidic ambient was induced using small-size borohydride-reduced NPs in the form of metallic suspensions aimed at increasing the Ag NP-Bt interactions. Hydroxylamine-reduced NPs required slight aggregation and no pH modifications in order to obtain high spectral quality results in bringing out SERS signatures of Bt.

  9. Fabrication of Chitosan-gold Nanocomposites Combined with Optical Fiber as SERS Substrates to Detect Dopamine Molecules

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jaewook; Kang, Ikjoong [Gachon Univ., Seongnam (Korea, Republic of)

    2014-01-15

    This research was aimed to fabricate an optical fiber-based SERS substrate which can detect dopamine neurotransmitters. Chitosan nanoparticles (NPs) were firstly anchored on the surface of optical fiber, and then gold layer was subseque N{sub T}ly deposited on the anchored chitosan NPs via electroless plating method. Finally, chitosan-gold nanocomposites combined with optical fiber reacted with dopamine molecules of 100-1500 mg/ day which is a standard daily dose for Parkinson's disease patientss. The amplified Raman signal at 1348 cm{sup -1} obtained from optical fiber-based SERS substrate was plotted versus dopamine concentrations (1-10 mM), demonstrating an approximate linearity of Y = 303.03X + 2385.8 (R{sup 2} = 0.97) with narrow margin errors. The optical fiber-based Raman system can be potentially applicable to in-vitro (or in-vivo) detection of probe molecules.

  10. Self-assembly Ag nanoparticle monolayer film as SERS Substrate for pesticide detection

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Li, E-mail: zhlisuzh@163.com [School of Chemistry and Life Science, Anhui Key Laboratory of Spin Electron and Nanomaterials (Cultivating Base), Suzhou University, SuZhou 234000 (China)

    2013-04-01

    A self-assembled protocol is introduced to provide effective platforms for the fabrication of ordered Ag nanosized monolayer film. The assembled Ag nanosized monolayer film was characterized using scanning electronic microscopy and surface-enhanced Raman scattering (SERS). The results show that the assembled SERS substrate own excellent Raman enhancement and reproducibility. The synthesized SERS-active substrate was further used to detect methyl-parathion, and the limitation of detection can reach 10{sup −7} M.

  11. El ser humano y sus posibilidades de construcción desde el cuidado

    Directory of Open Access Journals (Sweden)

    Alacoque Lorenzini Erdmann

    2003-01-01

    Full Text Available El artículo presenta algunas concepciones del ser humano en relación con el cuidado de enfermería. A partir de la organización de la vida se establecen relaciones, interacciones del ser humano, sus límites y posibilidades para el cuidado con la vida, con lo cotidiano y con la naturaleza. Resalta la importancia y el compromiso en la construcción colectiva del ser ciudadano.

  12. Las segundas partes sí pueden ser mejores: algunas reflexiones sobre el uso de datos secundarios en la investigación cualitativa The second parts may be better: some reflections on the use of secondary data in qualitative research

    Directory of Open Access Journals (Sweden)

    Adrián Scribano

    2009-12-01

    Full Text Available El análisis de datos secundarios es una de las estrategias más "antiguas" que los sociólogos han empleado para dar cuenta de fenómenos de la realidad social sobre los que se disponía de información elaborada por otros El presente trabajo tiene por objetivo establecer una reflexión sistemática sobre el uso de información secundaria en los procesos de investigación social cualitativos. El articulo consta de cuatro partes: 1.- hacia una definición de dato y análisis secundario; 2. ventajas y desventajas del uso de información secundaria; 3.- cómo, por qué y para qué re-usar información cualitativa, y 4.- algunas propuestas a modo de apertura de un campo de discusión. Abogamos por establecer criterios claros que puedan facilitar el uso y análisis de información elaborada por otros y/o en diferentes contextos de producción.The analysis of secondary data is one of the "oldest" strategies that sociologists have used to work with the phenomena of social reality when the available information was prepared by others. This study intends to establish a systematic reflection on the use of secondary information in the processes of qualitative social research. The article is divided into four parts: the first works on a definition of data and secondary analysis; the second part discusses advantages and disadvantages of the use of qualitative information; the third asks how, why and what for is the reuse of qualitative information; and finally the fourth part presents some proposals for discussion. The aim is to establish clear criteria that would facilitate the use and analysis of information produced by others and/or in different contexts of production.

  13. Improving SERS uniformity by isolating hot spots in gold rod-in-shell nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shanshan; Liu, Zhonghui [Shanghai Jiao Tong University, School of Biomedical Engineering & Med-X Research Institute (China); Bartic, Carmen [KU Leuven, Department of Physics (Belgium); Xu, Hong, E-mail: xuhong@sjtu.edu.cn; Ye, Jian, E-mail: yejian78@sjtu.edu.cn [Shanghai Jiao Tong University, School of Biomedical Engineering & Med-X Research Institute (China)

    2016-08-15

    Surface-enhanced Raman scattering (SERS) tags show ultrasensitivity and multiplexing abilities due to strong and characteristic Raman signals and therefore can be utilized as optical labeling agents similar to fluorescent dyes and quantum dots for biosensing and bioimaging. However, SERS tags have the difficulty to realize quantitative analysis due to the uniformity and reproducibility issue. In this work, we have reported on a new type of SERS tag called Au rod-in-shell (RIS) gap-enhanced Raman tag (GERT). With the high-resolution transmission electron microscopy (TEM) and optical absorbance measurements, we have demonstrated the subnanometer sized gap junctions inside the RIS GERTs. SERS measurements and FDTD calculations show that the core–shell subnanometer gap geometry in the RIS GERTs not only generates strong SERS hot spots but also isolates SERS hot spots by Au shells to avoid the influence when the particle aggregates form, therefore showing better SERS uniformity and stronger SERS intensity than normal Au nanorods. Those RIS NPs exhibit great potential as the labeling agents for SERS-based bioimaging and biosensing applications.

  14. Surface-enhanced Raman scattering (SERS) for detection of phenylketonuria for newborn screening

    Science.gov (United States)

    Javanmard, M.; Davis, R. W.

    2014-02-01

    Diagnosis of Phenylketonuria (PKU) in newborns is important because it can potentially help prevent mental retardation since it is treatable by dietary means. PKU results in phenylketonurics having phenylalanine levels as high as 2 mM whereas the normal upper limit in healthy newborns is 120 uM. To this end, we are developing a microfluidic platform integrated with a SERS substrate for detection of high levels of phenylalanine. We have successfully demonstrated SERS detection of phenylalanine using various SERS substrates fabricated using nanosphere lithography, which exhibit high levels of field enhancement. We show detection of SERS at clinically relevant levels.

  15. Improving SERS uniformity by isolating hot spots in gold rod-in-shell nanoparticles

    International Nuclear Information System (INIS)

    Wang, Shanshan; Liu, Zhonghui; Bartic, Carmen; Xu, Hong; Ye, Jian

    2016-01-01

    Surface-enhanced Raman scattering (SERS) tags show ultrasensitivity and multiplexing abilities due to strong and characteristic Raman signals and therefore can be utilized as optical labeling agents similar to fluorescent dyes and quantum dots for biosensing and bioimaging. However, SERS tags have the difficulty to realize quantitative analysis due to the uniformity and reproducibility issue. In this work, we have reported on a new type of SERS tag called Au rod-in-shell (RIS) gap-enhanced Raman tag (GERT). With the high-resolution transmission electron microscopy (TEM) and optical absorbance measurements, we have demonstrated the subnanometer sized gap junctions inside the RIS GERTs. SERS measurements and FDTD calculations show that the core–shell subnanometer gap geometry in the RIS GERTs not only generates strong SERS hot spots but also isolates SERS hot spots by Au shells to avoid the influence when the particle aggregates form, therefore showing better SERS uniformity and stronger SERS intensity than normal Au nanorods. Those RIS NPs exhibit great potential as the labeling agents for SERS-based bioimaging and biosensing applications.

  16. TLC-SERS Plates with a Built-In SERS Layer Consisting of Cap-Shaped Noble Metal Nanoparticles Intended for Environmental Monitoring and Food Safety Assurance

    Directory of Open Access Journals (Sweden)

    H. Takei

    2015-01-01

    Full Text Available We report on a thin layer chromatograph (TLC with a built-in surface enhanced Raman scattering (SERS layer for in-situ identification of chemical species separated by TLC. Our goal is to monitor mixture samples or diluted target molecules suspended in a host material, as happens often in environmental monitoring or detection of food additives. We demonstrate that the TLC-SERS can separate mixture samples and provide in-situ SERS spectra. One sample investigated was a mixture consisting of equal portions of Raman-active chemical species, rhodamine 6 G (R6G, crystal violet (CV, and 1,2-di(4-pyridylethylene (BPE. The three components could be separated and their SERS spectra were obtained from different locations. Another sample was skim milk with a trace amount of melamine. Without development, no characteristic peaks were observed, but after development, a peak was observed at 694 cm−1. Unlike previous TLC-SERS whereby noble metal nanoparticles are added after development of a sample, having a built-in SERS layer greatly facilitates analysis as well as maintaining high uniformity of noble metal nanoparticles.

  17. Research

    African Journals Online (AJOL)

    2014-05-06

    May 6, 2014 ... facilitate and support articulation between the ECT mid-level worker qualification and the professional B EMC degree. Methods. The researchers used an exploratory, sequential mixed-method design, which is characterised by a qualitative phase of research followed by a quantitative phase. This design is ...

  18. Research

    African Journals Online (AJOL)

    supports medical education and research at institutions in 12 ... (CBE). CapacityPlus, led by IntraHealth International, is the USAID-funded ... acquire public health, clinical, and/or research skills, usually through applied learning in a .... If students were evaluated, indicate the type of student (i.e. medical, dental, nursing, etc.) ...

  19. Research

    African Journals Online (AJOL)

    abp

    2017-01-24

    Jan 24, 2017 ... and the specific rotavirus VP4 (P-types) and VP7 (G-types) determined. Results: The .... Centre for Virus Research (CVR) of the Kenya Medical Research. Institute (KEMRI) ... rotavirus dsRNA was run on 10% polyacrylamide resolving gels using a large format .... What is known about this topic. •. Rotavirus is ...

  20. Monomer functionalized silica coated with Ag nanoparticles for enhanced SERS hotspots

    Science.gov (United States)

    Newmai, M. Boazbou; Verma, Manoj; Kumar, P. Senthil

    2018-05-01

    Mesoporous silica (SiO2) spheres are well-known for their excellent chromatographic properties such as the relatively high specific surface, large pore volume, uniform particle size, narrow pore size distribution with favorable pore connectivity; whereas the noble metal Ag nanoparticles have unique size/shape dependant surface plasmon resonance with wide ranging applications. Thus, the desire to synchronize both their properties for specific applications has naturally prompted research in the design and synthesis of core-shell type novel nanoAg@mesoSiO2 nanocomposites, which display potential utility in applications such as photothermal therapy, photocatalysis, molecular sensing, and photovoltaics. In the present work, SiO2 spheres were carefully functionalized with the monomer, N-vinyl pyrrolidone (NVP), which cohesively controls the uniform mass transfer of Ag+ metal ions, thereby enabling its sequential reduction to zerovalent Ag (in the presence of slightly excess NaOH) by electron transfer from nucleophilic attack of the NVP vinyl group by the water molecules even under ambient conditions. Complete metal nanoshell coverage of the silica surface was obtained after multiple Ag deposition cycles, as systematically confirmed from the BET, TEM, optical and FTIR characterization. Our present Ag-coated silica spheres were directly utilized as viable SERS substrates with high sensitivity in contrast with other long chain polymer/surfactant coated silica spheres, owing to the presence of significant number of nanogaps enhanced SERS 'hotspots', which were methodically analyzed utilizing two example analytes, such as crystal violet (CV) and calendula officinalis (CaF).

  1. The role of self-regulated learning in explaining examination performance of college students in first-semester general chemistry

    Science.gov (United States)

    Beckley, Scott

    Many college students struggle with first-semester general chemistry. Prior studies have shown that a student's prior knowledge of chemistry, a cognitive factor, does not account for the total variance when measured by examination scores. This study explored the role of self-regulated learning (SRL) to identify the degree of success or failure of students with two outcome variables (i.e., American Chemical Society Comprehensive First-Term General Chemistry Examination (Form 2009) and hour-examination averages). The SRL construct consists of three interrelated components (i.e., cognitive, metacognitive, and motivational). SRL theory focuses on the idea of reciprocal determinism, in which the impact of one component of self-regulation affects the other two components. In the quantitative portion of this mixed methods study, eight measures of SRL were used to determine the `level' of self-regulation for each student. SRL variables were used in regression analysis and provided additional and unique variances. Cluster analysis techniques identified two distinct groups of students (i.e., adaptive and maladaptive). Generally, adaptive learners were associated with higher levels of SRL and success in the course; maladaptive learners had lower levels of SRL and struggled with the course demands. For the qualitative portion of the study, student volunteers (n = 8) were interviewed to gauge their views on the role of instruction in influencing their examination performances. The findings indicated that perceptions of teaching methods, demands of the course, course structure, feedback, and assessments were associated with the students' levels of self-regulation. Interviews revealed four SRL styles. Rote memorizers tended to fragment instruction and then memorize each fragment, while algorithmic memorizers tended to imitate the step-by-step problem-solving strategies of the instructor or the textbook. Globalizers were intrinsically motivated to learn the material but tended to

  2. Applying cheerful disco learning for improving of motivation and learning result of PKn in grade viii c students junior high school 1 Kebumen in second semester 2013/2014 academic years

    Directory of Open Access Journals (Sweden)

    Siti Makmuroh

    2017-06-01

    Full Text Available The aim of this classroom action research is to improve students’ learning motivation, learning result of PKn on Basic Competence of Describing Indonesian Government System and the Roles of the State Institutions as the Sovereignty Executive and the characters of Grade VIII C Students of Junior High School 1 of Kebumen in Second Semester of Academic Year 2013/2014 by applying CHEERFUL DISCO learning method. The research is a classroom action research conducted in two cycles; each cycle of which includes planning, conducting, observation, and reflection. The result of the research shows that the learning method was able to improve the students’ learning motivation in learning activities from 62.37% in pre cycle to 73.74% in the first cycle, then from 78.91% in the second cycle, improved the PKn learning achievement in mastering concept of the ability to describe Indonesian Government System and the Roles of the State Institutions as the Sovereignty Executive, which can be seen that the students’ achievement test result is improving in average from 78.18 with 54.55% of mastery learning in pre cycle to 83.23 with 72.73% of mastery learning in the first cycle, then it was improved to 86.59 in average with 81.82% of mastery learning in the second cycle.

  3. Research

    African Journals Online (AJOL)

    abp

    2017-10-25

    Oct 25, 2017 ... stigma and superstition are known to lead to frequent presentation .... The limited documented research on challenges to help-seeking behaviour for cancer ..... to touch your breast [16] that breast self-examination may cause.

  4. Research

    African Journals Online (AJOL)

    ebutamanya

    2015-10-02

    Oct 2, 2015 ... thought to prevent infection, but recent research has proven otherwise. In addition ... One patient had ophthalmalgia and was exposed to. Kaiy for one year and ... migraine, ear infections, tuberculosis, bone fractures, epilepsy,.

  5. Research

    African Journals Online (AJOL)

    abp

    2016-07-12

    Jul 12, 2016 ... multiple risk factors provides support for multiple-behavior interventions as ... consumption) with smoking therefore needs further research. As such this study .... restaurants, in bars, and on a statewide basis. They preferred to.

  6. Research

    African Journals Online (AJOL)

    The mini-clinical-evaluation exercise (mini-CEX) is a way of assessing the clinical ... Ethical approval for this study was obtained from the Medical Health. Research ..... mini-CEX assessment and feedback session, the greater the likelihood of.

  7. Research

    African Journals Online (AJOL)

    abp

    2016-04-14

    Apr 14, 2016 ... Qualitative data, content analysis approach was used. Results: Overall 422 .... Study design: A mixed method cross-sectional design using both quantitative and qualitative research methods as described by. Hanson et al [33] ...

  8. Research

    International Nuclear Information System (INIS)

    1999-01-01

    Subjects covered in this section are: (1) PCAST panel promotes energy research cooperation; (2) Letter issued by ANS urges funding balance in FFTF restart consideration and (3) FESAC panel releases report on priorities and balance

  9. Research

    African Journals Online (AJOL)

    Research. December 2017, Vol. 9, No. 4 AJHPE 171. During curriculum development, teachers ... Ideally, examiners need an educational method to determine ..... A major focus of this study was addressing the human resource gap when.

  10. El deber ser de la auditoría

    Directory of Open Access Journals (Sweden)

    Omar de Jesús Montilla Galvis

    2006-01-01

    Full Text Available No falta mucho tiempo para asistir a la integración de las sociedades de la Tierra, a llegar a lo que algunos denominan “aldea global”. No podemos detener los cambios, u oponernos a ellos con la idea de que si les somos indiferentes y no les damos importancia no suceden. Las naciones se vienen transformando multidimensionalmente, no es sólo la tecnología, ni los nichos de mercado, nilas formas de producción, ni la competencia en las economías liberadas, es uncambio en la manera cognoscitiva de pensar y actuar en el mundo de hoy. La auditoría es una práctica de trascendental importancia social y económica, permite entablar relaciones de diversa índole entre los agentes económicos, debido a la confianza que se deposita en el trabajo de los contadores públicos cuando ellos extienden su garantía personal o fe pública, respecto del trabajo de investigación denominado auditoría. Es respecto al conocimiento sobre la auditoría que el presente artículo propone hacerle frente a la necesidad de cambio, las adaptaciones y transformaciones con las que sobreviven las especies, la auditoría se ve en grave riesgo de ser absorbida por otras profesiones, motivo por el cual es necesario comenzar un proceso de adaptación para que sobreviva como una práctica propia de los contadores públicos. La adaptación propuesta tiene como finla evolución de la auditoría, “articulando” toda la información derivada del desarrollo del objeto social de las organizaciones para realizar gestión del conocimiento en las mismas, de este modo convertir dicho conocimiento en la ventaja competitiva más importante de la organización. No es posible esperar que la auditoría continúe con las ideas de su génesis antes de la era cristiana, o con los cambios sufridos a causa de la gran depresión, la responsabilidad de la auditoría ahora tiene que ver con el mejoramiento dela sociedad como efecto del cambio de las organizaciones. Es hora de romper el statu quo

  11. A Ag synchronously deposited and doped TiO2 hybrid as an ultrasensitive SERS substrate: a multifunctional platform for SERS detection and photocatalytic degradation.

    Science.gov (United States)

    Yang, Libin; Sang, Qinqin; Du, Juan; Yang, Ming; Li, Xiuling; Shen, Yu; Han, Xiaoxia; Jiang, Xin; Zhao, Bing

    2018-06-06

    Ag simultaneously deposited and doped TiO2 (Ag-TiO2) hybrid nanoparticles (NPs) were prepared via a sol-hydrothermal method, as both a sensitive surface-enhanced Raman scattering (SERS) substrate and a superior photocatalyst for the first time. Ag-TiO2 hybrid NPs exhibit excellent SERS performance for several probe molecules and the enhancement factor is calculated to be 1.86 × 105. The detection limit of the 4-mercaptobenzoic acid (4-MBA) probe on the Ag-TiO2 substrate is 1 × 10-9 mol L-1, which is four orders of magnitude lower than that on pure TiO2 as a consequence of the synergistic effects of TiO2 and Ag. This is the highest SERS sensitivity among the reported semiconductor substrates and even comparable to noble metal substrates, and a SERS enhancement mechanism from the synergistic contribution of the semiconductor and noble metal was proposed. And importantly, the Ag-TiO2 hybrid shows excellent photocatalytic degradation activity for the detected species under UV light irradiation at lower concentration conditions, even for the hard to degrade 4-MBA molecule. This makes the Ag-TiO2 hybrid promising as a dual-function platform for both highly sensitive SERS detection and photocatalytic degradation of a pollutant system. Moreover, it also proves that the Ag-TiO2 hybrid can serve as a promising recyclable SERS-active substrate by virtue of its photocatalytic self-cleaning properties for some specific applications, for instance comparative studies of different species on the same SERS platform, in addition to the economic benefit.

  12. In cellulo phosphorylation of XRCC4 Ser320 by DNA-PK induced by DNA damage

    International Nuclear Information System (INIS)

    Sharma, Mukesh Kumar; Imamichi, Shoji; Fukuchi, Mikoto; Samarth, Ravindra Mahadeo; Tomita, Masanori; Matsumoto, Yoshihisa

    2016-01-01

    XRCC4 is a protein associated with DNA Ligase IV, which is thought to join two DNA ends at the final step of DNA double-strand break repair through non-homologous end joining. In response to treatment with ionizing radiation or DNA damaging agents, XRCC4 undergoes DNA-PK-dependent phosphorylation. Furthermore, Ser260 and Ser320 (or Ser318 in alternatively spliced form) of XRCC4 were identified as the major phosphorylation sites by purified DNA-PK in vitro through mass spectrometry. However, it has not been clear whether these sites are phosphorylated in vivo in response to DNA damage. In the present study, we generated an antibody that reacts with XRCC4 phosphorylated at Ser320 and examined in cellulo phosphorylation status of XRCC4 Ser320. The phosphorylation of XRCC4 Ser320 was induced by γ-ray irradiation and treatment with Zeocin. The phosphorylation of XRCC4 Ser320 was detected even after 1 Gy irradiation and increased in a manner dependent on radiation dose. The phosphorylation was observed immediately after irradiation and remained mostly unchanged for up to 4 h. The phosphorylation was inhibited by DNA-PK inhibitor NU7441 and was undetectable in DNA-PKcs-deficient cells, indicating that the phosphorylation was mainly mediated by DNA-PK. These results suggested potential usefulness of the phosphorylation status of XRCC4 Ser320 as an indicator of DNA-PK functionality in living cells

  13. Au coated PS nanopillars as a highly ordered and reproducible SERS substrate

    Science.gov (United States)

    Kim, Yong-Tae; Schilling, Joerg; Schweizer, Stefan L.; Sauer, Guido; Wehrspohn, Ralf B.

    2017-07-01

    Noble metal nanostructures with nanometer gap size provide strong surface-enhanced Raman scattering (SERS) which can be used to detect trace amounts of chemical and biological molecules. Although several approaches were reported to obtain active SERS substrates, it still remains a challenge to fabricate SERS substrates with high sensitivity and reproducibility using low-cost techniques. In this article, we report on the fabrication of Au sputtered PS nanopillars based on a template synthetic method as highly ordered and reproducible SERS substrates. The SERS substrates are fabricated by anodic aluminum oxide (AAO) template-assisted infiltration of polystyrene (PS) resulting in hemispherical structures, and a following Au sputtering process. The optimum gap size between adjacent PS nanopillars and thickness of the Au layers for high SERS sensitivity are investigated. Using the Au sputtered PS nanopillars as an active SERS substrate, the Raman signal of 4-methylbenzenethiol (4-MBT) with a concentration down to 10-9 M is identified with good signal reproducibility, showing great potential as promising tool for SERS-based detection.

  14. Influence of the OGG1 Ser326Cys polymorphism on oxidatively damaged DNA and repair activity

    DEFF Research Database (Denmark)

    Jensen, Annie Aarup; Løhr, Mille; Eriksen, Louise

    2012-01-01

    of the comet assay. We collected blood samples from 1,019 healthy subjects and genotyped for the OGG1 Ser326Cys polymorphism. We found 49 subjects homozygous for the variant genotype (Cys/Cys) and selected same numbers of age-matched subjects with the heterozygous (Ser/Cys) and homozygous wild-type genotype...

  15. Development of surface enhanced Raman scattering (SERS) spectroscopy monitoring of fuel markers to prevent fraud

    Science.gov (United States)

    Wilkinson, Timothy; Clarkson, John; White, Peter C.; Meakin, Nicholas; McDonald, Ken

    2013-05-01

    Governments often tax fuel products to generate revenues to support and stimulate their economies. They also subsidize the cost of essential fuel products. Fuel taxation and subsidization practices are both subject to fraud. Oil marketing companies also suffer from fuel fraud with loss of legitimate sales and additional quality and liability issues. The use of an advanced marking system to identify and control fraud has been shown to be effective in controlling illegal activity. DeCipher has developed surface enhanced Raman scattering (SERS) spectroscopy as its lead technology for measuring markers in fuel to identify and control malpractice. SERS has many advantages that make it highly suitable for this purpose. The SERS instruments are portable and can be used to monitor fuel at any point in the supply chain. SERS shows high specificity for the marker, with no false positives. Multiple markers can also be detected in a single SERS analysis allowing, for example, specific regional monitoring of fuel. The SERS analysis from fuel is also quick, clear and decisive, with a measurement time of less than 5 minutes. We will present results highlighting our development of the use of a highly stable silver colloid as a SERS substrate to measure the markers at ppb levels. Preliminary results from the use of a solid state SERS substrate to measure fuel markers will also be presented.

  16. SERS detection of the biomarker hydrogen cyanide from Pseudomonas aeruginosa cultures isolated from cystic fibrosis patients

    DEFF Research Database (Denmark)

    Lauridsen, Rikke Kragh; Madsen Sommer, Lea Mette; Johansen, Helle Krogh

    2017-01-01

    . The P. aeruginosa biomarker hydrogen cyanide (HCN) contains a triple bond, which is utilized in this study because of the resulting characteristic C≡N peak at 2135 cm-1 in a Raman spectrum. The Raman signal was enhanced by surface-enhanced Raman spectroscopy (SERS) on a Au-coated SERS substrate. After...

