WorldWideScience

Sample records for resemble virtual gold

  1. Artifacts resembling budding bacteria produced in placer-gold amalgams by nitric acid leaching

    Science.gov (United States)

    Watterson, J.R.

    1994-01-01

    Microscopic filiform morphologies in gold which are indistinguishable from forms originally interpreted as bacterial in origin were produced in the laboratory by treating amalgams made from natural and artificial gold with hot nitric acid. Textures ranging from cobblestone to deeply crenulated to nodular filiform were produced in the laboratory from all tested natural and artificial gold amalgams; analogous textures widespread in Alaskan placer gold may have a similar inorganic origin. These results indicate that morphology alone cannot be considered adequate evidence of microbial involvement in gold formation. -Author

  2. PyGOLD: a python based API for docking based virtual screening workflow generation.

    Science.gov (United States)

    Patel, Hitesh; Brinkjost, Tobias; Koch, Oliver

    2017-08-15

    Molecular docking is one of the successful approaches in structure based discovery and development of bioactive molecules in chemical biology and medicinal chemistry. Due to the huge amount of computational time that is still required, docking is often the last step in a virtual screening approach. Such screenings are set as workflows spanned over many steps, each aiming at different filtering task. These workflows can be automatized in large parts using python based toolkits except for docking using the docking software GOLD. However, within an automated virtual screening workflow it is not feasible to use the GUI in between every step to change the GOLD configuration file. Thus, a python module called PyGOLD was developed, to parse, edit and write the GOLD configuration file and to automate docking based virtual screening workflows. The latest version of PyGOLD, its documentation and example scripts are available at: http://www.ccb.tu-dortmund.de/koch or http://www.agkoch.de. PyGOLD is implemented in Python and can be imported as a standard python module without any further dependencies. oliver.koch@agkoch.de, oliver.koch@tu-dortmund.de. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  3. Hedging Capabilities of Bitcoin. Is it the virtual gold?

    OpenAIRE

    Dyhrberg, Anne Haubo

    2015-01-01

    This paper sets out to explore the hedging capabilities of bitcoin by applying the asymmetric GARCH methodology used in investigation of gold. The results show that bitcoin can clearly be used as a hedge against stocks in the Financial Times Stock Exchange Index. Additionally bitcoin can be used as a hedge against the American dollar in the short-term. Bitcoin thereby possess some of the same hedging abilities as gold and can be included in the variety of tools available to market analysts to...

  4. Does facial resemblance enhance cooperation?

    Directory of Open Access Journals (Sweden)

    Trang Giang

    Full Text Available Facial self-resemblance has been proposed to serve as a kinship cue that facilitates cooperation between kin. In the present study, facial resemblance was manipulated by morphing stimulus faces with the participants' own faces or control faces (resulting in self-resemblant or other-resemblant composite faces. A norming study showed that the perceived degree of kinship was higher for the participants and the self-resemblant composite faces than for actual first-degree relatives. Effects of facial self-resemblance on trust and cooperation were tested in a paradigm that has proven to be sensitive to facial trustworthiness, facial likability, and facial expression. First, participants played a cooperation game in which the composite faces were shown. Then, likability ratings were assessed. In a source memory test, participants were required to identify old and new faces, and were asked to remember whether the faces belonged to cooperators or cheaters in the cooperation game. Old-new recognition was enhanced for self-resemblant faces in comparison to other-resemblant faces. However, facial self-resemblance had no effects on the degree of cooperation in the cooperation game, on the emotional evaluation of the faces as reflected in the likability judgments, and on the expectation that a face belonged to a cooperator rather than to a cheater. Therefore, the present results are clearly inconsistent with the assumption of an evolved kin recognition module built into the human face recognition system.

  5. Resemblances in the Wedding and Natal Customs

    OpenAIRE

    Reneta Zlateva; Zlatozhivka Zdravkova

    2011-01-01

    The present article describes the natal rites and customs of the Azerbaijan and Bulgarian nations. Special attention is paid to the resemblances in the practicing and understanding of the traditions. Despite the fact that the two nations live in regions remote from each other, they have common beliefs and strive to provide prosperity for the home, family and children.

  6. Social perception of facial resemblance in humans.

    Science.gov (United States)

    DeBruine, Lisa M; Jones, Benedict C; Little, Anthony C; Perrett, David I

    2008-02-01

    Two lines of reasoning predict that highly social species will have mechanisms to influence behavior toward individuals depending on their degree of relatedness. First, inclusive fitness theory leads to the prediction that organisms will preferentially help closely related kin over more distantly related individuals. Second, evaluation of the relative costs and potential benefits of inbreeding suggests that the degree of kinship should also be considered when choosing a mate. In order to behaviorally discriminate between individuals with different levels of relatedness, organisms must be able to discriminate cues of kinship. Facial resemblance is one such potential cue in humans. Computer-graphic manipulation of face images has made it possible to experimentally test hypotheses about human kin recognition by facial phenotype matching. We review recent experimental evidence that humans respond to facial resemblance in ways consistent with inclusive fitness theory and considerations of the costs of inbreeding, namely by increasing prosocial behavior and positive attributions toward self-resembling images and selectively tempering attributions of attractiveness to other-sex faces in the context of a sexual relationship.

  7. Multiple ureterolithiasis resembling steinstrasse: An unusual presentation

    Directory of Open Access Journals (Sweden)

    Praveen Kumar Pandey

    2014-12-01

    Full Text Available Steinstrasse or “stone street” is an expected complication after extracorporeal shock wave lithotripsy in patients with high stone burden. However, there are published reports of multiple ureterolithiasis resembling steinstrasse in patients with distal renal tubular acidosis. Here we report an uncommon case of a 60-year-old woman who presented with right renal calculi. Her right ureter was studded with multiple calculi up to the vesicoureteric junction. The affected right kidney was nonfunctional and was managed by nephroureterectomy.

  8. Body elimination attitude family resemblance in Kuwait.

    Science.gov (United States)

    Al-Fayez, Ghenaim; Awadalla, Abdelwahid; Arikawa, Hiroko; Templer, Donald I; Hutton, Shane

    2009-12-01

    The purpose of the present study was to determine the family resemblance of attitude toward body elimination in Kuwaiti participants. This study was conceptualized in the context of the theories of moral development, importance of cleanliness in the Muslim religion, cross-cultural differences in personal hygiene practices, previous research reporting an association between family attitudes and body elimination attitude, and health implications. The 24-item Likert-type format Body Elimination Attitude Scale-Revised was administered to 277 Kuwaiti high school students and 437 of their parents. Females scored higher, indicating greater disgust, than the males. Moreover, sons' body elimination attitude correlated more strongly with fathers' attitude (r = .85) than with that of the mothers (r = .64). Daughters' attitude was similarly associated with the fathers' (r = .89) and the mothers' attitude (r = .86). The high correlations were discussed within the context of Kuwait having a collectivistic culture with authoritarian parenting style. The higher adolescent correlations, and in particular the boys' correlation with fathers than with mothers, was explained in terms of the more dominant role of the Muslim father in the family. Public health and future research implications were suggested. A theoretical formulation was advanced in which "ideal" body elimination attitude is relative rather than absolute, and is a function of one's life circumstances, one's occupation, one's culture and subculture, and the society that one lives in.

  9. 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.

  10. Saving Money and Time with Virtual Server

    CERN Document Server

    Sanders, Chris

    2006-01-01

    Microsoft Virtual Server 2005 consistently proves to be worth its weight in gold, with new implementations thought up every day. With this product now a free download from Microsoft, scores of new users are able to experience what the power of virtualization can do for their networks. This guide is aimed at network administrators who are interested in ways that Virtual Server 2005 can be implemented in their organizations in order to save money and increase network productivity. It contains information on setting up a virtual network, virtual consolidation, virtual security, virtual honeypo

  11. Realistic Visualization of Virtual Views and Virtual Cinema

    DEFF Research Database (Denmark)

    Livatino, Salvatore

    2005-01-01

    Realistic Virtual View Visualization is a new field of research which has received increasing attention in recent years. It is strictly related to the increased popularity of virtual reality and the spread of its applications, among which virtual photography and cinematography. The use of computer...... generated characters, "virtual actors", in the motion picture production increases every day. While the most known computer graphics techniques have largely been adopted successfully in nowadays fictions, it still remains very challenging to implement virtual actors which would resemble, visually, human...... is then gaining consensus: the augmented actor. Fundamental concepts and examples of methods proposed for realistic view synthesis, based on the transfer of photorealism from reference photographs to novel views, will be presented. The application of methods for realistic image synthesis to virtual cinematography...

  12. Parental Investment and Resemblance: Replications, Refinements, and Revisions

    Directory of Open Access Journals (Sweden)

    Anthony A. Volk

    2007-01-01

    Full Text Available Evolutionary theory predicts that men should be more concerned with issues of false paternity than women should be concerned with false maternity. In an earlier study (Volk and Quinsey, 2002, we studied how infant cues of resemblance influenced adults' hypothetical adoption decisions. We found that self-perceived cues of resemblance were significantly more important in men's decisions than in women's. Since that study was published, conflicting results have been reported regarding a sex-difference in the importance of cues of resemblance for adoption preference. We therefore sought to replicate our findings in three new studies. In all three studies, we replicated the initial finding of a larger correlation between ratings of resemblance and ratings of adoption preference among men than among women. We also found a trend towards slightly higher global resemblance scores in younger children, suggesting that adults view infants as more anonymous and/or less uniquely distinctive than older children. However, there was wide variance in both the global resemblance and developmental changes in resemblance amongst the different child stimuli used.

  13. Virtually teaching virtual leadership

    DEFF Research Database (Denmark)

    Henriksen, Thomas Duus; Nielsen, Rikke Kristine; Børgesen, Kenneth

    2017-01-01

    This paper seeks to investigate the challenges to virtual collaboration and leadership on basis of findings from a virtual course on collaboration and leadership. The course used for this experiment was designed as a practical approach, which allowed participants to experience curriculum phenomena....... This experimental course provided insights into the challenges involved in virtual processes, and those experiences where used for addressing the challenges that virtual leadership is confronted with. Emphasis was placed on the reduction of undesired virtual distance and its consequences through affinity building....... We found that student scepticism appeared when a breakdown resulted in increasing virtual distance, and raises questions on how leaders might translate or upgrade their understandings of leadership to handling such increased distance through affinity building....

  14. 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...

