WorldWideScience

Sample records for gold humanism honor

  1. Interdisciplinary Teaching of Theatre and Human Rights in Honors

    Science.gov (United States)

    Szasz, Maria

    2017-01-01

    Since spring 2012, the author has taught a 300-level Theatre and Human Rights class in the University of New Mexico Honors College. One of the centerpieces of honors education is careful research and thorough analysis of what is taught and why it is taught. In creating the honors class Theatre and Human Rights, the author explored how she would…

  2. Honors

    Science.gov (United States)

    Anonymous

    2012-05-01

    A number of AGU members were honored during the European Geosciences Union's (EGU) General Assembly, held on 22-27 April in Vienna. EGU Union awards were presented to the following people: Vincent Courtillot, University of Paris Diderot, France, received the 2012 Arthur Holmes Medal and EGU honorary membership for seminal contributions to geomagnetism and the geodynamics of mantle hot spots.Michael Ghil, University of California, Los Angeles, and École Normale Supérieure, France, received the 2012 Alfred Wegener Medal and EGU honorary membership for his leading contributions to theoretical climate dynamics; his innovative observational studies involving model assimilation of satellite data in meteorology, oceanography, and space physics; the breadth of his interdisciplinary studies, including macroeconomics; and his extensive supervision and mentoring of scores of graduate and postdoctoral students. Robin Clarke, Universidade Federal do Rio Grande do Sul, Brazil, received the 2012 Alexander von Humboldt Medal for fundamental contributions in statistical analysis and modeling of hydrological processes.Angioletta Coradini, Istituto Nazionale di Astrofsica, Italy, received the 2012 Jean Dominique Cassini Medal and EGU honorary membership in recognition of her important and wide range of work in planetary sciences and solar system formation and for her leading role in the development of space infrared instrumentation for planetary exploration.

  3. Honors

    Science.gov (United States)

    2011-10-01

    More than a dozen AGU members are among 94 researchers announced by U.S. president Barack Obama on 26 September as recipients of the Presidential Early Career Award for Scientists and Engineers. The award, which is coordinated by the Office of Science and Technology Policy within the Executive Office of the President, is considered the highest honor bestowed by the U.S. government on science and engineering professionals in the early stages of their independent research careers. This year's recipients include Jeffrey Book, Naval Research Laboratory; Jonathan Cirtain, NASA Marshall Space Flight Center; Fotini Katopodes Chow, University of California, Berkeley; Elizabeth Cochran, U.S. Geological Survey (USGS); Ian Howat, Ohio State University; Christiane Jablonowski, University of Michigan; Justin Kasper, Smithsonian Astrophysical Observatory; Elena Litchman, Michigan State University; James A. Morris Jr., National Oceanic and Atmospheric Administration (NOAA); Erin M. Oleson, NOAA; Victoria Orphan, California Institute of Technology; Sasha Reed, USGS; David Shelly, USGS; and Feng Wang, University of California, Berkeley. Five AGU members are among 10 U.S. representatives recently selected for International Arctic Science Committee working groups. The AGU members, chosen as representatives through the U.S. National Academies review process, are Atmosphere Working Group member James Overland, Pacific Marine Environmental Laboratory, NOAA; Cryosphere Working Group members Walter Meier, University of Colorado at Boulder, and Elizabeth Hunke, Los Alamos National Laboratory; Marine Working Group member Mary-Louise Timmermans, Yale University; and Terrestrial Working Group member Vanessa Lougheed, University of Texas at El Paso.

  4. Honors and the Humanities: Necessary as Air and Water

    Science.gov (United States)

    Salas, Angela Marie

    2015-01-01

    In a cultural environment that maintains that post-secondary education ought to produce job ready graduates, the importance of the liberal arts and the competencies they teach, along with the questions they engage, often comes up for debate. In such a culture, honors may appear frivolous, elitist, and rear-guard. Angela Marie Salas defends both…

  5. A course for developing interprofessional skills in pre-professional honor students using humanities and media.

    Science.gov (United States)

    Poirier, Therese I; Stamper-Carr, Connie; Newman, Kate

    2017-09-01

    To design and implement an undergraduate honors course for pre-health professional students that develops interpersonal skills through use of a variety of humanities. A three credit hour course in an honors seminar sequence was developed by pharmacy practice faculty and with input from faculty in mass communications, philosophy, applied communication studies and history. The course utilized a variety of media such as literature, film, and podcasts to foster student discussion about a variety of health-related topics. Topics included public health, stigmatization, portrayals of health care providers, patient experiences, health care ethics, aging, and death and dying. Students were assessed using pre-class assignments and reflective writings as well as a formal written and oral presentation on a selected health-related book. A quasi-experimental design was used to assess the impact of the course on desired course outcomes. The first course offering was to 22 undergraduate pre-health professional honors students. Pre- and post-course surveys on students' perceptions and students' reflective writings revealed achievement of desired course outcomes. Post-course evaluations also revealed positive perceptions about the course. The design of this course provided an outlet for students to read and enjoy various forms of media, while also meeting its goal of exposing students to a variety of humanities. The course allowed students to think critically about various health care issues, and to begin to develop interpersonal skills. The course could be adapted for pharmacy by developing affective domains of the Accreditation Council for Pharmacy Education (ACPE) Standards. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. The CHROME Honors Program

    Science.gov (United States)

    Wilson, Eleanor

    2002-01-01

    The CHROME Honors Program was designed as a two-week residential program for 9th and 1Oth grade students participating in CHROME clubs. The curriculum focused on the health sciences with instruction from: (1) the science and health curriculum of the Dozoretz National Program for Minorities in Applied Sciences (DNIMAS) Program of Norfolk State University (NSU); (2) the humanities curriculum of the NSU Honors Program; (3) NASA-related curriculum in human physiology. An Advisory Committee was formed to work with the Project Coordinator in the design of the summer program.

  7. 2016 High School Honors Human Anatomy and Physiology Curriculum Investigation for College Board Advanced Placement Classification Validity

    Directory of Open Access Journals (Sweden)

    Jeanine Siebold

    2017-02-01

    Full Text Available Four sections of senior Honors Human Anatomy and Physiology (A&P students are representative of sixty-five nations. These classes participated in a yearlong investigation pursuant of innovative learning, and grading modalities to introduce a 21st century curriculum for A&P to become a College Board Advanced Placement (AP course. All enrollees began the year by taking a self-assessment based on Howard Gardner's Multiple Intelligences. This data was evaluated for the design of learning approaches identifying student uniqueness that could better implement the Next Generation Science Standards (NGSS, and present State of Tennessee Human Anatomy and Physiology Learning Standards laying the groundwork to write the AP curriculum. Component curriculum rubrics were used, and modified to enable students to self-evaluate their performance in certain areas. Students participated in teams represented as Center for Disease Control and Prevention (CDC 'Intern Teams' investigating various diseases. The students, also, researched health equity, and disparity issues from variables based on survey questions they designed that could affect the health care treatment of patients suffering from their investigated disease. They then proposed a 2016 CDC Educational Campaign revamping public health education for the disease, including brochure, and public service announcement (PSA.

  8. 14 CFR Appendix A to Part 1221 - Congressional Space Medal of Honor

    Science.gov (United States)

    2010-01-01

    ...—Congressional Space Medal of Honor Obverse description A circular green enamel wreath of laurel surmounted by a.... cable nos. of colors Gold 65021 (old gold). Dark Blue 70076 (independence blue). Blue 65014 (light blue...

  9. Uptake of gold nanoparticles in primary human endothelial cells

    DEFF Research Database (Denmark)

    Klingberg, Henrik; Oddershede, Lene B.; Löschner, Katrin

    2015-01-01

    Gold nanoparticles (AuNPs) are relevant in nanomedicine for drug delivery in the vascular system, where endothelial cells are the first point of contact. We investigated the uptake of 80 nm AuNPs in primary human umbilical vein endothelial cells (HUVECs) by flow cytometry, 3D confocal microscopy....... Uptake of AuNPs in HUVECs occurred mainly by clathrin-mediated endocytosis and trafficking to membrane enclosures in the form of single particles and agglomerates of 2–3 particles....

  10. Housing Honors. National Collegiate Honors Council Monograph Series

    Science.gov (United States)

    Frost, Linda, Ed.; Kay, Lisa W., Ed.; Poe, Rachael, Ed.

    2015-01-01

    Honors administrators spend much of their time explaining and describing what honors is and does. When they talk about what honors looks like nationally, they should have answers to the following important questions: How pervasive is the model of separate honors facilities?; How pervasive are the legendary closets that honors programs have so…

  11. Mercury hazards from gold mining to humans, plants, and animals

    Science.gov (United States)

    Eisler, R.

    2004-01-01

    Mercury contamination of the environment from historical and ongoing mining practices that rely on mercury amalgamation for gold extraction is widespread. Contamination was particularly severe in the immediate vicinity of gold extraction and refining operations; however, mercury--especially in the form of water-soluble methylmercury--may be transported to pristine areas by rainwater, water currents, deforestation, volatilization, and other vectors. Examples of gold mining-associated mercury pollution are shown for Canada, the United States, Africa, China, the Philippines, Siberia, and South America. In parts of Brazil, for example, mercury concentrations in all abiotic materials, plants, and animals--including endangered species of mammals and reptiles--collected near ongoing mercury-amalgamation gold mining sites were far in excess of allowable mercury levels promulgated by regulatory agencies for the protection of human health and natural resources. Although health authorities in Brazil are unable to detect conclusive evidence of human mercury intoxication, the potential exists in the absence of mitigation for epidemic mercury poisoning of the mining population and environs. In the United States, environmental mercury contamination is mostly from historical gold mining practices, and portions of Nevada remain sufficiently mercury-contaminated to pose a hazard to reproduction of carnivorous fishes and fish-eating birds. Concentrations of total mercury lethal to sensitive representative natural resources range from 0.1 to 2.0 ug/L of medium for aquatic organisms; from 2200 to 31,000 ug/kg body weight (acute oral) and 4000 to 40,000 ug/kg (dietary) for birds; and from 100 to 500 ug/kg body weight (daily dose) and 1000 to 5000 ug/kg diet for mammals. Significant adverse sublethal effects were observed among selected aquatic species at water concentrations of 0.03 to 0.1 ug Hg/L. For some birds, adverse effects--mainly on reproduction--have been associated with total

  12. Determination of gold accumulation in human tissues caused by gold therapy using x-ray fluorescence analysis

    International Nuclear Information System (INIS)

    Bacso, J.; Uzonyi, I.; Dezsoe, B.

    1986-08-01

    Human autopsy tissues from five patients with rheumatoid arthritis treated earlier with aqueous solution of gold and those from untreated control with the same disease were analyzed by x-ray fluorescence spectrometry using a conventional Si(Li) detection system. The gold and zinc concentrations of tissues were determined and compared with literature data. Correlation was found between Zn and Au concentrations in heart, lung, kidney and liver tissues. (author)

  13. Human serum albumin mediated self-assembly of gold nanoparticles into hollow spheres

    International Nuclear Information System (INIS)

    Nayak, Nimai C; Shin, Kwanwoo

    2008-01-01

    The assembly of nanoparticles in topologically predefined superstructures is an important area in nanoscale architecture. In this paper, we report an unusual aggregation phenomenon involving L-lysine capped gold nanoparticles and human serum albumin into hollow nanospheres. The electrostatic interaction between positively charged L-lysine capped gold nanoparticles and negatively charged human serum albumin at physiological pH led to the assembly of the gold nanoparticles into hollow spheres. The phenomenon can be explained by the dry hole opening mechanism

  14. Synthesis and characterization of human transferrin-stabilized gold nanoclusters

    Energy Technology Data Exchange (ETDEWEB)

    Le Guevel, Xavier; Schneider, Marc [Pharmaceutical Nanotechnology, Saarland University, Saarbruecken (Germany); Daum, Nicole, E-mail: Marc.Schneider@mx.uni-saarland.de [Drug Delivery, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Saarbruecken (Germany)

    2011-07-08

    Human transferrin has been biolabelled with gold nanoclusters (Au NCs) using a simple, fast and non-toxic method. These nanocrystals (<2 nm) are stabilized in the protein via sulfur groups and have a high fluorescence emission in the near infrared region (QY = 4.3%; {lambda}{sub em} = 695 nm). Structural investigation and photophysical measurements show a high population of clusters formed of 22-33 gold atoms covalently bound to the transferrin. In solutions with pH ranging from 5 to 10 and in buffer solutions (PBS, HEPES), those biolabelled proteins exhibit a good stability. No significant quenching effect of the fluorescent transferrin has been detected after iron loading of iron-free transferrin (apoTf) and in the presence of a specific polyclonal antibody. Additionally, antibody-induced agglomeration demonstrates no alteration in the protein activity and the receptor target ability. MTT and Vialight Plus tests show no cytotoxicity of these labelled proteins in cells (1 {mu}g ml{sup -1}-1 mg ml{sup -1}). Cell line experiments (A549) indicate also an uptake of the iron loaded fluorescent proteins inside cells. These remarkable data highlight the potential of a new type of non-toxic fluorescent transferrin for imaging and targeting.

  15. HONOR, ANGER, AND BELITTLEMENT IN ARISTOTLE’S ETHICS

    OpenAIRE

    Robert Sokolowski

    2014-01-01

    The author considers the phenomenon of honor (timē) by examining Aristotle’s description of it and its role in ethical and political life. His study of honor leads him to two related phenomena, anger (orgē) and belittlement or contempt (oligōria); examining them helps him define honor more precisely. With his examination of honor the author shows how densely interwoven Aristotle’s ethical theory is; he illuminates such diverse things as the human good, political life and friendship, virtue, v...

  16. Human sulfite oxidase electrochemistry on gold nanoparticles modified electrode.

    Science.gov (United States)

    Frasca, Stefano; Rojas, Oscar; Salewski, Johannes; Neumann, Bettina; Stiba, Konstanze; Weidinger, Inez M; Tiersch, Brigitte; Leimkühler, Silke; Koetz, Joachim; Wollenberger, Ulla

    2012-10-01

    The present study reports a facile approach for sulfite biosensing, based on enhanced direct electron transfer of a human sulfite oxidase (hSO) immobilized on a gold nanoparticles modified electrode. The spherical core shell AuNPs were prepared via a new method by reduction of HAuCl(4) with branched poly(ethyleneimine) in an ionic liquids resulting particles with a diameter less than 10nm. These nanoparticles were covalently attached to a mercaptoundecanoic acid modified Au-electrode where then hSO was adsorbed and an enhanced interfacial electron transfer and electrocatalysis was achieved. UV/Vis and resonance Raman spectroscopy, in combination with direct protein voltammetry, are employed for the characterization of the system and reveal no perturbation of the structural integrity of the redox protein. The proposed biosensor exhibited a quick steady-state current response, within 2 s, a linear detection range between 0.5 and 5.4 μM with a high sensitivity (1.85 nA μM(-1)). The investigated system provides remarkable advantages in the possibility to work at low applied potential and at very high ionic strength. Therefore these properties could make the proposed system useful in the development of bioelectronic devices and its application in real samples. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Orchestral Stalls, Honore Daumier

    Science.gov (United States)

    Lucero-Criswell, Amber

    2004-01-01

    Honore Daumier is probably best known as a politically motivated artist. Born in Marseilles in 1808, the French artist lived through one of the most turbulent eras of his country's history. With his artistic prowess and biting wit, he recorded the 1848 revolution, the rise and fall of the Second Empire, the Crimean and Franco-Prussian Wars, and…

  18. Honoring the Elders.

    Science.gov (United States)

    Yazzie, Evangeline Parsons; St. Clair, Robert N.

    The co-directors of the 1998 Annual Symposium for Language Renewal and Revitalization describe how they came up with a focus and presenters for the symposium. They began by discussing their concern over the loss of indigenous languages and cultures, then decided to honor tribal elders by choosing one to represent them all as the symposium's…

  19. Veterinary medicine professor receives national honor

    OpenAIRE

    Douglas, Jeffrey S.

    2005-01-01

    Marie-Suthers-McCabe, of Riner, Va., associate professor of small animal clinical sciences at the Virginia-Maryland Regional College of Veterinary Medicine, has been awarded the highest honor in the nation for work in the area of the "human/animal bond."

  20. Honoring our Nation's Veterans

    Directory of Open Access Journals (Sweden)

    Robbins RA

    2015-11-01

    Full Text Available No abstract available. Article truncated at 150 words. Today is Armistice Day, renamed Veterans Day in 1954, to honor our Nation's Veterans. In Washington the rhetoric from both the political right and left supports our Veterans. My cynical side reminds me that this might have something to do with Veterans voting in a higher percentage than the population as a whole, but let me give the politicians this one. Serving our Country in the military is something that deserves to be honored. I was proud to serve our Veterans over 30 years at the four Department of Veterans Affairs (VA hospitals. However, the VA has had a very bad year. First, in Washington there were the resignations of the Secretary of Veterans Affairs, Eric Shinseki; the undersecretary for the Veterans Health Administration, Robert Petzel; and the undersecretary for the Veterans Benefits Administration, Allison Hickey. Locally, in the light of the VA wait scandal there were the firing of ...

  1. Honor on Death Row

    Directory of Open Access Journals (Sweden)

    Judy Eaton

    2014-04-01

    Full Text Available The Southern United States is described as having a culture of honor, an argument that has been used to explain higher crime rates in the Southern United States than in the rest of the country. This research explored whether the combination of honor-related violence and traditional southern politeness norms is related to regional differences in the degree of remorse expressed by those who have committed violent crimes. It was proposed that different social norms regarding politeness and apologies in the Southern United States would be reflected in the narratives provided by offenders. The data came from the final statements that offenders on death row made before they were executed. Results showed that, compared with offenders executed in the non-Southern United States, offenders executed in the South more often apologized for their crimes in their final statements, but they were not necessarily more remorseful.

  2. Bio-synthesis of gold nanoparticles by human epithelial cells, in vivo

    International Nuclear Information System (INIS)

    Larios-Rodriguez, E; Rangel-Ayon, C; Herrera-Urbina, R; Castillo, S J; Zavala, G

    2011-01-01

    Healthy epithelial cells, in vivo, have the ability to synthesize gold nanoparticles when aqueous tetrachloroauric acid is made to react with human skin. Neither a reducing agent nor a protecting chemical is needed for this bio-synthesis method. The first indication of gold nanoparticle formation is the staining of the skin, which turns deep purple. Stereoscopic optical micrographs of human skin tissue in contact with aqueous tetrachloroauric acid clearly show the staining of the epithelial cells. The UV-Vis spectrum of these epithelial cells shows an absorption band with a maximum at 553 nm. This absorption peak is within the wavelength region where the surface plasmon resonance (SPR) band of aqueous colloidal gold exhibits a maximum. Transmission electron micrographs show that gold nanoparticles synthesized by epithelial cells have sizes between 1 and 100 nm. The electron diffraction pattern of these nanoparticles reveals a crystalline structure whose interplanar distances correspond to fcc metallic gold. Transmission electron micrographs of ultra-thin (70 nm thick) slices of epithelial cells clearly and undoubtedly demonstrate that gold nanoparticles are inside the cell. According to high resolution transmission electron micrographs of intracellular single gold nanoparticles, they have the shape of a polyhedron.

  3. Gold Nanoparticles: An Efficient Antimicrobial Agent against Enteric Bacterial Human Pathogen

    Directory of Open Access Journals (Sweden)

    Shahzadi Shamaila

    2016-04-01

    Full Text Available Enteric bacterial human pathogens, i.e., Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Klebsiella pneumoniae, are the major cause of diarrheal infections in children and adults. Their structure badly affects the human immune system. It is important to explore new antibacterial agents instead of antibiotics for treatment. This project is an attempt to explain how gold nanoparticles affect these bacteria. We investigated the important role of the mean particle size, and the inhibition of a bacterium is dose-dependent. Ultra Violet (UV-visible spectroscopy revealed the size of chemically synthesized gold nanoparticle as 6–40 nm. Atomic force microscopy (AFM analysis confirmed the size and X-ray diffractometry (XRD analysis determined the polycrystalline nature of gold nanoparticles. The present findings explained how gold nanoparticles lyse Gram-negative and Gram-positive bacteria.

  4. Effect of gold nanoparticles on adipogenic differentiation of human mesenchymal stem cells

    Science.gov (United States)

    Kohl, Yvonne; Gorjup, Erwin; Katsen-Globa, Alisa; Büchel, Claudia; von Briesen, Hagen; Thielecke, Hagen

    2011-12-01

    Gold nanoparticles are very attractive for biomedical products. However, there is a serious lack of information concerning the biological activity of nanosized gold in human tissue cells. An influence of nanoparticles on stem cells might lead to unforeseen consequences to organ and tissue functions as long as all cells arising from the initial stem cell might be subsequently damaged. Therefore the effect of negatively charged gold nanoparticles (9 and 95 nm), which are certified as reference material for preclinical biomedical research, on the adipogenic differentiation of human mesenchymal stem cells (hMSCs) is investigated here. Bone marrow hMSCs are chosen as differentiation model since bone marrow hMSCs are well characterized and their differentiation into the adipogenic lineage shows clear and easily detectable differentiation. In this study effects of gold nanoparticles on adipogenic differentiation are analyzed regarding fat storage and mitochondrial activity after different exposure times (4-21 days). Using time lapse microscopy the differentiation progress under chronically gold nanoparticle treatment is continuously investigated. In this preliminary study, chronically treatment of adipogenic differentiating hMSCs with gold nanoparticles resulted in a reduced number and size of lipid vacuoles and reduced mitochondrial activity depending on the applied concentration and the surface charge of the particles.

  5. Effect of gold nanoparticles on adipogenic differentiation of human mesenchymal stem cells

    International Nuclear Information System (INIS)

    Kohl, Yvonne; Gorjup, Erwin; Katsen-Globa, Alisa; Büchel, Claudia; Briesen, Hagen von; Thielecke, Hagen

    2011-01-01

    Gold nanoparticles are very attractive for biomedical products. However, there is a serious lack of information concerning the biological activity of nanosized gold in human tissue cells. An influence of nanoparticles on stem cells might lead to unforeseen consequences to organ and tissue functions as long as all cells arising from the initial stem cell might be subsequently damaged. Therefore the effect of negatively charged gold nanoparticles (9 and 95 nm), which are certified as reference material for preclinical biomedical research, on the adipogenic differentiation of human mesenchymal stem cells (hMSCs) is investigated here. Bone marrow hMSCs are chosen as differentiation model since bone marrow hMSCs are well characterized and their differentiation into the adipogenic lineage shows clear and easily detectable differentiation. In this study effects of gold nanoparticles on adipogenic differentiation are analyzed regarding fat storage and mitochondrial activity after different exposure times (4–21 days). Using time lapse microscopy the differentiation progress under chronically gold nanoparticle treatment is continuously investigated. In this preliminary study, chronically treatment of adipogenic differentiating hMSCs with gold nanoparticles resulted in a reduced number and size of lipid vacuoles and reduced mitochondrial activity depending on the applied concentration and the surface charge of the particles.

  6. Honor, Anger, and Belittlement in Aristotle’s Ethics

    Directory of Open Access Journals (Sweden)

    Robert Sokolowski

    2014-06-01

    Full Text Available The author considers the phenomenon of honor (timē by examining Aristotle’s description of it and its role in ethical and political life. His study of honor leads him to two related phenomena, anger (orgē and belittlement or contempt (oligōria; examining them helps him define honor more precisely. With his examination of honor the author shows how densely interwoven Aristotle’s ethical theory is; he illuminates such diverse things as the human good, political life and friendship, virtue, vice, incontinence, flattery, wealth and pleasure; he shows how the metaphysical principles of dunamis and energeia are at work in human affairs; he treats the passion of anger as well as the moral attitude of contempt that provokes it, and he situates both within the study of rhetoric.

  7. Conjugation of gold nanoparticles and recombinant human endostatin modulates vascular normalization via interruption of anterior gradient 2-mediated angiogenesis.

    Science.gov (United States)

    Pan, Fan; Yang, Wende; Li, Wei; Yang, Xiao-Yan; Liu, Shuhao; Li, Xin; Zhao, Xiaoxu; Ding, Hui; Qin, Li; Pan, Yunlong

    2017-07-01

    Several studies have revealed the potential of normalizing tumor vessels in anti-angiogenic treatment. Recombinant human endostatin is an anti-angiogenic agent which has been applied in clinical tumor treatment. Our previous research indicated that gold nanoparticles could be a nanoparticle carrier for recombinant human endostatin delivery. The recombinant human endostatin-gold nanoparticle conjugates normalized vessels, which improved chemotherapy. However, the mechanism of recombinant human endostatin-gold nanoparticle-induced vascular normalization has not been explored. Anterior gradient 2 has been reported to be over-expressed in many malignant tumors and involved in tumor angiogenesis. To date, the precise efficacy of recombinant human endostatin-gold nanoparticles on anterior gradient 2-mediated angiogenesis or anterior gradient 2-related signaling cohort remained unknown. In this study, we aimed to explore whether recombinant human endostatin-gold nanoparticles could normalize vessels in metastatic colorectal cancer xenografts, and we further elucidated whether recombinant human endostatin-gold nanoparticles could interrupt anterior gradient 2-induced angiogenesis. In vivo, it was indicated that recombinant human endostatin-gold nanoparticles increased pericyte expression while inhibit vascular endothelial growth factor receptor 2 and anterior gradient 2 expression in metastatic colorectal cancer xenografts. In vitro, we uncovered that recombinant human endostatin-gold nanoparticles reduced cell migration and tube formation induced by anterior gradient 2 in human umbilical vein endothelial cells. Treatment with recombinant human endostatin-gold nanoparticles attenuated anterior gradient 2-mediated activation of MMP2, cMyc, VE-cadherin, phosphorylation of p38, and extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) in human umbilical vein endothelial cells. Our findings demonstrated recombinant human endostatin-gold nanoparticles might normalize

  8. Wear behavior of human enamel against lithium disilicate glass ceramic and type III gold.

    Science.gov (United States)

    Lee, Ahreum; Swain, Michael; He, Lihong; Lyons, Karl

    2014-12-01

    The wear behavior of human enamel that opposes different prosthetic materials is still not clear. The purpose of this in vitro study was to investigate and compare the friction and wear behavior of human tooth enamel that opposes 2 indirect restorative materials: lithium disilicate glass ceramic and Type III gold. Friction-wear tests on human enamel (n=5) that opposes lithium disilicate glass ceramic (n=5) and Type III gold (n=5) were conducted in a ball-on-flat configuration with a reciprocating wear testing apparatus. The wear pairs were subjected to a normal load of 9.8 N, a reciprocating amplitude of approximately 200 μm, and a reciprocating frequency of approximately 1.6 Hz for up to 1100 cycles per test under distilled water lubrication. The frictional force of each cycle was recorded, and the corresponding friction coefficient for different wear pairs was calculated. After wear testing, the wear scars on the enamel specimens were examined under a scanning electron microscope. Type III gold had a significantly lower steady-state friction coefficient (P=.009) and caused less wear damage on enamel than lithium disilicate glass ceramic. Enamel that opposed lithium disilicate glass ceramic exhibited cracks, plow furrows, and surface loss, which indicated abrasive wear as the prominent wear mechanism. In comparison, the enamel wear scar that opposed Type III gold had small patches of gold smear adhered to the surface, which indicated a predominantly adhesive wear mechanism. A lower friction coefficient and better wear resistance were observed when human enamel was opposed by Type III gold than by lithium disilicate glass ceramic in vitro. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  9. Partial mitigation of gold nanoparticle interactions with human lymphocytes by surface functionalization with a 'mixed matrix'.

    Science.gov (United States)

    Liptrott, Neill J; Kendall, Emily; Nieves, Daniel J; Farrell, John; Rannard, Steve; Fernig, David G; Owen, Andrew

    2014-11-01

    To investigate interactions of gold nanoparticles with primary human lymphocytes and determine if the addition of a self-assembled monolayer of 'mixed-matrix' ligands influenced these interactions. The effect of gold nanoparticles was measured by exposure to peripheral blood mononuclear cells (PBMCs) from healthy volunteers with subsequent examination of cell proliferation, cytokine secretion and CD4(+) T-cell activation relative to controls. Capped and as-synthesized gold nanoparticles augmented PBMC proliferation in response to phytohemagglutinin and this effect was greater for as-synthesized than for capped gold nanoparticles. Release of IL-10 and IFN-γ from PBMCs was increased and the effect was again more marked for as-synthesized than capped gold nanoparticles. This method provides an ex vivo approach for studying the interaction of nanoparticles with the human immune system. Further research is required to determine the specific mechanisms for reduction of immune activation seen here which could then be used to design a truly 'stealth' nanoparticle.

  10. Gold nanoparticle-assisted primer walking for closing the human chromosomal gap

    DEFF Research Database (Denmark)

    Li, H; Shi, B; Li, X

    2013-01-01

    The finished sequence of the human genome still contains 260 euchromatic gaps. All the PCR-based genome walking techniques used to close gaps have common limitations, such as low efficiency and low specificity. We herein describe a strategy to solve this problem by employing gold nanoparticles (Au...

  11. Bactericidal Effect of Gold-Chitosan Nanocomposites in Coculture Models of Pathogenic Bacteria and Human Macrophages.

    Science.gov (United States)

    Mendoza, Gracia; Regiel-Futyra, Anna; Andreu, Vanesa; Sebastián, Víctor; Kyzioł, Agnieszka; Stochel, Grażyna; Arruebo, Manuel

    2017-05-31

    The ability of pathogenic bacteria to develop resistance mechanisms to avoid the antimicrobial potential of antibiotics has become an increasing problem for the healthcare system. The search for more effective and selective antimicrobial materials, though not harmful to mammalian cells, seems imperative. Herein we propose the use of gold-chitosan nanocomposites as effective bactericidal materials avoiding damage to human cells. Nanocomposites were obtained by taking advantage of the reductive and stabilizing action of chitosan solutions on two different gold precursor concentrations. The resulting nanocomposites were added at different final concentrations to a coculture model formed by Gram-positive (Staphylococcus aureus) or Gram-negative (Escherichia coli) bacteria and human macrophages. Gold-chitosan colloids exhibited superior bactericidal ability against both bacterial models without showing cytotoxicity on human cells at the concentrations tested. Morphological and in vitro viability studies supported the feasibility of the infection model here described to test novel bactericidal nanomaterials. Flow cytometry and scanning electron microscopy analyses pointed to the disruption of the bacterial wall as the lethal mechanism. Data obtained in the present study suggest that gold-chitosan nanocomposites are powerful and promising nanomaterials for reducing bacteria-associated infections, respecting the integrity of mammalian cells, and displaying high selectivity against the studied bacteria.

  12. Human exposure to mercury due to small scale gold mining in northern Tanzania.

    Science.gov (United States)

    van Straaten, P

    2000-10-02

    In northern Tanzania large numbers of small scale miners use mercury in the gold extraction process causing contamination of the environment and risks to human health. Human exposure to Hg was assessed in populations in and around small scale gold mining camps by means of human hair and urine surveys. We also determined Hg concentration in fish in aquatic bodies close to these camps. Urinary Hg testing in three communities showed that 36% of the gold miners working with amalgam exceeded the WHO guideline concentration of 50 microg Hg/g creatinine. Data from a hair survey of fishermen and farmers confirm that at present, the fish-eating population close to the southern tip of Lake Victoria is at low risk with regard to Hg exposure. Concentrations in fish were low and > 90% of the hair samples from the fish-eating population were below 2 microg/g T-Hg. Highest Hg concentrations in fish caught along the southern shores of Lake Victoria and in rivers draining from gold processing sites were detected in lungfish species (Protopterus aethiopicus), and lowest Hg concentrations in tilapia (Oreochromis niloticus and Tilapia zilii).

  13. Biological Atomic Force Microscopy for Imaging Gold-Labeled Liposomes on Human Coronary Artery Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Ana-María Zaske

    2013-01-01

    Full Text Available Although atomic force microscopy (AFM has been used extensively to characterize cell membrane structure and cellular processes such as endocytosis and exocytosis, the corrugated surface of the cell membrane hinders the visualization of extracellular entities, such as liposomes, that may interact with the cell. To overcome this barrier, we used 90 nm nanogold particles to label FITC liposomes and monitor their endocytosis on human coronary artery endothelial cells (HCAECs in vitro. We were able to study the internalization process of gold-coupled liposomes on endothelial cells, by using AFM. We found that the gold-liposomes attached to the HCAEC cell membrane during the first 15–30 min of incubation, liposome cell internalization occurred from 30 to 60 min, and most of the gold-labeled liposomes had invaginated after 2 hr of incubation. Liposomal uptake took place most commonly at the periphery of the nuclear zone. Dynasore monohydrate, an inhibitor of endocytosis, obstructed the internalization of the gold-liposomes. This study showed the versatility of the AFM technique, combined with fluorescent microscopy, for investigating liposome uptake by endothelial cells. The 90 nm colloidal gold nanoparticles proved to be a noninvasive contrast agent that efficiently improves AFM imaging during the investigation of biological nanoprocesses.

  14. Plasmonic gold nanoparticles for detection of fungi and human cutaneous fungal infections.

    Science.gov (United States)

    Sojinrin, Tobiloba; Conde, João; Liu, Kangze; Curtin, James; Byrne, Hugh J; Cui, Daxiang; Tian, Furong

    2017-07-01

    Fungi, which are common in the environment, can cause a multitude of diseases. Warm, humid conditions allow fungi to grow and infect humans via the respiratory, digestive and reproductive tracts, genital area and other bodily interfaces. Fungi can be detected directly by microscopy, using the potassium hydroxide test, which is the gold standard and most popular method for fungal screening. However, this test requires trained personnel operating specialist equipment, including a fluorescent microscope and culture facilities. As most acutely infected patients seek medical attention within the first few days of symptoms, the optimal diagnostic test would be rapid and self-diagnostic simplifying and improving the therapeutic outcome. In suspensions of gold nanoparticles, Aspergillus niger can cause a colour change from red to blue within 2 min, as a result of changes in nanoparticle shape. A similar colour change was observed in the supernatant of samples of human toenails dispersed in water. Scanning electron microscopy, UV/Vis and Raman spectroscopy were employed to monitor the changes in morphology and surface plasmon resonance of the nanoparticles. The correlation of colour change with the fungal infection was analysed using the absorbance ratio at 520 nm/620 nm. We found a decrease in the ratio when the fungi concentration increased from 1 to 16 CFU/mL, with a detection limit of 10 CFU/mL. The test had an 80% sensitivity and a 95% specificity value for the diagnosis of athlete's foot in human patients. This plasmonic gold nanoparticle-based system for detection of fungal infections measures the change in shape of gold nanoparticles and generates coloured solutions with distinct tonality. Our application has the potential to contribute to self-diagnosis and hygiene control in laboratories/hospitals with fewer resources, just using the naked eye. Graphical abstract Colorimetric method for fungi detection with gold nano particles.

  15. Ecological and human health risks associated with abandoned gold mine tailings contaminated soil

    DEFF Research Database (Denmark)

    Ngole-Jeme, Veronica Mpode; Fantke, Peter

    2017-01-01

    Gold mining is a major source of metal and metalloid emissions into the environment. Studies were carried out in Krugersdorp, South Africa, to evaluate the ecological and human health risks associated with exposure to metals and metalloids in mine tailings contaminated soils. Concentrations......×10−2 for As and Ni respectively among children, and 5×10−3 and 4×10−3 for As and Ni respectively among adults. There is significant potential ecological and human health risk associated with metal and metalloid exposure from contaminated soils around gold mine tailings dumps. This could be a potential contributing...... of arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), lead (Pb), manganese (Mn), nickel (Ni), and zinc (Zn) in soil samples from the area varied with the highest contamination factors (expressed as ratio of metal or metalloid concentration in the tailings contaminated soil...

  16. Setup for investigating gold nanoparticle penetration through reconstructed skin and comparison to published human skin data.

    OpenAIRE

    Labouta, Hagar I; Thude, Sibylle; Schneider, Marc

    2013-01-01

    Owing to the limited source of human skin (HS) and the ethical restrictions of using animals in experiments, in vitro skin equivalents are a possible alternative for conducting particle penetration experiments. The conditions for conducting penetration experiments with model particles, 15-nm gold nanoparticles (AuNP), through nonsealed skin equivalents are described for the first time. These conditions include experimental setup, sterility conditions, effective applied dose determination, ski...

  17. Visualisation of lectin binding sites on the surface of human platelets using lectins adsorbed to gold granules.

    Science.gov (United States)

    Nurden, A T; Horisberger, M; Savariau, E; Caen, J P

    1980-10-15

    Washed human platelets have been incubated with the lectins WGA, ConA and RCA1, adsorbed to different-sized gold particles. Plasma membrane receptors for each lectin were then located by scanning and transmission electron microscopy.

  18. Inking and Thinking: Honors Students and Tattoos

    Science.gov (United States)

    Dundes, Lauren; Francis, Antonia

    2016-01-01

    This study examines whether academically accelerated students in a college Honors program are as likely as other students to acquire a tattoo and to spend the same amount of time contemplating this decision. A convenience sample of 71 honors students and 135 non-honors students completed a survey at a small mid-Atlantic liberal arts college in…

  19. Eagle Feathers, the Highest Honor.

    Science.gov (United States)

    Beaverhead, Pete

    Following his own advice that elders of the tribe share their knowledge so that "the way of the Indians would come back to the children of today," Pete Beaverhead (1899-1975) tells of the traditions of respect and honor surrounding the eagle feather in a booklet illustrated with black and white drawings. The eagle is an Indian symbol of…

  20. ACUERDO DE HONORES

    Directory of Open Access Journals (Sweden)

    Academia Colombiana de la Lengua

    2016-12-01

    destacado médico y biólogo de gran reputación internacional don Hernando Groot Liévano fue nombrado miembro del Comité Mundial de expertos en enfermedades virales.

    Que don Hernando Groot Liévano fue elegido miembro correspondiente, numerario y finalmente honorario de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales. Ocupó el cargo de vicepresidente en varios periodos.

    Que a don Hernando Groot Liévano se le reconoce como una autoridad en ética biomédica participó al lado de otros estudiosos de la Academia Nacional de Medicina y de la Federación Médica Colombiana en las mesas de trabajo que gestionaron la aprobación de la Ley 23 de 1981 sobre ética médica.

    Que don Hernando Groot Liévano fue nombrado delegado de la Academia de Medicina a la Comisión de Vocabulario Técnico de la Academia Colombiana de la Lengua. Casa que lo eligió miembro correspondiente en el año 2006 y finalmente lo exaltó a miembro honorario.

    ACUERDA

    ARTÍCULO PRIMERO. Deplorar el deceso de don Hernando Groot Liévano, cuya muerte constituye una pérdida irreparable para la Academia y para la nación.

    ARTICULO SEGUNDO. Presentar la vida y obra del académico don Hernando Groot Liévano como ejemplo sobresaliente para todos los colombianos.

    ARTICULO TERCERO. Rendir homenaje a su memoria mediante la realización de una sesión solemne en la cual se recordarán aspectos de su vida y de su obra.

    ARTÍCULO CUARTO. Copia del presente Acuerdo de Honores se enviará a sus familiares, en nota de estilo.

    Bogotá, D. C. 13 de octubre de 2016.

    JAIME POSADA Director

  1. Synthesis of curcumin-functionalized gold nanoparticles and cytotoxicity studies in human prostate cancer cell line

    Science.gov (United States)

    Nambiar, Shruti; Osei, Ernest; Fleck, Andre; Darko, Johnson; Mutsaers, Anthony J.; Wettig, Shawn

    2018-03-01

    Gold nanoparticles synthesized using plant extracts with medicinal properties have gained traction in recent years, especially for their use in various biomedical applications. Colloidal stability of these nanoparticles in different environments is critical to retain the expected therapeutic/diagnostic efficacy and toxicological outcome. Any change in the colloidal stability leads to dramatic changes in the physico-chemical properties of the nanoparticles such as size and surface charge, which in turn may alter the biological activity of the particles. Such changes are imminent in physiologically-relevant environment wherein interactions with different biomolecules, such as serum proteins, may modify the overall properties of the nanoparticles. In this regard, we synthesized 15 nm sized gold nanoparticles using curcumin, a plant extract from turmeric root, to evaluate cytotoxicity, uptake, and localization in human prostate cancer cells using cell-culture medium supplemented with or without fetal bovine serum (FBS). The results indicate a dramatic difference in the cytotoxicity and uptake between cells treated with curcumin-functionalized gold nanoparticles (cur-AuNPs) in cell-culture medium with and without serum. The addition of FBS to the medium not only increased the stability of the nanoparticles but also enhanced the biocompatibility (i.e. minimal cytotoxicity for a wide range of cur-AuNP concentrations). We conclude that the presence of serum proteins significantly impact the therapeutic potential of cur-AuNPs.

  2. Charleston/Stonewall Jackson High Schools' Honors English Program.

    Science.gov (United States)

    Kanawha County Schools, Charleston, WV.

    In the 1984-85 school year, the 3-year Honors English course was initiated at Stonewall Jackson and Charleston High Schools in Kanawha County, West Virginia. Focusing on its humanities approach to language arts instruction, this curriculum guide outlines a sequential, thematic program designed to provide students with an historical background of…

  3. Validation method for determination of cholesterol in human urine with electrochemical sensors using gold electrodes

    Science.gov (United States)

    Riyanto, Laksono, Tomy Agung

    2017-12-01

    Electrochemical sensors for the determination of cholesterol with Au as a working electrode (Au) and its application to the analysis of urine have been done. The gold electrode was prepared using gold pure (99.99%), with size 1.0 mm by length and wide respectively, connected with silver wire using silver conductive paint. Validation methods have been investigated in the analysis of cholesterol in human urine using electrochemical sensors or cyclic voltammetry (CV) method. The effect of electrolyte and uric acid concentration has been determined to produce the optimum method. Validation method parameters for cholesterol analysis in human urine using CV are precision, recovery, linearity, limit of detection (LOD) and limit of quantification (LOQ). The result showed the correlation of concentration of cholesterol to anodic peak current is the coefficient determination of R2 = 0.916. The results of the validation method showed the precision, recovery, linearity, LOD, and LOQ are 1.2539%, 144.33%, 0.916, 1.49 × 10-1 mM and 4.96 × 10-1 mM, respectively. As a conclusion is Au electrode is a good electrode for electrochemical sensors to determination of cholesterol in human urine.

  4. The Human Stratum Corneum Prevents Small Gold Nanoparticle Penetration and Their Potential Toxic Metabolic Consequences

    Directory of Open Access Journals (Sweden)

    David C. Liu

    2012-01-01

    Full Text Available Nanoparticles are being used in multiple applications, ranging from biomedical and skin care products (e.g., sunscreen through to industrial manufacturing processes (e.g., water purification. The increase in exposure has led to multiple reports on nanoparticle penetration and toxicity. However, the correlation between nanoparticle size and its penetration without physical/chemical enhancers through the skin is poorly understood—with studies instead focusing primarily on skin penetration under disrupted conditions. In this paper, we investigate the penetration and metabolic effects of 10 nm, 30 nm, and 60 nm gold nanoparticles within viable excised human skin after 24-hour exposure using multiphoton tomograph-fluorescence lifetime imaging microscopy. After 24 hour treatment with the 10, 30, and 60 nm gold nanoparticles, there was no significant penetration detected below the stratum corneum. Furthermore, there were no changes in metabolic output (total NAD(PH in the viable epidermis posttreatment correlating with lack of penetration of nanoparticles. These results are significant for estimating topical nanoparticle exposure in humans where other model systems may overestimate the exposure of nanoparticles to the viable epidermis. Our data shows that viable human skin resists permeation of small nanoparticles in a size range that has been reported to penetrate deeply in other skin models.

  5. Glucose-Coated Gold Nanoparticles Transfer across Human Brain Endothelium and Enter Astrocytes In Vitro

    Science.gov (United States)

    Gromnicova, Radka; Davies, Heather A.; Sreekanthreddy, Peddagangannagari; Romero, Ignacio A.; Lund, Torben; Roitt, Ivan M.; Phillips, James B.; Male, David K.

    2013-01-01

    The blood-brain barrier prevents the entry of many therapeutic agents into the brain. Various nanocarriers have been developed to help agents to cross this barrier, but they all have limitations, with regard to tissue-selectivity and their ability to cross the endothelium. This study investigated the potential for 4 nm coated gold nanoparticles to act as selective carriers across human brain endothelium and subsequently to enter astrocytes. The transfer rate of glucose-coated gold nanoparticles across primary human brain endothelium was at least three times faster than across non-brain endothelia. Movement of these nanoparticles occurred across the apical and basal plasma membranes via the cytosol with relatively little vesicular or paracellular migration; antibiotics that interfere with vesicular transport did not block migration. The transfer rate was also dependent on the surface coating of the nanoparticle and incubation temperature. Using a novel 3-dimensional co-culture system, which includes primary human astrocytes and a brain endothelial cell line hCMEC/D3, we demonstrated that the glucose-coated nanoparticles traverse the endothelium, move through the extracellular matrix and localize in astrocytes. The movement of the nanoparticles through the matrix was >10 µm/hour and they appeared in the nuclei of the astrocytes in considerable numbers. These nanoparticles have the correct properties for efficient and selective carriers of therapeutic agents across the blood-brain barrier. PMID:24339894

  6. Glucose-coated gold nanoparticles transfer across human brain endothelium and enter astrocytes in vitro.

    Directory of Open Access Journals (Sweden)

    Radka Gromnicova

    Full Text Available The blood-brain barrier prevents the entry of many therapeutic agents into the brain. Various nanocarriers have been developed to help agents to cross this barrier, but they all have limitations, with regard to tissue-selectivity and their ability to cross the endothelium. This study investigated the potential for 4 nm coated gold nanoparticles to act as selective carriers across human brain endothelium and subsequently to enter astrocytes. The transfer rate of glucose-coated gold nanoparticles across primary human brain endothelium was at least three times faster than across non-brain endothelia. Movement of these nanoparticles occurred across the apical and basal plasma membranes via the cytosol with relatively little vesicular or paracellular migration; antibiotics that interfere with vesicular transport did not block migration. The transfer rate was also dependent on the surface coating of the nanoparticle and incubation temperature. Using a novel 3-dimensional co-culture system, which includes primary human astrocytes and a brain endothelial cell line hCMEC/D3, we demonstrated that the glucose-coated nanoparticles traverse the endothelium, move through the extracellular matrix and localize in astrocytes. The movement of the nanoparticles through the matrix was >10 µm/hour and they appeared in the nuclei of the astrocytes in considerable numbers. These nanoparticles have the correct properties for efficient and selective carriers of therapeutic agents across the blood-brain barrier.

  7. Setup for investigating gold nanoparticle penetration through reconstructed skin and comparison to published human skin data

    Science.gov (United States)

    Labouta, Hagar I.; Thude, Sibylle; Schneider, Marc

    2013-06-01

    Owing to the limited source of human skin (HS) and the ethical restrictions of using animals in experiments, in vitro skin equivalents are a possible alternative for conducting particle penetration experiments. The conditions for conducting penetration experiments with model particles, 15-nm gold nanoparticles (AuNP), through nonsealed skin equivalents are described for the first time. These conditions include experimental setup, sterility conditions, effective applied dose determination, skin sectioning, and skin integrity check. Penetration at different exposure times (two and 24 h) and after tissue fixation (fixed versus unfixed skin) are examined to establish a benchmark in comparison to HS in an attempt to get similar results to HS experiments presented earlier. Multiphoton microscopy is used to detect gold luminescence in skin sections. λex=800 nm is used for excitation of AuNP and skin samples, allowing us to determine a relative index for particle penetration. Despite the observed overpredictability of penetration into skin equivalents, they could serve as a first fast screen for testing the behavior of nanoparticles and extrapolate their penetration behavior into HS. Further investigations are required to test a wide range of particles of different physicochemical properties to validate the skin equivalent-human skin particle penetration relationship.

  8. Gold nanoparticles enhance the X-ray-induced degradation of human centrin 2 protein

    International Nuclear Information System (INIS)

    Brun, Emilie; Duchambon, Patricia; Blouquit, Yves; Keller, Gerard; Sanche, Leon; Sicard-Roselli, Cecile

    2009-01-01

    In the war against cancer, radiotherapy is a prominent tool but counterbalanced by the fact that it also induces damages in healthy tissues. Nanotechnologies could open a new possibility to decrease these side effects. In particular, gold nanoparticles (GNPs) could be used as radio-sensitizers. As the role of proteins in the processes leading to cell death cannot be neglected, their radio-sensitization by GNPs is of great interest. This is particularly true in the case of the human centrin 2 protein, which has been proposed to be involved in DNA repair processes. To investigate this effect, we quantified for the first time the degradation of this protein in a gold colloidal solution when submitted to X-rays. We showed that the X-ray-induced degradation of the human centrin 2 protein is enhanced 1.5-fold in the presence of GNPs, even though no covalent bond exists between protein and GNPs. Among the conditions tested, the maximum enhancement was found with the higher GNP:protein ratio of 2x10 -4 and with the higher X-ray energy of 49 keV

  9. Gold nanoparticles enhance the X-ray-induced degradation of human centrin 2 protein

    Energy Technology Data Exchange (ETDEWEB)

    Brun, Emilie [Laboratoire de Chimie Physique, CNRS UMR 8000, Universite Paris-Sud 11, Bat. 350, 91405 Orsay Cedex (France); Duchambon, Patricia; Blouquit, Yves [INSERM U759, Imagerie Integrative, Campus Universitaire d' Orsay, Bat. 112, Institut Curie, Centre de Recherche, Laboratoire R. Latarjet, Campus Universitaire d' Orsay, 91405 Orsay Cedex (France); Keller, Gerard [UMR CNRS 8612, Physico-Chimie-Pharmacotechnie-Biopharmacie, Universite Paris 11, Faculte de Pharmacie, 5 rue Jean-Baptiste Clement, 92296 Chatenay-Malabry (France); Sanche, Leon [Groupe en Sciences des Radiations, Departement de Medecine Nucleaire et Radiobiologie, Faculte de Medecine, Universite de Sherbrooke, Sherbrooke, Quebec, Canada J1H 5N4 (Canada); Sicard-Roselli, Cecile [Laboratoire de Chimie Physique, CNRS UMR 8000, Universite Paris-Sud 11, Bat. 350, 91405 Orsay Cedex (France)], E-mail: cecile.sicard@u-psud.fr

    2009-03-15

    In the war against cancer, radiotherapy is a prominent tool but counterbalanced by the fact that it also induces damages in healthy tissues. Nanotechnologies could open a new possibility to decrease these side effects. In particular, gold nanoparticles (GNPs) could be used as radio-sensitizers. As the role of proteins in the processes leading to cell death cannot be neglected, their radio-sensitization by GNPs is of great interest. This is particularly true in the case of the human centrin 2 protein, which has been proposed to be involved in DNA repair processes. To investigate this effect, we quantified for the first time the degradation of this protein in a gold colloidal solution when submitted to X-rays. We showed that the X-ray-induced degradation of the human centrin 2 protein is enhanced 1.5-fold in the presence of GNPs, even though no covalent bond exists between protein and GNPs. Among the conditions tested, the maximum enhancement was found with the higher GNP:protein ratio of 2x10{sup -4} and with the higher X-ray energy of 49 keV.

  10. CTAB-coated gold nanorods elicit allergic response through degranulation and cell death in human basophils

    Science.gov (United States)

    Cheung, Ka Lun; Chen, Huanjun; Chen, Qiulan; Wang, Jianfang; Ho, Ho Pui; Wong, Chun Kwok; Kong, Siu Kai

    2012-07-01

    The effect of CTAB (cetyltrimethylammonium bromide)- or PEG (polyethylene glycol)-coated gold-nanorods (Au-NRs) on the non-IgE mediated allergic response was studied. We found that the CTAB-Au-NRs released more allergic mediators such as histamine and β-hexosaminidase from human basophil KU812, a common model for studying allergy, after 20 min incubation. Also, the CTAB-Au-NRs induced more apoptosis than the PEG-Au-NRs in KU812 24 h after treatment. These short- and long-term effects were not solely due to the CTAB residues in the supernatant desorbed from the Au-NRs.The effect of CTAB (cetyltrimethylammonium bromide)- or PEG (polyethylene glycol)-coated gold-nanorods (Au-NRs) on the non-IgE mediated allergic response was studied. We found that the CTAB-Au-NRs released more allergic mediators such as histamine and β-hexosaminidase from human basophil KU812, a common model for studying allergy, after 20 min incubation. Also, the CTAB-Au-NRs induced more apoptosis than the PEG-Au-NRs in KU812 24 h after treatment. These short- and long-term effects were not solely due to the CTAB residues in the supernatant desorbed from the Au-NRs. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr30435j

  11. Colloidal stability of gold nanorod solution upon exposure to excised human skin: Effect of surface chemistry and protein adsorption.

    Science.gov (United States)

    Mahmoud, Nouf N; Al-Qaoud, Khaled M; Al-Bakri, Amal G; Alkilany, Alaaldin M; Khalil, Enam A

    2016-06-01

    In this study, we evaluated the colloidal stability of gold nanorods (with positive, negative and neutral surface charge) in solution upon contact with excised human skin. UV-vis absorption, plasmon peak broadening index (PPBI%) and transmission electron microscope analysis were used to follow nanoparticles aggregation in solution. Our results show that positively charged gold nanorods aggregate extensively upon exposure to excised human skin compared to negatively and neutrally charged gold nanorods. Skin-induced aggregation of cationic gold nanorods was linked to the adsorption of proteins released from the dermis layer to the surface of gold nanorods. Protein adsorption significantly screen nanorod's effective surface charge and induce their aggregation. Moreover, we demonstrate that the presence of polyethylene glycol polymer on the surface of cationic gold nanorods minimize this aggregation significantly by providing steric repulsion (non-electrostatic stabilization mechanism). This work highlights the importance of evaluating the colloidal stability of nanoparticles in solution upon contact with skin, which is a "usually overlooked" parameter when studying the nanoparticle-skin interaction. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Renaissance of nuclear medicine through green nanotechnology. Functionalized radioactive gold nanoparticles in cancer therapy - my journey from chemistry to saving human lives

    International Nuclear Information System (INIS)

    Katti, K.V.

    2016-01-01

    First of all, I take great pleasure in thanking the international jury of subject experts who have selected me to receive the 2015 Hevesy Medal Award. It is a great honor for me and my institution, the University of Missouri, Columbia, USA, to join the illustrious list of former awardees of this internationally reputed Hevesy Medal Award being conferred to me today. I also take this opportunity to thank my teachers, mentors from India, Germany, Canada and the United States, who have trained and mentored me over the years. I also thank various faculty collaborators, post-doctoral fellows, graduate and undergraduate students who have contributed immensely to my research enterprise over the last 30 years - without whom achievements such as the Hevesy Medal Award - wouldn't have been a reality. I also express my heartfelt gratitude to my wife and co-worker, Kavita, who is among the audience here today, our children, my parents and my late in-laws and various relatives for all their support over the years. In this Hevesy Medal Award lecture, I will discuss brief details of a plethora of discoveries made in my laboratories in the general field of nuclear medicine especially as it relates to the creation of a scientifically sound rationale toward the development of 'nano-sized radiopharmaceuticals' through novel green nanotechnology approaches. In this lecture, I have planned to discuss Critical needs and importance of thinking 'Out of the Box' in discovering new and more effective approaches for cancer therapy; The role of radioactive gold nanoparticles in bringing about a paradigm shift toward the development of a new generation of nano Radiopharmaceuticals for applications in diagnostics and therapy; Details on the production of radioactive gold-198 nanoparticles with extensive preclinical investigations in tumor bearing mice and dogs and, finally Oncological implications as the emerging field of nano radiopharmaceuticals has the potential to

  13. The Geomorphic System and the Effects of Human Interference at Gold Coast Beach in Tainan, Taiwan

    Science.gov (United States)

    Lin, Tsung-Yi

    2017-04-01

    The Gold Coast beach in Tainan, Taiwan, located between Anping harbor and Ur-Jen river mouth, is the subject of this study, which characterizes the beach's geomorphic system through the analysis of information such as sediment grain size, mineral composition, and periodic measurements of morphological changes of the beach. Based upon such characterizations, further analysis is conducted on the effects that human activities of the last 15 years have upon the geomorphic changes within the Gold Coast beach. The study shows that the median grain size of the Gold Coast beach's sediment is medium sand. The mineral composition includes mainly slate fragments and quartz grains, with small amounts of feldspar, sandstone and shell fragments. Based on a comprehensive study of the longshore distribution of beach sediment size and mineral composition of southwestern coast of Taiwan, as well as, the long-term, monitored data of waves, tides, and currents in this region, we conclude that the main process responsible for the sand accumulation at Gold Coast beach is the prevailing longshore sand transport from south to north. The southern breakwater of Anping harbor plays a role in intercepting the longshore transport sand and helps form the beach. Since the Ur-Jen river flows through a mudstone region, the suspended sediment plume during the flood season does not provide much sediment source to the sandy beach. A monthly beach profile survey project conducted between the years 1999 to 2000 revealed that the beach elevation and width had experienced an obvious seasonal change. The beach widened during the winter, but narrowed in the summer due to typhoon wave erosion. When the subaerial beach was eroded, a submerged longshore bar that was oriented almost parallel to the shoreline had formed at a distance about 400-600 meter away. With this observation, we can conclude that beach morphology is also influenced by various seasonal wave actions that affect onshore and offshore sand

  14. An Effective Honors Composition Class Improves Honors Retention Rates: Outcomes and Statistical Prestidigitation

    Science.gov (United States)

    Guzy, Annmarie

    2014-01-01

    Annmarie Guzy teaches honors composition at the University of South Alabama. This essay discusses her observation that students who took her class were more likely to complete the honors program, which led to her wondering what elements of her course might give students an edge in honors program completion. As an English professor with training in…

  15. Honors Teachers and Academic Identity: What to Look for When Recruiting Honors Faculty

    Science.gov (United States)

    Dailey, Rocky

    2016-01-01

    To be a collegiate honors student implies a higher level of academic achievement than other students as well as the more challenging academic experience that comes with smaller class sizes. Collegiate honors teachers have a distinction of their own. Being an honors teacher implies a high level of teaching achievement, and it requires special…

  16. Honor and I: Differential relationships between honor and self-esteem in three cultural groups

    NARCIS (Netherlands)

    Novin, Sheida; Tatar, Betul; Krabbendam, Lydia

    2015-01-01

    Honor is often defined as one's self-esteem through one's own eyes as through the eyes of others. This definition assumes that endorsing honor values is universally related to one's self-esteem. Yet, prior work shows that the salience of honor in individuals' lives differs across cultures, which

  17. The Honors Thesis: A Handbook for Honors Directors, Deans, and Faculty Advisors. National Collegiate Honors Council Monograph Series

    Science.gov (United States)

    Anderson, Mark; Lyons, Karen; Weiner, Norman

    2014-01-01

    This handbook is intended to help all those who design, administer, and implement honors thesis programs--honors directors, deans, staff, faculty, and advisors--evaluate their thesis programs, solve pressing problems, select more effective requirements or procedures, or introduce an entirely new thesis program. The authors' goal is to provide…

  18. Effects of Gold Salt Speciation and Structure of Human and Bovine Serum Albumins on the Synthesis and Stability of Gold Nanostructures.

    Science.gov (United States)

    Miranda, Érica G A; Tofanello, Aryane; Brito, Adrianne M M; Lopes, David M; Albuquerque, Lindomar J C; de Castro, Carlos E; Costa, Fanny N; Giacomelli, Fernando C; Ferreira, Fabio F; Araújo-Chaves, Juliana C; Nantes, Iseli L

    2016-01-01

    The present study aimed to investigate the influence of albumin structure and gold speciation on the synthesis of gold nanoparticles (GNPs). The strategy of synthesis was the addition of HAuCl4 solutions at different pH values (3-12) to solutions of human and bovine serum albumins (HSA and BSA) at the same corresponding pH values. Different pH values influence the GNP synthesis due to gold speciation. Besides the inherent effect of pH on the native structure of albumins, the use N-ethylmaleimide (NEM)-treated and heat-denaturated forms of HSA and BSA provided additional insights about the influence of protein structure, net charge, and thiol group approachability on the GNP synthesis. NEM treatment, heating, and the extreme values of pH promoted loss of the native albumin structure. The formation of GNPs indicated by the appearance of surface plasmon resonance (SPR) bands became detectable from 15 days of the synthesis processes that were carried out with native, NEM-treated and heat-denaturated forms of HSA and BSA, exclusively at pH 6 and 7. After 2 months of incubation, SPR band was also detected for all synthesis carried out at pH 8.0. The mean values of the hydrodynamic radius (RH) were 24 and 34 nm for GNPs synthesized with native HSA and BSA, respectively. X-ray diffraction (XRD) revealed crystallites of 13 nm. RH, XRD, and zeta potential values were consistent with GNP capping by the albumins. However, the GNPs produced with NEM-treated and heat-denaturated albumins exhibited loss of protein capping by lowering the ionic strength. This result suggests a significant contribution of non-electrostatic interactions of albumins with the GNP surface, in these conditions. The denaturation of proteins exposes hydrophobic groups to the solvent, and these groups could interact with the gold surface. In these conditions, the thiol blockage or oxidation, the latter probably favored upon heating, impaired the formation of a stable capping by thiol coordination with the

  19. Rapid Synthesis of Gold Nanoparticles from Quercus incana and Their Antimicrobial Potential against Human Pathogens

    Directory of Open Access Journals (Sweden)

    Rizwana Sarwar

    2017-01-01

    Full Text Available In current study, bioreduction of tetrachloroauric acid (HAuCl4·3H2O was carried out using leaves extract of Quercus incana for nanoparticle synthesis. The nanoparticles were characterized by ultraviolet visible spectrum (UV, Fourier-transform infrared (FT-IR, and transmission electron microscopy (TEM analysis. The gold nanoparticles (GNPs were generally clumpy agglomerates of polydispersed particles, with an average size in the range 5.5–10 nm. The Gas chromatography–mass spectrometry (GC–MS qualitative analysis and FT-IR data supported the presence of bioactive compounds, which are responsible for the metal reduction and nanoparticles stabilization. The biocompatibility of synthesized GNPs was evaluated via antibacterial activity by using human bacterial pathogens. The results showed that synthesized GNPs showed enhanced antibacterial activity against all bacterial pathogens.

  20. Assessment of human and ecological risks from uranium and gold mining activities

    International Nuclear Information System (INIS)

    Hart, D.; McKee, P.; Garisto, N.