  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. Technology transfer and application of SERS continuous monitor for trace organic compounds

    International Nuclear Information System (INIS)

    Swindle, D.W. Jr.; Vo-Dinh, T.; Yalcintas, M.G.

    1992-01-01

    An in situ-enhanced Raman Scattering (SERS) continuous monitoring system was developed for exciting and collecting SERS signals generated on silver-coated microparticles deposited on a continuously rotating filter-paper support. SERS measurements were successfully conducted for several organic compounds. An in situ SERS fiber-optic system was also developed for exciting and collecting SERS signals generated from a sensing tip having silver-coated microparticles deposited on a glass-plate support. These devices will be very useful in remote identification of unknown chemicals from hazardous waste sites. This patented technology has been licensed from Oak Ridge National Laboratory to an analytical instrumentation firm which is in the process of completing development and marketing these detectors. Advantages to using this technology range from increased safety and sensitivity for detecting hazardous compounds to better statistics and reliable results. During this presentation, efforts of the Environmental Restoration Program to evaluate and support development of this technology will be described

  19. Parameter optimization for Ag-coated TiO2 nanotube arrays as recyclable SERS substrates

    Science.gov (United States)

    Sun, Yuyang; Yang, Lulu; Liao, Fan; Dang, Qian; Shao, Mingwang

    2018-06-01

    The Ag-coated titanium dioxide nanotube arrays (Ag-coated TNTs) are obtained via the deposition of Ag nanoparticles on the two-step anodized TNTs. The wall thickness of TNTs is modulated via finite difference time domain simulation to get the favorable electromagnetic field for surface enhanced Raman scattering (SERS). Ag-coated TNTs with optimal wall thickness of 20 nm were employed as the SERS substrates to detect 2-mercaptobenzoxazole, which show superior detection sensitivity and uniformity. In addition, due to the photocatalysis of TNTs, the SERS substrates could clean themselves and be repeatedly used by photo-degradation of target molecules under the ultra-violet irradiation. The Ag-coated TNTs are a kind of bifunctional SERS substrates which can produce high-quality SERS signals and reuse to reduce the cost.

  20. A Sensitive Gold Nanoplasmonic SERS Quantitative Analysis Method for Sulfate in Serum Using Fullerene as Catalyst

    Directory of Open Access Journals (Sweden)

    Chongning Li

    2018-04-01

    Full Text Available Fullerene exhibited strong catalysis of the redox reaction between HAuCl4 and trisodium citrate to form gold nanoplasmon with a strong surface-enhanced Raman scattering (SERS effect at 1615 cm−1 in the presence of Vitoria blue B molecule probes. When fullerene increased, the SERS peak enhanced linearly due to formation of more AuNPs as substrate. Upon addition of Ba2+, Ba2+ ions adsorb on the fullerene surface to inhibit the catalysis of fullerene that caused the SERS peak decreasing. Analyte SO42− combined with Ba2+ to form stable BaSO4 precipitate to release free fullerene that the catalysis recovered, and the SERS intensity increased linearly. Thus, a new SERS quantitative analysis method was established for the detection of sulfate in serum samples, with a linear range of 0.03–3.4 μM.

  1. A Widely Applicable Silver Sol for TLC Detection with Rich and Stable SERS Features

    Science.gov (United States)

    Zhu, Qingxia; Li, Hao; Lu, Feng; Chai, Yifeng; Yuan, Yongfang

    2016-04-01

    Thin-layer chromatography (TLC) coupled with surface-enhanced Raman spectroscopy (SERS) has gained tremendous popularity in the study of various complex systems. However, the detection of hydrophobic analytes is difficult, and the specificity still needs to be improved. In this study, a SERS-active non-aqueous silver sol which could activate the analytes to produce rich and stable spectral features was rapidly synthesized. Then, the optimized silver nanoparticles (AgNPs)-DMF sol was employed for TLC-SERS detection of hydrophobic (and also hydrophilic) analytes. SERS performance of this sol was superior to that of traditional Lee-Meisel AgNPs due to its high specificity, acceptable stability, and wide applicability. The non-aqueous AgNPs would be suitable for the TLC-SERS method, which shows great promise for applications in food safety assurance, environmental monitoring, medical diagnoses, and many other fields.

  2. Gold dimer nanoantenna with slanted gap for tunable LSPR and improved SERS

    KAUST Repository

    Kessentini, Sameh

    2014-02-13

    We focus on improving the surface-enhanced Raman scattering (SERS) of dimer nanoantenna by tailoring the shape of the coupled nanoantennas extremities from rounded to straight or slanted ones. A numerical model based on the discrete dipole approximation method-taking into account periodicity, adhesion layer, and roughness-is first validated by comparison with localized surface plasmon resonance (LSPR) and SERS experiments on round-edged dimer nanoantennas and then used to investigate the effect of the straight or slanted gap in the dimer antenna. Simulations show that both LSPR and SERS can be tuned by changing the gap slanting angle. The SERS enhancement factor can also be improved by 2 orders of magnitude compared to the one reached using a rounded gap. Therefore, the slanting angle can be used as a new control parameter in the design of SERS substrates to guarantee stronger field confinement and higher sensitivity, especially as its feasibility is demonstrated. © 2014 American Chemical Society.

  3. Gold dimer nanoantenna with slanted gap for tunable LSPR and improved SERS

    KAUST Repository

    Kessentini, Sameh; Barchiesi, Dominique; D'Andrea, Cristiano; Toma, Andrea; Guillot, Nicolas; Di Fabrizio, Enzo M.; Fazio, Barbara; Maragó , Onofrio M.; Gucciardi, Pietro Giuseppe; Lamy De La Chapelle, Marc L.

    2014-01-01

    We focus on improving the surface-enhanced Raman scattering (SERS) of dimer nanoantenna by tailoring the shape of the coupled nanoantennas extremities from rounded to straight or slanted ones. A numerical model based on the discrete dipole approximation method-taking into account periodicity, adhesion layer, and roughness-is first validated by comparison with localized surface plasmon resonance (LSPR) and SERS experiments on round-edged dimer nanoantennas and then used to investigate the effect of the straight or slanted gap in the dimer antenna. Simulations show that both LSPR and SERS can be tuned by changing the gap slanting angle. The SERS enhancement factor can also be improved by 2 orders of magnitude compared to the one reached using a rounded gap. Therefore, the slanting angle can be used as a new control parameter in the design of SERS substrates to guarantee stronger field confinement and higher sensitivity, especially as its feasibility is demonstrated. © 2014 American Chemical Society.

  4. Dynamic phosphorylation of RelA on Ser42 and Ser45 in response to TNFα stimulation regulates DNA binding and transcription.

    Science.gov (United States)

    Lanucara, Francesco; Lam, Connie; Mann, Jelena; Monie, Tom P; Colombo, Stefano A P; Holman, Stephen W; Boyd, James; Dange, Manohar C; Mann, Derek A; White, Michael R H; Eyers, Claire E

    2016-07-01

    The NF-κB signalling module controls transcription through a network of protein kinases such as the IKKs, as well as inhibitory proteins (IκBs) and transcription factors including RelA/p65. Phosphorylation of the NF-κB subunits is critical for dictating system dynamics. Using both non-targeted discovery and quantitative selected reaction monitoring-targeted proteomics, we show that the cytokine TNFα induces dynamic multisite phosphorylation of RelA at a number of previously unidentified residues. Putative roles for many of these phosphorylation sites on RelA were predicted by modelling of various crystal structures. Stoichiometry of phosphorylation determination of Ser45 and Ser42 revealed preferential early phosphorylation of Ser45 in response to TNFα. Quantitative analyses subsequently confirmed differential roles for pSer42 and pSer45 in promoter-specific DNA binding and a role for both of these phosphosites in regulating transcription from the IL-6 promoter. These temporal dynamics suggest that RelA-mediated transcription is likely to be controlled by functionally distinct NF-κB proteoforms carrying different combinations of modifications, rather than a simple 'one modification, one effect' system. © 2016 The Authors.

  5. Research

    African Journals Online (AJOL)

    abp

    2017-05-18

    May 18, 2017 ... available to populations of developing countries [2-5]. In 2013, in. Western and Central Europe and ..... initiation among the infected persons in the community. Addressing stigma and educating ... Lifespan/Tufts/Brown Center for AIDS Research (P30AI042853). Tables. Table 1: Baseline characteristics of ...

  6. Research

    African Journals Online (AJOL)

    abp

    15 févr. 2016 ... présentent un Indice de Masse Corporel (IMC) normal, les autres femmes sont soit ..... In The health belief model and personal health behavior, edited by MH ... Evaluation of the Osteoporosis Health Belief Scale. Research in.

  7. Research

    African Journals Online (AJOL)

    2017-03-14

    Mar 14, 2017 ... R Ebrahim,1 MSc (Dent); H Julie,2 MPH, MCur, PhD. 1 Extended ... and research is applied to develop and sustain society.[5]. Methods .... service they want, not the service we want to give whether they want it or. Co math. G.

  8. Research

    African Journals Online (AJOL)

    abp

    2017-11-24

    Nov 24, 2017 ... Page number not for citation purposes. 1. Prevalence and determinants of common mental ..... illnesses were smoke cigarette in the last 3 months that make prevalence of tobacco use 38.2%. ..... Okasha A, Karam E.Mental health services and research in the. Arab world. Acta Psychiatrica Scandinavica.

  9. Research

    African Journals Online (AJOL)

    abp

    2014-04-21

    Apr 21, 2014 ... Prospective assessment of the risk of obstructive sleep apnea in ... Faculty of Clinical Sciences, College of Medicine, University of .... University Teaching Hospital Health Research Ethics Committee ... BANG, Berlin questionnaire and the American Society of .... The epidemiology of adult obstructive sleep.

  10. Research

    African Journals Online (AJOL)

    abp

    2016-02-01

    Feb 1, 2016 ... University Hospital, DK-5000 Odense, Denmark, 3Center for Global Health, Institute of Clinical Research, University of Southern Denmark, DK-5000. Odense .... BHP is a Danish-Guinean Demographic Surveillance Site with a study-area .... variables such as age groups, previous military duty, history of.

  11. Research

    African Journals Online (AJOL)

    abp

    2015-06-24

    Jun 24, 2015 ... related immunosuppression, previous history of TB, and pause in treatment [6]. In Brazil, researchers .... treatment, use of traditional medicines or herbs, history of TB drug side effects and treatment delay). ..... therapy for pulmonary tuberculosis in Lima Ciudad, Peru. International journal of tuberculosis and ...

  12. Research

    African Journals Online (AJOL)

    Research. May 2016, Vol. 8, No. 1 AJHPE 37. Students who enrol in occupational therapy (OT) at the. University of Kwa Zulu-Natal (UKZN), Durban, South Africa ... The latter may include becoming familiar with the disintegrating social systems in primary .... They also lacked the skills needed to adapt sessions and failed to ...

  13. Research

    African Journals Online (AJOL)

    ebutamanya

    2015-06-22

    Jun 22, 2015 ... collaboration with Makerere University, School of Public Health. We acknowledge The Family Health Research and Development Centre. (FHRDC) Uganda. Supported by Bill & Melinda Gates Institute for. Population & Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, ...

  14. Research

    African Journals Online (AJOL)

    However, a focus on competence alone is inadequate to produce graduates who are capable of adapting to the changing needs of health systems. While knowledge and technical ... shared their responses to guided questions. There were three sessions; after each session the researcher aggregated participant responses ...

  15. Research

    African Journals Online (AJOL)

    abp

    2014-01-31

    Jan 31, 2014 ... by Hazarika in a population-based study in India. The researcher noted that patients' preference to the private health facilities was due mainly to their dissatisfaction with the services in the public health facilities [11]. Furthermore, the quality of the services in the private health facilities could also be a major ...

  16. Research

    African Journals Online (AJOL)

    2018-03-20

    Mar 20, 2018 ... student health professionals in various institutions, both in South Africa. (SA) and internationally. ... field include dentists, dental therapists and oral hygienists in training, .... The College of Health Sciences at UKZN has four schools: clinical ..... Journal of Emerging Trends in Educational Research and Policy ...

  17. Research

    African Journals Online (AJOL)

    abp

    2017-09-14

    Sep 14, 2017 ... Abstract. Introduction: Medical and dental students are a high-risk group for hepatitis B virus (HBV) infection which is an ... The Pan African Medical Journal - ISSN 1937-8688. ... Research ... in the College of Health Sciences and clinical students (years four to .... Hepatology International.2017 Jan; 11(1):.

  18. Research

    African Journals Online (AJOL)

    abp

    2015-01-19

    Jan 19, 2015 ... One research assistant was available to assist the learners and to answer questions while they completed the questionnaires during a classroom period. ..... PubMed | Google Scholar. 4. Hall PA, Holmqvist M, Sherry SB. Risky adolescent sexual behaviour: A psychological perspective for primary care.

  19. Science Education Research vs. Physics Education Research: A Structural Comparison

    Science.gov (United States)

    Akarsu, Bayram

    2010-01-01

    The main goal of this article is to introduce physics education research (PER) to researchers in other fields. Topics include discussion of differences between science education research (SER) and physics education research (PER), physics educators, research design and methodology in physics education research and current research traditions and…

  20. Cyanuric acid hydrolase from Azorhizobium caulinodans ORS 571: crystal structure and insights into a new class of Ser-Lys dyad proteins.

    Directory of Open Access Journals (Sweden)

    Seunghee Cho

    Full Text Available Cyanuric acid hydrolase (CAH catalyzes the hydrolytic ring-opening of cyanuric acid (2,4,6-trihydroxy-1,3,5-triazine, an intermediate in s-triazine bacterial degradation and a by-product from disinfection with trichloroisocyanuric acid. In the present study, an X-ray crystal structure of the CAH-barbituric acid inhibitor complex from Azorhizobium caulinodans ORS 571 has been determined at 2.7 Å resolution. The CAH protein fold consists of three structurally homologous domains forming a β-barrel-like structure with external α-helices that result in a three-fold symmetry, a dominant feature of the structure and active site that mirrors the three-fold symmetrical shape of the substrate cyanuric acid. The active site structure of CAH is similar to that of the recently determined AtzD with three pairs of active site Ser-Lys dyads. In order to determine the role of each Ser-Lys dyad in catalysis, a mutational study using a highly sensitive, enzyme-coupled assay was conducted. The 10⁹-fold loss of activity by the S226A mutant was at least ten times lower than that of the S79A and S333A mutants. In addition, bioinformatics analysis revealed the Ser226/Lys156 dyad as the only absolutely conserved dyad in the CAH/barbiturase family. These data suggest that Lys156 activates the Ser226 nucleophile which can then attack the substrate carbonyl. Our combination of structural, mutational, and bioinformatics analyses differentiates this study and provides experimental data for mechanistic insights into this unique protein family.

  1. ser uden pant: Cans without a mortgage

    OpenAIRE

    Rostrup, Emil; Mouritzen, Jeppe; Wagner, Sara; Skovlund, Kristian; Rein, Jakob; Engholm, Simon

    2013-01-01

    This research aims to investigate the possibility of changing people’s recycle behaviour, with a focus on cans without a mortgage, through a design. In order to investigate this possibility, a needs assessment was carried out, where the specific demands of waste plants, consumers, retail trade and environment were taken into consideration. The demands of the waste plants as well as the demand of the retail trade were found by collecting empiricism from various websites. The needs of the consu...

  2. Analytical characterization using surface-enhanced Raman scattering (SERS) and microfluidic sampling

    International Nuclear Information System (INIS)

    Wang, Chao; Yu, Chenxu

    2015-01-01

    With the rapid development of analytical techniques, it has become much easier to detect chemical and biological analytes, even at very low detection limits. In recent years, techniques based on vibrational spectroscopy, such as surface enhanced Raman spectroscopy (SERS), have been developed for non-destructive detection of pathogenic microorganisms. SERS is a highly sensitive analytical tool that can be used to characterize chemical and biological analytes interacting with SERS-active substrates. However, it has always been a challenge to obtain consistent and reproducible SERS spectroscopic results at complicated experimental conditions. Microfluidics, a tool for highly precise manipulation of small volume liquid samples, can be used to overcome the major drawbacks of SERS-based techniques. High reproducibility of SERS measurement could be obtained in continuous flow generated inside microfluidic devices. This article provides a thorough review of the principles, concepts and methods of SERS-microfluidic platforms, and the applications of such platforms in trace analysis of chemical and biological analytes. (topical review)

  3. Development of an optical fiber SERS microprobe for minimally invasive sensing applications

    Science.gov (United States)

    Mamun, Md Abdullah Al; Juodkazis, Saulius; Mahadevan-Jansen, Anita; Stoddart, Paul R.

    2018-02-01

    Numerous potential biomedical sensing applications of surface-enhanced Raman scattering (SERS) have been reported, but its practical use has been limited by the lack of a robust sensing platform. Optical fiber SERS probes show great promise, but are limited by the prominent silica Raman background, which requires the use of bulky optics for filtering the signal collection and excitation delivery paths. In the present study, a SERS microprobe has been designed and developed to eliminate the bottlenecks outlined above. For efficient excitation and delivery of the SERS signal, both hollow core photonic crystal fiber and double clad fiber have been investigated. While the hollow core fiber was still found to have excessive silica background, the double clad fiber allows efficient signal collection via the multi-mode inner cladding. A micro filtering mechanism has been designed, which can be integrated into the tip of the optical fiber SERS probe, providing filtering to suppress silica Raman background and thus avoiding the need for bulky optics. The design also assists in the efficient collection of SERS signal from the sample by rejecting Rayleigh scattered light from the sample. Optical fiber cleaving using ultra-short laser pulses was tested for improved control of the fiber tip geometry. With this miniaturized and integrated filtering mechanism, it is expected that the developed probe will promote the use of SERS for minimally invasive biomedical monitoring and sensing applications in future. The probe could potentially be placed inside a small gauge hypodermic needle and would be compatible with handheld portable spectrometers.

  4. PKCδ-mediated IRS-1 Ser24 phosphorylation negatively regulates IRS-1 function

    International Nuclear Information System (INIS)

    Greene, Michael W.; Ruhoff, Mary S.; Roth, Richard A.; Kim, Jeong-a; Quon, Michael J.; Krause, Jean A.

    2006-01-01

    The IRS-1 PH and PTB domains are essential for insulin-stimulated IRS-1 Tyr phosphorylation and insulin signaling, while Ser/Thr phosphorylation of IRS-1 disrupts these signaling events. To investigate consensus PKC phosphorylation sites in the PH-PTB domains of human IRS-1, we changed Ser24, Ser58, and Thr191 to Ala (3A) or Glu (3E), to block or mimic phosphorylation, respectively. The 3A mutant abrogated the inhibitory effect of PKCδ on insulin-stimulated IRS-1 Tyr phosphorylation, while reductions in insulin-stimulated IRS-1 Tyr phosphorylation, cellular proliferation, and Akt activation were observed with the 3E mutant. When single Glu mutants were tested, the Ser24 to Glu mutant had the greatest inhibitory effect on insulin-stimulated IRS-1 Tyr phosphorylation. PKCδ-mediated IRS-1 Ser24 phosphorylation was confirmed in cells with PKCδ catalytic domain mutants and by an RNAi method. Mechanistic studies revealed that IRS-1 with Ala and Glu point mutations at Ser24 impaired phosphatidylinositol-4,5-bisphosphate binding. In summary, our data are consistent with the hypothesis that Ser24 is a negative regulatory phosphorylation site in IRS-1

  5. Phospho-Bcl-xL(Ser62) influences spindle assembly and chromosome segregation during mitosis.

    Science.gov (United States)

    Wang, Jianfang; Beauchemin, Myriam; Bertrand, Richard

    2014-01-01

    Functional analysis of a series of phosphorylation mutants reveals that Bcl-xL(Ser62Ala) influences cell entry into anaphase and mitotic exit in taxol-exposed cells compared with cells expressing wild-type Bcl-xL or a series of other phosphorylation mutants, an effect that appears to be independent of its anti-apoptotic activity. During normal mitosis progression, Bcl-xL(Ser62) is strongly phosphorylated by PLK1 and MAPK14/SAPKp38α at the prometaphase, metaphase, and the anaphase boundaries, while it is de-phosphorylated at telophase and cytokinesis. Phospho-Bcl-xL(Ser62) localizes in centrosomes with γ-tubulin and in the mitotic cytosol with some spindle-assembly checkpoint signaling components, including PLK1, BubR1, and Mad2. In taxol- and nocodazole-exposed cells, phospho-Bcl-xL(Ser62) also binds to Cdc20- Mad2-, BubR1-, and Bub3-bound complexes, while Bcl-xL(Ser62Ala) does not. Silencing Bcl-xL expression and expressing the phosphorylation mutant Bcl-xL(Ser62Ala) lead to an increased number of cells harboring mitotic spindle defects including multipolar spindle, chromosome lagging and bridging, aneuploidy with micro-, bi-, or multi-nucleated cells, and cells that fail to resolve undergo mitosis within 6 h. Together, the data indicate that during mitosis, Bcl-xL(Ser62) phosphorylation impacts on spindle assembly and chromosome segregation, influencing chromosome stability. Observations of mitotic cells harboring aneuploidy with micro-, bi-, or multi-nucleated cells, and cells that fail to resolve undergo mitosis within 6 h were also made with cells expressing the phosphorylation mutant Bcl-xL(Ser49Ala) and dual mutant Bcl-xL(Ser49/62Ala).

  6. Teenagers Want to be Mothers... But... Las adolescentes quieren ser madres... pero... Adolescentes desejam ser mães… mas…

    Directory of Open Access Journals (Sweden)

    VIRGINIA INÉS SOTO LESMES

    2010-10-01

    álisis emergieron siete categorías: "Embarazo inesperado", "Asumiendo el embarazo", "Experimentando formas de cuidarse", "Padeciendo pérdidas por el embarazo", "Culpándose por el embarazo", "Resistiéndose al aborto" y "Reedificando redes de apoyo". Emerge la categoría central y por ende el planteamiento hipotético afirmando que las adolescentes están "Deseando el embarazo pero no tan pronto". Se parte del concepto ambivalencia como hilo conductor para mostrar cómo evoluciona esta secuencia de acciones/interacciones en respuesta a la experiencia del embarazo y cómo se alinean según las condiciones y cambios que han experimentado en su contexto también ambivalente. Se concluye que las adolescentes embarazadas delegan en el hombre la protección frente a un posible embarazo, sin embargo, cuando se enteran de estar embarazadas los excluyen y excusan de cualquier responsabilidad. Asocian cuidado con cambios en sus comportamientos sociales sin ser significativos los cambios físicos. El 21% de las participantes, están pasando por su segundo embarazo, indicador alarmante para el bienestar de estas jóvenes y sus hijos por nacer. La relación padres-adolescente se afianza durante el embarazo, aunque sus madres cuando tuvieron conocimiento de que sus hijas ya habían iniciado su actividad sexual, lo ignoraron. Se hace un llamado urgente a innovar estrategias de cuidado individualizado y contextualizado.Este estudo foi realizado com base teórica e objetivou o seguinte: descrever a experiência de gravidez e gerar uma hipótese sobre esse processo em um grupo de adolescentes; coletar dados através de entrevistas em profundidade realizadas em 30 adolescentes grávidas. Sete categorias surgiram da analise: "Gravidez inesperada"; "Assumindo a gravidez", "Experimentando métodos de prevenção", "Sofrendo perdas pela gravidez", "Sentindo culpa pela gravidez", "Rejeitando o aborto" e "Reconstruindo redes de apoio". Surge a categoria central e, portanto, a hipótese afirmando que as

  7. eenagers Want to be Mothers... But... Las adolescentes quieren ser madres... pero... Adolescentes desejam ser mães… mas…

    Directory of Open Access Journals (Sweden)

    DURÁN DE VILLALOBOS MARÍA MERCEDES

    2010-10-01

    entrevistas a profundidad a 30 adolescentes gestantes, Del análisis emergieron siete categorías: “Embarazo inesperado”, “Asumiendo el embarazo”, “Experimentando formas de cuidarse”, “Padeciendo pérdidas por el embarazo”, “Culpándose por el embarazo”, “Resistiéndose al aborto” y “Reedificando redes de apoyo”. Emerge la categoría central y por ende el planteamiento hipotético afirmando que las adolescentes están “Deseando el embarazo pero no tan pronto”. Se parte del concepto ambivalencia como hilo conductor para mostrar cómo evoluciona esta secuencia de acciones/interacciones en respuesta a la experiencia del embarazo y cómo se alinean según las condiciones y cambios que han experimentado en su contexto también ambivalente.

    Se concluye que las adolescentes embarazadas delegan en el hombre la protección frente a un posible embarazo, sin embargo, cuando se enteran de estar embarazadas los excluyen y excusan de cualquier responsabilidad. Asocian cuidado con cambios en sus comportamientos sociales sin ser significativos los cambios físicos. El 21% de las participantes, están pasando por su segundo embarazo, indicador alarmante para el bienestar de estas jóvenes y sus hijos por nacer. La relación padres-adolescente se afianza durante el embarazo, aunque sus madres cuando tuvieron conocimiento de que sus hijas ya habían iniciado su actividad sexual, lo ignoraron. Se hace un llamado urgente a innovar estrategias de cuidado individualizado y contextualizado.