  15. Organizaciones Virtuales Organizaciones Virtuales

    Directory of Open Access Journals (Sweden)

    Gladis Cecilia Villegas Arias

    2003-06-01

    Full Text Available Virtual Organizations are new organizational forms originated from both the replacementof face to face communications by remote communications supported by electronic means,and from the accesibility of real time information about the operation of the company, forall employees.This article pursues the following goals: 1 To define virtual organization, review its sociotechnical antecedents and propose a preliminary classification into inter-organizationaland intra-organizational forms.  2 To discuss the characteristics of virtual organizationsand their impact on organizational design, and 3 To compare virtual organizations toother organizational forms.Las organizaciones virtuales son formas organizativas nuevas, que resultan de: primero, reemplazar las interacciones cara a cara con interacciones remotas, soportadas por comunicaciones electrónicas y segundo,  proveer acceso en tiempo real a toda la información de la empresa para todos los trabajadores.En este artículo se busca: 1 Definir organización virtual, revisar sus antecedentes y proponeruna clasificación básica preliminar de las mismas  2 Discutir las características de las organizaciones virtuales y sus implicaciones para el diseño organizativo 3 Comparar estaforma organizativa a las formas organizativas no virtuales.

  16. Virtual cystoscopy.

    Science.gov (United States)

    Mohammed, Aza; Simpson, Adam; Zamora, Ignacio; Gilliland, Leslie

    2008-07-01

    Bladder cancer is a common problem facing urologists worldwide. The gold standard for its diagnosis and follow-up is the direct visualization of the tumor using conventional cystoscopy. Despite having high sensitivity and specificity for detecting bladder cancer, conventional cystoscopy is regarded as an invasive procedure which is associated with several complications. In addition, regular follow-up of patients with bladder cancer is a financial burden on the health system. With the progressive development in diagnostic imaging and medical computer software technologies, it was possible to generate virtual reality images to aid the clinician to inspect the interior of the bladder in real time. This technology is considered as a safe test for bladder cancer diagnosis and follow-up, and it is associated with cancer detection rates comparable with conventional cystoscopy. However, it is associated with some drawbacks that limit its use in routine clinical practice at the current time. In this paper, we review the development and clinical applications of this technology.

  17. 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...

  18. 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

  19. Spousal resemblance in psychopathology: A comparison of parents of children with and without psychopathology

    NARCIS (Netherlands)

    Wesseldijk, L. W.; Dieleman, G. C.; Lindauer, R. J. L.; Bartels, M.; Willemsen, G.; Hudziak, J. J.; Boomsma, D. I.; Middeldorp, C. M.

    2016-01-01

    Spouses resemble each other for psychopathology, but data regarding spousal resemblance in externalizing psychopathology, and data regarding spousal resemblance across different syndromes (e.g. anxiety in wives and attention deficit/hyperactivity disorder [ADHD] in husbands) are limited. Moreover,

  20. RESEMBLANCE OF INDIRECTNESS IN POLITENESS OF EFL LEARNERS’ REQUEST REALIZATIONS

    Directory of Open Access Journals (Sweden)

    Indawan Syahri

    2013-07-01

    Full Text Available Abstract: Politeness principles are universally utilized by the speakers of any language when realizing various speech acts. However, the speakers of particular languages relatively apply politeness due to the cultural norms embedded. The present study attempts to delineate how the Indonesian learners of English (ILE apply the politeness principles in request realizations. Specifically it devotes to the types of politeness strategies applied and resemblance of the indirectness in politeness strategies in requesting acts. The FTAs and indirectness are the theoretical bases used to trace the typologies of both politeness and request strategies. The data werere collected by means of certain elicitation techniques, i.e. DCTs and Role-plays. The analyses werere done through three stages; determining request strategies, politeness strategies, and resemblance of indirectness in politeness. The results show that the indirectness generally is parallel to politeness. Besides, some pragmatic transfers are found in terms of applying native-culture norms in realizing target speech acts.

  1. Allergic Contact Dermatitis to Benzoyl Peroxide Resembling Impetigo.

    Science.gov (United States)

    Kim, Changhyun; Craiglow, Brittany G; Watsky, Kalman L; Antaya, Richard J

    2015-01-01

    A 17-year-old boy presented with recurring severe dermatitis of the face of 5-months duration that resembled impetigo. He had been treated with several courses of antibiotics without improvement. Biopsy showed changes consistent with allergic contact dermatitis and patch testing later revealed sensitization to benzoyl peroxide, which the patient had been using for the treatment of acne vulgaris. © 2015 Wiley Periodicals, Inc.

  2. Native valve endocarditis caused by an organism resembling Corynebacterium striatum.

    OpenAIRE

    Markowitz, S M; Coudron, P E

    1990-01-01

    An organism resembling Corynebacterium striatum was isolated from the blood of a patient with acute aortic valvular insufficiency and no history of valvular heart disease. At autopsy, histopathologic examination of the aortic valve revealed pleomorphic gram-positive bacilli and destruction of valvular tissue. Our isolate differed from other nondiphtherial corynebacteria, including the type strain of C. striatum (ATCC 6940), in its ability to reduce nitrite. Nitrite reduction may be useful for...

  3. Detecting analogical resemblance without retrieving the source analogy.

    Science.gov (United States)

    Kostic, Bogdan; Cleary, Anne M; Severin, Kaye; Miller, Samuel W

    2010-06-01

    We examined whether people can detect analogical resemblance to an earlier experimental episode without being able to recall the experimental source of the analogical resemblance. We used four-word analogies (e.g., robin-nest/beaver-dam), in a variation of the recognition-without-cued-recall method (Cleary, 2004). Participants studied word pairs (e.g., robin-nest) and were shown new word pairs at test, half of which analogically related to studied word pairs (e.g., beaver-dam) and half of which did not. For each test pair, participants first attempted to recall an analogically similar pair from the study list. Then, regardless of whether successful recall occurred, participants were prompted to rate the familiarity of the test pair, which was said to indicate the likelihood that a pair that was analogically similar to the test pair had been studied. Across three experiments, participants demonstrated an ability to detect analogical resemblance without recalling the source analogy. Findings are discussed in terms of their potential relevance to the study of analogical reasoning and insight, as well as to the study of familiarity and recognition memory.

  4. Knowledge-driven GIS modeling technique for gold exploration, Bulghah gold mine area, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Ahmed A. Madani

    2011-12-01

    Full Text Available This research aims to generate a favorability map for gold exploration at the Bulghah gold mine area using integration of geo-datasets within a GIS environment. Spatial data analyses and integration of different geo-datasets are carried out based on knowledge-driven and weighting technique. The integration process involves the weighting and scoring of different layers affecting the gold mineralization at the study area using the index overlay method within PCI Geomatica environment. Generation of the binary predictor maps for lithology, lineaments, faults and favorable contacts precede the construction of the favorability map. About 100 m buffer zones are generated for favorable contacts, lineaments and major faults layers. Internal weighting is assigned to each layer based on favorability for gold mineralization. The scores for lithology, major faults, lineaments and favorable contacts layers in the constructed favorability map are 50%, 25%, 10% and 15%, respectively. Final favorability map for the Bulghah gold mine area shows the recording of two new sites for gold mineralization located at the northern and southern extensions of tonalite–diorite intrusions. The northern new site is now exploited for gold from the Bulghah North mine. The southern new site is narrow and small; its rocks resemble those of the Bulghah gold mine.

  5. Virtual Box

    DEFF Research Database (Denmark)

    Davis, Hilary; Skov, Mikael B.; Stougaard, Malthe

    2007-01-01

    . This paper reports on the design, implementation and initial evaluation of Virtual Box. Virtual Box attempts to create a physical and engaging context in order to support reciprocal interactions with expressive content. An implemented version of Virtual Box is evaluated in a location-aware environment...

  6. Resemblance operations and conceptual complexity in animal metaphors

    Directory of Open Access Journals (Sweden)

    Aneider Iza Ervitia

    2012-07-01

    Full Text Available For over thirty years cognitive linguists have devoted much effort to the study of metaphors based on the correlation of events in human experience to the detriment of the more traditional notion of resemblance metaphor, which exploits perceived similarities among objects. Grady (1999 draws attention to this problem and calls for a more serious study of the latter type of metaphor. The present paper takes up this challenge on the basis of a small corpus of ‘animal’ metaphors in English, which are essentially based on resemblance. Contrary to previous analyses by cognitive linguists (e.g. Lakoff & Turner 1989, Ruiz de Mendoza Ibáñez, 1998, who claim that such metaphors are based on a single mapping generally involving comparable behavioral attributes, I will argue that we have a more complex situation which involves different patterns of conceptual interaction. In this respect, I have identified cases of (i animal metaphors interacting with high-level (i.e. grammatical metaphors and metonymies, of (ii (situational animal metaphors whose source domains are constructed metonymically (cf. Goossens 1990; Ruiz de Mendoza Ibáñez & Díez Velasco 2002, and of (iii animal metaphors interacting with other metaphors thereby giving rise to metaphoric amalgams (cf. Ruiz de Mendoza Ibáñez & Galera Masegosa 2011.

  7. Wireless virtualization

    CERN Document Server

    Wen, Heming; Le-Ngoc, Tho

    2013-01-01

    This SpringerBriefs is an overview of the emerging field of wireless access and mobile network virtualization. It provides a clear and relevant picture of the current virtualization trends in wireless technologies by summarizing and comparing different architectures, techniques and technologies applicable to a future virtualized wireless network infrastructure. The readers are exposed to a short walkthrough of the future Internet initiative and network virtualization technologies in order to understand the potential role of wireless virtualization in the broader context of next-generation ubiq

  8. Virtual marketing in virtual enterprises

    OpenAIRE

    Ale Ebrahim, Nader; Fattahi, Hamaid Ali; Golnam, Arash

    2008-01-01

    Virtualization caused tremendous evolution in the economics of marketing channels, patterns of physical distribution and the structure of distributors and developed a new concept that is known as virtual marketing (VM). VM combines the powerful technologies of interactive marketing and virtual reality. Virtual enterprise (VE) refers to an organization not having a clear physical locus. In other words, VE is an organization distributed geographically and whose work is coordinated through e...

  9. The Virtual Grand Tour as Educational Paradigm

    DEFF Research Database (Denmark)

    Hansen, Per Skafte; Mouritsen, Lars

    2001-01-01

    The Virtual Grand Tour as defined here bears some resemblance to its 18th century ancestor: a wide range of individual topics are treated as a whole; a tutor, whether real or simulated, present or remote, is provided; a set of problem solving tools forms an integrated part of the "traveller...