    1995-01-01

    Forecasting of ecological and human health risk has been widely used in the uranium mining industry to support decisions regarding acceptability of proposed mine developments and mine closure plans. Probabilistic assessment has been less frequently used in other mining sectors where radiological issues are less prominent, but is now beginning to be more broadly applied. Case studies are presented to illustrate probabilistic approaches in opening and closing assessments of uranium and gold mines. Risks to man and biota from operational emissions (radionuclides, arsenic, cyanide) and risk reductions following mine closure are forecast using probabilistic models of chemical fate, transport and exposure. These forecasts permit selection of operational and closure alternatives which produce acceptably low risks

  1. Stimulating professional development and teaching strategies of honors teachers

    NARCIS (Netherlands)

    Liliane Eggens; Drs. Elles Kazemier; Inge Wijkamp

    2013-01-01

    Professional development of teachers in honors programs. Presentation, Honors Conference: Learning to innovate – Evoking professional excellence in higher education, Hogeschool van Rotterdam. Rotterdam, 5 oktober 2013 Focus: Development of honors teaching strategies Research: Professional

  2. Learning as salon : Honors international collaboration

    NARCIS (Netherlands)

    Corinne Mann; Justin van Dijk; Dr. Marca Wolfensberger; Mischa Dekker; Chantel Lucas; Christine Hait; John Zubizarreta

    2013-01-01

    In May 2011, Dutch students from the honors program in geosciences of Utrecht University, led by Professor Marca Wolfensberger, engaged in an experimental-learning project in Paris, France, with a group of American students from the honors program of Columbia College, South Carolina, led by

  3. Medal of Honor Recipients: 1979-2004

    National Research Council Canada - National Science Library

    Richardson, Glenda

    2004-01-01

    .... Although the Persian Gulf War, Operation Enduring Freedom, and Operation Iraqi Freedom are listed in the Table of Contents, as of this writing, no Medals of Honor have been awarded for actions in these conflicts. For further information, see CRS Report 95-519, "Medal of Honor: History and Issues." This report will be updated as new recipients are named.

  4. Research on Honors Composition, 2004-2015

    Science.gov (United States)

    Guzy, Annmarie

    2016-01-01

    This bibliography is intended to offer future honors composition researchers a comprehensive list of honors composition publications and disciplinary presentations to date. Guzy's intent was to provide a starting place for future researchers to begin their literature reviews and to decide which research agenda to pursue. Guzy focused on…

  5. Honoring Teachers for Their Vocation and Potential

    Science.gov (United States)

    Williams, Raymond Brady

    2007-01-01

    One goal of the Wabash Center is to honor teachers for their potential, and hospitality has been a primary means to that end. A lesson learned is that the intention and effort to honor teachers create contexts for meaningful discussions, creative learning, and personal renewal of those engaged in workshops and consultations. The lesson is valuable…

  6. Honors in Honduras: Engaged Learning in Action

    Science.gov (United States)

    Folds-Bennett, Trisha; Twomey, Mary Pat

    2013-01-01

    A significant challenge in honors education is providing experiences through which students deeply engage ideas and content so that their analytical abilities and core beliefs and values are transformed. The College of Charleston Honors College aimed to stimulate critical thinking and examination of core values through a more holistic approach to…

  7. Layer-by-layer assembly of gold nanoparticles and cysteamine on gold electrode for immunosensing of human chorionic gonadotropin at picogram levels.

    Science.gov (United States)

    Roushani, Mahmoud; Valipour, Akram; Valipour, Mehdi

    2016-04-01

    The development of an electrochemical immunosensor for the detection of human chorionic gonadotropin (hCG) is described with a limit of detection as low as 0.3 pg mL(-1) in phosphate buffer. In this immunosensor, cysteamine (Cys) and gold nanoparticles (AuNPs) were used to immobilize an anti-hCG monoclonal antibody onto a gold electrode (GE). The structure of AuNPs has been confirmed by EDS, SEM, and TEM analysis. Due to the large specific surface area and excellent electrical conductivity of AuNPs, electron transfer was promoted and the amount of hCG antibody was enhanced significantly. A systematic study on the effects of experimental parameters such as pH, incubation time in the hCG solution and urea solution used for experiments on the binding between the immobilized antibody and hCG has been carried out. Under optimal experimental parameters, differential pulse voltammetry (DPV) signal changes of the [Fe(CN)6](3-/4-) are used to detect hCG with two broad linear ranges: 0.001 to 0.2 and 0.2 to 60.7 ng mL(-1). The LOD value proves more sensitive in comparison with previously reported methods. The prepared immunosensor showed high sensitivity and stability. In addition, the immunosensor was successfully used for the determination of hCG in human serum. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. School violence and the culture of honor.

    Science.gov (United States)

    Brown, Ryan P; Osterman, Lindsey L; Barnes, Collin D

    2009-11-01

    We investigated the hypothesis that a sociocultural variable known as the culture of honor would be uniquely predictive of school-violence indicators. Controlling for demographic characteristics associated in previous studies with violent crime among adults, we found that high-school students in culture-of-honor states were significantly more likely than high-school students in non-culture-of-honor states to report having brought a weapon to school in the past month. Using data aggregated over a 20-year period, we also found that culture-of-honor states had more than twice as many school shootings per capita as non-culture-of-honor states. The data revealed important differences between school violence and general patterns of homicide and are consistent with the view that many acts of school violence reflect retaliatory aggression springing from intensely experienced social-identity threats.

  9. Label-Free Detection of Rare Cell in Human Blood Using Gold Nano Slit Surface Plasmon Resonance

    Directory of Open Access Journals (Sweden)

    Mansoureh Z. Mousavi

    2015-03-01

    Full Text Available Label-free detection of rare cells in biological samples is an important and highly demanded task for clinical applications and various fields of research, such as detection of circulating tumor cells for cancer therapy and stem cells studies. Surface Plasmon Resonance (SPR as a label-free method is a promising technology for detection of rare cells for diagnosis or research applications. Short detection depth of SPR (400 nm provides a sensitive method with minimum interference of non-targets in the biological samples. In this work, we developed a novel microfluidic chip integrated with gold nanoslit SPR platform for highly efficient immunomagnetic capturing and detection of rare cells in human blood. Our method offers simple yet efficient detection of target cells with high purity. The approach for detection consists of two steps. Target cells are firs captured on functionalized magnetic nanoparticles (MNPs with specific antibody I. The suspension containing the captured cells (MNPs-cells is then introduced into a microfluidic chip integrated with a gold nanoslit film. MNPs-cells bind with the second specific antibody immobilized on the surface of the gold nanoslit and are therefore captured on the sensor active area. The cell binding on the gold nanoslit was monitored by the wavelength shift of the SPR spectrum generated by the gold nanoslits.

  10. The Economic Returns to Graduating with Honors - Evidence from Law Graduates

    OpenAIRE

    Schumann, Mathias; Freier, Ronny; Siedler, Thomas

    2014-01-01

    This paper studies the causal effects of graduating from university with an honors degree on subsequent labor market outcomes. While a rich body of literature has focused on estimating returns to human capital, few studies have analyzed returns at the very top of the education distribution. We highlight the importance of honors degrees for future labor market success in the context of German law graduates. Using a difference-in-differences research design combined with entropy balancing, we f...

  11. AGU honored for Antarctic book

    Science.gov (United States)

    AGU has won an honorable mention award at the Fifteenth Annual Awards Program for Excellence in Professional and Scholarly Publishing sponsored by the Association of American Publishers for the book Volcanoes of the Antarctic Plate and Southern Oceans. The book is part of AGU's Antarctic Research Series, an outgrowth of research done during the International Geophysical Year that was begun in 1963 with a grant from the National Science Foundation. The award was presented at the AAP Annual Awards Dinner on February 6 at the Ritz-Carlton Hotel in Washington, D.C. The award consists of a medallion and a plate on which the names of the publisher, title, and authors are engraved.

  12. Ecological and human health risks associated with abandoned gold mine tailings contaminated soil.

    Directory of Open Access Journals (Sweden)

    Veronica Mpode Ngole-Jeme

    Full Text Available Gold mining is a major source of metal and metalloid emissions into the environment. Studies were carried out in Krugersdorp, South Africa, to evaluate the ecological and human health risks associated with exposure to metals and metalloids in mine tailings contaminated soils. Concentrations of arsenic (As, cadmium (Cd, chromium (Cr, cobalt (Co, copper (Cu, lead (Pb, manganese (Mn, nickel (Ni, and zinc (Zn in soil samples from the area varied with the highest contamination factors (expressed as ratio of metal or metalloid concentration in the tailings contaminated soil to that of the control site observed for As (3.5x102, Co (2.8x102 and Ni (1.1x102. Potential ecological risk index values for metals and metalloids determined from soil metal and metalloid concentrations and their respective risk factors were correspondingly highest for As (3.5x103 and Co (1.4x103, whereas Mn (0.6 presented the lowest ecological risk. Human health risk was assessed using Hazard Quotient (HQ, Chronic Hazard Index (CHI and carcinogenic risk levels, where values of HQ > 1, CHI > 1 and carcinogenic risk values > 1×10-4 represent elevated risks. Values for HQ indicated high exposure-related risk for As (53.7, Cr (14.8, Ni (2.2, Zn (2.64 and Mn (1.67. Children were more at risk from heavy metal and metalloid exposure than adults. Cancer-related risks associated with metal and metalloid exposure among children were also higher than in adults with cancer risk values of 3×10-2 and 4×10-2 for As and Ni respectively among children, and 5×10-3 and 4×10-3 for As and Ni respectively among adults. There is significant potential ecological and human health risk associated with metal and metalloid exposure from contaminated soils around gold mine tailings dumps. This could be a potential contributing factor to a setback in the health of residents in informal settlements dominating this mining area as the immune systems of some of these residents are already compromised by high

  13. Overendocytosis of gold nanoparticles increases autophagy and apoptosis in hypoxic human renal proximal tubular cells

    Directory of Open Access Journals (Sweden)

    Ding F

    2014-09-01

    Full Text Available Fengan Ding,1 Yiping Li,1 Jing Liu,1 Lei Liu,1 Wenmin Yu,1 Zhi Wang,1 Haifeng Ni,2 Bicheng Liu,2 Pingsheng Chen1,2 1School of Medicine, Southeast University, Nanjing, People’s Republic of China; 2Institute of Nephrology, The Affiliated Zhongda Hospital, Southeast University, Nanjing, People’s Republic of China Background: Gold nanoparticles (GNPs can potentially be used in biomedical fields ranging from therapeutics to diagnostics, and their use will result in increased human exposure. Many studies have demonstrated that GNPs can be deposited in the kidneys, particularly in renal tubular epithelial cells. Chronic hypoxic is inevitable in chronic kidney diseases, and it results in renal tubular epithelial cells that are susceptible to different types of injuries. However, the understanding of the interactions between GNPs and hypoxic renal tubular epithelial cells is still rudimentary. In the present study, we characterized the cytotoxic effects of GNPs in hypoxic renal tubular epithelial cells.Results: Both 5 nm and 13 nm GNPs were synthesized and characterized using various biophysical methods, including transmission electron microscopy, dynamic light scattering, and ultraviolet–visible spectrophotometry. We detected the cytotoxicity of 5 and 13 nm GNPs (0, 1, 25, and 50 nM to human renal proximal tubular cells (HK-2 by Cell Counting Kit-8 assay and lactate dehydrogenase release assay, but we just found the toxic effect in the 5 nm GNP-treated cells at 50 nM dose under hypoxic condition. Furthermore, the transmission electron microscopy images revealed that GNPs were either localized in vesicles or free in the lysosomes in 5 nm GNPs-treated HK-2 cells, and the cellular uptake of the GNPs in the hypoxic cells was significantly higher than that in normoxic cells. In normoxic HK-2 cells, 5 nm GNPs (50 nM treatment could cause autophagy and cell survival. However, in hypoxic conditions, the GNP exposure at the same condition led to the

  14. Highly efficient inhibition of human immunodeficiency virus type 1 reverse transcriptase by aptamers functionalized gold nanoparticles

    Science.gov (United States)

    Shiang, Yen-Chun; Ou, Chung-Mao; Chen, Shih-Ju; Ou, Ting-Yu; Lin, Han-Jia; Huang, Chih-Ching; Chang, Huan-Tsung

    2013-03-01

    We have developed aptamer (Apt)-conjugated gold nanoparticles (Apt-Au NPs, 13 nm in diameter) as highly effective inhibitors for human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT). Two Apts, RT1t49 (Aptpol) and ODN 93 (AptRH), which recognize the polymerase and RNase H regions of HIV-1 RT, are used to conjugate Au NPs to prepare Aptpol-Au NPs and AptRH-Au NPs, respectively. In addition to DNA sequence, the surface density of the aptamers on Au NPs (nApt-Au NPs; n is the number of aptamer molecules on each Au NP) and the linker length number (Tm; m is the base number of the deoxythymidine linker) between the aptamer and Au NPs play important roles in determining their inhibition activity. A HIV-lentiviral vector-based antiviral assay has been applied to determine the inhibitory effect of aptamers or Apt-Au NPs on the early stages of their replication cycle. The nuclease-stable G-quadruplex structure of 40AptRH-T45-Au NPs shows inhibitory efficiency in the retroviral replication cycle with a decreasing infectivity (40.2%).We have developed aptamer (Apt)-conjugated gold nanoparticles (Apt-Au NPs, 13 nm in diameter) as highly effective inhibitors for human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT). Two Apts, RT1t49 (Aptpol) and ODN 93 (AptRH), which recognize the polymerase and RNase H regions of HIV-1 RT, are used to conjugate Au NPs to prepare Aptpol-Au NPs and AptRH-Au NPs, respectively. In addition to DNA sequence, the surface density of the aptamers on Au NPs (nApt-Au NPs; n is the number of aptamer molecules on each Au NP) and the linker length number (Tm; m is the base number of the deoxythymidine linker) between the aptamer and Au NPs play important roles in determining their inhibition activity. A HIV-lentiviral vector-based antiviral assay has been applied to determine the inhibitory effect of aptamers or Apt-Au NPs on the early stages of their replication cycle. The nuclease-stable G-quadruplex structure of 40AptRH-T45

  15. Consider Your Man Card Reissued: Masculine Honor and Gun Violence

    Science.gov (United States)

    Shuffelton, Amy

    2015-01-01

    In this article, Amy Shuffelton addresses school shootings through an investigation of honor and masculinity. Drawing on recent scholarship on honor, including Bernard Williams's "Shame and Necessity" and Kwame Anthony Appiah's "The Honor Code," Shuffelton points out that honor has been misconstrued as exclusively a matter of…

  16. Layer-by-layer assembly of gold nanoparticles and cysteamine on gold electrode for immunosensing of human chorionic gonadotropin at picogram levels

    Energy Technology Data Exchange (ETDEWEB)

    Roushani, Mahmoud, E-mail: mahmoudroushani@yahoo.com [Department of Chemistry, Ilam University, P.O. Box, 69315-516, Ilam (Iran, Islamic Republic of); Valipour, Akram [Department of Chemistry, Ilam University, P.O. Box, 69315-516, Ilam (Iran, Islamic Republic of); Valipour, Mehdi [Department of Chemistry, Payame Noor University, P.O. Box, 19395-3697, Tehran (Iran, Islamic Republic of)

    2016-04-01

    The development of an electrochemical immunosensor for the detection of human chorionic gonadotropin (hCG) is described with a limit of detection as low as 0.3 pg mL{sup −1} in phosphate buffer. In this immunosensor, cysteamine (Cys) and gold nanoparticles (AuNPs) were used to immobilize an anti-hCG monoclonal antibody onto a gold electrode (GE). The structure of AuNPs has been confirmed by EDS, SEM, and TEM analysis. Due to the large specific surface area and excellent electrical conductivity of AuNPs, electron transfer was promoted and the amount of hCG antibody was enhanced significantly. A systematic study on the effects of experimental parameters such as pH, incubation time in the hCG solution and urea solution used for experiments on the binding between the immobilized antibody and hCG has been carried out. Under optimal experimental parameters, differential pulse voltammetry (DPV) signal changes of the [Fe(CN){sub 6}]{sup 3−/4−} are used to detect hCG with two broad linear ranges: 0.001 to 0.2 and 0.2 to 60.7 ng mL{sup −1}. The LOD value proves more sensitive in comparison with previously reported methods. The prepared immunosensor showed high sensitivity and stability. In addition, the immunosensor was successfully used for the determination of hCG in human serum. - Highlights: • AuNPs were used for covalent attachment of anti-body onto GE. • AuNPs joint to GE via Cys, which were similar to electron-transfer tunnel. • A simple method and a sensitive immunosensing for hCG were reported.

  17. Layer-by-layer assembly of gold nanoparticles and cysteamine on gold electrode for immunosensing of human chorionic gonadotropin at picogram levels

    International Nuclear Information System (INIS)

    Roushani, Mahmoud; Valipour, Akram; Valipour, Mehdi

    2016-01-01

    The development of an electrochemical immunosensor for the detection of human chorionic gonadotropin (hCG) is described with a limit of detection as low as 0.3 pg mL −1 in phosphate buffer. In this immunosensor, cysteamine (Cys) and gold nanoparticles (AuNPs) were used to immobilize an anti-hCG monoclonal antibody onto a gold electrode (GE). The structure of AuNPs has been confirmed by EDS, SEM, and TEM analysis. Due to the large specific surface area and excellent electrical conductivity of AuNPs, electron transfer was promoted and the amount of hCG antibody was enhanced significantly. A systematic study on the effects of experimental parameters such as pH, incubation time in the hCG solution and urea solution used for experiments on the binding between the immobilized antibody and hCG has been carried out. Under optimal experimental parameters, differential pulse voltammetry (DPV) signal changes of the [Fe(CN) 6 ] 3−/4− are used to detect hCG with two broad linear ranges: 0.001 to 0.2 and 0.2 to 60.7 ng mL −1 . The LOD value proves more sensitive in comparison with previously reported methods. The prepared immunosensor showed high sensitivity and stability. In addition, the immunosensor was successfully used for the determination of hCG in human serum. - Highlights: • AuNPs were used for covalent attachment of anti-body onto GE. • AuNPs joint to GE via Cys, which were similar to electron-transfer tunnel. • A simple method and a sensitive immunosensing for hCG were reported.

  18. Gold nanoparticles in injectable calcium phosphate cement enhance osteogenic differentiation of human dental pulp stem cells.

    Science.gov (United States)

    Xia, Yang; Chen, Huimin; Zhang, Feimin; Bao, Chongyun; Weir, Michael D; Reynolds, Mark A; Ma, Junqing; Gu, Ning; Xu, Hockin H K

    2018-01-01

    In this study, a novel calcium phosphate cement containing gold nanoparticles (GNP-CPC) was developed. Its osteogenic induction ability on human dental pulp stem cells (hDPSCs) was investigated for the first time. The incorporation of GNPs improved hDPSCs behavior on CPC, including better cell adhesion (about 2-fold increase in cell spreading) and proliferation, and enhanced osteogenic differentiation (about 2-3-fold increase at 14 days). GNPs endow CPC with micro-nano-structure, thus improving surface properties for cell adhesion and subsequent behaviors. In addition, GNPs released from GNP-CPC were internalized by hDPSCs, as verified by transmission electron microscopy (TEM), thus enhancing cell functions. The culture media containing GNPs enhanced the cellular activities of hDPSCs. This result was consistent with and supported the osteogenic induction results of GNP-CPC. In conclusion, GNP-CPC significantly enhanced the osteogenic functions of hDPSCs. GNPs are promising to modify CPC with nanotopography and work as bioactive additives thus enhance bone regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Endowed Professorship In Veterinary College Honors Young

    OpenAIRE

    Douglas, Jeffrey S.

    2003-01-01

    One of the Virginia-Maryland Regional College of Veterinary Medicine's leading infectious diseases specialists has been named to a recently created endowed professorship that honors a veterinarian who studied at Virginia Tech almost 60 years ago.

  20. DNA-Gadolinium-Gold nanoparticles for in vivo T1 MR imaging of transplanted human neural stem cells

    OpenAIRE

    Nicholls, Francesca J.; Rotz, Matthew W.; Ghuman, Harman; MacRenaris, Keith W.; Meade, Thomas J.; Modo, Michel

    2015-01-01

    The unambiguous imaging of transplanted cells remains a major challenge to understand their biological function and therapeutic efficacy. In vivo imaging of implanted cells is reliant on tagging these to differentiate them from host tissue, such as the brain. We here characterize a gold nanoparticle conjugate that is functionalized with modified deoxythymidine oligonucleotides bearing Gd(III) chelates and a red fluorescent Cy3 moiety to visualize in vivo transplanted human neural stem cells. ...

  1. Human health risk assessment of mercury vapor around artisanal small-scale gold mining area, Palu city, Central Sulawesi, Indonesia.

    Science.gov (United States)

    Nakazawa, Koyomi; Nagafuchi, Osamu; Kawakami, Tomonori; Inoue, Takanobu; Yokota, Kuriko; Serikawa, Yuka; Cyio, Basir; Elvince, Rosana

    2016-02-01

    Emissions of elemental mercury, Hg(0), from artisanal small-scale gold mining activities accounted for 37% of total global Hg(0) emissions in 2010. People who live near gold-mining areas may be exposed to high concentrations of Hg(0). Here, we assessed the human health risk due to Hg(0) exposure among residents of Palu city (Central Sulawesi Province, Indonesia). The area around the city has more than 60t of gold reserves, and the nearby Poboya area is the most active gold-mining site in Indonesia. Owing to its geography, the city experiences alternating land and sea breezes. Sampling was done over a period of 3 years (from 2010 Aug. to 2012 Dec.) intermittently with a passive sampler for Hg(0), a portable handheld mercury analyzer, and a mercury analyzer in four areas of the city and in the Poboya gold-processing area, as well as wind speeds and directions in one area of the city. The 24-h average concentration, wind speed, and wind direction data show that the ambient air in both the gold-processing area and the city was always covered by high concentration of mercury vapor. The Hg(0) concentration in the city was higher at night than in the daytime, owing to the effect of land breezes. These results indicate that the inhabitants of the city were always exposed to high concentrations of Hg(0). The average daytime point-sample Hg(0) concentrations in the city, as measured with a handheld mercury analyzer over 3 days in July 2011, ranged from 2096 to 3299ngm(-3). In comparison, the average daytime Hg(0) concentration in the Poboya gold-processing area was 12,782ngm(-3). All of these concentrations are substantially higher than the World Health Organization air-quality guideline for annual average Hg exposure (1000ngm(-3)). We used the point-sample concentrations to calculate hazard quotient ratios by means of a probabilistic risk assessment method. The results indicated that 93% of the sample population overall was at risk (hazard quotient ratio ≥1 and cut off at

  2. Honoring Controversy: Using Real-World Problems to Teach Critical Thinking in Honors Courses

    Science.gov (United States)

    Cargas, Sarita

    2016-01-01

    In this article Sarita Cargas suggests that getting honors students used to analyzing controversies will contribute to their developing a disposition toward critical thinking. She goes on to say that the value of teaching critical-thinking skills complements the movement of many honors programs toward teaching more than just disciplinary content.…

  3. Academic success and early career outcomes : Can honors alumni be distinguished from non-honors alumni?

    NARCIS (Netherlands)

    Kool, A.; Mainhard, M. T.; Brekelmans, M.; van Beukelen, P.; Jaarsma, Alexandra

    2016-01-01

    This study compared Dutch alumni who previously participated in an honors program (n=72) to non-honors alumni who entered university as high-achieving high school students (n=72) with regard to (1) final university grade point average (GPA) and (2) early career outcomes. Final grades were drawn from

  4. Academic success and early career outcomes : Can honors alumni be distinguished from non-honors alumni?

    NARCIS (Netherlands)

    Kool, A.; Mainhard, M. T.; Jaarsma, A. D C; Brekelmans, M.; van Beukelen, P.

    2016-01-01

    This study compared Dutch alumni who previously participated in an honors program (n = 72) to non-honors alumni who entered university as high-achieving high school students (n = 72) with regard to (1) final university grade point average (GPA) and (2) early career outcomes. Final grades were drawn

  5. [Human mercury exposure and irregular menstrual cycles in relation to artisanal gold mining in Colombia].

    Science.gov (United States)

    Rodríguez-Villamizar, Laura Andrea; Jaimes, Diana Carolina; Manquián-Tejos, Adelaida; Sánchez, Luz Helena

    2015-08-01

    Artisanal mining commonly extracts gold with an amalgamation process that uses mercury. The reproductive effects from exposure to elemental mercury used in gold mining have not been sufficiently studied. To evaluate the effect of the exposure to elemental mercury used in gold mining on menstrual cycle regularity and the occurrence of miscarriages in Colombia. An analytical cross-sectional study was conducted. The participants were female residents of gold mining districts, with a history of exposure to elemental mercury. Menstrual regularity and the occurrence of miscarriages were compared between these women and an unexposed group. Exposure and outcome variables were registered based on a questionnaire which was evaluated for its test-retest reproducibility. Prevalence rates were calculated using a binomial model and goodness-of-fit was evaluated. A total of 72 women exposed to mercury and 121 unexposed women participated. The average time of exposure to mercury among exposed women was 19.58 ± 9.53 years. The adjusted prevalence of irregular menstruation over the last six months was higher in the group of women chronically exposed to mercury vapors (PR=1.59, 95% CI 0.93-2.73), while there was no difference in the proportion of women with a history of miscarriages. Exposure to elemental mercury used in artisanal gold mining may be associated with a higher prevalence of irregular menstrual cycles but not with the occurrence of miscarriage.

  6. Interaction of gold and silver nanoparticles with human plasma: Analysis of protein corona reveals specific binding patterns.

    Science.gov (United States)

    Lai, Wenjia; Wang, Qingsong; Li, Lumeng; Hu, Zhiyuan; Chen, Jiankui; Fang, Qiaojun

    2017-04-01

    Determining how nanomaterials interact with plasma will assist in understanding their effects on the biological system. This work presents a systematic study of the protein corona formed from human plasma on 20nm silver and gold nanoparticles with three different surface modifications, including positive and negative surface charges. The results show that all nanoparticles, even those with positive surface modifications, acquire negative charges after interacting with plasma. Approximately 300 proteins are identified on the coronas, while 99 are commonly found on each nanomaterial. The 20 most abundant proteins account for over 80% of the total proteins abundance. Remarkably, the surface charge and core of the nanoparticles, as well as the isoelectric point of the plasma proteins, are found to play significant roles in determining the nanoparticle coronas. Albumin and globulins are present at levels of less than 2% on these nanoparticle coronas. Fibrinogen, which presents in the plasma but not in the serum, preferably binds to negatively charged gold nanoparticles. These observations demonstrate the specific plasma protein binding pattern of silver and gold nanoparticles, as well as the importance of the surface charge and core in determining the protein corona compositions. The potential downstream biological impacts of the corona proteins were also investigated. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Arsenic and mercury levels in human hairs and nails from gold ...

    African Journals Online (AJOL)

    Hair and nail samples obtained from inhabitants of Wassa West District, a major gold mining area in Ghana, were analysed for arsenic (As) and mercury (Hg) using instrumental neutron activation analysis. The samples were irradiated at a thermal neutron flux of 5 x 10P11 Pn cmP-2P sP-1P using the Ghana Research ...

  8. Environmental transformation and distribution of mercury released from gold mining and its implications on human health in Tanzania, studied by nuclear techniques. Highlights and achievements

    International Nuclear Information System (INIS)

    Ikingura, Justinian R.

    2002-01-01

    Tanzania experienced unprecedented rush for gold mining in late 1980s and early 1990s when a similar gold rush was taking place in Latin America and other developing countries because of good gold market prices. The gold rush in Tanzania was also prompted by the socioeconomic and political transformations that were taking place in the country. The liberalization of mining policy and regulations by the government allowed foreign and local private investment in mining and encouraged small-scale mining and gold trade. Because of the liberalization, thousands of local miners, mostly from rural communities, rushed to gold mining for subsistence income. The use of mercury in gold recovery became widespread in Tanzania as a result of the gold rush. From 1992/93, the Department of Geology of the University of Dar es Salaam (UDSM in collaboration with the National Environment Management Council (NEMC) initiated studies to assess the extent of mercury pollution in the country. Further studies on mercury and other heavy metal pollution were undertaken between 1993 and 1997 by UDSM, under a broader project on 'Environmental Aspects of Mining and Industrialization in Tanzania', supported by the Swedish Agency for Research Cooperation with Developing Countries SAREC (Sida/SAREC). The above studies revealed the presence of elevated mercury concentrations in gold-ore tailings and river sediment in several gold mining areas. Studies to evaluate environmental transformation, partition and bioaccumulation of mercury in different environmental matrices and the long-term impact of mercury pollution have not been done. The present research project was initiated to provide scientific database necessary to better understand the environmental behaviour and cycling of mercury in the southwest Lake Victoria goldfields. Such data are necessary in the evaluation of environmental impacts of mercury pollution and in the mitigation of adverse impacts on the ecosystems and human health

  9. Ultrastructural localization of keratin proteins in human skin using low-temperature embedding and the protein A-gold technique.

    Science.gov (United States)

    Warhol, M J; Lucocq, J M; Carlemalm, E; Roth, J

    1985-01-01

    Human skin was embedded in Lowicryl K4M and keratin proteins were localized by incubation with antikeratin antisera, followed by protein A-gold. The antikeratin antisera labeled all intermediate filament (tonofilament) structures in all layers of the epidermis. The association of keratin filaments with hemidesmosomes, desmosomes, and keratohyaline granules was clearly visualized. Desmosomes and keratohyaline granules were not labeled by the antikeratin antisera. No nonfilamentous structures were labeled. The technique described is suitable for studying the distribution of keratin filaments in normal and diseased tissue.

  10. The Study on Activation Strategy of Time-honored Brand

    Directory of Open Access Journals (Sweden)

    Mu Jiankang

    2017-01-01

    Full Text Available Time-honored brands have profound cultural heritage, a large part of glorious time-honored brands has gradually disappeared from the market. Brand activation is the core of management strategic of brand equity as well as the fundamental requirement of time-honored enterprise recovery. This paper constructs the time-honored brand purchase model and finds that consumers nostalgic psychology for the consumer’s perception and buying behavior has a positive effect.

  11. Prioritizing Service to the Academically Talented: The Honors College

    Science.gov (United States)

    Floyd, Deborah L.; Holloway, Alexandria

    2006-01-01

    This chapter describes community college honors programs and courses, emphasizing in particular the Honors College at Miami Dade College in Florida. The chapter discusses pros and cons of honors programs and courses in the context of their appropriateness to the community college mission of open access and egalitarianism. (Contains 1 table.)

  12. Re-Envisioning the Honors Senior Project: Experience as Research

    Science.gov (United States)

    Gustafson, Kevin; Cureton, Zachary

    2014-01-01

    One of the National Collegiate Honors Council (NCHC) Basic Characteristics of a Fully Developed Honors Program is that it creates opportunities for undergraduate research, opportunities that frequently culminate in a senior thesis or capstone project. This article describes how the University of Texas at Arlington Honors College integrated…

  13. The Effect of Honors Courses on Grade Point Averages

    Science.gov (United States)

    Spisak, Art L.; Squires, Suzanne Carter

    2016-01-01

    High-ability entering college students give three main reasons for not choosing to become part of honors programs and colleges; they and/or their parents believe that honors classes at the university level require more work than non-honors courses, are more stressful, and will adversely affect their self-image and grade point average (GPA) (Hill;…

  14. Gold induced apoptsis study

    DEFF Research Database (Denmark)

    Laustsen, Christoffer

    2008-01-01

    Introduction   Cancer cells are highly thermo sensitive. On the basis of an article in Nature the idea arose, for a new non-invasive thermotherapy technique, based on radio frequency inductive heating of nano gold particles in an MR-scanner. Thermotherapy is getting considerably attention...... at the moment, especially in the fields of lasers, they though have some problems concerning the placement of the tumor in the human body. Local heating by MR has tremendous advance in comparison too lasers. The first step is to validate the hypothesis of the inductive heating of the gold nano particles trough...... in silico methods are here proposed for apoptosis studies and for AMG studies.   Methods   MR - heating of high concentration micrometer gold and low concentration nano gold.   CSLM of ethidum bromide stained cell lines, with and witout gold and automated image processing.   AMG gold uptake study...

  15. Benedict Arnold: A Question of Honor.

    Science.gov (United States)

    Nicolosi, Annie; O'Connell, Libby Haight; Rust, Mead

    2003-01-01

    The spring 2003 The Idea Book for Educators highlights television programming from the Arts and Entertainment Network (A&E), the History Channel, and the Biography Channel, with a focus on an A&E original movie premiere, "Benedict Arnold: A Question of Honor." The booklet contains the following materials: "A&E Study…

  16. Gold nanoparticles synthesized by Brassica oleracea (Broccoli) acting as antimicrobial agents against human pathogenic bacteria and fungi

    Science.gov (United States)

    Piruthiviraj, Prakash; Margret, Anita; Krishnamurthy, Poornima Priyadharsani

    2016-04-01

    Production of antimicrobial agents through the synthesis of gold nanoparticles using green technology has been extensively made consistent by various researchers; yet, this study uses the flower bud's aqueous extracts of Brassica oleracea (Broccoli) as a reducing agent for chloroauric acid (1 mM). After 30 min of incubation, synthesis of gold nanoparticles (AuNps) was observed by a change in extract color from pale yellow to purple color. Synthesis of AuNps was confirmed in UV-visible spectroscopy at the range of approximately 560 nm. The SEM analysis showed the average nanoparticles size of 12-22 nm. The antimicrobial activity of AuNps was analyzed by subjecting it to human pathogenic bacteria (Gram-positive Staphylococcus aureus and Gram-negative Klebsiella pneumonia) and fungi (Aspergillus flavus, Aspergillus niger and Candida albicans) using disc diffusion method. The broccoli-synthesized AuNps showed the efficient antibacterial and antifungal activity of above-mentioned microbes. It was confirmed that AuNps have the best antimicrobial agent compared to the standard antibiotics (Gentamicin and Fluconazole). When the concentrations of AuNps were increased (10, 25, and 50 µg/ml), the sensitivity zone also increased for all the tested microbes. The synthesized AuNps are capable of rendering high antimicrobial efficacy and, hence, have a great potential in the preparation of drugs used against major bacterial and fungal diseases in humans.

  17. Sea Lions and Honors Students: More in Common than You May Think

    Science.gov (United States)

    Lindemann-Biolsi, Kristy L.

    2014-01-01

    One can easily find a link between the general principles of learning in relation to both nonhuman and human animals. What may be a more difficult but equally important parallel is how these learning principles are applied to the training of animals and the teaching of honors students. The author considers what teachers can learn from observing…

  18. Mycosynthesis of silver and gold nanoparticles: Optimization, characterization and antimicrobial activity against human pathogens.

    Science.gov (United States)

    Balakumaran, M D; Ramachandran, R; Balashanmugam, P; Mukeshkumar, D J; Kalaichelvan, P T

    2016-01-01

    This study was aimed to isolate soil fungi from Kolli and Yercaud Hills, South India with the ultimate objective of producing antimicrobial nanoparticles. Among 65 fungi tested, the isolate, Bios PTK 6 extracellularly synthesized both silver and gold nanoparticles with good monodispersity. Under optimized reaction conditions, the strain Bios PTK 6 identified as Aspergillus terreus has produced extremely stable nanoparticles within 12h. These nanoparticles were characterized by UV-vis. spectrophotometer, HR-TEM, FTIR, XRD, EDX, SAED, ICP-AES and Zetasizer analyses. A. terreus synthesized 8-20 nm sized, spherical shaped silver nanoparticles whereas gold nanoparticles showed many interesting morphologies with a size of 10-50 nm. The presence and binding of proteins with nanoparticles was confirmed by FTIR study. Interestingly, the myco derived silver nanoparticles exhibited superior antimicrobial activity than the standard antibiotic, streptomycin except against Staphylococcus aureus and Bacillus subtilis. The leakage of intracellular components such as protein and nucleic acid demonstrated that silver nanoparticles damage the bacterial cells by formation of pores, which affects membrane permeability and finally leads to cell death. Further, presence of nanoparticles in the bacterial membrane and the breakage of cell wall were also observed using SEM. Thus, the obtained results clearly reveal that these antimicrobial nanoparticles could be explored as promising candidates for a variety of biomedical and pharmaceutical applications. Copyright © 2015 Elsevier GmbH. All rights reserved.

  19. Radiosensitizing effect of gold nanoparticles in carbon ion irradiation of human cervical cancer cells

    Science.gov (United States)

    Kaur, Harminder; Avasthi, D. K.; Pujari, Geetanjali; Sarma, Asitikantha

    2013-07-01

    Noble metal nanoparticles have received considerable attention in biotechnology for their role in bio sensing due to surface plasmon resonance, medical diagnostics due to better imaging contrast and therapy. The radiosensitization effect of gold nanoparticles (AuNP) has been gaining popularity in radiation therapy of cancer cells. The better depth dose profile of energetic ion beam proves its superiority over gamma radiation for fighting against cancer. In the present work, the glucose capped gold nanoparticles (Glu-AuNP) were synthesised and internalized in the HeLa cells. Transmission electron microscopic analysis of ultrathin sections of Glu-AuNP treated HeLa cells confirmed the internalization of Glu-AuNPs. Control HeLa cells and Glu-AuNp treated HeLa cells were irradiated at different doses of 62 MeV 12C ion beam (LET - 290keV/μm) at BIO beam line of using 15UD Pelletron accelerator at Inter University Accelerator Centre, New Delhi, India. The survival fraction was assessed by colony forming assay which revealed that the dose of carbon ion for 90% cell killing in Glu-AuNP treated HeLa cells and control HeLa cells are 2.3 and 3.2 Gy respectively. This observation shows ˜ 28% reduction of 12C6+ ion dose for Glu-AuNP treated HeLa cells as compared to control HeLa cells.

  20. Radiosensitizing effect of gold nanoparticles in carbon ion irradiation of human cervical cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Harminder; Avasthi, D. K.; Pujari, Geetanjali; Sarma, Asitikantha [Inter University Accelerator Centre, Aruna Asaf Ali Marg, Post box-10502, New Delhi-110067 (India)

    2013-07-18

    Noble metal nanoparticles have received considerable attention in biotechnology for their role in bio sensing due to surface plasmon resonance, medical diagnostics due to better imaging contrast and therapy. The radiosensitization effect of gold nanoparticles (AuNP) has been gaining popularity in radiation therapy of cancer cells. The better depth dose profile of energetic ion beam proves its superiority over gamma radiation for fighting against cancer. In the present work, the glucose capped gold nanoparticles (Glu-AuNP) were synthesised and internalized in the HeLa cells. Transmission electron microscopic analysis of ultrathin sections of Glu-AuNP treated HeLa cells confirmed the internalization of Glu-AuNPs. Control HeLa cells and Glu-AuNp treated HeLa cells were irradiated at different doses of 62 MeV 12C ion beam (LET - 290keV/{mu}m) at BIO beam line of using 15UD Pelletron accelerator at Inter University Accelerator Centre, New Delhi, India. The survival fraction was assessed by colony forming assay which revealed that the dose of carbon ion for 90% cell killing in Glu-AuNP treated HeLa cells and control HeLa cells are 2.3 and 3.2 Gy respectively. This observation shows {approx} 28% reduction of {sup 12}C{sup 6+} ion dose for Glu-AuNP treated HeLa cells as compared to control HeLa cells.

  1. The use of a gold electrode for the determination of amphetamine derivatives and application to their analysis in human urine

    Directory of Open Access Journals (Sweden)

    Nevešćanin Marina M.

    2013-01-01

    Full Text Available The catalytic abilities of gold electrode were tested for the quantitative determination of amphetamine (A and 3,4-methylenedioxy-N-methylamphetamine (MDMA standards by their oxidation using cyclic voltammetry (CV. The value of the oxidative currents of A and MDMA standards at 0.80 V vs. SCE in 0.05 M NaHCO3 at the scan rate of 50 mV/s is linear function of concentration in range of 110.9-258.9 mM and 38.7-229.2 mM, respectively. Square wave voltammetry (SWV revealed linear increase of current with concentration of MDMA (range 30.9-91.6 mM and thus quantitative determination of amphetamine derivates. SWV analysis is successfully performed in spiked urine samples as well. A and MDMA in the presence of sucrose and as a content in illegally produced tablets were also analyzed. The voltammetric determination of A and MDMA derivatives using CV and SWV at gold electrode is a rapid, selective and simple procedure and its accuracy was confirmed with reference method, high performance liquid chromatography (HPLC. The spiked urine samples analysis offers additional possibility for the rapid detection of A and MDMA in human urine.

  2. Mercury use in artisanal small-scale gold mining threatens human health: measures to describe and reduce the health risk

    OpenAIRE

    Steckling, Nadine

    2016-01-01

    **Background:** Mercury is used in more than 70 countries to extract gold in artisanal small-scale gold mining (ASGM). The application of mercury is simple and plays a key role in the livelihood for more than 16 million gold miners. Mercury is added to the crushed ore and builds an amalgam with the gold it contains. The amalgam is then smelted, the mercury evaporates, and gold remains. The amalgam smelting is the main source of mercury exposure in ASGM. ASGM is the largest anthropogenic sourc...

  3. Gold prices

    OpenAIRE

    Joseph G. Haubrich

    1998-01-01

    The price of gold commands attention because it serves as an indicator of general price stability or inflation. But gold is also a commodity, used in jewelry and by industry, so demand and supply affect its pricing and need to be considered when gold is a factor in monetary policy decisions.

  4. Aptamer-functionalized nanoporous gold film for high-performance direct electrochemical detection of bisphenol A in human serum

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Ye, E-mail: zhuye@sdu.edu.cn [School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Zhou, Chuqing; Yan, Xupeng; Yan, Yan [School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Wang, Qiang, E-mail: qiangwang@tjut.edu.cn [Institute of New Energy Materials & Low-Carbon Technologies, Tianjin University of Technology, Tianjin 300384 (China)

    2015-07-09

    Highlights: • NPGF exhibits excellent catalytic activity towards the redox reaction of BPA. • The perfect combination of NPGF with aptamer ensures high sensitivity and selectivity. • The detection limit is determined to be 0.056 ± 0.004 nM BPA. • The detection limit is 15-fold lower than gold nanoparticle-based sensor. • The sensor was successfully applied to detect BPA in human serum samples. - Abstract: In the present work, a highly sensitive and selective biosensor based on aptamer-functionalized nanoporous gold film (NPGF) was successfully developed for direct electrochemical detection of bisphenol A (BPA). NPGF was prepared by dealloying Ag from Au/Ag alloy leaf in concentrated nitric acid. The obtained NPGF was attached onto glassy carbon electrode and then was functionalized with BPA-specific aptamer via the formation of Au−S bond. The fabrication of the sensor was characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. NPGF exhibited excellent electrocatalytic activity towards the redox reaction of BPA, which ensured high sensitivity of the sensor. The aptamer-captured BPA showed a pair of redox peaks around 0.35/0.28 V (vs. Ag/AgCl). The experimental parameters in terms of aptamer concentration, reaction time, pH, and temperature were optimized. The calibration plot showed a linear range from 0.1 nM to 100 nM BPA with a remarkable detection limit of 0.056 ± 0.004 nM BPA. Particularly, the successful application of the developed sensor for the detection of BPA in human serum samples suggests its promising potential for clinical diagnosis.

  5. Cytotoxicity and terminal differentiation of human oral keratinocyte by indium ions from a silver-palladium-gold-indium dental alloy.

    Science.gov (United States)

    Lee, Jung-Hwan; Seo, Sang-Hee; Lee, Sang-Bae; Om, Ji-Yeon; Kim, Kwang-Mahn; Kim, Kyoung-Nam

    2015-02-01

    Dental alloys containing indium (In) have been used in dental restoration for two decades; however, no study has investigated the biological effects of In ions, which may be released in the oral cavity, on human oral keratinocytes. The objective of the present study was to investigate the biological effects of In ions on human oral keratinocyte after confirming their release from a silver-palladium-gold-indium (Ag-Pd-Au-In) dental alloy. As a corrosion assay, a static immersion tests were performed by detecting the released ions in the corrosion solution from the Ag-Pd-Au-In dental alloy using inductively coupled plasma atomic emission spectroscopy. The cytotoxicity and biological effects of In ions were then studied with In compounds in three human oral keratinocyte cell lines: immortalized human oral keratinocyte (IHOK), HSC-2, and SCC-15. Higher concentrations of In and Cu ions were detected in Ag-Pd-Au-In (PAg-Pd-Au, and AgCl deposition occurred on the surface of Ag-Pd-Au-In after a 7-day corrosion test due to its low corrosion resistance. At high concentrations, In ions induced cytotoxicity; however, at low concentrations (∼0.8In(3+)mM), terminal differentiation was observed in human oral keratinocytes. Intracellular ROS was revealed to be a key component of In-induced terminal differentiation. In ions were released from dental alloys containing In, and high concentrations of In ions resulted in cytotoxicity, whereas low concentrations induced the terminal differentiation of human oral keratinocytes via increased intracellular ROS. Therefore, dental alloys containing In must be biologically evaluated for their safe use. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  6. Measuring error rates in genomic perturbation screens: gold standards for human functional genomics.

    Science.gov (United States)

    Hart, Traver; Brown, Kevin R; Sircoulomb, Fabrice; Rottapel, Robert; Moffat, Jason

    2014-07-01

    Technological advancement has opened the door to systematic genetics in mammalian cells. Genome-scale loss-of-function screens can assay fitness defects induced by partial gene knockdown, using RNA interference, or complete gene knockout, using new CRISPR techniques. These screens can reveal the basic blueprint required for cellular proliferation. Moreover, comparing healthy to cancerous tissue can uncover genes that are essential only in the tumor; these genes are targets for the development of specific anticancer therapies. Unfortunately, progress in this field has been hampered by off-target effects of perturbation reagents and poorly quantified error rates in large-scale screens. To improve the quality of information derived from these screens, and to provide a framework for understanding the capabilities and limitations of CRISPR technology, we derive gold-standard reference sets of essential and nonessential genes, and provide a Bayesian classifier of gene essentiality that outperforms current methods on both RNAi and CRISPR screens. Our results indicate that CRISPR technology is more sensitive than RNAi and that both techniques have nontrivial false discovery rates that can be mitigated by rigorous analytical methods. © 2014 The Authors. Published under the terms of the CC BY 4.0 license.

  7. Transport of Gold Nanoparticles by Vascular Endothelium from Different Human Tissues

    Science.gov (United States)

    Gromnicova, Radka; Kaya, Mehmet; Romero, Ignacio A.; Williams, Phil; Satchell, Simon; Sharrack, Basil; Male, David

    2016-01-01

    The selective entry of nanoparticles into target tissues is the key factor which determines their tissue distribution. Entry is primarily controlled by microvascular endothelial cells, which have tissue-specific properties. This study investigated the cellular properties involved in selective transport of gold nanoparticles (nanoparticles than brain endothelium (hCMEC/D3), reflecting their biodistribution in vivo. Nanoparticle uptake and subcellular localisation was quantified by transmission electron microscopy. The rate of internalisation was approximately 4x higher in kidney endothelium than brain endothelium. Vesicular endocytosis was approximately 4x greater than cytosolic uptake in both cell types, and endocytosis was blocked by metabolic inhibition, whereas cytosolic uptake was energy-independent. The cellular basis for the different rates of internalisation was investigated. Morphologically, both endothelia had similar profiles of vesicles and cell volumes. However, the rate of endocytosis was higher in kidney endothelium. Moreover, the glycocalyces of the endothelia differed, as determined by lectin-binding, and partial removal of the glycocalyx reduced nanoparticle uptake by kidney endothelium, but not brain endothelium. This study identifies tissue-specific properties of vascular endothelium that affects their interaction with nanoparticles and rate of transport. PMID:27560685

  8. Uptake and cytotoxicity of citrate-coated gold nanospheres: Comparative studies on human endothelial and epithelial cells

    Directory of Open Access Journals (Sweden)

    Freese Christian

    2012-07-01

    Full Text Available Abstract Background The use of gold nanoparticles (AuNPs for diagnostic applications and for drug and gene-delivery is currently under intensive investigation. For such applications, biocompatibility and the absence of cytotoxicity of AuNPs is essential. Although generally considered as highly biocompatible, previous in vitro studies have shown that cytotoxicity of AuNPs in certain human epithelial cells was observed. In particular, the degree of purification of AuNPs (presence of sodium citrate residues on the particles was shown to affect the proliferation and induce cytotoxicity in these cells. To expand these studies, we have examined if the effects are related to nanoparticle size (10, 11 nm, 25 nm, to the presence of sodium citrate on the particles' surface or they are due to a varying degree of internalization of the AuNPs. Since two cell types are present in the major barriers to the outside in the human body, we have also included endothelial cells from the vasculature and blood brain barrier. Results Transmission electron microscopy demonstrates that the internalized gold nanoparticles are located within vesicles. Increased cytotoxicity was observed after exposure to AuNPs and was found to be concentration-dependent. In addition, cell viability and the proliferation of both endothelial cells decreased after exposure to gold nanoparticles, especially at high concentrations. Moreover, in contrast to the size of the particles (10 nm, 11 nm, 25 nm, the presence of sodium citrate on the nanoparticle surface appeared to enhance these effects. The effects on microvascular endothelial cells from blood vessels were slightly enhanced compared to the effects on brain-derived endothelial cells. A quantification of AuNPs within cells by ICP-AES showed that epithelial cells internalized a higher quantity of AuNPs compared to endothelial cells and that the quantity of uptake is not correlated with the amount of sodium citrate on the

  9. Demography of Honors: The Census of U.S. Honors Programs and Colleges

    Science.gov (United States)

    Scott, Richard I.; Smith, Patricia J.; Cognard-Black, Andrew J.

    2017-01-01

    Beginning in 2013 and spanning four research articles, we have implemented an empirical analysis protocol for honors education that is rooted in demography (Scott; Scott and Smith; Smith and Scott "Growth"; Smith and Scott, "Demography"). The goal of this protocol is to describe the structure and distribution of the honors…

  10. Development and Validation of Gold Nanoprobes for Human SNP Detection Towards Commercial Application

    Science.gov (United States)

    Carlos, Fabio Alexandre Teixeira Ferreira

    Conventional molecular techniques for detection and characterization of relevant nucleic acid (i.e. DNA) sequences are, nowadays, cumbersome, expensive and with reduced portability. The main objective of this dissertation consisted in the optimization and validation of a fast and low-cost colorimetric nanodiagnostic methodology for the detection of single nucleotide polymorphisms (SNPs). This was done considering SNPs associated to obesity of commercial interest for STAB VIDA, and subsequent evaluation of other clinically relevant targets. Also, integration of this methodology into a microfluidic platform envisaging portability and application on points-of-care (POC) was achieved. To warrant success in pursuing these objectives, the experimental work was divided in four sections: i) genetic association of SNPs to obesity in the Portuguese population; ii) optimization and validation of the non-cross-linking approach for complete genotype characterization of these SNPs; iii) incorporation into a microfluidic platform; and iv) translation to other relevant commercial targets. FTO dbSNP rs#:9939609 carriers had higher body mass index (BMI), total body fat mass, waist perimeter and 2.5 times higher risk to obesity. AuNPs functionalized with thiolated oligonucleotides (Au-nanoprobes) were used via the non-cross-linking to validate a diagnostics approach against the gold standard technique - Sanger Sequencing - with high levels of sensitivity (87.50%) and specificity (91.67%). A proof-of-concept POC microfluidic device was assembled towards incorporation of the molecular detection strategy. In conclusion a successful framework was developed and validated for the detection of SNPs with commercial interest for STAB VIDA, towards future translation into a POC device.

  11. Effect of die relief on the seating, fit and retention of cast gold crowns cemented on human teeth.

    Science.gov (United States)

    Lee, H H; Ibbetson, R J

    2000-02-01

    Die relief, by means of a paint-on die spacing material, is the most common method of achieving sufficient space between metal castings and tooth surfaces for cement to flow during seating. Several studies have determined the influence of cementing variables on crowns made for metal and plastic test dies. This study assessed the influence of die relief upon the seating and retention of cast gold crowns constructed for natural human teeth. Standard full crown preparations were made for 10 matched pairs of extracted human third molars, one each of which had been relieved with die spacer of approximately 40 microns thickness. Crowns were made by the indirect technique and were cemented with zinc phosphate cement in a static/dynamic jig. Seating behaviour and vertical discrepancies were measured electronically. Tensile bond strengths were determined in a universal testing machine. Results showed that die relief reduced vertical seating discrepancy associated with cementation by up to 79 microns. Differences between paired relieved and unrelieved samples were significant (p < 0.05). There were no statistically significant differences in tensile bond between paired relieved and unrelieved crowns.

  12. Arsenic and mercury levels in human hairs and nails from gold mining areas in Wassa West District of Ghana

    International Nuclear Information System (INIS)

    Serfor-Armah, Y.; Samlafo, B.V.; Yeboah, P.O.

    2009-01-01

    Hair and nail samples obtained from inhabitants of Wassa District, a major gold mining area in Ghana, were analysed for arsenic (As) and mercury (Hg) using instrumental neutron activation analysis. The samples were irradiated at a thermal neutron flux of 5 x 10 11 n cm -2 s -1 using the Ghana Research Reactor. Concentration of Hg in the hairs ranged from 1.65 to 20.46 μg/g, which were below World Health Organization (WHO) recommended level of 50.00 μg/g for human hair. Mercury concentration in human nail samples ranged from 0.97 to 31.94 μg/g. Arsenic concentrations in human hairs ranged from 0.07 to 0.95 μg/g, while the levels in nail samples ranged from 0.08 to 3.90 μg/g. Generally, levels of As in the hair were less than WHO recommended value of 1.00 μg/g, however, the levels of As in 5 nail samples (FN 11 , FN 20 , FN 28 , TN 9 and TN 16 ) were above the maximum WHO value of 1.80μg/g. The measurement precision specified by the relative standard deviation was within ± 3 %. The accuracy of determination evaluated by analysing certified standard human reference material GBW 09101 was within ± 4 % of the certified value. The levels of As in hair and nail samples of the experimental group were generally higher as compared to the control subject. Similarly, Hg levels in the hair and nail samples in experimental group were also higher compared to the control subject. However, the levels of the toxic elements determined were all below WHO recommended values. (au)

  13. Dietary human exposure to mercury in two artisanal small-scale gold mining communities of northwestern Colombia.

    Science.gov (United States)

    Salazar-Camacho, Carlos; Salas-Moreno, Manuel; Marrugo-Madrid, Siday; Marrugo-Negrete, José; Díez, Sergi

    2017-10-01

    Artisanal and small-scale gold mining (ASGM) is the largest anthropogenic source of mercury pollution worldwide, posing a grave threat to human health. The present study identifies current levels of mercury in the human population from mining areas of the Chocó Department, Colombia, through total mercury (THg) and methylmercury (MeHg) measurements in human hair. Mercury exposure of the local population was assessed in two towns affected by ASGM and was related to different variables of interest. Concentrations of THg in human hair ranged from 0.06 to 17.54ppm and the mean value for the subjects under study was 2.48ppm. Men had significantly higher levels than women in both towns (3.29ppm vs. 0.77ppm). Fish consumption was related to a marked increase of THg in hair, with mean values close to five times higher in frequent fish consumers (5-7 times/week) than in non-fish consumers (4.80ppm vs. 0.90ppm). A multiple linear regression model was fitted successfully (R=0.671) and reveals that gender, fish consumption and location of residence were significant indicators of Hg levels in hair, while no significant relationship was found for age. Approximately 60% of subjects tested had THg levels that exceeded the U.S. Environmental Protection Agency reference dose of 1.0ppm, while 25% surpassed that of the World Health Organization (2.2ppm). Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Assessment of gold nanoparticles on human peripheral blood cells by metabolic profiling with 1H-NMR spectroscopy, a novel translational approach on a patient-specific basis.

    Directory of Open Access Journals (Sweden)

    Martina Palomino-Schätzlein

    Full Text Available Human peripheral blood cells are relevant ex vivo models for characterizing diseases and evaluating the pharmacological effects of therapeutic interventions, as they provide a close reflection of an individual pathophysiological state. In this work, a new approach to evaluate the impact of nanoparticles on the three main fractions of human peripheral blood cells by nuclear magnetic resonance spectroscopy is shown. Thus, a comprehensive protocol has been set-up including the separation of blood cells, their in vitro treatment with nanoparticles and the extraction and characterization of metabolites by nuclear magnetic resonance. This method was applied to assess the effect of gold nanoparticles, either coated with chitosan or supported on ceria, on peripheral blood cells from healthy individuals. A clear antioxidant effect was observed for chitosan-coated gold nanoparticles by a significant increase in reduced glutathione, that was much less pronounced for gold-cerium nanoparticles. In addition, the analysis revealed significant alterations of several other pathways, which were stronger for gold-cerium nanoparticles. These results are in accordance with the toxicological data previously reported for these materials, confirming the value of the current methodology.

  15. Creating Opportunities for Peer Leadership in Honors Education

    Science.gov (United States)

    Leichliter, Marie E.

    2013-01-01

    Honors educators are privileged to work with exceptional students who are also some of the most engaged and motivated students on campus. These students often seek opportunities within their honors experience to study abroad, join community service organizations, conduct research, participate in internships, and develop their leadership skills.…

  16. Building Bridges between Science Courses Using Honors Organic Chemistry Projects

    Science.gov (United States)

    Hickey, Timothy; Pontrello, Jason

    2016-01-01

    Introductory undergraduate science courses are traditionally offered as distinct units without formalized student interaction between classes. To bridge science courses, the authors used three Honors Organic Chemistry projects paired with other science courses. The honors students delivered presentations to mainstream organic course students and…

  17. Turning Points: Improving Honors Student Preparation for Thesis Completion

    Science.gov (United States)

    Patino, Cynthia

    2012-01-01

    This dissertation is an action research study that had as its primary goal to increase retention of honors college students at Arizona State University by implementing an additional advising session during the fifth semester of their academic career. Introducing additional, strategically-timed support for the honors thesis and demystifying the…

  18. Honors Thesis Preparation: Evidence of the Benefits of Structured Curricula

    Science.gov (United States)

    Engel, Steven

    2016-01-01

    A recent study of honors curricula across the nation indicates that 75.6% of honors programs and colleges at four-year institutions have thesis or capstone requirements (Savage and Cognard-Black). In addition to institutions with thesis requirements, many more also have the option for students to complete theses. For example, an earlier study…

  19. Hitting the high notes : Challenge in teaching honors students

    NARCIS (Netherlands)

    Scager, K.

    2013-01-01

    Over the last two decades, honors programs and colleges have mushroomed throughout the Netherlands and elsewhere. Honors programs are intended to challenge the most academically gifted students to develop their full potential.The programs are developed by inspired teachers who are allowed freedom to

  20. An Augustinian Culture of Learning for Interdisciplinary Honors Programs

    Science.gov (United States)

    Ste. Antoine, Tom

    2010-01-01

    Any attempt to discern the purpose of honors education and to integrate it with the unique ethos of a Christian institution can prove to be difficult. Yet, describing and articulating a sense of purpose is essential for an honors program to justify itself. This essay contends that a philosophy of education based on Augustine's…

  1. Human Adipose-Derived Stem Cells Labeled with Plasmonic Gold Nanostars for Cellular Tracking and Photothermal Cancer Cell Ablation.

    Science.gov (United States)

    Shammas, Ronnie L; Fales, Andrew M; Crawford, Bridget M; Wisdom, Amy J; Devi, Gayathri R; Brown, David A; Vo-Dinh, Tuan; Hollenbeck, Scott T

    2017-04-01

    Gold nanostars are unique nanoplatforms that can be imaged in real time and transform light energy into heat to ablate cells. Adipose-derived stem cells migrate toward tumor niches in response to chemokines. The ability of adipose-derived stem cells to migrate and integrate into tumors makes them ideal vehicles for the targeted delivery of cancer nanotherapeutics. To test the labeling efficiency of gold nanostars, undifferentiated adipose-derived stem cells were incubated with gold nanostars and a commercially available nanoparticle (Qtracker), then imaged using two-photon photoluminescence microscopy. The effects of gold nanostars on cell phenotype, proliferation, and viability were assessed with flow cytometry, 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide metabolic assay, and trypan blue, respectively. Trilineage differentiation of gold nanostar-labeled adipose-derived stem cells was induced with the appropriate media. Photothermolysis was performed on adipose-derived stem cells cultured alone or in co-culture with SKBR3 cancer cells. Efficient uptake of gold nanostars occurred in adipose-derived stem cells, with persistence of the luminescent signal over 4 days. Labeling efficiency and signal quality were greater than with Qtracker. Gold nanostars did not affect cell phenotype, viability, or proliferation, and exhibited stronger luminescence than Qtracker throughout differentiation. Zones of complete ablation surrounding the gold nanostar-labeled adipose-derived stem cells were observed following photothermolysis in both monoculture and co-culture models. Gold nanostars effectively label adipose-derived stem cells without altering cell phenotype. Once labeled, photoactivation of gold nanostar-labeled adipose-derived stem cells ablates neighboring cancer cells, demonstrating the potential of adipose-derived stem cells as a vehicle for the delivery of site-specific cancer therapy.

  2. Improving a gold standard: treating human relevance judgments of MEDLINE document pairs

    Directory of Open Access Journals (Sweden)

    Kim Won

    2011-06-01

    Full Text Available Abstract Given prior human judgments of the condition of an object it is possible to use these judgments to make a maximal likelihood estimate of what future human judgments of the condition of that object will be. However, if one has a reasonably large collection of similar objects and the prior human judgments of a number of judges regarding the condition of each object in the collection, then it is possible to make predictions of future human judgments for the whole collection that are superior to the simple maximal likelihood estimate for each object in isolation. This is possible because the multiple judgments over the collection allow an analysis to determine the relative value of a judge as compared with the other judges in the group and this value can be used to augment or diminish a particular judge’s influence in predicting future judgments. Here we study and compare five different methods for making such improved predictions and show that each is superior to simple maximal likelihood estimates.

  3. Gold nanoparticle-based brachytherapy enhancement in choroidal melanoma using a full Monte Carlo model of the human eye.