    Este estudo foi realizado com base teórica e objetivou o seguinte: descrever a experiência de gravidez e gerar uma hipótese sobre esse processo em um grupo de adolescentes; coletar dados através de entrevistas em profundidade realizadas em 30 adolescentes grávidas.

    Sete categorias surgiram da analise: “Gravidez inesperada”; “Assumindo a gravidez”, “Experimentando métodos de prevenção”,

  8. Design of SERS nanoprobes for Raman imaging: materials, critical factors and architectures.

    Science.gov (United States)

    Li, Mingwang; Qiu, Yuanyuan; Fan, Chenchen; Cui, Kai; Zhang, Yongming; Xiao, Zeyu

    2018-05-01

    Raman imaging yields high specificity and sensitivity when compared to other imaging modalities, mainly due to its fingerprint signature. However, intrinsic Raman signals are weak, thus limiting medical applications of Raman imaging. By adsorbing Raman molecules onto specific nanostructures such as noble metals, Raman signals can be significantly enhanced, termed surface-enhanced Raman scattering (SERS). Recent years have witnessed great interest in the development of SERS nanoprobes for Raman imaging. Rationally designed SERS nanoprobes have greatly enhanced Raman signals by several orders of magnitude, thus showing great potential for biomedical applications. In this review we elaborate on recent progress in design strategies with emphasis on material properties, modifying factors, and structural parameters.

  9. Nanosphere Lithography on Fiber: Towards Engineered Lab-On-Fiber SERS Optrodes

    Directory of Open Access Journals (Sweden)

    Giuseppe Quero

    2018-02-01

    Full Text Available In this paper we report on the engineering of repeatable surface enhanced Raman scattering (SERS optical fiber sensor devices (optrodes, as realized through nanosphere lithography. The Lab-on-Fiber SERS optrode consists of polystyrene nanospheres in a close-packed arrays configuration covered by a thin film of gold on the optical fiber tip. The SERS surfaces were fabricated by using a nanosphere lithography approach that is already demonstrated as able to produce highly repeatable patterns on the fiber tip. In order to engineer and optimize the SERS probes, we first evaluated and compared the SERS performances in terms of Enhancement Factor (EF pertaining to different patterns with different nanosphere diameters and gold thicknesses. To this aim, the EF of SERS surfaces with a pitch of 500, 750 and 1000 nm, and gold films of 20, 30 and 40 nm have been retrieved, adopting the SERS signal of a monolayer of biphenyl-4-thiol (BPT as a reliable benchmark. The analysis allowed us to identify of the most promising SERS platform: for the samples with nanospheres diameter of 500 nm and gold thickness of 30 nm, we measured values of EF of 4 × 105, which is comparable with state-of-the-art SERS EF achievable with highly performing colloidal gold nanoparticles. The reproducibility of the SERS enhancement was thoroughly evaluated. In particular, the SERS intensity revealed intra-sample (i.e., between different spatial regions of a selected substrate and inter-sample (i.e., between regions of different substrates repeatability, with a relative standard deviation lower than 9 and 15%, respectively. Finally, in order to determine the most suitable optical fiber probe, in terms of excitation/collection efficiency and Raman background, we selected several commercially available optical fibers and tested them with a BPT solution used as benchmark. A fiber probe with a pure silica core of 200 µm diameter and high numerical aperture (i.e., 0.5 was found to be the

  10. [Preparation of a kind of SERS-active substrates for spot fast analysis].

    Science.gov (United States)

    Ji, Nan; Li, Zhi-Shi; Zhao, Bing; Zou, Bo

    2013-02-01

    A kind of SERS-active substrates was prepared using chemical self-assembly method, aiming at spot fast analysis using portable Raman spectrometer. PDDA was first absorbed on the inner wall of vials, and then Ag colloids were assembled on the inner wall. UV-Vis spectra and Raman spectra of two kinds of blank vials were investigated and the transparent vials were thought to be better for SERS-vials. UV-Vis spectra were used to monitor the assembly process of Ag colloids. SERS activity of our substrates was characterized using p-ATP as probing molecules.

  11. Unidad did??ctica: concepciones filos??ficas del ser humano

    OpenAIRE

    Mart??nez Moreno, Roc??o

    2012-01-01

    Esta unidad did??ctica se justifica en tanto que ofrece la posibilidad de estudiar al ser humano desde varias perspectivas filos??ficas, consider??ndolo desde sus diferentes dimensiones. Esto nos aleja del dogmatismo o la creencia de que el ser humano es un constructo cerrado y definible. Quiz?? desde las ciencias nos acerquemos a una visi??n de lo que ??ste es en su versi??n mec??nica o biol??gica; pero no debemos olvidar que el ser humano tambi??n est?? sujeto al paso del tiempo, a la socie...

  12. Synthesis of silver nanocubes as a SERS substrate for the determination of pesticide paraoxon and thiram

    Science.gov (United States)

    Wang, Bin; Zhang, Li; Zhou, Xia

    2014-03-01

    The silver cube-like nanostructure with uniform size and high yield have been synthesized through the rapid sulfide-mediated polyol method. The morphology, structure and optical properties of the as-prepared silver nanocubes were characterized by UV-Visible spectroscopy, field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). The Surface-Enhanced Raman Scattering (SERS) performance of the as-prepared Ag nanocubes was characterized by crystal violet (CV) as the probe molecules. Furthermore, the low levels of thiram and pesticide paraoxon can be detected by the SERS technique, which shows that the silver nanocubes as a SERS substrate have excellent sensitivity and reproducibility.

  13. Application of surface-enhanced Raman spectroscopy (SERS) for cleaning verification in pharmaceutical manufacture.

    Science.gov (United States)

    Corrigan, Damion K; Cauchi, Michael; Piletsky, Sergey; Mccrossen, Sean

    2009-01-01

    Cleaning verification is the process by which pharmaceutical manufacturing equipment is determined as sufficiently clean to allow manufacture to continue. Surface-enhanced Raman spectroscopy (SERS) is a very sensitive spectroscopic technique capable of detection at levels appropriate for cleaning verification. In this paper, commercially available Klarite SERS substrates were employed in order to obtain the necessary enhancement of signal for the identification of chemical species at concentrations of 1 to 10 ng/cm2, which are relevant to cleaning verification. The SERS approach was combined with principal component analysis in the identification of drug compounds recovered from a contaminated steel surface.

  14. Visiones sobre la alteridad: la lectura sartreana de Ser y tiempo

    OpenAIRE

    Szeftel, Micaela

    2011-01-01

    Al abordar el estudio del Para-otro en El Ser y la Nada, Sartre reconoce la astucia que Heidegger tuvo al haber enunciado la “realidad-humana” como una relación de ser. La oposición entre sujeto y objeto, en la cual las teorías del conocimiento encuentran no sólo el fundamento del existir humano sino también el punto de partida para la pregunta por el ser, es reemplazada por un vínculo fundado en una esfera pre-ontológica. Mientras que Sartre considera que tanto Hegel como Husserl han quedado...

  15. Following the Dynamics of pH in Endosomes of Live Cells with SERS Nanosensors

    DEFF Research Database (Denmark)

    Kneipp, J.; Kneipp, Harald; Wittig, B.

    2010-01-01

    The surface enhanced Raman scattering (SERS) spectrum of a reporter molecule attached to gold or silver nanostructures, which is pH-sensitive, can deliver information on the local pH in the environment of the nanostructure. Here, we demonstrate the use of a mobile SERS nanosensor made from gold...... nanaoaggregates and 4-mercaptobenzoic acid (pMBA) attached as a reporter for monitoring changes in local pH of the cellular compartments of living NIH/3T3 cells. We show that SERS nanosensors enable the dynamics of local pH in individual live cells to be followed at subendosomal resolution in a timeline...

  16. Development of a paper-based vertical flow SERS assay for citrulline detection using aptamer-conjugated gold nanoparticles

    Science.gov (United States)

    Locke, Andrea; Deutz, Nicolaas; Coté, Gerard

    2018-02-01

    Research toward development of point-of-care (POC) technologies is emerging as a means for diagnosis and monitoring of patients outside the hospital. These POC devices typically utilize assays capable of detecting low level biomarkers indicative of specific diseases. L-citrulline, an α-amino acid produced in the intestinal mucosa cells, is one such biomarker typically found circulating within the plasma at physiological concentrations of 40 μM. Researchers have found that intestinal enterocyte malfunction causes its level to be significantly lowered, establishing it as a potential diagnostic biomarker for gut function. Our research group has proposed the development of a surface enhanced Raman spectroscopy (SERS) based assay, using vertical flow paper fluidics, for citrulline detection. The assay consists of a fluorescently active, Raman reporter labeled aptamer conjugated on gold nanoparticles. The aptamer changes its confirmation on binding to its target, which in turn changes the distance between the Raman active molecule and the nanoparticle surface. These particles were embedded within a portable chip consisting of cellulose-based paper. After the chips were loaded with different concentrations of free L-citrulline in phosphate buffer, time was given for the assay to interact with the sample. A handheld Raman spectrometer (638 nm; Ocean Optics) was used to measure the SERS intensity. Results showed decrease in intensity with increasing concentration of L-citrulline (0-50μM).

  17. Comparison of time-gated surface-enhanced Raman spectroscopy (TG-SERS) and classical SERS based monitoring of Escherichia coli cultivation samples.

    Science.gov (United States)

    Kögler, Martin; Paul, Andrea; Anane, Emmanuel; Birkholz, Mario; Bunker, Alex; Viitala, Tapani; Maiwald, Michael; Junne, Stefan; Neubauer, Peter

    2018-06-08

    The application of Raman spectroscopy as a monitoring technique for bioprocesses is severely limited by a large background signal originating from fluorescing compounds in the culture media. Here we compare time-gated Raman (TG-Raman)-, continuous wave NIR-process Raman (NIR-Raman) and continuous wave micro-Raman (micro-Raman) approaches in combination with surface enhanced Raman spectroscopy (SERS) for their potential to overcome this limit. For that purpose, we monitored metabolite concentrations of Escherichia coli bioreactor cultivations in cell-free supernatant samples. We investigated concentration transients of glucose, acetate, AMP and cAMP at alternating substrate availability, from deficiency to excess. Raman and SERS signals were compared to off-line metabolite analysis of carbohydrates, carboxylic acids and nucleotides. Results demonstrate that SERS, in almost all cases, led to a higher number of identifiable signals and better resolved spectra. Spectra derived from the TG-Raman were comparable to those of micro-Raman resulting in well-discernable Raman peaks, which allowed for the identification of a higher number of compounds. In contrast, NIR-Raman provided a superior performance for the quantitative evaluation of analytes, both with and without SERS nanoparticles when using multivariate data analysis. This article is protected by copyright. All rights reserved. © 2018 American Institute of Chemical Engineers.

  18. SERS and in situ SERS spectroscopy of riboflavin adsorbed on silver, gold and copper substrates. Elucidation of variability of surface orientation based on both experimental and theoretical approach

    Science.gov (United States)

    Dendisová-Vyškovská, Marcela; Kokaislová, Alžběta; Ončák, Milan; Matějka, Pavel

    2013-04-01

    Surface-enhanced Raman scattering and in situ surface-enhanced Raman scattering spectra have been collected to study influences of (i) used metal and (ii) applied electrode potential on orientation of adsorbed riboflavin molecules. Special in situ SERS spectroelectrochemical cell was used to obtain in situ SERS spectra of riboflavin adsorbed on silver, gold and copper nanostructured surfaces. Varying electrode potential was applied in discrete steps forming a cycle from positive values to negative and backward. Observed spectral features in in situ SERS spectra, measured at alternate potentials, have been changing very significantly and the spectra have been compared with SERS spectra of riboflavin measured ex situ. Raman spectra of single riboflavin molecule in the vicinity to metal (Ag, Au and Cu) clusters have been calculated for different mutual positions. The results demonstrate significant changes of bands intensities which can be correlated with experimental spectra measured at different potentials. Thus, the orientation of riboflavin molecules adsorbed on metal surfaces can be elucidated. It is influenced definitely by the value of applied potential. Furthermore, the riboflavin adsorption orientation on the surface depends on the used metal. Adsorption geometries on the copper substrates are more diverse in comparison with the orientations on silver and gold substrates.

  19. Nanosphere Templating Through Controlled Evaporation: A High Throughput Method For Building SERS Substrates

    Science.gov (United States)

    Alexander, Kristen; Hampton, Meredith; Lopez, Rene; Desimone, Joseph

    2009-03-01

    When a pair of noble metal nanoparticles are brought close together, the plasmonic properties of the pair (known as a ``dimer'') give rise to intense electric field enhancements in the interstitial gap. These fields present a simple yet exquisitely sensitive system for performing single molecule surface-enhanced Raman spectroscopy (SM-SERS). Problems associated with current fabrication methods of SERS-active substrates include reproducibility issues, high cost of production and low throughput. In this study, we present a novel method for the high throughput fabrication of high quality SERS substrates. Using a polymer templating technique followed by the placement of thiolated nanoparticles through meniscus force deposition, we are able to fabricate large arrays of identical, uniformly spaced dimers in a quick, reproducible manner. Subsequent theoretical and experimental studies have confirmed the strong dependence of the SERS enhancement on both substrate geometry (e.g. dimer size, shape and gap size) and the polarization of the excitation source.

  20. Self-catalytic stabilized Ag-Cu nanoparticles with tailored SERS response for plasmonic photocatalysis

    Science.gov (United States)

    He, Lili; Liu, Changqing; Tang, Jia; Zhou, Youchen; Yang, Hui; Liu, Ruiyu; Hu, Jiugang

    2018-03-01

    In-situ SERS monitoring of direct plasmon-driven photocatalysis was achieved using relatively earth-abundant Cu NPs following their decoration with tiny amounts of silver, which promoted excellent SERS and high catalytic activity. The SERS and catalytic performance of the Ag-Cu NPs can be tuned by changing their composition. In particular, it was found that the surface oxidation state of copper could be switched to its metallic state via self-plasmon catalysis under laser irradiation, highlighting the potential of air-unstable copper NPs as stable plasmonic catalysts. These dual functional Ag-Cu NPs were used for SERS real-time monitoring of plasmon-driven photocatalysis reactions involving the degradation of Rhodamine 6G and the dimerization of 4-nitrothiophenol. The corresponding catalytic reaction mechanisms were discussed.

  1. Stilbazolium Merocyanine Dye Determination in Different Solutions, Concentrations and Colloids Using SERS

    DEFF Research Database (Denmark)

    Pajchrowski, Grzegorz; Abdali, Salim; Nørbygaard, Thomas

    2006-01-01

    Surface Enhanced Raman Scattering (SERS) measurements were carried out on stilbazolium merocyanine dye in methanol and pyridine solvents. Both solutions were measured in series of concentrations, covering a range of 5·10-5 M to 5·10-8 M. In these measurements Ag and Au colloids were used and the ......Surface Enhanced Raman Scattering (SERS) measurements were carried out on stilbazolium merocyanine dye in methanol and pyridine solvents. Both solutions were measured in series of concentrations, covering a range of 5·10-5 M to 5·10-8 M. In these measurements Ag and Au colloids were used...... report here on the success of using SERS to obtain Raman spectra of merocyanine dye at very low concentration in an attempt of new approach, which can be used for further investigations of the dye. The SERS spectra will here be reported and the results from different solutions, colloids, concentrations...

  2. P-Ser-HPr-a link between carbon metabolism and the virulence of some pathogenic bacteria

    DEFF Research Database (Denmark)

    Mijakovic, Ivan

    2005-01-01

    HPr kinase/phosphorylase phosphorylates HPr, a phosphocarrier protein of the phosphoenolpyruvate:carbohydrate phosphotransferase system, at serine-46. P-Ser-HPr is the central regulator of carbon metabolism in Gram-positive bacteria, but also plays a role in virulence development of certain...... pathogens. In Listeria monocytogenes, several virulence genes, which depend on the transcription activator PrfA, are repressed by glucose, fructose, etc., in a catabolite repressor (CcpA)-independent mechanism. However, the catabolite co-repressor P-Ser-HPr was found to inhibit the activity of Prf...... is preceded by an operator site, which serves as target for the CcpA/P-Ser-HPr complex. Numerous Gram-negative pathogens also contain hprK, which is often organised in an operon with transcription regulators necessary for the development of virulence, indicating that in these organisms P-Ser-HPr also plays...

  3. Monitoring prion protein expression in complex biological samples by SERS for diagnostic applications

    International Nuclear Information System (INIS)

    Manno, D; Filippo, E; Fiore, R; Serra, A; Urso, E; Rizzello, A; Maffia, M

    2010-01-01

    Surface-enhanced Raman spectroscopy (SERS) allows a new insight into the analysis of cell physiology. In this work, the difficulty of producing suitable substrates that, besides permitting the amplification of the Raman signal, do not interact with the biological material causing alteration, has been overcome by a combined method of hydrothermal green synthesis and thermal annealing. The SERS analysis of the cell membrane has been performed with special attention to the cellular prion protein PrP C . In addition, SERS has also been used to reveal the prion protein-Cu(II) interaction in four different cell models (B104, SH-SY5Y, GN11, HeLa), expressing PrP C at different levels. A significant implication of the current work consists of the intriguing possibility of revealing and quantifying prion protein expression in complex biological samples by a cheap SERS-based method, replacing the expensive and time-consuming immuno-assay systems commonly employed.

  4. Water Ser - areng läbi torude ja üle kraavide / Ain Alvela

    Index Scriptorium Estoniae

    Alvela, Ain, 1967-

    2007-01-01

    1992. aastal asutatud vee- ja kanalisatsioonitorustike paigaldamisele spetsialiseerunud perefirma AS Water Ser on kasvanud rahvusvaheliselt mainekaks kontserniks. Vt. samas: Perefirma arengu kronoloogia; Amet sai alguse teismelise eas kraavikaevamisest. Kommenteerivad Andrus Piir ja Toomas Kapp

  5. SERS imaging of cell-surface biomolecules metabolically labeled with bioorthogonal Raman reporters.

    Science.gov (United States)

    Xiao, Ming; Lin, Liang; Li, Zefan; Liu, Jie; Hong, Senlian; Li, Yaya; Zheng, Meiling; Duan, Xuanming; Chen, Xing

    2014-08-01

    Live imaging of biomolecules with high specificity and sensitivity as well as minimal perturbation is essential for studying cellular processes. Here, we report the development of a bioorthogonal surface-enhanced Raman scattering (SERS) imaging approach that exploits small Raman reporters for visualizing cell-surface biomolecules. The cells were cultured and imaged by SERS microscopy on arrays of Raman-enhancing nanoparticles coated on silicon wafers or glass slides. The Raman reporters including azides, alkynes, and carbondeuterium bonds are small in size and spectroscopically bioorthogonal (background-free). We demonstrated that various cell-surface biomolecules including proteins, glycans, and lipids were metabolically incorporated with the corresponding precursors bearing a Raman reporter and visualized by SERS microscopy. The coupling of SERS microscopy with bioorthogonal Raman reporters expands the capabilities of live-cell microscopy beyond the modalities of fluorescence and label-free imaging. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. La luminosa sed: Esbozo de un itinerario de la manifestación del ser como deseo de ser al Dios deseante que viene a nuestro encuentro

    Directory of Open Access Journals (Sweden)

    Alberto Toutin

    2009-01-01

    Full Text Available En este artículo se presenta un primer atisbo de un itinerario de pensamiento que busca articular, por un lado, una comprensión de la poesía en Octavio Paz como manifestación del ser humano como apertura al otro, como deseo de ser y, por otro, la comprensión en Hans Urs von Balthasar del acontecimiento de la automanifestación de Dios, como expresión de su deseo de encuentro con el ser humano y que para ello adopta arriesgada y creativamente su lenguaje en la diversidad de sus expresiones. Con ello tan sólo queremos poner algunas bases para una poética teológica, ya iniciada tanto por Dios como por el hablar del ser humano, y que llama de ella misma a ser continuada y profundizada.In this article, the author presents a first glimpse of an itinerary of thought that seeks to articulate, on the one hand, an understanding of poetry by Octavio Paz as a manifestation of the human being as openness to the other and as desire for being and, on the other hand, Hans Urs von Balthasar's understanding of the event of God's self-manifestation as the expression of His desire to meet the human being and, to that end, adopting, with risk and creativity, the human being's language in all the diversity of its expressions. With that, the author only wants to lay some foundations for a theological poetics, already initiated as much by God as by the speech of the human being, and which calls from its own self to be continuous and deepened.

  7. Neighboring phosphoSer-Pro motifs in the undefined domain of IRAK1 impart bivalent advantage for Pin1 binding.

    Science.gov (United States)

    Rogals, Monique J; Greenwood, Alexander I; Kwon, Jeahoo; Lu, Kun Ping; Nicholson, Linda K

    2016-12-01

    The peptidyl prolyl isomerase Pin1 has two domains that are considered to be its binding (WW) and catalytic (PPIase) domains, both of which interact with phosphorylated Ser/Thr-Pro motifs. This shared specificity might influence substrate selection, as many known Pin1 substrates have multiple sequentially close phosphoSer/Thr-Pro motifs, including the protein interleukin-1 receptor-associated kinase-1 (IRAK1). The IRAK1 undefined domain (UD) contains two sets of such neighboring motifs (Ser131/Ser144 and Ser163/Ser173), suggesting possible bivalent interactions with Pin1. Using a series of NMR titrations with 15N-labeled full-length Pin1 (Pin1-FL), PPIase, or WW domain and phosphopeptides representing the Ser131/Ser144 and Ser163/Ser173 regions of IRAK1-UD, bivalent interactions were investigated. Binding studies using singly phosphorylated peptides showed that individual motifs displayed weak affinities (> 100 μm) for Pin1-FL and each isolated domain. Analysis of dually phosphorylated peptides binding to Pin1-FL showed that inclusion of bivalent states was necessary to fit the data. The resulting complex model and fitted parameters were applied to predict the impact of bivalent states at low micromolar concentrations, demonstrating significant affinity enhancement for both dually phosphorylated peptides (3.5 and 24 μm for peptides based on the Ser131/Ser144 and Ser163/Ser173 regions, respectively). The complementary technique biolayer interferometry confirmed the predicted affinity enhancement for a representative set of singly and dually phosphorylated Ser131/Ser144 peptides at low micromolar concentrations, validating model predictions. These studies provide novel insights regarding the complexity of interactions between Pin1 and activated IRAK1, and more broadly suggest that phosphorylation of neighboring Ser/Thr-Pro motifs in proteins might provide competitive advantage at cellular concentrations for engaging with Pin1. © 2016 Federation of European

  8. Physikalische Grundlagen von chemischen Raman-Sensoren mit Schwerpunkt auf faseroptischen SERS-Sonden

    OpenAIRE

    Viets, Carmen

    2001-01-01

    Faseroptische SERS-Sensoren wurden durch die Beschichtung der Endflächen von optischen Fasern mit rauhen Metallfilmen erzeugt. Zu den verschiedenen Präparationstechniken, die angewendet und verglichen wurden, gehörten das langsame Aufdampfen von Metall-Inselfilmen und das Bedampfen von Nanopartikeln, aufgerauhten oder elektronenlithographisch strukturierten Oberflächen mit Metallfilmen. Der Einfluß der Laserleistung auf die Messungen mit SERS-Sensoren wurde untersucht, und es wurden maximale ...

  9. CisSERS: Customizable In Silico Sequence Evaluation for Restriction Sites.

    Directory of Open Access Journals (Sweden)

    Richard M Sharpe

    Full Text Available High-throughput sequencing continues to produce an immense volume of information that is processed and assembled into mature sequence data. Data analysis tools are urgently needed that leverage the embedded DNA sequence polymorphisms and consequent changes to restriction sites or sequence motifs in a high-throughput manner to enable biological experimentation. CisSERS was developed as a standalone open source tool to analyze sequence datasets and provide biologists with individual or comparative genome organization information in terms of presence and frequency of patterns or motifs such as restriction enzymes. Predicted agarose gel visualization of the custom analyses results was also integrated to enhance the usefulness of the software. CisSERS offers several novel functionalities, such as handling of large and multiple datasets in parallel, multiple restriction enzyme site detection and custom motif detection features, which are seamlessly integrated with real time agarose gel visualization. Using a simple fasta-formatted file as input, CisSERS utilizes the REBASE enzyme database. Results from CisSERS enable the user to make decisions for designing genotyping by sequencing experiments, reduced representation sequencing, 3'UTR sequencing, and cleaved amplified polymorphic sequence (CAPS molecular markers for large sample sets. CisSERS is a java based graphical user interface built around a perl backbone. Several of the applications of CisSERS including CAPS molecular marker development were successfully validated using wet-lab experimentation. Here, we present the tool CisSERS and results from in-silico and corresponding wet-lab analyses demonstrating that CisSERS is a technology platform solution that facilitates efficient data utilization in genomics and genetics studies.