  10. 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.

  11. A case of cervical radiation radiculopathy resembling motor neuron disease

    International Nuclear Information System (INIS)

    Mitsunaga, Yoshihiro; Yoshimura, Takeo; Hara, Hideo; Yamada, Takeshi; Kira, Jun-ichi; Kobayashi, Takuro

    1998-01-01

    A 67-year-old man developed slowly progressive muscular weakness in the bilateral upper extremities (C5-7 regions) without signs of sensory deficit following the cervical radiation therapy (70.5 Gy) for right laryngeal cancer 4 years before. These clinical signs resembled those of lower motor neuron disease. MRI with gadolinium-DTPA, however, showed enhancement in the bilateral C5 and C6 anterior roots, suggesting the cervical radiculopathy due to radiotherapy. It is known that radiation to the spinal cord can lead to ''selective anterior horn cell injury''. This is the first case report of the cervical radiation radiculopathy, which, if without MRI, might be classified into selective anterior horn cell injury. Suggestion is made for the hypothesis that the spinal motoneuron loss in radiation myelopathy would be caused by retrograde degeneration due to anterior root damages. (author)

  12. A case of cervical radiation radiculopathy resembling motor neuron disease

    Energy Technology Data Exchange (ETDEWEB)

    Mitsunaga, Yoshihiro; Yoshimura, Takeo; Hara, Hideo; Yamada, Takeshi; Kira, Jun-ichi; Kobayashi, Takuro [Kyushu Univ., Fukuoka (Japan). Faculty of Medicine

    1998-05-01

    A 67-year-old man developed slowly progressive muscular weakness in the bilateral upper extremities (C5-7 regions) without signs of sensory deficit following the cervical radiation therapy (70.5 Gy) for right laryngeal cancer 4 years before. These clinical signs resembled those of lower motor neuron disease. MRI with gadolinium-DTPA, however, showed enhancement in the bilateral C5 and C6 anterior roots, suggesting the cervical radiculopathy due to radiotherapy. It is known that radiation to the spinal cord can lead to ``selective anterior horn cell injury``. This is the first case report of the cervical radiation radiculopathy, which, if without MRI, might be classified into selective anterior horn cell injury. Suggestion is made for the hypothesis that the spinal motoneuron loss in radiation myelopathy would be caused by retrograde degeneration due to anterior root damages. (author)

  13. RESEMBLANCE OPERATIONS AND CONCEPTUAL COMPLEXY IN ANIMAL METAPHORS

    Directory of Open Access Journals (Sweden)

    Aneider Iza Ervitia

    2012-07-01

    Full Text Available

    For over thirty years cognitive linguists have devoted much effort to the study of metaphors based on the correlation of events in human experience to the detriment of the more traditional notion of resemblance metaphor, which exploits perceived similarities among objects. Grady (1999 draws attention to this problem and calls for a more serious study of the latter type of metaphor. The present paper takes up this challenge on the basis of a small corpus of ‘animal’ metaphors in English, which are essentially based on resemblance. Contrary to previous analyses by cognitive linguists (e.g. Lakoff & Turner 1989, Ruiz de Mendoza Ibáñez, 1998, who claim that such metaphors are based on a single mapping generally involving comparable behavioral attributes, I will argue that we have a more complex situation which involves different patterns of conceptual interaction. In this respect, I have identified cases of (i animal metaphors interacting with high-level (i.e. grammatical metaphors and metonymies, of (ii (situational animal metaphors whose source domains are constructed metonymically (cf. Goossens 1990; Ruiz de Mendoza Ibáñez & Díez Velasco 2002, and of (iii animal metaphors interacting with other metaphors thereby giving rise to metaphoric amalgams (cf. Ruiz de Mendoza Ibáñez & Galera Masegosa 2011.

  14. Evaluation of Security Mechanisms for Virtual Organizations

    Science.gov (United States)

    Wu, Jake; Periorellis, Panos

    GOLD project is concerned with dynamic formation and management of virtual organizations in order to exploit market opportunities. The project aims to deliver the enabling technology to support the full lifecycle of such VOs. A set of middleware technologies have been designed and implemented to address issues such as trust, security, contract management, monitoring and information management for virtual collaboration between companies. In this paper we will showcase some of the more general requirements for authentication and authorization in GOLD VOs. In conjunction with these requirements we evaluate some of the more popular tools that are currently available in dealing with these issues, together with our own approach in addressing these problems.

  15. Controlled synthesis of gold nanoparticles by fluorescent light irradiation

    International Nuclear Information System (INIS)

    Kim, Jun-Hyun; Lavin, Brian W; Burnett, Roarke D; Boote, Brett W

    2011-01-01

    A novel photochemical synthesis of size-controlled gold nanoparticles was reliably accomplished via both a direct reduction and a seeded-growth method at room temperature under the irradiation of fluorescent light. These methods utilized the intensity of fluorescent light that closely resembles daily sunlight (∼100 mW cm -2 ). This effectively allowed for the formation of gold nanoparticles with tunable sizes simply by controlling the concentration of trisodium citrate and gold chloride. The broad band fluorescent light was found to be an efficient source for inducing the formation of gold nanoparticles at ambient conditions. The size distribution and absorption property of the resulting nanoparticles were thoroughly characterized by scanning/transmission electron microscopy, dynamic light scattering, UV-visible spectroscopy and powder x-ray diffraction. This photochemical synthesis demonstrates, for the first time, the reliable preparation of gold nanoparticles at room temperature upon irradiation with fluorescent light.

  16. Virtual volatility

    Science.gov (United States)

    Silva, A. Christian; Prange, Richard E.

    2007-03-01

    We introduce the concept of virtual volatility. This simple but new measure shows how to quantify the uncertainty in the forecast of the drift component of a random walk. The virtual volatility also is a useful tool in understanding the stochastic process for a given portfolio. In particular, and as an example, we were able to identify mean reversion effect in our portfolio. Finally, we briefly discuss the potential practical effect of the virtual volatility on an investor asset allocation strategy.

  17. Virtual bronchoscopy

    International Nuclear Information System (INIS)

    Rogalla, P.; Meiri, N.; Hamm, B.; Rueckert, J.C.; Schmidt, B.; Witt, C.

    2001-01-01

    Flexible bronchoscopy represents a clinically well-established invasive diagnostic tool. Virtual bronchoscopies, calculated from thin-slice CT sections, allow astonishing immitations of reality although principal differences exist between both technologies: the Fact that colour representation is artificial and concommitant interventions are impossible limits the clinical use of virtual bronchoscopy. However, its value increases when calculations can be attained within minutes due to technological advancements, and when virtually any chest CT is suitable for further postprocessing. Indications, findings and the clinical role of virtual bronchoscopy are discussed. (orig.) [de

  18. Virtual projects

    DEFF Research Database (Denmark)

    Svejvig, Per; Commisso, Trine Hald

    2012-01-01

    that the best practice knowledge has not permeated sufficiently to the practice. Furthermore, the appropriate application of information and communication technology (ICT) remains a big challenge, and finally project managers are not sufficiently trained in organizing and conducting virtual projects....... The overall implications for research and practice are to acknowledge virtual project management as very different to traditional project management and to address this difference.......Virtual projects are common with global competition, market development, and not least the financial crisis forcing organizations to reduce their costs drastically. Organizations therefore have to place high importance on ways to carry out virtual projects and consider appropriate practices...

  19. On the resemblance of synapse formation and CNS myelination.

    Science.gov (United States)

    Almeida, R G; Lyons, D A

    2014-09-12

    The myelination of axons in the central nervous system (CNS) is essential for nervous system formation, function and health. CNS myelination continues well into adulthood, but not all axons become myelinated. Unlike the peripheral nervous system, where we know of numerous axon-glial signals required for myelination, we have a poor understanding of the nature or identity of such molecules that regulate which axons are myelinated in the CNS. Recent studies have started to elucidate cell behavior during myelination in vivo and indicate that the choice of which axons are myelinated is made prior to myelin sheath generation. Here we propose that interactions between axons and the exploratory processes of oligodendrocyte precursor cells (OPCs) lead to myelination and may be similar to those between dendrites and axons that prefigure and lead to synapse formation. Indeed axons and OPCs form synapses with striking resemblance to those of neurons, suggesting a similar mode of formation. We discuss families of molecules with specific functions at different stages of synapse formation and address studies that implicate the same factors during axon-OPC synapse formation and myelination. We also address the possibility that the function of such synapses might directly regulate the myelinating behavior of oligodendrocyte processes in vivo. In the future it may be of benefit to consider these similarities when taking a candidate-based approach to dissect mechanisms of CNS myelination. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  20. A Para-Canalicular Abscess Resembling an Inflamed Chalazion

    Directory of Open Access Journals (Sweden)

    Diamantis Almaliotis

    2013-01-01

    Full Text Available Background. Lacrimal infections by Actinomyces are rare and commonly misdiagnosed for long periods of time. They account for 2% of all lacrimal diseases. Case Report. We report a case of a 70-year-old female patient suffering from a para-canalicular abscess in the medial canthus of the left eye, beside the lower punctum lacrimale, resembling a chalazion. Purulence exited from the punctum lacrimale due to inflammation of the inferior canaliculus (canaliculitis. When pressure was applied to the mass, a second exit of purulence was also observed under the palpebral conjunctiva below the lacrimal caruncle. A surgical excision was performed followed by administration of local antibiotic therapy. The histopathological examination of the extracted mass revealed the existence of actinomycosis. Conclusion. Persistent or recurrent infections and lumps of the eyelids should be thoroughly investigated. Actinomyces as a causative agent should be considered. Differential diagnosis is broad and should include canaliculitis, chalazion, and multiple types of neoplasias. For this reason, in nonconclusive cases, a histopathological examination should be performed.

  1. A para-canalicular abscess resembling an inflamed chalazion.

    Science.gov (United States)

    Almaliotis, Diamantis; Nakos, Elias; Siempis, Thomas; Koletsa, Triantafyllia; Kostopoulos, Ioannis; Chatzipantazi, Maria; Karampatakis, Vasileios

    2013-01-01

    Background. Lacrimal infections by Actinomyces are rare and commonly misdiagnosed for long periods of time. They account for 2% of all lacrimal diseases. Case Report. We report a case of a 70-year-old female patient suffering from a para-canalicular abscess in the medial canthus of the left eye, beside the lower punctum lacrimale, resembling a chalazion. Purulence exited from the punctum lacrimale due to inflammation of the inferior canaliculus (canaliculitis). When pressure was applied to the mass, a second exit of purulence was also observed under the palpebral conjunctiva below the lacrimal caruncle. A surgical excision was performed followed by administration of local antibiotic therapy. The histopathological examination of the extracted mass revealed the existence of actinomycosis. Conclusion. Persistent or recurrent infections and lumps of the eyelids should be thoroughly investigated. Actinomyces as a causative agent should be considered. Differential diagnosis is broad and should include canaliculitis, chalazion, and multiple types of neoplasias. For this reason, in nonconclusive cases, a histopathological examination should be performed.