    Science.gov (United States)

    Asadi, Somayeh; Vaez-zadeh, Mehdi; Masoudi, S Farhad; Rahmani, Faezeh; Knaup, Courtney; Meigooni, Ali S

    2015-09-08

    The effects of gold nanoparticles (GNPs) in 125I brachytherapy dose enhancement on choroidal melanoma are examined using the Monte Carlo simulation technique. Usually, Monte Carlo ophthalmic brachytherapy dosimetry is performed in a water phantom. However, here, the compositions of human eye have been considered instead of water. Both human eye and water phantoms have been simulated with MCNP5 code. These simulations were performed for a fully loaded 16 mm COMS eye plaque containing 13 125I seeds. The dose delivered to the tumor and normal tissues have been calculated in both phantoms with and without GNPs. Normally, the radiation therapy of cancer patients is designed to deliver a required dose to the tumor while sparing the surrounding normal tissues. However, as the normal and cancerous cells absorbed dose in an almost identical fashion, the normal tissue absorbed radiation dose during the treatment time. The use of GNPs in combination with radiotherapy in the treatment of tumor decreases the absorbed dose by normal tissues. The results indicate that the dose to the tumor in an eyeball implanted with COMS plaque increases with increasing GNPs concentration inside the target. Therefore, the required irradiation time for the tumors in the eye is decreased by adding the GNPs prior to treatment. As a result, the dose to normal tissues decreases when the irradiation time is reduced. Furthermore, a comparison between the simulated data in an eye phantom made of water and eye phantom made of human eye composition, in the presence of GNPs, shows the significance of utilizing the composition of eye in ophthalmic brachytherapy dosimetry Also, defining the eye composition instead of water leads to more accurate calculations of GNPs radiation effects in ophthalmic brachytherapy dosimetry.

  4. Honor as Cultural Mindset: Activated Honor Mindset Affects Subsequent Judgment and Attention in Mindset-Congruent Ways

    NARCIS (Netherlands)

    Novin, Sheida; Oyserman, Daphna

    2016-01-01

    Honor values articulate gender roles, the importance of reputation in maintaining one’s place in society, and maintaining respect for the groups one belongs to. In that sense honor provides a template for organizing social interactions and hence may be functional even among people and societies that

  5. Fear of the Loss of Honor: Implications of Honor-Based Violence for the Development of Youth and Their Families

    Science.gov (United States)

    Sedem, Mina; Ferrer-Wreder, Laura

    2015-01-01

    Background: Violence committed against young women, and in some cases young men, who are considered to have violated honor-based norms are reported in several countries, making honor-based violence (HBV) a global concern. This article is an overview of research in this area and summarizes key findings from a Swedish program of research dedicated…

  6. Induction of Chondrogenic Differentiation of Human Mesenchymal Stem Cells by Biomimetic Gold Nanoparticles with Tunable RGD Density.

    Science.gov (United States)

    Li, Jingchao; Li, Xiaomeng; Zhang, Jing; Kawazoe, Naoki; Chen, Guoping

    2017-07-01

    Nanostructured materials have drawn a broad attention for their applications in biomedical fields. Ligand-modified nanomaterials can well mimic the dynamic extracellular matrix (ECM) microenvironments to regulate cell functions and fates. Herein, ECM mimetic gold nanoparticles (Au NPs) with tunable surface arginine-glycine-aspartate (RGD) density are designed and synthesized to induce the chondrogenic differentiation of human mesenchymal stem cells (hMSCs). The biomimetic Au NPs with an average size of 40 nm shows good biocompatibility without affecting the cell proliferation in the studied concentration range. The RGD motifs on Au NPs surface facilitate cellular uptake of NPs into monolayer hMSCs through integrin-mediated endocytosis. The biomimetic NPs have a promotive effect on cartilaginous matrix production and marker gene expression in cell pellet culture, especially for the biomimetic Au NPs with high surface RGD density. This study provides a novel strategy for fabricating biomimetic NPs to regulate cell differentiation, which holds great potentials in tissue engineering and biomedical applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Gold Nanoparticle-Mediated Delivery of Molecules into Primary Human Gingival Fibroblasts Using ns-Laser Pulses: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Judith Krawinkel

    2016-05-01

    Full Text Available Interaction of gold nanoparticles (AuNPs in the vicinity of cells’ membrane with a pulsed laser (λ = 532 nm, τ = 1 ns leads to perforation of the cell membrane, thereby allowing extracellular molecules to diffuse into the cell. The objective of this study was to develop an experimental setting to deliver molecules into primary human gingival fibroblasts (pHFIB-G by using ns-laser pulses interacting with AuNPs (study group. To compare the parameters required for manipulation of pHFIB-G with those needed for cell lines, a canine pleomorphic adenoma cell line (ZMTH3 was used (control group. Non-laser-treated cells incubated with AuNPs and the delivery molecules served as negative control. Laser irradiation (up to 35 mJ/cm2 resulted in a significant proportion of manipulated fibroblasts (up to 85%, compared to non-irradiated cells: p < 0.05, while cell viability (97% was not reduced significantly. pHFIB-G were perforated as efficiently as ZMTH3. No significant decrease of metabolic cell activity was observed up to 72 h after laser treatment. The fibroblasts took up dextrans with molecular weights up to 500 kDa. Interaction of AuNPs and a pulsed laser beam yields a spatially selective technique for manipulation of even primary cells such as pHFIB-G in high throughput.

  8. Electroanalytical Determination of Gemifloxacin Mesylate in Bulk, Tablets and Human Urine Using Gold Nanoparticles Modified Carbon Paste Electrode

    Directory of Open Access Journals (Sweden)

    Ali Attia

    2014-12-01

    Full Text Available A simple, precise, inexpensive and sensitive voltammetric method has been developed for the determination of gemifloxacin mesylate (GEM in the presence of tween 80 in the bulk, farmaceutical dosage forms and human urine at gold nanoparticles modified carbon paste electrode (GNCPE. The electrochemical behavior of GEM has been investigated by using cyclic voltammetry (CV and differential pulse voltammetry (DPV techniques. The electrochemical oxidation of GEM was an irreversible process which exhibited adsorption-diffusion controlled process behavior in Britton-Robinson (BR buffer over the entire pH range of values from 2 to 9. The adsorptive stripping response was evaluated as a function of some variables such as pH, type of surfactant, scan rate and accumulation time. The anodic peak current varied linearly over the range from 8.0 × 10-7 to 2.8 × 10-5 M. The limits of detection and quantification were 7.32 × 10-8 M and 2.44 × 10-7 M, respectively. The relative standard deviations and the percentage recoveries were found in the following ranges: 0.58-1.35% and 99.37-101.76%, respectively.

  9. Integrated Assessment of Artisanal and Small-Scale Gold Mining in Ghana—Part 1: Human Health Review

    Science.gov (United States)

    Basu, Niladri; Clarke, Edith; Green, Allyson; Calys-Tagoe, Benedict; Chan, Laurie; Dzodzomenyo, Mawuli; Fobil, Julius; Long, Rachel N.; Neitzel, Richard L.; Obiri, Samuel; Odei, Eric; Ovadje, Lauretta; Quansah, Reginald; Rajaee, Mozhgon; Wilson, Mark L.

    2015-01-01

    This report is one of three synthesis documents produced via an integrated assessment (IA) that aims to increase understanding of artisanal and small-scale gold mining (ASGM) in Ghana. Given the complexities surrounding ASGM, an IA framework was utilized to analyze economic, social, health, and environmental data, and co-develop evidence-based responses with pertinent stakeholders. The current analysis focuses on the health of ASGM miners and community members, and synthesizes extant data from the literature as well as co-authors’ recent findings regarding the causes, status, trends, and consequences of ASGM in Ghana. The results provide evidence from across multiple Ghanaian ASGM sites that document relatively high exposures to mercury and other heavy metals, occupational injuries and noise exposure. The work also reviews limited data on psychosocial health, nutrition, cardiovascular and respiratory health, sexual health, and water and sanitation. Taken together, the findings provide a thorough overview of human health issues in Ghanaian ASGM communities. Though more research is needed to further elucidate the relationships between ASGM and health outcomes, the existing research on plausible health consequences of ASGM should guide policies and actions to better address the unique challenges of ASGM in Ghana and potentially elsewhere. PMID:25985314

  10. Integrated assessment of artisanal and small-scale gold mining in Ghana--part 1: human health review.

    Science.gov (United States)

    Basu, Niladri; Clarke, Edith; Green, Allyson; Calys-Tagoe, Benedict; Chan, Laurie; Dzodzomenyo, Mawuli; Fobil, Julius; Long, Rachel N; Neitzel, Richard L; Obiri, Samuel; Odei, Eric; Ovadje, Lauretta; Quansah, Reginald; Rajaee, Mozhgon; Wilson, Mark L

    2015-05-13

    This report is one of three synthesis documents produced via an integrated assessment (IA) that aims to increase understanding of artisanal and small-scale gold mining (ASGM) in Ghana. Given the complexities surrounding ASGM, an IA framework was utilized to analyze economic, social, health, and environmental data, and co-develop evidence-based responses with pertinent stakeholders. The current analysis focuses on the health of ASGM miners and community members, and synthesizes extant data from the literature as well as co-authors' recent findings regarding the causes, status, trends, and consequences of ASGM in Ghana. The results provide evidence from across multiple Ghanaian ASGM sites that document relatively high exposures to mercury and other heavy metals, occupational injuries and noise exposure. The work also reviews limited data on psychosocial health, nutrition, cardiovascular and respiratory health, sexual health, and water and sanitation. Taken together, the findings provide a thorough overview of human health issues in Ghanaian ASGM communities. Though more research is needed to further elucidate the relationships between ASGM and health outcomes, the existing research on plausible health consequences of ASGM should guide policies and actions to better address the unique challenges of ASGM in Ghana and potentially elsewhere.

  11. Integrated Assessment of Artisanal and Small-Scale Gold Mining in Ghana—Part 1: Human Health Review

    Directory of Open Access Journals (Sweden)

    Niladri Basu

    2015-05-01

    Full Text Available This report is one of three synthesis documents produced via an integrated assessment (IA that aims to increase understanding of artisanal and small-scale gold mining (ASGM in Ghana. Given the complexities surrounding ASGM, an IA framework was utilized to analyze economic, social, health, and environmental data, and co-develop evidence-based responses with pertinent stakeholders. The current analysis focuses on the health of ASGM miners and community members, and synthesizes extant data from the literature as well as co-authors’ recent findings regarding the causes, status, trends, and consequences of ASGM in Ghana. The results provide evidence from across multiple Ghanaian ASGM sites that document relatively high exposures to mercury and other heavy metals, occupational injuries and noise exposure. The work also reviews limited data on psychosocial health, nutrition, cardiovascular and respiratory health, sexual health, and water and sanitation. Taken together, the findings provide a thorough overview of human health issues in Ghanaian ASGM communities. Though more research is needed to further elucidate the relationships between ASGM and health outcomes, the existing research on plausible health consequences of ASGM should guide policies and actions to better address the unique challenges of ASGM in Ghana and potentially elsewhere.

  12. Human exposure and risk assessment associated with mercury contamination in artisanal gold mining areas in the Brazilian Amazon.

    Science.gov (United States)

    Castilhos, Zuleica; Rodrigues-Filho, Saulo; Cesar, Ricardo; Rodrigues, Ana Paula; Villas-Bôas, Roberto; de Jesus, Iracina; Lima, Marcelo; Faial, Kleber; Miranda, Antônio; Brabo, Edilson; Beinhoff, Christian; Santos, Elisabeth

    2015-08-01

    Mercury (Hg) contamination is an issue of concern in the Amazon region due to potential health effects associated with Hg exposure in artisanal gold mining areas. The study presents a human health risk assessment associated with Hg vapor inhalation and MeHg-contaminated fish ingestion, as well as Hg determination in urine, blood, and hair, of human populations (about 325 miners and 321 non-miners) from two gold mining areas in the Brazilian Amazon (São Chico and Creporizinho, Pará State). In São Chico and Creporizinho, 73 fish specimens of 13 freshwater species, and 161 specimens of 11 species, were collected for total Hg determination, respectively. The hazard quotient (HQ) is a risk indicator which defines the ratio of the exposure level and the toxicological reference dose and was applied to determine the threat of MeHg exposure. The mean Hg concentrations in fish from São Chico and Creporizinho were 0.83 ± 0.43 and 0.36 ± 0.33 μg/g, respectively. More than 60 and 22 % of fish collected in São Chico and Creporizinho, respectively, were above the Hg limit (0.5 μg/g) recommended by WHO for human consumption. For all sampling sites, HQ resulted from 1.5 to 28.5, except for the reference area. In Creporizinho, the values of HQ are close to 2 for most sites, whereas in São Chico, there is a hot spot of MeHg contamination in fish (A2-São Chico Reservoir) with the highest risk level (HQ = 28) associated with its human consumption. Mean Hg concentrations in urine, blood, and hair samples indicated that the miners group (in São Chico: urine = 17.37 μg/L; blood = 27.74 μg/L; hair = 4.50 μg/g and in Creporizinho: urine = 13.75 μg/L; blood = 25.23 μg/L; hair: 4.58 μg/g) was more exposed to mercury compared to non-miners (in São Chico: urine = 5.73 μg/L; blood = 16.50 μg/L; hair = 3.16 μg/g and in Creporizinho: urine = 3.91 μg/L; blood = 21.04 μg/L, hair = 1.88 μg/g). These high Hg levels (found

  13. Environmental transformation and distribution of mercury released from gold mining and its implications on human health in Tanzania, studied by nuclear techniques

    International Nuclear Information System (INIS)

    Ikingura, Justinian R.

    2002-01-01

    The dispersion and transformation of mercury in the southwest Lake Victoria gold fields was investigated through field and laboratory studies in order to evaluate the environmental impact and human health risks due to mercury pollution from small-scale gold mining in Tanzania. River sediment, gold-ore tailings, fish, and lichens were analyzed for their mercury content to determine mercury contamination levels. Mercury concentrations in the tailings from Rwamagaza mine were in the range of 165 to 232 mg/kg while at the Mugusu mine the maximum concentration was 6 mg/kg in the river sediment contaminated by the tailings. The dispersion of mercury along the Mabubi River downstream of the gold-ore processing site at the Mugusu mine decreased rapidly to less than 0.5 mg/kg at a distance of 4 km, and less than 0.1 mg/kg at 9 km. Granulometrical analysis of mercury distribution indicated highest mercury concentrations to be associated with the grain size fraction <212 mm in the sediment. Total mercury concentrations in eight fish species from the Lake Victoria at Nungwe Bay were generally very low and varied from 2 to 34, μg/kg (w.w). The lowest concentrations were found in Tilapia and the highest in Nile perch. The percentage of methylmercury in the fish muscle ranged from 65 to 97%. These results suggest that mercury contamination from gold mining operations in the southwest Lake Victoria goldfields has not led to any significant increase in environmental methylmercury levels that could be reflected in high mercury concentrations in the fish. Based on these results, fish consumption from the Nungwe Bay area of the Lake Victoria does not pose any human health risks on account of very low mercury levels in the fish at present. Mercury concentrations in two lichen species, Parmelia and Usnea, in the Geita Forest Reserve around the Mugusu mine ranged from 0.10 to 3.10 μg/g (d.w.). The mercury concentration in the lichens decreased away from the mine village, indicating the

  14. Gold Nanoparticles Promote Proliferation of Human Periodontal Ligament Stem Cells and Have Limited Effects on Cells Differentiation

    Directory of Open Access Journals (Sweden)

    Chen Li

    2016-01-01

    Full Text Available Gold nanoparticles (AuNPs had been widely applied in the practice and advancement of chemistry, biology, and medicine due to facility of synthesis and versatility in surface functionalization. Recent studies had shown that AuNPs can be applied to cells, affecting cellular physiological processes such as proliferation and differentiation. In this study, four diameters of AuNPs (20, 40, 60, and 80 nm were cocultured with human periodontal ligament cells (hPDLCs at six different concentrations. The optimal size and concentration of AuNPs were selected to treat human periodontal ligament stem cells (hPDLSCs to evaluate proliferation. Moreover, the influence of AuNPs on multiple differentiation capacity of hPDLSCs was clarified. The results revealed that AuNPs (60 nm, 56 μM can effectively promote the proliferation of hPDLCs/hPDLSCs in vitro, slightly enhance osteoblastic differentiation, and have no effect on adipogenic differentiation. In addition, the expression of COL-1, Runx2, BSP, and OCN was upregulated in the presence of AuNPs (60 nm, 56 μM. These results indicated that AuNPs (60 nm, 56 μM can effectively promote the proliferation of hPDLCs/hPDLSCs and have no significant effect on the differentiation of hPDLSCs. These results provide an insight on the advantage of implementing of AuNPs on hPDLSCs culture and expose the influence of these materials on periodontal tissue engineering.

  15. A human endogenous protein exerts multi-role biomimetic chemistry in synthesis of paramagnetic gold nanostructures for tumor bimodal imaging.

    Science.gov (United States)

    Yang, Weitao; Wu, Xiaoli; Dou, Yan; Chang, Jin; Xiang, Chenyang; Yu, Jiani; Wang, Jun; Wang, Xiuli; Zhang, Bingbo

    2018-04-01

    Protein-mediated biomimetic nanoparticles because of simplicity of their synthesis, subdued nonspecific adsorption, improved pharmacokinetics, and biocompatibility have been receiving increasing attention recently. Nevertheless, only a handful of proteins have been developed for biomimetic synthesis. Worse still, most of them are constrained on single-function usages in chemistry. Exploring new functional proteins, especially those with multi-dentate moieties for multi-role biomimetic chemistry, still remains a substantial challenge. Here, we report on a human endogenous protein, glutathione S-transferase (GST), with favorable amino acid motifs, that has innate talents in incubating high quality gold nanoparticles without adding reducing agents at physiological temperature, and particularly can further anchor gadolinium ions without adding extra chelators. The resultant paramagnetic AuNPs@GST Gd exhibits highly crystallization and uniform size of ca. 10 nm. Compared with clinical contrast agents (Iopamidol, Magnevist), AuNPs@GST Gd shows better imaging performance (e.g. enhanced relaxivity and larger X-ray attenuation efficiency) with clear evidence from Monte Carlo simulation and in vitro experimental results. Further in vivo imaging demonstrates good tumor targeting and clearance of AuNPs@GST Gd without obvious systemic toxicity. Particularly, low immunogenicity of AuNPs@GST Gd is certified by immunological status evaluation of T cells after stimulated with them. This study for the first time demonstrates the manipulation of a human protein for multi-role biomimetic chemistry depending on its unique amino acid motifs and its incorporation into a synthetic agent for potentially addressing some critical issues in cancer nanotheranostics such as synthetic methodology, biocompatibility, function integration, targeting, and immunogenicity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Gold-silica nanocomposites for the detection of human ovarian cancer cells: a preliminary study

    International Nuclear Information System (INIS)

    Mishra, Y K; Mohapatra, S; Avasthi, D K; Kabiraj, D; Lalla, N P; Pivin, J C; Sharma, Himani; Kar, Rajarshi; Singh, Neeta

    2007-01-01

    We report the structural and optical properties of Au nanoparticles embedded in a silica matrix synthesized by atom beam co-sputtering. The presence of surface plasmon resonant absorption indicates the formation of Au nanoparticles. Transmission electron microscopy (TEM) studies show the presence of Au nanoparticles with an average size ranging from ∼1.8 to 5.4 nm with narrow size distributions depending on the relative areas of Au and SiO 2 . We discuss the process of nucleation and growth of Au nanoparticles in the nanocomposite films formed by co-sputtering. The present method of nanoparticle synthesis is compared with other ion beam based techniques such as ion implantation and ion beam mixing. Preliminary experiments for the detection of human ovarian cancer cells using these Au nanoparticles are described

  17. Gold Returns

    OpenAIRE

    Robert J. Barro; Sanjay P. Misra

    2013-01-01

    From 1836 to 2011, the average real rate of price change for gold in the United States is 1.1% per year and the standard deviation is 13.1%, implying a one-standard-deviation confidence band for the mean of (0.1%, 2.1%). The covariances of gold's real rate of price change with consumption and GDP growth rates are small and statistically insignificantly different from zero. These negligible covariances suggest that gold's expected real rate of return--which includes an unobserved dividend yiel...

  18. Planning and implementing an honors degree in environmental science curricula: a case study from the University of Delaware, USA

    Science.gov (United States)

    Levia, Delphis

    2015-04-01

    Environmental degradation is undermining the sustainability of our planet. The multi-faceted nature of environmental stressors, which inherently couples human-environment interactions across space and time, necessitates that we train environmental scientists holistically within an interdisciplinary framework. Recruiting top-notch honors students to major in the environmental sciences is a critical step to ensure that we have the human capital to tackle complicated environmental problems successfully. Planning and implementing an honors degree is no trivial task. Based upon a recently completed and implemented set of programmatic revisions*, this poster showcases a successful example of an honors curriculum in environmental science to recruit and educate dynamic thinkers capable of improving the quality of our environment. The interdisciplinary environmental science program at the University of Delaware emphasizes the cross-cutting among earth's spheres through a core set of courses which employ a quantitative approach which is supplemented by several environmental policy courses. The core is coupled with six different thematic concentrations (students choose one) which permit the student to delve into a particular area of environmental science. The honors component of the degree consists of twelve additional credits. These credits are met through a specially designed introductory environmental course, a field experience requiring data collection, analysis, and write-up, a capstone course, and one other environmentally related course. The environmental sciences honors curriculum outlined in this poster may serve as a useful guide to others wishing to establish an honors program of their own in environmental science to recruit and prepare the next generation to mitigate environmental degradation. -------------- * Please note that the planning process for the environmental programs was and is the collective effort of many dedicated people. Current members of the

  19. DNA-gadolinium-gold nanoparticles for in vivo T1 MR imaging of transplanted human neural stem cells.

    Science.gov (United States)

    Nicholls, Francesca J; Rotz, Matthew W; Ghuman, Harmanvir; MacRenaris, Keith W; Meade, Thomas J; Modo, Michel

    2016-01-01

    The unambiguous imaging of transplanted cells remains a major challenge to understand their biological function and therapeutic efficacy. In vivo imaging of implanted cells is reliant on tagging these to differentiate them from host tissue, such as the brain. We here characterize a gold nanoparticle conjugate that is functionalized with modified deoxythymidine oligonucleotides bearing Gd(III) chelates and a red fluorescent Cy3 moiety to visualize in vivo transplanted human neural stem cells. This DNA-Gd@Au nanoparticle (DNA-Gd@AuNP) exhibits an improved T1 relaxivity and excellent cell uptake. No significant effects of cell uptake have been found on essential cell functions. Although T1 relaxivity is attenuated within cells, it is sufficiently preserved to afford the in vivo detection of transplanted cells using an optimized voxel size. In vivo MR images were corroborated by a post-mortem histological verification of DNA-Gd@AuNPs in transplanted cells. With 70% of cells being correctly identified using the DNA-Gd-AuNPs indicates an overall reliable detection. Less than 1% of cells were false positive for DNA-Gd@AuNPs, but a significant number of 30% false negatives reveals a dramatic underestimation of transplanted cells using this approach. DNA-Gd@AuNPs therefore offer new opportunities to visualize transplanted cells unequivocally using T1 contrast and use cellular MRI as a tool to derive biologically relevant information that allows us to understand how the survival and location of implanted cells determines therapeutic efficacy. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Human health risks from metals and metalloid via consumption of food animals near gold mines in Tarkwa, Ghana: Estimation of the daily intakes and target hazard quotients (THQs)

    OpenAIRE

    Bortey-Sam, Nesta; Nakayama, Shouta M. M.; Ikenaka, Yoshinori; Akoto, Osei; Baidoo, Elvis; Yohannes, Yared Beyene; Mizukawa, Hazuki; Ishizuka, Mayumi

    2015-01-01

    Heavy metal and metalloid contamination in food resulting from mining is of major concern due to the potential risk involved. Food consumption is the most likely route of human exposure to metals. This study was therefore to assess metals in different organs and different animal species near gold mines used for human consumption (free-range chicken, goat and sheep) in Tarkwa, Ghana, and to estimate the daily intake and health risk. The concentrations of Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, and...

  1. 34 CFR 654.1 - What is the Robert C. Byrd Honors Scholarship Program?

    Science.gov (United States)

    2010-07-01

    ... 34 Education 3 2010-07-01 2010-07-01 false What is the Robert C. Byrd Honors Scholarship Program...) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION ROBERT C. BYRD HONORS SCHOLARSHIP PROGRAM General § 654.1 What is the Robert C. Byrd Honors Scholarship Program? Under the Robert C. Byrd Honors...

  2. A Tradition Unlike Any Other: Research on the Value of an Honors Senior Thesis

    Science.gov (United States)

    Banks, H. Kay

    2016-01-01

    An honors senior thesis introduces students into a world of scholarship and professional activity in a way that no single course, either semester- or year-long, can do (Anderson, Lyons, and Weiner). Many honors educators consider honors thesis work to be the defining honors experience. For graduate schools, employers, and the students themselves,…

  3. Cytotoxic activity of biosynthesized gold nanoparticles with an extract of the red seaweed Corallina officinalis on the MCF-7 human breast cancer cell line.

    Science.gov (United States)

    El-Kassas, Hala Yassin; El-Sheekh, Mostafa M

    2014-01-01

    Nano-biotechnology is recognized as offering revolutionary changes in the field of cancer therapy and biologically synthesized gold nanoparticles are known to have a wide range of medical applications. Gold nanoparticles (GNPs) were biosynthesized with an aqueous extract of the red alga Corallina officinalis, used as a reducing and stabilizing agent. GNPs were characterized using UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive analysis (EDX) and Fourier transform infra-red (FT-IR) spectroscopy and tested for cytotoxic activity against human breast cancer (MCF-7) cells cultured in Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum, considering their cytotoxicty and effects on cellular DNA. The biosynthesized GNPs were 14.6 ± 1 nm in diameter. FT-IR analysis showed that the hydroxyl functional group from polyphenols and carbonyl group from proteins could assist in formation and stabilization. The GNPs showed potent cytotoxic activity against MCF-7 cells, causing necrosis at high concentrations while lower concentrations were without effect as indicated by DNA fragmentation assay. The antitumor activity of the biosynthesized GNPs from the red alga Corallina officinalis against human breast cancer cells may be due to the cytotoxic effects of the gold nanoparticles and the polyphenolcontent of the algal extract.

  4. And the Top Honor Goes to Voc Ed.

    Science.gov (United States)

    Hettinger, James

    1998-01-01

    Ray Chelewski is the first vocational-technical educator to win Walt Disney's top teaching honor. Chelewski is an agriculture teacher at the Presque Isle Regional Technology Center in northeast Maine. (JOW)

  5. Symposium in Honor of Minoru M. Freund

    CERN Document Server

    Langhoff, Stephanie

    2014-01-01

    The presentations at this NASA-hosted Symposium in honor of Mino Freund will touch upon the fields, to which his prolific mind has made significant contributions. These include low temperature physics, cosmology, and nanotechnology with its wide-ranging applicability to material science, neuroscience, Earth sciences and satellite technology.  To learn more about Mino’s career you can download the "Tribute" , which outlines his journey from (i) low-temperature physics and superconductivity at the ETH Zürich to (ii) building one remarkable milliKelvin refrigerator for the US-Japan IRTS mission at UC Berkeley and ISAS in Japan to (iii) a decade in cosmology, to (iv) being on the micro-bolometer team at NASA Goddard for the HAWC instrument on SOFIA, to (v) developing at AFRL the nanotechnology portfolio for the entire Air Force.  This was followed by six years at the NASA Ames Research Center, where Mino formulated his far-ahead ideas about swarms of capable nanosats circling the Earth, which have since star...

  6. Design, Synthesis, and Use of Peptides Derived from Human Papillomavirus L1 Protein for the Modification of Gold Electrode Surfaces by Self-Assembled Monolayers.

    Science.gov (United States)

    Lara Carrillo, John Alejandro; Fierro Medina, Ricardo; Manríquez Rocha, Juan; Bustos Bustos, Erika; Insuasty Cepeda, Diego Sebastián; García Castañeda, Javier Eduardo; Rivera Monroy, Zuly Jenny

    2017-11-14

    In order to obtain gold electrode surfaces modified with Human Papillomavirus L1 protein (HPV L1)-derived peptides, two sequences, SPINNTKPHEAR and YIK, were chosen. Both have been recognized by means of sera from patients infected with HPV. The molecules, Fc-Ahx-SPINNTKPHEAR, Ac-C- Ahx -(Fc)KSPINNTKPHEAR, Ac-C- Ahx -SPINNTKPHEAR(Fc)K, C- Ahx -SPINNTKPHEAR, and (YIK)₂- Ahx -C, were designed, synthesized, and characterized. Our results suggest that peptides derived from the SPINNTKPHEAR sequence, containing ferrocene and cysteine residues, are not stable and not adequate for electrode surface modification. The surface of polycrystalline gold electrodes was modified with the peptides C-Ahx-SPINNTKPHEAR or (YIK)₂-Ahx-C through self-assembly. The modified polycrystalline gold electrodes were characterized via infrared spectroscopy and electrochemical measurements. The thermodynamic parameters, surface coverage factor, and medium pH effect were determined for these surfaces. The results indicate that surface modification depends on the peptide sequence (length, amino acid composition, polyvalence, etc.). The influence of antipeptide antibodies on the voltammetric response of the modified electrode was evaluated by comparing results obtained with pre-immune and post-immune serum samples.

  7. Alzheimer's disease biomarkers detection in human samples by efficient capturing through porous magnetic microspheres and labelling with electrocatalytic gold nanoparticles

    Czech Academy of Sciences Publication Activity Database

    de la Escosura-Muniz, A.; Plichta, Zdeněk; Horák, Daniel; Merkoci, A.

    2015-01-01

    Roč. 67, 15 May (2015), s. 162-169 ISSN 0956-5663 R&D Projects: GA MŠk 7E12053 EU Projects: European Commission(XE) 246513 - NADINE Institutional support: RVO:61389013 Keywords : porous magnetic microspheres * gold nanoparticles * electrochemical immunoassay Subject RIV: CD - Macromolecular Chemistry Impact factor: 7.476, year: 2015

  8. Gold Museum

    OpenAIRE

    Efraín Sánchez Cabra

    2003-01-01

    On 22 december 1939, the Banco de la República, the Central Bank of Colombia, purchased a 23.5 centimetres high pre-Columbian gold arte fact weighing 777·7 grams that was to become the Gold M useum's foundation stone. Described as a Quimbaya poporo, it is a masterpiece of pre-Hispanic goldwork, an object of beauty whose brightly burnished body and neck, crowned with four sphere-like or naments, rest on an exquisite cast metal tiligree base and which seems to ftoat in a space of its own. The b...

  9. Gold nanoparticles promote osteogenic differentiation in human adipose-derived mesenchymal stem cells through the Wnt/β-catenin signaling pathway

    Directory of Open Access Journals (Sweden)

    Choi SY

    2015-07-01

    Full Text Available Seon Young Choi,1 Min Seok Song,1 Pan Dong Ryu,1 Anh Thu Ngoc Lam,2 Sang-Woo Joo,2 So Yeong Lee1 1Laboratory of Veterinary Pharmacology, Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, 2Department of Chemistry, Soongsil University, Seoul, South Korea Abstract: Gold nanoparticles (AuNPs are attractive materials for use in biomedicine due to their physical properties. Increasing evidence suggests that several nanoparticles induce the differentiation of human mesenchymal stem cells into osteoblasts and adipocytes. In this study, we hypothesized that chitosan-conjugated AuNPs promote the osteogenic differentiation of human adipose-derived mesenchymal stem cells. For the evaluation of osteogenic differentiation, alizarin red staining, an alamarBlue® assay, and a quantitative real-time polymerase chain reaction analysis were performed. In order to examine specific signaling pathways, immunofluorescence and a western blotting assay were performed. Our results demonstrate that chitosan-conjugated AuNPs increase the deposition of calcium content and the expression of marker genes related to osteogenic differentiation in human adipose-derived mesenchymal stem cells at nontoxic concentrations. These results indicate that chitosan-conjugated AuNPs promote osteogenesis through the Wnt/β-catenin signaling pathway. Therefore, chitosan-conjugated AuNPs can be used as a reagent for promoting bone formation. Keywords: chitosan-conjugated gold nanoparticle, mineralization, nonphosphorylated beta-catenin

  10. Human β-defensin 3-combined gold nanoparticles for enhancement of osteogenic differentiation of human periodontal ligament cells in inflammatory microenvironments

    Directory of Open Access Journals (Sweden)

    Zhou J

    2018-01-01

    Full Text Available Jing Zhou,1 Yangheng Zhang,1 Lingjun Li,1 Huangmei Fu,2 Wenrong Yang,2 Fuhua Yan1 1Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, People’s Republic of China; 2School of Life and Environmental Science, Centre for Chemistry and Biotechnology, Deakin University, Geelong, VIC, Australia Objective: It is a great challenge to absorb and conduct biophysicochemical interactions at the nano-bio interface. Peptides are emerging as versatile materials whose function can be programmed to perform specific tasks. Peptides combined nanoparticles might be utilized as a new approach of treatment. Human β-defensin 3 (hBD3, possesses both antimicrobial and proregeneration properties. Gold nanoparticles (AuNPs have shown promising applications in the field of tissue engineering. However, the coordinating effects of AuNPs and hBD3 on human periodontal ligament cells (hPDLCs remain unknown. In this study, we systematically investigated whether AuNPs and hBD3 would be able to coordinate and enhance the osteogenic differentiation of hPDLCs in inflammatory microenvironments, and the underlying mechanisms was explored. Methods: hPDLCs were stimulated with E. coli-LPS, hBD3 and AuNPs. Alkaline phosphatase (ALP and alizarin red S staining were used to observe the effects of hBD3 and AuNPs on the osteogenic differentiation of hPDLCs. Real-time PCR and western blot were performed to evaluate the osteogenic differentiation and Wnt/β-catenin signaling pathway related gene and protein expression.Results: In the inflammatory microenvironments stimulated by E. coli-LPS, we found that AuNPs and hBD3 increased the proliferation of hPDLCs slightly. In addition, hBD3-combined AuNPs could significantly enhance ALP activities and mineral deposition in vitro. Meanwhile, we observed that the osteogenic differentiation-related gene and protein expressions of ALP, collagenase-I (COL-1 and runt-related transcription factor 2 (Runx-2 were

  11. Green Gold

    International Nuclear Information System (INIS)

    Salamandra Martinez, Carlos

    2004-01-01

    The main purpose of this work is to offer a general panoramic of the processes or experiences pilot that are carried out in the Project Green Gold, as strategy of environmental sustainability and organizational invigoration in Choco, especially in the 12 communities of the municipalities of Tado and Condoto. It is also sought to offer a minimum of information on the techniques of handmade production and to show the possibilities to carry out in a rational way the use and use of the natural resources. The Project Green Gold is carried out by the Corporation Green Gold (COV) and co-financed with resources of international and national character, the intervention of the financial resources it achievement mainly for the use of clean processes in the extraction stages and metals benefit. The project is centered primarily in the absence of use of products or toxic substances as the mercury, fair trade, organizational invigoration, execution of 11 approaches and certification of the metals Gold and Platinum. The COV, it has come executing the proposal from the year 2001 with the premise of contributing to the balance between the rational exploitation of the natural resources and the conservation of the environment in the Choco. In the project they are used technical handmade characteristic of the region framed inside the mining activity and production activities are diversified in the productive family units. Those producing with the support of entities of juridical character, specify the necessary game rules for the extraction and products commercialization

  12. Honor killing attitudes amongst adolescents in Amman, Jordan.

    Science.gov (United States)

    Eisner, Manuel; Ghuneim, Lana

    2013-01-01

    The present study examines attitudes towards honor crimes amongst a sample of 856 ninth grade students (mean age = 14.6, SD = 0.56) from 14 schools in Amman, Jordan. Descriptive findings suggest that about 40% of boys and 20% of girls believe that killing a daughter, sister, or wife who has dishonored the family can be justified. A number of theoretically meaningful predictors were examined: Findings suggest that attitudes in support of honor killings are more likely amongst adolescents who have collectivist and patriarchal world views, believe in the importance of female chastity amongst adolescents, and morally neutralize aggressive behavior in general. Findings for parental harsh discipline are mixed: While the father's harsh discipline is predictive of honor killing attitudes, the mother's behavior is not. Furthermore, support for honor killing is stronger amongst male adolescents and adolescents for low education backgrounds. After controlling for other factors religion and the intensity of religious beliefs are not associated with support for honor killings. Models were tested separately for male and female respondents and suggested no systematic differences in predictors. Limitations and implications are discussed. © 2013 Wiley Periodicals, Inc.

  13. Environmental transformation and distribution of mercury released from gold mining and its implications on human health in Tanzania, studied by nuclear techniques

    International Nuclear Information System (INIS)

    Ikingura, Justinian R.

    2001-01-01

    The catchment areas of Lake Victoria in Tanzania are impacted by mercury contamination from small-scale gold mining activities. A preliminary survey of the mercury contamination has indicated in some cases mercury concentrations that are higher than background levels in soil and river sediment downstream of the mining areas. Average mercury concentration in contaminated soil is in the order of 3.4 mg/kg whereas in river sediment the concentration is about 4.9 mg/kg. Mercury concentrations in fish from a few areas of the Lake Victoria close to gold mining areas are in the range of 2-20 ppb. These fish mercury concentrations are surprisingly low considering the extent of mercury contamination in the Lake Victoria catchment. The dynamics of mercury cycling and their long-term impact on mercury levels in fish and other aquatic organisms in the Lake Victoria gold fields still need to be clarified. Research activities for the first year (2000) will concentrate on the determination of total mercury distribution patterns among soil, river water, sediment, and biota (fish, and other aquatic biota) in two areas (Mugusu-Nungwe Bay and Imweru-Bukombe Bay) of the Lake Victoria gold fields. The relationships between local tropical soil-sediment- and water-chemistry and the distribution of mercury in the contaminated areas will be investigated. Data from this work will be used in the identification and selection of suitable bio-monitors for mercury contamination and human health risk assessment in the study areas. In the second year, the project will focus mainly on methylmercury production and partition between sediment, water and biota in contaminated local tropical sediments. The main factors influencing the methylation and distribution of mercury species will be evaluated in laboratory experiments and extrapolated to environmental conditions. The results of the project will have important implications in mercury pollution monitoring, mitigation, and health risk assessment not

  14. Gold Nanoparticles Cytotoxicity

    Science.gov (United States)

    Mironava, Tatsiana

    Over the last two decades gold nanoparticles (AuNPs) have been used for many scientific applications and have attracted attention due to the specific chemical, electronic and optical size dependent properties that make them very promising agents in many fields such as medicine, imagine techniques and electronics. More specifically, biocompatible gold nanoparticles have a huge potential for use as the contrast augmentation agent in X-ray Computed Tomography and Photo Acoustic Tomography for early tumor diagnostic as well these nanoparticles are extensively researched for enhancing the targeted cancer treatment effectiveness such as photo-thermal and radiotherapy. In most biomedical applications biocompatible gold nanoparticles are labeled with specific tumor or other pathology targeting antibodies and used for site specific drug delivery. However, even though gold nanoparticles poses very high level of anti cancer properties, the question of their cytotoxicity ones they are released in normal tissue has to be researched. Moreover, the huge amount of industrially produced gold nanoparticles raises the question of these particles being a health hazard, since the penetration is fairly easy for the "nano" size substances. This study focuses on the effect of AuNPs on a human skin tissue, since it is fall in both categories -- the side effects for biomedical applications and industrial workers and users' exposure during production and handling. Therefore, in the present project, gold nanoparticles stabilized with the biocompatible agent citric acid were generated and characterized by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). The cytotoxic effect of AuNPs release to healthy skin tissue was modeled on 3 different cell types: human keratinocytes, human dermal fibroblasts, and human adipose derived stromal (ADS) cells. The AuNPs localization inside the cell was found to be cell type dependent. Overall cytotoxicity was found to be dependent

  15. Gold nanoparticle labeling of cells is a sensitive method to investigate cell distribution and migration in animal models of human disease.

    Science.gov (United States)

    Menk, Ralf Hendrik; Schültke, Elisabeth; Hall, Christopher; Arfelli, Fulvia; Astolfo, Alberto; Rigon, Luigi; Round, Adam; Ataelmannan, Khalid; MacDonald, Sarah Rigley; Juurlink, Bernhard H J

    2011-10-01

    The ability to track cells in small-animal models of human disease is important because it gives the potential to improve our understanding of the processes of disease progression as well as our understanding of the therapeutic effects of interventions. In this study gold nanoparticles have been used as a permanent marker of implanted normal and malignant cell grafts in combination with a suitable x-ray apparatus. Using x-ray computed tomography the micrometric three-dimensional distribution of these marked cells could be displayed with penetration depth, high cell sensitivity and high spatial resolution in rodent models of human diseases. In principle the method allows quantification of cell numbers at any anatomical location over time in small animals. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Obituary: Thomas Gold, 1920-2004

    Science.gov (United States)

    Dermott, Stanley F.

    2004-12-01

    Thomas "Tommy" Gold died of heart disease at Cayuga Medical Center, Ithaca NY on 22 June 2004 at the age of 84. He will be remembered as one of the most interesting, dynamic and influential scientists of his generation. Tommy's paradigm-changing ideas in astronomy and planetary science, while original and bold, were also highly controversial. With his radical work on the origin of natural gas and petroleum, the controversy is likely to continue. Tommy was born in Vienna, Austria on 22 May 1920, moving with his family to Berlin at age 10 and then, after the rise of Hitler in 1933, to England. His parents were Josephine (nee Martin) and Maximillian Gold, a successful steel magnate. Tommy was educated at Zuoz College in Switzerland where he became an expert skier and developed an athletic prowess that he maintained throughout his life, winning a NASTAR gold medal for skiing at the age of 65. He studied Mechanical Sciences at Trinity College, Cambridge, but much to his disgust his education was interrupted because of internment by the British as a suspected enemy alien. That unfortunate period (I remember him saying to me "Can you believe the stupidity, interring people like me who had fled from Nazi Germany?") had one good outcome: on his first night in camp he met Hermann Bondi who had an important influence on his early development as a scientist. They were both born in Vienna, their parents knew each other, and they were fellow students at Trinity, but this was their first meeting. On release, he went immediately into top-secret radar research for the British Admiralty, working as a team with Bondi and Fred Hoyle in a farm cottage in Dunsfold, Surrey. Tommy's first published research, which was a Nature paper with R.J. Pumphrey in 1947, was not in astronomy but physiology. He applied his engineer's understanding of positive feedback to develop and test a resonance model for how the human ear determines pitch. His conclusion that pitch discrimination occurs

  17. Naming patterns reveal cultural values: patronyms, matronyms, and the U.S. culture of honor.

    Science.gov (United States)

    Brown, Ryan P; Carvallo, Mauricio; Imura, Mikiko

    2014-02-01

    Four studies examined the hypothesis that honor norms would be associated with a pronounced use of patronyms, but not matronyms, for naming children. Study 1 shows that men who endorse honor values expressed a stronger desire to use patronyms (but not matronyms) for future children, an association that was mediated by patriarchal attitudes. Study 2 presents an indirect method for assessing state patronym and matronym levels. As expected, patronym scores were significantly higher in honor states and were associated with a wide range of variables linked previously to honor-related dynamics. Study 3a shows that following the terrorist attacks of 9/11, patronyms increased in honor states, but not in non-honor states. Likewise, priming men with a fictitious terrorist attack (Study 3b) increased the association between honor ideology and patronym preferences. Together, these studies reveal a subtle social signal that reflects the masculine values of an honor culture.

  18. Gold Nanoparticles Synthesized with a Polyphenols-Rich Extract from Cornelian Cherry (Cornus mas Fruits: Effects on Human Skin Cells

    Directory of Open Access Journals (Sweden)

    Maria Perde-Schrepler

    2016-01-01

    Full Text Available Gold nanoparticles (GNPs were obtained by green synthesis with an extract from Cornus mas fruits (GNPs-CM, characterized by several methods, and their biologic effects were evaluated on two cell lines: HaCaT, normal keratinocytes, and A431, epidermoid carcinoma. GNPs were spherical with sizes between 2 and 24 nm. Their optical spectra had a dominant plasmonic band centered at 525 nm; zeta potential distribution was narrow, centered at −19.7 mV, and the mean hydrodynamic diameter was 58 nm. GNPs were visualized in both cell types entering the cells by endocytosis. The amount of gold uptaken by the cells was dose and time dependent. The intracellular concentration of Au ions was higher in HaCaT compared to A431 cells. The toxicity of GNPs-CM was dose dependent being significant only when the highest concentrations were employed. A431 cells were less affected compared to HaCaT cells, but the difference was not statistically significant. ROS production was not significant, except in HaCaT cells at the highest concentration. The comet assay revealed no significant supplementary DNA lesions, while the secretion of inflammatory cytokines was modulated by the presence of GNPs only when the cells were additionally irradiated with UVB. These results recommend GNPs-CM for further testing and possible dermatological applications.

  19. Identification of human DNA in forensic evidence by loop-mediated isothermal amplification combined with a colorimetric gold nanoparticle hybridization probe.

    Science.gov (United States)

    Watthanapanpituck, Khanistha; Kiatpathomchai, Wansika; Chu, Eric; Panvisavas, Nathinee

    2014-11-01

    A DNA test based on loop-mediated isothermal amplification (LAMP) and colorimetric gold nanoparticle (AuNP) hybridization probe to detect the presence of human DNA in forensic evidence was developed. The LAMP primer set targeted eight regions of the human cytochrome b, and its specificity was verified against the DNA of 11 animal species, which included animals closely related to humans, such as chimpanzee and orangutan. By using the AuNP probe, sequence-specific LAMP product could be detected and the test result could be visualized through the change in color. The limit of detection was demonstrated with reproducibility to be as low as 718 fg of genomic DNA, which is equivalent to approximately 100 plasmid DNA copies containing the cytochrome b DNA target region. A simple DNA extraction method for the commonly found forensic biological samples was also devised to streamline the test process. This LAMP-AuNP human DNA test showed to be a robust, specific, and cost-effective tool for the forensic identification of human specimens without requiring sophisticated laboratory instruments.

  20. An evidence on G2/M arrest, DNA damage and caspase mediated apoptotic effect of biosynthesized gold nanoparticles on human cervical carcinoma cells (HeLa)

    Energy Technology Data Exchange (ETDEWEB)

    Jeyaraj, M. [Department of Biotechnology and Genetic Engineering, School of Biotechnology, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu (India); Arun, R. [Department of Biomedical Sciences, Bharathidasan University, Tiruchirappalli 620024 (India); Sathishkumar, G. [Department of Biotechnology and Genetic Engineering, School of Biotechnology, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu (India); MubarakAli, D. [Central Inter-Disciplinary Research Facility, Mahatma Gandhi Medical College and Research Institute Campus, Pondicherry 607402 (India); Rajesh, M.; Sivanandhan, G.; Kapildev, G.; Manickavasagam, M. [Department of Biotechnology and Genetic Engineering, School of Biotechnology, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu (India); Thajuddin, N. [Department of Microbiology, Bharathidasan University, Tiruchirappalli 620024 (India); Ganapathi, A., E-mail: aganapathi2007@gmail.com [Department of Biotechnology and Genetic Engineering, School of Biotechnology, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu (India)

    2014-04-01

    Highlights: • Gold nanoparticles (AuNPs) have been synthesized using Podophyllum hexandrum L. • AuNPs induces the oxidative stress to cell death in human cervical carcinoma cells. • It activates the caspase-cascade to cellular death. • It is actively blocks G2/M phase of cell cycle. - Abstract: Current prospect of nanobiotechnology involves in the greener synthesis of nanostructured materials particularly noble metal nanoparticles for various biomedical applications. In this study, biologically (Podophyllum hexandrum L.) synthesized crystalline gold nanoparticles (AuNPs) with the size range between 5 and 35 nm were screened for its anticancereous potential against human cervical carcinoma cells (HeLa). Stoichiometric proportion of the reaction mixture and conditions were optimized to attain stable nanoparticles with narrow size range. Different high throughput techniques like transmission electron microscope (TEM), X-ray diffraction (XRD) and UV–vis spectroscopy were adopted for the physio-chemical characterization of AuNPs. Additionally, Fourier transform infrared spectroscopy (FTIR) study revealed that the water soluble fractions present in the plant extract solely influences the reduction of AuNPs. Sublimely, synthesized AuNPs exhibits an effective in vitro anticancer activity against HeLa cells via induction of cell cycle arrest and DNA damage. Furthermore, it was evidenced that AuNPs treated cells are undergone apoptosis through the activation of caspase cascade which subsequently leads to mitochondrial dysfunction. Thereby, this study proves that biogenic colloidal AuNPs can be developed as a promising drug candidature for human cervical cancer therapy.

  1. Human serum albumin-coated gold nanoparticles for selective extraction of lysozyme from real-world samples prior to capillary electrophoresis.

    Science.gov (United States)

    Yeh, Pei-Rong; Tseng, Wei-Lung

    2012-12-14

    This study describes the use of human serum albumin (HSA)-modified gold nanoparticles (HSA-AuNPs) for the selective extraction and enrichment of high-pI protein, lysozyme (Lyz) prior to analysis by capillary electrophoresis (CE) with UV detection. HSA-AuNPs are capable of extracting Lyz from a complex matrix because a HSA capping layer not only stabilizes gold nanoparticles in a high-salt environment but also exhibits strong electrostatic attraction with Lyz under neutral pH condition. Efficient separation of Lyz and other high-pI proteins has been successfully achieved by the filling of cationic polyelectrolyte, poly(diallydimethylammonium chloride) (PDDAC), to the background electrolyte. After capturing Lyz with HSA-AuNPs, PDDAC-filled CE can be directly used for the analysis of the extracted Lyz without the addition of the releasing agent into the extractor. The extraction efficiency relied on the pH of the solution and the concentration of HSA-AuNPs. Under optimal extraction conditions, the limit of detection at a signal-to-noise ratio of 3 for Lyz was down to 8 nM. The combination of HSA-AuNP extraction and PDDAC-filled CE has been applied the analyses of Lyz in hen egg white, human milk, and human tear. Also, this NP-based extraction can be coupled to matrix-assisted desorption/ionization time-of-flight mass spectrometry and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Committed to the Honor Code: An Investment Model Analysis of Academic Integrity

    Science.gov (United States)

    Dix, Emily L.; Emery, Lydia F.; Le, Benjamin

    2014-01-01

    Educators worldwide face challenges surrounding academic integrity. The development of honor codes can promote academic integrity, but understanding how and why honor codes affect behavior is critical to their successful implementation. To date, research has not examined how students' "relationship" to an honor code predicts…

  3. Mentors, Muses, and Mutuality: Honoring Barbara Snell Dohrenwend

    Science.gov (United States)

    Mulvey, Anne

    2012-01-01

    I describe feminist community psychology principles that have the potential to expand and enrich mentoring and that honor Barbara Snell Dohrenwend, a leader who contributed to the research, theory, and profession of community psychology. I reflect on the affect that Barbara Dohrenwend had on life and on the development of feminist community…

  4. Celebrating and Honoring Teachers and the Teaching Profession

    Science.gov (United States)

    Liu, Karen

    2008-01-01

    On April 30, 2008, at the White House Rose Garden, President Bush announced that Michael Geisen, a middle school 7th-grade science teacher from Prineville, Oregon, would be the recipient of the 2008 National Teacher of the Year honor. The National Teacher of the Year is selected by a National Selection Committee, which consists of 15 major…

  5. Codes, Ciphers, and Cryptography--An Honors Colloquium

    Science.gov (United States)

    Karls, Michael A.

    2010-01-01

    At the suggestion of a colleague, I read "The Code Book", [32], by Simon Singh to get a basic introduction to the RSA encryption scheme. Inspired by Singh's book, I designed a Ball State University Honors Colloquium in Mathematics for both majors and non-majors, with material coming from "The Code Book" and many other sources. This course became…

  6. A Dual Perspective on AP, Dual Enrollment, and Honors

    Science.gov (United States)

    Camp, Heather C.; Walters, Giovanna E.

    2016-01-01

    As co-authors of this response to Annmarie Guzy's essay, these authors provide different vantage points on prior-credit programs that arise from their distinct roles on campus, and together they suggest the appropriate way forward for honors. To represent their unique perspectives and to mimic the ongoing back-and-forth on this topic on their…

  7. Exploratory Honors Students: Academic Major and Career Decision Making

    Science.gov (United States)

    Carduner, Jessie; Padak, Gary M.; Reynolds, Jamie

    2011-01-01

    In this qualitative study, we investigated the academic major and career decision-making processes of honors college students who were declared as "exploratory" students in their freshman year at a large, public, midwestern university. We used semistandardized interviews and document analysis as primary data collection methods to answer…

  8. The Honors College Experience Reconsidered: Exploring the Student Perspective

    Science.gov (United States)

    Young, James H., III; Story, Lachel; Tarver, Samantha; Weinauer, Ellen; Keeler, Julia; McQuirter, Allison

    2016-01-01

    Often administrators overlook the student voice in developing strategic plans, mission and vision statements, marketing strategies, student services, and extracurricular programming. Engaging students in these areas may enhance students' cooperation, interactions, responsibility, and expectations. In order to assess honors students' perspectives…

  9. An American Honors Program in the Arab Gulf

    Science.gov (United States)

    Yyelland, Byrad

    2012-01-01

    The first Western honors program to be established in the Arab Gulf is offered in Doha, Qatar, on a small satellite campus of an American university. Doha is the capital city of Qatar, a sovereign Arab state physically located on a small peninsula bordering Saudi Arabia in the south and jutting into the Persian Gulf. With a population of only 1.7…

  10. An Honors Interdisciplinary Community-Based Research Course

    Science.gov (United States)

    Dunbar, David; Terlecki, Melissa; Watterson, Nancy; Ratmansky, Lisa

    2013-01-01

    This article describes how two faculty members at Cabrini College--one from biology and the other from psychology--incorporated interdisciplinary community-based research in an honors course on environmental watershed issues. The course, Environmental Psychology, was team-taught in partnership with a local watershed organization, the Valley Creek…

  11. An Honors Koan: Selling Water by the River

    Science.gov (United States)

    Portnoy, Jeffrey A.

    2013-01-01

    Since Jerry Herron begins his forum essay, "Notes toward an Excellent Marxist-Elitist Honors Admissions Policy," with his anecdotal True Genealogical Confessions, Jeffery Portnoy, writes here that he feels feel obligated to begin in a similar mode. One side of Portnoy's family was in the real estate business in St. Louis, and the other…

  12. Gold in Modern Economy

    Directory of Open Access Journals (Sweden)

    Boryshkevych Olena V.

    2014-01-01

    Full Text Available The article studies the role of gold in modern economy. It analyses dynamics and modern state of the gold market. It studies volumes of contracts in exchange and off-exchange markets. In order to reveal changes of key features of the gold market, it focuses on the study of gold demand volumes, studies volumes and geographical changes in the world gold mining, and analyses volumes of monetary gold of central banks and its share in gold and currency reserves. It analyses price fluctuations in the gold market during 1968 – 2013 and identifies main factors that determine the gold price. It identifies interconnection between the state of the gold market and financial markets of countries. The study showed that namely geopolitical and economic instability restricts the spectrum of financial assets for investing and gold is not only a safe investment object but also a profitable one.

  13. AGU honors 79 geophysicists during 2011 awards cycle

    Science.gov (United States)

    Paredes, Beth

    2012-02-01

    At the 2011 Fall Meeting, AGU honored 79 esteemed geophysicists for their landmark achievements and transformational discoveries, highlighting those who have pioneered new frontiers of scientific knowledge with dedication, commitment, and leadership. Sixty individuals widely recognized as experts in their fields of research were honored as the 2011 class of AGU Fellows. These scientists, who share a lifelong commitment to understanding how the world works and are dedicated to making it a better place, were nominated by their colleagues for spurring major paradigm shifts and innovating breakthrough discoveries in Earth and space sciences. Six Union awardees received recognition for their vision and leadership, for furthering education in the Earth and space sciences, and for outstanding and sustained achievements in science journalism. In addition, AGU presented its inaugural Climate Communication Prize, for outstanding contributions to scientific literacy and public awareness about the urgent problem of climate change.

  14. Shame, honor and responsibility in clinical dialog about lifestyle issues

    DEFF Research Database (Denmark)

    Guassora, A.D.; Reventlow, S.; Malterud, K.

    2014-01-01

    OBJECTIVE: To explore how patients enact presentations of self in consultations dealing with lifestyle in general practice. METHODS: We conducted a qualitative observational study with thematic, cross-case analysis of video-recorded consultations inspired by discourse analysis. RESULTS: Patients...... presented themselves with an orientation toward responsibility in dialog about lifestyle. They described how they were taking care of themselves and doing their best. In this respect, they demonstrated their achievements as matters of honor. If one lifestyle issue was considered problematic, in some cases......: Negotiations of shame and honor, revolving around personal responsibility, are embedded in clinical discourse about lifestyle. Patients take a proactive role in presenting and defending the self against shame. PRACTICE IMPLICATIONS: GPs should pay more attention to the tacit role of shame in consultations...

  15. The Value of SAT Scores and High School Grades in the Selection of Honors Program Candidates from the Perspective of Honors Students and Graduates

    Science.gov (United States)

    Roszkowski, Michael J.; Nigro, Richard A.

    2015-01-01

    Admission to honors programs is competitive and typically relies heavily on the applicant's high school grades and SAT scores. Research shows that of the two criteria, the stronger predictor of performance in an honors curriculum is the high school record, which would imply that grades should receive the greater emphasis. We surveyed current…

  16. Mulberry leaf extract mediated synthesis of gold nanoparticles and its anti-bacterial activity against human pathogens

    International Nuclear Information System (INIS)

    Adavallan, K; Krishnakumar, N

    2014-01-01

    Gold nanoparticles (Au-NPs) were synthesized at room temperature using Morus alba (mulberry) leaf extract as reducing and stabilizing agent. The development of plant mediated synthesis of nanoparticles is gaining importance due to its simplicity, low cost, non-toxicity, eco-friendliness, long term stability and reproducible aqueous synthesis method to obtain a self-assembly of nearly monodispersed Au-NPs. The formation and morphology of biosynthesized nanoparticles are investigated with the help of UV-Vis spectroscopy, dynamic light scattering (DLS), transmission electron microscopy (TEM), atomic force microscopy (AFM), x-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) techniques. Au-NPs formation was screened by UV-Vis spectroscopy through color conversion due to surface plasmon resonance band at 538 nm for Au-NPs. DLS studies revealed that the average size of Au-NPs was 50 nm. TEM studies showed the particles to be nearly spherical with few irregular shapes and particle size ranges 15−53 nm. The AFM image clearly shows the surface morphology of the well-dispersed Au-NPs with less than 50 nm. The high crystallinity of nanoparticles is evident from bright circular spots in the selected area electron diffraction (SAED) pattern. X-ray diffraction pattern showed high purity and face-centered cubic structure of Au-NPs. The FT-IR results indicate the presence of different functional groups present in the biomolecule capping the nanoparticles. Further, biosynthesized Au-NPs show strong zone of inhibition against Vibrio cholera (gram-negative) and Staphylococcus aureus (gram-positive) whereas, chemically synthesized Au-NPs and mulberry leaf extract exhibit a fair zone of inhibition. (papers)

  17. Fully human IgG and IgM antibodies directed against the carcinoembryonic antigen (CEA Gold 4 epitope and designed for radioimmunotherapy (RIT of colorectal cancers

    Directory of Open Access Journals (Sweden)

    Pugnière Martine

    2004-10-01

    Full Text Available Abstract Background Human monoclonal antibodies (MAbs are needed for colon cancer radioimmunotherapy (RIT to allow for repeated injections. Carcinoembryonic antigen (CEA being the reference antigen for immunotargeting of these tumors, we developed human anti-CEA MAbs. Methods XenoMouse®-G2 animals were immunized with CEA. Among all the antibodies produced, two of them, VG-IgG2κ and VG-IgM, were selected for characterization in vitro in comparison with the human-mouse chimeric anti-CEA MAb X4 using flow cytometry, surface plasmon resonance, and binding to radiolabeled soluble CEA and in vivo in human colon carcinoma LS174T bearing nude mice. Results Flow cytometry analysis demonstrated binding of MAbs on CEA-expressing cells without any binding on NCA-expressing human granulocytes. In a competitive binding assay using five reference MAbs, directed against the five Gold CEA epitopes, VG-IgG2κ and VG-IgM were shown to be directed against the Gold 4 epitope. The affinities of purified VG-IgG2κ and VG-IgM were determined to be 0.19 ± 0.06 × 108 M-1 and 1.30 ± 0.06 × 108 M-1, respectively, as compared with 0.61 ± 0.05 × 108 M-1 for the reference MAb X4. In a soluble phase assay, the binding capacities of VG-IgG2κ and VG-IgM to soluble CEA were clearly lower than that of the control chimeric MAb X4. A human MAb concentration of about 10-7 M was needed to precipitate approximatively 1 ng 125I-rhCEA as compared with 10-9 M for MAb X4, suggesting a preferential binding of the human MAbs to solid phase CEA. In vivo, 24 h post-injection, 125I-VG-IgG2κ demonstrated a high tumor uptake (25.4 ± 7.3%ID/g, close to that of 131I-X4 (21.7 ± 7.2%ID/g. At 72 h post-injection, 125I-VG-IgG2κ was still concentrated in the tumor (28.4 ± 11.0%ID/g whereas the tumor concentration of 131I-X4 was significantly reduced (12.5 ± 4.8%ID/g. At no time after injection was there any accumulation of the radiolabeled MAbs in normal tissues. A pertinent analysis of

  18. Multiplexed determination of human growth hormone and prolactin at a label free electrochemical immunosensor using dual carbon nanotube-screen printed electrodes modified with gold and PEDOT nanoparticles.

    Science.gov (United States)

    Serafín, V; Martínez-García, G; Agüí, L; Yáñez-Sedeño, P; Pingarrón, J M

    2014-09-21

    A label-free dual electrochemical immunosensor was constructed for the multiplexed determination of human growth (hGH) and prolactin (PRL) hormones. The immunosensor used an electrochemical platform composed of carbon nanotube-screen printed carbon electrodes (CNT/SPCEs) modified with poly(ethylene-dioxythiophene) (PEDOT) and gold nanoparticles, on which the corresponding hGH and PRL antibodies were immobilized. The affinity reactions were monitored by measuring the decrease in the differential pulse voltammetric oxidation response of the redox probe dopamine. The experimental variables involved in the preparation of both AuNP/PEDOT/CNT/SPC modified electrodes and the dual immunosensor were optimized. The immunosensor exhibited an improved analytical performance for hGH and PRL with respect to other electrochemical immunosensor designs, showing wide ranges of linearity and low detection limits of 4.4 and 0.22 pg mL(-1), respectively. An excellent selectivity against other hormones and in the presence of ascorbic and uric acids was found. The usefulness of the dual immunosensor for the simultaneous analysis of hGH and PRL was demonstrated by analyzing human serum and saliva samples spiked with the hormones at different concentration levels.

  19. A novel reverse fluorescent immunoassay approach for sensing human chorionic gonadotropin based on silver-gold nano-alloy and magnetic nanoparticles.