  10. CisSERS: Customizable In Silico Sequence Evaluation for Restriction Sites.

    Science.gov (United States)

    Sharpe, Richard M; Koepke, Tyson; Harper, Artemus; Grimes, John; Galli, Marco; Satoh-Cruz, Mio; Kalyanaraman, Ananth; Evans, Katherine; Kramer, David; Dhingra, Amit

    2016-01-01

    High-throughput sequencing continues to produce an immense volume of information that is processed and assembled into mature sequence data. Data analysis tools are urgently needed that leverage the embedded DNA sequence polymorphisms and consequent changes to restriction sites or sequence motifs in a high-throughput manner to enable biological experimentation. CisSERS was developed as a standalone open source tool to analyze sequence datasets and provide biologists with individual or comparative genome organization information in terms of presence and frequency of patterns or motifs such as restriction enzymes. Predicted agarose gel visualization of the custom analyses results was also integrated to enhance the usefulness of the software. CisSERS offers several novel functionalities, such as handling of large and multiple datasets in parallel, multiple restriction enzyme site detection and custom motif detection features, which are seamlessly integrated with real time agarose gel visualization. Using a simple fasta-formatted file as input, CisSERS utilizes the REBASE enzyme database. Results from CisSERS enable the user to make decisions for designing genotyping by sequencing experiments, reduced representation sequencing, 3'UTR sequencing, and cleaved amplified polymorphic sequence (CAPS) molecular markers for large sample sets. CisSERS is a java based graphical user interface built around a perl backbone. Several of the applications of CisSERS including CAPS molecular marker development were successfully validated using wet-lab experimentation. Here, we present the tool CisSERS and results from in-silico and corresponding wet-lab analyses demonstrating that CisSERS is a technology platform solution that facilitates efficient data utilization in genomics and genetics studies.

  11. Non-labeling multiplex surface enhanced Raman scattering (SERS) detection of volatile organic compounds (VOCs)

    DEFF Research Database (Denmark)

    Wong, Chi Lok; Dinish, U. S.; Schmidt, Michael Stenbæk

    2014-01-01

    chemical sensing layer for the enrichment of gas molecules on sensor surface. The leaning nano-pillar substrate also showed highly reproducible SERS signal in cyclic VOCs detection, which can reduce the detection cost in practical applications. Further, multiplex SERS detection on different combination...... device for multiplex, specific and highly sensitive detection of complex VOCs samples that can find potential applications in exhaled breath analysis, hazardous gas analysis, homeland security and environmental monitoring....

  12. Fabrication of Semiconductor ZnO Nanostructures for Versatile SERS Application

    Directory of Open Access Journals (Sweden)

    Lili Yang

    2017-11-01

    Full Text Available Since the initial discovery of surface-enhanced Raman scattering (SERS in the 1970s, it has exhibited a huge potential application in many fields due to its outstanding advantages. Since the ultra-sensitive noble metallic nanostructures have increasingly exposed themselves as having some problems during application, semiconductors have been gradually exploited as one of the critical SERS substrate materials due to their distinctive advantages when compared with noble metals. ZnO is one of the most representative metallic oxide semiconductors with an abundant reserve, various and cost-effective fabrication techniques, as well as special physical and chemical properties. Thanks to the varied morphologies, size-dependent exciton, good chemical stability, a tunable band gap, carrier concentration, and stoichiometry, ZnO nanostructures have the potential to be exploited as SERS substrates. Moreover, other distinctive properties possessed by ZnO such as biocompatibility, photocatcalysis and self-cleaning, and gas- and chemo-sensitivity can be synergistically integrated and exerted with SERS activity to realize the multifunctional potential of ZnO substrates. In this review, we discuss the inevitable development trend of exploiting the potential semiconductor ZnO as a SERS substrate. After clarifying the root cause of the great disparity between the enhancement factor (EF of noble metals and that of ZnO nanostructures, two specific methods are put forward to improve the SERS activity of ZnO, namely: elemental doping and combination of ZnO with noble metals. Then, we introduce a distinctive advantage of ZnO as SERS substrate and illustrate the necessity of reporting a meaningful average EF. We also summarize some fabrication methods for ZnO nanostructures with varied dimensions (0–3 dimensions. Finally, we present an overview of ZnO nanostructures for the versatile SERS application.

  13. Analysis of silver nanoparticles in antimicrobial products using surface-enhanced Raman spectroscopy (SERS).

    Science.gov (United States)

    Guo, Huiyuan; Zhang, Zhiyun; Xing, Baoshan; Mukherjee, Arnab; Musante, Craig; White, Jason C; He, Lili

    2015-04-07

    Silver nanoparticles (AgNPs) are the most commonly used nanoparticles in consumer products. Concerns over human exposure to and risk from these particles have resulted in increased interest in novel strategies to detect AgNPs. This study investigated the feasibility of surface-enhanced Raman spectroscopy (SERS) as a method for the detection and quantification of AgNPs in antimicrobial products. By using ferbam (ferric dimethyl-dithiocarbamate) as an indicator molecule that binds strongly onto the nanoparticles, AgNPs detection and discrimination were achieved based on the signature SERS response of AgNPs-ferbam complexes. SERS response with ferbam was distinct for silver ions, silver chloride, silver bulk particles, and AgNPs. Two types of AgNPs with different coatings, citrate and polyvinylpirrolidone (PVP), both showed strong interactions with ferbam and induced strong SERS signals. SERS was effectively applicable for detecting Ag particles ranging from 20 to 200 nm, with the highest signal intensity in the 60-100 nm range. A linear relationship (R(2) = 0.9804) between Raman intensity and citrate-AgNPs concentrations (60 nm; 0-20 mg/L) indicates the potential for particle quantification. We also evaluated SERS detection of AgNPs in four commercially available antimicrobial products. Combined with ICP-MS and TEM data, the results indicated that the SERS response is primarily dependent on size, but also affected by AgNPs concentration. The findings demonstrate that SERS is a promising analytical platform for studying environmentally relevant levels of AgNPs in consumer products and related matrices.

  14. [Study on the ingredients of reserpine by TLC-FT-SERS].

    Science.gov (United States)

    Wang, Y; Zi, F; Wang, Y; Zhao, Y; Zhang, X; Weng, S

    1999-12-01

    A new method for analysing the ingredients of reserpine by thin layer chromatography (TLC) and surface-enhanced Raman spectroscopy (SERS) is reported in this paper. The results show that the characteristic spectral bands of reserpine satuated at the thin layer with the amount of sample about 2 microg were obtained. The difference between SERS and solid spectra was found. An absorption model of reserpine and silver sol was proposed. This method can be used to analyse the chemical ingredients with high sensitivity.

  15. INTRODUCTION OF PASTEURIZED/RAW COW'S MILK DURING THE SECOND SEMESTER OF LIFE AS A RISK FACTOR OF TYPE 1 DIABETES MELLITUS IN SCHOOL CHILDREN AND ADOLESCENTS.

    Science.gov (United States)

    Villagrán-García, Edna F; Hurtado-López, Erika F; Vasquez-Garibay, Edgar M; Troyo-Sanromán, Rogelio; Aguirre-Salas, Liuba M; Larrosa-Haro, Alfredo; León-Robles, Ruth V

    2015-08-01

    to demonstrate that type 1 diabetes mellitus (T1DM) in school children and adolescents is associated with the early introduction of pasteurized/raw cow's milk in the second semester of life. this non-probabilistic study included 150 subjects (75 patients and 75 controls), divided according to sex and age (range, 6 to 16 years). T1DM was considered to be a dependent variable, and pasteurized/ raw cow's milk (P/RCM) was considered to be an independent variable in the study. The statistical analyses included chi-squared test, odds ratio and 95% confidence intervals. the subjects were 51% male, age 11 ± 3.2 years, and 80% were breastfed, 18% were exclusively breastfed, and 13% received pasteurized/raw cow's milk. The children receiving P/RCM had a higher risk of T1DM [OR, 3.9 (1.2-12.8)]. The presence of T1DM was three times higher in those consuming P/RCM vs. those receiving follow-up formula [RM, 3.2 (1.03-10.07)]. introducing pasteurized/raw cow's milk in the second semester of life increased by four times the likelihood of developing T1DM in children and adolescents. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  16. Dealing with complex and ill-structured problems: results of a Plan-Do-Check-Act experiment in a business engineering semester

    Science.gov (United States)

    Riis, Jens Ove; Achenbach, Marlies; Israelsen, Poul; Kyvsgaard Hansen, Poul; Johansen, John; Deuse, Jochen

    2017-07-01

    Challenged by increased globalisation and fast technological development, we carried out an experiment in the third semester of a global business engineering programme aimed at identifying conditions for training student in dealing with complex and ill-structured problems of forming a new business. As this includes a fuzzy front end, learning cannot be measured in traditional, quantitative terms; therefore, we have explored the use of reflection to convert tacit knowledge to explicit knowledge. The experiment adopted a Plan-Do-Check-Act approach and concluded with developing a plan for new learning initiatives in the subsequent year's semester. The findings conclude that (1) problem-based learning develops more competencies than ordinarily measured at the examination, especially, the social/communication and personal competencies are developed; (2) students are capable of dealing with a complex and ambiguous problem, if properly guided. Four conditions were identified; (3) most students are not conscious of their learning, but are able to reflect if properly encouraged; and (4) improving engineering education should be considered as an organisational learning process.

  17. EFEKTIVITAS MODEL PROBLEM BASED LEARNING BERBANTUAN MEDIA AUDIO VISUAL DITINJAU DARI HASIL BELAJAR IPA SISWA KELAS 5 SDN 1 GADU SAMBONG - BLORA SEMESTER 2 TAHUN 2014/2015

    Directory of Open Access Journals (Sweden)

    Andhini Virgiana

    2016-05-01

    Full Text Available Tujuan dari penelitian ini adalah untuk mengetahui perbedaan tingkat hasil belajar antara model problem based learning berbantuan media audio visual dengan model pembelajaran think pair share berbantuan media visual pada pembelajaran IPA siswa kelas 5 SDN 1 Gadu Sambong Kabupaten Blora semester 2 tahun pelajaran 2014/2015. Penelitian ini merupakan penelitian quasi experiment dengan nonequivalent control group design. Subjek penelitian dalam penelitian ini adalah siswa kelas 5 SDN 1 Gadu dan siswa kelas 5 SDN 2 Gagakan. Teknik  pengumpulan data dalam penelitian adalah tes dan observasi. Teknik analisis data yang digunakan adalah statistik deskriptif, statistik parametrik, dan uji t dengan  independent sample t-tes pada taraf signifikansi 5% (α = 0,05. Berdasarkan hasil penelitian dan pembahasan, maka dapat disimpulkan bahwa terdapat perbedaan tingkat efektivitas antara model problem based learning berbantu media audio visual dengan model pembelajaran think pair share berbantu media visual terhadap hasil belajar IPA siswa kelas 5 SDN 1 Gadu Kecamatan Sambong Kabupaten Blora semester 2 tahun 2014/2015. Terbukti hal ini ditunjukkan oleh hasil uji t-test sebesar 3,603 > 1,999 dan signifikansi sebesar 0,001 rata-rata kelas kontrol yaitu 87,0588 > 80,2000.

  18. Razón y ser de los tipos

    Directory of Open Access Journals (Sweden)

    González Blanco, F.

    2006-09-01

    Full Text Available Fisac’s oeuvre has traditionally been defined in terms of its individualism, its non-association with any school or movement whatsoever. A deeper analysis of one of his best known lines of research, the hollow forms of prestressed concrete (his famous “bones”, reveals a host of engineers, practitioners and businessmen united around a common core of friendship and ingenuity whose work crystallized in an evolutionary process interesting in its own right.This text is, therefore, a tribute not only to Miguel Fisac, but to all those who participated in this story, which lasted a mere ten years (the nineteen sixties: a story of risk, success and failure, where the architect often stood in solitude in the midst of a densely populated circle of engineers, quantity surveyors, contractors and inventors.Tradicionalmente se ha destacado de Fisac su carácter individualista, no atado a escuela o movimiento alguno. Profundizando en una de sus líneas investigadoras más conocidas como son las formas huecas de hormigón pretensado, sus famosos “huesos”, es inmediato encontrarse con una nube de técnicos, prácticos o empresarios unidos por un hilo común de amistad e ingenio, cuyo trabajo conjunto cristalizó en un proceso evolutivo ya de por sí interesante.Es por ello extensible este texto homenaje no sólo a la figura de Miguel Fisac, sino a todos aquellos que en el corto periodo de una década (los años sesenta participaron de esta historia. Una historia de riesgos, de aciertos y de errores, donde la figura del arquitecto queda en muchas ocasiones aislada entre la densidad de ingenieros, aparejadores, constructores o inventores.

  19. Modification of the SERS spectrum of cyanide traces due to complex formation between cyanide and silver

    Science.gov (United States)

    Cao Dao, Tran; Kieu, Ngoc Minh; Quynh Ngan Luong, Truc; Cao, Tuan Anh; Hai Nguyen, Ngoc; Le, Van Vu

    2018-06-01

    It is well known that cyanide is an extremely toxic lethal poison with human death within minutes after exposure to only 300 ppm cyanide. On the other hand, cyanide is released into the environment (mainly through waste water) every day from various human activities. Therefore, rapid, sensitive and cost-effective cyanide trace detection is an urgent need. Surface-enhanced Raman scattering (SERS) is a method that meets these requirements. It should be noted, however, that in this technique SERS substrates, which are usually made of gold or silver, will be leached with aqueous cyanide by the formation of complexes between gold or silver with cyanide. This will cause the SERS spectrum of cyanide to be modified. When determining cyanide concentrations by SERS analysis, this spectral modification should be taken into account. This report presents the SERS spectral modification of aqueous cyanide traces (in ppm and lower concentration range) when the SERS substrates used are flower-like silver micro-structures.

  20. A practicable detection system for genetically modified rice by SERS-barcoded nanosensors.

    Science.gov (United States)

    Chen, Kun; Han, Heyou; Luo, Zhihui; Wang, Yanjun; Wang, Xiuping

    2012-04-15

    Since the global cultivation of genetically modified crops constantly expands, it remains a high demand to establish different ways to sort food and feed that consist or contain genetically modified organisms. Surface-enhanced Raman scattering (SERS) spectroscopy is a flexible tool for biological analysis due to its excellent properties for detecting wide varieties of target biomolecules including nucleic acids. In the present study, a SERS-barcoded nanosensor was developed to detect Bacillus thuringiensis (Bt) gene-transformed rice expressing insecticidal proteins. The barcoded sensor was designed by encapsulation of gold nanoparticles with silica and conjugation of oligonucleotide strands for targeting DNA strands. The transition between the cry1A(b) and cry1A(c) fusion gene sequence was used to construct a specific SERS-based detection method with a detection limit of 0.1 pg/mL. In order to build the determination models to screen transgene, a series mixture of Bt rice and normal rice were prepared for SERS assay, and the limit of detection was 0.1% (w/w) transgenic Bt rice relative to normal rice. The sensitivity and accuracy of the SERS-based assay was comparable with real-time PCR. The SERS-barcoded analytical method would provide precise detection of transgenic rice varieties but also informative supplement to avoid false positive outcomes. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  1. Surface enhanced Raman spectroscopy (SERS) for in vitro diagnostic testing at the point of care

    Science.gov (United States)

    Marks, Haley; Schechinger, Monika; Garza, Javier; Locke, Andrea; Coté, Gerard

    2017-06-01

    Point-of-care (POC) device development is a growing field that aims to develop low-cost, rapid, sensitive in-vitro diagnostic testing platforms that are portable, self-contained, and can be used anywhere - from modern clinics to remote and low resource areas. In this review, surface enhanced Raman spectroscopy (SERS) is discussed as a solution to facilitating the translation of bioanalytical sensing to the POC. The potential for SERS to meet the widely accepted "ASSURED" (Affordable, Sensitive, Specific, User-friendly, Rapid, Equipment-free, and Deliverable) criterion provided by the World Health Organization is discussed based on recent advances in SERS in vitro assay development. As SERS provides attractive characteristics for multiplexed sensing at low concentration limits with a high degree of specificity, it holds great promise for enhancing current efforts in rapid diagnostic testing. In outlining the progression of SERS techniques over the past years combined with recent developments in smart nanomaterials, high-throughput microfluidics, and low-cost paper diagnostics, an extensive number of new possibilities show potential for translating SERS biosensors to the POC.

  2. Aluminum nanostructures with strong visible-range SERS activity for versatile micropatterning of molecular security labels.

    Science.gov (United States)

    Lay, Chee Leng; Koh, Charlynn Sher Lin; Wang, Jing; Lee, Yih Hong; Jiang, Ruibin; Yang, Yijie; Yang, Zhe; Phang, In Yee; Ling, Xing Yi

    2018-01-03

    The application of aluminum (Al)-based nanostructures for visible-range plasmonics, especially for surface-enhanced Raman scattering (SERS), currently suffers from inconsistent local electromagnetic field distributions and/or inhomogeneous distribution of probe molecules. Herein, we lithographically fabricate structurally uniform Al nanostructures which enable homogeneous adsorption of various probe molecules. Individual Al nanostructures exhibit strong local electromagnetic field enhancements, in turn leading to intense SERS activity. The average SERS enhancement factor (EF) for individual nanostructures exceeds 10 4 for non-resonant probe molecules in the visible spectrum. These Al nanostructures also retain more than 70% of their original SERS intensities after one-month storage, displaying superb stability under ambient conditions. We further achieve tunable polarization-dependent SERS responses using anisotropic Al nanostructures, facilitating the design of sophisticated SERS-based security labels. Our micron-sized security label comprises two-tier security features, including a machine-readable hybrid quick-response (QR) code overlaid with a set of ciphertexts. Our work demonstrates the versatility of Al-based structures in low-cost modern chemical nano-analytics and forgery protection.

  3. Colorimetry and SERS dual-mode detection of telomerase activity: combining rapid screening with high sensitivity.

    Science.gov (United States)

    Zong, Shenfei; Wang, Zhuyuan; Chen, Hui; Hu, Guohua; Liu, Min; Chen, Peng; Cui, Yiping

    2014-01-01

    As an important biomarker and therapeutic target, telomerase has attracted considerable attention concerning its detection and monitoring. Here, we present a colorimetry and surface enhanced Raman scattering (SERS) dual-mode telomerase activity detection method, which has several distinctive advantages. First, colorimetric functionality allows rapid preliminary discrimination of telomerase activity by the naked eye. Second, the employment of SERS technique results in greatly improved detection sensitivity. Third, the combination of colorimetry and SERS into one detection system can ensure highly efficacious and sensitive screening of numerous samples. Besides, the avoidance of polymerase chain reaction (PCR) procedures further guarantees fine reliability and simplicity. Generally, the presented method is realized by an "elongate and capture" procedure. To be specific, gold nanoparticles modified with Raman molecules and telomeric repeat complementary oligonucleotide are employed as the colorimetric-SERS bifunctional reporting nanotag, while magnetic nanoparticles functionalized with telomerase substrate oligonucleotide are used as the capturing substrate. Telomerase can synthesize and elongate telomeric repeats onto the capturing substrate. The elongated telomeric repeats subsequently facilitate capturing of the reporting nanotag via hybridization between telomeric repeat and its complementary strand. The captured nanotags can cause a significant difference in the color and SERS intensity of the magnetically separated sediments. Thus both the color and SERS can be used as indicators of the telomerase activity. With fast screening ability and outstanding sensitivity, we anticipate that this method would greatly promote practical application of telomerase-based early-stage cancer diagnosis.

  4. Label-free SERS in biological and biomedical applications: Recent progress, current challenges and opportunities

    Science.gov (United States)

    Zheng, Xiao-Shan; Jahn, Izabella Jolan; Weber, Karina; Cialla-May, Dana; Popp, Jürgen

    2018-05-01

    To achieve an insightful look within biomolecular processes on the cellular level, the development of diseases as well as the reliable detection of metabolites and pathogens, a modern analytical tool is needed that is highly sensitive, molecular-specific and exhibits fast detection. Surface-enhanced Raman spectroscopy (SERS) is known to meet these requirements and, within this review article, the recent progress of label-free SERS in biological and biomedical applications is summarized and discussed. This includes the detection of biomolecules such as metabolites, nucleic acids and proteins. Further, the characterization and identification of microorganisms has been achieved by label-free SERS-based approaches. Eukaryotic cells can be characterized by SERS in order to gain information about the outer cell wall or to detect intracellular molecules and metabolites. The potential of SERS for medically relevant detection schemes is emphasized by the label-free detection of tissue, the investigation of body fluids as well as applications for therapeutic and illicit drug monitoring. The review article is concluded with an evaluation of the recent progress and current challenges in order to highlight the direction of label-free SERS in the future.

  5. Surface enhanced Raman spectroscopy (SERS for in vitro diagnostic testing at the point of care

    Directory of Open Access Journals (Sweden)

    Marks Haley

    2017-06-01

    Full Text Available Point-of-care (POC device development is a growing field that aims to develop low-cost, rapid, sensitive in-vitro diagnostic testing platforms that are portable, self-contained, and can be used anywhere – from modern clinics to remote and low resource areas. In this review, surface enhanced Raman spectroscopy (SERS is discussed as a solution to facilitating the translation of bioanalytical sensing to the POC. The potential for SERS to meet the widely accepted “ASSURED” (Affordable, Sensitive, Specific, User-friendly, Rapid, Equipment-free, and Deliverable criterion provided by the World Health Organization is discussed based on recent advances in SERS in vitro assay development. As SERS provides attractive characteristics for multiplexed sensing at low concentration limits with a high degree of specificity, it holds great promise for enhancing current efforts in rapid diagnostic testing. In outlining the progression of SERS techniques over the past years combined with recent developments in smart nanomaterials, high-throughput microfluidics, and low-cost paper diagnostics, an extensive number of new possibilities show potential for translating SERS biosensors to the POC.

  6. Biofabrication of chitosan-silver composite SERS substrates enabling quantification of adenine by a spectroscopic shift

    International Nuclear Information System (INIS)

    Luo, X L; Bentley, W E; Buckhout-White, S; Rubloff, G W

    2011-01-01

    Surface-enhanced Raman scattering (SERS) has grown dramatically as an analytical tool for the sensitive and selective detection of molecules adsorbed on nano-roughened noble metal structures. Quantification with SERS based on signal intensity remains challenging due to the complicated fabrication process to obtain well-dispersed nanoparticles and well-ordered substrates. We report a new biofabrication strategy of SERS substrates that enable quantification through a newly discovered spectroscopic shift resulting from the chitosan-analyte interactions in solution. We demonstrate this phenomenon by the quantification of adenine, which is an essential part of the nucleic acid structure and a key component in pathways which generate signal molecules for bacterial communications. The SERS substrates were fabricated simply by sequential electrodeposition of chitosan on patterned gold electrodes and electroplating of a silver nitrate solution through the chitosan scaffold to form a chitosan-silver nanoparticle composite. Active SERS signals of adenine solutions were obtained in real time from the chitosan-silver composite substrates with a significant concentration-dependent spectroscopic shift. The Lorentzian curve fitting of the dominant peaks suggests the presence of two separate peaks with a concentration-dependent area percentage of the separated peaks. The chitosan-mediated composite SERS substrates can be easily biofabricated on predefined electrodes within microfluidic channels for real-time detection in microsystems.

  7. Designing multilayered nanoplatforms for SERS-based detection of genetically modified organisms

    Science.gov (United States)

    Uluok, Saadet; Guven, Burcu; Eksi, Haslet; Ustundag, Zafer; Tamer, Ugur; Boyaci, Ismail Hakki

    2015-01-01

    In this study, the multilayered surface-enhanced Raman spectroscopy (SERS) platforms were developed for the analysis of genetically modified organisms (GMOs). For this purpose, two molecules [11-mercaptoundecanoic acid (11-MUA) and 2-mercaptoethylamine (2-MEA)] were attached with Aurod and Auspherical nanoparticles to form multilayered constructions on the gold (Au)slide surface. The best multilayered platform structure was chosen depending on SERS enhancement, and this surface was characterised with atomic force microscopy (AFM) and attenuated total reflectance Fourier transform infrared spectroscopy. After the optimum multilayered SERS platform and nanoparticle interaction was identified, the oligonucleotides on the Aurod nanoparticles and Auslide were combined to determine target concentrations from the 5,5'-dithiobis (2-nitrobenzoic acid) (DTNB) signals using SERS. The correlation between the SERS intensities for DTNB and target concentrations was found to be linear within a range of 10 pM to 1 µM, and with a detection limit of 34 fM. The selectivity and specificity of the developed sandwich assay were tested using negative and positive controls, and nonsense and real sample studies. The obtained results showed that the multilayered SERS sandwich method allows for sensitive, selective, and specific detection of oligonucleotide sequences.

  8. Chemically Roughened Solid Silver: A Simple, Robust and Broadband SERS Substrate

    Directory of Open Access Journals (Sweden)

    Shavini Wijesuriya

    2016-10-01

    Full Text Available Surface-enhanced Raman spectroscopy (SERS substrates manufactured using complex nano-patterning techniques have become the norm. However, their cost of manufacture makes them unaffordable to incorporate into most biosensors. The technique shown in this paper is low-cost, reliable and highly sensitive. Chemical etching of solid Ag metal was used to produce simple, yet robust SERS substrates with broadband characteristics. Etching with ammonium hydroxide (NH4OH and nitric acid (HNO3 helped obtain roughened Ag SERS substrates. Scanning electron microscopy (SEM and interferometry were used to visualize and quantify surface roughness. Flattened Ag wires had inherent, but non-uniform roughness having peaks and valleys in the microscale. NH4OH treatment removed dirt and smoothened the surface, while HNO3 treatment produced a flake-like morphology with visibly more surface roughness features on Ag metal. SERS efficacy was tested using 4-methylbenzenethiol (MBT. The best SERS enhancement for 1 mM MBT was observed for Ag metal etched for 30 s in NH4OH followed by 10 s in HNO3. Further, MBT could be quantified with detection limits of 1 pM and 100 µM, respectively, using 514 nm and 1064 nm Raman spectrometers. Thus, a rapid and less energy intensive method for producing solid Ag SERS substrate and its efficacy in analyte sensing was demonstrated.