  2. Autosomal dominant syndrome resembling Coffin-Siris syndrome.

    Science.gov (United States)

    Flynn, Maureen A; Milunsky, Jeff M

    2006-06-15

    Coffin-Siris syndrome is a multiple congenital anomaly/mental retardation syndrome with phenotypic variability [OMIM 135900]. The diagnosis is based solely on clinical findings, as there is currently no molecular, biochemical, or cytogenetic analysis available to confirm a diagnosis. Although typically described as an autosomal recessive disorder, autosomal dominant inheritance has also been infrequently reported. We describe a mother and her two daughters who all have features that resemble Coffin-Siris syndrome. However, this is not a completely convincing diagnosis given that hypertelorism is not a feature of Coffin-Siris syndrome and the family is relatively mildly affected. Yet, this family provides further evidence of an autosomal dominant mode of inheritance for a likely variant of Coffin-Siris syndrome (at least in some families). In addition, Sibling 1 had premature thelarche. She is the second reported individual within the spectrum of Coffin-Siris syndrome to have premature thelarche, indicating that it may be a rare clinical feature. Copyright 2006 Wiley-Liss, Inc.

  3. Atypical mycobacterial infection resembles sporotrichosis in elderly patient

    Directory of Open Access Journals (Sweden)

    Siti Nurani Fauziah

    2016-06-01

    Full Text Available Atypical mycobacterial (AM infection is caused by Mycobacterium species other than M.tuberculosis. AM skin infection has clinical manifestations that resemble M. tuberculosis infection and deep fungal infection. Laboratory workup is necessary to confirm the diagnosis. An 83-year old female came with a painful lump and swelling on her right lower extremity since three months before admission. Physical examination revealed a plaque consisting, of multiple erythematous and hyperpigmented papules and nodules, diffuse erythematous lesion, and shallow ulcers partially covered with pus and crust. Histopathological features showed tuberculoid granuloma. Direct test and periodic acid-Schiff (PAS staining of the skin biopsy found no fungal element nor acid-fast bacilli (AFB. Culture and polymerase chain reaction (PCR of M. tuberculosis were negative. The working diagnosis was atypical mycobacterial infection and treatment with 450 mg rifampicin and 100 mg minocycline daily were administered accordingly. In two months observation following the treatment, the pain was no longer exist, the ulcers were completely healed, and some nodules were in the process of healing Among other Mycobacterium spp, M.marinum is the most common cause of AM infrections. Clinical manifestation of M. marinum infection may present as solitary or multiple nodules on the hands, feet, elbows and knees with sporotrichoid spreading patern. The diagnosis of AM was established based on clinical and laboratory examination. The diagnosis was also confirmed by good clinical response to minocycline and rifampicin.

  4. Lung irradiation induces pulmonary vascular remodelling resembling pulmonary arterial hypertension.

    Science.gov (United States)

    Ghobadi, G; Bartelds, B; van der Veen, S J; Dickinson, M G; Brandenburg, S; Berger, R M F; Langendijk, J A; Coppes, R P; van Luijk, P

    2012-04-01

    Pulmonary arterial hypertension (PAH) is a commonly fatal pulmonary vascular disease that is often diagnosed late and is characterised by a progressive rise in pulmonary vascular resistance resulting from typical vascular remodelling. Recent data suggest that vascular damage plays an important role in the development of radiation-induced pulmonary toxicity. Therefore, the authors investigated whether irradiation of the lung also induces pulmonary hypertension. Different sub-volumes of the rat lung were irradiated with protons known to induce different levels of pulmonary vascular damage. Early loss of endothelial cells and vascular oedema were observed in the irradiation field and in shielded parts of the lung, even before the onset of clinical symptoms. 8 weeks after irradiation, irradiated volume-dependent vascular remodelling was observed, correlating perfectly with pulmonary artery pressure, right ventricle hypertrophy and pulmonary dysfunction. The findings indicate that partial lung irradiation induces pulmonary vascular remodelling resulting from acute pulmonary endothelial cell loss and consequential pulmonary hypertension. Moreover, the close resemblance of the observed vascular remodelling with vascular lesions in PAH makes partial lung irradiation a promising new model for studying PAH.

  5. Extended retroperitoneal necrotizing fasciitis with genital involvement, resembling fournier gangrene.

    Science.gov (United States)

    Sugimoto, Motokazu; Matsuura, Kenji; Takayama, Hiroshi; Kayo, Munefumi; Ie, Tomotsugu

    2010-10-01

    Necrotizing fasciitis is a serious infection that originates in the subcutaneous tissues. Although many reports have been published about necrotizing infections of other anatomical sites, retroperitoneal necrotizing soft tissue infection is a rare entity that has been described in only a few case reports. The etiology and clinical course of retroperitoneal necrotizing fasciitis can be variable and it is often difficult to identify the etiology of the infective process. We report a 58-year-old man with rapidly progressive, gas-producing, necrotizing inflammation in the retroperitoneum, complicated with genital involvement resembling Fournier gangrene. The patient was managed successfully by aggressive drainage, debridement, and sequential laparotomies to track and control the extensive necrosis of the retroperitoneum and perineum, in addition to systemic care to control sepsis. After his general condition stabilized, early rectosigmoid adenocarcinoma was identified and resected curatively. He remained well at follow up, six months after discharge. In retrospect, the trigger of the disease process was unclear. Although it was believed possibly to be due to the colon lesion, adenocarcinoma of the rectosigmoid colon was identified and the patient was managed successfully. Similar to necrotizing infections at other anatomical sites, early diagnosis and timely surgical intervention and systemic antimicrobial therapy are mandatory for treating patients with retroperitoneal necrotizing fasciitis.

  6. Neurogenesis in Aplysia californica resembles nervous system formation in vertebrates

    International Nuclear Information System (INIS)

    Jacob, M.H.

    1984-01-01

    The pattern of neurogenesis of the central nervous system of Aplysia californica was investigated by [ 3 H]thymidine autoradiography. Large numbers of animals at a series of early developmental stages were labeled with [ 3 H]thymidine for 24 or 48 hr and were subsequently sampled at specific intervals throughout the life cycle. I found that proliferative zones, consisting of columnar and placodal ectodermal cells, are established in regions of the body wall adjacent to underlying mesodermal cells. Mitosis in the proliferative zones generates a population of cells which leave the surface and migrate inward to join the nearby forming ganglia. Tracing specific [ 3 H]thymidine-labeled cells from the body wall to a particular ganglion and within the ganglion over time suggests that the final genomic replication of the neuronal precursors occurs before the cells join the ganglion while glial cell precursors and differentiating glial cells continue to divide within the ganglion for some time. Ultrastructural examination of the morphological features of the few mitosing cells observed within the Aplysia central nervous system supports this interpretation. The pattern of neurogenesis in the Aplysia central nervous system resembles the proliferation of cells in the neural tube and the migration of neural crest and ectodermal placode cells in the vertebrate nervous system but differs from the pattern described for other invertebrates

  7. Virtual Labs and Virtual Worlds

    Science.gov (United States)

    Boehler, Ted

    2006-12-01

    Virtual Labs and Virtual Worlds Coastline Community College has under development several virtual lab simulations and activities that range from biology, to language labs, to virtual discussion environments. Imagine a virtual world that students enter online, by logging onto their computer from home or anywhere they have web access. Upon entering this world they select a personalized identity represented by a digitized character (avatar) that can freely move about, interact with the environment, and communicate with other characters. In these virtual worlds, buildings, gathering places, conference rooms, labs, science rooms, and a variety of other “real world” elements are evident. When characters move about and encounter other people (players) they may freely communicate. They can examine things, manipulate objects, read signs, watch video clips, hear sounds, and jump to other locations. Goals of critical thinking, social interaction, peer collaboration, group support, and enhanced learning can be achieved in surprising new ways with this innovative approach to peer-to-peer communication in a virtual discussion world. In this presentation, short demos will be given of several online learning environments including a virtual biology lab, a marine science module, a Spanish lab, and a virtual discussion world. Coastline College has been a leader in the development of distance learning and media-based education for nearly 30 years and currently offers courses through PDA, Internet, DVD, CD-ROM, TV, and Videoconferencing technologies. Its distance learning program serves over 20,000 students every year. sponsor Jerry Meisner

  8. 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...

  9. Virtual Exploratories

    DEFF Research Database (Denmark)

    Jensen, Sisse Siggaard

    2006-01-01

    -systems, the paper introduces the designing strategy referred to as virtual exploratories. Some of the advanced virtual worlds may inspire the design of such provoking and challenging virtual exploratories, and especially the Massively Multi-User Online Role-Playing Games (MMORPGS). However, if we have to learn from...... the design and activity of the advanced virtual worlds and role-playing games, then the empirical research on the actors’ activity, while they are acting, is an important precondition to it. A step towards the conception of such a designing strategy for virtual exploratories is currently pursued......, the sense-making ontology and triangle (Dervin et al., 2003), the video-interaction analysis (Henderson & Jordan, 1994), and the method of videoviews (Jensen, 2001, 2005). Also the two analytical concepts ‘intermediaries’ and ‘mediators’ that come from the actor-network theory (Latour, 2005) are introduced...

  10. Do general radiographic examinations resemble a person-centred environment?

    International Nuclear Information System (INIS)

    Hayre, C.M.; Blackman, S.; Eyden, A.