    Science.gov (United States)

    Huang, Xiaopeng; Li, Yuqin; Huang, Xiang; Xie, Xiaona; Xu, Yanping; Chen, Yaowen; Gao, Wenhua

    2016-01-01

    A novel and environmentally friendly reverse fluorescent immunoassay approach was proposed and utilized for sensing human chorionic gonadotropin (HCG) in human serum by coupling a newly prepared and highly fluorescent glutathione-stabilized silver-gold nano-alloy (GSH-AgAuNAs) with magnetic nanoparticles (MNPs). To construct such a reverse system, fluorescent GSH-AgAuNAs and MNPs were first prepared and bio-functionalized with monoclonal antibodies (Mab-I and Mab-II) toward HCG antigen, respectively. Then, the GSH-AgAuNAs functionalized with Mab-I were incubated with HCG, followed by the addition of MNPs attached to Mab-II. Thereafter, a sandwich-type immunoassay could be constructed for determination of HCG owing to the antibody-antigen recognition between the functionalized GSH-AgAuNAs and MNPs. Afterwards, a magnetic collection was employed. Hence, the amount of GSH-AgAuNAs would be reduced through an immuno-magnetic separation, thus weakening the fluorescent intensity. Different from conventional immunoassay, our work determined the quantitative signal by measuring the decreasing gradient fluorescent intensity. Under optimal conditions, the developed reverse method exhibited a wide linear range of 0.5-600 ng mL(-1) toward HCG with a detection limit of 0.25 ng mL(-1). Additionally, the proposed immunoassay was validated using spiked samples, illustrating a satisfactory result in practical application.

  20. Development of a colloidal gold immunochromatographic strip assay for simple and fast detection of human α-lactalbumin in genetically modified cow milk.

    Science.gov (United States)

    Tao, Chenyu; Zhang, Qingde; Feng, Na; Shi, Deshi; Liu, Bang

    2016-03-01

    The qualitative and quantitative declaration of food ingredients is important to consumers, especially for genetically modified food as it experiences a rapid increase in sales. In this study, we designed an accurate and rapid detection system using colloidal gold immunochromatographic strip assay (GICA) methods to detect genetically modified cow milk. First, we prepared 2 monoclonal antibodies for human α-lactalbumin (α-LA) and measured their antibody titers; the one with the higher titer was used for further experiments. Then, we found the optimal pH value and protein amount of GICA for detection of pure milk samples. The developed strips successfully detected genetically modified cow milk and non-modified cow milk. To determine the sensitivity of GICA, a quantitative ELISA system was used to determine the exact amount of α-LA, and then genetically modified milk was diluted at different rates to test the sensitivity of GICA; the sensitivity was 10 μg/mL. Our results demonstrated that the applied method was effective to detect human α-LA in cow milk. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  1. Gold - Old Drug with New Potentials.

    Science.gov (United States)

    Faa, Gavino; Gerosa, Clara; Fanni, Daniela; Lachowicz, Joanna I; Nurchi, Valeria M

    2018-01-01

    Research into gold-based drugs for a range of human diseases has seen a revival in recent years. This article reviews the most important applications of gold products in different fields of human pathology. Au(I) and Au(III) compounds have been re-introduced in clinical practice for targeting the cellular components involved in the onset and progression of viral and parasitic diseases, rheumatoid arthritis and cancer. After some brief historical notes, this article takes into account the applications of gold compounds against Mycobacterium tuberculosis, and also in tuberculosis and in rheumatoid arthritis treatment. The use of gold containing drugs in the cure of cancer are then considered, with special emphasis to the use of nanoparticles and to the photo-thermal cancer therapy. The use of colloidal gold in diagnostics, introduced in the last decade is widely discussed. As a last point a survey on the adverse effects and on the toxicity of the various gold derivatives in use in medicine is presented. In this review, we described the surprisingly broad spectrum of possible uses of gold in diagnostics and in therapeutic approaches to multiple human diseases, ranging from degenerative to infectious diseases, and to cancer. In particular, gold nanoparticles appear as attractive elements in modern clinical medicine, combining high therapeutic properties, high selectivity in targeting cancer cells and low toxicity. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. Reactivity of Cys4 Zinc Finger Domains with Gold(III) Complexes : Insights into the Formation of "Gold Fingers"

    NARCIS (Netherlands)

    Jacques, Aurélie; Lebrun, Colette; Casini, Angela; Kieffer, Isabelle; Proux, Olivier; Latour, Jean-Marc; Sénèque, Olivier

    2015-01-01

    Gold(I) complexes such as auranofin or aurothiomalate have been used as therapeutic agents for the treatment of rheumatoid arthritis for several decades. Several gold(I) and gold(III) complexes have also shown in vitro anticancer properties against human cancer cell lines, including cell lines

  3. The synergistic radiosensitizing effect of tirapazamine-conjugated gold nanoparticles on human hepatoma HepG2 cells under X-ray irradiation

    Directory of Open Access Journals (Sweden)

    Liu X

    2016-07-01

    Full Text Available Xi Liu,1–4 Yan Liu,1–4 Pengcheng Zhang,1–4 Xiaodong Jin,1–3 Xiaogang Zheng,1–4 Fei Ye,1–4 Weiqiang Chen,1–3 Qiang Li1–3 1Institute of Modern Physics, 2Key Laboratory of Heavy Ion Radiation Biology and Medicine, Chinese Academy of Sciences, 3Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou, 4School of Life Science, University of Chinese Academy of Sciences, Beijing, People’s Republic of China Abstract: Reductive drug-functionalized gold nanoparticles (AuNPs have been proposed to enhance the damage of X-rays to cells through improving hydroxyl radical production by secondary electrons. In this work, polyethylene glycol-capped AuNPs were conjugated with tirapazamine (TPZ moiety, and then thioctyl TPZ (TPZs-modified AuNPs (TPZs-AuNPs were synthesized. The TPZs-AuNPs were characterized by transmission electron microscopy, ultraviolet-visible spectra, dynamic light scattering, and inductively coupled plasma mass spectrometry to have a size of 16.6±2.1 nm in diameter and a TPZs/AuNPs ratio of ~700:1. In contrast with PEGylated AuNPs, the as-synthesized TPZs-AuNPs exhibited 20% increment in hydroxyl radical production in water at 2.0 Gy, and 19% increase in sensitizer enhancement ratio at 10% survival fraction for human hepatoma HepG2 cells under X-ray irradiation. The production of reactive oxygen species in HepG2 cells exposed to X-rays in vitro demonstrated a synergistic radiosensitizing effect of AuNPs and TPZ moiety. Thus, the reductive drug-conjugated TPZs-AuNPs as a kind of AuNP radiosensitizer with low gold loading provide a new strategy for enhancing the efficacy of radiation therapy. Keywords: AuNPs, radiation enhancement, synergistic effect, human hepatoma cells, hydroxyl radical production

  4. Human exposure to mercury in artisanal small-scale gold mining areas of Kedougou region, Senegal, as a function of occupational activity and fish consumption.

    Science.gov (United States)

    Niane, Birane; Guédron, Stéphane; Moritz, Robert; Cosio, Claudia; Ngom, Papa Malick; Deverajan, Naresh; Pfeifer, Hans Rudolf; Poté, John

    2015-05-01

    We investigated mercury (Hg) exposure of food web and humans in the region of Kedougou, Senegal, where Hg is used for gold amalgamation in artisanal small-scale gold mining (ASGM). For this purpose, total mercury (THg) concentration was determined in eight fish species and two shellfish species from Gambia River and in human hair from 111 volunteers of different age and sex, living in urban locations (Kedougou and Samekouta) or in ASGM areas (Tinkoto and Bantako). THg concentrations in fish samples range from 0.03 to 0.51 mg kg(-1) wet weight (ww) and 0.5 to 1.05 mg kg(-1) ww for shellfish. THg concentrations in fish are below the WHO guideline of 0.5 mg kg(-1) ww, whereas 100 % of shellfish are above this safety guideline. In the entire set of fish and shellfish samples, we documented a decrease of THg concentrations with increasing selenium to mercury (Se:Hg) ratio suggesting a protection of Se against Hg. However, local population consuming fish from the Gambia River in the two ASGM areas have higher THg concentrations (median = 1.45 and 1.5 mg kg(-1) at Bantako and Tinkoto) in hair than those from others localities (median = 0.42 and 0.32 mg kg(-1) at Kedougou town and Samekouta) who have diverse diets. At ASGM sites, about 30 % of the local population present Hg concentrations in hair exceeding 1 mg kg(-1), defined as the reference concentration of Hg in hair. We also evidence a higher exposure of women to Hg in the Tinkoto ASGM site due to the traditional distribution of daily tasks where women are more involved in the burning of amalgams. The discrepancy between the calculated moderate exposure through fish consumption and the high Hg concentrations measured in hair suggest that fish consumption is not the only source of Hg exposure and that further studies should focus on direct exposure to elemental Hg of population living at ASGM sites.

  5. Gold-Mining

    DEFF Research Database (Denmark)

    Raaballe, J.; Grundy, B.D.

    2002-01-01

    of operating gold mines. Asymmetric information on the reserves in the mine implies that, at a high enough price of gold, the manager of high type finds the extraction value of the company to be higher than the current market value of the non-operating gold mine. Due to this under valuation the maxim of market...... value maximization forces the manager of high type to extract the gold.The implications are three-fold. First, all managers (except the lowest type) extract the gold too soon compared to the first-best policy of leaving the gold in the mine forever. Second, a manager of high type extracts the gold......  Based on standard option pricing arguments and assumptions (including no convenience yield and sustainable property rights), we will not observe operating gold mines. We find that asymmetric information on the reserves in the gold mine is a necessary and sufficient condition for the existence...

  6. Gold Standard Testing of Motion Based Tracking Systems

    Science.gov (United States)

    2017-03-15

    AFRL-RH-WP-TR-2017-0032 GOLD STANDARD TESTING OF MOTION BASED TRACKING SYSTEMS Joshua Hagen Human Signatures Branch Human-Centered ISR Division...DD-MM-YY) 2. REPORT TYPE 3. DATES COVERED (From - To) 15 03 17 Interim Report June 2016 – March 2017 4. TITLE AND SUBTITLE Gold Standard Testing of...systems against a ‘ Gold Standard ’ on-field measurement system for human physiological performance monitoring. Data shows that the accuracy of the

  7. High-Impact Recruiting: A Focus Group of Prospective Honors Students

    Science.gov (United States)

    Rhea, David M.; Goodwin, Kristy

    2014-01-01

    In 2013-2014, the Governors State University (GSU) Honors Program was faced with a need to evolve from a two-year honors program serving juniors and seniors only to a four-year honors program. This need was born out of the university's transition to a four-year university in 2014-2015. This mandate led to some concerns that the author, the newly…

  8. The human combinatorial antibody library HuCAL GOLD combines diversification of all six CDRs according to the natural immune system with a novel display method for efficient selection of high-affinity antibodies.

    Science.gov (United States)

    Rothe, Christine; Urlinger, Stefanie; Löhning, Corinna; Prassler, Josef; Stark, Yvonne; Jäger, Ute; Hubner, Bernd; Bardroff, Michael; Pradel, Ingrid; Boss, Melanie; Bittlingmaier, Renate; Bataa, Tschimegma; Frisch, Christian; Brocks, Bodo; Honegger, Annemarie; Urban, Margit

    2008-02-29

    This article describes the generation of the Human Combinatorial Antibody Library HuCAL GOLD. HuCAL GOLD is a synthetic human Fab library based on the HuCAL concept with all six complementarity-determining regions (CDRs) diversified according to the sequence and length variability of naturally rearranged human antibodies. The human antibody repertoire was analyzed in-depth, and individual CDR libraries were designed and generated for each CDR and each antibody family. Trinucleotide mixtures were used to synthesize the CDR libraries in order to ensure a high quality within HuCAL GOLD, and a beta-lactamase selection system was employed to eliminate frame-shifted clones after successive cloning of the CDR libraries. With these methods, a large, high-quality library with more than 10 billion functional Fab fragments was achieved. By using CysDisplay, the antibody fragments are displayed on the tip of the phage via a disulfide bridge between the phage coat protein pIII and the heavy chain of the antibody fragment. Efficient elution of specific phages is possible by adding reducing agents. HuCAL GOLD was challenged with a variety of different antigens and proved to be a reliable source of high-affinity human antibodies with best affinities in the picomolar range, thus functioning as an excellent source of antibodies for research, diagnostic, and therapeutic applications. Furthermore, the data presented in this article demonstrate that CysDisplay is a robust and broadly applicable display technology even for high-throughput applications.

  9. A perspective on the history of health and human rights: from the Cold War to the Gold War.

    Science.gov (United States)

    Tarantola, Daniel

    2008-04-01

    Through the end of the Cold War, public health policies were predominantly shaped and implemented by governments and these same governments committed themselves to meet their obligations for health under international and national laws. The post-Cold War era has witnessed the entry of new actors in public health and the sharing of power and influences with non-state actors, in particular the private sector and interest groups. This article examines the emergence of human rights and the rise of health on the international development agenda as the Cold War was ending. It highlights the convergence of health and human rights in academic and public discourse since the end of the Cold War in a context of political and economic shifts linked to the ongoing economic globalization. It describes opportunities and challenges for greater synergy between health and rights and proposes a role for health practitioners.

  10. Hard x-ray micro-tomography of a human head post-mortem as a gold standard to compare x-ray modalities

    Science.gov (United States)

    Dalstra, M.; Schulz, G.; Dagassan-Berndt, D.; Verna, C.; Müller-Gerbl, M.; Müller, B.

    2016-10-01

    An entire human head obtained at autopsy was micro-CT scanned in a nano/micro-CT scanner in a 6-hour long session. Despite the size of the head, it could still be scanned with a pixel size of 70 μm. The aim of this study was to obtain an optimal quality 3D data-set to be used as baseline control in a larger study comparing the image quality of various cone beam CT systems currently used in dentistry. The image quality of the micro-CT scans was indeed better than the ones of the clinical imaging modalities, both with regard to noise and streak artifacts due to metal dental implants. Bony features in the jaws, like the trabecular architecture and the thin wall of the alveolar bone were clearly visible. Therefore, the 3D micro-CT data-set can be used as the gold standard for linear, angular, and volumetric measurements of anatomical features in and around the oral cavity when comparing clinical imaging modalities.

  11. Labeling Human Mesenchymal Stem Cells with Gold Nanocages for in vitro and in vivo Tracking by Two-Photon Microscopy and Photoacoustic Microscopy

    Science.gov (United States)

    Zhang, Yu Shrike; Wang, Yu; Wang, Lidai; Wang, Yucai; Cai, Xin; Zhang, Chi; Wang, Lihong V.; Xia, Younan

    2013-01-01

    Stem cell tracking is a highly important subject. Current techniques based on nanoparticle-labeling, such as magnetic resonance imaging, fluorescence microscopy, and micro-computed tomography, are plagued by limitations including relatively low sensitivity or penetration depth, involvement of ionizing irradiation, and potential cytotoxicity of the nanoparticles. Here we introduce a new class of contrast agents based on gold nanocages (AuNCs) with hollow interiors and porous walls to label human mesenchymal stem cells (hMSCs) for both in vitro and in vivo tracking using two-photon microscopy and photoacoustic microscopy. As demonstrated by the viability assay, the AuNCs showed negligible cytotoxicity under a reasonable dose, and did not alter the differentiation potential of the hMSCs into desired lineages. We were able to image the cells labeled with AuNCs in vitro for at least 28 days in culture, as well as to track the cells that homed to the tumor region in nude mice in vivo. PMID:23946820

  12. Hard x-ray micro-tomography of a human head post-mortem as a gold standard to compare X-ray modalities

    DEFF Research Database (Denmark)

    Dalstra, Michel; Schulz, Georg; Dagassan-Berndt, Dorothea

    2016-01-01

    in a larger study comparing the image quality of various cone beam CT systems currently used in dentistry. The image quality of the micro-CT scans was indeed better than the ones of the clinical imaging modalities, both with regard to noise and streak artifacts due to metal dental implants. Bony features......An entire human head obtained at autopsy was micro-CT scanned in a nano/micro-CT scanner in a 6-hour long session. Despite the size of the head, it could still be scanned with a pixel size of 70 μm. The aim of this study was to obtain an optimal quality 3D data-set to be used as baseline control...... in the jaws, like the trabecular architecture and the thin wall of the alveolar bone were clearly visible. Therefore, the 3D micro-CT data-set can be used as the gold standard for linear, angular, and volumetric measurements of anatomical features in and around the oral cavity when comparing clinical imaging...

  13. Photocatalytic Inactivation Effect of Gold-Doped TiO2 (Au/TiO2 Nanocomposites on Human Colon Carcinoma LoVo Cells

    Directory of Open Access Journals (Sweden)

    Zhiyu Jiang

    2007-11-01

    Full Text Available The photocatalytic inactivation effecting of gold-doped TiO2 (Au/TiO2 nanocomposites on human colon carcinoma LoVo cells was investigated for the first time. The Au/TiO2 samples containing different amounts of Au (1–4 wt% were prepared by deposition-precipitation (DP method. These synthesized Au/TiO2 nanocomposites were characterized by transmission electron microscopy (TEM and inductively coupled plasma atomic emission spectroscopy. It was found that the photocatalytic inactivation effect of TiO2 nanoparticles on LoVo cancer cells could be greatly improved by the surface modification of Au nanoparticles. Furthermore, the loading amount of Au on the surface of TiO2 nanoparticles affects the photocatalytic inactivation efficiency strongly, and it was found that the most efficient nanocomposites were TiO2 nanoparticles doped with 2 wt% Au. When 50 μg/mL 2 wt% Au/TiO2 nanocomposites were used, all of the LoVo cancer cells were killed under the irradiation of UV light (λmax = 365 nm, Intensity = 1.8 mW/cm2 within 100 minutes. But for 50 μg/mL TiO2 nanoparticles, only 40% cancer cells were killed under the same condition.

  14. Size- and time-dependent alteration in metabolic activities of human hepatic cytochrome P450 isozymes by gold nanoparticles via microsomal coincubations

    Science.gov (United States)

    Ye, Meiling; Tang, Ling; Luo, Mengjun; Zhou, Jing; Guo, Bin; Liu, Yangyuan; Chen, Bo

    2014-11-01

    Nano-sized particles are known to interfere with drug-metabolizing cytochrome P450 (CYP) enzymes, which can be anticipated to be a potential source of unintended adverse reactions, but the mechanisms underlying the inhibition are still not well understood. Herein we report a systematic investigation of the impacts of gold nanoparticles (AuNPs) on five major CYP isozymes under in vitro incubations of human liver microsomes (HLMs) with tannic acid (TA)-stabilized AuNPs in the size range of 5 to 100 nm. It is found that smaller AuNPs show more pronounced inhibitory effects on CYP2C9, CYP2C19, CYP2D6, and CYP3A4 in a dose-dependent manner, while 1A2 is the least susceptible to the AuNP inhibition. The size- and dose-dependent CYP-specific inhibition and the nonspecific drug-nanogold binding in the coincubation media can be significantly reduced by increasing the concentration ratio of microsomal proteins to AuNPs, probably via a noncompetitive mode. Remarkably, AuNPs are also found to exhibit a slow time-dependent inactivation of 2D6 and 3A4 in a β-nicotinamide adenine dinucleotide 2'-phosphate reduced tetrasodium salt hydrate (NADPH)-independent manner. During microsomal incubations, UV-vis spectroscopy, dynamic light scattering, and zeta-potential measurements were used to monitor the changes in particle properties under the miscellaneous AuNP/HLM/CYP dispersion system. An improved stability of AuNPs by mixing HLM with the gold nanocolloid reveals that the stabilization via AuNP-HLM interactions may occur on a faster time scale than the salt-induced nanoaggregation by incubation in phosphate buffer. The results suggest that the AuNP induced CYP inhibition can be partially attributed to its adhesion onto the enzymes to alter their structural conformations or onto the HLM membrane therefore impairing the integral membrane proteins. Additionally, AuNPs likely block the substrate pocket on the CYP surface, depending on both the particle characteristics and the

  15. Mercury Levels in Human Hair and Farmed Fish near Artisanal and Small-Scale Gold Mining Communities in the Madre de Dios River Basin, Peru

    Directory of Open Access Journals (Sweden)

    Aubrey L. Langeland

    2017-03-01

    Full Text Available Artisanal and small-scale gold mining (ASGM has been an important source of income for communities in the Madre de Dios River Basin in Peru for hundreds of years. However, in recent decades, the scale of ASGM activities in the region has increased dramatically, and exposures to a variety of occupational and environmental hazards related to ASGM, including mercury, are becoming more widespread. The aims of our study were to: (1 examine patterns in the total hair mercury level of human participants in several communities in the region and compare these results to the 2.2 µg/g total hair mercury level equivalent to the World Health Organization (WHO Expert Committee of Food Additives (JECFA’s Provisional Tolerable Weekly Intake (PTWI; and (2, to measure the mercury levels of paco (Piaractus brachypomus fish raised in local aquaculture ponds, in order to compare these levels to the EPA Fish Tissue Residue Criterion of 0.3 µg Hg/g fish (wet weight. We collected hair samples from 80 participants in four communities (one control and three where ASGM activities occurred in the region, and collected 111 samples from fish raised in 24 local aquaculture farms. We then analyzed the samples for total mercury. Total mercury levels in hair were statistically significantly higher in the mining communities than in the control community, and increased with increasing geodesic distance from the Madre de Dios headwaters, did not differ by sex, and frequently exceeded the reference level. Regression analyses indicated that higher hair mercury levels were associated with residence in ASGM communities. The analysis of paco fish samples found no samples that exceeded the EPA tissue residue criterion. Collectively, these results align with other recent studies showing that ASGM activities are associated with elevated human mercury exposure. The fish farmed through the relatively new process of aquaculture in ASGM areas appeared to have little potential to contribute

  16. Mercury Levels in Human Hair and Farmed Fish near Artisanal and Small-Scale Gold Mining Communities in the Madre de Dios River Basin, Peru.

    Science.gov (United States)

    Langeland, Aubrey L; Hardin, Rebecca D; Neitzel, Richard L

    2017-03-14

    Artisanal and small-scale gold mining (ASGM) has been an important source of income for communities in the Madre de Dios River Basin in Peru for hundreds of years. However, in recent decades, the scale of ASGM activities in the region has increased dramatically, and exposures to a variety of occupational and environmental hazards related to ASGM, including mercury, are becoming more widespread. The aims of our study were to: (1) examine patterns in the total hair mercury level of human participants in several communities in the region and compare these results to the 2.2 µg/g total hair mercury level equivalent to the World Health Organization (WHO) Expert Committee of Food Additives (JECFA)'s Provisional Tolerable Weekly Intake (PTWI); and (2), to measure the mercury levels of paco ( Piaractus brachypomus ) fish raised in local aquaculture ponds, in order to compare these levels to the EPA Fish Tissue Residue Criterion of 0.3 µg Hg/g fish (wet weight). We collected hair samples from 80 participants in four communities (one control and three where ASGM activities occurred) in the region, and collected 111 samples from fish raised in 24 local aquaculture farms. We then analyzed the samples for total mercury. Total mercury levels in hair were statistically significantly higher in the mining communities than in the control community, and increased with increasing geodesic distance from the Madre de Dios headwaters, did not differ by sex, and frequently exceeded the reference level. Regression analyses indicated that higher hair mercury levels were associated with residence in ASGM communities. The analysis of paco fish samples found no samples that exceeded the EPA tissue residue criterion. Collectively, these results align with other recent studies showing that ASGM activities are associated with elevated human mercury exposure. The fish farmed through the relatively new process of aquaculture in ASGM areas appeared to have little potential to contribute to human

  17. Adsorption of human insulin on single-crystal gold surfaces investigated by in situ scanning tunnelling microscopy and electrochemistry

    DEFF Research Database (Denmark)

    Welinder, Anna Christina; Zhang, Jingdong; Steensgaard, D.B.

    2010-01-01

    We have explored the adsorption of zinc-free human insulin on the three low-index single-crystalline Au(111)-, Au(100)- and Au(110)-surfaces in aqueous buffer (KH2PO4, pH 5) by a combination of electrochemical scanning tunnelling microscopy (in situ STM) at single-molecule resolution and linear...... sweep, LSV, cyclic, CV, and square wave (SQWV) voltammetry. Multifarious electrochemical patterns were observed. Most attention was given to reductive desorption caused by insulin binding to the Au-surfaces via up to three disulfide groups per insulin monomer, presumably converted to single Au-S links...

  18. Analysis of self-directed mastery learning of honors physics

    Science.gov (United States)

    Athens, Wendy

    Self-directed learning (SDL) is an important life skill in a knowledge-based society and prepares students to persist, manage their time and resources, use logic to construct their knowledge, argue their views, and collaborate. The purpose of this study was to facilitate mastery of physics concepts through self-directedness in formative testing with feedback, a choice of learning activities, and multiple forms of support. This study was conducted within two sections of honors physics at a private high school (N=24). Students' learning activity choices, time investments, and perceptions (assessed through a post survey) were tracked and analyzed. SDL readiness was linked to success in mastering physics concepts. The three research questions pursued in this study were: What SDL activities did honors physics students choose in their self-directed mastery learning environment? How many students achieved concept mastery and how did they spend their time? Did successful and unsuccessful students perceive the self-directed mastery learning environment differently? Only seven of 24 students were successful in passing the similar concept-based unit tests within four tries, and these seven students were separated into a "successful" group and the other 17 into an "unsuccessful" group. Differences between the two groups were analyzed. A profile of a self-directed secondary honors physics student emerged. A successful self-directed student invested more time learning from activities rather than simply completing them, focused on learning concepts more than rote operations, intentionally selected activities to fill in gaps of knowledge and practice concepts, actively constructed knowledge into a cognitive framework, engaged in academic discourse with instructor and peers as they made repeated attempts to master content and pass the test given constructive feedback, used a wide variety of learning resources, and managed their workload to meet deadlines. This capstone study found

  19. Developing Trustworthy Commissioned Officers: Transcending the Honor Codes and Concept

    Science.gov (United States)

    2012-10-01

    Kurt   Lewin ,  Albert  Bandura,  Edgar   Schein  and  other...most   schools’   honor   codes  prohibit.     Similarly,  Dr.   James  Rest’s   four   stage   model  of  moral...of  the  Federal  Service  Academies  to  maintain  tradition   and   the   “way   things  were,”   change   is  

  20. Essays on the future in honor of Nick Metropolis

    CERN Document Server

    Rota, Gian-Carlo

    2000-01-01

    This collection represents a unique undertaking in scientific publishing to honor Nick Metropolis. Nick was the last survivor of the World War II Manhattan Project in Los Alamos, and was an important member of the Los Alamos national Laboratory until his death in October, 1999. In this volume, some of the leading scientists and humanists of our time have contributed essays related to their respective disciplines, exploring various aspects of future developments in science and society, philosophy, national security, nuclear power, pure and applied mathematics, physics and biology, particle physics, computing, and information science.

  1. Surface chemistry of gold nanoparticles determines the biocorona composition impacting cellular uptake, toxicity and gene expression profiles in human endothelial cells.

    Science.gov (United States)

    Chandran, Parwathy; Riviere, Jim E; Monteiro-Riviere, Nancy A

    2017-05-01

    This study investigated the role of nanoparticle size and surface chemistry on biocorona composition and its effect on uptake, toxicity and cellular responses in human umbilical vein endothelial cells (HUVEC), employing 40 and 80 nm gold nanoparticles (AuNP) with branched polyethyleneimine (BPEI), lipoic acid (LA) and polyethylene glycol (PEG) coatings. Proteomic analysis identified 59 hard corona proteins among the various AuNP, revealing largely surface chemistry-dependent signature adsorbomes exhibiting human serum albumin (HSA) abundance. Size distribution analysis revealed the relative instability and aggregation inducing potential of bare and corona-bound BPEI-AuNP, over LA- and PEG-AuNP. Circular dichroism analysis showed surface chemistry-dependent conformational changes of proteins binding to AuNP. Time-dependent uptake of bare, plasma corona (PC) and HSA corona-bound AuNP (HSA-AuNP) showed significant reduction in uptake with PC formation. Cell viability studies demonstrated dose-dependent toxicity of BPEI-AuNP. Transcriptional profiling studies revealed 126 genes, from 13 biological pathways, to be differentially regulated by 40 nm bare and PC-bound BPEI-AuNP (PC-BPEI-AuNP). Furthermore, PC formation relieved the toxicity of cationic BPEI-AuNP by modulating expression of genes involved in DNA damage and repair, heat shock response, mitochondrial energy metabolism, oxidative stress and antioxidant response, and ER stress and unfolded protein response cascades, which were aberrantly expressed in bare BPEI-AuNP-treated cells. NP surface chemistry is shown to play the dominant role over size in determining the biocorona composition, which in turn modulates cell uptake, and biological responses, consequently defining the potential safety and efficacy of nanoformulations.

  2. Antiviral Activity of Gold/Copper Sulfide Core/Shell Nanoparticles against Human Norovirus Virus-Like Particles.

    Directory of Open Access Journals (Sweden)

    Jessica Jenkins Broglie

    Full Text Available Human norovirus is a leading cause of acute gastroenteritis worldwide in a plethora of residential and commercial settings, including restaurants, schools, and hospitals. Methods for easily detecting the virus and for treating and preventing infection are critical to stopping norovirus outbreaks, and inactivation via nanoparticles (NPs is a more universal and attractive alternative to other physical and chemical approaches. Using norovirus GI.1 (Norwalk virus-like particles (VLPs as a model viral system, this study characterized the antiviral activity of Au/CuS core/shell nanoparticles (NPs against GI.1 VLPs for the rapid inactivation of HuNoV. Inactivation of VLPs (GI.1 by Au/CuS NPs evaluated using an absorbance-based ELISA indicated that treatment with 0.083 μM NPs for 10 min inactivated ~50% VLPs in a 0.37 μg/ml VLP solution and 0.83 μM NPs for 10 min completely inactivated the VLPs. Increasing nanoparticle concentration and/or VLP-NP contact time significantly increased the virucidal efficacy of Au/CuS NPs. Changes to the VLP particle morphology, size, and capsid protein were characterized using dynamic light scattering, transmission electron microscopy, and Western blot analysis. The strategy reported here provides the first reported proof-of-concept Au/CuS NPs-based virucide for rapidly inactivating human norovirus.

  3. The action of NIR (808nm) laser radiation and gold nanorods labeled with IgA and IgG human antibodies on methicillin-resistant and methicillin sensitive strains of Staphylococcus aureus

    Science.gov (United States)

    Tuchina, Elena S.; Petrov, Pavel O.; Ratto, Fulvio; Centi, Sonia; Pini, Roberto; Tuchin, Valery V.

    2015-03-01

    The effect of NIR laser radiation (808 nm) on methicillin-sensitive and methicillin resistant strains of Staphylococcus aureus incubated with gold nanorods is studied. Nanorods having length of 44 (± 4) nm and diameter of 10 (± 3) nm with the absorption maximum in the NIR (800 nm), functionalized with human immunoglobulins IgA and IgG, were synthesized and used in the studies. The killing ability up to 97% of the microorganism populations by using this nanotechnology was shown.

  4. Skin contact with gold and gold alloys.

    Science.gov (United States)

    Rapson, W S

    1985-08-01

    3 types of reaction to gold merit discussion. First, there is the effect known as black dermographism, in which stroking with certain metals immediately produces well-defined black lines on the skin. Some gold alloys are amongst such metals. The evidence indicates that the effect is the result of impregnation of the skin with black metallic particles generated by mechanical abrasion of the metal by contaminants of the skin. There is no positive and unequivocal evidence of the ability of metals to mark uncontaminated skin so rapidly that it is possible to write upon it. Secondly there are the 2 related phenomena of the wear of gold jewelry, and the susceptibility to certain individuals to blackening of the skin where it is in contact with such jewelry. The occurrence of smudge, as it is often called, is not very common, but is brought to the attention of most jewelers from time to time. In extreme cases it may make it embarrassing for the person concerned to wear metallic jewelry. It would appear as if gold smudge also results mainly from mechanical abrasion of jewelry, though this may be aided and/or supplemented in some instances by corrosion of gold or gold alloy induced by certain components of the sweat. Finally, there is the question of true allergic responses to contact of the skin with gold and its alloys. Judging from the very few cases which have been recorded, such responses are extremely rare. Some recent observations on the reactions of metallic gold with amino acids and of reaction to contact of the skin with gold on the part of rheumatoid arthritis patients undergoing gold therapy, are, however, relevant in this connection.

  5. Gold in plants

    International Nuclear Information System (INIS)

    Girling, C.A.; Peterson, P.J.

    1980-01-01

    Many plants have the ability to take up gold from the soil and to accumulate it in their tisssue. Advances have been made in understanding these processes to the point where their exploitation in the field of prospecting for gold appears practically feasible. Neutron activation analysis is used for the determination of the small quantities of gold in plants

  6. Validation of a microsphere immunoassay for serological leptospirosis diagnosis in human serum by comparison to the current gold standard.

    Directory of Open Access Journals (Sweden)

    Sarah J Wynwood

    2015-03-01

    Full Text Available A microsphere immunoassay (MIA utilising Luminex xMap technology that is capable of determining leptospirosis IgG and IgM independently was developed. The MIA was validated using 200 human samples submitted for routine leptospirosis serology testing. The traditional microscopic agglutination (MAT method (now 100 years old suffers from a significant range of technical problems including a dependence on antisera which is difficult to source and produce, false positive reactions due to auto-agglutination and an inability to differentiate between IgG and IgM antibodies. A comparative validation method of the MIA against the MAT was performed and used to determine the ability of the MIA to detect leptospiral antibodies when compared with the MAT. The assay was able to determine samples in the reactive, equivocal and non-reactive ranges when compared to the MAT and was able to differentiate leptospiral IgG antibodies from leptospiral IgM antibodies. The MIA is more sensitive than the MAT and in true infections was able to detect low levels of antibody in the later stages of the acute phase as well as detect higher levels of IgM antibody earlier in the immune phase of the infection. The relatively low cost, high throughput platform and significantly reduced dependency on large volumes of rabbit antisera make this assay worthy of consideration for any microbiological assay that currently uses agglutination assays.

  7. Jesus the Healer: A Sermon in Honor of the Memory of Donald Eric Capps (1939-2015).

    Science.gov (United States)

    Ferrell, Donald R

    2018-04-01

    The article below is a sermon preached in 2008. It was inspired by Donald Capps's book, Jesus the Village Psychiatrist. I offer this sermon in honor of his memory as a creative contributor to the work of the Journal as well as his distinguished career as Professor of Pastoral Theology at Princeton Theological Seminary. Many of us have been blessed by his profound psychological and theological insights into the human psyche, his scholarly explorations of the relationship of psychology and religion, and his remarkable sense of humor. We are diminished by his absence.

  8. Honoring Avicenna, the great Persian physician on the world's postage stamps.

    Science.gov (United States)

    Afshar, Ahmadreza

    2010-09-01

    Many nations are indebted to Avicenna (Ibn-Sina) for their scientific progressions and civilization. Many countries in the Middle East, Africa, and Europe have honored Avicenna, the great Persian scientist, by depicting his vignette on their postage stamps. The symbolic value of Avicenna has been chosen to commemorate scientific occasions, achievements and anniversaries, which represents the ultimate performance of conscious honoring.

  9. Grounding cultural syndromes : Body comportment and values in honor and dignity cultures

    NARCIS (Netherlands)

    Ijzerman, H.; Cohen, D.

    2011-01-01

    The body is a carrier of relatively complex cultural values. Three experiments examined links between body comportment and honor (a cultural syndrome prizing female chastity, familial loyalty, and reputation). We put participants from nonhonor (Anglo-Americans; Experiment 1) and honor (Latinos;

  10. The Cultural Encounters Model: Incorporating Campus Events into the Honors Curriculum

    Science.gov (United States)

    Pfrehm, James; Sullivan, Robert

    2013-01-01

    Honors students are, almost by definition, committed to excellence. As a result, they tend to be overextended (Guzy). They also "tend to be more eager, exploratory, and experienced than their non-honors counterparts" (Achterberg 77). They typically take a full load of coursework while at the same time juggling clubs, learning…

  11. The Unique Role of Two-Year Honors Colleges and Programs

    Science.gov (United States)

    Armstrong, J. David, Jr.

    2015-01-01

    As President of Broward College, the author is proud of the honors education that has been offered to students since 1982. Two-year colleges play a crucial role in higher education, having experienced extensive growth in the past few decades and with honors as an important part of that growth. Broward College was founded in 1960 to support the…

  12. Histochemical evidence for the differential surface labeling, uptake, and intracellular transport of a colloidal gold-labeled insulin complex by normal human blood cells

    International Nuclear Information System (INIS)

    Ackerman, G.A.; Wolken, K.W.

    1981-01-01

    A colloidal gold-labeled insulin-bovine serum albumin (GIA) reagent has been developed for the ultrastructural visualization of insulin binding sites on the cell surface and for tracing the pathway of intracellular insulin translocation. When applied to normal human blood cells, it was demonstrated by both visual inspection and quantitative analysis that the extent of surface labeling, as well as the rate and degree of internalization of the insulin complex, was directly related to cell type. Further, the pathway of insulin (GIA) transport via round vesicles and by tubulo-vesicles and saccules and its subsequent fate in the hemic cells was also related to cell variety. Monocytes followed by neutrophils bound the greatest amount of labeled insulin. The majority of lymphocytes bound and internalized little GIA, however, between 5-10% of the lymphocytes were found to bind considerable quantities of GIA. Erythrocytes rarely bound the labeled insulin complex, while platelets were noted to sequester large quantities of the GIA within their extracellular canalicular system. GIA uptake by the various types of leukocytic cells appeared to occur primarily by micropinocytosis and by the direct opening of cytoplasmic tubulo-vesicles and saccules onto the cell surface in regions directly underlying surface-bound GIA. Control procedures, viz., competitive inhibition of GIA labeling using an excess of unlabeled insulin in the incubation medium, preincubation of the GIA reagent with an antibody directed toward porcine insulin, and the incorporation of 125I-insulin into the GIA reagent, indicated the specificity and selectivity of the GIA histochemical procedure for the localization of insulin binding sites

  13. Therapeutic effects of gold nanoparticles synthesized using Musa paradisiaca peel extract against multiple antibiotic resistant Enterococcus faecalis biofilms and human lung cancer cells (A549).

    Science.gov (United States)

    Vijayakumar, S; Vaseeharan, B; Malaikozhundan, B; Gopi, N; Ekambaram, P; Pachaiappan, R; Velusamy, P; Murugan, K; Benelli, G; Suresh Kumar, R; Suriyanarayanamoorthy, M

    2017-01-01

    Botanical-mediated synthesis of nanomaterials is currently emerging as a cheap and eco-friendly nanotechnology, since it does not involve the use of toxic chemicals. In the present study, we focused on the synthesis of gold nanoparticles using the aqueous peel extract of Musa paradisiaca (MPPE-AuNPs) following a facile and cheap fabrication process. The green synthesized MPPE-AuNPs were bio-physically characterized by UV-Vis spectroscopy, FTIR, XRD, TEM, Zeta potential analysis and EDX. MPPE-AuNPs were crystalline in nature, spherical to triangular in shape, with particle size ranging within 50 nm. The biofilm inhibition activity of MPPE-AuNPs was higher against multiple antibiotic resistant (MARS) Gram-positive Enterococcus faecalis. Light and confocal laser scanning microscopic observations evidenced that the MPPE-AuNPs effectively inhibited the biofilm of E. faecalis when tested at 100 μg mL -1 . Cytotoxicity studies demonstrated that MPPE-AuNPs were effective in inhibiting the viability of human A549 lung cancer cells at higher concentrations of 100 μg mL -1 . The morphological changes in the MPPE-AuNPs treated A549 lung cancer cells were visualized under phase-contrast microscopy. Furthermore, the ecotoxicity of MPPE-AuNPs on the freshwater micro crustacean Ceriodaphnia cornuta were evaluated. Notably, no mortality was recorded in MPPE-AuNPs treated C. cornuta at 250 μg mL -1 . This study concludes that MPPE-AuNPs are non-toxic, eco-friendly and act as a multipurpose potential biomaterial for biomedical applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Computer simulations of the interaction of human immunodeficiency virus (HIV) aspartic protease with spherical gold nanoparticles: implications in acquired immunodeficiency syndrome (AIDS)

    Science.gov (United States)

    Whiteley, Chris G.; Lee, Duu-Jong

    2016-09-01

    The interaction of gold nanoparticles (AuNP) with human immune-deficiency virus aspartic protease (HIVPR) is modelled using a regime of molecular dynamics simulations. The simulations of the ‘docking’, first as a rigid-body complex, and eventually through flexible-fit analysis, creates 36 different complexes from four initial orientations of the nanoparticle strategically positioned around the surface of the enzyme. The structural deviations of the enzymes from the initial x-ray crystal structure during each docking simulation are assessed by comparative analysis of secondary structural elements, root mean square deviations, B-factors, interactive bonding energies, dihedral angles, radius of gyration (R g), circular dichroism (CD), volume occupied by C α , electrostatic potentials, solvation energies and hydrophobicities. Normalisation of the data narrows the selection from the initial 36 to one ‘final’ probable structure. It is concluded that, after computer simulations on each of the 36 initial complexes incorporating the 12 different biophysical techniques, the top five complexes are the same no matter which technique is explored. The significance of the present work is an expansion of an earlier study on the molecular dynamic simulation for the interaction of HIVPR with silver nanoparticles. This work is supported by experimental evidence since the initial ‘orientation’ of the AgNP with the enzyme is the same as the ‘final’ AuNP-HIVPR complex generated in the present study. The findings will provide insight into the forces of the binding of the HIVPR to AuNP. It is anticipated that the protocol developed in this study will act as a standard process for the interaction of any nanoparticle with any biomedical target.

  15. Combination of UV-vis spectroscopy and chemometrics to understand protein-nanomaterial conjugate: a case study on human serum albumin and gold nanoparticles.

    Science.gov (United States)

    Wang, Yong; Ni, Yongnian

    2014-02-01

    Study of the interactions between proteins and nanomaterials is of great importance for understanding of protein nanoconjugate. In this work, we choose human serum albumin (HSA) and citrate-capped gold nanoparticles (AuNPs) as a model of protein and nanomaterial, and combine UV-vis spectroscopy with multivariate curve resolution by an alternating least squares (MCR-ALS) algorithm to present a new and efficient method for comparatively comprehensive study of evolution of protein nanoconjugate. UV-vis spectroscopy coupled with MCR-ALS allows qualitative and quantitative extraction of the distribution diagrams, spectra and kinetic profiles of absorbing pure species (AuNPs and AuNPs-HSA conjugate are herein identified) and undetectable species (HSA) from spectral data. The response profiles recovered are converted into the desired thermodynamic, kinetic and structural parameters describing the protein nanoconjugate evolution. Analysis of these parameters for the system gives evidence that HSA molecules are very likely to be attached to AuNPs surface predominantly as a flat monolayer to form a stable AuNPs-HSA conjugate with a core-shell structure, and the binding process takes place mainly through electrostatic and hydrogen-bond interactions between the positively amino acid residues of HSA and the negatively carboxyl group of citrate on AuNPs surface. The results obtained are verified by transmission electron microscopy, zeta potential, circular dichroism spectroscopy and Fourier transform infrared spectroscopy, showing the potential of UV-vis spectroscopy for study of evolution of protein nanoconjugate. In parallel, concentration evolutions of pure species resolved by MCR-ALS are used to construct a sensitive spectroscopic biosensor for HSA with a linear range from 1.8 nM to 28.1 nM and a detection limit of 0.8 nM. © 2013 Published by Elsevier B.V.

  16. Nitrogen-doped multiple graphene aerogel/gold nanostar as the electrochemical sensing platform for ultrasensitive detection of circulating free DNA in human serum.

    Science.gov (United States)

    Ruiyi, Li; Ling, Liu; Hongxia, Bei; Zaijun, Li

    2016-05-15

    Graphene aerogel has attracted increasing attention due to its large specific surface area, high-conductivity and electronic interaction. The paper reported a facile synthesis of nitrogen-doped multiple graphene aerogel/gold nanostar (termed as N-doped MGA/GNS) and its use as the electrochemical sensing platform for detection of double stranded (dsDNA). On the one hand, the N-doped MGA offers a much better electrochemical performance compared with classical graphene aerogel. Interestingly, the performance can be enhanced by only increasing the cycle number of graphene oxide gelation. On the other hand, the hybridization with GNS further enhances the electrocatalytic activity towards Fe(CN)6(3-/4-). In addition, the N-doped MGA/GNS provides a well-defined three-dimensional architecture. The unique structure make it is easy to combine with dsDNA to form the electroactive bioconjugate. The integration not only triggers an ultrafast DNA electron and charge transfer, but also realizes a significant synergy between N-doped MGA, GNS and dsDNA. As a result, the electrochemical sensor based on the hybrid exhibits highly sensitive differential pulse voltammetric response (DPV) towards dsDNA. The DPV signal linearly increases with the increase of dsDNA concentration in the range from 1.0×10(-)(21) g ml(-)(1) to 1.0×10(-16) g ml(-1) with the detection limit of 3.9×10(-22) g ml(-1) (S/N=3). The sensitivity is much more than that of all reported DNA sensors. The analytical method was successfully applied in the electrochemical detection of circulating free DNA in human serum. The study also opens a window on the electrical properties of multiple graphene aerogel and DNA as well their hybrids to meet the needs of further applications as special nanoelectronics in molecule diagnosis, bioanalysis and catalysis. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Ground Optical Lightning Detector (GOLD)

    Science.gov (United States)

    Jackson, John, Jr.; Simmons, David

    A photometer developed to characterize lightning from the ground is discussed. The detector and the electronic signal processing and data storage systems are presented along with field data measured by the system. The discussion will include improvements that will be incorporated to enhance the measurement of lightning and the data storage capability to record for many days without human involvement. Finally, the calibration of the GOLD system is presented.

  18. The Pursuit of Excellence: An Analysis of the Honors College Application and Enrollment Decision for a Large Public University

    Science.gov (United States)

    Singell, Larry D., Jr.; Tang, Hui-Hsuan

    2012-01-01

    Honors colleges housed in public universities began only in the last half century, but have become nearly ubiquitous over the last 20 years. This paper, using recent data from the oldest stand-alone honors college in the country, is the first to study how the application and enrollment decisions of honors college students differ from the general…

  19. Hierarchical decision modeling essays in honor of Dundar F. Kocaoglu

    CERN Document Server

    2016-01-01

    This volume, developed in honor of Dr. Dundar F. Kocaoglu, aims to demonstrate the applications of the Hierarchical Decision Model (HDM) in different sectors and its capacity in decision analysis. It is comprised of essays from noted scholars, academics and researchers of engineering and technology management around the world. This book is organized into four parts: Technology Assessment, Strategic Planning, National Technology Planning and Decision Making Tools. Dr. Dundar F. Kocaoglu is one of the pioneers of multiple decision models using hierarchies, and creator of the HDM in decision analysis. HDM is a mission-oriented method for evaluation and/or selection among alternatives. A wide range of alternatives can be considered, including but not limited to, different technologies, projects, markets, jobs, products, cities to live in, houses to buy, apartments to rent, and schools to attend. Dr. Kocaoglu’s approach has been adopted for decision problems in many industrial sectors, including electronics rese...

  20. Monoclonal antibody "gold rush".

    Science.gov (United States)

    Maggon, Krishan

    2007-01-01

    The market, sales and regulatory approval of new human medicines, during the past few years, indicates increasing number and share of new biologics and emergence of new multibillion dollar molecules. The global sale of monoclonal antibodies in 2006 were $20.6 billion. Remicade had annual sales gain of $1 billion during the past 3 years and five brands had similar increase in 2006. Rituxan with 2006 sales of $4.7 billion was the best selling monoclonal antibody and biological product and the 6th among the top selling medicinal brand. It may be the first biologic and monoclonal antibody to reach $10 billion annual sales in the near future. The strong demand from cancer and arthritis patients has surpassed almost all commercial market research reports and sales forecast. Seven monoclonal antibody brands in 2006 had sales exceeding $1 billion. Humanized or fully human monoclonal antibodies with low immunogenicity, enhanced antigen binding and reduced cellular toxicity provide better clinical efficacy. The higher technical and clinical success rate, overcoming of technical hurdles in large scale manufacturing, low cost of market entry and IND filing, use of fully human and humanized monoclonal antibodies has attracted funds and resources towards R&D. Review of industry research pipeline and sales data during the past 3 years indicate a real paradigm shift in industrial R&D from pharmaceutical to biologics and monoclonal antibodies. The antibody bandwagon has been joined by 200 companies with hundreds of new projects and targets and has attracted billions of dollars in R&D investment, acquisitions and licensing deals leading to the current Monoclonal Antibody Gold Rush.

  1. Gold mineralogy and extraction

    Energy Technology Data Exchange (ETDEWEB)

    Cashion, J.D.; Brown, L.J. [Monash University, Physics Department (Australia)

    1998-12-15

    Several examples are examined in which Moessbauer spectroscopic analysis of gold mineral samples, treated concentrates and extracted species has provided information not obtainable by competing techniques. Descriptions are given of current work on bacterial oxidation of pyritic ores and on the adsorbed species from gold extracted from cyanide and chloride solutions onto activated carbon and polyurethane foams. The potential benefits for the gold mining industry from Moessbauer studies and some limitations on the use of the technique are also discussed.

  2. Gold and uranium extraction

    International Nuclear Information System (INIS)

    James, G.S.; Davidson, R.J.

    1977-01-01

    A process for extracting gold and uranium from an ore containing them both comprising the steps of pulping the finely comminuted ore with a suitable cyanide solution at an alkaline pH, acidifying the pulp for uranium dissolution, adding carbon activated for gold recovery to the pulp at a suitable stage, separating the loaded activated carbon from the pulp, and recovering gold from the activated carbon and uranium from solution

  3. Magnetism in nanocrystalline gold.

    Science.gov (United States)

    Tuboltsev, Vladimir; Savin, Alexander; Pirojenko, Alexandre; Räisänen, Jyrki

    2013-08-27

    While bulk gold is well known to be diamagnetic, there is a growing body of convincing experimental and theoretical work indicating that nanostructured gold can be imparted with unconventional magnetic properties. Bridging the current gap in experimental study of magnetism in bare gold nanomaterials, we report here on magnetism in gold nanocrystalline films produced by cluster deposition in the aggregate form that can be considered as a crossover state between a nanocluster and a continuous film. We demonstrate ferromagnetic-like hysteretic magnetization with temperature dependence indicative of spin-glass-like behavior and find this to be consistent with theoretical predictions, available in the literature, based on first-principles calculations.

  4. Life history, code of honor, and emotional responses to inequality in an economic game.

    Science.gov (United States)

    Pedersen, Eric J; Forster, Daniel E; McCullough, Michael E

    2014-10-01

    The code of honor, which is characterized by a preoccupation with reputation and willingness to take retaliatory action, has been used extensively to explain individual and cultural differences in peoples' tendencies to behave aggressively. However, research on the relationship between the code of honor and emotional responses to social interactions has been limited in scope, focusing primarily on anger in response to insults and reputational threats. Here we broaden this scope by examining the relationship between code of honor and emotional reactions in response to an unfair economic exchange that resulted in unequal monetary earnings among 3 laboratory participants. We found that endorsement of the code of honor was related to anger and envy in response to unfair monetary distributions. Interestingly, code of honor predicted envy above and beyond what could be accounted for by anger, but the converse was not the case. This suggests that the code of honor influenced perceptions of how subjects viewed their own earnings relative to those of others, which consequently was responsible for their apparent anger as a result of the economic transaction. Furthermore, the unique relationship between code of honor and envy was present only for subjects who received unfair treatment and not for subjects who merely witnessed unfair treatment. Additionally, we replicated previous findings that harsh childhood environmental conditions are associated with endorsement of the code of honor, highlighting the potential value of incorporating a life history theoretical approach to investigating individual differences in endorsement of the code of honor. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  5. Complementary mass spectrometric techniques for the quantification of the protein corona: a case study on gold nanoparticles and human serum proteins

    Science.gov (United States)

    Fernández-Iglesias, Nerea; Bettmer, Jörg

    2015-08-01

    Once nanoparticles enter a biological system, it is known that their surface is instantly covered by the biomolecules present with preference to proteins. This protein corona has been a subject of numerous studies in order to reveal its composition. Besides that, growing interest exists in its quantitative determination in order to gain a deeper insight into the nature of these nanoparticle-protein bioconjugates. Only a few analytical methods are available nowadays, so the aim of this study is to provide a reliable and alternative methodology for the quantification of the protein corona. The suggested approach is based on the assumption that the total protein content within the corona can be correlated to its sulfur concentration due to the presence of cysteine and methionine as sulfur-containing amino acids. Once the most abundant proteins had been identified with the use of gel electrophoresis with subsequent peptide analysis by electrospray ionization-tandem mass spectrometry (ESI-MS/MS), the isolated nanoparticle-protein conjugates were subjected to total analysis of sulfur and the corresponding metal being present in the nanoparticles by inductively coupled plasma-mass spectrometry (ICP-MS). The concept is exemplarily demonstrated on citrate-stabilized gold nanoparticles (GNPs) incubated with human serum. Two different purification procedures were tested in order to isolate the sought bioconjugates. 26 most abundant proteins could be identified and an average of approximately 40 S atoms per protein was calculated and used for further studies. ICP-MS analyses of S/Au ratios served for the quantification of the protein corona revealing an absolute number of proteins bound to the incubated GNPs. Two main results could be obtained for this specific system under the chosen experimental conditions: the number of proteins per GNP decreased with their size from 10 nm to 60 nm and the obtained values suggested that the protein corona in this specific case was

  6. Understanding Employment Discrimination Law: Clarifying Disparate Treatment Analysis after St. Mary's Honor Center V. Hicks

    National Research Council Canada - National Science Library

    Miller, Thomas D

    1994-01-01

    In St. Mary's Honor Center v Hicks, a bitterly divided Supreme Court clashed over the extent and nature of the plaintiff's final burden of persuasion under the McDonnell Douglas Corporation v Green...

  7. 12 New England Organizations Honored for Outstanding Achievements in Energy Efficiency

    Science.gov (United States)

    EPA and the U.S. Department of Energy (DOE) are honoring 12 New England businesses and organizations for their commitment to saving energy, saving money, and protecting the environment through superior energy efficiency achievements.

  8. Honoring the Call to Duty: Veterans’ Disability Benefits in the 21st Century

    Science.gov (United States)

    2007-10-01

    Steve Buyer , Ranking Republican Member, Committee on Veterans’ Affairs, U. S. House of Representatives Honorable Ike Skelton, Chairman...phobic, obsessive- compulsive , and depressive reactions; and dropped outmoded diagnoses, such as neurasthenia and involutional psychoses.21 In 1971, VA

  9. Masculine and family honor and youth violence: The moderating role of ethnic-cultural affiliation.

    Science.gov (United States)

    Khoury-Kassabri, Mona

    2016-01-01

    This study examines the involvement in violent behavior of at-risk Arab and Jewish male youth from a large city in Israel. It explores the role masculine and family honor plays in predicting youth involvement in violence and tests whether this association is moderated by ethnic-cultural affiliation. A total of 282 males (59.2% Arab), aged 15-21, filled out a self-report closed-ended questionnaire. We found that among both Jewish and Arab youth a greater concern with masculine honor was positively associated with involvement in violence. We also found that Arab youth are significantly more involved in violent behavior than Jewish youth, and that Arab participants were more concerned with masculine and family honor. However, contrary to what was expected, greater concern with family honor was associated with lower levels of Arab youth involvement in violence. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  10. Statement of Honorable Donald C. Winter Secretary of the Navy Before the House Armed Services Committee

    National Research Council Canada - National Science Library

    Winter, Donald C

    2007-01-01

    Mr. Chairman, Mr. Ranking Member, and Members of the Committee, it is an honor to appear before you representing the brave men and women of the United States Navy and the United States Marine Corps active, reserve...

  11. For Distinguished Public Service: Medical Library Association Honors FNLM and NIH MedlinePlus Magazine | NIH ...

    Science.gov (United States)

    ... Medical Library Association Honors FNLM and NIH MedlinePlus Magazine Past Issues / Summer 2011 Table of Contents MLA ... From You We want your feedback on the magazine and ideas for future issues, as well as ...

  12. Male honor and female fidelity: implicit cultural scripts that perpetuate domestic violence.

    Science.gov (United States)

    Vandello, Joseph A; Cohen, Dov

    2003-05-01

    Two studies explored how domestic violence may be implicitly or explicitly sanctioned and reinforced in cultures where honor is a salient organizing theme. Three general predictions were supported: (a) female infidelity damages a man's reputation, particularly in honor cultures; (b) this reputation can be partially restored through the use of violence; and (c) women in honor cultures are expected to remain loyal in the face of jealousy-related violence. Study 1 involved participants from Brazil (an honor culture) and the United States responding to written vignettes involving infidelity and violence in response to infidelity. Study 2 involved southern Anglo, Latino, and northern Anglo participants witnessing a "live" incident of aggression against a woman (actually a confederate) and subsequently interacting with her.

  13. Information Technology Strategies for Honor Society and Organization Membership Retention in Online Nursing Programs.

    Science.gov (United States)

    Hopkins, Emily E; Wasco, Jennifer J

    Membership retention in an honor society or organization is of utmost importance for sustainability. However, retaining members in organizations that serve online education nursing students can be a challenging task. Understanding the importance of creating a sense of community to promote retention within an honor society chapter, nursing faculty at a small private university implemented different online approaches. This article highlights successful information technology strategies to promote membership retention in organizations for online nursing students.

  14. Silver, gold, and alloyed silver–gold nanoparticles: characterization and comparative cell-biologic action

    International Nuclear Information System (INIS)

    Mahl, Dirk; Diendorf, Jörg; Ristig, Simon; Greulich, Christina; Li Zian; Farle, Michael; Köller, Manfred; Epple, Matthias

    2012-01-01

    Silver, gold, and silver–gold-alloy nanoparticles were prepared by citrate reduction modified by the addition of tannin during the synthesis, leading to a reduction in particle size by a factor of three. Nanoparticles can be prepared by this easy water-based synthesis and subsequently functionalized by the addition of either tris(3-sulfonatophenyl)phosphine or poly(N-vinylpyrrolidone). The resulting nanoparticles of silver (diameter 15–25 nm), gold (5–6 nm), and silver–gold (50:50; 10–12 nm) were easily dispersable in water and also in cell culture media (RPMI + 10 % fetal calf serum), as shown by nanoparticle tracking analysis and differential centrifugal sedimentation. High-resolution transmission electron microscopy showed a polycrystalline nature of all nanoparticles. EDX on single silver–gold nanoparticles indicated that the concentration of gold is higher inside a nanoparticle. The biologic action of the nanoparticles toward human mesenchymal stem cells (hMSC) was different: Silver nanoparticles showed a significant concentration-dependent influence on the viability of hMSC. Gold nanoparticles showed only a small effect on the viability of hMSC after 7 days. Surprisingly, silver–gold nanoparticles had no significant influence on the viability of hMSC despite the silver content. Silver nanoparticles and silver–gold nanoparticles in the concentration range of 5–20 μg mL −1 induced the activation of hMSC as indicated by the release of IL-8. In contrast, gold nanoparticles led to a reduction of the release of IL-6 and IL-8.

  15. Silver, gold, and alloyed silver-gold nanoparticles: characterization and comparative cell-biologic action

    Energy Technology Data Exchange (ETDEWEB)

    Mahl, Dirk; Diendorf, Joerg; Ristig, Simon [University of Duisburg-Essen, Department of Inorganic Chemistry, Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany); Greulich, Christina [Ruhr-University of Bochum, Bergmannsheil University Hospital/Surgical Research (Germany); Li Zian; Farle, Michael [University of Duisburg-Essen, Faculty of Physics, Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany); Koeller, Manfred [Ruhr-University of Bochum, Bergmannsheil University Hospital/Surgical Research (Germany); Epple, Matthias, E-mail: matthias.epple@uni-due.de [University of Duisburg-Essen, Department of Inorganic Chemistry, Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany)

    2012-10-15

    Silver, gold, and silver-gold-alloy nanoparticles were prepared by citrate reduction modified by the addition of tannin during the synthesis, leading to a reduction in particle size by a factor of three. Nanoparticles can be prepared by this easy water-based synthesis and subsequently functionalized by the addition of either tris(3-sulfonatophenyl)phosphine or poly(N-vinylpyrrolidone). The resulting nanoparticles of silver (diameter 15-25 nm), gold (5-6 nm), and silver-gold (50:50; 10-12 nm) were easily dispersable in water and also in cell culture media (RPMI + 10 % fetal calf serum), as shown by nanoparticle tracking analysis and differential centrifugal sedimentation. High-resolution transmission electron microscopy showed a polycrystalline nature of all nanoparticles. EDX on single silver-gold nanoparticles indicated that the concentration of gold is higher inside a nanoparticle. The biologic action of the nanoparticles toward human mesenchymal stem cells (hMSC) was different: Silver nanoparticles showed a significant concentration-dependent influence on the viability of hMSC. Gold nanoparticles showed only a small effect on the viability of hMSC after 7 days. Surprisingly, silver-gold nanoparticles had no significant influence on the viability of hMSC despite the silver content. Silver nanoparticles and silver-gold nanoparticles in the concentration range of 5-20 {mu}g mL{sup -1} induced the activation of hMSC as indicated by the release of IL-8. In contrast, gold nanoparticles led to a reduction of the release of IL-6 and IL-8.

  16. 8th Symposium Honoring Mathematical Physicist Jean-Pierre Vigier

    CERN Document Server

    Kauffman, Louis H; Rowlands, Peter; The Physics of Reality : Space, Time, Matter, Cosmos

    2013-01-01

    A truly Galilean class volume as it also introduces a new method in theory formation this time completing the tools of epistemology. This book covers a broad spectrum of theoretical and mathematical physics by researchers from over 20 nations from four continents. Like Vigier himself, the Vigier symposia are noted for addressing avant-garde cutting-edge topics in contemporary physics. Among the six proceedings honoring J-P Vigier this is perhaps the most exciting one as several important breakthroughs are introduced for the first time. The most interesting breakthrough in view of the recent NIST experimental violations of QED is a continuation of pioneering work by Vigier on Tight Bound States in Hydrogen. The new experimental protocol described not only promises empirical proof of large-scale extra dimensions in conjunction with avenues for testing string theory but also implies the birth of the field of Unified Field Mechanics ushering in a new age of discovery. Work on quantum computing redefines the qubit...