  9. Combining Project-Based Learning and Community-Based Research in a Research Methodology Course: The Lessons Learned

    Science.gov (United States)

    Arantes do Amaral, João Alberto; Lino dos Santos, Rebeca Júlia Rodrigues

    2018-01-01

    In this article, we present our findings regarding the course "Research Methodology," offered to 22 first-year undergraduate students studying Administration at the Federal University of São Paulo, Osasco, Brazil. The course, which combined community-based research and project-based learning, was developed during the second semester of…

  10. Intracellular surface-enhanced Raman scattering (SERS) with thermally stable gold nanoflowers grown from Pt and Pd seeds

    KAUST Repository

    Song, Hyon Min; Deng, Lin; Khashab, Niveen M.

    2013-01-01

    SERS provides great sensitivity at low concentrations of analytes. SERS combined with near infrared (NIR)-resonant gold nanomaterials are important candidates for theranostic agents due to their combined extinction properties and sensing abilities

  11. A Case Study of Teaching Marketing Research Using Client-Sponsored Projects: Method, Challenges, and Benefits

    Science.gov (United States)

    Bove, Liliana L.; Davies, W. Martin

    2009-01-01

    This case study outlines the use of client-sponsored research projects in a quantitative postgraduate marketing research subject conducted in a 12-week semester in a research-intensive Australian university. The case study attempts to address the dearth of recent literature on client-sponsored research projects in the discipline of marketing.…

  12. Association of the hOGG1 Ser326Cys polymorphism with sporadic amyotrophic lateral sclerosis.

    Science.gov (United States)

    Coppedè, Fabio; Mancuso, Michelangelo; Lo Gerfo, Annalisa; Carlesi, Cecilia; Piazza, Selina; Rocchi, Anna; Petrozzi, Lucia; Nesti, Claudia; Micheli, Dario; Bacci, Andrea; Migliore, Lucia; Murri, Luigi; Siciliano, Gabriele

    2007-06-13

    Amyotropic lateral sclerosis (ALS) is a fatal and progressive neurodegenerative disease causing the loss of motoneurons of the brain and the spinal cord. The etiology of ALS is still uncertain, but males are at increased risk for the disease than females. Several studies have suggested that motoneurons in ALS might be subjected to the double insult of increased DNA oxidative damage and deficiencies in DNA repair systems. Particularly, increased levels of 8-oxoguanine and impairments of the DNA base excision repair system have been observed in neurons of ALS patients. There is evidence that the Ser326Cys polymorphism of the human 8-oxoguanine DNA glycosylase 1 (hOGG1) gene is associated with a reduced DNA repair activity. To evaluate the role of the hOGG1 Ser326Cys polymorphism in sporadic ALS (sALS), we screened 136 patients and 129 matched controls. In the total population, we observed association between both the Cys326 allele (p=0.02) and the combined Ser326Cys+Cys326Cys genotype (OR=1.65, 95% CI=1.06-2.88) and increased risk of disease. After stratification by gender, the Cys326 allele (p=0.01), both the Ser326Cys genotype (OR=2.14, 95% CI=1.09-4.19) and the combined Ser326Cys+Cys326Cys genotype (OR=2.15, 95% CI=1.16-4.01) were associated with sALS risk only in males. No significant association between the Ser326Cys polymorphism and disease phenotype, including age and site of onset and disease progression, was observed. Present results suggest a possible involvement of the hOGG1 Ser326Cys polymorphism in sALS pathogenesis.

  13. The Correlation Between Students’Vocabulary Mastery and Their Interest in English Toward Reading Comprehension in descriptive Text at the Second Semester of Muhammadiyah University of Metro Academic Year 2014/2015

    Directory of Open Access Journals (Sweden)

    Eva Faliyanti

    2015-04-01

    Full Text Available Abstarct -------------------------------------------------------------------------------------------------------------------- Vocabulary is one aspects  in reading comprehension. By having  a lot vocabulary, the students understand in reading comprehension. The interest in English also gives effect of students mastery in English. Before the students start to read they are must be interested in English first. Reading is one of skills in English that very essential for the students, because by reading the students can get information from the text. In this research the researcher focoses on reading comprehension in descriptive text. The problems formulation in this research are; (1 How far is the students score of ability in vocabulary mastery toward reading comprehension in descriptive text? (2 How far is the students score of ability in students interest in English toward reading comprehension in descriptive text? (3 How far is the correlation between students’ score of vocabulary mastery and students interest in English toward reading comprehension in descriptive text?. The objective of the research are; (1 To identify the students’ score in vocabulary mastery toward reading comprehension in descriptive text. (2 To identify the students’ score in students interest in English toward reading comprehension in descriptive text. (3 To find out how far the correlation between students’ score of vocabulary mastery and students interest in English toward reading compregension in descritive text. The research was conducted at the second semester of Muhammadiyah University Students in Academic Year 2014/2015. The population of this research was 127 students. The researcher used cluster ramdom sampling in taking sample. In collecting the data the researcher used test and questionnarie, namely vocabulary mastery and reading comprehension in descriptive text. In questionnarie used to students interest in English and in analyzing the data, the

  14. Preparing Chemistry Majors for the 21st Century through a Comprehensive One-Semester Course Focused on Professional Preparation, Contemporary Issues, Scientific Communication, and Research Skills

    Science.gov (United States)

    Marteel-Parrish, Anne E.; Lipchock, James M.

    2018-01-01

    Success in chemistry in the 21st century requires not only a mastery of important chemical concepts, but also the skills to apply this knowledge to important societal issues and the ability to effectively convey scientific information using a range of media. In response to this challenge we have developed an innovative four-credit seminar that…

  15. Safety, Tolerability, and Antihypertensive Effect of SER100, an Opiate Receptor-Like 1 (ORL-1) Partial Agonist, in Patients With Isolated Systolic Hypertension.

    Science.gov (United States)

    Kantola, Ilkka; Scheinin, Mika; Gulbrandsen, Trygve; Meland, Nils; Smerud, Knut T

    2017-11-01

    The purpose of the present trial was to evaluate safety, tolerability, and effect on systolic blood pressure (SBP) of SER100 in a small group of patients with isolated systolic hypertension (ISH) in treatment with at least 1 antihypertensive drug. Eligible patients were randomized to either SER100 (10 mg) or placebo in a crossover design, and 2 doses were given subcutaneously (SC), 8 hours apart, on 2 consecutive days. On all treatment days patients were monitored with an ambulatory blood pressure measurement device for 12 daytime hours. Seventeen patients completed treatment. There were no serious or severe adverse events. Relative to placebo SER100 induced an average reduction of SBP during the 2 treatment days of 7.0 mm Hg (P = 0.0032), whereas the average reduction of diastolic blood pressure (DBP) over the same period was 3.8 mm Hg (P = 0.0011). For patients with ISH, this short-term cross-over study of SC SER100 demonstrated an acceptable safety profile and consistent, significant lowering of SBP and DBP. As initial clinical proof of concept for a new class of drugs, a nociceptin agonist peptide, the results were encouraging and warrant further research. © 2016, The American College of Clinical Pharmacology.

  16. PENERAPAN KOSAKATA DALAM MENULIS NASKAH PIDATO MAHASISWA SEMESTER IV PRODI PENDIDIKAN BAHASA DAN SASTRA INDONESIA STKIP MPL

    Directory of Open Access Journals (Sweden)

    Lisdwiana Kurniati

    2016-09-01

    Full Text Available The difficulties in speech text writing were faced by the students. They were confused inwriting the text creatively. It was indicated from the students less vocabulary then madethe students less writing. Students’ vocabularies such as synonym, antonym, andlanguage style were improving students’ skill in speech text writing. Through thosevocabularies, the students could choose and use it, then got good quality in writing.This research was reviewing vocabularies implementation in speech text writing. Theobjective of this research was students’ vocabularies in language skill activity throughspeech text writing.Key Words: speech text writing, vocabularies, language style

  17. Trace determination of thiram using SERS-active hollow sea-urchin gold nanoparticles

    International Nuclear Information System (INIS)

    Zhang, Guanghui; Zhang, Chuankun; Ma, Yanan; Wang, Zheng; Wang, Shun; Xu, Chan; Wang, Dashuang

    2017-01-01

    Surface-enhanced Raman scattering (SERS) is greatly structure-dependent on the absorbed nanoparticles. Nanostructures with different novel morphologies show different Raman enhancement factor orders of magnitude. Herein, a unique nanostructure with fruitful SERS-active sites, composed of hollow interiors and thorns which named as hollow sea-urchin gold nanoparticles (HSU-GNPs), was synthesized by using a one-pot galvanic replacement method. And the corresponding morphologies and optical properties were characterized by TEM images and absorption spectra. Importantly, the synthetic parameters of HSU-GNPs were optimized to obtain a superior SERS performance by analyzing the formation mechanism and the SERS spectra of R6G-labeled HSU-GNPs which obtained at different concentrations of AgNO_3. Furthermore, the SERS-based application of HSU-GNPs was performed on the dose-response detection of thiram. The experimental result shows this detection strategy is available for thiram with decent sensitivity and reproducibility, which suggests that it is an excellent candidate for the detection of pesticides.

  18. Commercial Gold Nanoparticles on Untreated Aluminum Foil: Versatile, Sensitive, and Cost-Effective SERS Substrate

    Directory of Open Access Journals (Sweden)

    Kristina Gudun

    2017-01-01

    Full Text Available We introduce low-cost, tunable, hybrid SERS substrate of commercial gold nanoparticles on untreated aluminum foil (AuNPs@AlF. Two or three AuNP centrifugation/resuspension cycles are proven to be critical in the assay preparation. The limits of detection (LODs for 4-nitrobenzenethiol (NBT and crystal violet (CV on this substrate are about 0.12 nM and 0.19 nM, respectively, while maximum analytical SERS enhancement factors (AEFs are about 107. In comparative assays LODs for CV measured on AuNPs@Au film and AuNPs@glass are about 0.35 nM and 2 nM, respectively. The LOD for melamine detected on AuNPs@ Al foil is 27 ppb with 3 orders of magnitude for linear response range. Overall, AuNPs@AlF demonstrated competitive performance in comparison with AuNPs@ Au film substrate in SERS detection of CV, NBT, and melamine. To check the versatility of the AuNPs@AlF substrate we also detected KNO3 with LODs of 0.7 mM and SERS EF around 2 × 103, which is on the same order with SERS EF reported for this compound in the literature.

  19. Micro-nano zinc oxide film fabricated by biomimetic mineralization: Designed architectures for SERS substrates

    Science.gov (United States)

    Lu, Fei; Guo, Yue; Wang, Yunxin; Song, Wei; Zhao, Bing

    2018-05-01

    In this study, we have investigated the effect of the surface morphologies of the zinc oxide (ZnO) substrates on surface enhanced Raman spectroscopy (SERS). During synthetic process, the self-assembly monolayers (SAMs) with different terminal groups are used as templates to induce the nucleation and growth of Zn(NO3)2·6H2O crystals, then different morphologies micro-nano ZnO powders are obtained by annealing Zn(NO3)2·6H2O crystals at 450 °C. The products obtained at different conditions are characterized by means of X-ray diffraction (XRD) patterns, scanning electron microscopy (SEM) and Raman spectra. The as-prepared ZnO micro-sized particles have been used the efficient Surface enhanced Raman scattering (SERS) substrates, and the SERS signals of 4-mercaptopyridine (Mpy) probe molecules are much influenced by the morphologies of the ZnO structures. Results indicated that the more (0001) facets appear in the of ZnO morphology, the greater degree of charge-transfer (PCT) for the SERS enhancement on the surface of semiconductors is achieved. The chemical interaction between ZnO structures and Mpy molecules plays a very important role in the SERS enhancement.

  20. A study on the correlation between the dewetting temperature of Ag film and SERS intensity.

    Science.gov (United States)

    Quan, Jiamin; Zhang, Jie; Qi, Xueqiang; Li, Junying; Wang, Ning; Zhu, Yong

    2017-11-07

    The thermally dewetted metal nano-islands have been actively investigated as cost-effective SERS-active substrates with a large area, good reproducibility and repeatability via simple fabrication process. However, the correlation between the dewetting temperature of metal film and SERS intensity hasn't been systematically studied. In this work, taking Ag nano-islands (AgNIs) as an example, we reported a strategy to investigate the correlation between the dewetting temperature of metal film and SERS intensity. We described the morphology evolution of AgNIs on the SiO 2 planar substrate in different temperatures and got the quantitative information in surface-limited diffusion process (SLDP) as a function of annealing temperature via classical mean-field nucleation theory. Those functions were further used in the simulation of electromagnetic field to obtain the correlation between the dewetting temperature of Ag film and theoretical analysis. In addition, Raman mapping was done on samples annealed at different temperatures, with R6G as an analyte, to accomplish the analysis of the correlation between the dewetting temperature of Ag film and SERS intensity, which is consistent with the theoretical analysis. For SLDP, we used the morphological characterization of five samples prepared by different annealing temperatures to successfully illustrate the change in SERS intensity with the temperature fluctuation, obtaining a small deviation between the experimental results and theoretic prediction.

  1. Effect of the size of silver nanoparticles on SERS signal enhancement

    Science.gov (United States)

    He, Rui Xiu; Liang, Robert; Peng, Peng; Norman Zhou, Y.

    2017-08-01

    The localized surface plasmon resonance arising from plasmonic materials is beneficial in solution-based and thin-film sensing applications, which increase the sensitivity of the analyte being tested. Silver nanoparticles from 35 to 65 nm in diameter were synthesized using a low-temperature method and deposited in a monolayer on a (3-aminopropyl)triethoxysilane (APTES)-functionalized glass slide. The effect of particle size on monolayer structure, optical behavior, and surface-enhanced Raman scattering (SERS) is studied. While increasing particle size decreases particle coverage, it also changes the localized surface plasmon resonance and thus the SERS activity of individual nanoparticles. Using a laser excitation wavelength of 633 nm, the stronger localized surface plasmon resonance coupling to this excitation wavelength at larger particle sizes trumps the loss in surface coverage, and greater SERS signals are observed. The SERS signal enhancement accounts for the higher SERS signal, which was verified using a finite element model of a silver nanoparticle dimer with various nanoparticle sizes and separation distances.

  2. Rapid detection of acetamiprid in foods using surface-enhanced Raman spectroscopy (SERS).

    Science.gov (United States)

    Wijaya, Wisiani; Pang, Shintaro; Labuza, Theodore P; He, Lili

    2014-04-01

    Acetamiprid is a neonicotinoid pesticide that is commonly used in modern farming. Acetamiprid residue in food commodities can be a potential harm to human and has been implicated in the honey bee hive die off crisis. In this study, we developed rapid, simple, and sensitive methods to detect acetamiprid in apple juice and on apple surfaces using surface-enhanced Raman spectroscopy (SERS). No pretreatment of apple juice sample was performed. A simple surface swab method was used to recover acetamiprid from the apple surface. Samples were incubated with silver dendrites for several minutes and SERS spectra were taken directly from the silver surface. Detection of a set of 5 apple juice samples can be done within 10 min. The swab-SERS method took 15 min for a set of 5 samples. Resulting spectral data were analyzed using principal component analysis. The highest acetamiprid peak at 634 cm(-1) was used to detect and quantify the amount of acetamiprid spiked in 1:1 water-methanol solvent, apple juice, and on apple surface. The SERS method was able to successfully detect acetamiprid at 0.5 μg/mL (0.5 ppm) in solvent, 3 μg/mL (3 ppm) in apple juice, and 0.125 μg/cm(2) on apple surfaces. The SERS methods provide simple, rapid, and sensitive ways to detect acetamiprid in beverages and on the surfaces of thick skinned fruits and vegetables. © 2014 Institute of Food Technologists®

  3. Trace determination of thiram using SERS-active hollow sea-urchin gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Guanghui; Zhang, Chuankun, E-mail: zhangchk-lx@huat.edu.cn; Ma, Yanan; Wang, Zheng; Wang, Shun; Xu, Chan; Wang, Dashuang [Hubei University of Automotive Technology, School of Science (China)

    2017-04-15

    Surface-enhanced Raman scattering (SERS) is greatly structure-dependent on the absorbed nanoparticles. Nanostructures with different novel morphologies show different Raman enhancement factor orders of magnitude. Herein, a unique nanostructure with fruitful SERS-active sites, composed of hollow interiors and thorns which named as hollow sea-urchin gold nanoparticles (HSU-GNPs), was synthesized by using a one-pot galvanic replacement method. And the corresponding morphologies and optical properties were characterized by TEM images and absorption spectra. Importantly, the synthetic parameters of HSU-GNPs were optimized to obtain a superior SERS performance by analyzing the formation mechanism and the SERS spectra of R6G-labeled HSU-GNPs which obtained at different concentrations of AgNO{sub 3}. Furthermore, the SERS-based application of HSU-GNPs was performed on the dose-response detection of thiram. The experimental result shows this detection strategy is available for thiram with decent sensitivity and reproducibility, which suggests that it is an excellent candidate for the detection of pesticides.

  4. Effects of surface topography on SERS response: Correlating nanoscopy with spectroscopy

    Science.gov (United States)

    Das, Sumit Kumar; Ghosh, Manash; Chowdhury, Joydeep

    2018-05-01

    This paper reports for the first time the hidden correlation between the topographical features of the bilayer Langmuir-Blodgett (LB) film substrates of stearic acid (SA) incubated in Au@Ag nanocolloids over various dipping times (DTs) with their corresponding SERS responses. The topographies of the as prepared substrates are investigated from the statistical considerations in terms of lateral correlation length, interface width, Hurst and Lyapnov exponents. The real space of the substrates are mapped directly from the FESEM and AFM images of the bilayer LB film of SA immersed in Au@Ag nanocolloids over various DTs ranging between 6 and 72 h. The SERS spectra of the Rhodamine 6G molecules adsorbed on the as prepared substrates have been reported. The statistical parameters of the substrates that exhibit maximum SERS efficacy have been suggested. The far field distributions in presence and in absence of Raman dipole together with spatial distribution of the near field from the hottest spot of the as prepared substrate have also been reported. To our knowledge, this is the first report that links nanoscopy with SERS spectroscopy from statistical considerations and is expected to open a new window towards the fabrication of more efficient and reproducible SERS active substrates in future endeavours.

  5. Paper based Flexible and Conformal SERS Substrate for Rapid Trace Detection on Real-world Surfaces

    Science.gov (United States)

    Singamaneni, Srikanth; Lee, Chang; Tian, Limei

    2011-03-01

    One of the important but often overlooked considerations in the design of surface enhanced Raman scattering (SERS) substrates for trace detection is the efficiency of sample collection. Conventional designs based on rigid substrates such as silicon, alumina, and glass resist conformal contact with the surface under investigation, making the sample collection inefficient. We demonstrate a novel SERS substrate based on common filter paper adsorbed with gold nanorods, which allows conformal contact with real-world surfaces, thus dramatically enhancing the sample collection efficiency compared to conventional rigid substrates. We demonstrate the detection of trace amounts of analyte (140 pg spread over 4 cm2) by simply swabbing the surface under investigation with the novel SERS substrate. The hierarchical fibrous structure of paper serves as a 3D vasculature for easy uptake and transport of the analytes to the electromagnetic hot spots in the paper. Simple yet highly efficient and cost effective SERS substrate demonstrated here brings SERS based trace detection closer to real-world applications. We acknowledge the financial support from Center for Materials Innovation at Washington University.

  6. Modos de ser enfermeiro-professor-no-ensino-do-cuidadode-enfermagem: um olhar heideggeriano

    Directory of Open Access Journals (Sweden)

    Luciara Fabiane Sebold

    2013-08-01

    Full Text Available Estudo qualitativo de abordagem fenomenológica. Objetivou desvelar, à luz do pensamento de Martin Heidegger, os modos de ser dos enfermeiros-professores na vivência de ensinar-aprender o cuidado de enfermagem em uma instituição federal de ensino superior do sul do Brasil. A técnica utilizada para captar os significados foi a entrevista fenomenológica com 11 docentes. A análise permitiu compreender os Modos de Ser enfermeiro-professor, que foram didaticamente apresentados em duas unidades de significado: Modo de ser enfermeiro para o cuidado; Modo de ser professor para o ensino do cuidado. Alguns professores identificam-se como enfermeiros, suas experiências profissionais são suas bases e a coexistência com outros pôde lhes servir de exemplo. Outros se percebem professores de enfermagem e desejam ensinar os desafios de ser enfermeiro, e aprimoram o cuidado através de pesquisas. Ao ensinar, envolvem-se com o universo de ensino no qual o cuidar também é aprender e ensinar.

  7. Pro-106-Ser mutation and EPSPS overexpression acting together simultaneously in glyphosate-resistant goosegrass (Eleusine indica).

    Science.gov (United States)

    Gherekhloo, Javid; Fernández-Moreno, Pablo T; Alcántara-de la Cruz, Ricardo; Sánchez-González, Eduardo; Cruz-Hipolito, Hugo E; Domínguez-Valenzuela, José A; De Prado, Rafael

    2017-07-27

    Glyphosate has been used for more than 15 years for weed management in citrus groves in the Gulf of Mexico, at up to 3-4 applications per year. Goosegrass (Eleusine indica (L.) Gaertn.) control has sometimes failed. In this research, the mechanisms governing three goosegrass biotypes (Ein-Or from an orange grove, and Ein-Pl1 and Ein-Pl2 from Persian lime groves) with suspected resistance to glyphosate were characterized and compared to a susceptible biotype (Ein-S). Dose-response and shikimate accumulation assays confirmed resistance of the resistant (R) biotypes. There were no differences in glyphosate absorption, but the R biotypes retained up to 62-78% of the herbicide in the treated leaf at 96 h after treatment (HAT), in comparison to the Ein-S biotype (36%). The 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) activity in the Ein-Or and Ein-S biotypes was over 100-fold lower than the Ein-Pl1 and Ein-Pl2 ones. The latter showed a high EPSPS-basal activity, a mutation at Pro-106-Ser position in the EPSPS gene, and EPSPS overexpression. The EPSPS basal and EPSPS overexpression were positively correlated. The R goosegrass biotypes displayed poor glyphosate translocation. Furthermore, this grassweed showed, for the first time, two mechanisms at the target-site level (Pro-106-Ser mutation + EPSPS overexpression) acting together simultaneously against glyphosate.

  8. Continual evolution: the experience over three semesters of a librarian embedded in an online evidence-based medicine course for physician assistant students.

    Science.gov (United States)

    Kealey, Shannon

    2011-01-01

    This column examines the experience, over three years, of a librarian embedded in an online Epidemiology and Evidence-based Medicine course, which is a requirement for students pursuing a Master of Science in Physician Assistant Studies at Pace University. Student learning outcomes were determined, a video lecture was created, and student learning was assessed via a five-point Blackboard test during year one. For years two and three, the course instructor asked the librarian to be responsible for two weeks of course instruction and a total of 15 out of 100 possible points for the course. This gave the librarian flexibility to measure additional outcomes and gather more in-depth assessment data. The librarian then used the assessment data to target areas for improvement in the lessons and Blackboard tests. Revisions made by the librarian positively affected student achievement of learning outcomes, as measured by the assessment conducted the subsequent semester. Plans for further changes are also discussed.

  9. SERS investigations and electrical recording of neuronal networks with three-dimensional plasmonic nanoantennas (Conference Presentation)

    Science.gov (United States)

    De Angelis, Francesco

    2017-06-01

    SERS investigations and electrical recording of neuronal networks with three-dimensional plasmonic nanoantennas Michele Dipalo, Valeria Caprettini, Anbrea Barbaglia, Laura Lovato, Francesco De Angelis e-mail: francesco.deangelis@iit.it Istituto Italiano di Tecnologia, Via Morego 30, 16163, Genova Biological systems are analysed mainly by optical, chemical or electrical methods. Normally each of these techniques provides only partial information about the environment, while combined investigations could reveal new phenomena occurring in complex systems such as in-vitro neuronal networks. Aiming at the merging of optical and electrical investigations of biological samples, we introduced three-dimensional plasmonic nanoantennas on CMOS-based electrical sensors [1]. The overall device is then capable of enhanced Raman Analysis of cultured cells combined with electrical recording of neuronal activity. The Raman measurements show a much higher sensitivity when performed on the tip of the nanoantenna in respect to the flat substrate [2]; this effect is a combination of the high plasmonic field enhancement and of the tight adhesion of cells on the nanoantenna tip. Furthermore, when plasmonic opto-poration is exploited [3] the 3D nanoelectrodes are able to penetrate through the cell membrane thus accessing the intracellular environment. Our latest results (unpublished) show that the technique is completely non-invasive and solves many problems related to state-of-the-art intracellular recording approaches on large neuronal networks. This research received funding from ERC-IDEAS Program: "Neuro-Plasmonics" [Grant n. 616213]. References: [1] M. Dipalo, G. C. Messina, H. Amin, R. La Rocca, V. Shalabaeva, A. Simi, A. Maccione, P. Zilio, L. Berdondini, F. De Angelis, Nanoscale 2015, 7, 3703. [2] R. La Rocca, G. C. Messina, M. Dipalo, V. Shalabaeva, F. De Angelis, Small 2015, 11, 4632. [3] G. C. Messina et al., Spatially, Temporally, and Quantitatively Controlled Delivery of

  10. Mathematical models of physics problems (physics research and technology)

    CERN Document Server

    Anchordoqui, Luis Alfredo

    2013-01-01

    This textbook is intended to provide a foundation for a one-semester introductory course on the advanced mathematical methods that form the cornerstones of the hard sciences and engineering. The work is suitable for first year graduate or advanced undergraduate students in the fields of Physics, Astronomy and Engineering. This text therefore employs a condensed narrative sufficient to prepare graduate and advanced undergraduate students for the level of mathematics expected in more advanced graduate physics courses, without too much exposition on related but non-essential material. In contrast to the two semesters traditionally devoted to mathematical methods for physicists, the material in this book has been quite distilled, making it a suitable guide for a one-semester course. The assumption is that the student, once versed in the fundamentals, can master more esoteric aspects of these topics on his or her own if and when the need arises during the course of conducting research. The book focuses on two cor...