    2016-01-01

    Aim and objective: It is argued whether general radiographic examinations adhere to a person-centred approach within the direct digital radiography (DDR) environment. General radiographic examinations continue to increase and constitute approximately 90% of all examinations undertaken in the clinical environment. This study explored the potential impact patients experience whilst undergoing general imaging examinations. Method: An ethnographic methodology provided insight of two general radiography environments in the United Kingdom (UK) using participant observation and semi-structured interviews. Findings: The findings highlighted an ‘in and out’ culture whereby patients are ‘hurried’ and ‘rushed’ out of X-ray rooms in response to increasing time pressures experienced by diagnostic radiographers. In addition, this study challenged that patients may begin to rank ‘speed’ and ‘waiting times’ above other elements of radiographic care thus presenting new challenges for radiographers within the clinical environment. Conclusion: It is asserted that radiographers should remain holistic healthcare professionals and not begin to resemble operators on the production line. Further, it challenges whether patients are beginning to rank aspects of radiographic care within contemporary practices. Advances in knowledge: Few studies have explored the radiographer–patient relationship within the DDR environment, yet this study provides insight of person-centred practices within contemporary practices. - Highlights: • Challenges whether the use of DDR conforms to a person-centred approach. • Challenges whether radiographers are ‘treating patients as persons’ using DDR. • Patients may begin to rank ‘speed’ and ‘waiting times’ above other aspects of radiographic care.

  11. Predator-Resembling Aversive Conditioning for Managing Habituated Wildlife

    Directory of Open Access Journals (Sweden)

    Elsabé Louise Kloppers

    2005-06-01

    Full Text Available Wildlife habituation near urban centers can disrupt natural ecological processes, destroy habitat, and threaten public safety. Consequently, management of habituated animals is typically invasive and often includes translocation of these animals to remote areas and sometimes even their destruction. Techniques to prevent or reverse habituation and other forms of in situ management are necessary to balance ecological and social requirements, but they have received very little experimental attention to date. This study compared the efficacy of two aversive conditioning treatments that used either humans or dogs to create sequences resembling chases by predators, which, along with a control category, were repeatedly and individually applied to 24 moderately habituated, radio-collared elk in Banff National Park during the winter of 2001-2002. Three response variables were measured before and after treatment. Relative to untreated animals, the distance at which elk fled from approaching humans, i.e., the flight response distance, increased following both human and dog treatments, but there was no difference between the two treatments. The proportion of time spent in vigilance postures decreased for all treatment groups, without differences among groups, suggesting that this behavior responded mainly to seasonal effects. The average distance between elk locations and the town boundary, measured once daily by telemetry, significantly increased for human-conditioned elk. One of the co-variates we measured, wolf activity, exerted counteracting effects on conditioning effects; flight response distances and proximity to the town site were both lower when wolf activity was high. This research demonstrates that it is possible to temporarily modify aspects of the behavior of moderately habituated elk using aversive conditioning, suggests a method for reducing habituation in the first place, and provides a solution for Banff and other jurisdictions to manage

  12. Gait analysis in a mouse model resembling Leigh disease.

    Science.gov (United States)

    de Haas, Ria; Russel, Frans G; Smeitink, Jan A

    2016-01-01

    Leigh disease (LD) is one of the clinical phenotypes of mitochondrial OXPHOS disorders and also known as sub-acute necrotizing encephalomyelopathy. The disease has an incidence of 1 in 77,000 live births. Symptoms typically begin early in life and prognosis for LD patients is poor. Currently, no clinically effective treatments are available. Suitable animal and cellular models are necessary for the understanding of the neuropathology and the development of successful new therapeutic strategies. In this study we used the Ndufs4 knockout (Ndufs4(-/-)) mouse, a model of mitochondrial complex I deficiency. Ndusf4(-/-) mice exhibit progressive neurodegeneration, which closely resemble the human LD phenotype. When dissecting behavioral abnormalities in animal models it is of great importance to apply translational tools that are clinically relevant. To distinguish gait abnormalities in patients, simple walking tests can be assessed, but in animals this is not easy. This study is the first to demonstrate automated CatWalk gait analysis in the Ndufs4(-/-) mouse model. Marked differences were noted between Ndufs4(-/-) and control mice in dynamic, static, coordination and support parameters. Variation of walking speed was significantly increased in Ndufs4(-/-) mice, suggesting hampered and uncoordinated gait. Furthermore, decreased regularity index, increased base of support and changes in support were noted in the Ndufs4(-/-) mice. Here, we report the ability of the CatWalk system to sensitively assess gait abnormalities in Ndufs4(-/-) mice. This objective gait analysis can be of great value for intervention and drug efficacy studies in animal models for mitochondrial disease. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Meurigite, a new fibrous iron phosphate resembling kidwellite

    Science.gov (United States)

    Birch, W.D.; Pring, A.; Self, P.G.; Gibbs, R.B.; Keck, E.; Jensen, M.C.; Foord, E.E.

    1996-01-01

    Meurigite is a new hydrated potassium iron phosphate related to kidwellite and with structural similarities to other late-stage fibrous ferric phosphate species. It has been found at four localities so far - the Santa Rita mine, New Mexico, U.S.A.; the Hagendorf-Sud pegmatite in Bavaria, Germany; granite pegmatite veins at Wycheproof, Victoria. Australia; and at the Gold Quarry Mine, Nevada, U.S.A. The Santa Rita mine is the designated type locality. Meurigite occurs as tabular, elongated crystals forming spherical and hemispherical clusters and drusy coatings. The colour ranges from creamy white to pale yellow and yellowish brown. At the type locality, the hemispheres may reach 2 mm across, but the maximum diameter reached in the other occurrences is usually less than 0.5 mm. A wide variety of secondary phosphate minerals accompanies meurigite at each locality, with dufrenite, cyrilovite. beraunite, rockbridgeite and leucophosphite amongst the most common. Vanadates and uranates occur with meurigite at the Gold Quarry mine. Electron microprobe analysis and separate determination of H2O and CO2 on meurigite from the type locality gave a composition for which several empirical formulae could be calculated. The preferred formula, obtained on the basis of 35 oxygen atoms, is (K0.85Na0.03)??0.88(Fe7.013+Al0.16Cu0.02)??7.19 (PO4)5.11(CO3)0.20(OH) 6.7??7-7.25H2O, which simplifies to KFe73+(PO4)5(OH) 7??8H2O. Qualitative analyses only were obtained for meurigite from the other localities, due to the softness and openness of the aggregates. Because of the fibrous nature of meurigite, it was not possible to determine the crystal structure, hence the exact stoichiometry remains uncertain. The lustre of meurigite varies from vitreous to waxy for the Santa Rita mine mineral, to silky for the more open sprays and internal surfaces elsewhere. The streak is very pale yellow to cream and the estimated Mohs hardness is about 3. Cleavage is perfect on {001] and fragments from the

  14. Virtual Savannah

    DEFF Research Database (Denmark)

    Eskildsen, Søren; Rodil, Kasper; Rehm, Matthias

    2012-01-01

    It is a daunting task to visualize square kilometers of African savannah and currently in zoos it is impossible to present true African ecology to visitors. Virtual Savannah is a dynamic virtual world that introduces school children to a 3D representation of the wildlife sanctuaries Serengeti...... and the navigation. The test depicted how they managed to search the virtual world for answers in patterns related to restrictions in the system and using graphical points of interest as reference points. Collecting information about the complete interaction provides teachers with a tool to assess the individual...

  15. Virtual care

    DEFF Research Database (Denmark)

    Kamp, Annette; Aaløkke Ballegaard, Stinne

    of retrenchment, promising better quality, empowerment of citizens and work that is smarter and more qualified. Through ethnographic field studies we study the introduction of virtual home care in Danish elderly care, focusing on the implications for relational work and care relations. Virtual home care entails...... and professionals, and they instigate change in organization and professional identities. Studies, which more specifically deal with telecare, stress how virtualization alters the character of the observations care workers are able to make, and how the validity of the patients’ own measurements and observations...... point out how issues of trust and surveillance, which are always negotiated in care relations, are in fact accentuated in this kind of virtual care work. Moreover, we stress that the contemporary institutional context, organization and time schedules have a vast impact on the practices developed....

  16. Virtual Savannah

    DEFF Research Database (Denmark)

    Eskildsen, Søren; Rodil, Kasper; Rehm, Matthias

    2012-01-01

    It is a daunting task to visualize square kilometers of African savannah and currently in zoos it is impossible to present true African ecology to visitors. Virtual Savannah is a dynamic virtual world that introduces school children to a 3D representation of the wildlife sanctuaries Serengeti...... and Masai Mara. The objective is to substitute supplementary textual information currently used in schools and provide the teacher with information about each pupil. The Virtual Savannah was tested in situ on 19 pupils age 10-11 with the purpose of logging all interaction with animals, GUI...... and the navigation. The test depicted how they managed to search the virtual world for answers in patterns related to restrictions in the system and using graphical points of interest as reference points. Collecting information about the complete interaction provides teachers with a tool to assess the individual...

  17. Virtual data

    International Nuclear Information System (INIS)

    Bjorklund, E.

    1993-01-01

    In the 1970's, when computers were memory limited, operating system designers created the concept of ''virtual memory'' which gave users the ability to address more memory than physically existed. In the 1990s, many large control systems have the potential for becoming data limited. We propose that many of the principles behind virtual memory systems (working sets, locality, caching, and clustering) can also be applied to data-limited systems - creating, in effect, ''virtual data systems.'' At the Los Alamos National Laboratory's Clinton P. Anderson Meson Physics Facility (LAMPF), we have applied these principles to a moderately sized (10,000 data points) data acquisition and control system. To test the principles, we measured the system's performance during tune-up, production, and maintenance periods. In this paper, we present a general discussion of the principles of a virtual data system along with some discussion of our own implementation and the results of our performance measurements

  18. Virtual Workshop

    DEFF Research Database (Denmark)

    Buus, Lillian; Bygholm, Ann

    In relation to the Tutor course in the Mediterranean Virtual University (MVU) project, a virtual workshop “Getting experiences with different synchronous communication media, collaboration, and group work” was held with all partner institutions in January 2006. More than 25 key-tutors within MVU...... participated from different institutions in the workshop. The result of the workshop was experiences with different communication tools and media. Facing the difficulties and possibilities in collaborateting virtually concerned around group work and development of a shared presentation. All based on getting...... experiences for the learning design of MVU courses. The workshop intented to give the participants the possibility to draw their own experiences with issues on computer supported collaboration, group work in a virtual environment, synchronous and asynchronous communication media, and different perspectives...