  17. Nursing Care at the Time of Death: A Bathing and Honoring Practice.

    Science.gov (United States)

    Rodgers, Debra; Calmes, Beth; Grotts, Jonathan

    2016-05-01

    To explore family members' experience of a bathing and honoring practice after a loved one's death in the acute care setting.
. A descriptive, qualitative design using a semistructured telephone interview script.
. The Inpatient Adult Oncology Unit at Santa Barbara Cottage Hospital in California. 
. 13 family members who participated in the bathing and honoring practice after their loved one's death on the oncology unit.
. Participants were selected by purposive sampling and interviewed by telephone three to six months after their loved one's death. Interviews using a semistructured script with open-ended questions were recorded, transcribed, verified, and analyzed using phenomenologic research techniques to identify common themes of experience.
. 24 first-level themes and 11 superordinate themes emerged from the data. All participants indicated that the bathing and honoring practice was a positive experience and supported the grieving process. The majority found the practice to be meaningful and stated that it honored their loved one. Many expressed that the bathing and honoring was spiritually significant in a nondenominational way and that they hope it will be made available to all families of patients who die in the hospital. 
. After patient death, a bathing and honoring practice with family member participation is positive and meaningful, and it supports family members' initial grieving.
. This study is a first step toward establishing specific nursing interventions as evidence-based practice that can be incorporated in routine nursing care for patients and families at the end of life.

  18. Medicinal gold compounds

    International Nuclear Information System (INIS)

    Parish, R.V.; Cottrill, S.M.

    1987-01-01

    A major use of gold compounds in the pharmaceutical industry is for anti-arthritic agents. The disease itself is not understood and little is known about the way in which the drugs act, but detailed pictures of the distribution of gold in the body are available, and some of the relevant biochemistry is beginning to emerge. The purpose of this article is to give a survey of the types of compounds presently employed in medicine, of the distribution of gold in the body which results from their use, and of some relevant chemistry. Emphasis is placed on results obtained in the last few years

  19. Axially chiral allenyl gold complexes.

    Science.gov (United States)

    Johnson, Alice; Laguna, Antonio; Gimeno, M Concepción

    2014-09-17

    Unprecedented allenyl gold complexes have been achieved starting from triphenylpropargylphosphonium bromide. Two different coordination modes of the allene isomer of triphenylphosphoniumpropargylide to gold have been found depending on the gold oxidation state. Bromo-, pentafluorophenyl-, and triphenylphosphine-gold(I) allenyl complexes were prepared in which the α carbon coordinates to the gold(I) center. A chiral pentafluorophenyl-gold(III) allenyl complex with the gold atoms coordinated to the γ carbon was also prepared. All the complexes have been structurally characterized by X-ray diffraction showing the characteristic distances for a C═C═C unit.

  20. Cytotoxicity and Apoptosis Inducing Activities of 2-Amino-4H-chromene-3-carbonitrile Derivatives Loaded on Gold Nanoparticles Against Human Breast Cancer Cell Line T47D.

    Science.gov (United States)

    Saffari, Zahra; Zarabi, Maryam Farahnak; Aryapour, Hasan; Foroumadi, Alireza; Farhangi, Ali; Ghassemi, Soheil; Akbarzadeh, Azim

    2015-04-01

    Chemotherapy drugs, used for prevention of uncontrolled cell proliferation in certain tissues as well as inducing apoptosis in tumor cells, are important candidates for treatment of cancer. The synthesized 2-amino-4H-chromene-3-carbonitrile derivatives effective on cancerous cells resistant to other drugs such as Paclitaxel were used due to their ability in induction of apoptosis. The growth inhibitory and inducing apoptosis activities were determined. In order to make it target-oriented, the best compound was conjugated with gold nanoparticles (NPs) by aspartic acid with chemical reduction method. Cytotoxicity effect of 2-amino-4H-chromene-3-carbonitrile derivatives against the T47D breast cancer cell line was determined by MTT assay. The synthesis of gold NPs was confirmed by transmission electron microscopy, UV-Vis and dynamic light scattering. To assess the effects of compounds on the process of apoptosis, staining methods with acridine orange-ethidium bromide and Hoechst staining by fluorescence microscopy and DNA fragmentation by the diphenylamine method were used. The synthesized compounds containing two NH2 groups on benzene rings, demonstrated more cytotoxicity effect. The effect of conjugation with gold NPs and the induction of apoptosis were studied with the best compound. The cytotoxicity effects of the synthesized 2-amino-4H-chromene-3-carbonitrile compounds were changed by replacement of NO2 group on thiol ring with different chemical groups on the benzene ring. Analyses of treated cell lines by conjugated and non-conjugated forms of compounds verified their ability in inducing apoptosis while conjugated form demonstrated higher apoptosis.

  1. Gold nanoprobes for theranostics

    Science.gov (United States)

    Panchapakesan, Balaji; Book-Newell, Brittany; Sethu, Palaniappan; Rao, Madhusudhana; Irudayaraj, Joseph

    2011-01-01

    Gold nanoprobes have become attractive diagnostic and therapeutic agents in medicine and life sciences research owing to their reproducible synthesis with atomic level precision, unique physical and chemical properties, versatility of their morphologies, flexibility in functionalization, ease of targeting, efficiency in drug delivery and opportunities for multimodal therapy. This review highlights some of the recent advances and the potential for gold nanoprobes in theranostics. PMID:22122586

  2. The Gold Standard Programme

    DEFF Research Database (Denmark)

    Neumann, Tim; Rasmussen, Mette; Ghith, Nermin

    2013-01-01

    To evaluate the real-life effect of an evidence-based Gold Standard Programme (GSP) for smoking cessation interventions in disadvantaged patients and to identify modifiable factors that consistently produce the highest abstinence rates.......To evaluate the real-life effect of an evidence-based Gold Standard Programme (GSP) for smoking cessation interventions in disadvantaged patients and to identify modifiable factors that consistently produce the highest abstinence rates....

  3. Framing Honors Physical Geology around Critical Thinking and Communication Exercises

    Science.gov (United States)

    Nunn, J. A.

    2008-12-01

    The honors section of freshman geology at LSU has 20-35 highly motivated students with ACT scores above 30. They are usually non-majors and have had no exposure to geosciences in high school. Teaching geology in Louisiana is challenging because there are virtually no rocks exposed at the surface and students with creationist beliefs are common. In addition to exams, this course requires a series of projects: plate reconstruction, minerals in the home, a metaphor for geologic time, volcano research paper, group project on volcanoes, water resources, and a comparison essay on Hurricane Katrina and the 1927 flood of the Mississippi river. The purpose of the projects is to promote critical thinking and communication skills as well as allow students to explore in greater depth topics relevant to their every day lives such as hurricanes. Critical thinking skills emphasized are interrelated processes and systems, variable temporal/spatial scales, and analysis of controversial topics such as the age of the Earth. This course is certified by LSU's Communication across the Curriculum (CxC) program as communication intensive in written and visual communication. CxC certification requires that 40% of grading depend on communication activities. Written communication exercises focus on organization, audience, incorporation and coordination of visual elements, and proper citation of sources. Visual communication exercises include working with maps, charts and graphs, and a group project where they create a poster and/or stand alone slide presentation on volcanoes geared to a middle school audience. Topics such as origin and quality of tap water, how much copper ore is used to build their home, and local geoharzards such as the Baton Rouge Fault generate a higher interest level and higher retention of information. Preliminary assessment is positive including improved exam results, higher student evaluations, recruitment of geology majors, and anecdotal evidence of long term

  4. The ultrastructural labelling of keratin proteins in normal human colonic mucosa by a low temperature embedding, protein A-gold technique.

    Science.gov (United States)

    Warhol, M J; Roth, J

    1985-07-01

    A low temperature embedding technique using protein A-gold as a marker was used to define the distribution of keratin proteins at the ultrastructural level in normal colonic epithelial cells. In both goblet and absorptive cells, keratin proteins were found at the base and lateral borders of the cell and inserting into desmosomes. There was a network of keratin filaments which surrounded cell organelles. In goblet cells, bundles of keratin filaments surrounded mucin droplets. In absorptive cells, a fine network of keratin filaments interdigitated with the terminal web. These studies with an immunochemical technique defined the keratin cytoskeleton at the ultrastructural level.

  5. Infrared light-absorbing gold/gold sulfide nanoparticles induce cell death in esophageal adenocarcinoma

    Science.gov (United States)

    Li, Yan; Gobin, Andre M; Dryden, Gerald W; Kang, Xinqin; Xiao, Deyi; Li, Su Ping; Zhang, Guandong; Martin, Robert CG

    2013-01-01

    Gold nanoparticles and near infrared-absorbing light are each innocuous to tissue but when combined can destroy malignant tissue while leaving healthy tissue unharmed. This study investigated the feasibility of photothermal ablation therapy for esophageal adenocarcinoma using chitosan-coated gold/gold sulfide (CS-GGS) nanoparticles. A rat esophagoduodenal anastomosis model was used for the in vivo ablation study, and three human esophageal cell lines were used to study the response of cancer cells and benign cells to near infrared light after treatment with CS-GGS. The results indicate that both cancerous tissue and cancer cells took up more gold nanoparticles and were completely ablated after exposure to near infrared light. The benign tissue and noncancerous cells showed less uptake of these nanoparticles, and remained viable after exposure to near infrared light. CS-GGS nanoparticles could provide an optimal endoluminal therapeutic option for near infrared light ablation of esophageal cancer. PMID:23818775

  6. Biosynthesis of gold nanoparticles using diatoms-silica-gold and EPS-gold bionanocomposite formation

    OpenAIRE

    Schröfel, Adam; Kratošová, Gabriela; Bohunická, Markéta; Dobročka, Edmund; Vávra, Ivo

    2011-01-01

    Novel synthesis of gold nanoparticles, EPS-gold, and silica-gold bionanocomposites by biologically driven processes employing two diatom strains (Navicula atomus, Diadesmis gallica) is described. Transmission electron microscopy (TEM) and electron diffraction analysis (SAED) revealed a presence of gold nanoparticles in the experimental solutions of the diatom culture mixed with tetrachloroaureate. Nature of the gold nanoparticles was confirmed by X-ray diffraction studies. Scanning electron m...

  7. Computational simulations of frictional losses in pipe networks confirmed in experimental apparatusses designed by honors students

    Science.gov (United States)

    Pohlman, Nicholas A.; Hynes, Eric; Kutz, April

    2015-11-01

    Lectures in introductory fluid mechanics at NIU are a combination of students with standard enrollment and students seeking honors credit for an enriching experience. Most honors students dread the additional homework problems or an extra paper assigned by the instructor. During the past three years, honors students of my class have instead collaborated to design wet-lab experiments for their peers to predict variable volume flow rates of open reservoirs driven by gravity. Rather than learn extra, the honors students learn the Bernoulli head-loss equation earlier to design appropriate systems for an experimental wet lab. Prior designs incorporated minor loss features such as sudden contraction or multiple unions and valves. The honors students from Spring 2015 expanded the repertoire of available options by developing large scale set-ups with multiple pipe networks that could be combined together to test the flexibility of the student team's computational programs. The engagement of bridging the theory with practice was appreciated by all of the students such that multiple teams were able to predict performance within 4% accuracy. The challenges, schedules, and cost estimates of incorporating the experimental lab into an introductory fluid mechanics course will be reported.

  8. GOLD NANOPARTICLES: A REVIVAL IN PRECIOUS METAL ADMINISTRATION TO PATIENTS

    Science.gov (United States)

    Thakor, AS; Jokerst, J; Zaveleta, C; Massoud, TF; Gambhir, SS

    2011-01-01

    Gold has been used as a therapeutic agent to treat a wide variety of rheumatic diseases including psoriatic arthritis, juvenile arthritis and discoid lupus erythematosus. Although the use of gold has been largely superseded by newer drugs, gold nanoparticles are being used effectively in laboratory based clinical diagnostic methods whilst concurrently showing great promise in vivo either as a diagnostic imaging agent or a therapeutic agent. For these reasons, gold nanoparticles are therefore well placed to enter mainstream clinical practice in the near future. Hence, the present review summarizes the chemistry, pharmacokinetics, bio-distribution, metabolism and toxicity of bulk gold in humans based on decades of clinical observation and experiments in which gold was used to treat patients with rheumatoid arthritis. The beneficial attributes of gold nanoparticles, such as their ease of synthesis, functionalization and shape control are also highlighted demonstrating why gold nanoparticles are an attractive target for further development and optimization. The importance of controlling the size and shape of gold nanoparticles to minimize any potential toxic side effects is also discussed. PMID:21846107

  9. In Vitro Quantified Determination of β-Amyloid 42 Peptides, a Biomarker of Neuro-Degenerative Disorders, in PBS and Human Serum Using a Simple, Cost-Effective Thin Gold Film Biosensor.

    Science.gov (United States)

    Dai, Yifan; Molazemhosseini, Alireza; Liu, Chung Chiun

    2017-07-20

    A simple in vitro biosensor for the detection of β-amyloid 42 in phosphate-buffered saline (PBS) and undiluted human serum was fabricated and tested based on our platform sensor technology. The bio-recognition mechanism of this biosensor was based on the effect of the interaction between antibody and antigen of β-amyloid 42 to the redox couple probe of K₄Fe(CN)₆ and K₃Fe(CN)₆. Differential pulse voltammetry (DPV) served as the transduction mechanism measuring the current output derived from the redox coupling reaction. The biosensor was a three-electrode electrochemical system, and the working and counter electrodes were 50 nm thin gold film deposited by a sputtering technique. The reference electrode was a thick-film printed Ag/AgCl electrode. Laser ablation technique was used to define the size and structure of the biosensor. Cost-effective roll-to-roll manufacturing process was employed in the fabrication of the biosensor, making it simple and relatively inexpensive. Self-assembled monolayers (SAM) of 3-Mercaptopropionic acid (MPA) was employed to covalently immobilize the thiol group on the gold working electrode. A carbodiimide conjugation approach using N -(3-dimethylaminopropyl)- N '-ethylcarbodiimide hydrochloride (EDC) and N -hydroxysuccinimide (NHS) was undertaken for cross-linking antibody of β-amyloid 42 to the carboxylic groups on one end of the MPA. The antibody concentration of β-amyloid 42 used was 18.75 µg/mL. The concentration range of β-amyloid 42 in this study was from 0.0675 µg/mL to 0.5 µg/mL for both PBS and undiluted human serum. DPV measurements showed excellent response in this antigen concentration range. Interference study of this biosensor was carried out in the presence of Tau protein antigen. Excellent specificity of this β-amyloid 42 biosensor was demonstrated without interference from other species, such as T-tau protein.

  10. Attitudes of Turkish Academics Regarding Violence Against Women in the Name of Honor.

    Science.gov (United States)

    Yeşilçiçek Çalik, Kıymet

    2017-11-01

    Honor is an important concept that has a vital value in Turkey and affects many women's lives and even causes death. It is of utmost importance to know and scientifically demonstrate the value judgments of the academics that lead and pioneer the society in our country where honor culture is adopted. Therefore, in Turkey, where thousands of women are exposed to violence every year, 877 academics participated in this descriptive study to determine the attitudes of academics toward violence against women in the name of honor. The data were collected using "The Scale for Attitudes Towards Violence Against Women in the Name of Honor (SAVWNH)" in the form of electronic questionnaires through email addresses of the academics working at different faculties of the university in the official website of the university in September 1 to October 1, 2015. In our study, academics' "attitudes towards violence against women in the name of honor" were found low. That is, academics had negative attitudes toward the verbal or physical violence against women in the name of honor and opposed to the punishment of women for this reason. Nevertheless, the attitudes of those who were males; those who were not professors, associate professors, and assistant professors; those who were single; those who had lived in the district/village for a long time; those who had arranged marriages; those who used any kind of violence; and those who considered violence as a solution were found somewhat more conventional. These results showed that, for some academics, the traditional beliefs of the Turkish patriarchal society continued to be valid although they were included in university academic cultures. In fact, it is revealed here that social values, traditions, and customs are very effective and important on the formation of personality in socialization process.

  11. GOLD IS EARNED FROM THE PRODUCTION OF THAI GOLD LEAF

    Directory of Open Access Journals (Sweden)

    Dirk Bax

    2010-06-01

    Full Text Available Thai people like to cover sacred objects or things dear to them with gold leaf.. Statues of Buddha are sometimes covered with so many layers of gold leaf that they become formless figures, that can hardly be recognized. Portraits of beloved ancestors, statues of elephants and grave tombs are often covered with gold leaf. If one considers the number of Thai people and the popularity of the habit, the amount of gold involved could be considerable.

  12. A Team Approach to Enhance Scholarship Among Honors Students in Nursing.

    Science.gov (United States)

    Jukkala, Angela M; Miltner, Rebecca S; Morrison, Shannon L; Gisiger-Camata, Sylvia; Todd, Allison; Moneyham, Linda D; Meneses, Karen M

    2016-01-01

    Honors programs within schools of nursing have the potential to enhance young nurses' interest in developing programs of research early in their careers and can thus contribute to the successful development of nursing knowledge. Such programs also provide opportunities to enhance knowledge and skill in leadership and teamwork at a critical time during the development of their professional nurse identity. This article presents the successful approach one organization took when revising its honors program to meet the current needs of students, society, and the profession.

  13. Activated carbons and gold

    International Nuclear Information System (INIS)

    McDougall, G.J.; Hancock, R.D.

    1980-01-01

    The literature on activated carbon is reviewed so as to provide a general background with respect to the effect of source material and activation procedure on carbon properties, the structure and chemical nature of the surface of the activated carbon, and the nature of absorption processes on carbon. The various theories on the absorption of gold and silver from cyanide solutions are then reviewed, followed by a discussion of processes for the recovery of gold and silver from cyanide solutions using activated carbon, including a comparison with zinc precipitation

  14. Rushing for gold

    DEFF Research Database (Denmark)

    Jønsson, Jesper Bosse; Bryceson, Deborah Fahy

    2009-01-01

    African rural dwellers have faced depressed economic prospects for several decades. Now, in a number of mineral-rich countries, multiple discoveries of gold and precious stones have attracted large numbers of prospective small-scale miners. While their 'rush' to, and activities within, mining sites...... are increasingly being noted, there is little analysis of miners' mobility patterns and material outcomes. In this article, on the basis of a sample survey and interviews at two gold-mining sites in Tanzania, we probe when and why miners leave one site in favour of another. Our findings indicate that movement...

  15. Elevated rates of gold mining in the Amazon revealed through high-resolution monitoring

    Science.gov (United States)

    Asner, Gregory P.; Llactayo, William; Tupayachi, Raul; Luna, Ernesto Ráez

    2013-01-01

    Gold mining has rapidly increased in western Amazonia, but the rates and ecological impacts of mining remain poorly known and potentially underestimated. We combined field surveys, airborne mapping, and high-resolution satellite imaging to assess road- and river-based gold mining in the Madre de Dios region of the Peruvian Amazon from 1999 to 2012. In this period, the geographic extent of gold mining increased 400%. The average annual rate of forest loss as a result of gold mining tripled in 2008 following the global economic recession, closely associated with increased gold prices. Small clandestine operations now comprise more than half of all gold mining activities throughout the region. These rates of gold mining are far higher than previous estimates that were based on traditional satellite mapping techniques. Our results prove that gold mining is growing more rapidly than previously thought, and that high-resolution monitoring approaches are required to accurately quantify human impacts on tropical forests. PMID:24167281

  16. Rethinking Honors Curriculum in Light of the AP/IB/Dual Enrollment Challenge: Innovation and Curricular Flexibility

    Science.gov (United States)

    Coleman, David; Patton, Katie

    2016-01-01

    The authors of this article concede that Annmarie Guzy's lead article for this volume of "Journal of the National Collegiate Honors Council" speaks of a familiar challenge in the Eastern Kentucky University Honors Program. The nearly universal and dramatic increase in the number of AP, IB, and/or Dual Enrollment credit hours among their…

  17. The McBride Honors Program in Public Affairs for Scientists and Engineers

    Science.gov (United States)

    Harrison, W. J.; Miller, R. L.; Olds, B. M.; Sacks, A. B.

    2006-12-01

    The McBride Honors Program in Public Affairs at The Colorado School of Mines (CSM), instituted in 1978, is an award-winning exemplar in the liberal arts which provides a select number of CSM engineering students an opportunity to cross the boundaries of their technical expertise in engineering and applied science, and to gain the understanding and appreciation of the contexts in which engineering and applied science and all human systems reside, and specifically to explore and integrate the social, cultural, ethical and environmental implications of their future professional judgments and their roles as citizens in varied and complex settings. The 27 semester-hour program of seminars, courses, and off-campus activities features small seminars; a cross-disciplinary approach; and opportunities for one-on-one faculty tutorials, instruction and practice in oral and written communication, a Washington, D.C. public policy seminar, a practicum experience (internship or foreign study). Circumstances external to the McBride Program itself, which include the development and growth of the field of Public Affairs nationally and the persistence of legacy courses, have created the need to revitalize and refocus the historically cross-departmental Program. A recent curriculum reform effort has achieved a more thoroughly interdisciplinary learning experience to educate engineers and scientists who, as called for in the National Academy of Engineering's The Engineer of 2020 "will assume leadership positions from which they can serve as positive influences in the making of public policy and in the administration of government and industry". In this presentation we showcase best practices in curriculum reform, exemplified by a seminar in National policy analysis where students and faculty have recently investigated federal science funding decisions in support of natural hazards including earthquakes, tsunamis, wildland fires, and pandemic disease.

  18. 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.

  19. Chladniite: A New Mineral Honoring the Father of Meteoritics

    Science.gov (United States)

    McCoy, T. J.; Steele, I. M.; Keil, K.; Leonard, B. F.; Endress, M.

    1993-07-01

    cell. A total of 17 lines were observed in the powder pattern. Chladniite is hexagonal, R 3(bar), a = 14.967 angstroms, c = 42.595 angstroms, beta = 120 degrees. Attempts to determine the structure of chladniite are in progress. Chladniite is named for Ernst Florens Friedrich Chladni (1756-1827), who is widely regarded as the "Father of Meteoritics." After his initial training as a lawyer, Chladni turned his attention to science, particularly problems in acoustics. He was not, however, able to obtain a permanent position and embarked upon the life of a nomad, traveling among the great cities of Europe lecturing about acoustics. During these travels, he eventually gained an interest in meteoritics. It was Chladni's pioneering book of 1794 that, for the first time, presented strong evidence for an extraterrestrial origin of meteoritic stones and irons [5]. In addition, Chladni argued that meteorites must have been the building blocks of all planets and argued that a large iron core must exist inside the Earth. During his extensive travels, Chladni also established a meteorite collection that can still be seen at Humboldt University in Berlin. It is appropriate that a mineral be named in his honor as we approach the 200th anniversary of the publication of his monumental work. References: [1] McCoy et al. (1993) Meteoritics, in press. [2] Fuchs et al. (1967) GCA, 21, 1711-1719. [3] Araki and Moore (1981) Am. Mineral., 66, 827-842. [4] Livingstone (1980) Min. Mag., 43, 833-836. [5] Chladni (1794) Riga, J. F. Hartknoch (in German); reprinted (with introduction by G. Hoppe) by Akad. Verlagsgesellschaft Geest & Portig K.-G. (1982) (in German).

  20. ['Gold standard', not 'golden standard'

    NARCIS (Netherlands)

    Claassen, J.A.H.R.

    2005-01-01

    In medical literature, both 'gold standard' and 'golden standard' are employed to describe a reference test used for comparison with a novel method. The term 'gold standard' in its current sense in medical research was coined by Rudd in 1979, in reference to the monetary gold standard. In the same

  1. GOLD PRESSURE VESSEL SEAL

    Science.gov (United States)

    Smith, A.E.

    1963-11-26

    An improved seal between the piston and die member of a piston-cylinder type pressure vessel is presented. A layer of gold, of sufficient thickness to provide an interference fit between the piston and die member, is plated on the contacting surface of at least one of the members. (AEC)

  2. Digging for Gold

    Science.gov (United States)

    Waters, John K.

    2012-01-01

    In the case of higher education, the hills are more like mountains of data that "we're accumulating at a ferocious rate," according to Gerry McCartney, CIO of Purdue University (Indiana). "Every higher education institution has this data, but it just sits there like gold in the ground," complains McCartney. Big Data and the new tools people are…

  3. Turning lead into gold

    DEFF Research Database (Denmark)

    Jensen, Steffen Moltrup Ernø

    For years the field of entrepreneurship has been blinded by the alchemical promise of turning lead into gold, of finding the ones most likely to become the next Branson, Zuckerberg or Gates. The promise has been created in the midst of political and scientific agendas where certain individuals...

  4. Gold Nanoparticle Microwave Synthesis

    International Nuclear Information System (INIS)

    Krantz, Kelsie E.; Christian, Jonathan H.; Coopersmith, Kaitlin; Washington II, Aaron L.; Murph, Simona H.

    2016-01-01

    At the nanometer scale, numerous compounds display different properties than those found in bulk material that can prove useful in areas such as medicinal chemistry. Gold nanoparticles, for example, display promise in newly developed hyperthermia therapies for cancer treatment. Currently, gold nanoparticle synthesis is performed via the hot injection technique which has large variability in final particle size and a longer reaction time. One underdeveloped area by which these particles could be produced is through microwave synthesis. To initiate heating, microwaves agitate polar molecules creating a vibration that gives off the heat energy needed. Previous studies have used microwaves for gold nanoparticle synthesis; however, polar solvents were used that partially absorbed incident microwaves, leading to partial thermal heating of the sample rather than taking full advantage of the microwave to solely heat the gold nanoparticle precursors in a non-polar solution. Through this project, microwaves were utilized as the sole heat source, and non-polar solvents were used to explore the effects of microwave heating only as pertains to the precursor material. Our findings show that the use of non-polar solvents allows for more rapid heating as compared to polar solvents, and a reduction in reaction time from 10 minutes to 1 minute; this maximizes the efficiency of the reaction, and allows for reproducibility in the size/shape of the fabricated nanoparticles.

  5. Gold Nanoparticle Microwave Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Krantz, Kelsie E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Christian, Jonathan H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coopersmith, Kaitlin [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Washington, II, Aaron L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Murph, Simona H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-07-27

    At the nanometer scale, numerous compounds display different properties than those found in bulk material that can prove useful in areas such as medicinal chemistry. Gold nanoparticles, for example, display promise in newly developed hyperthermia therapies for cancer treatment. Currently, gold nanoparticle synthesis is performed via the hot injection technique which has large variability in final particle size and a longer reaction time. One underdeveloped area by which these particles could be produced is through microwave synthesis. To initiate heating, microwaves agitate polar molecules creating a vibration that gives off the heat energy needed. Previous studies have used microwaves for gold nanoparticle synthesis; however, polar solvents were used that partially absorbed incident microwaves, leading to partial thermal heating of the sample rather than taking full advantage of the microwave to solely heat the gold nanoparticle precursors in a non-polar solution. Through this project, microwaves were utilized as the sole heat source, and non-polar solvents were used to explore the effects of microwave heating only as pertains to the precursor material. Our findings show that the use of non-polar solvents allows for more rapid heating as compared to polar solvents, and a reduction in reaction time from 10 minutes to 1 minute; this maximizes the efficiency of the reaction, and allows for reproducibility in the size/shape of the fabricated nanoparticles.

  6. Kalopanacis Cortex extract-capped gold nanoparticles activate NRF2 signaling and ameliorate damage in human neuronal SH-SY5Y cells exposed to oxygen–glucose deprivation and reoxygenation

    Directory of Open Access Journals (Sweden)

    Park SY

    2017-06-01

    Full Text Available Sun Young Park,1 Seon Yeong Chae,1,2 Jin Oh Park,2 Kyu Jin Lee,2 Geuntae Park1,2 1Bio-IT Fusion Technology Research Institute, 2Department of Nanofusion Technology, Graduate School, Pusan National University, Busan, Republic of Korea Abstract: Recently, environment-friendly synthesis of gold nanoparticles (GNPs has been extensively explored by biologists and chemists. However, significant research is still required to determine whether “eco-friendly” GNPs are beneficial to human health and to elucidate the molecular mechanisms of their effects on human cells. We used human neuronal SH-SY5Y cells to show that treatment with Kalopanacis Cortex extract-capped GNPs (KC-GNs, prepared via an eco-friendly, fast, one-pot synthetic route, protected neuronal cells against oxygen–glucose deprivation/reoxygenation (OGD/R-induced damage. To prepare GNPs, Kalopanacis Cortex was used without any chemical reducing and stabilizing agents. Ultraviolet–visible spectroscopy showed maximum absorbance at 526 nm owing to KC-GN surface plasmon resonance. Hydrodynamic size (54.02±2.19 nm and zeta potential (-20.3±0.04 mV were determined by dynamic light scattering. The average diameter (41.07±3.05 nm was determined by high-resolution transmission electron microscopy. Energy-dispersive X-ray diffraction spectroscopy and X-ray diffraction confirmed the presence of assembled GNPs. Fourier transform infrared analysis suggested that functional groups such as O–H, C–C, and C–N participated in KC-GN formation. Cell viability assays indicated that KC-GNs restored the viability of OGD/R-treated SH-SY5Y cells. Flow cytometry demonstrated that KC-GNs inhibited the OGD/R-induced reactive oxygen species production and mitochondrial membrane potential disruption. KC-GNs also inhibited the apoptosis of OGD/R-exposed cells. Western blot analysis indicated that the OGD/R-induced cellular apoptosis and simultaneous increases in the expression of cleaved caspase-3, p

  7. Superparamagnetic core/shell GoldMag nanoparticles: size-, concentration- and time-dependent cellular nanotoxicity on human umbilical vein endothelial cells and the suitable conditions for magnetic resonance imaging.

    Science.gov (United States)

    Gong, Mingfu; Yang, Hua; Zhang, Song; Yang, Yan; Zhang, Dong; Qi, Yueyong; Zou, Liguang

    2015-03-25

    GoldMag nanoparticles (GMNPs) possess the properties of colloid gold and superparamagnetic iron oxide nanoparticles, which make them useful for delivery, separation and molecular imaging. However, because of the nanometer effect, GMNPs are highly toxic. Thus, the biosafety of GMNPs should be fully studied prior to their use in biomedicine. The main purpose of this study was to evaluate the nanotoxicity of GMNPs on human umbilical vein endothelial cells (HUVECs) and determine a suitable size, concentration and time for magnetic resonance imaging (MRI). Transmission electron microscopy showed that GMNPs had a typical shell/core structure, and the shell was confirmed to be gold using energy dispersive spectrometer analysis. The average sizes of the 30 and 50 nm GMNPs were 30.65 ± 3.15 and 49.23 ± 5.01 nm, respectively, and the shell thickness were 6.8 ± 0.65 and 8.5 ± 1.36 nm, respectively. Dynamic light scattering showed that the hydrodynamic diameter of the 30 and 50 nm GMNPs were 33.2 ± 2.68 and 53.12 ± 4.56 nm, respectively. The r 2 relaxivity of the 50 nm GMNPs was 98.65 mM(-1) s(-1), whereas it was 80.18 mM(-1) s(-1) for the 30 nm GMNPs. The proliferation, cytoskeleton, migration, tube formation, apoptosis and ROS generation of labeled HUVECs depended on the size and concentration of GMNPs and the time of exposure. Because of the higher labeling rate, the 50 nm GMNPs exhibited a significant increase in nanotoxicity compared with the 30 nm GMNPs at the same concentration and time. At no more than 25 μg/mL and 12 hours, the 50 nm GMNPs exhibited no significant nanotoxicity in HUVECs, whereas no toxicity was observed at 50 μg/mL and 24 hours for the 30 nm GMNPs. These results demonstrated that the nanotoxicity of GMNPs in HUVECs depended on size, concentration and time. Exposure to larger GMNPs with a higher concentration for a longer period of time resulted in a higher labeling rate and ROS level for HUVECs. Coupled with r 2 relaxivity, it was suggested

  8. 16 CFR Appendix to Part 23 - Exemptions Recognized in the Assay for Quality of Gold Alloy, Gold Filled, Gold Overlay, Rolled...

    Science.gov (United States)

    2010-01-01

    ... Quality of Gold Alloy, Gold Filled, Gold Overlay, Rolled Gold Plate, Silver, and Platinum Industry...—Exemptions Recognized in the Assay for Quality of Gold Alloy, Gold Filled, Gold Overlay, Rolled Gold Plate... in any assay for quality of a karat gold industry product include springs, posts, and separable backs...

  9. The Quest for Honor and Citizenship in Post-Slavery Borgu (Benin)

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi

    2015-01-01

    that is increasingly being contested in a number of forms. The paper explores the heritage of slavery in its cultural, spatial, social, economic, and political dimensions. The author sheds light on the concept of honor that is a central dimension of social and political life in West Africa. In nowadays Benin, Gando...

  10. Honoring and Building on the Rich Literacy Practices of Young Bilingual and Multilingual Learners

    Science.gov (United States)

    Souto-Manning, Mariana

    2016-01-01

    In this article, the author invites teachers of children who are bilingual, multilingual, and at promise for bi-/multilingualism to honor and build on their rich literacy practices. To do so, she challenges ideas and labels that continuously disempower bilingual and multilingual learners. Souto-Manning establishes the understanding that education…

  11. The Honorable Dr Adolfo Urso, Vice Minister for Foreign Trade, "Viceministro delle Attivita' Produttive, Italia"

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    Photo 01: The Honorable Dr Adolfo Urso, Deputy Minister for Productive Activities, Italy, visiting SM18 with (from l to r): Dr Roberto Saban, Technical Coordination and Planning, LHC machine; Prof. Luciano Maiani, CERN Director-General; Dr Mario Gerbino, Director General of the Ministry and Prof. Lucio Rossi, LHC Main Magnet and Superconductors (MMS) Group Leader. Photo 02: Prof. Luciano Maiani, CERN Director-General and The Honorable Dr Adolfo Urso, Deputy Minister for Productive Activities, Italy, in front of one of the LHC superconducting magnet in SM18. Photo 03 :In front of one of the LHC superconducting magnets - from left to right Dr Roberto Saban, Technical Coordination and Planning, LHC machine; The Honorable Dr Adolfo Urso, Deputy Minister for Productive Activities, Italy and Prof. Luciano Maiani, CERN Director-General. Photo 04: In the SM18 hall (from l. to r.) Prof. Luciano Maiani, CERN Director-General, The Honorable Dr Adolfo Urso, Deputy Minister for Productive Activities, Italy and Dr Mario Ge...

  12. Too Smart to Fail: Perceptions of Asian American Students' Experiences in a Collegiate Honors Program

    Science.gov (United States)

    Henfield, Malik S.; Woo, Hongryun; Lin, Yi-Chun; Rausch, Meredith A.

    2014-01-01

    There is a considerable history of misunderstandings associated with Asian American in education. Although many educators and scholars have begun to pay more attention to unique issues associated with this population, studies exploring these students' experiences as honors students in collegiate contexts are scant in the educational literature.…

  13. Pembangunan Aplikasi Perhitungan Honor dan Pengukuran Kinerja Asisten Praktikum Berbasis SaaS

    Directory of Open Access Journals (Sweden)

    Fitri Susanti

    2015-11-01

    Full Text Available Bagi suatu perguruan tinggi, kegiatan praktikum sangat penting untuk mendukung pembelajaran di kelas. Beberapa masalah yang muncul dalam pengelolaan kegiatan praktikum seperti keterlambatan pengumpulan berita acara praktikum (BAP sehingga memperlambat perhitungan, pembayaran dan pelaporan honor asprak. Dibutuhkan waktu sekitar dua minggu untuk rekapitulasi dan validasi ratusan lembar BAP yang telah terkumpul setiap bulannya. Dibutuhkan pengolahan data lebih lanjut untuk menilai kinerja asprak berdasarkan data BAP. Untuk mengatasi permasalahan di atas maka dibangun aplikasi perhitungan honor dan kinerja asprak. Aplikasi ini digunakan untuk mengelola data BAP, perhitungan dan pelaporan honor, perhitungan nilai transkrip aktivitas kemahasiswaan (TAK dan pencetakan sertifikat asprak. Keterbatasan SDM atau biaya menyebabkan tidak semua perguruan tinggi dapat langsung membuat aplikasi yang dibutuhkan. Oleh karena itu aplikasi ini dibangun berbasis Software as A Service (SaaS. Aplikasi ini dikembangkan dengan metode analisis perancangan terstruktur dengan model waterfall. Pengumpulan data kebutuhan aplikasi dilakukan dengan survey ke fakultas-fakultas di Universitas Telkom. Hasilnya dianalisis dan dikembangkan menjadi rancangan aplikasi. Aplikasi diimplementasikan pada pemrograman PHP. Pengujian dilakukan dengan metode black box testing. Hasilnya berupa aplikasi SaaS untuk perhitungan honor dan pengukuran kinerja asisten praktikum. Perguruan tinggi pengguna aplikasi SaaS ini dapat melakukan kostumisasi terhadap fitur yang ada sesuai dengan kebutuhan.

  14. Playing with Light: Adventures in Optics and Spectroscopy for Honors and Majors General Chemistry

    Science.gov (United States)

    van Staveren, Marie N.; Edwards, Kimberly D.; Apkarian, V. A.

    2012-01-01

    A lab was developed for use in an undergraduate honors and majors general chemistry laboratory to introduce students to optics, spectroscopy, and the underlying principles of quantum mechanics. This lab includes four mini-experiments exploring total internal reflection, the tunneling of light, spectra of sparklers and colored candles, and emission…

  15. An Investigation of Student Psychological Wellbeing: Honors versus Nonhonors Undergraduate Education

    Science.gov (United States)

    Plominski, Abigail P.; Burns, Lawrence R.

    2018-01-01

    The purpose of this study was to describe the current state of psychological wellbeing in gifted and nongifted undergraduate student sample populations and identify undergraduate populations experiencing heightened levels of distress within a large Midwestern public university. Study participants included 641 honors and 386 nonhonors undergraduate…

  16. Mobile Engagement at Scottsdale Community College: The Apple iPad in an English Honors Class

    Science.gov (United States)

    Tualla, Larry Tech

    2011-01-01

    This dissertation reports on an action research study that sought to discover how a new WiFi, tablet computing device, the Apple iPad, affected, enhanced, and impacted student engagement in an English Honors course at Scottsdale Community College. The researcher was also the instructor in the two semester, first-year, college composition sequence…

  17. Honoring the Personal Response: A Strategy for Serving the Public Hunger for Connection

    Science.gov (United States)

    Williams, Ray

    2010-01-01

    Many groups of adult museum visitors welcome the invitation to make personal connections to works of art. Time for individual reflection and sharing with others may enable relationships to deepen and new insights to emerge. This article describes an approach to gallery teaching that honors the memories, associations, and emotions that visitors…

  18. Hydrology of soils and aquifers: A special issue in honor of Garrison Sposito

    Science.gov (United States)

    Lo, WeiCheng; Baveye, Philippe C.; Charlet, Laurent

    2017-08-01

    This Special Issue of Advances in Water Resources is dedicated to Professor Garrison Sposito (Fig. 1) in honor of his great achievements and outstanding contributions to the hydrology and geochemistry of soils and aquifers, as well as in celebration on the occasion of his retirement from the University of California at Berkeley.

  19. When Poetry became Ethnography and Other Flying Pig Tales in Honor of Dell Hymes

    Science.gov (United States)

    Cahnmann-Taylor, Melisa

    2011-01-01

    Cahnmann-Taylor remembers her first encounter with Dell Hymes at an open mic event at the annual meeting of the American Anthropological Association. She puzzles his complex stance on the role ethnographic poems might play in one's ethnographic project. In Dell Hymes's honor, she shares a poetic rendering of a speech event from her bilingual…

  20. A Comparison of Burnout among Honors, Regular Education, and Special Education K-8 Teachers

    Science.gov (United States)

    Sharpe, Christopher

    2017-01-01

    This study employed a quantitative, ex-post facto non-experimental design to examine the effect of whether teaching honors, regular, or special education classes in either an elementary or middle school setting influenced the experience of teacher burnout. Participants included 69 teachers from two counties in a Southern state. The study survey…

  1. Setting the Table for Diversity. National Collegiate Honors Council Monograph Series

    Science.gov (United States)

    Coleman, Lisa L., Ed.; Kotinek, Jonathan D., Ed.

    2010-01-01

    This monograph provides a cross section of policy and practice through the voices and experiences of honors faculty, staff, and students from across the nation. While far from comprehensive, this volume does pick up different strands of thinking on diversity to present a rich and complicated understanding of what diversity is, why it is important,…

  2. A Legacy of Sacrifice and Honor: Celebrating Tribal Resilience and Military Service at Haskell Nations University

    Science.gov (United States)

    Warrington, Jacinta

    2017-01-01

    Haskell Indian Nations University opened 133 years ago, on September 17, 1884, as the U.S. Training and Industrial School--one of three original tribal boarding schools funded by the United States Congress. Three years later the school changed its name to Haskell Institute in honor of Chase Dudley Haskell, a U.S. representative from the Second…

  3. Highlighting the Transfer, Honors, and Excellence Workshop. CSCC Bulletin, Issue 7, 1983.

    Science.gov (United States)

    Center for the Study of Community Colleges, Los Angeles, CA.

    Summaries are provided for the major presentations given at a workshop on honors, transfer, and excellence, held in Los Angeles in October 1982. Following a brief overview of the main topics covered, highlights are presented from the talks of: (1) Robert McCabe, president of Miami-Dade Community College (MDCC), who urged participants to set high…

  4. Honoring the Past, Changing the Future: Bringing Native American Voices into Dance Theory Courses

    Science.gov (United States)

    Prichard, Robin

    2016-01-01

    The inclusion of Native American perspectives adds an important voice in honoring the multiplicities of histories and cultures inherent in American society. And yet, teachers run the risk of committing unknown offenses if they are not familiar with the potential pitfalls that longstanding asymmetrical power relations between cultures can produce.…

  5. Moessbauerspectroscopy on Gold Ruby Glass

    International Nuclear Information System (INIS)

    Haslbeck, S.

    2005-01-01

    In this thesis, the chemical states of gold and the physical mechanisms of the growing process of the particles under the influence of additional ingredients like tin, lead, antimony and selenium before, during and after the colouring process are investigated by using the Moessbauer spectroscopy on 197 Au, 119 Sn and 121 Sb, optical spectroscopy and X-ray-diffraction. Gold in an unnealed, colourless state of the glasses consists of monovalent forming linear bonds to two neighbouring oxygen atoms. The Lamb-Moessbauer factor of these gold oxide bondings is observed as 0.095 at 4.2 K. The gold in it's oxide state transforms to gold particles with a diameter of 3 nm to 60 nm. The size of the gold particles is quite definable within the optical spectra and certain sizes are also discernable within the Moessbauer spectra. One component of the Moessbauer spectra is assigned to the surface layer of the gold particles. By comparing this surface component with the amount of the bulk metallic core, one can calculate the size of the gold particles. In the Moessbauer spectra of the colourless glass one also can find parts of bulk metallic gold. Investigations with X-ray diffraction show that these are gold particles with a diameter of 100 nm to 300 nm and therefore have no additional colouring effect within the visible spectrum. The Moessbauer spectra on gold of the remelt glasses are similar to those which have been measured on the initial colourless glasses

  6. For the love of gold

    International Nuclear Information System (INIS)

    Young, J.E.

    1993-01-01

    Gold is found in minute quantities and gold mining generates enormous amounts of waste materials and long history of environmental destruction: mercury in tailing, eroded land, and acid mine drainage are legacies of the past. The problem has become worse in recent years in North America, Australia, the Amazon basin, Philippines. This paper describes the economics of gold and the changes in the world economy which has precipitated the new gold rushes. Current technology uses a cyanide solution for leaching small amounts of gold from tons of waste, and mercury remains a toxic waste of gold mining. Both short and long term results of gold mining, on the environment and on indiginous populations are described

  7. The RHIC gold rush

    CERN Document Server

    Schäfer, T

    2003-01-01

    Physicists are colliding gold nuclei to recreate the fireball that existed in the very early universe, and they may have found evidence for quark-gluon plasma. What happens to ordinary matter as you heat it to higher and higher temperatures, or compress it to greater and greater densities? This simple question underpins a major effort to create extreme conditions in the lab, which has recently taken the shape of the Relativistic Heavy Ion Collider (RHIC). This machine has been colliding gold nuclei since 2000, and has produced tantalizing hints that a new state of matter - the quark-gluon plasma - is created in the reactions. But it has also sparked surprises that are sending researchers back to the drawing board. (U.K.)

  8. The golden age: gold nanoparticles for biomedicine†

    Science.gov (United States)

    Dreaden, Erik C.; Alkilany, Alaaldin M.; Huang, Xiaohua; Murphy, Catherine J.; El-Sayed, Mostafa A.

    2018-01-01

    Gold nanoparticles have been used in biomedical applications since their first colloidal syntheses more than three centuries ago. However, over the past two decades, their beautiful colors and unique electronic properties have also attracted tremendous attention due to their historical applications in art and ancient medicine and current applications in enhanced optoelectronics and photovoltaics. In spite of their modest alchemical beginnings, gold nanoparticles exhibit physical properties that are truly different from both small molecules and bulk materials, as well as from other nanoscale particles. Their unique combination of properties is just beginning to be fully realized in range of medical diagnostic and therapeutic applications. This critical review will provide insights into the design, synthesis, functionalization, and applications of these artificial molecules in biomedicine and discuss their tailored interactions with biological systems to achieve improved patient health. Further, we provide a survey of the rapidly expanding body of literature on this topic and argue that gold nanotechnology-enabled biomedicine is not simply an act of ‘gilding the (nanomedicinal) lily’, but that a new ‘Golden Age’ of biomedical nanotechnology is truly upon us. Moving forward, the most challenging nanoscience ahead of us will be to find new chemical and physical methods of functionalizing gold nanoparticles with compounds that can promote efficient binding, clearance, and biocompatibility and to assess their safety to other biological systems and their long-term term effects on human health and reproduction (472 references). PMID:22109657

  9. Radioactive gold ring dermatitis

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.A.; Aldrich, J.E. (Dalhousie Univ., Halifax, Nova Scotia (Canada))

    1990-08-01

    A superficial squamous cell carcinoma developed in a woman who wore a radioactive gold ring for more than 30 years. Only part of the ring was radioactive. Radiation dose measurements indicated that the dose to basal skin layer was 2.4 Gy (240 rad) per week. If it is assumed that the woman continually wore her wedding ring for 37 years since purchase, she would have received a maximum dose of approximately 4600 Gy.

  10. Radioactive gold ring dermatitis

    International Nuclear Information System (INIS)

    Miller, R.A.; Aldrich, J.E.

    1990-01-01

    A superficial squamous cell carcinoma developed in a woman who wore a radioactive gold ring for more than 30 years. Only part of the ring was radioactive. Radiation dose measurements indicated that the dose to basal skin layer was 2.4 Gy (240 rad) per week. If it is assumed that the woman continually wore her wedding ring for 37 years since purchase, she would have received a maximum dose of approximately 4600 Gy

  11. Gold, nickel and copper mining and processing.

    Science.gov (United States)

    Lightfoot, Nancy E; Pacey, Michael A; Darling, Shelley

    2010-01-01

    Ore mining occurs in all Canadian provinces and territories except Prince Edward Island. Ores include bauxite, copper, gold, iron, lead and zinc. Workers in metal mining and processing are exposed, not only to the metal of interest, but also to various other substances prevalent in the industry, such as diesel emissions, oil mists, blasting agents, silica, radon, and arsenic. This chapter examines cancer risk related to the mining of gold, nickel and copper. The human carcinogenicity of nickel depends upon the species of nickel, its concentration and the route of exposure. Exposure to nickel or nickel compounds via routes other than inhalation has not been shown to increase cancer risk in humans. As such, cancer sites of concern include the lung, and the nasal sinus. Evidence comes from studies of nickel refinery and leaching, calcining, and sintering workers in the early half of the 20th century. There appears to be little or no detectable risk in most sectors of the nickel industry at current exposure levels. The general population risk from the extremely small concentrations detectable in ambient air are negligible. Nevertheless, animal carcinogenesis studies, studies of nickel carcinogenesis mechanisms, and epidemiological studies with quantitative exposure assessment of various nickel species would enhance our understanding of human health risks associated with nickel. Definitive conclusions linking cancer to exposures in gold and copper mining and processing are not possible at this time. The available results appear to demand additional study of a variety of potential occupational and non-occupational risk factors.

  12. Direct evidence of oxidized gold on supported gold catalysts.

    Science.gov (United States)

    Fu, L; Wu, N Q; Yang, J H; Qu, F; Johnson, D L; Kung, M C; Kung, H H; Dravid, V P

    2005-03-10

    Supported gold catalysts have drawn worldwide interest due to the novel properties and potential applications in industries. However, the origin of the catalytic activity in gold nanoparticles is still not well understood. In this study, time-of-flight secondary ion mass spectroscopy (TOF-SIMS) has been applied to investigate the nature of gold in Au (1.3 wt %)/gamma-Al2O3 and Au (2.8 wt %)/TiO2 catalysts prepared by the deposition-precipitation method. The SIMS spectrum of the supported gold catalysts presented AuO-, AuO2-, and AuOH- ion clusters. These measurements show direct evidence for oxidized gold on supported gold catalysts and may be helpful to gaining better understanding of the origin of the catalytic activity.

  13. Ginseng-berry-mediated gold and silver nanoparticle synthesis and evaluation of their in vitro antioxidant, antimicrobial, and cytotoxicity effects on human dermal fibroblast and murine melanoma skin cell lines

    Science.gov (United States)

    Jiménez Pérez, Zuly Elizabeth; Mathiyalagan, Ramya; Markus, Josua; Kim, Yeon-Ju; Kang, Hyun Mi; Abbai, Ragavendran; Seo, Kwang Hoon; Wang, Dandan; Soshnikova, Veronika; Yang, Deok Chun

    2017-01-01

    There has been a growing interest in the design of environmentally affable and biocompatible nanoparticles among scientists to find novel and safe biomaterials. Panax ginseng Meyer berries have unique phytochemical profile and exhibit beneficial pharmacological activities such as antihyperglycemic, antiobesity, antiaging, and antioxidant properties. A comprehensive study of the biologically active compounds in ginseng berry extract (GBE) and the ability of ginseng berry (GB) as novel material for the biosynthesis of gold nanoparticles (GBAuNPs) and silver nanoparticles (GBAgNPs) was conducted. In addition, the effects of GBAuNPs and GBAgNPs on skin cell lines for further potential biological applications are highlighted. GBAuNPs and GBAgNPs were synthesized using aqueous GBE as a reducing and capping agent. The synthesized nanoparticles were characterized for their size, morphology, and crystallinity. The nanoparticles were evaluated for antioxidant, anti-tyrosinase, antibacterial, and cytotoxicity activities and for morphological changes in human dermal fibroblast and murine melanoma skin cell lines. The phytochemicals contained in GBE effectively reduced and capped gold and silver ions to form GBAuNPs and GBAgNPs. The optimal synthesis conditions (ie, temperature and v/v % of GBE) and kinetics were investigated. Polysaccharides and phenolic compounds present in GBE were suggested to be responsible for stabilization and functionalization of nanoparticles. GBAuNPs and GBAgNPs showed increased scavenging activity against 2,2-diphenyl-1-picrylhydrazyl free radicals compared to GBE. GBAuNPs and GBAgNPs effectively inhibited mushroom tyrosinase, while GBAgNPs showed antibacterial activity against Escherichia coli and Staphylococcus aureus. In addition, GBAuNPs were nontoxic to human dermal fibroblast and murine melanoma cell lines, and GBAgNPs showed cytotoxic effect on murine melanoma cell lines. The current results evidently suggest that GBAgNPs can act as potential

  14. Wild Justice: Honor and Fairness among Beasts at Play

    Science.gov (United States)

    Bekoff, Marc; Pierce, Jessica

    2009-01-01

    This essay challenges science's traditional taboo against anthropomorphizing animals or considering their behavior as indicative of feelings similar to human emotions. In their new book "Wild Justice: The Moral Lives of Animals," the authors argue that anthropomorphism is alive and well, as it should be. Here they describe some…

  15. Gold--a controversial sensitizer

    DEFF Research Database (Denmark)

    Bruze, M; Andersen, Klaus Ejner

    1999-01-01

    of clinical relevance, i.e., causing or aggravating a contact dermatitis. In this paper, these steps are discussed with regard to gold. With our present knowledge of contact allergy-allergic contact dermatitis, we do not recommend including gold sodium thiosulfate in the standard series. It should be applied......Until recently, gold allergy was considered to be extremely rare. Gold has been used and worshipped for thousands of years without any obvious complaints of skin problems, either in those participating in mining and other ways of prospecting, or in those wearing jewellery. When studies on contact...... allergy to gold sodium thiosulfate were published at the beginning of the 1990s, the allergic nature of the reported positive patch test reactions to gold was questioned. The major argument for such questioning was the lack of demonstrable clinical relevance in most positive reactors. A major reason...

  16. Extracellular mycosynthesis of gold nanoparticles using Fusarium solani

    Science.gov (United States)

    Gopinath, K.; Arumugam, A.

    2014-08-01

    The development of eco-friendly methods for the synthesis of nanomaterial shape and size is an important area of research in the field of nanotechnology. The present investigation deals with the extracellular rapid biosynthesis of gold nanoparticles using Fusarium solani culture filtrate. The UV-vis spectra of the fungal culture filtrate medium containing gold ion showed peak at 527 nm corresponding to the plasmon absorbance of gold nanoparticles. FTIR spectra provide an evidence for the presence of heterocyclic compound in the culture filtrate, which increases the stability of the synthesized gold nanoparticles. The X-ray analysis respects the Bragg's law and confirmed the crystalline nature of the gold nanoparticles. AFM analysis showed the results of particle sizes (41 nm). Transmission electron microscopy (TEM) showed that the gold nanoparticles are spherical in shape with the size range from 20 to 50 nm. The use of F. solani will offer several advantages since it is considered as a non-human pathogenic organism. The fungus F. solani has a fast growth rate, rapid capacity of metallic ions reduction, NPs stabilization and facile and economical biomass handling. Extracellular biosynthesis of gold nanoparticles could be highly advantageous from the point of view of synthesis in large quantities, time consumption, eco-friendly, non-toxic and easy downstream processing.

  17. Immunological properties of gold nanoparticles.

    Science.gov (United States)

    Dykman, Lev A; Khlebtsov, Nikolai G

    2017-03-01

    In the past decade, gold nanoparticles have attracted strong interest from the nanobiotechnological community owing to the significant progress made in robust and easy-to-make synthesis technologies, in surface functionalization, and in promising biomedical applications. These include bioimaging, gene diagnostics, analytical sensing, photothermal treatment of tumors, and targeted delivery of various biomolecular and chemical cargos. For the last-named application, gold nanoparticles should be properly fabricated to deliver the cargo into the targeted cells through effective endocytosis. In this review, we discuss recent progress in understanding the selective penetration of gold nanoparticles into immune cells. The interaction of gold nanoparticles with immune cell receptors is discussed. As distinct from other published reviews, we present a summary of the immunological properties of gold nanoparticles. This review also summarizes what is known about the application of gold nanoparticles as an antigen carrier and adjuvant in immunization for the preparation of antibodies in vivo . For each of the above topics, the basic principles, recent advances, and current challenges are discussed. Thus, this review presents a detailed analysis of data on interaction of gold nanoparticles with immune cells. Emphasis is placed on the systematization of data over production of antibodies by using gold nanoparticles and adjuvant properties of gold nanoparticles. Specifically, we start our discussion with current data on interaction of various gold nanoparticles with immune cells. The next section describes existing technologies to improve production of antibodies in vivo by using gold nanoparticles conjugated with specific ligands. Finally, we describe what is known about adjuvant properties of bare gold or functionalized nanoparticles. In the Conclusion section, we present a short summary of reported data and some challenges and perspectives.

  18. Bats, cyanide, and gold mining

    Science.gov (United States)

    Clark, Donald R.

    1991-01-01

    Although the boom days of prospectors and gold nuggets are long gone, modern technology enables gold to continue to be extracted from ore. Unfortunately, the extraction method has often been disastrous for bats and other wildlife, an issue I first became aware of in early 1989. Phone calls from Drs. Merlin Tuttle and Elizabeth Pierson, a BCI member and bat researcher from Berkeley, California, alerted me that bats were dying from apparent cyanide poisoning at gold mines in the western United States.

  19. GoldMag nanoparticles with core/shell structure: characterization and application in MR molecular imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Song; Zou Liguang, E-mail: kxyjzy@yahoo.cn; Zhang Dong; Pang Xin; Yang Hua [Xinqiao Hospital, Third Military Medical University, Department of Radiology (China); Xu Ying [Xinqiao Hospital, Third Military Medical University, Base for Drug Clinical Trial (China)

    2011-09-15

    GoldMag is a kind of bi-functional nanoparticle, composed of a gold nanoshell and an iron oxide core. GoldMag combines the antibody immobilization property of gold nanoshell with the superparamagnetic feature of the iron oxide core. Rabbit anti-mouse IgG was immobilized on the surface of GoldMag to synthesize GoldMag-IgG in a single-step process. Transmission electron microscopy, UV/Vis spectrophotometry, zeta potential analysis, dynamic light scattering, enzyme-linked immunosorbent assay, and magnetic resonance imaging (MRI) were employed to characterize the nanostructures and the spectroscopic and magnetic properties of GoldMag and GoldMag-IgG. The antibody encapsulation efficiency of GoldMag was measured as 58.7%, and the antibody loading capacity was 88 {mu}g IgG per milligram of GoldMag. The immunoactivity of GoldMag-IgG was estimated to be 43.3% of that of the original IgG. The cytotoxicity of GoldMag was assessed by MTT assay, which showed that it has only little influence on human dermal lymphatic endothelial cells. MR imaging of different concentrations of ultrasmall superparamagnetic iron oxide, GoldMag, and GoldMag-IgG showed that 3 {mu}g/mL of nanoparticles could significantly affect the MRI signal intensity of GRE T2*WI. The results demonstrate that GoldMag nanoparticles can be effectively conjugated with biomacromolecules and possess great potential for MR molecular imaging.

  20. Gene expression profiling of macrophages: implications for an immunosuppressive effect of dissolucytotic gold ions

    Directory of Open Access Journals (Sweden)

    Seifert Oliver

    2012-11-01

    Full Text Available Abstract Background Gold salts has previously been used in the treatment of rheumatoid arthritis but have been replaced by biologicals such as TNF-α inhibitors. The mechanisms behind the anti-inflammatory effect of metallic gold ions are still unknown, however, recent data showed that charged gold atoms are released from pure metallic gold implants by macrophages via a dissolucytosis membrane, and that gold ions are taken up by local macrophages, mast cells and to some extent fibroblasts. These findings open the question of possible immunomodulatory effects of metallic gold and motivate efforts on a deeper understanding of the effect of metallic gold on key inflammatory cells as macrophages. Methods Human macrophage cells (cell line THP-1 were grown on gold foils and intracellular uptake was analysed by autometallography. The impact of phagocytised gold ions on viability of THP-1 cells was investigated by trypan blue staining and TUNEL assay. The global gene expression profile of THP-1 cells after incorporation of gold ions was studied using microarray analysis comprising approximately 20,000 genes. The gene expression data was confirmed by measurement of secreted proteins. Results Autometallography showed intracellular uptake of gold ions into THP-1 cells. No significant effect on viability of THP-1 cells was demonstrated. Our data revealed a unique gene expression signature of dissolucytotic THP-1 cells that had taken up gold ions. A large number of regulated genes were functionally related to immunomodulation. Gold ion uptake induced downregulation of genes involved in rheumatoid arthritis such as hepatocyte growth factor, tenascin-C, inhibitor of DNA binding 1 and 3 and matrix metalloproteinase 13. Conclusion The data obtained in this study offer new insights into the mode of action of gold ions and suggest for the investigation of effects on other key cells and a possible future role of metallic gold as implants in rheumatoid arthritis or

  1. The extractive metallurgy of gold

    Energy Technology Data Exchange (ETDEWEB)

    Kongolo, K.; Mwema, M.D. [University of Lubumbashi, Zaire, Gecamines Metallurgical Research Centre, Likasi, Zaire, c/o Gecamines Brussels (Belgium)

    1998-12-15

    Moessbauer spectroscopy has been successfully used in investigation of the gold compounds present in ores and the gold species which occur during the process metallurgy of this metal. This paper is a survey of the basic recovery methods and techniques used in extractive metallurgy of gold. Process fundamentals on mineral processing, ore leaching, zinc dust cementation, adsorption on activated carbon, electrowinning and refining are examined. The recovery of gold as a by-product of the copper industry is also described. Alternative processing methods are indicated in order to shed light on new interesting research topics where Moessbauer spectroscopy could be applied.

  2. The extractive metallurgy of gold

    International Nuclear Information System (INIS)

    Kongolo, K.; Mwema, M.D.

    1998-01-01

    Moessbauer spectroscopy has been successfully used in investigation of the gold compounds present in ores and the gold species which occur during the process metallurgy of this metal. This paper is a survey of the basic recovery methods and techniques used in extractive metallurgy of gold. Process fundamentals on mineral processing, ore leaching, zinc dust cementation, adsorption on activated carbon, electrowinning and refining are examined. The recovery of gold as a by-product of the copper industry is also described. Alternative processing methods are indicated in order to shed light on new interesting research topics where Moessbauer spectroscopy could be applied

  3. Surface-stabilized gold nanocatalysts

    Science.gov (United States)

    Dai, Sheng [Knoxville, TN; Yan, Wenfu [Oak Ridge, TN

    2009-12-08

    A surface-stabilized gold nanocatalyst includes a solid support having stabilizing surfaces for supporting gold nanoparticles, and a plurality of gold nanoparticles having an average particle size of less than 8 nm disposed on the stabilizing surfaces. The surface-stabilized gold nanocatalyst provides enhanced stability, such as at high temperature under oxygen containing environments. In one embodiment, the solid support is a multi-layer support comprising at least a first layer having a second layer providing the stabilizing surfaces disposed thereon, the first and second layer being chemically distinct.

  4. Enzymatic biosensor based on entrapment of d-amino acid oxidase on gold nanofilm/MWCNTs nanocomposite modified glassy carbon electrode by sol-gel network: Analytical applications for d-alanine in human serum.