  11. EFEKTIFITAS PENGGUNAAN METODE EKSPERIMEN DALAM PEMBELAJARAN FISIKA KELAS X SEMESTER GANJIL SMAN 1 KALIREJO TAHUN PELAJARAN 2013/2014

    Directory of Open Access Journals (Sweden)

    Wahyudi .

    2014-03-01

    Full Text Available The student learning outcomes in SMAN 1 Kalirejo academic year 2012/2013 show the results that many of students doesn't reach the KKM 70. In learning most of the students think that physics is one of difficult subject, bored, and complicated subject. they do not give their attention when thr learning proccess is running. There is nothing interaction and discussion between the student one the other's to discuss about the physics. the objectives of this research is know how the quality of the learning process in terms of student activity, based on the teacher activity, how the students learning respond, and how the students mastery in learning physics. Technique sampling in this research using is cluster random sampling technique, from 5 classes.To get the real data the research using tests, quesionnaires and observations. And to count the data effectivity the researcher using experiment method every indicator will be count by using experiment method. It start from multipled the each indicator then it will devided by how much indicator it self and the result of its will be times by 100%. The conclusion of the research in the use of the effective experiment method in teaching physics. thr score is 3.25 as shown by (1 the quality of learning process in terms of student's activity in high percentaage 81.2% in high ccategorize (2 the quality of lesson good enough if the percentage it is about 75% from teacher activity, (3 the student's respond after they got the method is positive it shows by the respond percentage 80,20%, (4 the result of individual student's score has the avarege value 78.8 and from the clasical student got 87.8%, all of thr score is high categorize. Researchers suggest subjects physics teacher when delivering measuring the amount of material should be used experiment method for learning effective, for students should be serious in implementing learning and doing each activity well to the result obtained either.

  12. Synthesis of Dendritic Silver Nanoparticles and Their Applications as SERS Substrates

    Directory of Open Access Journals (Sweden)

    Jinshan Yu

    2013-01-01

    Full Text Available The silver nanoparticles are synthesized by electrodeposition in ultradilute Ag+ concentration electrolyte under high overpotential. The as prepared Ag nanoparticles, with the sizes ranging from 20 to 30 nm, are arrayed orderly and formed dendritic morphology. The formation of this special dendritic nanoparticle structure can be contributed to the relatively high growth rate and the preferential growth directions along 111 due to the high overpotential, as well as the relative small number of Ag+ ions arriving at the Ag crystal surface per unit time due to the ultradilute Ag+ concentration. Surface enhanced Raman scattering (SERS experiments reveal that the as-prepared dendritic Ag nanoparticles possess high SERS properties and can be used as a candidate substrate for practical SERS applications to detect the Rhodamine 6G molecules.

  13. Reproducible and recyclable SERS substrates: Flower-like Ag structures with concave surfaces formed by electrodeposition

    Science.gov (United States)

    Bian, Juncao; Shu, Shiwei; Li, Jianfu; Huang, Chao; Li, Yang Yang; Zhang, Rui-Qin

    2015-04-01

    Direct synthesis of three-dimensional Ag structures on solid substrates for the purposes of producing reproducible and recyclable surface-enhanced Raman scattering (SERS) applications remains challenging. In this work, flower-like Ag structures with concave surfaces (FACS) were successfully electrodeposited onto ITO glass using the double-potentiostatic method. The FACS, with an enhancement factor of the order of 108, exhibited a SERS signal intensity 3.3 times stronger than that measured from Ag nanostructures without concave surfaces. A cleaning procedure involving lengthy immersion of the sample in ethanol and KNO3 was proposed to recycle the substrate and confirmed by using rhodamine 6G, adenine, and 4-aminothiophenol as target molecules. The findings can help to advance the practical applications of Ag nanostructure-based SERS substrates.

  14. Acerca de la doctrina de la indestructibilidad de nuestro verdadero ser por la muerte

    OpenAIRE

    Schopenhauer, Arthur

    2010-01-01

    "Acerca de la doctrina de la indestructibilidad de nuestro verdadero ser por la muerte" es un escrito complementario del famoso capítulo 41 del Tomo II de El mundo como voluntad y representación, que lleva el paradójico título: "Sobre la muerte y su relación con la indestructibilidad de nuestro ser en sí" . El título es paradójico porque Schopenhauer habla de "nuestro ser en sí" y no parece fácilmente concebible la adscripción del posesivo"nuestro" a lo que"es en sí", o sea, a lo que existe i...

  15. Quantification of Protein Biomarker Using SERS Nano-Stress Sensing with Peak Intensity Ratiometry

    Science.gov (United States)

    Goh, Douglas; Kong, Kien Voon; Jayakumar, Perumal; Gong, Tianxun; Dinish, U. S.; Olivo, Malini

    We report a surface enhanced Raman spectroscopy (SERS) ratiometry method based on peak intensity coupled in a nano-stress sensing platform to detect and quantify biological molecules. Herein, we employed an antibody-conjugated p-aminothiophenol (ATP) functionalized on a bimetallic-film-over-nanosphere (BMFON) substrate as a sensitive SERS platform to detect human haptoglobin (Hp) protein, which is an acute phase protein and a biomarker for various cancers. Correlation between change in the ATP spectral characteristics and concentration of Hp protein was established by examining the peak intensity ratio at 1572cm-1 and 1592cm-1 that reflects the degree of stress experienced by the aromatic ring of ATP during Hp protein-antibody interaction. Development of this platform shows the potential in developing a low-cost and sensitive SERS sensor for the pre-screening of various biomarkers.

  16. Porous Au-Ag Nanospheres with High-Density and Highly Accessible Hotspots for SERS Analysis.

    Science.gov (United States)

    Liu, Kai; Bai, Yaocai; Zhang, Lei; Yang, Zhongbo; Fan, Qikui; Zheng, Haoquan; Yin, Yadong; Gao, Chuanbo

    2016-06-08

    Colloidal plasmonic metal nanoparticles have enabled surface-enhanced Raman scattering (SERS) for a variety of analytical applications. While great efforts have been made to create hotspots for amplifying Raman signals, it remains a great challenge to ensure their high density and accessibility for improved sensitivity of the analysis. Here we report a dealloying process for the fabrication of porous Au-Ag alloy nanoparticles containing abundant inherent hotspots, which were encased in ultrathin hollow silica shells so that the need of conventional organic capping ligands for stabilization is eliminated, producing colloidal plasmonic nanoparticles with clean surface and thus high accessibility of the hotspots. As a result, these novel nanostructures show excellent SERS activity with an enhancement factor of ∼1.3 × 10(7) on a single particle basis (off-resonant condition), promising high applicability in many SERS-based analytical and biomedical applications.

  17. Fe2O3-Au hybrid nanoparticles for sensing applications via sers analysis

    International Nuclear Information System (INIS)

    Murph, Simona Hunyadi; Searles, Emily

    2017-01-01

    Nanoparticles with large amounts of surface area and unique characteristics that are distinct from their bulk material provide an interesting application in the enhancement of inelastic scattering signal. Surface Enhanced Raman Spectroscopy (SERS) strives to increase the Raman scattering effect when chemical species of interest are in the close proximity of metallic nnaostructures. Gold nanoparticles of various shapes have been used for sensing applications via SERS as they demonstrate the greatest effect of plasmonic behavior in the visible-near IR region of the spectrum. When coupled with other nanoparticles, namely iron oxide nanoparticles, hybrid structures with increased functionality were produced. Multifunctional iron oxide-gold hybrid nanostructures have been created via solution chemistries and investigated for analyte detection of a model analyte. By exploiting their magnetic properties, nanogaps or “hot spots” were rationally created and evaluated for SERS enhancement studies.

  18. Effect of Etching on the Optical, Morphological Properties of Ag Thin Films for SERS Active Substrates

    Directory of Open Access Journals (Sweden)

    Desapogu Rajesh

    2013-01-01

    Full Text Available Structural, optical, and morphological properties of Ag thin films before and after etching were investigated by using X-ray diffraction, UV-Vis spectrophotometer, and field emission scanning electron microscopy (FESEM. The HNO3 roughened Ag thin films exhibit excellent enhancement features and better stability than pure Ag thin films. Further, the Ag nanostructures are covered with Rhodamine 6G (Rh6G and then tested with surface enhanced raman spectroscopy (SERS for active substrates. Etched Ag films were found to exhibit a strong SERS effect and excellent thermal stability. Hence, the present method is found to be useful in the development of plasmon-based analytical devices, especially SERS-based biosensors.

  19. Combining surface enhanced Raman scattering (SERS) and high-performance thin-layer chromatography (HPTLC)

    Science.gov (United States)

    Koglin, E.

    A new method for preparing SERS active surfaces using silver colloidal spheres deposited on HPTLC plates, used for thin-layer chromatography, is discussed in detail. The sensitivity of these activated HPTLC plates is so high that in-situ vibrational investigations of chromatogram spots are possible at the nanogram level. The HPTLC/SERS spectra of purine, benzoic acid and 1-nitro-pyrene adsorbed on silver colloidal activated silica gel plates are measured in the nanogram region. In addition we also report in this paper on the results of a feasibility study performed to evaluate the analytical potential of micro-Raman spectroscopy (triple monochromator, multichannel detection system) in SERS/HPTLC spot characterization. It permits the acquisition of Raman spectra from HPTLC spots down to 1 μm in size or other forms of microsamples approaching the picogram level in mass.

  20. Ultra-thin layer chromatography with integrated silver colloid-based SERS detection.

    Science.gov (United States)

    Wallace, Ryan A; Lavrik, Nickolay V; Sepaniak, Michael J

    2017-01-01

    Simplified lab-on-a-chip techniques are desirable for quick and efficient detection of analytes of interest in the field. The following work involves the use of deterministic pillar arrays on the micro-scale as a platform to separate compounds, and the use of Ag colloid within the arrays as a source of increased signal via surface enhanced Raman spectroscopy (SERS). One problem traditionally seen with SERS surfaces containing Ag colloid is oxidation; however, our platforms are superhydrophobic, reducing the amount of oxidation taking place on the surface of the Ag colloid. This work includes the successful separation and SERS detection of a fluorescent dye compounds (resorufin and sulforhodamine 640), fluorescent anti-tumor drugs (Adriamycin and Daunomycin), and purine and pyrimidine bases (adenine, cytosine, guanine, hypoxanthine, and thymine). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Controllable Ag nanostructure patterning in a microfluidic channel for real-time SERS systems.

    Science.gov (United States)

    Leem, Juyoung; Kang, Hyun Wook; Ko, Seung Hwan; Sung, Hyung Jin

    2014-03-07

    We present a microfluidic patterning system for fabricating nanostructured Ag thin films via a polyol method. The fabricated Ag thin films can be used immediately in a real-time SERS sensing system. The Ag thin films are formed on the inner surfaces of a microfluidic channel so that a Ag-patterned Si wafer and a Ag-patterned PDMS channel are produced by the fabrication. The optimum sensing region and fabrication duration for effective SERS detection were determined. As SERS active substrates, the patterned Ag thin films exhibit an enhancement factor (EF) of 4.25 × 10(10). The Ag-patterned polymer channel was attached to a glass substrate and used as a microfluidic sensing system for the real-time monitoring of biomolecule concentrations. This microfluidic patterning system provides a low-cost process for the fabrication of materials that are useful in medical and pharmaceutical detection and can be employed in mass production.

  2. Tatuajes y su eliminación por láser

    Directory of Open Access Journals (Sweden)

    T. Castro

    Full Text Available La eliminación de los tatuajes con buen resultado cosmético ha sido una inquietud mantenida durante siglos. La introducción del tratamiento láser ha supuesto un avance importante de cara a obtener buenos resultados con mínimos efectos secundarios. En este trabajo se exponen los diferentes tipos de tatuajes con sus características de pigmento, origen, tipos de tratamientos para su eliminación, y entre ellos, la utilización de la tecnología láser, más concretamente de los láseres de emisión en Q-Switch con sus ventajas y limitaciones. Presentamos también los avances y el futuro de la aplicación del láser en el tratamiento de los tatuajes.

  3. Synthesis by picosecond laser ablation of ligand-free Ag and Au nanoparticles for SERS applications

    Science.gov (United States)

    Fazio, Enza; Spadaro, Salvatore; Santoro, Marco; Trusso, Sebastiano; Lucotti, Andrea.; Tommasini, Matteo.; Neri, Fortunato; Maria Ossi, Paolo

    2018-01-01

    The morphological and optical properties of noble metal nanoparticles prepared by picosecond laser generated plasmas in water were investigated. First, the ablation efficiency was maximized searching the optimal focusing conditions. The nanoparticle size, measured by Scanning Transmission Electron Microscopy, strongly depends on the laser fluence, keeping fixed the other deposition parameters such as the target to scanner objective distance and laser repetition frequency. STEM images indicate narrow gradients of NP sizes. Hence the optimization of ablation parameters favours a fine tuning of nanoparticles. UV-Visible spectroscopy helped to determine the appropriate laser wavelength to resonantly excite the localized surface plasmon to carry out Surface Enhanced Raman Scattering (SERS) measurements. The SERS activity of Ag and Au substrates, obtained spraying the colloids synthesized in water, was tested using crystal violet as a probe molecule. The good SERS performance, observed at excitation wavelength 785 nm, is attributed to aggregation phenomena of nanoparticles sprayed on the support.

  4. Design of Hybrid Nanostructural Arrays to Manipulate SERS-Active Substrates by Nanosphere Lithography.

    Science.gov (United States)

    Zhao, Xiaoyu; Wen, Jiahong; Zhang, Mengning; Wang, Dunhui; Wang, Yaxin; Chen, Lei; Zhang, Yongjun; Yang, Jinghai; Du, Youwei

    2017-03-01

    An easy-handling and low-cost method is utilized to controllably fabricate nanopattern arrays as the surface-enhanced Raman scattering (SERS) active substrates with high density of SERS-active areas (hot spots). A hybrid silver array of nanocaps and nanotriangles are prepared by combining magnetron sputtering and plasma etching. By adjusting the etching time of polystyrene (PS) colloid spheres array in silver nanobowls, the morphology of the arrays can be easily manipulated to control the formation and distribution of hot spots. The experimental results show that the hybrid nanostructural arrays have large enhancement factor, which is estimated to be seven times larger than that in the array of nanocaps and three times larger than that in the array of nanorings and nanoparticles. According to the results of finite-difference time-domain simulation, the excellent SERS performance of this array is ascribed to the high density of hot spots and enhanced electromagnetic field.

  5. Recognition of peptidoglycan and beta-lactam antibiotics by the extracellular domain of the Ser/Thr protein kinase StkP from Streptococcus pneumoniae

    Czech Academy of Sciences Publication Activity Database

    Maestro, B.; Nováková, Linda; Hesek, D.; Lee, M.; Leyva, E.; Mobashery, S.; Sanz, J.M.; Branny, Pavel

    2011-01-01

    Roč. 585, č. 2 (2011), s. 357-363 ISSN 0014-5793 R&D Projects: GA ČR GP204/07/P082; GA ČR GA204/08/0783; GA AV ČR IAA600200801 Institutional research plan: CEZ:AV0Z50200510 Keywords : Signal transduction * Penicillin-binding protein and Ser/Thr protein kinase-associated domain * Peptidoglycan Subject RIV: CE - Biochemistry Impact factor: 3.538, year: 2011

  6. Quaternized chitosan/silver nanoparticles composite as a SERS substrate for detecting tricyclazole and Sudan I

    International Nuclear Information System (INIS)

    Chen, Kaihang; Shen, Zuguang; Luo, Jiwen; Wang, Xiaoying; Sun, Runcang

    2015-01-01

    Graphical abstract: - Highlights: • Synthesis optimization of Ag NPs with quaternized chitosan (QCS) was studied. • The size of Ag NPs was tuned by changing the DS and Mw of QCS. • QCS/Ag NPs exhibited much better SERS performance than Ag NPs without free QCS. • QCS/Ag NPs as SERS substrate detected tricyclazole in low concentration of 50 ppb. • QCS/Ag NPs as SERS substrate detected Sudan I with the detection limit of 10 ppm. - Abstract: There is an urgent need to develop a highly sensitive detection system for detecting trace amounts of food contaminants. In this study, optimal synthesis of silver nanoparticles (Ag NPs) with stable and narrow size distribution in the range of 15–25 nm was performed under microwave irradiation, using quaternized chitosan (QCS) as reducing and stabilizing agent. The results showed that the ratio of QCS to [Ag(NH 3 ) 2 ] + , reaction temperature, irradiation time, the degree of substitution (DS) and molecular weight (Mw) of QCS had obvious effects on the formation, particle size and size distribution of Ag NPs. In addition, utilizing QCS/Ag NPs composite as SERS substrate, tricyclazole and Sudan I could be rapidly and sensitively detected with the limit of detection (LOD) as low as 50 ppb and 10 ppm, respectively. Compared with previously reported works, our detection system are of great stability and operability. The QCS was coated on the surface of Ag core, avoiding aggregation of Ag NPs and creating hot spots, in turn, providing superior amplification of SERS. Thus, it is believed that the QCS/Ag NPs composite could be considered as an ideal SERS-active substrate for detection of food contaminants

  7. Quaternized chitosan/silver nanoparticles composite as a SERS substrate for detecting tricyclazole and Sudan I

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Kaihang; Shen, Zuguang [State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640 (China); Luo, Jiwen, E-mail: holdit@126.com [State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640 (China); Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Wang, Xiaoying, E-mail: xyw@scut.edu.cn [State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640 (China); Sun, Runcang [State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640 (China); Institute of Biomass Chemistry and Technology, Beijing Forestry University, Beijing 100083 (China)

    2015-10-01

    Graphical abstract: - Highlights: • Synthesis optimization of Ag NPs with quaternized chitosan (QCS) was studied. • The size of Ag NPs was tuned by changing the DS and Mw of QCS. • QCS/Ag NPs exhibited much better SERS performance than Ag NPs without free QCS. • QCS/Ag NPs as SERS substrate detected tricyclazole in low concentration of 50 ppb. • QCS/Ag NPs as SERS substrate detected Sudan I with the detection limit of 10 ppm. - Abstract: There is an urgent need to develop a highly sensitive detection system for detecting trace amounts of food contaminants. In this study, optimal synthesis of silver nanoparticles (Ag NPs) with stable and narrow size distribution in the range of 15–25 nm was performed under microwave irradiation, using quaternized chitosan (QCS) as reducing and stabilizing agent. The results showed that the ratio of QCS to [Ag(NH{sub 3}){sub 2}]{sup +}, reaction temperature, irradiation time, the degree of substitution (DS) and molecular weight (Mw) of QCS had obvious effects on the formation, particle size and size distribution of Ag NPs. In addition, utilizing QCS/Ag NPs composite as SERS substrate, tricyclazole and Sudan I could be rapidly and sensitively detected with the limit of detection (LOD) as low as 50 ppb and 10 ppm, respectively. Compared with previously reported works, our detection system are of great stability and operability. The QCS was coated on the surface of Ag core, avoiding aggregation of Ag NPs and creating hot spots, in turn, providing superior amplification of SERS. Thus, it is believed that the QCS/Ag NPs composite could be considered as an ideal SERS-active substrate for detection of food contaminants.

  8. Paper membrane-based SERS platform for the determination of glucose in blood samples.

    Science.gov (United States)

    Torul, Hilal; Çiftçi, Hakan; Çetin, Demet; Suludere, Zekiye; Boyacı, Ismail Hakkı; Tamer, Uğur

    2015-11-01

    In this report, we present a paper membrane-based surface-enhanced Raman scattering (SERS) platform for the determination of blood glucose level using a nitrocellulose membrane as substrate paper, and the microfluidic channel was simply constructed by wax-printing method. The rod-shaped gold nanorod particles were modified with 4-mercaptophenylboronic acid (4-MBA) and 1-decanethiol (1-DT) molecules and used as embedded SERS probe for paper-based microfluidics. The SERS measurement area was simply constructed by dropping gold nanoparticles on nitrocellulose membrane, and the blood sample was dropped on the membrane hydrophilic channel. While the blood cells and proteins were held on nitrocellulose membrane, glucose molecules were moved through the channel toward the SERS measurement area. Scanning electron microscopy (SEM) was used to confirm the effective separation of blood matrix, and total analysis is completed in 5 min. In SERS measurements, the intensity of the band at 1070 cm(-1) which is attributed to B-OH vibration decreased depending on the rise in glucose concentration in the blood sample. The glucose concentration was found to be 5.43 ± 0.51 mM in the reference blood sample by using a calibration equation, and the certified value for glucose was 6.17 ± 0.11 mM. The recovery of the glucose in the reference blood sample was about 88 %. According to these results, the developed paper-based microfluidic SERS platform has been found to be suitable for use for the detection of glucose in blood samples without any pretreatment procedure. We believe that paper-based microfluidic systems may provide a wide field of usage for paper-based applications.

  9. The Implementation of Role Play to Improve EFL Speaking Skill of the Second Semester Students of Akademi Bahasa Asing Balikpapan

    Directory of Open Access Journals (Sweden)

    Muhammad Rochman

    2014-08-01

    Full Text Available Speaking is an important skill learned by English student although English covers four skills namely speaking, listening, speaking and writing. Speaking is the main bridge for the students to master English. Unfortunately the fact has shown that the students were quite difficult to improve their speaking skill because they were accustomed to use their native language language in their daily life than using English. The above facts signify that the lecturer should apply the techniques that can motivate students to speak and engage students in encouraging activities. One of the techniques that encourage students to speak is role play. Role play is the choice implemented by the researcher in improving the speaking skill of the first year students at ABA Balikpapan since using role play, the students can express their idea, opinion, and feeling well in their performance without being worried to make mistake. Based on the result of the study, it can be concluded that the result of this research was satisfying. This research claims that it was successful in the effort in improving students’ English speaking skill through Role-Play. Role-Play activity could increase the students’ motivation in joining the teaching and learning activity. Their motivation is reflected in their efforts in preparing the Role-Play.

  10. Project W-320, waste retrieval sluicing system: BIO/SER implementation matrices

    International Nuclear Information System (INIS)

    Bailey, J.W.

    1998-01-01

    This document provides verification that the safety related commitments specified in HNF-SD-WM-810-001, Addendum 1 for the Waste Retrieval Sluicing System, Project W-320 and Project W-320 Safety Evaluation Report (SER), have been implemented in the project hardware, procedures and administrative controls. Four appendices include matrices which show where the 810 commitments are implemented for limiting conditions of operation and surveillance requirements controls, administrative controls, defense-in-depth controls and controls discussed in 810 Addendum 1. A fifth appendix includes the implementation of Project W-320 SER issues and provisions

  11. SERS spectra of pyridine adsorbed on nickel film prepared by magnetron sputtering

    Science.gov (United States)

    Li, Daoyong; Ouyang, Yu; Chen, Li; Cao, Weiran; Shi, Shaohua

    2011-02-01

    As a repeating well and cheaper enhancement substrate, the nickel film was fabricated with magnetron sputtering coating instrument. Surface enhanced Raman spectra (SERS) of pyridine adsorbed on this nickel film are compared with the experimental values of gaseous pyridine, the theoretical value of pyridine solution listed in other literatures and our method is better than electro-chemical etching electrode method for large scale preparation. The enhancement factor of the nickel film is calculated and the result indicates that magnetron sputtering coating technology is feasible for obtaining good SERS active surface.

  12. Ser educador(a é ... (também socializar inquietações

    Directory of Open Access Journals (Sweden)

    Sandra Marisa Allebrandt-Padilha

    2011-11-01

    Full Text Available O presente artigo convida os educadores a refletir sobre questões candentes do cotidiano escolar, tais como: o sofrimento diante do aluno que não aprende, o mal-estar-docente decorrente das transformações sociopolíticas que convergem para a Educação Inclusiva. Nessa perspectiva, com o propósito de buscar respostas para a Educação na Diversidade, elegemos algumas iniciativas que desafiam aqueles que desejam ser protagonistas no ofício SER EDUCADOR.Palavras-chave: Cotidiano Escolar. Dificuldade de Aprendizagem. Educação Inclusiva, Mal-Estar-Docente. Diversidade..