  19. Virtual Worlds for Virtual Organizing

    Science.gov (United States)

    Rhoten, Diana; Lutters, Wayne

    The members and resources of a virtual organization are dispersed across time and space, yet they function as a coherent entity through the use of technologies, networks, and alliances. As virtual organizations proliferate and become increasingly important in society, many may exploit the technical architecture s of virtual worlds, which are the confluence of computer-mediated communication, telepresence, and virtual reality originally created for gaming. A brief socio-technical history describes their early origins and the waves of progress followed by stasis that brought us to the current period of renewed enthusiasm. Examination of contemporary examples demonstrates how three genres of virtual worlds have enabled new arenas for virtual organizing: developer-defined closed worlds, user-modifiable quasi-open worlds, and user-generated open worlds. Among expected future trends are an increase in collaboration born virtually rather than imported from existing organizations, a tension between high-fidelity recreations of the physical world and hyper-stylized imaginations of fantasy worlds, and the growth of specialized worlds optimized for particular sectors, companies, or cultures.

  20. 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.

  1. 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

  2. The Origin of Spousal Resemblance for Alcohol Use Disorder.

    Science.gov (United States)

    Kendler, Kenneth S; Lönn, Sara Larsson; Salvatore, Jessica; Sundquist, Jan; Sundquist, Kristina

    2018-03-01

    Although spouses strongly resemble one another in their risk for alcohol use disorder (AUD), the causes of this association remain unclear. To examine longitudinally, in first marriages, the association of a first registration for AUD in one spouse with risk of registration in his or her partner and to explore changes in the risk for AUD registration in individuals with multiple marriages as they transition from a spouse with AUD to one without or vice versa. Population-wide Swedish registries were used to identify individuals born in Sweden between 1960 and 1990 who were married before the end of study follow-up on December 31, 2013. The study included 8562 marital pairs with no history of AUD registration prior to their first marriage and an AUD registration in 1 spouse during marriage and 4891 individuals with multiple marriages whose first spouse had no AUD registration and second spouse did or vice versa. Final statistical analyses were conducted from August 15 to September 1, 2017. A spousal onset or history of AUD registration. Alcohol use disorder registration in national medical, criminal, or pharmacy registries. Among the 8562 marital pairs (5883 female probands and 2679 male probands; mean [SD] age at marriage, 29.2 [5.7] years) in first marriages, the hazard ratio of AUD registration in wives immediately after the first AUD registration in their husbands was 13.82, which decreased 2 years later to 3.75. The hazard ratio of AUD registration in husbands after the first AUD registration in their wives was 9.21, which decreased 2 years later to 3.09. Among the 4891 individuals with multiple marriages (1439 women and 3452 men; mean [SD] age at first marriage, 25.5 [4.2] years), when individuals transitioned from a first marriage to a spouse with AUD to a second marriage to a spouse without AUD, the hazard ratio for AUD registration was 0.50 (95% CI, 0.42-0.59) in women and 0.51 (95% CI, 0.44-0.59) in men. After a first marriage to a spouse without AUD, the

  3. Virtual Tower

    International Nuclear Information System (INIS)

    Wayne, R.A.

    1997-01-01

    The primary responsibility of an intrusion detection system (IDS) operator is to monitor the system, assess alarms, and summon and coordinate the response team when a threat is acknowledged. The tools currently provided to the operator are somewhat limited: monitors must be switched, keystrokes must be entered to call up intrusion sensor data, and communication with the response force must be maintained. The Virtual tower is an operator interface assembled from low-cost commercial-off-the-shelf hardware and software; it enables large amounts of data to be displayed in a virtual manner that provides instant recognition for the operator and increases assessment accuracy in alarm annunciator and control systems. This is accomplished by correlating and fusing the data into a 360-degree visual representation that employs color, auxiliary attributes, video, and directional audio to prompt the operator. The Virtual Tower would be a valuable low-cost enhancement to existing systems

  4. Virtual Sustainability

    Directory of Open Access Journals (Sweden)

    William Sims Bainbridge

    2010-09-01

    Full Text Available In four ways, massively multiplayer online role-playing games may serve as tools for advancing sustainability goals, and as laboratories for developing alternatives to current social arrangements that have implications for the natural environment. First, by moving conspicuous consumption and other usually costly status competitions into virtual environments, these virtual worlds might reduce the need for physical resources. Second, they provide training that could prepare individuals to be teleworkers, and develop or demonstrate methods for using information technology to replace much transportation technology, notably in commuting. Third, virtual worlds and online games build international cooperation, even blending national cultures, thereby inching us toward not only the world consciousness needed for international agreements about the environment, but also toward non-spatial government that cuts across archaic nationalisms. Finally, realizing the potential social benefits of this new technology may urge us to reconsider a number of traditional societal institutions.

  5. Virtual toolbox

    Science.gov (United States)

    Jacobus, Charles J.; Jacobus, Heidi N.; Mitchell, Brian T.; Riggs, A. J.; Taylor, Mark J.

    1993-04-01

    At least three of the five senses must be fully addressed in a successful virtual reality (VR) system. Sight, sound, and touch are the most critical elements for the creation of the illusion of presence. Since humans depend so much on sight to collect information about their environment, this area has been the focus of much of the prior art in virtual reality, however, it is also crucial that we provide facilities for force, torque, and touch reflection, and sound replay and 3-D localization. In this paper we present a sampling of hardware and software in the virtual environment maker's `toolbox' which can support rapidly building up of customized VR systems. We provide demonstrative examples of how some of the tools work and we speculate about VR applications and future technology needs.

  6. Chemically controlled interfacial nanoparticle assembly into nanoporous gold films for electrochemical applications

    DEFF Research Database (Denmark)

    Christiansen, Mikkel U. -B.; Seselj, Nedjeljko; Engelbrekt, Christian

    2018-01-01

    at the liquid/air interface starting from gold nanoparticles (AuNPs) in an aqueous solution, providing silver-free gold films. Chloroauric acid is reduced to AuNP building blocks by 2-(N-morpholino)ethanesulfonic acid, which also acts as a protecting agent and pH buffer. By adding potassium chloride before Au......Nanoporous gold (NPG) is an effective material for electrocatalysis and can be made via a dealloy method such as etching of silver–gold alloys. Dealloyed NPG may contain residual silver that affects its catalytic performance. Herein, a different approach has been reported for the formation of NPG......NP synthesis and hydrochloric acid to the resultant AuNP solutions, we can reproducibly obtain continuous gold networks. The sintered AuNPs produced by this method result in chemically synthesized nanoporous gold films (cNPGFs) that resemble dealloyed NPG in terms of morphology and porosity; additionally...

  7. 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...

  8. Photo-Realistic Image Synthesis and Virtual Cinematography

    DEFF Research Database (Denmark)

    Livatino, Salvatore

    2005-01-01

    Realistic Virtual View Synthesis is a new field of research that has received increasing attention in recent years. It is strictly related to the grown popularity of virtual reality and the spread of its applications, among which virtual photography and cinematography. The use of computer generated...... characters, "virtual actors", in the motion picture production increases every day. While the most known computer graphics techniques have largely been adopted successfully in nowadays fictions, it still remains very challenging to implement virtual actors which would resemble, visually, human beings......: the augmented actor. Fundamental concepts and examples of methods proposed for realistic view synthesis based on the transfer of photo-realism from reference photographs to novel views, will be presented. The application of methods for realistic image synthesis to virtual cinematography will also be illustrated...

  9. Virtualize Me!

    Science.gov (United States)

    Waters, John K.

    2009-01-01

    John Abdelmalak, director of technology for the School District of the Chathams, was pretty sure it was time to jump on the virtualization bandwagon last year when he invited Dell to conduct a readiness assessment of his district's servers. When he saw just how little of their capacity was being used, he lost all doubt. Abdelmalak is one of many…

  10. Virtual patrolling.

    NARCIS (Netherlands)

    van der Vlist, M.; Wismans, Luc Johannes Josephus; van Beek, P.; Suijs, L.C.W.

    2016-01-01

    Approximately 25 per cent of all congestion on motorways is caused by incidents. By virtual patrolling, incidents e.g. queues, accidents and car breakdowns on a road network, can be predicted or detected in an early stage. This early detection and prediction of an incident likely to happen, offers

  11. Virtual patrolling

    NARCIS (Netherlands)

    van der Vlist, M.; Wismans, Luc Johannes Josephus; van Beek, P.; Suijs, L.C.W.

    2016-01-01

    Approximately 25 per cent of all congestion on motorways is caused by incidents. By virtual patrolling, incidents e.g. queues, accidents and car breakdowns on a road network, can be predicted or detected in an early stage. This early detection and prediction of an incident likely to happen, offers

  12. Virtual modeling

    NARCIS (Netherlands)

    Flores, J.; Kiss, S.; Cano, P.; Nijholt, Antinus; Zwiers, Jakob

    2003-01-01

    We concentrate our efforts on building virtual modelling environments where the content creator uses controls (widgets) as an interactive adjustment modality for the properties of the edited objects. Besides the advantage of being an on-line modelling approach (visualised just like any other on-line

  13. 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.

  14. 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

  15. 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.

  16. Sensorial Virtualization: Coupling Gaming and Virtual Environment

    NARCIS (Netherlands)

    Garbaya, S.; Miraoui, C.; Wendrich, Robert E.; Lim, T.; Stanescu, I.A.; Hauge, J.B.

    2014-01-01

    Virtual reality and virtualization are currently used to design complex systems and demonstrate that they represent the functionalities of real systems. However, the design refinement of the virtual environment (VE) and distributed virtual environment (DVE) are still time consuming and costly, as it

  17. Virtual anthropology.

    Science.gov (United States)

    Weber, Gerhard W

    2015-02-01

    Comparative morphology, dealing with the diversity of form and shape, and functional morphology, the study of the relationship between the structure and the function of an organism's parts, are both important subdisciplines in biological research. Virtual anthropology (VA) contributes to comparative morphology by taking advantage of technological innovations, and it also offers new opportunities for functional analyses. It exploits digital technologies and pools experts from different domains such as anthropology, primatology, medicine, paleontology, mathematics, statistics, computer science, and engineering. VA as a technical term was coined in the late 1990s from the perspective of anthropologists with the intent of being mostly applied to biological questions concerning recent and fossil hominoids. More generally, however, there are advanced methods to study shape and size or to manipulate data digitally suitable for application to all kinds of primates, mammals, other vertebrates, and invertebrates or to issues regarding plants, tools, or other objects. In this sense, we could also call the field "virtual morphology." The approach yields permanently available virtual copies of specimens and data that comprehensively quantify geometry, including previously neglected anatomical regions. It applies advanced statistical methods, supports the reconstruction of specimens based on reproducible manipulations, and promotes the acquisition of larger samples by data sharing via electronic archives. Finally, it can help identify new, hidden traits, which is particularly important in paleoanthropology, where the scarcity of material demands extracting information from fragmentary remains. This contribution presents a current view of the six main work steps of VA: digitize, expose, compare, reconstruct, materialize, and share. The VA machinery has also been successfully used in biomechanical studies which simulate the stress and strains appearing in structures. Although

  18. Virtual crimes

    OpenAIRE

    Pobořilová, Michaela

    2010-01-01

    Virtual crimes are a new specific area in the law system, which is associated with information technologies (mobile, Internet etc.). These are crimes that can be committed in cyberspace or in connection with it. Generally, cyberspace can be defined from different perspectives most often as social, technological and legal environment in which there is mutual interaction of its users. This environment, in particular the Internet, due to its characteristics such as unlimited local, speed, low co...