    Science.gov (United States)

    Shoja, Yalda; Rafati, Amir Abbas; Ghodsi, Javad

    2017-05-01

    Sensing and determination of d-alanine is studied by using an enzymatic biosensor which was constructed on the basis of d-amino acid oxidase (DAAO) immobilization by sol-gel film onto glassy carbon electrode surface modified with nanocomposite of gold nanofilm (Au-NF) and multiwalled carbon nanotubes (MWCNTs). The Au-NF/MWCNT nanocomposite was prepared by applying the potentiostatic technique for electrodeposition of Au-NF on the MWCNT immobilized on glassy carbon electrode surface. The modified electrode is investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), linear sweep voltammetry (LSV) and cyclic voltammetry(CV) techniques. The linear sweep voltammetry was used for determination of d-alanine and the results showed an excellent linear relationship between biosensor response and d-alanine concentration ranging from 0.25μM to 4.5μM with correction coefficient of 0.999 (n=20). Detection limit for the fabricated sensor was calculated about 20nM (for S/N=3) and sensitivity was about 56.1μAμM -1 cm -2 . The developed biosensor exhibited rapid and accurate response to d-alanine, a good stability (4 weeks) and an average recovery of 98.9% in human serum samples. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Visit of the Honorable Madeleine M. Kunin, Ambassador of the United States to Switzerland and Mr. David Jaberg, Political Officer

    CERN Multimedia

    Patrice Loiez

    1998-01-01

    Photo 01 : The Honorable M. Kunin, Ambassador of the United States of Switzerland signs the Guest Book with the Director General C.H. Llewellyn Smith. Photo 03 : with M. Michel Della Negra. Photo 07 : with Peter Jenni, ATLAS spokesman.

  6. De la difusión cultural de la virtud caballeresca a la defensa del honor

    Directory of Open Access Journals (Sweden)

    Remedios Morán Martín

    2000-01-01

    Full Text Available A medida que la nobleza va perdiendo su carácter guerrero (bellatores, empieza a elaborar un concepto de virtud y de honor cercano a las nuevas corrientes humanistas que se difunden en la Península, lo que conlleva unas nuevas formas de defensa del honor como práctica social, que desembocarán en la tipificación del duelo como delito.As the same time as Nobility is on the way to lose its warlike attitude (bellatores, it begins to elabórate a new concept of virtue and honour cióse to the new humanistic tendencies spread in the Iberian Península, what implles new ways to defend the honour as a social practico, which wlll lead to the typification of the duel as an offense.

  7. Os honorários de sucumbência e o advogado público

    OpenAIRE

    Muraro, Rosa Branca

    2013-01-01

    O presente trabalho tem como objetivo principal analisar a vedação estabelecida ao advogado público em receber honorários de sucumbência decorrentes das ações em que patrocina interesses da Fazenda Pública. Referida proibição, além de ser oriunda do princípio da Indisponibilidade do Interesse Público, decorre das disposições estabelecidas pelo artigo 4° da Lei Federal n° 9.527/97. De outro norte, o presente estudo faz uma abordagem sobre a destinação dos honorários de sucumbência adotada pelo...

  8. Determining gold content

    International Nuclear Information System (INIS)

    Clayton, C.G.; Wormald, M.R.

    1981-01-01

    A method for determining the gold content of a material, comprises irradiating a body of the material with neutrons and determining the intensity of γ-rays having an energy of 279 keV arising from the reaction 179 Au(nn') 179 Au → 279 keV. The apparatus has means for conveying the materials past an assembly, which has a neutron source, which does not produce neutrons having sufficient energy to excite fast neutron reactions in non-auriferous constituents. (author)

  9. 31 CFR 100.4 - Gold coin and gold certificates in general.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Gold coin and gold certificates in... EXCHANGE OF PAPER CURRENCY AND COIN In General § 100.4 Gold coin and gold certificates in general. Gold coins, and gold certificates of the type issued before January 30, 1934, are exchangeable, as provided...

  10. Mercury use in small scale gold mining in Ghana: an assessment of its impact on miners

    International Nuclear Information System (INIS)

    Biagya, Robert Yakubu

    2002-12-01

    Small scale gold mining is responsible for about 5% of Ghana’s annual gold production. It is estimated that between 80,000 and 100,000 people are engaged in small scale gold mining either on part-time or permanent basis. Amalgamation is the preferred method used by small scale gold miners for extracting free gold from its ores. The rate at which mercury, an important input in this method, is discharged into the atmosphere and water bodies is alarming. This research describes the various mining and processing methods in small scale gold mining and the extent of mercury use and releases to the environment. It discusses mercury and its human and environmental effects. It defines the various forms of mercury, routes of exposure, toxic effects. The levels of exposure to mercury by all groups of small scale gold miners are determined, and the impacts on the miners and the environment are assessed. It concludes that: • Mercury is mainly released into the environment as a result of small scale gold mining through spillage of elemental mercury and evaporation of mercury from the amalgam and sponge gold when they are heated on open fire. • Mercury in environmental samples from small scale gold mining areas is well above standard limit values. • Mercury released into the environment through small scale gold mining impacts negatively on the miners themselves and the general environment. Finally, it recommends the need for the adoption of mercury emission reduction strategies for dealing with the mercury problem. (au)

  11. Determination of Gold from Gold Matrix of North Western Nigeria ...

    African Journals Online (AJOL)

    The research paper presents analytical results of Au, Mn and V concentrations of some Nigerian gold ores using two techniques: epithermal neutron activation analysis (ENAA) and proton induced X-ray emission (PIXE). Fourteen samples were collected from gold fields of North Western Nigeria, prepared separately to a ...

  12. CUANDO LAS AFRENTAS SE LAVABAN CON SANGRE: HONOR, MASCULINIDAD Y DUELOS DE ESPADAS EN EL SIGLO XVIII CHILENO

    Directory of Open Access Journals (Sweden)

    Verónica Undurraga Schüler

    2008-06-01

    Full Text Available Este trabajo aborda la relación entre honor y prácticas sociales en el siglo XVIII chileno, analizando la figura de los duelos o expresiones de violencia masculina formalizada. Junto con indagar en los mecanismos restitutorios del honor y su vinculación a los fundamentos de una masculinidad tradicional, reflexiona sobre las gamas de manejo social de dicho valor en el período señalado. Teóricamente se rescatan los aportes de la antropología y se hace un balance del tratamiento historiográfico del problema. Desde los registros judiciales se plantea el carácter transversal del honor en términos sociales y se aborda su "doble naturaleza" en cuanto espacio relacional y ámbito de confrontación de los individuos.This works deals with the relationship between honor and social practices in Chile's eighteenth century and analyzes formal duels or expressions of legalized masculine violence. This article explores various manifestations of the social ways used to deal with honor at that time, together with the inquiries about mechanisms used to restore honor and its links with traditional masculinity. Theoretically, this work rescues contributions made by anthropologists and provides an overview of how honor and masculinity have been examined in the historiography. Starting from judicial records, the article considers the transversal character of honor in social terms and approaches its "double significance" as both a relational space for people and as a sphere for the confrontation of individuals.

  13. New trends in statistical physics festschrift in honor of Leopoldo Garcia-Colin's 80th birthday

    CERN Document Server

    Macias, Alfredo

    2010-01-01

    Prof Leopoldo Garcia-Colin will become 80 years old in 2010, therefore we are interested in the publication of a Festschrift (book) to honor him. Prof Garcia-Colin has worked in many different fields of statistical physics, and has applied it to biological physics, solid state physics, relativity and cosmology. We are planning a 500 pages book with original and peer-reviewed articles from his friends and former students. We may buy about 100 copies of it.

  14. Special Functions, Partial Differential Equations and Harmonic Analysis : Conference in Honor of Calixto P. Calderon

    CERN Document Server

    Stokolos, Alexander; Urbina, Wilfredo

    2014-01-01

    This volume of papers presented at the conference in honor of Calixto P. Calderón by his friends, colleagues, and students is intended to make the mathematical community aware of his important scholarly and research contributions in contemporary Harmonic Analysis and Mathematical Models applied to Biology and Medicine, and to stimulate further research in the future in this area of pure and applied mathematics.

  15. US Department of Energy High School Student Supercomputing Honors Program: A follow-up assessment

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    The US DOE High School Student Supercomputing Honors Program was designed to recognize high school students with superior skills in mathematics and computer science and to provide them with formal training and experience with advanced computer equipment. This document reports on the participants who attended the first such program, which was held at the National Magnetic Fusion Energy Computer Center at the Lawrence Livermore National Laboratory (LLNL) during August 1985.

  16. India’s British Army: the Honorable East India Company’s Lasting Military Impact

    Science.gov (United States)

    2017-06-09

    gaps which were as great or greater than that which American forces faced in 21st century Iraq and Afghanistan. Definitions and Terms The...between the Company’s model and that of American campaigns of the 21st century . While the employment of mercenaries was common during the Company’s era...18th, and 19th centuries by cultivating a privatized and indigenous military force there by way of the Honorable East India Company. In doing so

  17. Microscopic Gold Particle-Based Fiducial Markers for Proton Therapy of Prostate Cancer

    International Nuclear Information System (INIS)

    Lim, Young Kyung; Kwak, Jungwon; Kim, Dong Wook; Shin, Dongho; Yoon, Myonggeun; Park, Soah; Kim, Jin Sung; Ahn, Sung Hwan; Shin, Jungwook; Lee, Se Byeong; Park, Sung Yong; Pyo, Hong Ryeol; Kim, Dae Yong M.D.; Cho, Kwan Ho

    2009-01-01

    Purpose: We examined the feasibility of using fiducial markers composed of microscopic gold particles and human-compatible polymers as a means to overcome current problems with conventional macroscopic gold fiducial markers, such as dose reduction and artifact generation, in proton therapy for prostate cancer. Methods and Materials: We examined two types of gold particle fiducial marker interactions: that with diagnostic X-rays and with a therapeutic proton beam. That is, we qualitatively and quantitatively compared the radiographic visibility of conventional gold and gold particle fiducial markers and the CT artifacts and dose reduction associated with their use. Results: The gold particle fiducials could be easily distinguished from high-density structures, such as the pelvic bone, in diagnostic X-rays but were nearly transparent to a proton beam. The proton dose distribution was distorted <5% by the gold particle fiducials with a 4.9% normalized gold density; this was the case even in the worst configuration (i.e., parallel alignment with a single-direction proton beam). In addition, CT artifacts were dramatically reduced for the gold particle mixture. Conclusion: Mixtures of microscopic gold particles and human-compatible polymers have excellent potential as fiducial markers for proton therapy for prostate cancer. These include good radiographic visibility, low distortion of the depth-dose distribution, and few CT artifacts.

  18. Psychocultural Mechanisms of the Propensity toward Criminal Homicide: A Multidimensional View of the Culture of Honor

    Directory of Open Access Journals (Sweden)

    Monica G. T. C. Souza

    2017-11-01

    Full Text Available Introduction: Theory of the Culture of Honor is one of the few models in criminology specifically geared toward homicide. It proposes that, in certain societies, men must never show weakness and are required to react violently to any perceived threats to their reputation, thereby increasing their probability of committing a homicide. This has been suggested as the main explanation for the high rates of this type of crime in Brazil, particularly in the Northeast. Underlying this explanation there are complex mechanisms and processes that have yet to be clarified.Objectives: The present research aimed to investigate the workings of the possible psychocultural mechanisms underlying the culture of honor and the process through which they might affect the individual propensity toward homicide.Methods: A total of 336 Brazilian adults were assessed regarding a broad range of sociodemographic, psychological, and sociocultural variables, including their attitudes toward homicide. The resulting dataset was analyzed using Smallest Space Analysis and Facet Theory.Results: It seems that certain cultural elements associated to traditional masculinity and enhanced anger tend to promote negative personality traits and increase one’s propensity toward committing homicide.Conclusion: The findings obtained not only confirm the Theory of the Culture of Honor for the propensity toward homicide, but also explicit and clarify some of the psychocultural processes and mechanisms involved, suggesting a new scientific framework.

  19. Psychocultural Mechanisms of the Propensity toward Criminal Homicide: A Multidimensional View of the Culture of Honor

    Science.gov (United States)

    Souza, Monica G. T. C.; Souza, Bruno C.; Roazzi, Antonio; da Silva, Edson S.

    2017-01-01

    Introduction: Theory of the Culture of Honor is one of the few models in criminology specifically geared toward homicide. It proposes that, in certain societies, men must never show weakness and are required to react violently to any perceived threats to their reputation, thereby increasing their probability of committing a homicide. This has been suggested as the main explanation for the high rates of this type of crime in Brazil, particularly in the Northeast. Underlying this explanation there are complex mechanisms and processes that have yet to be clarified. Objectives: The present research aimed to investigate the workings of the possible psychocultural mechanisms underlying the culture of honor and the process through which they might affect the individual propensity toward homicide. Methods: A total of 336 Brazilian adults were assessed regarding a broad range of sociodemographic, psychological, and sociocultural variables, including their attitudes toward homicide. The resulting dataset was analyzed using Smallest Space Analysis and Facet Theory. Results: It seems that certain cultural elements associated to traditional masculinity and enhanced anger tend to promote negative personality traits and increase one’s propensity toward committing homicide. Conclusion: The findings obtained not only confirm the Theory of the Culture of Honor for the propensity toward homicide, but also explicit and clarify some of the psychocultural processes and mechanisms involved, suggesting a new scientific framework. PMID:29163264

  20. An innovative immunosensor for ultrasensitive detection of breast cancer specific carbohydrate (CA 15-3) in unprocessed human plasma and MCF-7 breast cancer cell lysates using gold nanospear electrochemically assembled onto thiolated graphene quantum dots.

    Science.gov (United States)

    Hasanzadeh, Mohammad; Tagi, Solmaz; Solhi, Elham; Mokhtarzadeh, Ahad; Shadjou, Nasrin; Eftekhari, Aziz; Mahboob, Soltanali

    2018-04-03

    The accurate quantification of the level of breast cancer specific protein CA 15-3 in serum is crucial for cancer prognosis. This work, a novel and sensitive label-free immunoassay based on gold nanospear (Au NSs) electrochemically assembled onto thiolated graphene quantum dots (CysA/GQDs) for the detection of CA 15-3 antibodies. The CysA/Au NSs/GQDs hybrid interface provides a large surface area for the effective immobilization of CA 15-3 antigens, as well as it ascertains the bioactivity and stability of immobilized CA 15-3 antigens. Field emission scanning electron microscope (FE-SEM), and EDS photoelectron spectroscopies were used to monitor the sensor fabrication. Also, cyclic voltammetry was used to quantify the extent of Au NSs' surface coverage by CA 15-3 antigens. Square wave voltammetry (SWV) was employed to investigate the immunosensor fabrication and to monitor the binding events between CA 15-3 antigens-antibodies. Under optimized experimental conditions, the immunosensor displayed good sensitivity and specificity. The CA 15-3 were detected in a concentration as low as 0.11U/mL with a linear range from 0.16-125U/mL. The high sensitivity of the immunosensor may derive from the high loading of CA 15-3 antibodies on CysA/Au NSs/GQDs hybrid interface which increases the number of binding events. The method was successfully applied assay of the CA 15-3 in unprocessed human plasma samples. Also, proposed immunosensor was applied to the assay of CA 15-3 malignant cell line lysates (human breast adenocarcinoma cell line-MCF-7). Copyright © 2018. Published by Elsevier B.V.

  1. Gold nanoparticle core-europium(iii) chelate fluorophore-doped silica shell hybrid nanocomposites for the lateral flow immunoassay of human thyroid stimulating hormone with a dual signal readout.

    Science.gov (United States)

    Preechakasedkit, Pattarachaya; Osada, Kota; Katayama, Yuta; Ruecha, Nipapan; Suzuki, Koji; Chailapakul, Orawon; Citterio, Daniel

    2018-01-21

    Hybrid nanocomposite particles composed of a gold core coated with a europium(iii)-chelate fluorophore-doped silica shell (AuNPs@SiO 2 -Eu 3+ ) have been synthesized and applied as antibody labels in lateral flow immunoassay (LFIA) devices for the determination of human thyroid stimulating hormone (hTSH). Labeling of monoclonal anti-hTSH antibodies with AuNPs@SiO 2 -Eu 3+ nanocomposites allows for both colorimetric and fluorometric observation of assay results on LFIA devices, relying on visible light absorption due to the localized surface plasmon resonance of the Au-core and the fluorescence emission of the Eu(iii)-chelate-modified shell under UV hand lamp irradiation (365 nm), respectively. The possibility for a dual signal readout provides an attractive alternative for LFIAs: instantaneous naked eye observation of the AuNP colorimetric signal as in conventional LFIAs for hypothyroidism detection, and more sensitive fluorescence detection to assess hyperthyroidism. The limits of detection (LOD) for naked eye observation of LFIA devices are 5 μIU mL -1 and 0.1 μIU mL -1 for the colorimetric and fluorimetric detection, respectively. Using the fluorescence detection scheme in combination with a smartphone and digital color analysis, a quantitative linear relationship between the red intensity and the logarithmic concentration of hTSH was observed (R 2 = 0.988) with an LOD of 0.02 μIU mL -1 . Finally, LFIA devices were effectively applied for detecting hTSH in spiked diluted human serum with recovery values between 100-116%.

  2. Activation analysis in gold industry

    International Nuclear Information System (INIS)

    Kist, A. A.

    2003-01-01

    Nuclear techniques and methods were, are, and will be very important for many fields of science, agriculture, industry, etc. Among other examples one can remember role of the nuclear medicine (radiotherapy and radiodiagnostic methods) or semiconductors (communication, computing, information, etc.) which industrial production has been on initial stage based on activation analysis. One of very illustrative examples is application of nuclear methods in gold industry. This is given by favorable nuclear properties of gold. Uzbekistan is one of the main producers of gold. Open-cast mining and hydro metallurgic extraction (using leaching by cyanide and sorption by ion-exchange resin) is the mostly used technology. The typical gold ores are sulfide and contain elevated concentration of As and Sb. That needs special technology of gold extraction. Importance of gold for Uzbekistan economy is a reason why for many years there are carried out studies concerning to gold production. These studies include also nuclear methods and their results are successfully used in gold industry. The present paper gives a brief overview for period of 25 years. For many reasons most of these studies were not published before completely. Despite some results are obtained decades ago we decided to present the overview as an example how nuclear methods can cover requirements of the whole process. We are trying to sort these studies according to methods and applications

  3. Marrying Sciences and the Humanities: A New Approach to Teaching Western Civilization.

    Science.gov (United States)

    Dick, B. Gale

    1989-01-01

    The University of Utah offers an interdisciplinary, historically oriented humanities-science course, a modification and extension of the traditional Western Civilization course, in its honors program. The course has been successful for 12 years. (MSE)

  4. Stealing the Gold

    International Nuclear Information System (INIS)

    Whittington, S G

    2005-01-01

    Stealing the Gold presents a survey of some of the most exciting topics in condensed matter physics today, from the perspective of the pioneering work of Sam Edwards. Original articles from leaders in the field, including several Nobel laureates, highlight the historical development as well as new and emerging areas. This book would be of interest to graduate students and researchers in condensed matter physics, statistical physics and theoretical physics. Over the course of nearly half a century, Sam Edwards has led the field of condensed matter physics in new directions, ranging from the electronic and statistical properties of disordered materials to the mechanical properties of granular materials. Along the way he has provided seminal contributions to fluid mechanics, polymer science, surface science and statistical mechanics. This volume celebrates the immense scope of his influence by presenting a collection of original articles by recognized leaders in theoretical physics, including two Nobel laureates and a Fields medalist, which describe the genesis, evolution and future prospects of the various sub-fields of condensed matter theory, along with reprints of a selection of Edwards' seminal papers that helped give birth to the subject. Stealing the Gold, Edwards' favourite caricature of the relationship between theoretical physicists and nature, will be of singular interest to graduate students looking for an overview of some of the most exciting areas of theoretical physics, as well as to researchers in condensed matter physics looking for a comprehensive, broad and uniquely incisive snapshot of their subject at the dawn of the 21st century. (book review)

  5. The Humanities Are Dead! Long Live the Humanities!

    Science.gov (United States)

    Andrews, Larry

    2015-01-01

    The academic disciplines and values of the humanities in western cultures run from the Greek trivium--grammar, logic, rhetoric--to modern-day studies in history, philosophy, religious studies, literature, languages, art history, and some interdisciplinary studies. What is their future, and what is their relationship to honors education? Are the…

  6. Shape evolution of gold nanoparticles

    International Nuclear Information System (INIS)

    Wang, Y. Q.; Liang, W. S.; Geng, C. Y.

    2010-01-01

    The tetraoctylammonium bromide-stabilized gold nanoparticles have been successfully fabricated. The shape evolution of these nanoparticles under different annealing temperatures has been investigated using high-resolution transmission electron microscopy. After an annealing at 100 o C for 30 min, the average diameters of the gold nanoparticles change a little. However, the shapes of gold nanoparticles change drastically, and facets appear in most nanoparticles. After an annealing at 200 o C for 30 min, not only the size but also the shape changes a lot. After an annealing at 300 o C for 30 min, two or more gold nanoparticles coalesce into bigger ones. In addition, because of the presence of Cu grid during the annealing, some gold particles become the nucleation sites of Cu 2 O nanocubes, which possess a microstructure of gold-particle core/Cu 2 O shell. These Au/Cu 2 O heterostructure nanocubes can only be formed at a relatively high temperature (≥300 o C). The results can provide some insights on controlling the shapes of gold nanoparticles.

  7. THE CYANIDE LEACH TECHNOLOGY IN GOLD AND SILVER MINING HARMFUL EFFECTS AND SUGGESTIONS FOR REMEDYING

    Directory of Open Access Journals (Sweden)

    Judit PETRES

    2013-11-01

    Full Text Available The region named Roşia Montană became famous due to its rich mineral resources. The most precious treasure which has been found is the gold. A state-run gold mine functioned for many years and the continuous pollution due to the gold extraction became very dangerous. All these cyanide-containing waste are hazardous to wildlife, natural resources and human health if not properly managed. The consequences of cyanide hazards may be devastating, sometimes killing everything for several miles downstream. It has not yet been found a way of both taking advantages of the economic benefits of gold and maintaining a liveable habitat.

  8. The Strengthening of Geological Infrastructure, Research and Data Acquisition - Using Gis in Ivory Coast Gold Mines

    Directory of Open Access Journals (Sweden)

    Kouame Kouame Joseph Arthur

    2017-01-01

    Full Text Available The artisanal gold mining in Ivory Coast has become a key problem in the mining sector. A diverse group of people in Ivory Coast, including the young and the old, are all engaged in these activities that are reportedly better than agricultural inputs. However, it is still a high-risk activity that leads to pollution, environmental degradation and the loss of human life. About ten people die each year in the gold mines. This paper focuses on gold mine safety by using the Geographic Information System (GIS as a major solution to solve the artisanal gold mines problem, and also seeks to promote the mining industry in Ivory Coast.

  9. Microbial biosynthesis of nontoxic gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Swarup, E-mail: swaruproy@klyuniv.ac.in [Department of Biochemistry and Biophysics, University of Kalyani, Kalyani 741235, West Bengal (India); Das, Tapan Kumar [Department of Biochemistry and Biophysics, University of Kalyani, Kalyani 741235, West Bengal (India); Maiti, Guru Prasad [Department of Molecular Biology and Biotechnology, University of Kalyani, Kalyani 741235, West Bengal (India); Department of Anesthesiology, Texas Tech University Health science Center, 3601 4th Street, Lubbock, TX 79430 (United States); Basu, Utpal [Department of Molecular Biology and Biotechnology, University of Kalyani, Kalyani 741235, West Bengal (India)

    2016-01-15

    Graphical abstract: The manuscript deals with the fungus mediated optimized biologically synthesized GNPs using Aspergillus foetidus and characterization of biosynthesized GNPs using various physico-chemical methods. The fairly stable synthesized nanoparticles have size in the range of 10–40 nm. Cytotoxicity study of biosynthesized GNPs on Human lung cancer cell line A549 showed no significant toxicity of GNPs. - Highlights: • A novel biosynthesis process of GNPs using Aspergillus foetidus. • Biosynthesized GNPs are in the range of 10–40 nm as observed from TEM. • This process of synthesis is an optimized biosynthesis process of GNPs. • Biosynthesized GNPs are noncytotoxic against A549 cell line. - Abstract: We study the extracellular biosynthesis of gold nanoparticles (GNPs) using the fungal species Aspergillus foetidus. The formation of GNPs were initially monitored by visual observation and then characterized with the help of various characterization techniques. X-ray diffraction (XRD) results revealed distinctive formation of face centered cubic crystalline GNPs. From field emission scanning electron microscopy (FESEM) the morphology of the nanoparticles were found to be roughly spherical and within the size range of 30–50 nm. The spherical and polydispersed GNPs in the range of 10–40 nm were observed by transmission electron microscopy (TEM) analysis. It was established that alkaline pH, 1 mM gold salt concentration and 75 °C temperature were the respective optimum parameter for biosynthesis of GNPs. Cell cytotoxicity of GNP was compared with that of normal gold salt solution on A549 cell. The A549 cell growth in presence of GNPs was found to be comparatively less toxic than the gold ion.

  10. Microbial biosynthesis of nontoxic gold nanoparticles

    International Nuclear Information System (INIS)

    Roy, Swarup; Das, Tapan Kumar; Maiti, Guru Prasad; Basu, Utpal

    2016-01-01

    Graphical abstract: The manuscript deals with the fungus mediated optimized biologically synthesized GNPs using Aspergillus foetidus and characterization of biosynthesized GNPs using various physico-chemical methods. The fairly stable synthesized nanoparticles have size in the range of 10–40 nm. Cytotoxicity study of biosynthesized GNPs on Human lung cancer cell line A549 showed no significant toxicity of GNPs. - Highlights: • A novel biosynthesis process of GNPs using Aspergillus foetidus. • Biosynthesized GNPs are in the range of 10–40 nm as observed from TEM. • This process of synthesis is an optimized biosynthesis process of GNPs. • Biosynthesized GNPs are noncytotoxic against A549 cell line. - Abstract: We study the extracellular biosynthesis of gold nanoparticles (GNPs) using the fungal species Aspergillus foetidus. The formation of GNPs were initially monitored by visual observation and then characterized with the help of various characterization techniques. X-ray diffraction (XRD) results revealed distinctive formation of face centered cubic crystalline GNPs. From field emission scanning electron microscopy (FESEM) the morphology of the nanoparticles were found to be roughly spherical and within the size range of 30–50 nm. The spherical and polydispersed GNPs in the range of 10–40 nm were observed by transmission electron microscopy (TEM) analysis. It was established that alkaline pH, 1 mM gold salt concentration and 75 °C temperature were the respective optimum parameter for biosynthesis of GNPs. Cell cytotoxicity of GNP was compared with that of normal gold salt solution on A549 cell. The A549 cell growth in presence of GNPs was found to be comparatively less toxic than the gold ion.

  11. Directed Assembly of Gold Nanoparticles

    DEFF Research Database (Denmark)

    Westerlund, Axel Rune Fredrik; Bjørnholm, Thomas

    2009-01-01

    As a complement to common "top-down" lithography techniques, "bottom-up" assembly techniques are emerging as promising tools to build nanoscale structures in a predictable way. Gold nanoparticles that are stable and relatively easy to synthesize are important building blocks in many such structures...... due to their useful optical and electronic properties. Programmed assembly of gold nanoparticles in one, two, and three dimensions is therefore of large interest. This review focuses on the progress from the last three years in the field of directed gold nanoparticle and nanorod assembly using...

  12. GOLD and the fixed ratio

    Directory of Open Access Journals (Sweden)

    Vestbo J

    2012-09-01

    Full Text Available Jørgen VestboUniversity of Manchester, Manchester, UKI read with interest the paper entitled "Diagnosis of airway obstruction in the elderly: contribution of the SARA study" by Sorino et al in a recent issue of this journal.1 Being involved in the Global Initiative for Obstructive Lung Diseases (GOLD, it is nice to see the interest sparked by the GOLD strategy document. However, in the paper by Sorino et al, there are a few misunderstandings around GOLD and the fixed ratio (forced expiratory volume in 1 second/forced volume vital capacity < 0.70 that need clarification.View original paper by Sorino and colleagues.

  13. Fabrication, nanomechanical characterization, and cytocompatibility of gold-reinforced chitosan bio-nanocomposites

    International Nuclear Information System (INIS)

    Patel, Nimitt G.; Kumar, Ajeet; Jayawardana, Veroni N.; Woodworth, Craig D.; Yuya, Philip A.

    2014-01-01

    Chitosan, a naturally derived polymer represents one of the most technologically important classes of active materials with applications in a variety of industrial and biomedical fields. Gold nanoparticles (∼ 32 nm) were synthesized via a citrate reduction method from chloroauric acid and incorporated in Chitosan matrix. Bio-nanocomposite films with varying concentrations of gold nanoparticles were prepared through solution casting process. Uniform distribution of gold nanoparticles was achieved throughout the chitosan matrix and was confirmed with SEM. Synthesis outcomes and prepared nanocomposites were characterized using SEM, TEM, EDX, SAED, UV–vis, XRD, DLS, and Zeta potential for their physical, morphological and structural properties. Nanoscale properties of materials under the influence of temperature were characterized through nanoindentation techniques. From quasi-static nanoindentation, it was observed that hardness and reduced modulus of the nanocomposites were increased significantly in direct proportion to the gold nanoparticle concentration. Gold nanoparticle concentration also showed positive impact on storage modulus and thermal stability of the material. The obtained films were confirmed to be biocompatible by their ability to support growth of human cells in vitro. In summary, the results show enhanced mechanical properties with increasing gold nanoparticle concentration, and provide better understanding of the structure–property relationships of such biocompatible materials for potential biomedical applications. - Highlights: • We fabricated gold reinforced chitosan nanocomposite for biomedical applications. • Gold nanoparticles significantly enhanced nanomechanical properties of chitosan. • Nanocomposite films supported growth of human cells in vitro. • Gold nanoparticles significantly improved cell proliferation on chitosan films

  14. Grafting of Gold Nanoparticles on Glass Using Sputtered Gold Interlayers

    OpenAIRE

    Kvítek, Ondřej; Hendrych, Robin; Kolská, Zdeňka; Švorčík, Václav

    2014-01-01

    Three-step preparation of nanostructured Au layer on glass substrate is described. The procedure starts with sputtered gold interlayer, followed by grafting with dithiols and final coverage with gold nanoparticles (AuNPs). Successful binding of dithiols on the sputtered Au film was confirmed by X-ray photoelectron spectroscopy measurement. AuNPs bound to the surface were observed using atomic force microscopy. Both single nanoparticles and their aggregates were observed. UV-Vis spectra show b...

  15. 41 CFR 101-45.002 - Gold.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Gold. 101-45.002 Section... PERSONAL PROPERTY § 101-45.002 Gold. (a) Gold will be sold in accordance with this section and part 102-38 of the Federal Management Regulation. (b) Sales of gold shall be processed to— (1) Use the sealed bid...

  16. ESO Receives Computerworld Honors Program 21st Century Achievement Award in Science Category

    Science.gov (United States)

    2005-06-01

    In a ceremony held in Washington, D.C. (USA) on June 6, 2005, ESO, the European Organisation for Astronomical Research in the southern Hemisphere, received the coveted 21st Century Achievement Award from the Computerworld Honors Program for its visionary use of information technology in the Science category. Sybase, a main database server vendor and member of the Chairmen's Committee, nominated ESO's Data Flow System in recognition of its contributions to the global information technology revolution and its positive impact on society. The citations reads: "ESO has revolutionized the operations of ground-based astronomical observatories with a new end-to-end data flow system, designed to improve the transmission and management of astronomical observations and data over transcontinental distances." This year's awards, in 10 categories, were presented at a gala event at the National Building Museum, attended by over 250 guests, including leaders of the information technology industry, former award recipients, judges, scholars, and diplomats representing many of the 54 countries from which the 17-year-old program's laureates have come. "The Computerworld Honors Program 21st Century Achievement Awards are presented to companies from around the world whose visionary use of information technology promotes positive social, economic and educational change," said Bob Carrigan, president and CEO of Computerworld and chairman of the Chairmen's Committee of the Computerworld Honors Program. "The recipients of these awards are the true heroes of the information age and have been appropriately recognized by the leading IT industry chairmen as true revolutionaries in their fields." ESO PR Photo 18/05 ESO PR Photo 18/05 ESO Receives the Award in the Science Category [Preview - JPEG: 400 x 496 pix - 53k] [Normal - JPEG: 800 x 992 pix - 470k] [Full Res - JPEG: 1250 x 1550 pix - 1.1M] Caption: ESO PR Photo 18/05: Receiving the Computerworld 21st Century Achievement Award for Science

  17. Size fraction assaying of gold bearing rocks (for gold extraction) by ...

    African Journals Online (AJOL)

    A novel method has been developed for processing and extraction of gold from gold bearing rocks for use by small-scale gold miners in Ghana. The methodology involved crushing of gold bearing hard rocks to fine particles to form a composite sample and screening at a range of sizes. Gold distribution in the composite ...

  18. Determinantes dos Honorários de Auditoria: um Estudo nas Empresas Listadas na BM&FBOVESPA, Brasil

    Directory of Open Access Journals (Sweden)

    Walther Bottaro de Lima Castro

    2015-12-01

    Full Text Available RESUMO Este trabalho analisa os determinantes dos honorários de auditoria pagos por empresas listadas na BM&FBOVESPA. Os dados referentes às empresas listadas para 2012 mostram relação positiva entre honorários com as variáveis porte, complexidade do cliente e auditores Big N. O risco percebido pelo auditor demonstrou afetar os valores dos honorários de forma diferente nos clientes de maior e menor porte. Nos de menor porte, os resultados sugerem que o auditor cobre menores honorários de clientes mais alavancados e com maior risco, contrariando a hipótese de que o auditor cobraria maiores honorários como prêmio pelo risco assumido. Já nos de maior porte, os resultados demonstram que clientes com maior risco, medido pela liquidez e alavancagem, ou com maiores práticas de governança, tendem a gastar mais com auditoria. Quanto à troca do auditor, os resultados apontaram que clientes maiores pagam menos no primeiro ano de auditoria. Esses resultados qualificam os achados de Hallak e Silva (2012, sugerindo a necessidade de novas pesquisas com bases temporalmente mais extensas.

  19. Optical trapping of gold aerosols

    DEFF Research Database (Denmark)

    Schmitt, Regina K.; Pedersen, Liselotte Jauffred; Taheri, S. M.

    2015-01-01

    Aerosol trapping has proven challenging and was only recently demonstrated.1 This was accomplished by utilizing an air chamber designed to have a minimum of turbulence and a laser beam with a minimum of aberration. Individual gold nano-particles with diameters between 80 nm and 200 nm were trapped...... in air using a 1064 nm laser. The positions visited by the trapped gold nano-particle were quantified using a quadrant photo diode placed in the back focal plane. The time traces were analyzed and the trapping stiffness characterizing gold aerosol trapping determined and compared to aerosol trapping...... of nanometer sized silica and polystyrene particles. Based on our analysis, we concluded that gold nano-particles trap more strongly in air than similarly sized polystyrene and silica particles. We found that, in a certain power range, the trapping strength of polystyrene particles is linearly decreasing...

  20. Gold, currencies and market efficiency

    Science.gov (United States)

    Kristoufek, Ladislav; Vosvrda, Miloslav

    2016-05-01

    Gold and currency markets form a unique pair with specific interactions and dynamics. We focus on the efficiency ranking of gold markets with respect to the currency of purchase. By utilizing the Efficiency Index (EI) based on fractal dimension, approximate entropy and long-term memory on a wide portfolio of 142 gold price series for different currencies, we construct the efficiency ranking based on the extended EI methodology we provide. Rather unexpected results are uncovered as the gold prices in major currencies lay among the least efficient ones whereas very minor currencies are among the most efficient ones. We argue that such counterintuitive results can be partly attributed to a unique period of examination (2011-2014) characteristic by quantitative easing and rather unorthodox monetary policies together with the investigated illegal collusion of major foreign exchange market participants, as well as some other factors discussed in some detail.

  1. Gold based bulk metallic glass

    Science.gov (United States)

    Schroers, Jan; Lohwongwatana, Boonrat; Johnson, William L.; Peker, Atakan

    2005-08-01

    Gold-based bulk metallic glass alloys based on Au-Cu-Si are introduced. The alloys exhibit a gold content comparable to 18-karat gold. They show very low liquidus temperature, large supercooled liquid region, and good processibility. The maximum casting thickness exceeds 5mm in the best glassformer. Au49Ag5.5Pd2.3Cu26.9Si16.3 has a liquidus temperature of 644K, a glass transition temperature of 401K, and a supercooled liquid region of 58K. The Vickers hardness of the alloys in this system is ˜350Hv, twice that of conventional 18-karat crystalline gold alloys. This combination of properties makes the alloys attractive for many applications including electronic, medical, dental, surface coating, and jewelry.

  2. Biomass processing over gold catalysts

    CERN Document Server

    Simakova, Olga A; Murzin, Dmitry Yu

    2014-01-01

    The book describes the valorization of biomass-derived compounds over gold catalysts. Since biomass is a rich renewable feedstock for diverse platform molecules, including those currently derived from petroleum, the interest in various transformation routes has become intense. Catalytic conversion of biomass is one of the main approaches to improving the economic viability of biorefineries.  In addition, Gold catalysts were found to have outstanding activity and selectivity in many key reactions. This book collects information about transformations of the most promising and important compounds derived from cellulose, hemicelluloses, and woody biomass extractives. Since gold catalysts possess high stability under oxidative conditions, selective oxidation reactions were discussed more thoroughly than other critical reactions such as partial hydrogenation, acetalization, and isomerization. The influence of reaction conditions, the role of the catalyst, and the advantages and disadvantages of using gold are pre...

  3. Risk and reliability analysis theory and applications : in honor of Prof. Armen Der Kiureghian

    CERN Document Server

    2017-01-01

    This book presents a unique collection of contributions from some of the foremost scholars in the field of risk and reliability analysis. Combining the most advanced analysis techniques with practical applications, it is one of the most comprehensive and up-to-date books available on risk-based engineering. All the fundamental concepts needed to conduct risk and reliability assessments are covered in detail, providing readers with a sound understanding of the field and making the book a powerful tool for students and researchers alike. This book was prepared in honor of Professor Armen Der Kiureghian, one of the fathers of modern risk and reliability analysis.

  4. Theoretical chemistry theory of scattering papers in honor of Henry Eyring

    CERN Document Server

    Henderson, Douglas W

    1981-01-01

    Theoretical Chemistry: Theory of Scattering: Papers in Honor of Henry Eyring, Volume 6, Part A covers the aspects of reactive and nonreactive scattering. The book discusses the applications of classical trajectory to reactive scattering and the accurate quantum calculations of reactive systems. The text also describes the fluctuations in chemically reacting systems, as well as the coupling of electronically adiabatic states in atomic and molecular collisions. Chemists, physicists, people involved in the study of the theory of scattering, and students taking related courses will find the book u

  5. A Reassessment of the Concept of Honor in the Spanish Theater of the Golden Age

    Directory of Open Access Journals (Sweden)

    A. Robert Lauer

    2017-05-01

    Full Text Available reassessed taking into consideration anthropological, civil, legal, lexical, moral, philosophical, theological and psychological aspects. An application of this refurbished concept follows, wherein the idea of honor as a social concept and as a moral attribute clash in three villein plays: Pedro Calderón de la Barca’s The Mayor of Zalamea (El alcalde de Zalamea and Lope de Vega’s All Citizens Are Soldiers (Fuenteovejuna, and Peribáñez and the Comendador of Ocaña (Peribáñez y el Comendador de Ocaña.

  6. Del concepto a la forma: la dualidad en Amor, honor y poder

    OpenAIRE

    Vara López, Alicia

    2011-01-01

    La finalidad fundamental de esta comunicación es demostrar que Amor, honor y poder es una comedia muy representativa del conceptismo en verso teatral del primer Calderón, por responder a un patrón constructivo marcado por el principio de dualidad. Es evidente la existencia de dualidades y simetrías en toda la obra del autor, pero en este caso existe una correspondencia muy marcada entre los contrastes que aparecen en el ámbito del contenido y aquellos que atañen a la forma. Est...

  7. Gold nanorod vaccine for respiratory syncytial virus

    International Nuclear Information System (INIS)

    Stone, John W; Thornburg, Natalie J; Blum, David L; Kuhn, Sam J; Crowe Jr, James E; Wright, David W

    2013-01-01

    Respiratory syncytial virus (RSV) is a major cause of pneumonia and wheezing in infants and the elderly, but to date there is no licensed vaccine. We developed a gold nanorod construct that displayed the major protective antigen of the virus, the fusion protein (F). Nanorods conjugated to RSV F were formulated as a candidate vaccine preparation by covalent attachment of viral protein using a layer-by-layer approach. In vitro studies using ELISA, electron microscopy and circular dichroism revealed that conformation-dependent epitopes were maintained during conjugation, and transmission electron microscopy studies showed that a dispersed population of particles could be achieved. Human dendritic cells treated with the vaccine induced immune responses in primary human T cells. These results suggest that this vaccine approach may be a potent method for immunizing against viruses such as RSV with surface glycoproteins that are targets for the human immune response. (paper)

  8. Immunological properties of gold nanoparticles

    OpenAIRE

    Dykman, Lev A.; Khlebtsov, Nikolai G.

    2016-01-01

    In the past decade, gold nanoparticles have attracted strong interest from the nanobiotechnological community owing to the significant progress made in robust and easy-to-make synthesis technologies, in surface functionalization, and in promising biomedical applications. These include bioimaging, gene diagnostics, analytical sensing, photothermal treatment of tumors, and targeted delivery of various biomolecular and chemical cargos. For the last-named application, gold nanoparticles should be...

  9. Goldenphilicity: Luminescent gold compounds

    International Nuclear Information System (INIS)

    Sansores, L.E.

    2002-01-01

    In the solids and molecules different types of bonds are presented depending on the involved atoms, covalent bonds are common among elements of open shell, where more bond orbitals are filled than anti bond orbitals. It is expected that ionic bonds among closed shell atoms which have charges of opposite sign. Bonds type Van der Waals are presented among molecules which have a bipolar moment. It would not be expected bonds among zero charge species, or more generally with the same nominal charge and in any case the attractive forces would be very small. In fact it is expected that two metallic cations to be repelled each other. There recently is evidence that in organic or organometallic compounds could exist attractive interactions between two cations of the d 8 -d 10 -s 2 families. These bonds are weak but stronger than those of Van der Waals. They are compared with the hydrogen bonds. In this work it was reviewed some examples in which the goldenphilicity plays an important role in the luminescence that the gold complexes present. Examples of mono, bi and trinuclear and the structures that these organometallic compounds could take are examined. (Author)

  10. Gold nanoparticle-based microfluidic sensor for mercury detection

    DEFF Research Database (Denmark)

    Lafleur, Josiane P.; Jensen, Thomas Glasdam; Kutter, Jörg Peter

    2011-01-01

    The contamination of natural resources by human activity can have severe socio-economical impacts. Conventional methods of environmental analysis can be significantly improved by the development of portable microscale technologies for remote/field sensing. A gold nanoparticle-based lab-on-a-chip ...

  11. Effects of artisanal small-scale gold mining on fisheries ...

    African Journals Online (AJOL)

    Artisanal Small-scale Gold Mining (ASGM) has direct and indirect impacts on fisheries management. These impacts are mainly about the quality of the water where fish lives, ownership of the surrounding waters, land and human health. This study was carried out in two landing sites of Wagusu and Riskis Kogwari in ...

  12. Targeting dendritic cells through gold nanoparticles: A review on the cellular uptake and subsequent immunological properties.

    Science.gov (United States)

    Ahmad, Suhana; Zamry, Anes Ateqah; Tan, Hern-Tze Tina; Wong, Kah Keng; Lim, JitKang; Mohamud, Rohimah

    2017-11-01

    Gold nanoparticles (NPs) have been proposed as a highly potential tool in immunotherapies due to its advantageous properties including customizable size and shapes, surface functionality and biocompatibility. Dendritic cells (DCs), the sentinels of immune response, have been of interest to be manipulated by using gold NPs for targeted delivery of immunotherapeutic agent. Researches done especially in human DCs showed a variation of gold NPs effects on cellular uptake and internalization, DC maturation and subsequent T cells priming as well as cytotoxicity. In this review, we describe the synthesis and physiochemical properties of gold NPs as well as the importance of gold NPs in immunotherapies through their actions on human DCs. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. The concept of «honor», «dignity» in the context of the professionalization of public service

    Directory of Open Access Journals (Sweden)

    S. M. Serjogin

    2016-09-01

    Full Text Available The article analyzes ethical aspects of the personality of a public servant. Such  concepts as, «professional honor», «professional dignity», «professional justice», «professional responsibility» are disclosed. The role of these concepts in public servants’ professional activities is defermined. It is stated that professional dignity of the public servant is closely connected with his position in the team, his personal merit and honor public servant. The matter is that a public servant is a representative a particular team, and the entire public service. The attention is focused on the fact that the higher developed feeling of personal and official dignity of public servants, the more he values his professional honor, the more significant social value he has to society. As a result, professional honor and professional dignity, complement each other, help to maintain a certain, fairly high level of a public servant’s morality. It was found that such concepts as «professional honor», «professional dignity», «professional justice», «professional responsibility» were brought up before and are brought up now in a large stable structures and organizations of the world. In developed countries, such as France, Germany, Japan, England – the honor and responsibility of public servant are essential professional qualities, which largely determine style of activities and influence decision-making process. In our country, nowadays, the education of a public servant is missed, therefore we will not be able in the future to count on the loyalty of civil servants to their job. We will have to deal with the satisfaction of public servants’ personal needs, as it often happens now. Based on the analysis concluded that the professional ethics of a public servant is a rather complicated and weighty task of harmonizing professional and personal moral responsibility, principles, values and interests.

  14. Honoring Choices Minnesota: preliminary data from a community-wide advance care planning model.

    Science.gov (United States)

    Wilson, Kent S; Kottke, Thomas E; Schettle, Sue

    2014-12-01

    Advance care planning (ACP) increases the likelihood that individuals who are dying receive the care that they prefer. It also reduces depression and anxiety in family members and increases family satisfaction with the process of care. Honoring Choices Minnesota is an ACP program based on the Respecting Choices model of La Crosse, Wisconsin. The objective of this report is to describe the process, which began in 2008, of implementing Honoring Choices Minnesota in a large, diverse metropolitan area. All eight large healthcare systems in the metropolitan area agreed to participate in the project, and as of April 30, 2013, the proportion of hospitalized individuals 65 and older with advance care directives in the electronic medical record was 12.1% to 65.6%. The proportion of outpatients aged 65 and older was 11.6% to 31.7%. Organizations that had sponsored recruitment initiatives had the highest proportions of records containing healthcare directives. It was concluded that it is possible to reduce redundancy by recruiting all healthcare systems in a metropolitan area to endorse the same ACP model, although significantly increasing the proportion of individuals with a healthcare directive in their medical record requires a campaign with recruitment of organizations and individuals. © 2014 The Authors.The Journal of the American Geriatrics Society published by Wiley Periodicals, Inc. on behalf of The American Geriatrics Society.

  15. Preparing Students for Global Citizenship: The Effects of a Dutch Undergraduate Honors Course

    Directory of Open Access Journals (Sweden)

    Ingrid W. Schutte

    2017-01-01

    Full Text Available Using a mixed method approach, this case study investigates effects on the participating students (N=25 of an undergraduate honors course in the Netherlands, aimed at global justice citizenship. Knowledge about effects of global citizenship courses is still limited. The Ethical Sensitivity Scale Questionnaire and the Global Citizenship Scale were used in a pre- and posttest design to measure possible development in the moral and civic domain among the participants of the course. In the qualitative part, deductive content analyses of students’ work and students’ written reflection on the course, utilizing the theory-based curriculum guidelines Global Justice Citizenship Education, were performed. In addition, a follow-up blog and interview were analyzed to learn students’ perception on the effects of the course after half a year. Quantitative results show increased ethical sensitivity as well as global civic engagement and global competence among the participants. Qualitative results point in the same direction and provide deeper insights in the content of students’ learning and the perceived impact of the course on their attitudes and behavior. Results are discussed in relation to theory on justice-oriented global citizenship and honors pedagogies.

  16. Pudor, honor, and autoridad: the evolving patient-physician relationship in Spain.

    Science.gov (United States)

    Epstein, R M; Borrell i Carrió, F

    2001-10-01

    The expression of emotion and the sharing of information are determined by cultural factors, consultation time, and the structure of the health care system. Two emblematic situations in Spain - the expression of aggression in the patient-physician encounter, and the withholding of diagnostic information from the patient - have not been well-described in their sociocultural context. To explore these, the authors observed and participated in clinical practice and teaching in several settings throughout Spain and analyzed field notes using qualitative methods. In this paper, we explore three central constructs - modesty (pudor), dignity (honor), and authority (autoridad) - and their expressions in patient-physician encounters. We define two types of emotions in clinical settings - public, extroverted expressions of anger and exuberance; and private, deeply held feelings of fear and grief that tend to be expressed through the arts and religion. Premature reassurance and withholding of information are interpreted as attempts to reconstruct the honor and pudor of the patient. Physician authority and perceived loyalty to the government-run health care system generate conflict and aggression in the patient-physician relationship. These clinical behaviors are contextualized within cultural definitions of effective communication, an ideal patient-physician relationship, the role of the family, and ethical behavior. Despite agreement on the goals of medicine, the behavioral manifestations of empathy and caring in Spain contrast substantially with northern European and North American cultures.

  17. "A riesgo de perder el honor". Transgresiones sexuales de las mujeres en Quetzaltenango Guatemala, siglo XIX.

    Directory of Open Access Journals (Sweden)

    Anna Carla Ericastilla Samayoa

    2011-08-01

    Full Text Available La sociedad y el Estado – o cualquier otro espacio de síntesis del poder -, han tenido un conjunto de objetivos ligados al control, al ordenamiento y a la sanción de la sexualidad, ya que ha sido función estatal regir las relaciones entre los géneros. Los patrones de la sexualidad femenina son un producto histórico del poder masculino que ha definido lo que es necesario y deseable. En la presente ponencia se abordan los casos que implicaron comportamientos considerados ilícitos en los que se evidencia una voluntad de trasgresión social de las mujeres de los ideales de matrimonio y familia monogámica. Se abordan las tensiones existentes entre la preceptiva de la conducta considerada honorable y las conductas sexuales toleradas en la vida cotidiana, vinculada con los códigos de virilidad y feminidad apropiados que invocaban el significado diferenciado del honor masculino y femenino

  18. Gold nanoparticle-based microfluidic sensor for mercury detection

    DEFF Research Database (Denmark)

    Lafleur, Josiane P.; Jensen, Thomas Glasdam; Kutter, Jörg Peter

    2011-01-01

    The contamination of natural resources by human activity can have severe socio-economical impacts. Conventional methods of environmental analysis can be significantly improved by the development of portable microscale technologies for remote/field sensing. A gold nanoparticle-based lab-on-a-chip ......-on-a-chip device was developed for the rapid, in-field detection and quantification of mercury in aquatic environments. Rhodamine 6G functionalized gold nanoparticles allowed the on-chip fluorescence detection of mercury in aqueous samples with a limit of detection of 7 nM....

  19. Synthesis, characterization, cytotoxic and antitubercular activities of new gold(I) and gold(III) complexes containing ligands derived from carbohydrates.

    Science.gov (United States)

    Chaves, Joana Darc Souza; Damasceno, Jaqueline Lopes; Paula, Marcela Cristina Ferreira; de Oliveira, Pollyanna Francielli; Azevedo, Gustavo Chevitarese; Matos, Renato Camargo; Lourenço, Maria Cristina S; Tavares, Denise Crispim; Silva, Heveline; Fontes, Ana Paula Soares; de Almeida, Mauro Vieira

    2015-10-01

    Novel gold(I) and gold(III) complexes containing derivatives of D-galactose, D-ribose and D-glucono-1,5-lactone as ligands were synthesized and characterized by IR, (1)H, and (13)C NMR, high resolution mass spectra and cyclic voltammetry. The compounds were evaluated in vitro for their cytotoxicity against three types of tumor cells: cervical carcinoma (HeLa) breast adenocarcinoma (MCF-7) and glioblastoma (MO59J) and one non-tumor cell line: human lung fibroblasts (GM07492A). Their antitubercular activity was evaluated as well expressed as the minimum inhibitory concentration (MIC90) in μg/mL. In general, the gold(I) complexes were more active than gold(III) complexes, for example, the gold(I) complex (1) was about 8.8 times and 7.6 times more cytotoxic than gold(III) complex (8) in MO59J and MCF-7 cells, respectively. Ribose and alkyl phosphine derivative complexes were more active than galactose and aryl phosphine complexes. The presence of a thiazolidine ring did not improve the cytotoxicity. The study of the cytotoxic activity revealed effective antitumor activities for the gold(I) complexes, being more active than cisplatin in all the tested tumor cell lines. Gold(I) compounds (1), (2), (3), (4) and (6) exhibited relevant antitubercular activity even when compared with first line drugs such as rifampicin.

  20. La cultura del honor en la culpabilización de la mujer objeto de violación

    OpenAIRE

    Canto, Jesús M.; Perles, Fabiola; San Martín, Jesús

    2014-01-01

    Se analiza el papel que desempeña la cultura del honor en la culpabilización de las mujeres objeto de violación. Se obtiene que en los escenarios de violación en lo que previamente se daba algún tipo de intimidad entre la víctima y el agresor (violación por un conocido y violación marital), a medida que se puntúa más alto en la aceptación de los postulados de la cultura del honor, más se culpabiliza a la mujer.

  1. Facile green synthesis of variable metallic gold nanoparticle using Padina gymnospora, a brown marine macroalga

    Science.gov (United States)

    Singh, M.; Kalaivani, R.; Manikandan, S.; Sangeetha, N.; Kumaraguru, A. K.

    2013-04-01

    The process of development of reliable and eco-friendly metallic nanoparticles is an important step in the field of nanotechnology. To achieve this, use of natural sources like biological systems becomes essential. In the present work, extracellular biosynthesis of gold nanoparticles using Padina gymnospora has been attempted and achieved rapid formation of gold nanoparticles in a short duration. The UV-vis spectrum of the aqueous medium containing gold ion showed peak at 527 nm corresponding to the plasmon absorbance of gold nanoparticles. Scanning electron microscopy showed the formation of well-dispersed gold nanoparticles. FTIR spectra of brown alga confirmed that hydroxyl groups present in the algal polysaccharides were involved in the gold bioreduction. AFM analysis showed the results of particle sizes (53-67 nm) and average height of the particle roughness (60.0 nm). X-ray diffraction (XRD) spectrum of the gold nanoparticles exhibited Bragg reflections corresponding to gold nanoparticles. This environment-friendly method of biological gold nanoparticle synthesis can be applied potentially in various products that directly come in contact with the human body, such as cosmetics, and foods and consumer goods, besides medical applications.

  2. Structure and bonding in gold compounds

    International Nuclear Information System (INIS)

    Parish, R.V.

    1988-01-01

    Recent developments in chemical applications of 197 Au Moessbauer spectroscopy are reviewed. For gold(I) and gold(III), systematic variations in isomer shift and quadrupole splitting are seen as the ligands are changed; the effects of change in coordination number of the gold atoms are also systematic. Data for gold(II) systems involving gold-gold bonds lie between those for corresponding gold(I) and gold(III) materials, showing a small increase in isomer shift and a larger increase in quadrupole splitting as the oxidation state decreases; these trends are explained in terms of the structures. Data for mixed-metal cluster compounds are much more sensitive to structural effects than in homonuclear clusters. Both sets of data show systematic changes with increase in the number of metal atoms to which the gold atom is bound. The connectivity also influences the recoil-free fraction. (orig.)

  3. Gold nanoparticle (AuNPs) and gold nanopore (AuNPore) catalysts in organic synthesis.

    Science.gov (United States)

    Takale, Balaram S; Bao, Ming; Yamamoto, Yoshinori

    2014-04-07

    Organic synthesis using gold has gained tremendous attention in last few years, especially heterogeneous gold catalysis based on gold nanoparticles has made its place in almost all organic reactions, because of the robust and green nature of gold catalysts. In this context, gold nanopore (AuNPore) with a 3D metal framework is giving a new dimension to heterogeneous gold catalysts. Interestingly, AuNPore chemistry is proving better than gold nanoparticles based chemistry. In this review, along with recent advances, major discoveries in heterogeneous gold catalysis are discussed.

  4. Effect of Positive Psychology Elements on Job Pride and Honor with an Emphasis on Mediating Role of Communication among Faculty Members of Shiraz University of Medical Sciences

    Science.gov (United States)

    Hosein Kamani, Seyed Mohammad

    2017-01-01

    Job pride and honor is affected by various causes. Elements of positive psychology can be pointed out as one of them that in recent years has played an important role in organizational development. Hence, this study is to provide a prediction model about the impact of hope and resilience on job pride and honor with an emphasis on mediator role of…

  5. Grafting of Gold Nanoparticles on Glass Using Sputtered Gold Interlayers

    Directory of Open Access Journals (Sweden)

    Ondřej Kvítek

    2014-01-01

    Full Text Available Three-step preparation of nanostructured Au layer on glass substrate is described. The procedure starts with sputtered gold interlayer, followed by grafting with dithiols and final coverage with gold nanoparticles (AuNPs. Successful binding of dithiols on the sputtered Au film was confirmed by X-ray photoelectron spectroscopy measurement. AuNPs bound to the surface were observed using atomic force microscopy. Both single nanoparticles and their aggregates were observed. UV-Vis spectra show broadening of surface plasmon resonance peak after AuNPs binding caused by aggregation of AuNPs on the sample surface. Zeta potential measurements suggest that a large part of the dithiol molecules are preferentially bound to the gold interlayer via both –SH groups.

  6. Surface Chemistry of Gold Nanorods.

    Science.gov (United States)

    Burrows, Nathan D; Lin, Wayne; Hinman, Joshua G; Dennison, Jordan M; Vartanian, Ariane M; Abadeer, Nardine S; Grzincic, Elissa M; Jacob, Lisa M; Li, Ji; Murphy, Catherine J

    2016-10-04

    Gold nanorods have garnered a great deal of scientific interest because of their unique optical properties, and they have the potential to greatly impact many areas of science and technology. Understanding the structure and chemical makeup of their surfaces as well as how to tailor them is of paramount importance in the development of their successful applications. This Feature Article reviews the current understanding of the surface chemistry of as-synthesized gold nanorods, methods of tailoring the surface chemistry of gold nanorods with various inorganic and organic coatings/ligands, and the techniques employed to characterize ligands on the surface of gold nanorods as well as the associated measurement challenges. Specifically, we address the challenges of determining how thick the ligand shell is, how many ligands per nanorod are present on the surface, and where the ligands are located in regiospecific and mixed-ligand systems. We conclude with an outlook on the development of the surface chemistry of gold nanorods leading to the development of a synthetic nanoparticle surface chemistry toolbox analogous to that of synthetic organic chemistry and natural product synthesis.

  7. Balzac and human gait analysis.

    Science.gov (United States)

    Collado-Vázquez, S; Carrillo, J M

    2015-05-01

    People have been interested in movement analysis in general, and gait analysis in particular, since ancient times. Aristotle, Hippocrates, Galen, Leonardo da Vinci and Honoré de Balzac all used observation to analyse the gait of human beings. The purpose of this study is to compare Honoré de Balzac's writings with a scientific analysis of human gait. Honoré de Balzac's Theory of walking and other works by that author referring to gait. Honoré de Balzac had an interest in gait analysis, as demonstrated by his descriptions of characters which often include references to their way of walking. He also wrote a treatise entitled Theory of walking (Théorie de la demarche) in which he employed his keen observation skills to define gait using a literary style. He stated that the walking process is divided into phases and listed the factors that influence gait, such as personality, mood, height, weight, profession and social class, and also provided a description of the correct way of walking. Balzac considered gait analysis to be very important and this is reflected in both his character descriptions and Theory of walking, his analytical observation of gait. In our own technology-dominated times, this serves as a reminder of the importance of observation. Copyright © 2011 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

  8. Gold rush - A swarm dynamics in games

    Science.gov (United States)

    Zelinka, Ivan; Bukacek, Michal

    2017-07-01

    This paper is focused on swarm intelligence techniques and its practical use in computer games. The aim is to show how a swarm dynamics can be generated by multiplayer game, then recorded, analyzed and eventually controlled. In this paper we also discuss possibility to use swarm intelligence instead of game players. Based on our previous experiments two games, using swarm algorithms are mentioned briefly here. The first one is strategy game StarCraft: Brood War, and TicTacToe in which SOMA algorithm has also take a role of player against human player. Open research reported here has shown potential benefit of swarm computation in the field of strategy games and players strategy based on swarm behavior record and analysis. We propose new game called Gold Rush as an experimental environment for human or artificial swarm behavior and consequent analysis.

  9. Phage based green chemistry for gold ion reduction and gold retrieval.

    Science.gov (United States)

    Setyawati, Magdiel I; Xie, Jianping; Leong, David T

    2014-01-22

    The gold mining industry has taken its toll on the environment, triggering the development of more environmentally benign processes to alleviate the waste load release. Here, we demonstrate the use of bacteriophages (phages) for biosorption and bioreduction of gold ions from aqueous solution, which potentially can be applied to remediate gold ions from gold mining waste effluent. Phage has shown a remarkably efficient sorption of gold ions with a maximum gold adsorption capacity of 571 mg gold/g dry weight phage. The product of this phage mediated process is gold nanocrystals with the size of 30-630 nm. Biosorption and bioreduction processes are mediated by the ionic and covalent interaction between gold ions and the reducing groups on the phage protein coat. The strategy offers a simple, ecofriendly and feasible option to recover of gold ions to form readily recoverable products of gold nanoparticles within 24 h.

  10. Zepto-molar electrochemical detection of Brucella genome based on gold nanoribbons covered by gold nanoblooms

    Science.gov (United States)

    Rahi, Amid; Sattarahmady, Naghmeh; Heli, Hossein

    2015-12-01

    Gold nanoribbons covered by gold nanoblooms were sonoelectrodeposited on a polycrystalline gold surface at -1800 mV (vs. AgCl) with the assistance of ultrasound and co-occurrence of the hydrogen evolution reaction. The nanostructure, as a transducer, was utilized to immobilize a Brucella-specific probe and fabrication of a genosensor, and the process of immobilization and hybridization was detected by electrochemical methods, using methylene blue as a redox marker. The proposed method for detection of the complementary sequence, sequences with base-mismatched (one-, two- and three-base mismatches), and the sequence of non-complementary sequence was assayed. The fabricated genosensor was evaluated for the assay of the bacteria in the cultured and human samples without polymerase chain reactions (PCR). The genosensor could detect the complementary sequence with a calibration sensitivity of 0.40 μA dm3 mol-1, a linear concentration range of 10 zmol dm-3 to 10 pmol dm-3, and a detection limit of 1.71 zmol dm-3.