  13. PGC-1alpha Gly482Ser polymorphism associates with hypertension among Danish whites

    DEFF Research Database (Denmark)

    Andersen, Gitte; Wegner, Lise; Jensen, Dorit Packert

    2005-01-01

    in combination with previously published results. The Ser/Ser genotype was significantly associated with a reduced risk of hypertension and with lower systolic, diastolic, and mean arterial blood pressure levels, predominantly among women. Finally, in a combined analysis using data obtained in both sexes...... to elucidate the differential role of this polymorphism in men and women.......PGC-1alpha is a coactivator of numerous transcription factors and is expressed in tissues with high energy demands and abundant in mitochondria. It is induced in the myocardium on fasting and physical exercise, and cardiac-specific overexpression stimulates mitochondrial biogenesis in mice...

  14. SERS analysis of Ag nanostructures produced by ion-beam deposition

    Science.gov (United States)

    Atanasov, P. A.; Nedyalkov, N. N.; Nikov, Ru G.; Grüner, Ch; Rauschenbach, B.; Fukata, N.

    2018-03-01

    This study deals with the development of a novel technique for formation of advanced Ag nanostructures (NSs) to be applied to high-resolution analyses based on surface enhanced Raman scattering (SERS). It has direct bearing on human health and food quality, e.g., monitoring small amount or traces of pollutants or undesirable additives. Three types of nanostructured Ag samples were produced using ion-beam deposition at glancing angle (GLAD) on quartz. All fabricated structures were covered with BI-58 pesticide (dimethoate) or Rhodamine 6G (R6G) for testing their potential for use as substrates for (SERS).

  15. Nanostructured Silver Substrates With Stable and Universal SERS Properties: Application to Organic Molecules and Semiconductor Nanoparticles

    Directory of Open Access Journals (Sweden)

    Waurisch C

    2009-01-01

    Full Text Available Abstract Nanostructured silver films have been prepared by thermal deposition on silicon, and their properties as SERS substrates investigated. The optimal conditions of the post-growth annealing of the substrates were established. Atomic force microscopy study revealed that the silver films with relatively dense and homogeneous arrays of 60–80-nm high pyramidal nanoislands are the most efficient for SERS of both organic dye and inorganic nanoparticles analytes. The noticeable enhancement of the Raman signal from colloidal nanoparticles with the help of silver island films is reported for the first time.

  16. Students' Framing of a Reading Annotation Tool in the Context of Research-Based Teaching

    Science.gov (United States)

    Dahl, Jan Erik

    2016-01-01

    In the studied master's course, students participated both as research objects in a digital annotation experiment and as critical investigators of this technology in their semester projects. The students' role paralleled the researcher's role, opening an opportunity for researcher-student co-learning within what is often referred to as…

  17. The Impact of a Multifaceted Approach to Teaching Research Methods on Students' Attitudes

    Science.gov (United States)

    Ciarocco, Natalie J.; Lewandowski, Gary W., Jr.; Van Volkom, Michele

    2013-01-01

    A multifaceted approach to teaching five experimental designs in a research methodology course was tested. Participants included 70 students enrolled in an experimental research methods course in the semester both before and after the implementation of instructional change. When using a multifaceted approach to teaching research methods that…

  18. Being elderly with functional dependence and their family caregivers Ser anciano con incapacidad y sus cuidadores familiares Ser idoso com incapacidade e seus cuidadores familiares

    Directory of Open Access Journals (Sweden)

    Amanda Maria Souza de Oliveira

    2012-01-01

    Full Text Available OBJECTIVE: To identify the authors` point of discussion on the elderly with functional dependence, correlating it with the ontological time discussed in Heidegger. METHODS: This is a bibliographic, systematic and qualitative study. Data was collected in the Scientific Electronic Library Online database. A total of 123 studies were identified, 15 studies were included considering the inclusion criteria. RESULTS: Based on the semantic analysis of Bardin, the following categories of analysis were established: being caregiver for the elderly with functional dependence, being elderly with functional dependence, family dynamics. CONCLUSION: It was understood that factors related to the worldliness of these people as family relationships, support of formal and informal services, economic and social situation, among others, are part of the history of these people influencing their modes of being. Searching to understand these factors is important to promote the health of these people, thinking of the biological and existential care.OBJETIVO: Identificar el punto de discusión de los autores sobre el anciano con incapacidad funcional, correlacionando con el tiempo ontológico heideggeriano. MÉTODOS: Estudio de tipo bibliográfico, sistemático y cualitativo. Los datos fueron recolectados en el banco de datos del Scientific Electronic Library Online. De un total de 123 publicaciones identificadas, fueron seleccionados 15 estudios, de acuerdo a los criterios de inclusión adoptados. RESULTADOS: Con base en el análisis temático de Bardin, fueron constituídas las siguientes categorías de análisis: ser-cuidador del anciano con incapacidad, ser-anciano con incapacidad, dinámica familiar. CONCLUSIÓN: Se comprendió que los factores relacionados a a relación familiar, apoyo de los servicios formales e informales, situación económica, social, entre otras, forman parte de la historicidad de éstas influenciando su modo de ser. Es importante buscar la

  19. The academic journey of university students on Facebook: an analysis of informal academic-related activity over a semester

    Directory of Open Access Journals (Sweden)

    Rebecca Vivian

    2014-08-01

    Full Text Available This paper reports on an observation of 70 university students’ use of their personal social network site (SNS, Facebook, over a 22-week university study period. The study sought to determine the extent that university students use their personal SNSs to support learning by exploring frequencies of academic-related content and topics being discussed. The findings reported in the paper reveal that students used their personal SNSs to discuss academic-related topics, particularly to share experiences about doing work or procrastinating, course content and grades. Mapping academic-related activity frequencies over the 22 weeks illustrated that around certain points in the academic calendar, particularly times when students’ assignments or exams were nearing, academic activity increased, suggesting that SNSs may play an important role in a students’ academic experience.The findings suggest that many students today may be leaving traces of their academic journey online and that academics should be aware that these interactions may also exist in their own students’ online social spaces. This study offers opportunities for future research, particularly research which seeks to determine differences between individuals' academic activity, the extent that intensive SNSs use supports or distracts students from learning, as well as the extent to which universities should or can harness SNSs to improve the student experience.

  20. Ser hombre o ser mujer a través de la música: una encuesta a jóvenes de Barcelona

    OpenAIRE

    Martí,Josep

    1999-01-01

    Este artigo trata da problemática da relação entre gênero e música. Sabemos que a música como meio de comunicação contribui também para a construção social da realidade; se nos interessamos pela música como fenômeno sócio-cultural, então o aspecto de gênero constitui uma dimensão que não pode ser ignorada. Ao longo deste artigo, apresentarei alguns dados relativos a uma pesquisa tipo survey realizada com...

  1. Development research in the Southern Cone | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2011-01-05

    Jan 5, 2011 ... In Chile alone, some 3 000 social scientists left the country after the 1973 coup; in 1980, more than 500 professors were fired from Chilean universities in a single semester. The coercive suppression of social science research menaced lives and livelihoods — and undercut the region's prospects for future ...

  2. Preparing School Leaders: Action Research on the Leadership Study Group

    Science.gov (United States)

    Kamler, Estelle

    2016-01-01

    This article reports an action research study that examined the Leadership Study Group, one learning activity designed to build knowledge and skills for aspiring school leaders and implemented in a six-credit introductory course for school leader certification. Through analysis of a variety of qualitative data collected over nine semesters, I…

  3. Introducing Field-Based Geologic Research Using Soil Geomorphology

    Science.gov (United States)

    Eppes, Martha Cary

    2009-01-01

    A field-based study of soils and the factors that influence their development is a strong, broad introduction to geologic concepts and research. A course blueprint is detailed where students design and complete a semester-long field-based soil geomorphology project. Students are first taught basic soil concepts and to describe soil, sediment and…

  4. [The supervisor has a crucial role in the medical student's degree projects. Experiences from seven semesters at Karolinska Institutet].

    Science.gov (United States)

    Möller, Riitta; Shoshan, Maria; Ponzer, Sari

    2015-01-13

    In Sweden degree projects have a central role in evaluation of higher education, wherefore significant resources are spent on developing students' research competence. The undergraduate medical program at Karolinska Institutet introduced its degree project course in 2010. This paper gives an overview of the course and summarizes experiences from the first seven terms. In order to finalize their projects within one term, most students need substantial support. A highly structured course and frequent progress monitoring are advantageous. Other crucial factors are the quality of the supervision and students' verbal skills as well as support in scientific writing. In addition, increased awareness of the learning outcomes already at the beginning of the course may help students to achieve the expected results. Finally, students need to recognize their own responsibility for learning. 

  5. Nonequilibrium Chemical Effects in Single-Molecule SERS Revealed by Ab Initio Molecular Dynamics Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Sean A.; Apra, Edoardo; Govind, Niranjan; Hess, Wayne P.; El-Khoury, Patrick Z.

    2017-02-03

    Recent developments in nanophotonics have paved the way for achieving significant advances in the realm of single molecule chemical detection, imaging, and dynamics. In particular, surface-enhanced Raman scattering (SERS) is a powerful analytical technique that is now routinely used to identify the chemical identity of single molecules. Understanding how nanoscale physical and chemical processes affect single molecule SERS spectra and selection rules is a challenging task, and is still actively debated. Herein, we explore underappreciated chemical phenomena in ultrasensitive SERS. We observe a fluctuating excited electronic state manifold, governed by the conformational dynamics of a molecule (4,4’-dimercaptostilbene, DMS) interacting with a metallic cluster (Ag20). This affects our simulated single molecule SERS spectra; the time trajectories of a molecule interacting with its unique local environment dictates the relative intensities of the observable Raman-active vibrational states. Ab initio molecular dynamics of a model Ag20-DMS system are used to illustrate both concepts in light of recent experimental results.

  6. Authoring Multiple "Formas de ser": Three Bilingual Latino/a Fifth Graders Navigating School

    Science.gov (United States)

    Cuero, Kimberley K.

    2009-01-01

    Drawing from sociocultural and anthropological perspectives, I present 3 case examples of bilingual, Mexican-origin students enrolled in a transitional bilingual educational program in an urban elementary school. By using the theoretical constructs of figured worlds, authoring, and "formas de ser" (ways of being), I examine how student identities…

  7. DNA detection and single nucleotide mutation identification using SERS for molecular diagnostics and global health

    Science.gov (United States)

    Ngo, Hoan T.; Gandra, Naveen; Fales, Andrew M.; Taylor, Steve M.; Vo-Dinh, Tuan

    2017-02-01

    Nucleic acid-based molecular diagnostics at the point-of-care (POC) and in resource-limited settings is still a challenge. We present a sensitive yet simple DNA detection method with single nucleotide polymorphism (SNP) identification capability. The detection scheme involves sandwich hybridization of magnetic beads conjugated with capture probes, target sequences, and ultrabright surface-enhanced Raman Scattering (SERS) nanorattles conjugated with reporter probes. Upon hybridization, the sandwich probes are concentrated at the detection focus controlled by a magnetic system for SERS measurements. The ultrabright SERS nanorattles, consisting of a core and a shell with resonance Raman reporters loaded in the gap space between the core and the shell, serve as SERS tags for ultrasensitive signal detection. Specific DNA sequences of the malaria parasite Plasmodium falciparum and dengue virus 1 (DENV1) were used as the model marker system. Detection limit of approximately 100 attomoles was achieved. Single nucleotide polymorphism (SNP) discrimination of wild type malaria DNA and mutant malaria DNA, which confers resistance to artemisinin drugs, was also demonstrated. The results demonstrate the molecular diagnostic potential of the nanorattle-based method to both detect and genotype infectious pathogens. The method's simplicity makes it a suitable candidate for molecular diagnosis at the POC and in resource-limited settings.

  8. Using Ag-embedded TiO{sub 2} nanotubes array as recyclable SERS substrate

    Energy Technology Data Exchange (ETDEWEB)

    Ling, Yunhan, E-mail: yhling@mail.tsinghua.edu.cn [Lab of Advanced Materials, School of Materials Science & Engineering, Tsinghua University, Beijing 100084 (China); Zhuo, Yuqing; Huang, Liang [Lab of Advanced Materials, School of Materials Science & Engineering, Tsinghua University, Beijing 100084 (China); Mao, Duolu [School of Physical and Electronic Information Engineering, Qinghai Nationalities University, Xining, Qinghai 810007 (China)

    2016-12-01

    Highlights: • Ag embedded nanoparticles inside nanotube have better SERS enhancement than surface cap. • Ag NPs reconstruction via self-migration with UV and humidity control. • Self-cleaning effects both on organic molecule photo-oxidation as well as Ag ions photo-reduction. - Abstract: A simple strategy for synthesizing Ag-loaded TiO{sub 2} nanotube film for use as multifunctional photocatalyst and recyclable surface-enhanced Raman scattering (SERS) substrate is introduced. Highly aligned TiO{sub 2} nanotube arrays (TNTA) prepared via electrochemical anodization were used as a 3D rough host for silver nanoparticles. Ag deposits were sputtered in a vacuum, and it was found that their morphologies were mainly influenced by the diameters of nanotubes and the UV irradiation induced aging process, especially the self-migration of silver along the tubular wall. SERS and the self-cleaning effect were observed using Rhodamine 6G (R6G) as the probe molecule. The results showed that narrow nanotube and silver nanoparticles embedment contributed significantly to both the phenomenal SERS and recyclability.

  9. Fabrication of SERS Active Surface on Polyimide Sample by Excimer Laser Irradiation

    Directory of Open Access Journals (Sweden)

    T. Csizmadia

    2014-01-01

    Full Text Available A possible application of excimer laser irradiation for the preparation of surface enhanced Raman spectroscopy (SERS substrate is demonstrated. A polyimide foil of 125 μm thickness was irradiated by 240 pulses of focused ArF excimer laser beam (λ = 193 nm, FWHM = 20 ns. The applied fluence was varied between 40 and 80 mJ/cm2. After laser processing, the sample was coated with 40 nm silver by PLD in order to create a conducting layer required for the SERS application. The SERS activity of the samples was tested by Raman microscopy. The Raman spectra of Rhodamine 6G aqueous solution (c=10−3 mol/dm3 were collected from the patterned and metalized areas. For areas prepared at 40–60 mJ/cm2 laser fluences, the measured Raman intensities have shown a linear dependence on the applied laser fluence, while above 60 mJ/cm2 saturation was observed. The morphology of the SERS active surface areas was investigated by scanning electron microscopy. Finite element modeling was performed in order to simulate the laser-absorption induced heating of the polyimide foil. The simulation resulted in the temporal and spatial distribution of the estimated temperature in the irradiated polyimide sample, which are important for understanding the structure formation process.

  10. In situ SERS detection of emulsifiers at lipid interfaces using label-free amphiphilic gold nanoparticles.

    Science.gov (United States)

    Li, Yue; Driver, Michael; Winuprasith, Thunnalin; Zheng, Jinkai; McClements, David Julian; He, Lili

    2014-10-21

    Herein, we fabricated amphiphilic gold nanoparticles (GNPs) that can self-assemble at oil-water interfaces. We applied those GNPs for in situ SERS detection of emulsifier molecules within the interfacial region of oil in water (O/W) emulsion systems.

  11. Monitoring prion protein expression in complex biological samples by SERS for diagnostic applications

    Energy Technology Data Exchange (ETDEWEB)

    Manno, D; Filippo, E; Fiore, R; Serra, A [Dipartimento di Scienza dei Materiali, Universita del Salento, Lecce (Italy); Urso, E; Rizzello, A; Maffia, M [Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Universita del Salento, Lecce (Italy)

    2010-04-23

    Surface-enhanced Raman spectroscopy (SERS) allows a new insight into the analysis of cell physiology. In this work, the difficulty of producing suitable substrates that, besides permitting the amplification of the Raman signal, do not interact with the biological material causing alteration, has been overcome by a combined method of hydrothermal green synthesis and thermal annealing. The SERS analysis of the cell membrane has been performed with special attention to the cellular prion protein PrP{sup C}. In addition, SERS has also been used to reveal the prion protein-Cu(II) interaction in four different cell models (B104, SH-SY5Y, GN11, HeLa), expressing PrP{sup C} at different levels. A significant implication of the current work consists of the intriguing possibility of revealing and quantifying prion protein expression in complex biological samples by a cheap SERS-based method, replacing the expensive and time-consuming immuno-assay systems commonly employed.

  12. Circles within circles: crosstalk between protein Ser/Thr/Tyr-phosphorylation and Met oxidation

    Science.gov (United States)

    Background: Reversible posttranslational protein modifications such as phosphorylation of Ser/Thr/Tyr and Met oxidation are critical for both metabolic regulation and cellular signalling. Although these modifications are typically studied individually, herein we describe the potential for cross-talk...

  13. SERS-active ZnO/Ag hybrid WGM microcavity for ultrasensitive dopamine detection

    Science.gov (United States)

    Lu, Junfeng; Xu, Chunxiang; Nan, Haiyan; Zhu, Qiuxiang; Qin, Feifei; Manohari, A. Gowri; Wei, Ming; Zhu, Zhu; Shi, Zengliang; Ni, Zhenhua

    2016-08-01

    Dopamine (DA) is a potential neuro modulator in the brain which influences a variety of motivated behaviors and plays a key role in life science. A hybrid ZnO/Ag microcavity based on Whispering Gallery Mode (WGM) effect has been developed for ultrasensitive detection of dopamine. Utilizing this effect of structural cavity mode, a Raman signal of R6G (5 × 10-3 M) detected by this designed surface-enhanced Raman spectroscopy (SERS)-active substrate was enhanced more than 10-fold compared with that of ZnO film/Ag substrate. Also, this hybrid microcavity substrate manifests high SERS sensitivity to rhodamine 6 G and detection limit as low as 10-12 M to DA. The Localized Surface Plasmons of Ag nanoparticles and WGM-enhanced light-matter interaction mainly contribute to the high SERS sensitivity and help to achieve a lower detection limit. This designed SERS-active substrate based on the WGM effect has the potential for detecting neurotransmitters in life science.

  14. Using a silver-enhanced microarray sandwich structure to improve SERS sensitivity for protein detection.

    Science.gov (United States)

    Gu, Xuefang; Yan, Yuerong; Jiang, Guoqing; Adkins, Jason; Shi, Jian; Jiang, Guomin; Tian, Shu

    2014-03-01

    A simple and sensitive method, based on surface-enhanced Raman scattering (SERS), for immunoassay and label-free protein detection is reported. A series of bowl-shaped silver cavity arrays were fabricated by electrodeposition using a self-assembled polystyrene spheres template. The reflection spectra of these cavity arrays were recorded as a function of film thickness, and then correlated with SERS enhancement using sodium thiophenolate as the probe molecule. The results reveal that SERS enhancement can be maximized when the frequency of both the incident laser and the Raman scattering approach the frequency of the localized surface plasmon resonance. The optimized array was then used as the bottom layer of a silver nanoparticle-protein-bowl-shaped silver cavity array sandwich. The second layer of silver was introduced by the interactions between the proteins in the middle layer of the sandwich architecture and silver nanoparticles. Human IgG bound to the surface of this microcavity array can retain its recognition function. With the Raman reporter molecules labeled on the antibody, a detection limit down to 0.1 ng mL(-1) for human IgG is easily achieved. Furthermore, the SERS spectra of label-free proteins (catalase, cytochrome C, avidin and lysozyme) from the assembled sandwich have excellent reproducibility and high quality. The results reveal that the proposed approach has potential for use in qualitative and quantitative detection of biomolecules.

  15. SERS Substrates by the Assembly of Silver Nano cubes: High-Throughput and Enhancement Reliability Considerations

    International Nuclear Information System (INIS)

    Rabin, O.; Lee, S.Y.; Rabin, O.

    2012-01-01

    Small clusters of nanoparticles are ideal substrates for SERS measurements, but the SERS signal enhancement by a particular cluster is strongly dependent on its structural characteristics and the measurement conditions. Two methods for high-throughput assembly of silver nano cubes into small clusters at predetermined locations on a substrate are presented. These fabrication techniques make it possible to study both the structure and the plasmonic properties of hundreds of nanoparticle clusters. The variations in SERS enhancement factors from cluster to cluster were analyzed and correlated with cluster size and configuration, and laser frequency and polarization. Using Raman instruments with 633 nm and 785 nm lasers and linear clusters of nano cubes, an increase in the reproducibility of the enhancement and an increase in the average enhancement values were achieved by increasing the number of nano cubes in the cluster, up to 4 nano cubes per cluster. By examining the effect of cluster configuration, it is shown that linear clusters with nano cubes attached in a face-to-face configuration are not as effective SERS substrates as linear clusters in which nano cubes are attached along an edge

  16. Structure-dependent SERS activity of plasmonic nanorattles with built-in electromagnetic hotspots.

    Science.gov (United States)

    Liu, Keng-Ku; Tadepalli, Sirimuvva; Wang, Zheyu; Jiang, Qisheng; Singamaneni, Srikanth

    2017-11-20

    Hollow plasmonic nanostructures with built-in and accessible electromagnetic hotspots such as nanorattles, obtained through a galvanic replacement reaction, have received wide attention in chemical and biological sensing and targeted drug delivery. In this study, we investigate the surface enhanced Raman scattering (SERS) activity of plasmonic nanorattles obtained through different degrees of galvanic replacement of Au@Ag nanocubes. We found that the SERS efficacy of the nanorattles is governed by the plasmon extinction intensity, localized surface plasmon resonance (LSPR) wavelength of the nanostructures with respect to the excitation source and intensity of the electromagnetic field at the hotspot, with the latter playing a determining role. Finite-difference time-domain (FDTD) simulations showed excellent agreement with the experimental findings that an optimal degree of galvanic replacement is critical for maximum SERS enhancement. The rational design and synthesis of the plasmonic nanorattles based on these findings can make these nanostructures highly attractive for SERS-based chemical and biological sensing and bioimaging.

  17. Planar SERS nanostructures with stochastic silver ring morphology for biosensor chips

    DEFF Research Database (Denmark)

    Semenova, Anna; Goodilin, Eugene; Brazhe, Nadezda

    2012-01-01

    Surface-enhanced Raman spectroscopy (SERS) of living cells has rapidly become a powerful trend in biomedical diagnostics. It is a common belief that highly ordered, artificially engineered substrates are the best future decision in this field. This paper, however, describes an alternative...

  18. The Ser311Cys variation in the paraoxonase 2 gene increases the ...

    Indian Academy of Sciences (India)

    Supplementary data: The Ser311Cys variation in the paraoxonase 2 gene increases the risk of type 2 diabetes in northern Chinese. Yanchun Qu, Ze Yang, Feng Jin, Liang Sun, Chuanfang Zhang, Linong Ji, Hong Sun, Binyou Wang and Li Wang. J. Genet. 87, 165–169. Table 1. Clinical characteristics of case and control.

  19. Organelle-targeting surface-enhanced Raman scattering (SERS) nanosensors for subcellular pH sensing.

    Science.gov (United States)

    Shen, Yanting; Liang, Lijia; Zhang, Shuqin; Huang, Dianshuai; Zhang, Jing; Xu, Shuping; Liang, Chongyang; Xu, Weiqing

    2018-01-25

    The pH value of subcellular organelles in living cells is a significant parameter in the physiological activities of cells. Its abnormal fluctuations are commonly believed to be associated with cancers and other diseases. Herein, a series of surface-enhanced Raman scattering (SERS) nanosensors with high sensitivity and targeting function was prepared for the quantification and monitoring of pH values in mitochondria, nucleus, and lysosome. The nanosensors were composed of gold nanorods (AuNRs) functionalized with a pH-responsive molecule (4-mercaptopyridine, MPy) and peptides that could specifically deliver the AuNRs to the targeting subcellular organelles. The localization of our prepared nanoprobes in specific organelles was confirmed by super-high resolution fluorescence imaging and bio-transmission electron microscopy (TEM) methods. By the targeting ability, the pH values of the specific organelles can be determined by monitoring the vibrational spectral changes of MPy with different pH values. Compared to the cases of reported lysosome and cytoplasm SERS pH sensors, more accurate pH values of mitochondria and nucleus, which could be two additional intracellular tracers for subcellular microenvironments, were disclosed by this SERS approach, further improving the accuracy of discrimination of related diseases. Our sensitive SERS strategy can also be employed to explore crucial physiological and biological processes that are related to subcellular pH fluctuations.

  20. Sodium Chloride Crystal-Induced SERS Platform for Controlled Highly Sensitive Detection of Illicit Drugs.

    Science.gov (United States)

    Yu, Borong; Li, Pan; Zhou, Binbin; Tang, Xianghu; Li, Shaofei; Yang, Liangbao

    2018-04-03

    A sodium chloride crystal-driven spontaneous 'hot spot' structure was demonstrated as a SERS-active platform, to get reproducible SERS signals, and eliminate the need for mapping large areas, in comparison with solution phase testing. During the process of solvent evaporation, the crystals produced induced silver aggregates to assemble around themselves. The micro-scale crystals can also act as a template to obtain an optical position, such that the assembled hot area is conveniently located during SERS measurements. More importantly, the chloride ions added in colloids can also replace the citrate and on the surface of the silver sol, and further decrease the background interference. High quality SERS spectra from heroin, methamphetamine (MAMP), and cocaine have been obtained on the crystal-driven hot spot structure with high sensitivity and credible reproducibility. This approach can not only bring the nanoparticles to form plasmonic hot spots in a controlled way, and thus provide high sensitivity, but also potentially be explored as an active substrate for label-free detection of other illicit drugs or additives. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. [TLC-FT-SERS study on a pair of optic isomers in ephedra].