  19. Virtual Cystoscopy

    International Nuclear Information System (INIS)

    Mejia Restrepo, Jorge; Aldana S, Natalia; Munoz Sierra, Juan; Lopez Amaya, Juan

    2011-01-01

    Introduction: virtual cystoscopy is a minimally invasive procedure that facilitates the evaluation of the urinary tract, allowing intraluminal navigation through the urinary tract structures on the basis of CT imaging reconstructions. it allows detection of various pathologies of the system, through high-sensitivity, three-dimensional lesion visualization with some advantages over conventional cystoscopy. Objective: to describe the technique used for virtual cystoscopy at our institution,and present some representative cases. Materials and methods: We describe the main indications, advantages and limitations of the method, followed by a description of the technique used in our institution, and finally, we present five representative cases of bladder and urethral pathology. Conclusion: virtual cystoscopy is a sensitive technique for the diagnosis of bladder tumors, even those smaller than 5mm. it is the preferred method in patients who have contraindications for conventional cystoscopy, such as prostate hyperplasia, urethral stenoses and active haematuria.it is less invasive and has a lower complication rate when compared with conventional cystoscopy. It has limited use in the assessment of the mucosa and of small, flat lesions.

  20. Not all that glitters is gold - Electron microscopy study on uptake of gold nanoparticles in Daphnia magna and related artefacts

    DEFF Research Database (Denmark)

    Jensen, Louise Helene Søgaard; Skjolding, Lars Michael; Thit, Amalie

    2017-01-01

    techniques are used to investigate internalization of 10 nm gold nanoparticles in Daphnia magna gut lumen and gut epithelial cells upon 24h exposure and outline potential artefacts, i.e. high contract precipitates from sample preparation related to these techniques. Light sheet microscopy confirmed......, permitting only single particles through. Structures resembling nanoparticles were also observed inside gut cells. As elemental analysis could not verify these to be gold they were likely artifacts from the preparation, such as osmium and iron. Importantly, gold nanoparticles were in fact found inside...... holocrine cells with disrupted membranes. Thus, false positive observations of nanoparticle internalization may result from either preparation artefacts or by mistaking disrupted cells for intact. These findings emphasize the importance of cell integrity and combining elemental analysis...

  1. [Clustering analysis of karyotype resemblance-near coefficient for 6 Bupleurum species].

    Science.gov (United States)

    Song, Yun; Qiao, Yonggang; Wu, Yuxiang

    2012-04-01

    To explore the genetic evolutionary distance between plants by using karyotype parameters identification of medicinal plants. The cluster analysis of karyotype resemblance-near coefficient and evolutionary distance was used for 6 Bupleurum species. The results showed that there were the biggest karyotype resemblance-near coefficient (0.9920) and the smallest evolutionary distance (D(e) = 0.0080) between B. scorzonerifolium and B. chinense, indicating the closest relationship, and the minimum karyotype resemblance-near coefficient (0.4794) and the maximum evolutionary distance (D(e) = 0.7352) between B. smityii and B. falcatum, indicating the most distant relationship. Karyotype was an important parameter for identification of medicinal plants because karyotype was stabilized for species. The genetic distance between in 6 species of Bupleurum species was obtained by karyotype clustering analysis of karyotype resemblance-near coefficient. There was the bigger evolutionary distance between the species which had different chromosome number.

  2. Periodismo virtual

    Directory of Open Access Journals (Sweden)

    Carlos Morales

    2015-01-01

    Full Text Available El periodismo virtual se produce en diarios que no ofrecen noticias (concebidas como versión o reflejo de la realidad sino que crean sus propias ficciones, especialmente en primeras planas. El autor del artículo señala que esto esta sucediendo en LA NACIÓN de San José de Costa Rica, diario premiado por la inefable Sociedad Interamericana de Prensa - SIP - y periódico económicamente más importante del país.

  3. 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

  4. 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.

  5. 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

  6. 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....

  7. Realidad virtual y materialidad

    OpenAIRE

    Pérez Herranz, Fernando Miguel

    2009-01-01

    1. Fenomenología de partida: Real / Simbólico / Imaginario 2. Realidad 3. Virtual 3.1. Virtual / real / posible / probable 3.2. Los contextos de la realidad virtual A) REALIDAD VIRTUAL INMERSIVA B) REALIDAD VIRTUAL NO INMERSIVA C) REALIDAD VIRTUAL Y DIGITALIZACIÓN 3.3. Cruce virtual / real 3.4. Cuestiones filosóficas 4. Materialidad 5. Materialidad y descentramiento 5.1. Ejemplos de descentramiento en los contextos de Realidad Virtual A’) DUALISMO CARTESIANO, CUERPO Y «CIBORG » B’) EL ESPÍRIT...

  8. Virtual Touch

    DEFF Research Database (Denmark)

    Stenslie, Ståle

    The central focus of this thesis is the use and experience of touch in artistic, multimodal and computer-based environments. The haptic experience of touch is an area that has only received limited research-based interest. Touch is too often seen as the effect, and not the cause of our everyday...... experiences. The study aims to provide an improved knowledge of how touch functions and how haptic storytelling can be used as an artistic medium. This thesis is divided into seven parts. The introductory chapter presents the structure of the study and the history leading up the formulation of research...... Erotogod. The third chapter investigates the foundations of touch through a physiological and psychological approach. Chapter four presents an alternative haptic history of Virtual Realities through the presentation and discussion of several technological and artistic works that are computer...

  9. Realidad virtual

    OpenAIRE

    García García, Alberto Luis

    2000-01-01

    Las nuevas tecnologías, basadas en el mundo digital propuesto por la informática, están cambiando nuestra forma de entender el mundo, tanto desde el punto de vista sociocultural como económico. La realidad virtual se vale de códigos icónicos, y con ello se convierte en un paso más hacia la supresión de toda barrera linguística, para llegar a conseguir la gran comunidad global. Es necesario conocer en toda su extensión, una tecnología que está cambiando el modo de comunicarnos. Estos son, a gr...

  10. Atelier Virtual

    OpenAIRE

    Leite, Luzirene do Rego

    2007-01-01

    Esta dissertação trata da proposição de um atelier virtual que contribua para arte-educação a distância. A origem desta idéia foi definida no trabalho desenvolvido durante minha experiência no Grupo Arteduca, formado por professores que atuam no Instituto de Artes da Universidade de Brasília e, mais especificamente, no curso "Arteduca: Arte, Educação e Tecnologias Contemporâneas". O foco desta dissertação está direcionado para a produção artística em ambientes virtuais de aprendizagem, por me...

  11. From virtual environment to virtual community

    NARCIS (Netherlands)

    Nijholt, Antinus; Terano, Takao; Nishida, Toyoaki; Namatame, Akira; Tsumoto, Syusaku; Ohsawa, Yukido; Washio, Takashi

    2001-01-01

    We discuss a virtual reality theater environment and its transition to a virtual community by adding domain agents and by allowing multiple users to visit this environment. The environment has been built using VRML (Virtual Reality Modeling Language). We discuss how our ideas about this environment

  12. Microsoft Virtualization Master Microsoft Server, Desktop, Application, and Presentation Virtualization

    CERN Document Server

    Olzak, Thomas; Boomer, Jason; Keefer, Robert M

    2010-01-01

    Microsoft Virtualization helps you understand and implement the latest virtualization strategies available with Microsoft products. This book focuses on: Server Virtualization, Desktop Virtualization, Application Virtualization, and Presentation Virtualization. Whether you are managing Hyper-V, implementing desktop virtualization, or even migrating virtual machines, this book is packed with coverage on all aspects of these processes. Written by a talented team of Microsoft MVPs, Microsoft Virtualization is the leading resource for a full installation, migration, or integration of virtual syste

  13. 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...

  14. Evaluation of the appreciation of virtual teeth with and without pathology.

    Science.gov (United States)

    de Boer, I R; Lagerweij, M D; Wesselink, P R; Vervoorn, J M

    2015-05-01

    Virtual teeth with and without tooth pathology have been developed for use in a virtual learning environment in dental education. The objective of this study was to evaluate the appearance of these virtual teeth for use in dental education and to compare them with contemporary educational models, such as plastic teeth (Frasaco GmbH) and extracted human teeth. Six sets of photographs representing six different teeth were shown to dentists, teachers (dentists) and dental students (bachelor's and master's degree students). Each set consisted of 15 pictures showing five views of the extracted human tooth, the similar virtual tooth and the plastic tooth. The five views represented the mesial, distal, occlusal, buccal and lingual surfaces. The virtual tooth was the same as the extracted tooth (scanned with a cone beam CT, coloured and edited in ColorMapEditor(®) ), and the plastic tooth presented the best possible match to the extracted tooth. The participants were asked to rate the appearance of the virtual teeth (overall and in terms of caries, restoration and colours), whether the virtual or plastic teeth resembled the extracted teeth better and from which teeth they expected to learn the most (extracted, virtual or plastic). Each group of participants found that the virtual teeth resembled the extracted teeth more than they resembled the plastic teeth; 71% of the participants expected to learn more from the virtual teeth than from the plastic teeth. The results show that the appearance of the virtual teeth was considered more realistic than the appearance of the plastic teeth. The expectation was that the learning opportunities of the virtual teeth are better than of the plastic teeth. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. MRI findings of uterine tumor resembling ovarian sex-cord tumor: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Sung Hwan; Kim, Hee Jin; Han, Hyun Young; Hwang, In Taek; Kim, Ju Heon; Lee, Seung Yeon [Eulji University Hospital, Eulji University School of Medicine, Daejeon (Korea, Republic of)

    2017-04-15

    Uterine tumor resembling ovarian sex-cord tumor is a very rare uterine neoplasm that was first described by Clement and Scully in 1976. Since then, approximately 70 cases have been reported. However, these case reports have mainly described and discussed the pathologic and clinical features, and few radiologic findings have been presented. We experienced a case of a uterine tumor resembling ovarian sex-cord tumor, which was considered a uterine leiomyoma or leiomyosarcoma upon initial impression at preoperative evaluation including transvaginal ultrasonography and pelvic magnetic resonance imaging. Its diagnosis was pathologically confirmed after total abdominal hysterectomy.