  11. Gold nanoparticles stabilized by chitosan

    International Nuclear Information System (INIS)

    Geraldes, Adriana N.; Oliveira, Maria Jose A.; Silva, Andressa A. da; Leal, Jessica; Batista, Jorge G.S.; Lugao, Ademar B.

    2015-01-01

    In our laboratory has been growing the interest in studying gold nanoparticles and for this reason, the aim of this work is report the first results of the effect of chitosan as stabilizer in gold nanoparticle formulation. AuNPs were synthesized by reducing hydrogen tetrachloroaurate (HAuCl 4 ) using NaBH 4 or gamma irradiation (25kGy) as reduction agent. The chitosan (3 mol L -1 ) was added at 0.5; 1.0 and 1.5 mL. The gold nanoparticles were characterized by UV-Vis absorption spectroscopy, X-ray diffraction (XRD) and Transmission electron microscopy (TEM). Their physical stability was determined using a UV-Vis spectrophotometer over one week during storage at room temperature. Absorption measurements indicated that the plasmon resonance wavelength appears at a wavelength around 530 nm. Has been observed that Chitosan in such quantities were not effective in stabilizing the AuNPs. (author)

  12. Aptamer biosensor for dopamine based on a gold electrode modified with carbon nanoparticles and thionine labeled gold nanoparticles as probe

    International Nuclear Information System (INIS)

    Xu, Yaqiong; Hun, Xu; Liu, Fang; Wen, Xiaolong; Luo, Xiliang

    2015-01-01

    We describe a biosensor for dopamine that is based on the use of a gold electrode modified with carbon nanoparticles (CNPs) coupled to thionine labeled gold nanoparticles (AuNPs) acting as signal amplifiers. The biosensor was constructed by first modifying the CNPs on the gold electrode and adsorbing the thionine on the surface of the AuNPs, and then linking the complementary strand of the dopamine aptamer to the AuNPs via gold-thiol chemistry. Next, dopamine aptamer is added and the duplex is formed on the surface. On addition of a sample containing dopamine, it will interact with aptamer and cause the release of the electrochemical probe which then will be adsorbed on the surface of the CNP-modified gold electrode and detected by differential pulse voltammetry. The current is linearly related to the concentration of dopamine in the 30 nM to 6.0 μM ranges. The detection limit is as low as 10 nM, and the RSD is 3.1 % at a 0.3 μM level (for n = 11). The protocol was successfully applied to the determination of dopamine in spiked human urine samples. We perceive that this method holds promise as a widely applicable platform for aptamer-based electrochemical detection of small molecules. (author)

  13. New Trends in Gold Catalysts

    Directory of Open Access Journals (Sweden)

    Leonarda F. Liotta

    2014-07-01

    Full Text Available Gold is an element that has fascinated mankind for millennia. The catalytic properties of gold have been a source of debate, due to its complete chemical inertness when in a bulk form, while it can oxidize CO at temperatures as low as ~200 K when in a nanocrystalline state, as discovered by Haruta in the late 1980s [1]. Since then, extensive activity in both applied and fundamental research on gold has been initiated. The importance of the catalysis by gold represents one of the fasted growing fields in science and is proven by the promising applications in several fields, such as green chemistry and environmental catalysis, in the synthesis of single-walled carbon nanotubes, as modifiers of Ni catalysts for methane steam and dry reforming reactions and in biological and electrochemistry applications. The range of reactions catalyzed by gold, as well as the suitability of different supports and the influence of the preparation conditions have been widely explored and optimized in applied research [2]. Gold catalysts appeared to be very different from the other noble metal-based catalysts, due to their marked dependence on the preparation method, which is crucial for the genesis of the catalytic activity. Several methods, including deposition-precipitation, chemical vapor deposition and cation adsorption, have been applied for the preparation of gold catalysts over reducible oxides, like TiO2. Among these methods, deposition-precipitation has been the most frequently employed method for Au loading, and it involves the use of tetrachloroauric (III acid as a precursor. On the other hand, the number of articles dealing with Au-loaded acidic supports is smaller than that on basic supports, possibly because the deposition of [AuCl4]− or [AuOHxCl4−x]− species on acidic supports is difficult, due to their very low point of zero charge. Despite this challenge, several groups have reported the use of acidic zeolites as supports for gold. Zeolites

  14. Nanobubble trouble on gold surfaces

    DEFF Research Database (Denmark)

    Holmberg, Maria; Kuhle, A.; Garnaes, J.

    2003-01-01

    When analyzing surfaces related to biosensors with in situ atomic force microscopy (AFM), the existence of nanobubbles called for our attention. The bubbles seem to form spontaneously when gold surfaces are immersed in clean water and are probably a general phenomenon at water-solid interfaces....... Besides from giving rise to undesired effects in, for example, biosensors, nanobubbles can also cause artifacts in AFM imaging. We have observed nanobubbles on unmodified gold surfaces, immersed in clean water, using standard silicon AFM probes. Nanobubbles can be made to disappear from contact mode AFM...

  15. Partners in the Parks: Field Guide to an Experiential Program in the National Parks. National Collegiate Honors Council Monograph Series

    Science.gov (United States)

    Digby, Joan

    2010-01-01

    The aim of Partners in the Parks (PITP) from its inception has been to introduce, or reintroduce, collegiate honors students to this country: not the transformed environment that we have constructed on its surface but the bedrock world upon which it rests. Like de Toqueville, Jefferson, Thoreau, Emerson, and so many others, these authors…

  16. Brno Studies in English. Volume Eight. Charisteria Iosepho Vachek Sexagenario Oblata (Festschrift in Honor of Josef Vachek's Sixtieth Birthday).

    Science.gov (United States)

    Firbas, Jan, Ed.; Hladky, Josef, Ed.

    This festscrift is presented in honor of Josef Vachek, founder of the linguistic section of the Department of English and American studies of the Purkyne University. Papers in the collection represent a wide spectrum of research and thought in linguistics and the English language and are authored by the following: (1) J. Firbas, Brno; (2) M.…

  17. Introductory Molecular Orbital Theory: An Honors General Chemistry Computational Lab as Implemented Using Three-Dimensional Modeling Software

    Science.gov (United States)

    Ruddick, Kristie R.; Parrill, Abby L.; Petersen, Richard L.

    2012-01-01

    In this study, a computational molecular orbital theory experiment was implemented in a first-semester honors general chemistry course. Students used the GAMESS (General Atomic and Molecular Electronic Structure System) quantum mechanical software (as implemented in ChemBio3D) to optimize the geometry for various small molecules. Extended Huckel…

  18. Courting the Best & the Brightest: Honors Colleges Mushroom across the Country in Both Two- and Four-Year Institutions

    Science.gov (United States)

    Hamilton, Kendra

    2004-01-01

    Honors colleges and programs are as individual as the schools that host them, but they all share some features in common: small classes, usually less than 20 students; interdisciplinary classes, often team-taught; and some kind of experiential education unit, from study abroad to internships to service learning. This article focuses on the…

  19. The Heritage of Herding and Southern Homicide: Examining the Ecological Foundations of the Code of Honor Thesis

    Science.gov (United States)

    Baller, Robert D.; Zevenbergen, Matthew P.; Messner, Steven F.

    2009-01-01

    The authors examine the ecological foundations of the thesis of a "code of honor" as an explanation for southern homicide. Specifically, they consider the effects of indicators of ethnic groups that migrated from herding economies (the Scotch-Irish), cattle and pig herding, and the relative importance of agricultural production across…

  20. An Evaluation of the Trends of Realism in Caldecott Winner and First Honor Books 1966-1986.

    Science.gov (United States)

    Smith, John A., Jr.; Napier, Georgia

    To determine if there were any consistent tendencies toward the abstract or toward impressionism in the illustration of children's books between the years 1966 and 1986, a study examined the illustrations of Caldecott winners and Honor books. The study replicated John Stewig's study (using his evaluation instrument) of the same topic which covered…

  1. A Means of Honorable Support: Art and Music in Women's Education in the Mid-Nineteenth Century

    Science.gov (United States)

    Nash, Margaret A.

    2013-01-01

    "The value of the Art Education becomes more and more apparent as a means of honorable support and of high culture and enjoyment," stated the catalog of Ingham University in western New York State in 1863. The Art Department there would prepare "pupils for Teachers and Practical Artists." This statement reveals some of the…

  2. Learning Strategies in Play during Basic Training for Medal of Honor and Call of Duty Video Games

    Science.gov (United States)

    Ziaeehezarjeribi, Yadi

    2010-01-01

    This study, based on experiential play methodology was used to explore student engagement while playing "Medal of Honor (2002)" and "Call of Duty (2003)". It identifies some of the key issues related to the use of video games and simulations during the training phase of game play. Research into the effects of gaming in education has been extremely…

  3. Questioning Honor: A Parent-Teacher Conflict over Excellence and Diversity in a USA Urban High School

    Science.gov (United States)

    Attanucci, Jane S.

    2004-01-01

    Parent-teacher relations are often characterized as highly conflictual in the educational literature, with scant empirical evidence of how the disagreements occur in everyday talk. Close analysis of a teacher's account of an intense conflict with a student's mother over the National Honor Society grounds the abstract discourses of merit and…

  4. A Novel Strategy for Synthesis of Gold Nanoparticle Self Assemblies

    NARCIS (Netherlands)

    Verma, Jyoti; Lal, Sumit; van Veen, Henk A.; van Noorden, Cornelis J. F.

    2014-01-01

    Gold nanoparticle self assemblies are one-dimensional structures of gold nanoparticles. Gold nanoparticle self assemblies exhibit unique physical properties and find applications in the development of biosensors. Methodologies currently available for lab-scale and commercial synthesis of gold

  5. Green synthesis of biocompatible gold nanoparticles using Fagopyrum esculentum leaf extract

    Science.gov (United States)

    Babu, Punuri Jayasekhar; Sharma, Pragya; Kalita, Mohan Chandra; Bora, Utpal

    2011-12-01

    This report describes the use of ethnolic extract of Fagopyrum esculentum leaves for the synthesis of gold nanoparticles. UV-visible spectroscopy analysis indicated the successful formation of gold nanoparticles. The synthesized nanoparticles were characterized by transmission electron microscopy (TEM), high resolution TEM (HRTEM) and were found to be spherical, hexagonal and triangular in shape with an average size of 8.3 nm. The crystalline nature of the gold nanoparticles was confirmed from X-ray diffraction (XRD) and selected-area electron diffraction (SAED) patterns. Fourier transform infrared (FT-IR) and energy-dispersive X-ray analysis (EDX) suggested the presence of organic biomolecules on the surface of the gold nanoparticles. Cytotoxicity tests against human HeLa, MCF-7 and IMR-32 cancer cell lines revealed that the gold nanoparticles were non-toxic and thus have potential for use in various biomedical applications.

  6. Ewing Symposium in Honor of Taro Takahashi: The controversial aspects of the contemporary [carbon] cycle

    Energy Technology Data Exchange (ETDEWEB)

    Broecker, Wallace Smith

    2001-12-31

    This Ewing Symposium in honor of Taro Takahashi's work on the carbon cycle was held at Lamont-Doherty Earth Observatory, Palisades, New York, on October 26-27, 2000. A program and set of abstracts are appended to this report. A summary of the meeting (included in this report) will be published in Global Biogeochemical Cycles. The theme of the symposium was the magnitude and cause of excess carbon storage on the north temperate continents. Disagreement exists on the relative roles of forest regrowth and fertilization by excess fixed nitrogen and carbon dioxide, as well as the distribution of this storage. Phenomena playing important roles include pre-anthropogenic gradients in carbon dioxide, the so-called rectification effect, uptake and release of carbon dioxide by the ocean, soil nitrogen dynamics, atmospheric carbon-13 gradients, and the role of fire.

  7. Symposium on Recent Advances in Experimental Mechanics : in honor of Isaac M. Daniel

    CERN Document Server

    2002-01-01

    This book contains 71 papers presented at the symposium on “Recent Advances in Experimental Mechanics” which was organized in honor of Professor Isaac M. Daniel. The symposium took place at Virginia Polytechnic Institute and State University on th June 23-28, 2002, in conjunction with the 14 US National Congress of Applied Mechanics. The book is a tribute to Isaac Daniel, a pioneer of experimental mechanics and composite materials, in recognition of his continuous, original, diversified and outstanding contributions for half a century. The book consists of invited papers written by leading experts in the field. It contains original contributions concerning the latest developments in experimental mechanics. It covers a wide range of subjects, including optical methods of stress analysis (photoelasticity, moiré, etc.), composite materials, sandwich construction, fracture mechanics, fatigue and damage, nondestructive evaluation, dynamic problems, fiber optic sensors, speckle metrology, digital image process...

  8. Relocating the history of science essays in honor of Kostas Gavroglu

    CERN Document Server

    Renn, Jurgen; Simoes, Ana

    2015-01-01

    This volume is put together in honor of a distinguished historian of science, Kostas Gavroglu, whose work has won international acclaim, and has been pivotal in establishing the discipline of history of science in Greece, its consolidation in other countries of the European Periphery, and the constructive dialogue of these emerging communities with an extended community of international scholars. The papers in the volume reflect Gavroglu’s broad range of intellectual interests and touch upon significant themes in recent history and philosophy of science. They include topics in the history of modern physical sciences, science and technology in the European periphery, integrated history and philosophy of science, historiographical considerations, and intersections with the history of mathematics, technology and contemporary issues. They are authored by eminent scholars whose academic and personal trajectories crossed with Gavroglu’s. The book will interest historians and philosophers of science and techno...

  9. Analytic number theory, approximation theory, and special functions in honor of Hari M. Srivastava

    CERN Document Server

    Rassias, Michael

    2014-01-01

    This book, in honor of Hari M. Srivastava, discusses essential developments in mathematical research in a variety of problems. It contains thirty-five articles, written by eminent scientists from the international mathematical community, including both research and survey works. Subjects covered include analytic number theory, combinatorics, special sequences of numbers and polynomials, analytic inequalities and applications, approximation of functions and quadratures, orthogonality, and special and complex functions. The mathematical results and open problems discussed in this book are presented in a simple and self-contained manner. The book contains an overview of old and new results, methods, and theories toward the solution of longstanding problems in a wide scientific field, as well as new results in rapidly progressing areas of research. The book will be useful for researchers and graduate students in the fields of mathematics, physics, and other computational and applied sciences.

  10. Optimization in science and engineering in honor of the 60th birthday of Panos M. Pardalos

    CERN Document Server

    Floudas, Christodoulos; Butenko, Sergiy

    2014-01-01

    Optimization in Science and Engineering is dedicated in honor of the 60th birthday of Distinguished Professor Panos M. Pardalos. Pardalos’s past and ongoing work has made a significant impact on several theoretical and applied areas in modern optimization. As tribute to the diversity of Dr. Pardalos’s work in Optimization, this book comprises a collection of contributions from experts in various fields of this rich and diverse area of science. Topics highlight recent developments and include: Deterministic global optimization Variational inequalities and equilibrium problems Approximation and complexity in numerical optimization Non-smooth optimization Statistical models and data mining Applications of optimization in medicine, energy systems, and complex network analysis This volume will be of great interest to graduate students, researchers, and practitioners, in the fields of optimization and engineering.

  11. Anonimo, “Totas honors e tuig faig benestan” (BdT 461.234

    Directory of Open Access Journals (Sweden)

    Marco Grimaldi

    2010-08-01

    Full Text Available This paper will examine an anonymous ‘planh’, “Totas honor e tuig faig benestan”, for the death of Manfred of Swabia, illegitimate son of Frederick II, who was killed in the battle of Benevento in 1266. The text is copied in a section of the ‘twin’ chansonniers I and K which contains mainly lyric laments (an exception in the troubadour manuscript tradition and for this reason will serve as a basis for a discussion of the concept of ‘documentary series’. The paper will also consider the author’s origin, probably Italian on the basis of the linguistic and metrical evidence, and attempt to place the planh more precisely within the context of the struggle between Charles of Anjou and Manfred, as well as illustrate the role played by political troubadour poetry at the Italian court of the last Swabians.

  12. Racism and the older voter? Arizona's rejection of a paid holiday to honor Martin Luther King.

    Science.gov (United States)

    Kastenbaum, R

    1991-01-01

    Two propositions that would have established a paid Martin Luther King holiday were defeated in Arizona's statewide elections of November 6, 1990. Communities and counties with high proportions of senior adult voters cast proportionately more votes against these propositions. Was this an example of racism among the primarily anglo senior adult voters of Arizona? Three models were proposed to account for the general pattern of election-related behavior as well as the vote itself: 1) proactive racist, 2) pragmatic self-interest, and 3) fortress mentality. It was suggested that proactive racism and pragmatic self-interest accounted for less of the opposition to a paid holiday honoring Martin Luther King than did a fortress mentality that has developed through a combination of circumstances. Attention is also given to the larger question of senior adults as perpetrators as well as victims of bigotry.

  13. Harmonic analysis, partial differential equations and applications in honor of Richard L. Wheeden

    CERN Document Server

    Franchi, Bruno; Lu, Guozhen; Perez, Carlos; Sawyer, Eric

    2017-01-01

    This is a collection of contributed papers by many eminent Harmonic Analysts and specialists of Partial Differential equations. The papers focus on weighted norm equalities for singular integrals, focusing wave equations, degenerate elliptic equations, Navier-Stokes flow in two dimensions and Poincare-Sobolev inequalities in the setting of metric spaces equipped with measures among others. Many topics considered in this volume stem from the interests of Richard L. Wheeden whose contributions to Potential Theory, singular integral theory and degenerate elliptic PDE theory this volume honors. Luis Caffarelli, Sagun Chanillo, Bruno Franchi, Cristian Guttierez, Xiaojun Huang, Carlos Kenig, Ermanno Lanconelli, Eric Sawyer and Alexander Volberg, are some of the many contributors to this volume. .

  14. Pursuing excellence in mathematics education essays in honor of Jeremy Kilpatrick

    CERN Document Server

    Silver, Edward

    2014-01-01

    ​Chapters in this book recognize the more than forty years of sustained and distinguished lifetime achievement in mathematics education research and development of Jeremy Kilpatrick. Including contributions from a variety of skilled mathematics educators, this text honors Jeremy Kilpatrick, reflecting on his groundbreaking papers, book chapters, and books - many of which are now standard references in the literature - on mathematical problem solving, the history of mathematics education, mathematical ability and proficiency, curriculum change and its history, global perspectives on mathematics education, and mathematics assessment. Many chapters also offer substantial contributions of their own on important themes, including mathematical problem solving, mathematics curriculum, the role of theory in mathematics education, the democratization of mathematics, and international perspectives on the professional field of mathematics education.​.

  15. From Comedy to the Sacramental Play: from Honor to Forgiveness in Lope de Vega

    Directory of Open Access Journals (Sweden)

    J. Enrique Duarte Lueiro

    2017-11-01

    Full Text Available The author of this article reviews the critical bibliography of the sacramental plays by Lope to show how scholars have always considered that this writer adapted elements and resources taken from his comedies into the sacramental plays. Actually, this article analyses the code of honor relevant in comic comedies and tragedies with different results. But this convention is also coherent with the sacramental genre, because it is supported by images and biblical metaphors and, in this case, they force a determined end. Equally, we have to take into consideration that the playwright employs other means specific of the auto sacramental to allow the allegory to operate and connect its two allegorical levels.

  16. Fiestas en honor a la Santa Muerte en el Caribe mexicano

    Directory of Open Access Journals (Sweden)

    Antonio Higuera Bonfil

    2015-07-01

    Full Text Available Se abordan tres fiestas en honor a la Santa Muerte en Chetumal. Se muestran los rasgos generales de las celebraciones organizadas anualmente por la parroquia del Señor de la Misericordia y la Santa Muerte, adscrita a la Iglesia Católica Tradicional México-Estados Unidos, así como por dos altares domésticos que operan como centros esotéricos. Caracterizar estas ocasiones permite entender la forma en que se ha desarrollado una práctica religiosa local, que lejos de tener una tradición única, alimenta rituales propios. Las diferentes estructuras locales permiten que los creyentes expresen su creencia mediante la inserción en la organización de estas fiestas.

  17. The geology of the gold deposits of Prestea gold belt of Ghana ...

    African Journals Online (AJOL)

    This paper presents the geology of the gold deposits along the Prestea gold belt of Ghana to assist exploration work for new orebodies along the belt. Prestea district is the third largest gold producer in West Africa after Obuasi and Tarkwa districts (over 250 metric tonnes Au during the last century). The gold deposits are ...

  18. Gold Nanoparticle Mediated Phototherapy for Cancer

    International Nuclear Information System (INIS)

    Yao, C.; Zhang, L.; Wang, J.; He, Y.; Xin, J.; Wang, S.; Xu, H.; Zhang, Z.

    2016-01-01

    Gold nanoparticles exhibit very unique physiochemical and optical properties, which now are extensively studied in range of medical diagnostic and therapeutic applications. In particular, gold nanoparticles show promise in the advancement of cancer treatments. This review will provide insights into the four different cancer treatments such as photothermal therapy, gold nanoparticle-aided photodynamic therapy, gold nanoparticle-aided radiation therapy, and their use as drug carrier. We also discuss the mechanism of every method and the adverse effects and its limitations

  19. Undergraduate honors students' images of science: Nature of scientific work and scientific knowledge

    Science.gov (United States)

    Wallace, Michael L.

    This exploratory study assessed the influence of an implicit, inquiry-oriented nature of science (NOS) instructional approach undertaken in an interdisciplinary college science course on undergraduate honor students' (UHS) understanding of the aspects of NOS for scientific work and scientific knowledge. In this study, the nature of scientific work concentrated upon the delineation of science from pseudoscience and the value scientists place on reproducibility. The nature of scientific knowledge concentrated upon how UHS view scientific theories and how they believe scientists utilize scientific theories in their research. The 39 UHS who participated in the study were non-science majors enrolled in a Honors College sponsored interdisciplinary science course where the instructors took an implicit NOS instructional approach. An open-ended assessment instrument, the UFO Scenario, was designed for the course and used to assess UHS' images of science at the beginning and end of the semester. The mixed-design study employed both qualitative and quantitative techniques to analyze the open-ended responses. The qualitative techniques of open and axial coding were utilized to find recurring themes within UHS' responses. McNemar's chi-square test for two dependent samples was used to identify whether any statistically significant changes occurred within responses from the beginning to the end of the semester. At the start of the study, the majority of UHS held mixed NOS views, but were able to accurately define what a scientific theory is and explicate how scientists utilize theories within scientific research. Postinstruction assessment indicated that UHS did not make significant gains in their understanding of the nature of scientific work or scientific knowledge and their overall images of science remained static. The results of the present study found implicit NOS instruction even with an extensive inquiry-oriented component was an ineffective approach for modifying UHS

  20. Introduction: A Symposium in Honor of Professor Sir John Meurig Thomas

    Science.gov (United States)

    Gai, P. L.; Saka, H.; Tomokiyo, Y.; Boyes, E. D.

    2002-02-01

    This issue is dedicated to Professor Sir John Meurig Thomas for his renowned contributions to electron microscopy in the chemical sciences. It is a collection of peer-reviewed leading articles in electron microscopy, based on the presentations at the Microscopy and Microanalysis (M&M) 2000 symposium, which was held to honor Professor Thomas's exceptional scientific leadership and wide-ranging fundamental contributions in the chemical applications of electron microscopy.The issue contains key papers by leading international researchers on the recent developments and applications of electron microscopy in the solid state and liquid state sciences. They include synthesis and characterization of silicon nitride nanorods, nanostructures of amorphous silica, electron microscopy studies of nanoscale structure and chemistry of Pt-Ru electrocatalysts of interest in direct methanol fuel cells, development of in situ wet-environmental transmission electron microscopy for the first nanoscale studies of dynamic liquid-catalyst reactions, strain analysis of silicon by finite element method and energy filtering convergent beam electron diffraction, applications of chemistry with electron microscopy, bismuth nanowires for applications in nanoelectronics technology, synthesis and characterization of quantum dots for superlattices and in situ electron microscopy at very high temperatures to study the motion of W5Si3 on [alpha][beta]-SiN3 substrates.We thank all the participants, including the invited speakers, contributors, and session chairs, who made the symposium successful. We also thank the authors and reviewers of the papers who worked assiduously towards the publication of this issue.We are very grateful to the Microscopy Society of America (MSA) for providing the opportunity to honor Professor Sir John Meurig Thomas. Organizational support from the MSA is also gratefully acknowledged.We thank Charles E. Lyman, editor in chief of Microscopy and Microanalysis for coordinating

  1. Lamellar multilayer hexadecylaniline-modified gold nanoparticle ...

    Indian Academy of Sciences (India)

    Organization of hexadecylaniline (HDA)-modified colloidal gold particles at the air-water interface and the formation thereafter of lamellar, multilayer films of gold nanoparticles by the Langmuir-Blodgett technique is described in this paper. Formation of HDA-capped gold nanoparticles is accomplished by a simple biphasic ...

  2. Lamellar multilayer hexadecylaniline-modified gold nanoparticle

    Indian Academy of Sciences (India)

    Organization of hexadecylaniline (HDA)-modified colloidal gold particles at the air-water interface and the formation thereafter of lamellar, multilayer films of gold nanoparticles by the Langmuir-Blodgett technique is described in this paper. Formation of HDA-capped gold nanoparticles is accomplished by a simple biphasic ...

  3. Highly active thermally stable nanoporous gold catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Biener, Juergen; Wittstock, Arne; Biener, Monika M.; Bagge-Hansen, Michael; Baeumer, Marcus; Wichmann, Andre; Neuman, Bjoern

    2016-12-20

    In one embodiment, a system includes a nanoporous gold structure and a plurality of oxide particles deposited on the nanoporous gold structure; the oxide particles are characterized by a crystalline phase. In another embodiment, a method includes depositing oxide nanoparticles on a nanoporous gold support to form an active structure and functionalizing the deposited oxide nanoparticles.

  4. Gold and Silver Extraction from Leach Solutions

    OpenAIRE

    Bagdaulet K. Kenzhaliyev; Renata R. Iskhakova; Zamzagul D. Dosymbaeva; Esen N. Sulejmenov

    2014-01-01

    There has been carried out an investigation on the extraction of gold and silver from thiosulfate solutions: standard test and technological solutions of chemical and electrochemical leaching. The influence of related metals on the process of extracting gold from solution was studied. There has been conducted a comparative study of the IR spectra of solutions after the sorption of gold, silver and related metals.

  5. Ultrafast vibrations of gold nanorings

    DEFF Research Database (Denmark)

    Kelf, T; Tanaka, Y; Matsuda, O

    2011-01-01

    We investigate the vibrational modes of gold nanorings on a silica substrate with an ultrafast optical technique. By comparison with numerical simulations, we identify several resonances in the gigahertz range associated with axially symmetric deformations of the nanoring and substrate. We...

  6. [Biosynthesis of gold nanoparticles by Azospirillum brasilense].

    Science.gov (United States)

    Kupriashina, M A; Vetchinkina, E P; Burov, A M; Ponomareva, E G; Nikitina, V E

    2014-01-01

    Plant-associated nitrogen-fixing soil bacteria Azospirillum brasilense were shown to reduce the gold of chloroauric acid to elemental gold, resulting in formation of gold nanoparicles. Extracellular phenoloxidizing enzymes (laccases and Mn peroxidases) were shown to participate in reduction of Au+3 (HAuCl4) to Au(0). Transmission electron microscopy revealed accumulation of colloidal gold nanoparticles of diverse shape in the culture liquid of A. brasilense strains Sp245 and Sp7. The size of the electron-dense nanospheres was 5 to 50 nm, and the size of nanoprisms varied from 5 to 300 nm. The tentative mechanism responsible for formation of gold nanoparticles is discussed.

  7. Ultrasonic inspection of fake gold jewelry

    Science.gov (United States)

    Pauzi Ismail, Mohamad; Sani, Suhairy; Shofri, Faris Syazwan bin Mohd; Harun, Mohd.; Omar, Norlaili Binti

    2018-01-01

    Hollow jewelry made from combination of gold and other material was found in the market. At the outside it is made of gold and the inside layer is made of other material. X-ray fluorescent method cannot detect the inside material that was covered by gold. This paper explained the experimental result of ultrasonic inspection of fake gold used for jewelry. The ultrasonic pulse echo contact method was used to measure longitudinal wave velocity in the gold jewelry. The results of measurements are explained and discussed.

  8. Surface vertical deposition for gold nanoparticle film

    International Nuclear Information System (INIS)

    Diao, J J; Qiu, F S; Chen, G D; Reeves, M E

    2003-01-01

    In this rapid communication, we present the surface vertical deposition (SVD) method to synthesize the gold nanoparticle films. Under conditions where the surface of the gold nanoparticle suspension descends slowly by evaporation, the gold nanoparticles in the solid-liquid-gas junction of the suspension aggregate together on the substrate by the force of solid and liquid interface. When the surface properties of the substrate and colloidal nanoparticle suspension define for the SVD, the density of gold nanoparticles in the thin film made by SVD only depends on the descending velocity of the suspension surface and on the concentration of the gold nanoparticle suspension. (rapid communication)

  9. Anti-trypanosomal activity of cationic N-heterocyclic carbene gold(I) complexes.

    Science.gov (United States)

    Winter, Isabel; Lockhauserbäumer, Julia; Lallinger-Kube, Gertrud; Schobert, Rainer; Ersfeld, Klaus; Biersack, Bernhard

    2017-06-01

    Two gold(I) N-heterocyclic carbene complexes 1a and 1b were tested for their anti-trypanosomal activity against Trypanosoma brucei parasites. Both gold compounds exhibited excellent anti-trypanosomal activity (IC 50 =0.9-3.0nM). The effects of the gold complexes 1a and 1b on the T. b. brucei cytoskeleton were evaluated. Rapid detachment of the flagellum from the cell body occurred after treatment with the gold complexes. In addition, a quick and complete degeneration of the parasitic cytoskeleton was induced by the gold complexes, only the microtubules of the detached flagellum remained intact. Both gold compounds 1a and 1b feature selective anti-trypanosomal agents and were distinctly more active against T. b. brucei cells than against human HeLa cells. Thus, the gold complexes 1a and 1b feature promising drug candidates for the treatment of trypanosome infections such as sleeping sickness (human African Trypanosomiasis caused by Trypanosoma brucei parasites). Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Gold and not so real gold in Medieval treatises

    Directory of Open Access Journals (Sweden)

    Srebrenka Bogovic-Zeskoski

    2015-01-01

    Full Text Available The aim of this study is to evidence diverse materials and processes used by artisans (and alchemists required to synthesize a visually viable replacement for gold. The emphasis of the research is upon the production of mosaic gold or porporina, a pigment that has survived into modern times, which was used as ink and as paint. Base metals, mostly tin, but also alloys were used both into foils coated with glazes and varnishes and as pigment. The research focuses upon recipes documented in treatises dating from Antiquity to the late Medieval period (ca. 1500 and an attempt is made to answer two questions. In the first place, why was there a need for a surrogate? Secondly, why are there so few tangible examples detected on surviving artifacts? In conclusion, an argument is offered pointing out that, although much can be learned by scientific examination of artifacts, textual analysis is equally important and necessary to unravel mysteries of ancient technologies

  11. Nanotoxicity of gold and gold-cobalt nanoalloy.

    Science.gov (United States)

    Girgis, E; Khalil, W K B; Emam, A N; Mohamed, M B; Rao, K V

    2012-05-21

    Nanotoxicology test of gold nanoparticles (Au NPs) and gold-cobalt (Au-Co) nanoalloy is an important step in their safety evaluation for biomedical applications. The Au and Au-Co NPs were prepared by reducing the metal ions using sodium borohydride (NaBH(4)) in the presence of polyvinyl pyrrolidone (PVP) as a capping material. The average size and shape of the nanoparticles (NPs) were characterized using high resolution transmission electron microscopy (HRTEM). Cobalt presence in the nanoalloy was confirmed by energy dispersive X-ray spectroscopy (EDX) analysis, and the magnetic properties of these particles were determined using a vibrating sample magnetometer (VSM). The Gold and gold-cobalt NPs of average size 15 ± 1.5 nm were administered orally to mice with a dose of 80, 160, and 320 mg/kg per body weight (bw) using gavages. Samples were collected after 7 and 14 days of the treatment. The results indicated that the Au-Co NPs were able to induce significant alteration in the tumor-initiating genes associated with an increase of micronuclei (MNs) formation and generation of DNA adduct (8-hydroxy-2-deoxyguanosine, 8-OHdG) as well as a reduction in the glutathione peroxidase activity. This action of Au-Co NPs was observed using 160 and 320 mg/kg bw at both time intervals. However, Au NPs had much lower effects than Au-Co NPs on alteration in the tumor-initiating genes, frequency of MNs, and generation of 8-OHdG as well as glutathione peroxidase activity except with the highest dose of Au NPs. This study suggests that the potential to cause in vivo genetic and antioxidant enzyme alterations due to the treatment by Au-Co nanoalloy may be attributed to the increase in oxidative stress in mice.

  12. THE CYANIDE LEACH TECHNOLOGY IN GOLD AND SILVER MINING HARMFUL EFFECTS AND SUGGESTIONS FOR REMEDYING

    OpenAIRE

    Judit PETRES

    2013-01-01

    The region named Roşia Montană became famous due to its rich mineral resources. The most precious treasure which has been found is the gold. A state-run gold mine functioned for many years and the continuous pollution due to the gold extraction became very dangerous. All these cyanide-containing waste are hazardous to wildlife, natural resources and human health if not properly managed. The consequences of cyanide hazards may be devastating, sometimes killing everything for several miles down...

  13. Isolation of HL-60 cancer cells from the human serum sample using MnO2-PEI/Ni/Au/aptamer as a novel nanomotor and electrochemical determination of thereof by aptamer/gold nanoparticles-poly(3,4-ethylene dioxythiophene) modified GC electrode.

    Science.gov (United States)

    Amouzadeh Tabrizi, Mahmoud; Shamsipur, Mojtaba; Saber, Reza; Sarkar, Saeed

    2018-07-01

    Herein, aptamer-modified self-propelled nanomotors were used for transportation of human promyelocytic leukemia cells (HL-60) from a human serum sample. For this purpose, the fabricated manganese oxide nanosheets-polyethyleneimine decorated with nickel/gold nanoparticles (MnO 2 -PEI/Ni/Au) as nanomotors were added to a vial containing thiolated aptamer KH1C12 solution as a capture aptamer to attach to the gold nanoparticles on the surface of nanomotors covalently. The aptamer-modified self-propelled nanomotors (aptamer KH1C12 /nanomotors) were then separated by placing the vial in a magnetic stand. The aptamer-modified self-propelled nanomotors were rinsed three times with water to remove the non-attached aptamers. Then, the resulting aptamer KH1C12 /nanomotors were applied for the on-the-fly" transporting of HL-60 cancer cell from a human serum sample. To release of the captured HL-60 cancer cells, the complementary nucleotide sequences of KH1C12 aptamer solution (releasing aptamer) that has a with capture aptamer was added to phosphate buffer solution (1 M, pH 7.4) containing HL-60/aptamer KH1C12 /nanomotors. Because of the high affinity of capture aptamer to complementary nucleotide sequences of aptamer KH1C12 , the HL-60 cancer cells released on the surface of aptamer KH1C12 /nanomotors into the solution. The second goal of the present work was determining the concentration of HL-60 cancer cell in the human serum samples. The electrochemical impedance spectroscopy technique (EIS) was used for the determination of HL-60 cancer cell. The concentration of separated cancer cell was determined by aptamer/gold nanoparticles-poly(3,4-ethylene dioxythiophene) modified GC electrode (GC/PEDOT-Au nano /aptamer KH1C12 ). The proposed aptasensor exhibited a good response to the concentration of HL-60 cancer cells in the range of 2.5 × 10 1 to 5 × 10 5 cells mL -1 with a low limit of detection of 250 cells mL -1 . Copyright © 2018 Elsevier B.V. All rights reserved.

  14. CMS Industries awarded gold, crystal

    CERN Multimedia

    2006-01-01

    The CMS collaboration honoured 10 of its top suppliers in the seventh annual awards ceremony The representatives of the firms that recieved the CMS Gold and Crystal Awards stand with their awards after the ceremony. The seventh annual CMS Awards ceremony was held on Monday 13 March to recognize the industries that have made substantial contributions to the construction of the collaboration's detector. Nine international firms received Gold Awards, and General Tecnica of Italy received the prestigious Crystal Award. Representatives from the companies attended the ceremony during the plenary session of CMS week. 'The role of CERN, its machines and experiments, beyond particle physics is to push the development of equipment technologies related to high-energy physics,'said CMS Awards Coordinator Domenico Campi. 'All of these industries must go beyond the technologies that are currently available.' Without the involvement of good companies over the years, the construction of the CMS detector wouldn't be possible...

  15. Byzantine gold coins and jewellery

    International Nuclear Information System (INIS)

    Oddy, A.; La Niece, S.

    1986-01-01

    The article deals with the dating of Byzantine gold coinage. The results of such a study are of fundamental importance for the study of the economic history of the later Byzantine Empire and they are also of importance for the historian of technology when studying the composition of the contemporary Byzantine jewellery. Although Carbon-14 dating cannot be used as a method af dating, historians can still benefit from the analysis of the alloy of which the antiquity is made, as this is sometimes characteristic of the period in which it was used. A number of pieces of Byzantine jewellery has been analysed by x-ray fluorescence analysis, after first gently abrading a small area of the surface of the gold with the carborundum paper in an inconspicious position on the back or side of the object. A table is given on the results of this analysis

  16. Distribution and composition of gold in porphyry gold systems: example from the Biely Vrch deposit, Slovakia

    Science.gov (United States)

    Koděra, Peter; Kozák, Jaroslav; Brčeková, Jana; Chovan, Martin; Lexa, Jaroslav; Jánošík, Michal; Biroň, Adrián; Uhlík, Peter; Bakos, František

    2018-03-01

    The Biely Vrch deposit in the Western Carpathians is assigned to the shallow, sulfide-poor porphyry gold deposit type and has an exceptionally low Cu/Au ratio. According to 3-D geochemical models, there is a limited spatial correlation between Au and Cu due to the primary introduction of gold by a salt melt and Cu by low-density vapor. Despite a rough spatial correlation of gold grades with quartz stockwork intensity, gold is hosted mostly by altered rock, exclusively in native form. Three main gold mineral assemblages were recognized here. In the deepest parts of the system, the K- and Ca-Na silicate gold assemblage is associated with minerals of high-temperature alteration (plagioclase, K-feldspar, actinolite), with gold grades and fineness depending on depth and potassium content of the host rock: K-silicate alteration hosts the lowest fineness gold ( 914), whereas Ca-Na silicate alteration has the highest ( 983). The intermediate argillic gold assemblage is the most widespread, with gold hosted mainly by chlorite, illite, smectite, and interstratified illite-chlorite-smectite minerals. The gold fineness is mostly variable (875-990) and inherited from the former gold mineral assemblages. The latest advanced argillic gold assemblage has its gold mostly in kaolinite. The extremely high fineness ( 994) results from gold remobilization by late-stage aqueous magmatic-hydrothermal fluids. Uncommon bonanza-grade appears where the earlier gold mineral assemblages were further enriched by this remobilized gold. Primary precipitation of gold occurred during ascent and cooling of salt melts at 450 to 309 °C, mostly during retrograde quartz solubility.

  17. Subfemtomolar electrochemical detection of target DNA by catalytic enlargement of the hybridized gold nanoparticle labels

    OpenAIRE

    Rochelet-Dequaire, Murielle; Limoges, Benoit; Brossier, Pierre

    2006-01-01

    7 pages; International audience; After showing the failure of conventional gold-enhancement procedures to amplify the gold nanoparticle-based electrochemical transduction of DNA hybridization in polystyrene microwells, a new efficient protocol was developed and evaluated for the sensitive quantification of a 35 base-pair human cytomegalovirus nucleic acid target (tDNA). In this assay, the hybridization of the target adsorbed on the bottom of microwells with an oligonucleotide-modified Au nano...

  18. Gold Nanocages for Biomedical Applications**

    OpenAIRE

    Skrabalak, Sara E.; Chen, Jingyi; Au, Leslie; Lu, Xianmao; Li, Xingde; Xia, Younan

    2007-01-01

    Nanostructured materials provide a promising platform for early cancer detection and treatment. Here we highlight recent advances in the synthesis and use of Au nanocages for such biomedical applications. Gold nanocages represent a novel class of nanostructures, which can be prepared via a remarkably simple route based on the galvanic replacement reaction between Ag nanocubes and HAuCl4. The Au nanocages have a tunable surface plasmon resonance peak that extends into the near-infrared, where ...

  19. Extinction Coefficient of Gold Nanostars

    OpenAIRE

    de Puig, Helena; Tam, Justina O.; Yen, Chun-Wan; Gehrke, Lee; Hamad-Schifferli, Kimberly

    2015-01-01

    Gold nanostars (NStars) are highly attractive for biological applications due to their surface chemistry, facile synthesis and optical properties. Here, we synthesize NStars in HEPES buffer at different HEPES/Au ratios, producing NStars of different sizes and shapes, and therefore varying optical properties. We measure the extinction coefficient of the synthesized NStars at their maximum surface plasmon resonances (SPR), which range from 5.7 × 108 to 26.8 × 108 M−1cm−1. Measured values correl...

  20. Gold, currencies and market efficiency

    Czech Academy of Sciences Publication Activity Database

    Krištoufek, Ladislav; Vošvrda, Miloslav

    2016-01-01

    Roč. 449, č. 1 (2016), s. 27-34 ISSN 0378-4371 R&D Projects: GA ČR(CZ) GBP402/12/G097 Institutional support: RVO:67985556 Keywords : Efficient market hypothesis, * Gold * Currencies, * Fractal dimension * Entropy * Long-Term memory Subject RIV: AH - Economics Impact factor: 2.243, year: 2016 http://library.utia.cas.cz/separaty/2016/E/kristoufek-0455876.pdf

  1. Biomolecular Assembly of Gold Nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Micheel, Christine Marya [Univ. of California, Berkeley, CA (United States)

    2005-05-20

    Over the past ten years, methods have been developed to construct discrete nanostructures using nanocrystals and biomolecules. While these frequently consist of gold nanocrystals and DNA, semiconductor nanocrystals as well as antibodies and enzymes have also been used. One example of discrete nanostructures is dimers of gold nanocrystals linked together with complementary DNA. This type of nanostructure is also known as a nanocrystal molecule. Discrete nanostructures of this kind have a number of potential applications, from highly parallel self-assembly of electronics components and rapid read-out of DNA computations to biological imaging and a variety of bioassays. My research focused in three main areas. The first area, the refinement of electrophoresis as a purification and characterization method, included application of agarose gel electrophoresis to the purification of discrete gold nanocrystal/DNA conjugates and nanocrystal molecules, as well as development of a more detailed understanding of the hydrodynamic behavior of these materials in gels. The second area, the development of methods for quantitative analysis of transmission electron microscope data, used computer programs written to find pair correlations as well as higher order correlations. With these programs, it is possible to reliably locate and measure nanocrystal molecules in TEM images. The final area of research explored the use of DNA ligase in the formation of nanocrystal molecules. Synthesis of dimers of gold particles linked with a single strand of DNA possible through the use of DNA ligase opens the possibility for amplification of nanostructures in a manner similar to polymerase chain reaction. These three areas are discussed in the context of the work in the Alivisatos group, as well as the field as a whole.

  2. Jabiluka gold-uranium project

    International Nuclear Information System (INIS)

    1988-01-01

    The Jabiluka gold-uranium deposit, 230km east of Darwin in the Alligator Rivers Region of the Northern Territory, was discovered by Pancontinental Mining Limited in 1971. Jabiluka, with reserves in excess of 200,000 tonnes of contained U 3 O 8 in two deposits 500 metres apart, is the world's largest high grade uranium deposit and also contains nearly 12 tonnes of gold. It is proposed that only the larger deposit, Jabiluka II will be mined - by underground extraction methods, and that 275,000 tonnes of ore per year will be mined and processed to produce 1,500 tonnes of U 3 O 8 and up to 30,000 oz of gold. The revenue from the uranium sales is estimated to be of the order of A$100 million per year at A$30/lb. By the end of 1982 all necessary mining and environmental approvals had been obtained and significant marketing progress made. With the Australian Labor Party winning Commonwealth Government in the 1983 election, Pancontinental's permission to seek sales contracts was withdrawn and development of the Jabiluka deposit ceased. Jabiluka remains undeveloped - awaiting a change in Australian Government policy on uranium. figs., maps

  3. Bárbara Mujica, ed., Shakespeare and the Spanish «Comedia». Translation, Interpretation, Performance. Essays in Honor of Susan L. Fischer

    Directory of Open Access Journals (Sweden)

    Alejandro García-Reidy

    2016-01-01

    Full Text Available Reseña de Bárbara Mujica, ed., Shakespeare and the Spanish «Comedia». Translation, Interpretation, Performance. Essays in Honor of Susan L. Fischer, Bucknell University Press, Lewisburg, 2013, 298 pp. ISBN 9781611485172.

  4. Quantification and Prediction of Bulk Gold Fineness at Placer Gold Mines: A New Zealand Example

    Directory of Open Access Journals (Sweden)

    Dave Craw

    2017-11-01

    Full Text Available This study documents the bulk Au fineness (Au parts per thousand of the bullion from a placer gold mine in southern New Zealand. The compositions of doré bars produced approximately every 10 days over nearly three years is compared to the range of compositions of gold particles which have been extracted. Silver is the principal impurity in the gold, and the doré bars contained 2–3 wt % Ag over the period examined. At the scale of a typical individual 0.5 mm gold particle, there are three different types of gold: an Ag-bearing core (2–9 wt % Ag, a 10–50 µm wide Ag-poor rim (typically <1 wt % Ag, and micron scale overgrowth gold (0% Ag. The overgrowths are volumetrically negligible, and the average Ag content of a gold particle is controlled principally by the proportions of core and rim gold. The rims have been formed by recrystallisation of deformed core gold, with associated leaching of the Ag from the recrystallised gold. The volumetric proportion of cores has decreased with increasing flattening of gold particles, and highly flattened and folded flakes have little or no remnant cores. The bulk Au fineness of doré bars from the mine has decreased from ~980 to ~970 as the mine progressed upstream in a Pleistocene paleochannel because the upstream gold has been less flattened than the downstream gold.

  5. International conference on "Photosynthesis Research for Sustainability-2016" : In honor of Nathan Nelson and Turhan Nejat Veziroğlu.

    Science.gov (United States)

    Tsygankov, Anatoly A; Allakhverdiev, Suleyman I; Tomo, Tatsuya; Govindjee

    2017-02-01

    During June 19-26, 2016, an international conference ( http://photosynthesis2016.cellreg.org/ ) on "Photosynthesis Research for Sustainability-2016" was held in honor of Nathan Nelson and Turhan Nejat Veziroğlu at the Institute of Basic Biological Problems, Russian Academy of Sciences, formerly Institute of Photosynthesis, Academy of Sciences of the USSR, Pushchino, Russia. Further, this conference celebrated the 50th anniversary of the Institute. We provide here a brief introduction and key contributions of the two honored scientists, and then information on the conference, on the speakers, and the program. A special feature of this conference was the awards given to several young investigators, who are recognized in this Report. Several photographs are included to show the excellent ambience at this conference. We invite the readers to the next conference on "Photosynthesis and Hydrogen Energy Research for Sustainability-2017", which will honor A.S. Raghavendra (of University of Hyderabad), William Cramer (of Purdue University) and Govindjee (of University of Illinois at Urbana-Champaign); it will be held during the Fall of 2017 (from October 30 to November 4), at the University of Hyderabad, Hyderabad, India. See .

  6. CO extrusion in homogeneous gold catalysis: reactivity of gold acyl species generated through water addition to gold vinylidenes.

    Science.gov (United States)

    Bucher, Janina; Stößer, Tim; Rudolph, Matthias; Rominger, Frank; Hashmi, A Stephen K

    2015-01-26

    Herein, we describe a new gold-catalyzed decarbonylative indene synthesis. Synergistic σ,π-activation of diyne substrates leads to gold vinylidene intermediates, which upon addition of water are transformed into gold acyl species, a type of organogold compound hitherto only scarcely reported. The latter are shown to undergo extrusion of CO, an elementary step completely unknown for homogeneous gold catalysis. By tuning the electronic and steric properties of the starting diyne systems, this new reactivity could be exploited for the synthesis of indene derivatives in high yields. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Technology, organization and economic structure essays in honor of Prof. Isamu Yamada

    CERN Document Server

    Beckmann, Martin

    1983-01-01

    The essays in this volume were presented to Professor Isamu Yamada in honor of his seventy-third birthday. In view of his many professional contributions and associations, a single volume of essays is really insufficient to house the works of all those who wish to be part of a venture of this kind. Therefore, the editors would like to apologize to those friends and well-wishers of Professor Yamada who could not be accommodated in this volume. Born in Nagoya in 1909, Professor Yamada began his brilliant career at Nagoya Commercial College where he studied economics, statistics, mathematics and physics. After serving as a Professor of Economics and Statistics at Yokohama College between 1939-1940, Professor Yamada moved to Hitotsubashi University in Tokyo, where he served as a Professor of Econometrics until his retirement in 1973. Currently, he is teaching at Asia University as a Professor of Economics and Statistics. During his long tenure at Hitotsubashi University (where Professor Ichiro Nakayama, a "Japane...

  8. Honor, brotherhood, and the corporate ethos of London's Barber-Surgeons' Company, 1570-1640.

    Science.gov (United States)

    Chamberland, Celeste

    2009-07-01

    As the largest and most civically active body of medical practitioners in the late Tudor and early Stuart period, surgeons played a vital role in London's urban landscape, but remained precariously vulnerable to abasement due to the regular contact with death and disease necessitated by their work. Based on an analysis of guild records, printed surgical manuals, and conduct literature, this study explores the emergent corporate ethos of London's Barber-Surgeons' Company and addresses the identity formation of surgeons in the late-sixteenth and early-seventeenth centuries. By implementing codes of conduct and uniform standards of practice, punishing transgressions of propriety, and developing legislation to limit the activities of unlicensed and foreign practitioners, Company officers ardently sought social and occupational legitimacy within a milieu characterized by a tremendous emphasis on status and hierarchy. Rooted in methodology drawn from the social history of medicine and cultural anthropology, this study argues that in response to the persistent stigma associated with their work and London's increasingly prevalent culture of credit, surgeons, like other artisanal groups, sought to enhance their social legitimacy and occupational respectability by manipulating contemporary social rituals, reinforcing the honorable associations of their work, and preserving the veneer of brotherhood and camaraderie.

  9. The STTI Practice-Academe Innovative Collaboration Award: honoring innovation, partnership, and excellence.

    Science.gov (United States)

    Kirschling, Jane Marie; Erickson, Jeanette Ives

    2010-09-01

    To describe the benefits and barriers associated with practice-academe partnerships and introduce Sigma Theta Tau International's (STTI's) Practice-Academe Innovative Collaboration Award and the 2009 award recipients. In 2008, STTI created the CNO-Dean Advisory Council and charged it with reviewing the state of practice-academe collaborations and developing strategies for optimizing how chief nursing officers (CNOs) and deans work together to advance the profession and discipline of nursing. The Council, in turn, developed the Practice-Academe Innovative Collaboration Award to encourage collaboration across sectors, recognize innovative collaborative efforts, and spotlight best practices. A call for award submissions resulted in 24 applications from around the globe. An award winner and seven initiatives receiving honorable mentions were selected. The winning initiatives reflect innovative academe-service partnerships that advance evidence-based practice, nursing education, nursing research, and patient care. The proposals were distinguished by their collaborators' shared vision and unity of purpose, ability to leverage strengths and resources, and willingness to recognize opportunities and take risks. By partnering with one another, nurses in academe and in service settings can directly impact nursing education and practice, often effecting changes and achieving outcomes that are more extensive and powerful than could be achieved by working alone. The award-winning initiatives represent best practices for bridging the practice-academe divide and can serve as guides for nurse leaders in both settings.

  10. Honoring the Medicine: searching for the embodiment of spiritual commitment and philosophy for student physicians.

    Science.gov (United States)

    Roseman, Janet Lynn

    2014-01-01

    Honoring the Medicine is a project that grew from an assignment that I created for an online course I developed entitled "Introduction to Spirituality and Medicine." In an effort to create a consciousness that would explore the sacred oaths of the practice of medicine, I asked medical students who took the course to write their own sacred oath of healing that they would carry into their practice of medicine. Participants were asked to read the Hippocratic Oath and the Osteopathic Oath and to reflect on the ethical and humanistic aspects of each. Participants identified various areas of importance including the integration of mind, body and soul, empathy, compassion, and respect. Every participant identified their own attributes of healing. This exemplifies how 1 community--the medical community--can search deeper inside themselves to create a sacred model for humanistic medicine. This model is one that identifies attributes that all communities can practice in their lives, for the humanistic model touches every community and every community member.

  11. Application of Gold Nanoparticles to Paint Colorants

    Science.gov (United States)

    Ishibashi, Hideo

    Metal nanoparticles possess unique properties that they do not exhibit in their bulk states. One of these properties is the color due to surface plasmon resonance. Gold nanoparticles appear red. This color has been utilized in glass for a long long time. In recent years, highly concentrated pastes of gold and silver nanoparticles have been successfully produced by using a special type of protective polymer and a mild reductant. The paste of gold nanoparticles can be used for paint and other materials as red colorants. In this article,application examples of gold nanoparticles as colorant are introduced. Recently, methods for producing bimetal nanoparticles such as gold/silver and gold/copper have been developed. These nanoparticles allow colors from yellow to green to be created. These methods and colors they produce are also described in this article.

  12. Linear Optical Properties of Gold Colloid

    Directory of Open Access Journals (Sweden)

    Jingmin XIA

    2015-11-01

    Full Text Available Gold colloid was prepared by reducing HAuCl4·4H2O with Na3C6H5O7·2H2O. The morphology, size of gold nanoparticles and the optical property of colloid were characterized by transmission electron microscope and UV-Vis spectrophotometer, respectively. It shows that the gold nanoparticles are in the shape of spheres with diameters less than 8 nm, and the surface plasmon resonance absorption peak is located at about 438 nm. As the volume fraction of gold particles increases, the intensity of absorption peak strengthens. The optical property of gold colloid was analyzed by Maxwell-Garnett (MG effective medium theory in the company of Drude dispersion model. The results show that the matrix dielectric constant is a main factor, which influences the optical property of gold colloid.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9558

  13. Fabrication of Gold Nanoparticles Doped DVB Foams

    International Nuclear Information System (INIS)

    Fang Yu; Luo Xuan; Fan Yongheng; Zhang Qingjun; Ren Hongbo; Xiao Lei

    2009-01-01

    The fabrication of gold nanoparticles doped low density DVB foams was researched, which can be used as ICF target materials. By high internal phase emulsion (HIPE) method, gold nanoparticles doped low density DVB foams were prepared, with gold nanoparticles dissolved in inner phase. The results show that the content of Au in the gold nanoparticles doped DVB foam is 3. 19%, the axial direction density of the foam is uniform which indicates none evident settlement of gold nanoparticles. SEM tests show that the gold doped DVB polymer foams have open-celled structure and very uniform aperture, and the average pore size is about 1 μm, which is much smaller than that of pure DVB foams. EDX test shows that Au disperses uniformly in the foams. (authors)

  14. Recovery of carrier-free gold-195

    International Nuclear Information System (INIS)

    Iofa, B.Z.; Ivanova, N.A.

    1995-01-01

    It is known that gold(III) is readily extracted from nitric acid solutions with ethers. The authors have studied extraction of trace amounts of gold(III) from nitric acid solutions with diethyl and diisopropyl ethers in the presence of significant excess of Pt(IV). Distribution coefficients of gold(III) were measured radiometrically using carrier-free gold-195 or spectrophotometrically in the presence of platinum(IV). Very high coefficients of gold separation from platinum may be achieved. Preliminary experiments have shown that zinc-65 was not extracted with ethers from nitric acid solutions. As an extraction system, the authors have chosen the system 10 M HNO 3 -diisopropyl ether. After model experiments, the authors have performed recovery of carrier-free gold-195 from a real platinum target irradiated with protons in a cyclotron

  15. Metallic gold beads in hyaluronic acid

    DEFF Research Database (Denmark)

    Pedersen, Dan Sonne; Tran, Thao Phuong; Smidt, Kamille

    2013-01-01

    Multiple sclerosis (MS) is a neurodegenerative disease caused by recurring attacks of neuroinflammation leading to neuronal death. Immune-suppressing gold salts are used for treating connective tissue diseases; however, side effects occur from systemic spread of gold ions. This is limited...... by exploiting macrophage-induced liberation of gold ions (dissolucytosis) from gold surfaces. Injecting gold beads in hyaluronic acid (HA) as a vehicle into the cavities of the brain can delay clinical signs of disease progression in the MS model, experimental autoimmune encephalitis (EAE). This study...... investigates the anti-inflammatory properties of metallic gold/HA on the gene expression of tumor necrosis factor (Tnf-α), Interleukin (Il)-1β, Il-6, Il-10, Colony-stimulating factor (Csf)-v2, Metallothionein (Mt)-1/2, Bcl-2 associated X protein (Bax) and B cell lymphoma (Bcl)-2 in cultured J774 macrophages...

  16. Physiological investigation of gold nanorods toward watermelon.

    Science.gov (United States)

    Wan, Yujie; Li, Junli; Ren, Hongxuan; Huang, Jin; Yuan, Hong

    2014-08-01

    The objective of the present study was to evaluate the phytotoxicity and oxidant stress of the gold nanorods toward watermelon, and hence give a quantitative risk assessment of both seeds and plants phase. The seed germination, the activity of antioxidant enzymes, and the contents of soluble protein and malondialdehyde (MDA) have been measured while the plant roots were observed by transmission electron microscopy (TEM). It was found that the gold nanorods significantly promoted the root elongation. Furthermore, the results on the enzymes activities of plant indicated that oxidative stress happened in the plant treated with gold nanorods. However, the gold nanorods resulted in the phytotoxicity toward plant especially at high concentration. The TEM images of the plant roots with and without the treatment of gold nanorods showed the significant different size of starch granules. In conclusion, significant physiological changes of plant occurred after treatment with the gold nanorods.

  17. The NASA GOLD Mission: Exploring the Interface between Earth and Space

    Science.gov (United States)

    Mason, T.; Costanza, B.

    2017-12-01

    NASA's Global-scale Observations of the Limb and Disk, or GOLD, mission will explore a little understood area close to home, but historically hard to observe: the interface between Earth and space, a dynamic area of near-Earth space that responds both to space weather above, and the lower atmosphere below. GOLD, scheduled to launch into geostationary orbit in early 2018, will collect observations with a 30-minute cadence, much higher than any mission that has come before it. This will enable GOLD to be the first mission to study the day-to-day weather of a region of space—the thermosphere and ionosphere—rather than its long-term climate. GOLD will explore the near-Earth space environment, which is home to astronauts, radio signals used to guide airplanes and ships, and satellites that provide our communications and GPS systems. GOLD's unprecedented images and data will enable research that can improve situational awareness to help protect astronauts, spacecraft, and humans on the ground. As part of the GOLD communications and outreach program, the Office of Communications & Outreach at the Laboratory for Atmospheric and Space Physics (LASP) is developing a suite of products and programs to introduce the science of the GOLD mission to a broad range of public audiences, including students, teachers, journalists, social media practitioners, and the wider planetary and Earth science communities. We plan to showcase with this poster some of the tools we are developing to achieve this goal.

  18. El Médico de su Honra (The Doctor of his Own Honor by Calderón de la Barca: The Honor as a Cause of Exemption of the Penal Responsibility in the Baroque Spain

    Directory of Open Access Journals (Sweden)

    José Palacio González

    2014-12-01

    Full Text Available The notion of honor or reputation is at the very core of the Spanish theatre in the baroque period. This fact could not be correctly understood without taking into consideration the obsession about purity of blood, having got a relevant influence in the Spanish society daily life since the expulsion of the Jewish population and the taking over of Grenade in 1492, as well as the first rank role played by the clerical and political power against the reform movement into the Church. One additional element that should be included into this general frame of reference is the structural inability of the Spanish economy to take off, after the end of the middle-age, in a process leading to a beginning of industrial revolution, with the subsequent assumption of modern values that necessarily would come out of that process. The most telling example of the importance of the idea of honor in the Spanish baroque theatre is, with no doubt, The Doctor of his own honor (El medico de su honra, by Calderón de la Barca, which plot turns around the announced death of an innocent lady suspicioned of adultery, just because of an unhappy sets of events. In the play the jealousy is less determinant for the purpose of the plot that the need for the husband to eliminate any element of uncertainty, as far as his reputation is concerned. The King understands the husband’s motivation and forgives him. Such a conception of honor has left, till very recent times, a major mark in the evolution of the Spanish society, even at a legislative level. El concepto de honor o reputación es un elemento fundamental en el teatro barroco español. Este hecho no se puede entender correctamente sin tener en cuenta la obsesión por la pureza de sangre, concepto con una influencia relevante en la vida cotidiana de la sociedad española desde la expulsión de la población judía y la conquista de Granada en 1492, así como por el papel fundamental desempeñado por el poder clerical y pol

  19. Glyco-gold nanoparticles: synthesis and applications

    OpenAIRE

    Compostella, Federica; Pitirollo, Olimpia; Silvestri, Alessandro; Polito, Laura

    2017-01-01

    Glyco-gold nanoparticles combine in a single entity the peculiar properties of gold nanoparticles with the biological activity of carbohydrates. The result is an exciting nanosystem, able to mimic the natural multivalent presentation of saccharide moieties and to exploit the peculiar optical properties of the metallic core. In this review, we present recent advances on glyco-gold nanoparticle applications in different biological fields, highlighting the key parameters which inspire the glyco ...

  20. Glyco-gold nanoparticles: synthesis and applications

    Directory of Open Access Journals (Sweden)

    Federica Compostella

    2017-05-01

    Full Text Available Glyco-gold nanoparticles combine in a single entity the peculiar properties of gold nanoparticles with the biological activity of carbohydrates. The result is an exciting nanosystem, able to mimic the natural multivalent presentation of saccharide moieties and to exploit the peculiar optical properties of the metallic core. In this review, we present recent advances on glyco-gold nanoparticle applications in different biological fields, highlighting the key parameters which inspire the glyco nanoparticle design.

  1. Gold, fiat money and price stability

    OpenAIRE

    Michael D. Bordo; Robert Dittmar; William T. Gavin

    2006-01-01

    The classical gold standard has long been associated with long-run price stability. But short-run price variability led critics of the gold standard to propose reforms that look much like modern versions of price-path targeting. This paper uses a dynamic stochastic general equilibrium model to examine price dynamics under alternative policy regimes. In the model, an inflation target provides more short-run price stability than does the gold standard and, although it introduces a unit root int...