    Science.gov (United States)

    Wang, Yuan; Zhang, Jin-zhi; Ma, Xin-yong

    2004-11-01

    A new method for analyzing the ingredients of a pair of optic isomers in ephedra, nor-ephedrine and nor-pseudo-ephedrine, using hyphenated high-efficiency thin layer chromatography (TLC) and surface-enhanced Raman spectroscopy (SERS) techniques, is reported. The results show that the characteristic spectral bands of nor-ephedrine and nor-pseudo-ephedrine can be obtained from the TLC spot with 8 microg sample of about 2.0 mm in diameter. The difference between the SERS and solid spectra was found. Spectral bands at 1004 cm(-1) and 1605 cm(-1) were found greatly enhanced. Molecule was absorbed in surface silver sol by pi electrons in ring. Under similar experimental conditions the spectral information of Levo-nor-ephedrine ramifications TLC-SERS is rich with strong credibility, whereas dextral-nor-ephedrine ramifications show a relatively strong fluorescence backdrop with less spectral information and weak credibility. The effective combination of TLC and SERS can be used to analyse the chemical ingredients with high sensitivity.

  2. Hierarchical Nanogaps within Bioscaffold Arrays as a High-Performance SERS Substrate for Animal Virus Biosensing

    NARCIS (Netherlands)

    Shao, Feng; Lu, Zhicheng; Liu, Chen; Han, Heyou; Chen, Kun; Li, Wentao; He, Qigai; Peng, Hui; Chen, Juanni

    2014-01-01

    A three-dimensional (3D) biomimetic SERS substrate with hierarchical nanogaps was formed on the bioscaffold arrays of cicada wings by one-step and reagents-free ion-sputtering techniques. This approach requires a minimal fabrication effort and cost and offers Ag nanoislands and Ag nanoflowers with

  3. Efectividad del láser de baja intensidad en el control de la hipersensibilidad dentrinaria

    OpenAIRE

    Gomez, Nadia; Garcia, Karen; Herrera, Helen de; Herrera, Henry

    2008-01-01

    La hipersensibilidad dentinaria se define "un dolor breve y agudo que se origina en la dentina expuesta como respuesta a los estímulos típicos como los térmicos, evaporativos, táctiles, osmóticos o químicos que no pueden ser atribuidos a otra patología dental

  4. Phosphoproteome analysis of E-coli reveals evolutionary conservation of bacterial Ser/Thr/Tyr phosphorylation

    DEFF Research Database (Denmark)

    Macek, B.; Gnad, F.; Soufi, Boumediene

    2008-01-01

    Protein phosphorylation on serine, threonine, and tyrosine (Ser/Thr/Tyr) is generally considered the major regulatory posttranslational modification in eukaryotic cells. Increasing evidence at the genome and proteome level shows that this modification is also present and functional in prokaryotes...

  5. Rapid detection of salmonella using SERS with silver nano-substrate

    Science.gov (United States)

    Sundaram, J.; Park, B.; Hinton, A., Jr.; Windham, W. R.; Yoon, S. C.; Lawrence, K. C.

    2011-06-01

    Surface Enhanced Raman Scattering (SERS) can detect the pathogen in rapid and accurate. In SERS weak Raman scattering signals are enhanced by many orders of magnitude. In this study silver metal with biopolymer was used. Silver encapsulated biopolymer polyvinyl alcohol nano-colloid was prepared and deposited on stainless steel plate. This was used as metal substrate for SERS. Salmonella typhimurium a common food pathogen was selected for this study. Salmonella typhimurium bacteria cells were prepared in different concentrations in cfu/mL. Small amount of these cells were loaded on the metal substrate individually, scanned and spectra were recorded using confocal Raman microscope. The cells were exposed to laser diode at 785 nm excitation and object 50x was used to focus the laser light on the sample. Raman shifts were obtained from 400 to 2400 cm-1. Multivariate data analysis was carried to predict the concentration of unknown sample using its spectra. Concentration prediction gave an R2 of 0.93 and standard error of prediction of 0.21. The results showed that it could be possible to find out the Salmonella cells present in a low concentration in food samples using SERS.

  6. Derivatization reaction-based surface-enhanced Raman scattering (SERS) for detection of trace acetone.

    Science.gov (United States)

    Zheng, Ying; Chen, Zhuo; Zheng, Chengbin; Lee, Yong-Ill; Hou, Xiandeng; Wu, Li; Tian, Yunfei

    2016-08-01

    A facile method was developed for determination of trace volatile acetone by coupling a derivatization reaction to surface-enhanced Raman scattering (SERS). With iodide modified Ag nanoparticles (Ag IMNPs) as the SERS substrate, acetone without obvious Raman signal could be converted to SERS-sensitive species via a chemical derivatization reaction with 2,4-dinitrophenylhydrazine (2,4-DNPH). In addition, acetone can be effectively separated from liquid phase with a purge-sampling device and then any serious interference from sample matrices can be significantly reduced. The optimal conditions for the derivatization reaction and the SERS analysis were investigated in detail, and the selectivity and reproducibility of this method were also evaluated. Under the optimal conditions, the limit of detection (LOD) for acetone was 5mgL(-1) or 0.09mM (3σ). The relative standard deviation (RSD) for 80mgL(-1) acetone (n=9) was 1.7%. This method was successfully used for the determination of acetone in artificial urine and human urine samples with spiked recoveries ranging from 92% to 110%. The present method is convenient, sensitive, selective, reliable and suitable for analysis of trace acetone, and it could have a promising clinical application in early diabetes diagnosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. SERS and DFT study of p-hydroxybenzoic acid adsorbed on colloidal silver particles.

    Science.gov (United States)

    Chen, Y; Chen, S J; Li, S; Wei, J J

    2015-10-16

    In this study, normal Raman spectra of p—hydroxybenzoic acid (PHBA) powder and its surface—enhanced Raman scattering (SERS) spectra in silver colloidal solutions were measured under near infrared excitation conditions. In theoretical calculation, two models of PHBA adsorbed on the surfaces of silver nanoparticles were established. The Raman frequencies of these two models using density functional theory (DFT) method were calculated, and compared with the experimental results. It was found that the calculated Raman frequencies were in good agreement with experimental values, which indicates that there are two enhanced mechanism physical (electromagnetic, EM) enhancement and chemical (charge—transfer, CT) enhancement, in silver colloidal solutions regarding SERS effect. Furthermore, from high—quality SERS spectrum of PHBA obtained in silver colloids, we inferred that PHBA molecules in silver colloids adsorb onto the metal surfaces through carboxyl at a perpendicular orientation. The combination of SERS spectra and DFT calculation is thus useful for studies of the adsorption—orientation of a molecule on a metal colloid.

  8. Thin silica shell coated Ag assembled nanostructures for expanding generality of SERS analytes.

    Directory of Open Access Journals (Sweden)

    Myeong Geun Cha

    Full Text Available Surface-enhanced Raman scattering (SERS provides a unique non-destructive spectroscopic fingerprint for chemical detection. However, intrinsic differences in affinity of analyte molecules to metal surface hinder SERS as a universal quantitative detection tool for various analyte molecules simultaneously. This must be overcome while keeping close proximity of analyte molecules to the metal surface. Moreover, assembled metal nanoparticles (NPs structures might be beneficial for sensitive and reliable detection of chemicals than single NP structures. For this purpose, here we introduce thin silica-coated and assembled Ag NPs (SiO2@Ag@SiO2 NPs for simultaneous and quantitative detection of chemicals that have different intrinsic affinities to silver metal. These SiO2@Ag@SiO2 NPs could detect each SERS peak of aniline or 4-aminothiophenol (4-ATP from the mixture with limits of detection (LOD of 93 ppm and 54 ppb, respectively. E-field distribution based on interparticle distance was simulated using discrete dipole approximation (DDA calculation to gain insight into enhanced scattering of these thin silica coated Ag NP assemblies. These NPs were successfully applied to detect aniline in river water and tap water. Results suggest that SiO2@Ag@SiO2 NP-based SERS detection systems can be used as a simple and universal detection tool for environment pollutants and food safety.

  9. Metal Nanoparticles Deposited on Porous Silicon Templates as Novel Substrates for SERS

    Directory of Open Access Journals (Sweden)

    Lara Mikac

    2015-12-01

    Full Text Available In this paper, results on preparation of stable and uniform SERS solid substrates using macroporous silicon (pSi with deposited silver and gold are presented. Macroporous silicon is produced by anodisation of p-type silicon in hydrofluoric acid. The as prepared pSi is then used as a template for Ag and Au depositions. The noble metals were deposited in three different ways: by immersion in silver nitrate solution, by drop-casting silver colloidal solution and by pulsed laser ablation (PLA. Substrates obtained by different deposition processes were evaluated for SERS efficiency using methylene blue (MB and rhodamine 6G (R6G at 514.5, 633 and 785 nm. Using 514.5 nm excitation and R6G the limits of detection (LOD for macroporous Si samples with noble metal nanostructures obtained by immersion of pSi sample in silver nitrate solution and by applying silver colloidal solution to pSi template were 10–9 M and 10–8 M respectively. Using 633 nm laser and MB the most noticeable SERS activity gave pSi samples ablated with 30000 and 45000 laser pulses where the LODs of 10–10 M were obtained. The detection limit of 10–10 M was also reached for 4 mA cm–2-15 min pSi sample, silver ablated with 30000 pulses. Macroporous silicon proved to be a good base for the preparation of SERS substrates.

  10. O ser humano da sociedade capitalista na concepção de Erich Fromm

    Directory of Open Access Journals (Sweden)

    Edmilson Ferreira Marques

    2010-07-01

    Full Text Available

    A proposta deste texto é buscar na psicanálise pensada e desenvolvida por Erich Fromm elementos para se pensar o ser humano da sociedade capitalista. Erich Fromm, dentre a maioria dos psicanalistas existentes, desde Freud, procurou desenvolver suas pesquisas e reflexões a partir da “psicanálise humanista”, oferecendo, assim, recursos heurísticos fundamentais para se pensar a vida na sociedade. Nesse sentido, propomos analisar primeiramente o seu método de análise, a partir do qual acreditamos ser fundamental para compreender o procedimento teórico/metodológico que utilizava para pensar os temas por ele abordados, e, nesse sentido, encontrar o caminho a ser percorrido na busca em seu pensamento da seguinte questão: como abordar a partir de seu ponto de vista, o ser humano da sociedade capitalista? Enfim, propomos uma avaliação da própria teoria de Fromm, apontando suas principais contribuições.

  11. Complete urinary tract infection (UTI) diagnosis and antibiogram using surface enhanced Raman spectroscopy (SERS)

    Science.gov (United States)

    Hadjigeorgiou, Katerina; Kastanos, Evdokia; Kyriakides, Alexandros; Pitris, Costas

    2012-03-01

    There are three stages to a complete UTI diagnosis: (1) identification of a urine sample as positive/negative for an infection, (2) identification of the responsible bacterium, (3) antibiogram to determine the antibiotic to which the bacteria are most sensitive to. Using conventional methods, all three stages require bacterial cultures in order to provide results. This long delay in diagnosis causes a rise in ineffective treatments, chronic infections, health care costs and antibiotic resistance. In this work, SERS is used to identify a sample as positive/negative for a UTI as well as to obtain an antibiogram against different antibiotics. SERS spectra of serial dilutions of E. coli bacteria mixed with silver nanoparticles, showed a linear correlation between spectral intensity and concentration. For antibiotic sensitivity testing, SERS spectra of three species of gram negative bacteria were collected four hours after exposure to the antibiotics ciprofloxacin and amoxicillin. Spectral analysis revealed clear separation between bacterial samples exposed to antibiotics to which they were sensitive and samples exposed to antibiotics to which they were resistant. With the enhancement provided by SERS, the technique can be applied directly to urine samples leading to the development of a new, rapid method for UTI diagnosis and antibiogram.

  12. Use of clinical practice as a motivating tool of radioprotection teaching and radiopharmacology in early semesters of pharmacy course

    International Nuclear Information System (INIS)

    Andrighetto, Daniela; Lüdke, Everton

    2014-01-01

    The research teaching methods aimed at the success of the higher education student in pharmacology and medicine courses in technical expertise in the fields of radiological protection, radiopharmacology and interventional radiology is extremely important in view of the progress of these sectors. The objective of this work is to propose a methodological sequence of teaching work with first-year students of pharmacy and medicine courses within a biophysical discipline where the integrated knowledge to clinical practice can be used for this purpose. The methodology was to assess individual learning of a group of N = 49 students of the first half in the age group of 17-19 years through conceptual acquisition by the traditional method of 'blackboard and chalk' and developed method that includes four pedagogical moments focused on the area health. An analysis of the evaluation student performance through Variance Analysis of a pathway showed improved scores with respect to the performance of application issues of knowledge concerning radiation protection and biological mechanisms of radiation with respect to the method of 'blackboard and chalk' with p < 0.05. Therefore, work with students with respect to the content in the form of six steps of clinical interest are a promising technique for radiation protection education in the early grades of college courses with experimental effectiveness

  13. Label-free direct surface-enhanced Raman scattering (SERS) of nucleic acids (Conference Presentation)

    Science.gov (United States)

    Guerrini, Luca; Morla-Folch, Judit; Gisbert-Quilis, Patricia; Xie, Hainan; Alvarez-Puebla, Ramon

    2016-03-01

    Recently, plasmonic-based biosensing has experienced an unprecedented level of attention, with a particular focus on the nucleic acid detection, offering efficient solutions to engineer simple, fast, highly sensitive sensing platforms while overcoming important limitations of PCR and microarray techniques. In the broad field of plasmonics, surface-enhanced Raman scattering (SERS) spectroscopy has arisen as a powerful analytical tool for detection and structural characterization of biomolecules. Today applications of SERS to nucleic acid analysis largely rely on indirect strategies, which have been demonstrated very effective for pure sensing purposes but completely dismiss the exquisite structural information provided by the direct acquisition of the biomolecular vibrational fingerprint. Contrarily, direct label-free SERS of nucleic acid shows an outstanding potential in terms of chemical-specific information which, however, remained largely unexpressed mainly because of the inherent poor spectral reproducibility and/or limited sensitivity. To address these limitations, we developed a fast and affordable high-throughput screening direct SERS method for gaining detailed genomic information on nucleic acids (DNA and RNA) and for the characterization and quantitative recognition of DNA interactions with exogenous agents. The simple strategy relies on the electrostatic adhesion of DNA/RNA onto positively-charged silver colloids that promotes the nanoparticle aggregation into stable clusters yielding intense and reproducible SERS spectra at picogram level (i.e. the analysis can be performed without the necessity of amplification steps thus providing realistic direct information of the nucleic acid in its native state). We anticipate this method to gain a vast impact and set of applications in different fields, including medical diagnostics, genomic screening, drug discovery, forensic science and even molecular electronics.

  14. Improved size-tunable synthesis and SERS properties of Au nanostars

    Science.gov (United States)

    Khlebtsov, Boris; Panfilova, Elizaveta; Khanadeev, Vitaly; Khlebtsov, Nikolai

    2014-10-01

    Multibranched Au nanoparticles with sharp tips (commonly called nanostars, NSTs) have attracted significant attention as bright scattering labels, photothermal transducers, nanocarriers, and surface-enhanced Raman scattering (SERS) tags. However, for surfactant-free synthesized NSTs, the existing data on the size tuning and the relation between the size of NSTs and their SERS efficiency still remain limited. Here, we address these questions by synthesizing and comparing SERS for surfactant-free NSTs of different sizes and plasmon resonance (PR) wavelengths. The NSTs were fabricated by seeded growth through a two-step surfactant-free approach in which quasispherical seeds were overgrown via reduction of added Au by ascorbic acid in the presence of Ag ions. By varying the seed size from 3 to 35 nm, we tuned the final NST size from 45 to 150 nm while retaining the star-like morphology with sharp tips and ensuring PR tunability from 630 to 900 nm. The NST size and PR limits can be expanded from 40 to 200 nm and from 600 to 930 nm, respectively, by simultaneous variation in the seed size and concentration. The SERS efficiency of the fabricated NSTs was examined by Raman measurements of 1,4-aminothiophenol (ATP) adsorbed on the surface of colloidal NST particles. Although the homogenous analytical enhancement factor (AEF) did not depend essentially on the NST size and varied from 4 × 106 to 107, the enhancing properties of single-particle NST tags were strongly size-dependent. Specifically, the AEF for 150-nm NST35-ATP complexes was 30 and 100 times greater than that for 70-nm NST15-ATP and 45-nm NST3-ATP complexes, respectively. These properties make the NST-ATP complex a prospective platform for SERS imaging.

  15. O cotidiano do ser-adolescendo com aids: movimento ou momento existencial?

    Directory of Open Access Journals (Sweden)

    Cristiane Cardoso de Paula

    Full Text Available As crianças com AIDS por transmissão vertical transitam da infância para adolescência, e pouco se sabe sobre como cuidam de si. Compreender este cotidiano do adolescer foi o objetivo desta investigação fenomenológica com análise hermenêutica heideggeriana. A entrevista com 11 meninos/meninas (12-14 anos não institucionalizados, que conheciam seu diagnóstico, ocorreu depois da aprovação do projeto pelo Comitê de Ética de três instituições do Rio de Janeiro, cenários da pesquisa. Os resultados apontaram um cotidiano marcado pelos momentos infância e adolescência. Às vezes quer voltar a ser-criança para brincar; se re-conhece como ser-adolescente pela aparência, humor, atividades diárias, lazer e relacionamentos. Transitando entre esses momentos, re-vela-se como ser-adolescendo. Neste movimento existencial des-vela-se como ser-de-possibilidades, que não está limitado à dupla-facticidade: adolescer (segundo demarcações etárias e características predeterminadas e AIDS (fragilidade clínica. Portanto, conjugar as dimensões biológica e existencial, no modelo assistencial-institucional, é o desafio do cuidado ao ser-adolescendo.

  16. Why Ser and not Thr brokers catalysis in the trypsin fold.

    Science.gov (United States)

    Pelc, Leslie A; Chen, Zhiwei; Gohara, David W; Vogt, Austin D; Pozzi, Nicola; Di Cera, Enrico

    2015-02-24

    Although Thr is equally represented as Ser in the human genome and as a nucleophile is as good as Ser, it is never found in the active site of the large family of trypsin-like proteases that utilize the Asp/His/Ser triad. The molecular basis of the preference of Ser over Thr in the trypsin fold was investigated with X-ray structures of the thrombin mutant S195T free and bound to an irreversible active site inhibitor. In the free form, the methyl group of T195 is oriented toward the incoming substrate in a conformation seemingly incompatible with productive binding. In the bound form, the side chain of T195 is reoriented for efficient substrate acylation without causing steric clash within the active site. Rapid kinetics prove that this change is due to selection of an active conformation from a preexisting ensemble of reactive and unreactive rotamers whose relative distribution determines the level of activity of the protease. Consistent with these observations, the S195T substitution is associated with a weak yet finite activity that allows identification of an unanticipated important role for S195 as the end point of allosteric transduction in the trypsin fold. The S195T mutation abrogates the Na(+)-dependent enhancement of catalytic activity in thrombin, activated protein C, and factor Xa and significantly weakens the physiologically important allosteric effects of thrombomodulin on thrombin and of cofactor Va on factor Xa. The evolutionary selection of Ser over Thr in trypsin-like proteases was therefore driven by the need for high catalytic activity and efficient allosteric regulation.

  17. PENERAPAN K-OPTIMAL PADA ALGORITMA KNN UNTUK PREDIKSI KELULUSAN TEPAT WAKTU MAHASISWA PROGRAM STUDI ILMU KOMPUTER FMIPA UNLAM BERDASARKAN IP SAMPAI DENGAN SEMESTER 4

    Directory of Open Access Journals (Sweden)

    Mutiara Ayu Banjarsari

    2016-04-01

    Full Text Available The data pile on a database of academic information systems at Computer Science Program of Mathematic and Natural Science Faculty of Lambung Mangkurat University is not fully utilized, although it can provide new information that has not been known before. Data mining techniques can be used to predict the timely graduation of students. The k-Nearest Nieghbor, a method to classify objects based on training data located closest to the object, was used in this study. Selection of the value of k in kNN algorithm became important because it would affect the performance of the algorithm kNN, therefore it was necessary to know how the value of k and the level of accuracy. The k-Fold Cross Validation method and Accuracy Test was used to determine the value of k-Optimal. The result showed that the value of k = 5 was defined as k-Optimal which was then be applied in the kNN algorithm for prediction of timely graduation of students based on the Grade Point Average up to 4th semester. Keywords: kNN, k-Optimal, Classification, Data mining, k-Fold Cross Validation method Tumpukan data pada database sistem informasi akademik Program Studi Ilmu Komputer FMIPA Unlam belum dimanfaatkan secara maksimal, padahal dari data tersebut dapat memberikan sebuah informasi baru yang belum diketahui sebelumnya. Teknik data mining dapat digunakan untuk memprediksi kelulusan tepat waktu mahasiswa. Penelitian menggunakan metode k-Nearest Nieghbor yang merupakan sebuah metode untuk melakukan klasifikasi terhadap objek berdasarkan data training yang jaraknya paling dekat dengan objek tersebut. Pemilihan nilai k pada algoritma kNN menjadi hal yang penting karena akan mempengaruhi kinerja dari algoritma kNN, oleh karena itu perlu diketahui berapa nilai k dan tingkat akurasinya. Metode k-Fold Cross Validation dan Uji Akurasi digunakan untuk mengetahui nilai k-Optimal. Hasil yang didapat adalah nilai k=5 dengan tingkat akurasi sebesar 80.00% yang ditetapkan sebagai k-Optimal. Nilai k

  18. The Use and Evaluation of Scaffolding, Student Centered-Learning, Behaviorism, and Constructivism to Teach Nuclear Magnetic Resonance and IR Spectroscopy in a Two-Semester Organic Chemistry Course

    Science.gov (United States)

    Livengood, Kimberly; Lewallen, Denver W.; Leatherman, Jennifer; Maxwell, Janet L.

    2012-01-01

    Since 2002, infrared spectroscopy (IR) and nuclear magnetic resonance (NMR) spectrometry have been introduced at the beginning of the first-semester organic chemistry lab course at this university. Starting in 2008, each individual student was given 20 unique homework problems that consisted of multiple-choice [superscript 1]H NMR and IR problems…

  19. The BARD1 Cys557Ser variant and breast cancer risk in Iceland.

    Directory of Open Access Journals (Sweden)

    Simon N Stacey

    2006-07-01

    Full Text Available Most, if not all, of the cellular functions of the BRCA1 protein are mediated through heterodimeric complexes composed of BRCA1 and a related protein, BARD1. Some breast-cancer-associated BRCA1 missense mutations disrupt the function of the BRCA1/BARD1 complex. It is therefore pertinent to determine whether variants of BARD1 confer susceptibility to breast cancer. Recently, a missense BARD1 variant, Cys557Ser, was reported to be at increased frequencies in breast cancer families. We investigated the role of the BARD1 Cys557Ser variant in a population-based cohort of 1,090 Icelandic patients with invasive breast cancer and 703 controls. We then used a computerized genealogy of the Icelandic population to study the relationships between the Cys557Ser variant and familial clustering of breast cancer.The Cys557Ser allele was present at a frequency of 0.028 in patients with invasive breast cancer and 0.016 in controls (odds ratio [OR] = 1.82, 95% confidence interval [CI] 1.11-3.01, p = 0.014. The alleleic frequency was 0.037 in a high-predisposition group of cases defined by having a family history of breast cancer, early onset of breast cancer, or multiple primary breast cancers (OR = 2.41, 95% CI 1.22-4.75, p = 0.015. Carriers of the common Icelandic BRCA2 999del5 mutation were found to have their risk of breast cancer further increased if they also carried the BARD1 variant: the frequency of the BARD1 variant allele was 0.047 (OR = 3.11, 95% CI 1.16-8.40, p = 0.046 in 999del5 carriers with breast cancer. This suggests that the lifetime probability of a BARD1 Cys557Ser/BRCA2 999del5 double carrier developing breast cancer could approach certainty. Cys557Ser carriers, with or without the BRCA2 mutation, had an increased risk of subsequent primary breast tumors after the first breast cancer diagnosis compared to non-carriers. Lobular and medullary breast carcinomas were overrepresented amongst Cys557Ser carriers. We found that an excess of ancestors

  20. Researching research

    DEFF Research Database (Denmark)

    Pais, Alexandre; Valero, Paola

    2012-01-01

    We discuss contemporary theories in mathematics education in order to do research on research. Our strategy consists of analysing discursively and ideologically recent key publications addressing the role of theory in mathematics education research. We examine how the field fabricates its object...... of research by deploying Foucault’s notion of bio-politics - mainly to address the object “learning” - and Žižek’s ideology critique - to address the object “mathematics”. These theories, which have already been used in the field to research teaching and learning, have a great potential to contribute...... to a reflexivity of research on its discourses and effects. Furthermore, they enable us to present a clear distinction between what has been called the sociopolitical turn in mathematics education research and what we call a positioning of mathematics education (research) practices in the Political....