  2. Gold and Silver Extraction from Leach Solutions

    Directory of Open Access Journals (Sweden)

    Bagdaulet K. Kenzhaliyev

    2014-03-01

    Full Text Available There has been carried out an investigation on the extraction of gold and silver from thiosulfate solutions: standard test and technological solutions of chemical and electrochemical leaching. The influence of related metals on the process of extracting gold from solution was studied. There has been conducted a comparative study of the IR spectra of solutions after the sorption of gold, silver and related metals.

  3. Shape-Controlled Gold Nanoparticle Synthesis

    Science.gov (United States)

    2013-09-01

    Shankar, S. S.; Bhargava, S.; Sastry, M. Synthesis of Gold Nanospheres and Nanotriangles by the Turkevich Approach. Journal of Nanoscience and...Accounts of Chemical Research 2008, 41, 1587–1595. 22. Sun, Y.; Xia, Y. Shape-Controlled Synthesis of Gold And Silver Nanoparticles. Science...N.; Griep, M. H.; and Karna, S. P. Chemical vs. Sonochemical Synthesis and Characterization of Silver , Gold, and Hybrid Nanoparticles; ARL-TR-5764

  4. Methods to reduce mercury pollution is small gold mining operations

    International Nuclear Information System (INIS)

    Pantoja-Timaran, F.; Alvarez-Rodriguez, R.; Rodriguez-Avello, A. S.

    2005-01-01

    The use of mercury for gold beneficiation is still a current practice in small mining operations, mainly in underdeveloped countries, due to the low investment required and necessity of easy to operate systems. But the lack of basic protections makes unavoidable the high pollution of water streams, soils, and in fact, human bodies. some improvements have been done at site like that related to the removal of the mercury from the amalgam, that usually was done in the open air, and now have been changed to the utilization of artisan iron retorts which considerable reduce the emissions of mercury vapors to the atmosphere, but there are still high losses of mercury into the waste solids or tailings coming from the amalgamation process (nearly most of the total weight of the ore treated). In order to reduce the mercury losses into the tailings from the process, this research work has been based in the use of cheap systems, available to the isolated miners, to proof that it is feasible to get an important reduction of the losses and the pollution. the procedure has been accomplished by means of washing the ores with alkaline or detergent agents, together with the use of activated mercury purified by electrowinning in a simple device, easily manufactured in site by the own workers. It is also proven herewith that controlling the time of amalgamation and the total amount of mercury used could reduce the total pollution, and in addition, the gold recovery would be improved. This investigation reports the possibility of a reduction of mercury losses down to 2.4 g per 100 of gold produced (case of rich ores like LaBruja), with gold recovery up to 94%; and 8,6 g per 100 g of gold produced (from ores with average grades like La Gruesa), and gold recoveries in the range of 92%. All that is about 20 to 100 times lower than data reported in current bibliography. The introduction of a previous step of the ore concentration in shaking tables, decreases the total amount of solids for

  5. Uptake, translocation, and toxicity of gold nanorods in maize

    Science.gov (United States)

    Moradi Shahmansouri, Nastaran

    Nanomaterials are widely used in many different products, such as electronics, cosmetics, industrial goods, biomedical uses, and other material applications. The heavy emission of nanomaterials into the environment has motived increasing concern regarding the effects on ecosystems, food chains, and, human health. Plants can tolerate a certain amount of natural nanomaterials, but large amounts of ENMs released from a variety of industries could be toxic to plants and possibly threaten the ecosystem. Employing phytoremediation as a contamination treatment method may show promise. However a pre-requisite to successful treatment is a better understanding of the behavior and effects of nanomaterials within plant systems. This study is designed to investigate the uptake, translocation, bioavailability, and toxicity of gold nanorods in maize plants. Maize is an important food and feed crop that can be used to understand the potential hazardous effects of nanoparticle uptake and distribution in the food chain. The findings could be an important contribution to the fields of phytoremediation, agri-nanotechnology, and nanoparticle toxicity on plants. In the first experiment, hydroponically grown maize seedlings were exposed to similar doses of commercial non-coated gold nanorods in three sizes, 10x34 nm, 20x75 nm, and 40x96 nm. The three nanorod species were suspended in solutions at concentrations of 350 mg/l, 5.8 mg/l, and 14 mg/l, respectively. Maize plants were exposed to all three solutions resulting in considerably lower transpiration and wet biomass than control plants. Likewise, dry biomass was reduced, but the effect is less pronounced than that of transpiration and wet biomass. The reduced transpiration and water content, which eventually proved fatal to exposed plants, were most likely a result of toxic effect of gold nanorod, which appeared to physically hinder the root system. TEM images proved that maize plants can uptake gold particles and accumulate them in

  6. La transdisciplina hecha práctica: El Programa Honor de Estudios Ambientales y Desarrollo Humano Sostenible de la Universidad Austral de Chile

    Directory of Open Access Journals (Sweden)

    Juan Carlos Skewes V.

    2007-12-01

    Full Text Available Resumen La UACh ha propuesto, a través del CEAM, el Programa de Honor en Estudios Ambientales, el cual, de inspiración transdisciplinaria, establece una nueva experiencia formativa para estudiantes, profesoras y profesores, y no académicos, experiencia fundada en una concepción de co-partícipes protagónicos que, sobre la base de sus proyecciones al entorno regional, procuran acceder a nuevas formas de entendimiento y acción. La asignatura, Filosofías del Desarrollo, se incubo esta idea, abriéndose a una comunidad indígena. Cada equipo de alumnos y alumnas catalogó y sistematizó proyectos demostrativos de gestión comunitaria chilenos considerados exitosos, los que se someten a la discusión del grupo curso al tanto que la comunidad escogida evaluó los trabajos sobre la base de su contribución a solucionar sus problemas. Palabras-llave: Gestión Comunitaria; Transdisciplinaridad; Excelencia en Enseñanza Superior; Ecossocioeconomia Abstract At the UACH, an interdisciplinary group of scholars linked to environmental studies put forward a pilot project for implementing a new experience in higher education. We aim to provide a summary of what this experience has meant, using the most recent class as an example. Some background about the university and the Chilean system needs to be supplied, while most of the paper deals with the particular features of this program and its immediate future. This paper describes the honors experience at the UACh. The UACh program is of interest not only because of its Latin American context, but also because it is focused on a particular theme, Environmental Studies and Sustainable Human Development. After three years, the program has just completed its pilot phase, and so the time is appropriate to describe its accomplishments and challenges. Key-Words: Communitarian Management; Transdisciplinary; Higher Education; Ecosocioeconomics “El crecimiento de los saberes, sin precedente en la historia

  7. Coal gold agglomeration: an innovative approach to the recovery of gold in environmentally sensitive areas

    Energy Technology Data Exchange (ETDEWEB)

    Wall, N.C.; Hughes-Narborough, C.; Willey, G. [Davy (Stockton) Ltd., Stockton-on-Tees (United Kingdom)

    1994-11-01

    Coal Gold Agglomeration (CGA) was developed by BP Minerals and involves the selective recovery of oleophilic gold particles from an aqueous slurry into coal-oil agglomerates. These agglomerates are allowed to build up to a high gold loading and are then separated from the slurry. The loaded agglomerates are burned and the gold is finally recovered from the ash residue by dissolution and precipitation or by direct smelting. 6 figs.

  8. Chemistry of Oligonucleotibe-Gold Nanoparticle Conjugates

    National Research Council Canada - National Science Library

    Letsinger, Robert

    2003-01-01

    Conjugates prepared by immobilizing thiol-terminated oligonucleotides onto gold nanoparticles from stable colloidal solutions in aqueous media The oligo nucleotides can serve as linkers to organize...

  9. Gold nano-particles fixed on glass

    International Nuclear Information System (INIS)

    Worsch, Christian; Wisniewski, Wolfgang; Kracker, Michael; Rüssel, Christian

    2012-01-01

    Highlights: ► We produced wear resistant gold–ruby coatings on amorphous substrates. ► Thin sputtered gold layers were covered by or embedded in silica coatings. ► Annealing above T g of the substrate glass led to the formation of gold nano particles. ► A 1 1 1-texture of the gold particles is observed via XRD and EBSD. ► EBSD-patterns can be acquired from crystals covered by a thin layer of glass. - Abstract: A simple process for producing wear resistant gold nano-particle coatings on transparent substrates is proposed. Soda-lime-silica glasses were sputtered with gold and subsequently coated with SiO 2 using a combustion chemical vapor deposition technique. Some samples were first coated with silica, sputtered with gold and then coated with a second layer of silica. The samples were annealed for 20 min at either 550 or 600 °C. This resulted in the formation of round, well separated gold nano-particles with sizes from 15 to 200 nm. The color of the coated glass was equivalent to that of gold–ruby glasses. Silica/gold/silica coatings annealed at 600 °C for 20 min were strongly adherent and scratch resistant. X-ray diffraction and electron backscatter diffraction (EBSD) were used to describe the crystal orientations of the embedded particles. The gold particles are preferably oriented with their (1 1 1) planes perpendicular to the surface.

  10. CO oxidation on gold nanoparticles: Theoretical studies

    DEFF Research Database (Denmark)

    Remediakis, Ioannis; Lopez, Nuria; Nørskov, Jens Kehlet

    2005-01-01

    We present a summary of our theoretical results regarding CO oxidation on both oxide-supported and isolated gold nanoparticles. Using Density Functional Theory we have studied the adsorption of molecules and the oxidation reaction of CO on gold clusters. Low-coordinated sites on the gold...... nanoparticles can adsorb small inorganic molecules such as O2 and CO, and the presence of these sites is the key factor for the catalytic properties of supported gold nanoclusters. Other contributions, induced by the presence of the support, can provide parallel channels for the reaction and modulate the final...

  11. Gold Rushes and mineral property rights allocation

    DEFF Research Database (Denmark)

    Sinding, Knud

    , is to handle the other projects that are generated by the "gold rush" informational externalities created by the initial discovery. At the core of the problems of dealing with a gold rush situation is both the informational externality and an institutional framework which is not designed to deal with large...... influxes of prospectors competing for a very limited area. This paper charts significant gold rush events in the mineral industry in recent decades and uses preliminary data on the areas impacted by these gold rushes to argue that many mineral tenure systems should be modified in order to be better able...

  12. Gold Cleaning Methods for Electrochemical Detection Applications

    DEFF Research Database (Denmark)

    Fischer, Lee MacKenzie; Tenje, Maria; Heiskanen, Arto

    2009-01-01

    This work investigates methods for obtaining reliably clean gold film surfaces. Nine gold cleaning methods are investigated here: UV ozone photoreactor; potassium hydroxide-hydrogen peroxide; potassium hydroxide potential sweep; sulfuric acid hydrogen peroxide; sulfuric acid potential cycling......-ray photo-electron spectroscopy are used to characterize surface cleanliness. A low peak-current potential-difference and charge transfer resistance indicates a cleaner surface, as does a higher percentage of elemental gold on the electrode surface. The potassium hydroxide potential sweep method is found...... to leave the gold surface the cleanest overall....

  13. Validating Automated Essay Scoring: A (Modest) Refinement of the "Gold Standard"

    Science.gov (United States)

    Powers, Donald E.; Escoffery, David S.; Duchnowski, Matthew P.

    2015-01-01

    By far, the most frequently used method of validating (the interpretation and use of) automated essay scores has been to compare them with scores awarded by human raters. Although this practice is questionable, human-machine agreement is still often regarded as the "gold standard." Our objective was to refine this model and apply it to…

  14. Honor and Reputation: Some Issues of Improvement of a Conceptual Framework in the Sphere of Protection of the Personal Non-Property Rights

    Directory of Open Access Journals (Sweden)

    Loos Evgenii V.

    2018-03-01

    Full Text Available The article is about the question of terminology improvement in the field of providing rights of defense of human honor and dignity. The Author analyzes some legal terms that have been set in the legislation, touches an issue of their interpretation. Noting that the concepts “honor”, “good name” and “reputation” are synonyms, he asks about expediency of fixing in the legislation several concepts having identical value. Proving the point of his view, the Author considers that the concepts “honor”, “good name” and “business reputation” can be replaced with the unified term “reputation”. The Author offers to discuss the statement of the following articles of the specified acts: p. 1 Art. 23 of the Constitution of the Russian Federation, p. 1 Art. 128.1 of the Criminal Code of the Russian Federation, Art. 152 of the Civil Code of the Russian Federation, p. 1 Art. 5.61 of the Code of the Russian Federation of Administrative Offences.

  15. Colloidal gold probe based rapid immunochromatographic strip assay for cortisol

    Energy Technology Data Exchange (ETDEWEB)

    Nara, Seema, E-mail: seemanara@mnnit.ac.in [Department of Applied Mechanics (Biotechnology), Motilal Nehru National Institute of Technology, Allahabad 211004 (India); Department of Reproductive Biomedicine, National Institute of Health and Family Welfare, Munirka, New Delhi 110067 (India); Center for BioMedical Engineering, Indian Institute of Technology, New Delhi 110016 (India); Tripathi, Vinay [Department of Reproductive Biomedicine, National Institute of Health and Family Welfare, Munirka, New Delhi 110067 (India); Center for BioMedical Engineering, Indian Institute of Technology, New Delhi 110016 (India); Singh, Harpal [Center for BioMedical Engineering, Indian Institute of Technology, New Delhi 110016 (India); Shrivastav, Tulsidas G. [Department of Reproductive Biomedicine, National Institute of Health and Family Welfare, Munirka, New Delhi 110067 (India)

    2010-12-03

    A rapid and semi-quantitative immunochromatographic strip (ICS) test for cortisol analysis in serum was developed. The test strip was based on a competitive assay format. Colloidal gold nanoparticles were synthesized and coupled with cortisol-3-carboxymethyloxime-adipic acid dihydrazide-bovine serum albumin (F-3-CMO-ADH-BSA) antigen to directly compete with cortisol in human serum samples. F-3-CMO-ADH-BSA-gold label and uncoupled colloidal gold nanoparticles were appropriately characterized using UV-vis spectroscopy, transmission electron microscopy and atomic force microscopy. Anticortisol antibody raised against F-3-CMO-BSA immunogen in New Zealand white rabbits was coated on the NC membrane as test line. Anti-BSA antibody was used as control line. The lower detection limit of the ICS test was 30 ng mL{sup -1} with visual detection and was completed in 10 min. About 30 human serum samples were also analyzed by the developed strip test and their range of cortisol concentration was established. The developed ICS test is rapid, economic and user friendly.

  16. Nuclear excitation in muonic gold

    CERN Document Server

    Robert Tissot, B; Debrunner, P; Engfer, R; Link, R; Schellenberg, L; Schneuwly, H; Walter, H K

    1973-01-01

    Energies and intensities of muonic X-rays in gold were measured at the CERN muon channel with an experimental set-up as described by Backe et al. (1972). The 2p-1s and 3d-2p transitions could only be analysed taking into account beside the static quadrupole interaction a dynamical hyperfine interaction of the 2p states, which leads to an excitation of the first four nuclear levels. The dynamical hyperfine interaction was calculated using the core excitation model (de Shalit, (1961)). (0 refs).

  17. Paper-based tuberculosis diagnostic devices with colorimetric gold nanoparticles

    International Nuclear Information System (INIS)

    Tsai, Tsung-Ting; Shen, Shu-Wei; Chen, Chien-Fu; Cheng, Chao-Min

    2013-01-01

    A colorimetric sensing strategy employing gold nanoparticles and a paper assay platform has been developed for tuberculosis diagnosis. Unmodified gold nanoparticles and single-stranded detection oligonucleotides are used to achieve rapid diagnosis without complicated and time-consuming thiolated or other surface-modified probe preparation processes. To eliminate the use of sophisticated equipment for data analysis, the color variance for multiple detection results was simultaneously collected and concentrated on cellulose paper with the data readout transmitted for cloud computing via a smartphone. The results show that the 2.6 nM tuberculosis mycobacterium target sequences extracted from patients can easily be detected, and the turnaround time after the human DNA is extracted from clinical samples was approximately 1 h. (paper)

  18. Metallogeny of gold in the Fennoscandian Shield

    Science.gov (United States)

    Gaál, G.; Sundblad, K.

    1990-12-01

    Gold occurs in a number of different ore types in the Fennoscandian Shield ranging in age from Late Archean to Late Proterozoic. Until recently, the metal was exploited primarily as a byproduct in volcanogenic massive sulphide deposits but during the 1980s more gold mines have been opened than during any other episode in the mining history of northern Europe. The occurrence of gold in the Fennoscandian Shield is reviewed in the context of the major tectonostratigraphic units: 1. In the Karelian Province, gold is hosted by greenstone belts of the Archean basement complex e.g. at Ilomantsi, eastern Finland. Greenstone belts of the Nordkalott Province, which are interpreted as part of an Early Proterozoic cover sequence, contain gold deposits associated with copper (Bidjovagge, Saattopora and Pahtohavare). Gold is also associated with cobalt in the metasomatically altered Early Proterozoic cover in north-eastern Finland (Meurastuksenaho and Juomasuo). 2. In the Svecofennian Domain, the major gold deposits were generated during the emplacement of 1.92 1.87 Ga old accretional magmatism. These deposits occur in the northeastern part of the Svecofennian Domain, close to the Archean-Proterozoic boundary. They comprise two major types: (a) the porphyry-type and shear-zone gold hosted by tonalite at Tallberg, Laivakangas, Kopsa and Osikonmäki; (b) as a component of volcanogenic massive sulphide deposits (e.g. Holmtjärn, Boliden and Pyhäsalmi). Other types are: (c) gold-bearing quartz-alumina alteration zones formed during the 1.92 1.87 Ga magmatic period (Enåsen); (d) gold in massive sulphide and iron ore deposits in Bergslagen. 3. Gold associated with 1.84 1.54 Ga granites has been reported from several sites in the Shield, including quartz veins and contact-metasomatic deposits. In addition, shear-zone-related gold deposits post-dating these granites have been identified in southeastern Sweden (Ädelfors). 4. In the Sveconorwegian Domain, the gold deposits at Bleka

  19. Geochemical methodology for gold prospect ion in Uruguay

    International Nuclear Information System (INIS)

    Spangenber, J.

    1987-01-01

    This work is about the history of gold prospection in Uruguay. In this study there are considered the geochemical aspects, the gold performance, the applicability to mining prospection and the gold prospection aluvionar

  20. Gold emissivities for hydrocode applications

    International Nuclear Information System (INIS)

    Bowen, C.; Wagon, F.; Galmiche, D.; Loiseau, P.; Dattolo, E.; Babonneau, D.

    2004-01-01

    The Radiom model [M. Busquet, Phys Fluids B 5, 4191 (1993)] is designed to provide a radiative-hydrodynamic code with non-local thermodynamic equilibrium (non-LTE) data efficiently by using LTE tables. Comparison with benchmark data [M. Klapisch and A. Bar-Shalom, J. Quant. Spectrosc. Radiat. Transf. 58, 687 (1997)] has shown Radiom to be inaccurate far from LTE and for heavy ions. In particular, the emissivity was found to be strongly underestimated. A recent algorithm, Gondor [C. Bowen and P. Kaiser, J. Quant. Spectrosc. Radiat. Transf. 81, 85 (2003)], was introduced to improve the gold non-LTE ionization and corresponding opacity. It relies on fitting the collisional ionization rate to reproduce benchmark data given by the Averroes superconfiguration code [O. Peyrusse, J. Phys. B 33, 4303 (2000)]. Gondor is extended here to gold emissivity calculations, with two simple modifications of the two-level atom line source function used by Radiom: (a) a larger collisional excitation rate and (b) the addition of a Planckian source term, fitted to spectrally integrated Averroes emissivity data. This approach improves the agreement between experiments and hydrodynamic simulations

  1. Paper Money but a Gold Debt. Italy in the Gold Standard

    OpenAIRE

    Giuseppe Tattara; or consequences)

    2002-01-01

    During the 52 years between the Unification of the Kingdom of Italy and World War 1, the lira was legally convertible into metal for a limited period of time. Although not formally committed to gold, the lira exchange towards the gold standard countries proved remarkably stable, \\223shadowing\\224 gold. It is widely claimed that being one of the successful members of the gold standard circle entailed a number of advantages. If the lira was closely linked to gold, suggesting that there was only...

  2. Lamellar multilayer hexadecylaniline-modified gold nanoparticle ...

    Indian Academy of Sciences (India)

    Materials Chemistry Division, National Chemical Laboratory, Pune 411 008,. India e-mail: ... to the Brust method for the synthesis of hydrophobized gold nanoparticles.33 This process essentially consists of .... due to rearrangement of the gold nanoparticles within domains (and reorganization of the domains themselves) on ...

  3. Dress Images on Gold-foil Figures

    DEFF Research Database (Denmark)

    Mannering, Ulla; Andersson Strand, Eva Birgitta

    2009-01-01

    From the Late Iron Age settlement Sorte Muld on Bornholm both gold foil figures with depictions of costumes and textile tools can tell about textile production.......From the Late Iron Age settlement Sorte Muld on Bornholm both gold foil figures with depictions of costumes and textile tools can tell about textile production....

  4. Nonlinear optical studies of single gold nanoparticles

    NARCIS (Netherlands)

    Dijk, Meindert Alexander van

    2007-01-01

    Gold nanoparticles are spherical clusters of gold atoms, with diameters typically between 1 and 100 nanometers. The applications of these particles are rather diverse, from optical labels for biological experiments to data carrier for optical data storage. The goal of my project was to develop new

  5. Computational approaches to homogeneous gold catalysis.

    Science.gov (United States)

    Faza, Olalla Nieto; López, Carlos Silva

    2015-01-01

    Homogenous gold catalysis has been exploding for the last decade at an outstanding pace. The best described reactivity of Au(I) and Au(III) species is based on gold's properties as a soft Lewis acid, but new reactivity patterns have recently emerged which further expand the range of transformations achievable using gold catalysis, with examples of dual gold activation, hydrogenation reactions, or Au(I)/Au(III) catalytic cycles.In this scenario, to develop fully all these new possibilities, the use of computational tools to understand at an atomistic level of detail the complete role of gold as a catalyst is unavoidable. In this work we aim to provide a comprehensive review of the available benchmark works on methodological options to study homogenous gold catalysis in the hope that this effort can help guide the choice of method in future mechanistic studies involving gold complexes. This is relevant because a representative number of current mechanistic studies still use methods which have been reported as inappropriate and dangerously inaccurate for this chemistry.Together with this, we describe a number of recent mechanistic studies where computational chemistry has provided relevant insights into non-conventional reaction paths, unexpected selectivities or novel reactivity, which illustrate the complexity behind gold-mediated organic chemistry.

  6. Geochemistry of hydrothermal gold deposits: A review

    Directory of Open Access Journals (Sweden)

    Yongfeng Zhu

    2011-07-01

    Full Text Available Mineral assemblages formed during hydrothermal alteration reflect the geochemical composition of ore-forming fluids. Gold is mainly transported in solution as Au–Cl and Au–S complexes. The change of physicochemical conditions such as temperature, pressure, oxygen fugacity, and sulfur fugacity are effective mechanisms for gold precipitation. Gold tends to be concentrated in the vapor phase of fluids at high temperatures and pressures. Au–As and Au–Sb associations are common in gold deposit. Native antimony and/or arsenic – native gold assemblages may precipitate from hydrothermal fluids with low sulfur fugacity. Hydrothermal fluids forming epithermal gold deposits are Au-saturated in most cases, whereas fluids of Carlin-type are Au-undersaturated. Quasi-steady As-bearing pyrite extracts solid solution Au from hydrothermal fluids through absorption. The capability of As-bearing pyrite to absorb Au from under-saturated fluid is the key to the formation of large-scale Carlin-type deposits. With increasing new data, studies on the geochemistry of gold deposits can be used to trace the origin of ore-forming fluids, the source of gold, and the transporting form of Au and other ore-forming elements, such as Si, S, F, Cl, As and Ag.

  7. Goudafzettingen in Suriname (Gold deposits in Surinam)

    NARCIS (Netherlands)

    Brinck, J.W.

    1956-01-01

    THE GOLD DEPOSITS IN SURINAM AND THE DISTRIBUTION OF CONCESSIONS THROUGH THE COUNTRY The fieldwork on the occurrence of primary and secondary gold deposits in Surinam on which this thesis is based was carried out by order of the Welfare Fund Surinam (Welvaarts Fonds Suriname) during the periods

  8. Numerical simulations of nanostructured gold films

    DEFF Research Database (Denmark)

    Repän, Taavi; Frydendahl, Christian; Novikov, Sergey M.

    2017-01-01

    We present an approach to analyse near-field effects on nanostructured gold films by finite element simulations. The studied samples are formed by fabricating gold films near the percolation threshold and then applying laser damage. Resulting samples have complicated structures, which...

  9. Spherical aggregates composed of gold nanoparticles

    International Nuclear Information System (INIS)

    Chen, C-C; Kuo, P-L; Cheng, Y-C

    2009-01-01

    Alkylated triethylenetetramine (C12E3) was synthesized and used as both a reductant in the preparation of gold nanoparticles by the reduction of HAuCl 4 and a stabilizer in the subsequent self-assembly of the gold nanoparticles. In acidic aqueous solution, spherical aggregates (with a diameter of about 202 ± 22 nm) of gold nanoparticles (with the mean diameter of ∼18.7 nm) were formed. The anion-induced ammonium adsorption of the alkylated amines on the gold nanoparticles was considered to provide the electrostatic repulsion and steric hindrance between the gold nanoparticles, which constituted the barrier that prevented the individual particles from coagulating. However, as the amino groups became deprotonated with increasing pH, the ammonium adsorption was weakened, and the amino groups were desorbed from the gold surface, resulting in discrete gold particles. The results indicate that the morphology of the reduced gold nanoparticles is controllable through pH-'tunable' aggregation under the mediation of the amino groups of alkylated amine to create spherical microstructures.

  10. Gold 100: proceedings of the international conference on gold. V. 2

    International Nuclear Information System (INIS)

    Fivaz, C.E.; King, R.P.

    1986-01-01

    The proceedings of Gold 100 have been published in three separate volumes. The first deals with the mining of gold, the second with the extractive metallurgy of gold, and the third with industrial uses of gold. In this second volume, the papers on extractive metallurgy presented at the Conference reflect most of the problems that are currently of significant technical interest to the industry. This volume is divided in six main parts covering plant design, carbon-in-pulp technology, refractory gold, new technology, grinding and concentration, and leaching. The part on new technology includes papers on x-ray fluorescence analyzers, Moessbauer spectroscopy and leaching processes for uranium, while the part on grinding and concentration includes papers on nuclear and radiotracer techniques for the recovery of gold as well as various flotation parameters in the flotation behaviour of gold and uranium

  11. Synthesis of camptothecin-loaded gold nanomaterials

    International Nuclear Information System (INIS)

    Xing Zhimin; Liu Zhiguo; Zu Yuangang; Fu Yujie; Zhao Chunjian; Zhao Xiuhua; Meng Ronghua; Tan Shengnan

    2010-01-01

    Camptothecin-loaded gold nanomaterials have been synthesized by the sodium borohydride reduction method under a strong basic condition. The obtained gold nanomaterials have been characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM) and UV-vis absorption spectroscopy. The camptothecin-loaded gold colloidal solution was very stable and can be stored for more than two months at room temperature without obvious changes. The color of the colloidal solution can change from wine red to purple and blue during the acidifying process. It was revealed that the release of camptothecin and the aggregation of gold nanoparticles can be controlled by tuning the solution pH. The present study implied that the gold nanomaterials can be used as the potential carrier for CPT delivery.

  12. Optical constant of thin gold films

    DEFF Research Database (Denmark)

    Yakubovsky, D. I.; Fedyanin, D. Yu; Arsenin, A. V.

    2017-01-01

    The performance of metal-based devices is limited by ohmic losses in the metal, which are determined by electron scattering. The structural properties of gold thin films also play an important role in the film quality, which may affect its' optical properties and the overall capability of the dev......The performance of metal-based devices is limited by ohmic losses in the metal, which are determined by electron scattering. The structural properties of gold thin films also play an important role in the film quality, which may affect its' optical properties and the overall capability...... and spectroscopic ellipsometry, the structural morphology and optical properties of polycrystalline gold thin films (fabricated by e-beam deposition at a low sputtering rate smooth gold) in the thickness range of 20 - 200 nm. By extracting the real and imaginary dielectric function and the Drude parameter...... predicts optical losses based on structure of the gold films....

  13. The interaction of gold with gallium arsenide

    Science.gov (United States)

    Weizer, Victor G.; Fatemi, Navid S.

    1988-01-01

    Gold and gold-based alloys, commonly used as solar-cell contact materials, are known to react readily with gallium arsenide. Experiments designed to identify the mechanisms involved in these GaAs-metal interactions have yielded several interesting results. It is shown that the reaction of GaAs with gold takes place via a dissociative diffusion process. It is shown further that the GaAs-metal reaction rate is controlled to a very great extent by the condition of the free surface of the contact metal, an interesting example of which is the previously unexplained increase in the reaction rate that has been observed for samples annealed in a vacuum environment as compared to those annealed in a gaseous ambient. A number of other hard-to-explain observations, such as the low-temperature formation of voids in the gold lattice and crystallite growth on the gold surface, are also explained by invoking this mechanism.

  14. Gold analysis by the gamma absorption technique

    International Nuclear Information System (INIS)

    Kurtoglu, Arzu; Tugrul, A.B.

    2003-01-01

    Gold (Au) analyses are generally performed using destructive techniques. In this study, the Gamma Absorption Technique has been employed for gold analysis. A series of different gold alloys of known gold content were analysed and a calibration curve was obtained. This curve was then used for the analysis of unknown samples. Gold analyses can be made non-destructively, easily and quickly by the gamma absorption technique. The mass attenuation coefficients of the alloys were measured around the K-shell absorption edge of Au. Theoretical mass attenuation coefficient values were obtained using the WinXCom program and comparison of the experimental results with the theoretical values showed generally good and acceptable agreement

  15. Gold Liquid Crystals in the XXI Century

    Directory of Open Access Journals (Sweden)

    Manuel Bardají

    2014-08-01

    Full Text Available Since the first gold liquid crystal was described in 1986, much effort has been done to prepare new compounds bearing this property. The review deals with the last results obtained in this new century. Gold(I has a strong affinity to give linear co-ordination and metal-metal interactions, which produce a rich supramolecular chemistry, and can promote the behavior as liquid crystal. Therefore, most liquid crystals are based on rod-like gold(I compounds, while gold(III liquid crystals are scarce. Calamitic and discotic mesogens have been reported, as well as chiral liquid crystals. Weak interactions such as H-bonds have also been used to obtain gold mesogens. Some of them exhibit additional properties, such as color, luminescence, and chirality. Luminescence has been reported, not only in the solid state or in solution, but also in the mesophase. This is relevant for applications in LEDs (Light Emitting Diodes, information storage, and sensors.

  16. Carbonate hosted gold deposit in Tasmania, Australia

    International Nuclear Information System (INIS)

    Abadi, M.H.

    1999-01-01

    Full text: This study uses elemental and isotopic composition of carbonates associated with gold from Henty and Beaconsfield in Tasmania, Australia, to illustrate source of gold-bearing fluids, salinity, temperature and dissolution and reprecipitation of carbonate. The Beaconsfield and Henty gold mines are located in northern and western Tasmania respectively. Gold mineralisation in Beaconsfield occurs within the quartz-carbonate Tasmania Reef (Lower to Middle Palaeozoic sequence, Hills, 1998). The Henty gold mine is located at the base of the Cambrian Tyndall Group (volcano-sedimentary succession, White and McPhie, 1996) close to Henty Fault. Gold in carbonate samples from Henty ranges from 7.7 to 9360 ppm and in Beaconsfield ranges from 0.01 to 434 ppm. The amount of carbonate in samples from Henty and Beaconsfield gold mines varies from approximately 24 to 99.8%. Bivariate plot of Ca relative to total amounts of Mg, Fe and Mn illustrates that the major carbonate minerals at Beaconsfield and Henty gold mines are magnesian ankerite and calcite. The difference in carbonate mineralogy, at Henty and Beaconsfield gold mines, is attributed to the composition of fluids responsible for carbonate alteration. Gold and magnesium in Beaconsfield ankerite are derived from the leaching of Cambrian ultramafic rocks during the Devonian by the passage of meteoric fluids through tectonically affected Ordovician carbonates (Rao and Adabi, 1999). The total concentration of Fe and Mn are low (0.5 to 2%) in Henty and high (1 to 17.5%) in Beaconsfield ankerite, possibly due to oxidising conditions at Henty and reducing conditions at Beaconsfield gold mines during gold mineralisation. Variation of Sr values between Beaconsfield ankerite and Henty calcite is related to dissolution of limestone that increase Sr concentrations in gold mineralising fluids. Na values in both Beaconsfield (20 to 1100 ppm) and Henty carbonates (25 to 1650 ppm) suggest low salinity fluids responsible for gold

  17. Gold nanoparticles: generation and characterization

    International Nuclear Information System (INIS)

    Dey, G.R.

    2013-07-01

    In this presentation we report the reduction of Au 3+ through chemical and free radical (e solv - ) reactions both in non-aqueous and aqueous media. In chemical reduction, the spectral nature in ascorbic acid (AA) and citric acid (CA) systems was different. The band intensity of gold nanoparticles was lower in AA system. While in free radical reaction, the yield of nanoparticles was pure i.e. free from excess reactants. Under the study 60-200 nm size nanoparticles were generated, which are inert to oxygen. Using pulse radiolysis technique, the initial rate for e solv - reaction with Au 3+ was determined to be 7.6 x 10 9 M -1 s -1 . (author)

  18. Extinction Coefficient of Gold Nanostars.

    Science.gov (United States)

    de Puig, Helena; Tam, Justina O; Yen, Chun-Wan; Gehrke, Lee; Hamad-Schifferli, Kimberly

    2015-07-30

    Gold nanostars (NStars) are highly attractive for biological applications due to their surface chemistry, facile synthesis and optical properties. Here, we synthesize NStars in HEPES buffer at different HEPES/Au ratios, producing NStars of different sizes and shapes, and therefore varying optical properties. We measure the extinction coefficient of the synthesized NStars at their maximum surface plasmon resonances (SPR), which range from 5.7 × 10 8 to 26.8 × 10 8 M -1 cm -1 . Measured values correlate with those obtained from theoretical models of the NStars using the discrete dipole approximation (DDA), which we use to simulate the extinction spectra of the nanostars. Finally, because NStars are typically used in biological applications, we conjugate DNA and antibodies to the NStars and calculate the footprint of the bound biomolecules.

  19. Human Rights and the Rights of Aliens. Working Paper NB-3.

    Science.gov (United States)

    Nickel, James W.

    This paper examines the issue of human rights and the rights of aliens. Contemporary ideas of human rights and contractarian alternatives to universal rights are reviewed. The obligations of governments to admit refugees and to honor the rights of aliens within their borders are discussed. The right to political participation and right to welfare…

  20. Measuring total mercury due to small-scale gold mining activities to determine community vulnerability in Cihonje, Central Java, Indonesia.

    Science.gov (United States)

    Sari, Mega M; Inoue, Takanobu; Matsumoto, Yoshitaka; Yokota, Kuriko

    2016-01-01

    This research is comparative study of gold mining and non-gold mining areas, using four community vulnerability indicators. Vulnerability indicators are exposure degree, contamination rate, chronic, and acute toxicity. Each indicator used different samples, such as wastewater from gold mining process, river water from Tajum river, human hair samples, and health questionnaire. This research used cold vapor atomic absorption spectrometry to determine total mercury concentration. The result showed that concentration of total mercury was 2,420 times than the maximum content of mercury permitted in wastewater based on the Indonesian regulation. Moreover, the mercury concentration in river water reached 685 ng/l, exceeding the quality threshold standards of the World Health Organization (WHO). The mercury concentration in hair samples obtained from the people living in the research location was considered to identify the health quality level of the people or as a chronic toxicity indicator. The highest mercury concentration--i.e. 17 ng/mg, was found in the gold mining respondents. Therefore, based on the total mercury concentration in the four indicators, the community in the gold mining area were more vulnerable to mercury than communities in non-gold mining areas. It was concluded that the community in gold mining area was more vulnerable to mercury contamination than the community in non-gold mining area.

  1. Cyto- and genotoxicity assessment of Gold nanoparticles obtained by laser ablation in A549 lung adenocarcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Bucchianico, Sebastiano Di [Karolinska Institutet, Institute of Environmental Medicine (Sweden); Migliore, Lucia [University of Pisa, Department of Translational Research and New Technologies in Medicine and Surgery, Division of Medical Genetics (Italy); Marsili, Paolo [Institute of Complex Systems (ISC-CNR) (Italy); Vergari, Chiara [Plasma Diagnostics and Technologies s.r.l. (Italy); Giammanco, Francesco [University of Pisa, Department of Physics “E. Fermi” (Italy); Giorgetti, Emilia, E-mail: emilia.giorgetti@fi.isc.cnr.it [Institute of Complex Systems (ISC-CNR) (Italy)

    2015-05-15

    Gold nanoparticles have attracted enormous interest in biomedical applications, based on their unique optical properties. However, their toxicity on human tissues is still an open issue. Beyond the potential intrinsic toxicity of nanostructured gold, a non-negligible contribution of stabilizers or reaction by-products related to current wet chemical synthesis procedures can be expected. Aimed at isolating gold contribution from that of any other contaminant, we produced colloidal suspensions of Gold nanoparticles having average size <10 nm in deionized water or acetone by pulsed laser ablation, that permits preparation of uncoated and highly stable Gold nanoparticles in pure solvents. Subsequently, we investigated the role of surface chemistry, size, and dispersivity of synthesized Gold nanoparticles in exerting toxicity in a cell model system of deep respiratory tract, representing the main route of exposure to NPs, namely adenocarcinoma epithelial A549 cells. Gold nanoparticles prepared in water showed no particular signs of cytotoxicity, cytostasis, and/or genotoxicity as assessed by MTT colorimetric viability test and Cytokinesis-block micronucleus cytome assay up to concentrations of the order of 5 μg/mL. In contrast, Gold nanoparticles produced in pure acetone and then transferred into deionized water showed impaired cell viability, apoptosis responses, micronuclei, and dicentric chromosomes induction as well as nuclear budding, as a function of the amount of surface contaminants like amorphous carbon and enolate ions.

  2. Cyto- and genotoxicity assessment of Gold nanoparticles obtained by laser ablation in A549 lung adenocarcinoma cells

    International Nuclear Information System (INIS)

    Bucchianico, Sebastiano Di; Migliore, Lucia; Marsili, Paolo; Vergari, Chiara; Giammanco, Francesco; Giorgetti, Emilia

    2015-01-01

    Gold nanoparticles have attracted enormous interest in biomedical applications, based on their unique optical properties. However, their toxicity on human tissues is still an open issue. Beyond the potential intrinsic toxicity of nanostructured gold, a non-negligible contribution of stabilizers or reaction by-products related to current wet chemical synthesis procedures can be expected. Aimed at isolating gold contribution from that of any other contaminant, we produced colloidal suspensions of Gold nanoparticles having average size <10 nm in deionized water or acetone by pulsed laser ablation, that permits preparation of uncoated and highly stable Gold nanoparticles in pure solvents. Subsequently, we investigated the role of surface chemistry, size, and dispersivity of synthesized Gold nanoparticles in exerting toxicity in a cell model system of deep respiratory tract, representing the main route of exposure to NPs, namely adenocarcinoma epithelial A549 cells. Gold nanoparticles prepared in water showed no particular signs of cytotoxicity, cytostasis, and/or genotoxicity as assessed by MTT colorimetric viability test and Cytokinesis-block micronucleus cytome assay up to concentrations of the order of 5 μg/mL. In contrast, Gold nanoparticles produced in pure acetone and then transferred into deionized water showed impaired cell viability, apoptosis responses, micronuclei, and dicentric chromosomes induction as well as nuclear budding, as a function of the amount of surface contaminants like amorphous carbon and enolate ions

  3. Advances in complex analysis and operator theory festschrift in honor of Daniel Alpay’s 60th birthday

    CERN Document Server

    Sabadini, Irene; Struppa, Daniele; Vajiac, Mihaela

    2017-01-01

    This book gathers contributions written by Daniel Alpay’s friends and collaborators. Several of the papers were presented at the International Conference on Complex Analysis and Operator Theory held in honor of Professor Alpay’s 60th birthday at Chapman University in November 2016. The main topics covered are complex analysis, operator theory and other areas of mathematics close to Alpay’s primary research interests. The book is recommended for mathematicians from the graduate level on, working in various areas of mathematical analysis, operator theory, infinite dimensional analysis, linear systems, and stochastic processes.

  4. Genetics and the origin of species: the continuing synthesis a symposium in honor of Richard G. Harrison

    Science.gov (United States)

    Grosberg, Richard K.; Rand, David M.; Normark, Benjamin B.

    2013-01-01

    This is a special issue of Genetica that has its origins in a symposium held in honor of Richard G. Harrison at Ithaca, New York on July 22–23. Former students of Rick Harrison organized the symposium and most of the speakers were former students, as well. The quality and breadth of the talks were a testament to Rick’s influence as a thinker, synthesizer, and mentor and it is only appropriate to reflect on Rick’s contributions to the fields of evolutionary ecology, systematics, and genetics in this preface to the symposium articles. PMID:21152955

  5. Health risks of gold miners: a synoptic review

    Science.gov (United States)

    Eisler, R.

    2003-01-01

    Health problems of gold miners who worked underground include decreased life expectancy; increased frequency of cancer of the trachea, bronchus, lung, stomach, and liver; increased frequency of pulmonary tuberculosis (PTB), silicosis, and pleural diseases; increased frequency of insect-borne diseases, such as malaria and dengue fever; noise-induced hearing loss; increased prevalence of certain bacterial and viral diseases; and diseases of the blood, skin, and musculoskeletal system. These problems are briefly documented in gold miners from Australia, North America, South America, and Africa. In general, HIV infection or excessive alcohol and tobacco consumption tended to exacerbate existing health problems. Miners who used elemental mercury to amalgamate and extract gold were heavily contaminated with mercury. Among individuals exposed occupationally, concentrations of mercury in their air, fish diet, hair, urine, blood, and other tissues significantly exceeded all criteria proposed by various national and international regulatory agencies for protection of human health. However, large-scale epidemiological evidence of severe mercury-associated health problems in this cohort was not demonstrable.

  6. Women, mercury and artisanal gold mining : Risk communication and mitigation

    Science.gov (United States)

    Hinton, J. J.; Veiga, M. M.; Beinhoff, C.

    2003-05-01

    Artisanal miners employ rudimentary techniques for minéral extraction and often operate under hazardous, labour intensive, highly disorganized and illegal conditions. Gold is the main mineral extracted by artisanal miners, and the ecological and human health impacts resulting from mercury (Hg) use in gold extraction warrant special consideration. More than 30% of world's 13 million artisanal miners are women and, as they are often perceived to be less suited for labour intensive mining methods, the majority of women work in the processing aspect of artisanal mining, including amalgamation with Hg. As women are also predominantly responsible for food preparation, they are in an excellent position to respond to health risks associated with consumption of Hg-contaminated foods in impacted areas. In addition to their influence on consumption habits, women in artisanal mining communities may be in a position to effect positive change with respect to the technologies employed. Thus, gender sensitive approaches are necessary to reduce exposure risks to women and their families, promote clean technologies and support the development of stronger, healthier artisanal mining communities. This paper describes the roles of women in artisanal gold mining, highlights their importance in reducing the Hg exposure in these communities, and provides insight into how risks from Hg pollution can effectively be communicated and mitigated.

  7. Bioactive gold(i) complexes with 4-mercaptoproline derivatives.

    Science.gov (United States)

    Gutiérrez, Alejandro; Cativiela, Carlos; Laguna, Antonio; Gimeno, M Concepción

    2016-09-14

    Unprecedented gold(i) bioconjugates bearing non-proteinogenic amino acid 4-mercaptoproline species as bioorganic ligands have been prepared. Firstly, the synthesis of Boc-Pro(SH)-OMe (1) has been accomplished by standard procedures. The subsequent reaction of 1 with [AuCl(PR3)] gives complexes Boc-Pro(SAuPR3)-OMe (PR3 = PPh3 (2), PPh2Py (3)). Starting from complex 2 several structural modifications have been performed, in addition to the incorporation of a different phosphine in 3, such as the formation of the acid Boc-Pro(SAuPPh3)-OH (4), the synthesis of a dipeptide derivative by coupling the amino acid glycine tert-butyl ester Boc-Pro(SAuPPh3)-Gly-O(t)Bu (5), or the coordination of another gold phosphine fragment to the sulfur atom as in [Boc-Pro(SAuPPh3)2-OMe]OTf (6). The cytotoxic activity in vitro of these complexes has been evaluated against three different tumor human cell lines, A549 (lung carcinoma), Jurkat (T-cell leukaemia) and MiaPaca2 (pancreatic carcinoma). All the complexes displayed excellent cytotoxic activity with IC50 values in the low μM range and even in the nM range in some cases. Structure-Activity Relationships (SAR) observed from this family of complexes opens the possibility of designing more potent and selective promising gold(i) anticancer agents.

  8. Intensification Behavior of Mercury Ions on Gold Cyanide Leaching

    Directory of Open Access Journals (Sweden)

    Qiang Zhong

    2018-01-01

    Full Text Available Cyanidation is the main method used to extract gold from gold raw materials; however, a serious problem with this method is the low leaching rate. In order to improve gold leaching, the intensification behavior of mercury ions on gold cyanide leaching, for two types of materials, sulphide gold concentrate and oxide gold ore, was investigated. The results showed that mercury ions, with only a 10−5 M dosage, could significantly intensify leaching and gold recovery. The dissolution behavior of gold plate was also intensified by 10−5 M mercury ions. Microstructure analysis showed that mercury ions intensified the cyanidation corrosion of the gold surface, resulting in a loose structure, where a large number of deep ravines and raised particles were evident across the whole gold surface. The loose structure added contact surface between the gold and cyanide, and accelerated gold dissolution. Moreover, mercury ions obstructed the formation of insoluble products, such as AuCN, Au(OHCN, and Au(OHx, that lead to a passivation membrane on the gold surface, reducing contact between the gold and cyanide. These effects, brought about by mercury ions, change the structure and product of the gold surface during gold cyanidation and promote gold leaching.

  9. Gold and silver/Si nanocomposite layers

    Energy Technology Data Exchange (ETDEWEB)

    Kleps, Irina [National Institute for Research and Development in Microtechnologies (IMT-Bucharest), P.O. Box 38-160, Bucharest (Romania)], E-mail: irinak@imt.ro; Danila, Mihai; Angelescu, Anca; Miu, Mihaela; Simion, Monica; Ignat, Teodora; Bragaru, Adina [National Institute for Research and Development in Microtechnologies (IMT-Bucharest), P.O. Box 38-160, Bucharest (Romania); Dumitru, Lucia; Teodosiu, Gabriela [Institute of Biology, 296 Splaiul Independentei, P.O. Box 56-53, Bucharest, 060031 (Romania)], E-mail: biologie@ibiol.ro

    2007-09-15

    Ag and Au nanolayers were realised by physical and chemical deposition methods on porous silicon (PS) nanostructured surfaces for biomedical applications: support for living cells, biodegradable material for the slow release of drugs/minerals, and as a bioactive material for scaffolds. Au nanoparticles on nanocrystalline Si are widely used in increasing substrate biocompatibility properties. It has an electrochemical potential of + 0.332 mV and surface energy around 25 erg/cm{sup 2}, close to those of living tissues. The Au nanocrystallites orientation on nanocrystalline Si substrates is also of great interest for application in biochemistry; the Au (111)/nc-Si surface has a higher density of atoms compared with Au (100); this favours the attachment of a higher number of atoms and bio-molecules on the gold surface. Ag nanoparticles on nanocrystalline Si are important for the latter's anti-microbial properties. In minute concentrations, Ag is highly toxic to germs while relatively non-toxic to human cells. Microbes are unlikely to develop a resistance against silver, as they do against conventional and highly targeted antibiotics. The Au and Ag nanoparticles/silicon nanocomposite layers as-deposited and thermally treated were investigated by optical microscopy, X-ray diffraction, and biological tests using eukaryotic and prokaryotic cell cultures. The experimental results sustain the use of Au/Si and Ag/Si or combined Ag/Au/Si nanocomposite structures as biocompatible and anti-microbial matrix.

  10. Coal-gold agglomeration: an alternative separation process in gold recovery

    Energy Technology Data Exchange (ETDEWEB)

    Akcil, A.; Wu, X.Q.; Aksay, E.K. [Suleyman Demirel University, Isparta (Turkey). Dept. of Mining Engineering

    2009-07-01

    Considering the increasing environmental concerns and the potential for small gold deposits to be exploited in the future, the uses of environmentally friendly processes are essential. Recent developments point to the potential for greatly increased plant performance through a separation process that combines the cyanide and flotation processes. In addition, this kind of alternative treatment processes to the traditional gold recovery processes may reduce the environmental risks of present small-scale gold mining. Gold recovery processes that applied to different types of gold bearing ore deposits show that the type of deposits plays an important role for the selection of mineral processing technologies in the production of gold and other precious metals. In the last 25 years, different alternative processes have been investigated on gold deposits located in areas where environmental issues are a great concern. In 1988, gold particles were first recovered by successful pilot trial of coal-gold agglomeration (CGA) process in Australia. The current paper reviews the importance of CGA in the production of gold ore and identifies areas for further development work.

  11. Gold Leaching Characteristics and Intensification of a High S and As-Bearing Gold Concentrate

    Science.gov (United States)

    Yang, Yong-bin; Liu, Xiao-liang; Jiang, Tao; Li, Qian; Xu, Bin; Zhang, Yan

    Some high sulfur and arsenic-bearing gold concentrate has a gold leaching rate less than 80% by oxidation roasting-pickling-cyanidation process. The characteristics and intensification of gold leaching were studied systemically. By combining chemical composition and phase analysis, the low gold leaching rate was found to lie in the capsulation of gold by iron-containing phases including iron oxides, arsenopyrite and pyrite. 96.66% of gold in the industrial leaching residue was capsulated and 95.88% of the capsulated turned out to be in the iron-containing phases. The results of laboratory pickling-cyanidation experiments on the calcine and industrial leaching residue presented further demonstration for the fact that gold capsulated in the iron-containing phases was hard to be leached. However, the gold cyanide leaching rate of calcine could be raised over 95% by a reduction roasting-pickling pretreatment which played such a significant role in exposing the capsulated gold that gold leaching was intensified remarkably.

  12. Gold Bead Implantation in Acupoints for Coxofemoral Arthrosis in Dogs: Method Description and Adverse Effects

    Directory of Open Access Journals (Sweden)

    Lars Moe

    2012-09-01

    Full Text Available Gold bead implantation has been used for years as an alternative method to improve function in chronic joint disease both in humans and dogs. The aims of the present study were to describe the technique of implanting 24-karat gold beads around the hip joints of dogs with chronic hip dysplasia, and to record any side effects or complications of such treatment. A prospective placebo-controlled double-blinded clinical trial was performed. Eighty dogs were randomly allocated to treatment or placebo, with 38 in the gold implantation group and 42 in the placebo group, and followed intensely for six months. The implantation technique was simple to perform, using fluoroscopy and with the dogs under inhalation anesthesia for about 30 minutes. Adverse effects, measured as pain or discomfort, were seen for a period of up to four weeks in 15 of the dogs in the gold implantation group, compared to six dogs in the placebo group. During implantation, a technical difficulty occurred as 82% of the dogs showed leakage of blood and/or synovia from the needles. The dogs in the gold implantation group were radiographed 18 months later. Of the 30 dogs that were radiographed at both inclusion and 24 months, 80% (24 dogs showed a deterioration of the coxofemoral arthrosis, the other six had stable disease evaluated by radiography. Migration of gold beads was only observed in one dog.

  13. Attenuated effects of chitosan-capped gold nanoparticles on LPS-induced toxicity in laboratory rats

    International Nuclear Information System (INIS)

    Stefan, Marius; Melnig, Viorel; Pricop, Daniela; Neagu, Anca; Mihasan, Marius; Tartau, Liliana; Hritcu, Lucian

    2013-01-01

    The impact of nanoparticles in medicine and biology has increased rapidly in recent years. Gold nanoparticles (AuNP) have advantageous properties such as chemical stability, high electron density and affinity to biomolecules. However, the effects of AuNP on human body after repeated administration are still unclear. Therefore, the purpose of the present study was to evaluate the effects of gold-11.68 nm (AuNP1, 9.8 μg) and gold-22.22 nm (AuNP2, 19.7 μg) nanoparticles capped with chitosan on brain and liver tissue reactivity in male Wistar rats exposed to lipopolysaccharide (LPS from Escherichia coli serotype 0111:B4, 250 μg) upon 8 daily sessions of intraperitoneal administration. Our results suggest that the smaller size of chitosan-capped AuNP shows the protective effects against LPS-induced toxicity, suggesting a very high potential for biomedical applications. - Highlights: ► Smaller size of chitosan-capped gold nanoparticles acts against LPS-induced toxicity. ► Larger size of chitosan-capped gold nanoparticles agglomerated inside neurons and induced toxicity in combination with LPS. ► Chitosan has excellent biocompatible proprieties. ► Smaller size of chitosan-capped gold nanoparticles demonstrates great potential in biomedical applications.

  14. Green Nanotechnology from Tea: Phytochemicals in Tea as Building Blocks for Production of Biocompatible Gold Nanoparticles.

    Science.gov (United States)

    Nune, Satish K; Chanda, Nripen; Shukla, Ravi; Katti, Kavita; Kulkarni, Rajesh R; Thilakavathi, Subramanian; Mekapothula, Swapna; Kannan, Raghuraman; Katti, Kattesh V

    2009-06-01

    Phytochemicals occluded in tea have been extensively used as dietary supplements and as natural pharmaceuticals in the treatment of various diseases including human cancer. Results on the reduction capabilities of phytochemicals present in tea to reduce gold salts to the corresponding gold nanoparticles are presented in this paper. The phytochemicals present in tea serve the dual roles as effective reducing agents to reduce gold and also as stabilizers to provide robust coating on the gold nanoparticles in a single step. The Tea-generated gold nanoparticles (T-AuNPs), have demonstrated remarkable in vitro stability in various buffers including saline, histidine, HSA, and cysteine solutions. T-AuNPs with phytochemical coatings have shown significant affinity toward prostate (PC-3) and breast (MCF-7) cancer cells. Results on the cellular internalization of T-AuNPs through endocytosis into the PC-3 and MCF-7 cells are presented. The generation of T-AuNPs follows all principles of green chemistry and have been found to be non toxic as assessed through MTT assays. No 'man made' chemicals, other than gold salts, are used in this true biogenic green nanotechnological process thus paving excellent opportunities for their applications in molecular imaging and therapy.

  15. Assessment of gold exposure and contamination in galvanizing workplace by neutron activation analysis

    International Nuclear Information System (INIS)

    Menezes, M.A.B.C.; Amaral, A.M.; Maia, E.C.P.; Albinati, C.C.B.

    2007-01-01

    Gold is not included in the current list of elements considered essential to humans and there are many controversies related to its toxicity. According to the chemical characteristics of the element, Au 1+ is favored for binding at sites with S donor, such as sulfhydryl group (-SH) in proteins in biological systems. This tendency raises the possibility of health-related risk, mainly linked to a long-term exposure to high and low levels of gold. This paper highlights the determination of gold by instrumental neutron activation analysis (INAA) during the assessment of exposure levels to metals and possible workers' contamination in three galvanizing factories applying the same processes. This assessment is aimed at giving support to Worker's Health Awareness Program of the Municipal Department of Health of Belo Horizonte, Minas Gerais, Brazil. INAA, mix of k 0 and monostandard methods was applied to air filter, hair and toenail samples, and to urine samples. Solvent extraction of gold was carried out followed by comparative INAA. The results revealed that gold was present in all matrixes, indicating the exposure in the workplace and suggesting endogenous contamination. Is gold playing a role as a toxic element? (author)

  16. The giant Jiaodong gold province: The key to a unified model for orogenic gold deposits?

    Directory of Open Access Journals (Sweden)

    David I. Groves

    2016-05-01

    Full Text Available Although the term orogenic gold deposit has been widely accepted for all gold-only lode-gold deposits, with the exception of Carlin-type deposits and rare intrusion-related gold systems, there has been continuing debate on their genesis. Early syngenetic models and hydrothermal models dominated by meteoric fluids are now clearly unacceptable. Magmatic-hydrothermal models fail to explain the genesis of orogenic gold deposits because of the lack of consistent spatially – associated granitic intrusions and inconsistent temporal relationships. The most plausible, and widely accepted, models involve metamorphic fluids, but the source of these fluids is hotly debated. Sources within deeper segments of the supracrustal successions hosting the deposits, the underlying continental crust, and subducted oceanic lithosphere and its overlying sediment wedge all have their proponents. The orogenic gold deposits of the giant Jiaodong gold province of China, in the delaminated North China Craton, contain ca. 120 Ma gold deposits in Precambrian crust that was metamorphosed over 2000 million years prior to gold mineralization. The only realistic source of fluid and gold is a subducted oceanic slab with its overlying sulfide-rich sedimentary package, or the associated mantle wedge. This could be viewed as an exception to a general metamorphic model where orogenic gold has been derived during greenschist- to amphibolite-facies metamorphism of supracrustal rocks: basaltic rocks in the Precambrian and sedimentary rocks in the Phanerozoic. Alternatively, if a holistic view is taken, Jiaodong can be considered the key orogenic gold province for a unified model in which gold is derived from late-orogenic metamorphic devolatilization of stalled subduction slabs and oceanic sediments throughout Earth history. The latter model satisfies all geological, geochronological, isotopic and geochemical constraints but the precise mechanisms of auriferous fluid release, like many

  17. Gold nanoparticles produced in a microalga

    International Nuclear Information System (INIS)

    Luangpipat, Tiyaporn; Beattie, Isabel R.; Chisti, Yusuf; Haverkamp, Richard G.

    2011-01-01

    An efficient biological route to production of gold nanoparticles which allows the nanoparticles to be easily recovered remains elusive. Live cells of the green microalga Chlorella vulgaris were incubated with a solution of gold chloride and harvested by centrifugation. Nanoparticles inside intact cells were identified by transmission electron microscopy and confirmed to be metallic gold by synchrotron based X-ray powder diffraction and X-ray absorption spectroscopy. These intracellular gold nanoparticles were 40–60 nm in diameter. At a concentration of 1.4% Au in the alga, a better than 97% recovery of the gold from solution was achieved. A maximum of 4.2% Au in the alga was obtained. Exposure of C. vulgaris to solutions containing dissolved salts of palladium, ruthenium, and rhodium also resulted in the production of the corresponding nanoparticles within the cells. These were surmised to be also metallic, but were produced at a much lower intracellular concentration than achieved with gold. Iridium was apparently toxic to the alga. No nanoparticles were observed using platinum solutions. C. vulgaris provides a possible route to large scale production of gold nanoparticles.

  18. Gel Electrophoresis of Gold-DNA Nanoconjugates

    Directory of Open Access Journals (Sweden)

    T. Pellegrino

    2007-01-01

    Full Text Available Gold-DNA conjugates were investigated in detail by a comprehensive gel electrophoresis study based on 1200 gels. A controlled number of single-stranded DNA of different length was attached specifically via thiol-Au bonds to phosphine-stabilized colloidal gold nanoparticles. Alternatively, the surface of the gold particles was saturated with single stranded DNA of different length either specifically via thiol-Au bonds or by nonspecific adsorption. From the experimentally determined electrophoretic mobilities, estimates for the effective diameters of the gold-DNA conjugates were derived by applying two different data treatment approaches. The first method is based on making a calibration curve for the relation between effective diameters and mobilities with gold nanoparticles of known diameter. The second method is based on Ferguson analysis which uses gold nanoparticles of known diameter as reference database. Our study shows that effective diameters derived from gel electrophoresis measurements are affected with a high error bar as the determined values strongly depend on the method of evaluation, though relative changes in size upon binding of molecules can be detected with high precision. Furthermore, in this study, the specific attachment of DNA via gold-thiol bonds to Au nanoparticles is compared to nonspecific adsorption of DNA. Also, the maximum number of DNA molecules that can be bound per particle was determined.

  19. Nature vs. nurture: gold perpetuates "stemness".

    Science.gov (United States)

    Paul, Willi; Sharma, Chandra P; Deb, Kaushik Dilip

    2011-01-01

    Adult tissues contain quiescent reservoirs of multipotent somatic stem cells and pluripotent embryonic-like stem cells (ELSCs). Credited with regenerative properties gold is used across both -contemporary and -ancient medicines. Here, we show that gold exerted these effects by enhancing the pool of pluripotent ELSC while improving their stemness. We used hESCs as an in-vitro model to understand if gold could enhance self-renewal and pluripotency. Swarna-bhasma (SB), an ancient Indian gold microparticulate (41.1 nm), preparation, reduced spontaneous-differentiation, improved self-renewal, pluripotency and proliferation of hESCs. Colloidal gold-nanoparticles (GNP) (15.59 nm) were tested to confirm that the observations were attributable to nanoparticulate-gold. SB and GNP exposure: maintained -stemness, -karyotypic stability, enhanced pluripotency till day-12, increased average colony-sizes, and reduced the number of autonomously-derived differentiated FGFR1 positive fibroblast-niche-cells/colony. Particulate-gold induced upregulation of FGFR1 and IGF2 expression, and decrease in IGF1 secretion indicates IGF1/2 mediated support for enhanced pluripotency and self-renewal in hESCs.

  20. Urban artisanal gold shops and mercury emissions

    International Nuclear Information System (INIS)

    Cordy, P.; Veiga, M.; Carrasco, V.H.G.

    2008-01-01

    Artisanal miners in developing countries use mercury amalgamation processes to extract gold. The amalgams are then refined before being sold on to urban gold shops. The amalgams can often contain between 2 to 40 per cent mercury. Unburned amalgams are also often sold directly to gold shops. There are serious health risks for shop employees and nearby populations when the gold is melted and further purified. Studies have shown that mercury concentrations in the ambient air of gold shops often exceeds World Health Organization (WHO) limits by an order of magnitude or more. This study examined the practices and technologies used to refine gold in Latin America and Indonesia. The study compared and contrasted various refining methods and their resulting mercury emissions. Methods of reducing mercury emissions were also investigated, including a filtration system designed to capture 80 per cent of mercury emissions. Barriers to implementing mercury emissions reduction plans were also investigated. It was concluded that the design of urban gold shops must include condensers, fume hoods, and efficient mercury capture systems. 15 refs