  16. 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.

  17. Virtual reality in education

    OpenAIRE

    Minocha, Shailey; Tudor, Ana-Despina

    2017-01-01

    In this workshop-presentation, we described the evolution of virtual reality technologies and our research from 3D virtual worlds, 3D virtual environments built in gaming environments such as Unity 3D, 360-degree videos, and mobile virtual reality via Google Expeditions. For each of these four technologies, we discussed the affordances of the technologies and how they contribute towards learning and teaching. We outlined the significance of students being aware of the different virtual realit...

  18. Virtual reality - aesthetic consequences

    OpenAIRE

    Benda, Lubor

    2014-01-01

    In the present work we study aesthetic consequences of virtual reality. Exploring the fringe between fictional and virtual is one of the key goals, that will be achieved through etymologic and technologic definition of both fiction and virtual reality, fictional and virtual worlds. Both fiction and virtual reality will be then studied from aesthetic distance and aesthetic pleasure point of view. At the end, we will see the main difference as well as an common grounds between fiction and virtu...

  19. Muscle-type nicotinic receptor modulation by 2,6-dimethylaniline, a molecule resembling the hydrophobic moiety of lidocaine

    Directory of Open Access Journals (Sweden)

    Armando Alberola-Die

    2016-11-01

    Full Text Available To identify the molecular determinants responsible for lidocaine blockade of muscle-type nAChRs, we have studied the effects on this receptor of 2,6-dimethylaniline (DMA, which resembles lidocaine’s hydrophobic moiety. Torpedo marmorata nAChRs were microtransplanted to Xenopus oocytes and currents elicited by ACh (IACh, either alone or co-applied with DMA, were recorded. DMA reversibly blocked IACh and, similarly to lidocaine, exerted a closed-channel blockade, as evidenced by the enhancement of IACh blockade when DMA was pre-applied before its co-application with ACh, and hastened IACh decay. However, there were marked differences among its mechanisms of nAChR inhibition and those mediated by either the entire lidocaine molecule or diethylamine (DEA, a small amine resembling lidocaine’s hydrophilic moiety. Thereby, the IC50 for DMA, estimated from the dose-inhibition curve, was in the millimolar range, which is one order of magnitude higher than that for either DEA or lidocaine. Besides, nAChR blockade by DMA was voltage-independent in contrast to the increase of IACh inhibition at negative potentials caused by the more polar lidocaine or DEA molecules. Accordingly, virtual docking assays of DMA on nAChRs showed that this molecule binds predominantly at intersubunit crevices of the transmembrane-spanning domain, but also at the extracellular domain. Furthermore, DMA interacted with residues inside the channel pore, although only in the open-channel conformation. Interestingly, co-application of ACh with DEA and DMA, at their IC50s, had additive inhibitory effects on IACh and the extent of blockade was similar to that predicted by the allotopic model of interaction, suggesting that DEA and DMA bind to nAChRs at different loci. These results indicate that DMA mainly mimics the low potency and non-competitive actions of lidocaine on nAChRs, as opposed to the high potency and voltage-dependent block by lidocaine, which is emulated by the

  20. 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

  1. 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...

  2. Schwannoma of the Lower Eyelid Resembling a Recurrent Chalazion : A Case Report

    OpenAIRE

    Fukuyama, Junichiro; Hayasaka, Seiji; Setogawa, Tomoichi

    1990-01-01

    A 55-year-old man complained of foreign body sensation and a solid mass in the lower eyelid of the right eye. Clinically, the lesion resembled a chalazion, and it was excised. Histopathologic examination of the excised specimen revealed a schwannoma (neurilemmoma). We believe that this is a rare case of a schwannoma of the lower eyelid simulating a chalazion.

  3. Family resemblance in fat intake, nutrition attitudes and beliefs : a study among three generations of women

    NARCIS (Netherlands)

    Stafleu, A.

    1994-01-01

    In this thesis nutrition attitudes, beliefs, and fat intake in three generations of women are described. The aim of the study was twofold: the development of methods, and to study family resemblance in food habits. Based on literature study and qualitative pilot studies a questionnaire on

  4. Resemblances of Parents and Twins in Sport Participation and Heart Rate

    NARCIS (Netherlands)

    Boomsma, D.I.; van den Bree, M.B.; Orlebeke, J.F.; Molenaar, P.C.M.

    1989-01-01

    A model to analyze resemblances of twins and parents using LISREL is outlined and applied to sports participation and heart-rate data. Sports participation and heart rate were measured in 44 monozygotic and 46 dizygotic adolescent twin pairs and in their parents. Genetic factors influence variation

  5. Startle eye-blink modulation by facial self-resemblance and current mood.

    Science.gov (United States)

    Finke, Johannes B; Larra, Mauro F; Schilling, Thomas M; Lass-Hennemann, Johanna; Blumenthal, Terry D; Schächinger, Hartmut

    2015-06-01

    Although salient stimuli are known to modulate startle eye-blink responses, and one's own face is considered of particular salience, effects of facial self-resemblance on startle responsiveness have not been systematically investigated. For the present study, pictures from the FACES database (rated as neutral) were digitally morphed to resemble the participants' (N=37) faces to varying degrees (25-50-75%). Perceptually matched geometrical shapes served as a control condition. At SOAs of either 300ms or 3000ms after picture onset, startle responses were elicited by white noise (50ms, 105dB), and recorded at the orbicularis oculi via EMG. Prior to the experiment, self-reported mood was assessed by means of the PANAS. Relative to non-face stimuli, the presentation of faces reduced startle magnitude at short, but not long, lead intervals. Furthermore, for probes presented at a SOA of 300ms, a linear decrease in startle magnitude with higher levels of self-resemblance was observed, presumably reflecting higher salience of the self-face. The startle modulating effect of self-resembling faces during longer lead intervals was moderated by the participants' current mood: negative affect predicted stronger patterns of attenuation, which might be interpreted as an increase in self-focus resulting from more negative mood. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Familial neurofibromatosis type 1 associated with an overgrowth syndrome resembling Weaver syndrome

    NARCIS (Netherlands)

    van Asperen, C. J.; Overweg-Plandsoen, W. C.; Cnossen, M. H.; van Tijn, D. A.; Hennekam, R. C.

    1998-01-01

    The simultaneous occurrence of familial neurofibromatosis type 1 (NF1) and an overgrowth syndrome resembling Weaver syndrome was observed in two related cases (a mother and her son). NF1 was confirmed by molecular genetic analysis showing a large deletion at 17q11.2, encompassing the entire NF1

  7. Descriptive Understandings of the Nature of Science: Examining the Consensual and Family Resemblance Approaches

    Science.gov (United States)

    do Nascimento Rocha, Maristela; Gurgel, Ivã

    2017-01-01

    This paper performs a critical analysis of the consensual and family resemblance approaches to the nature of science. Despite the debate that surrounds them, between a pragmatic consensus and a more comprehensive understanding, both approaches have in common the goal of helping students to "internalize" knowledge about science in a…

  8. Central nervous system and vertebral malformation resembling the Arnold-Chiari syndrome in a Simmental calf.

    OpenAIRE

    LeClerc, S; López, A; Illanes, O

    1997-01-01

    Multiple congenital anomalies were identified in a stillborn calf, including severe cerebellar hypoplasia and central nervous system abnormalities resembling the Arnold-Chiari syndrome of malformation of calves. The Arnold-Chiari malformation occurs sporadically and has little economic impact, whereas cerebellar hypoplasia implies the presence of BVD virus in the herd.

  9. Central nervous system and vertebral malformation resembling the Arnold-Chiari syndrome in a Simmental calf.

    Science.gov (United States)

    LeClerc, S; López, A; Illanes, O

    1997-01-01

    Multiple congenital anomalies were identified in a stillborn calf, including severe cerebellar hypoplasia and central nervous system abnormalities resembling the Arnold-Chiari syndrome of malformation of calves. The Arnold-Chiari malformation occurs sporadically and has little economic impact, whereas cerebellar hypoplasia implies the presence of BVD virus in the herd. Images Figure 1. PMID:9167880

  10. Virtual Goods Recommendations in Virtual Worlds

    Directory of Open Access Journals (Sweden)

    Kuan-Yu Chen

    2015-01-01

    Full Text Available Virtual worlds (VWs are computer-simulated environments which allow users to create their own virtual character as an avatar. With the rapidly growing user volume in VWs, platform providers launch virtual goods in haste and stampede users to increase sales revenue. However, the rapidity of development incurs virtual unrelated items which will be difficult to remarket. It not only wastes virtual global companies’ intelligence resources, but also makes it difficult for users to find suitable virtual goods fit for their virtual home in daily virtual life. In the VWs, users decorate their houses, visit others’ homes, create families, host parties, and so forth. Users establish their social life circles through these activities. This research proposes a novel virtual goods recommendation method based on these social interactions. The contact strength and contact influence result from interactions with social neighbors and influence users’ buying intention. Our research highlights the importance of social interactions in virtual goods recommendation. The experiment’s data were retrieved from an online VW platform, and the results show that the proposed method, considering social interactions and social life circle, has better performance than existing recommendation methods.

  11. ['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

  12. 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)

  13. 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…

  14. 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...

  15. 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.

  16. 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.

  17. Virtual Trackballs Revisited

    DEFF Research Database (Denmark)

    Henriksen, Knud; Sporring, Jon; Hornbæk, Kasper

    2004-01-01

    Rotation of three-dimensional objects by a two-dimensional mouse is a typical task in computer-aided design, operation simulations, and desktop virtual reality. The most commonly used rotation technique is a virtual trackball surrounding the object and operated by the mouse pointer. This article...... reviews and provides a mathematical foundation for virtual trackballs. The first, but still popular, virtual trackball was described by Chen et al. [CHECK END OF SENTENCE]. We show that the virtual trackball by Chen et al. does not rotate the object along the intended great circular arc on the virtual...... trackball and we give a correction. Another popular virtual trackball is Shoemake's quaternion implementation [CHECK END OF SENTENCE], which we show to be a special case of the virtual trackball by Chen et al.. Shoemake extends the scope of the virtual trackball to the full screen. Unfortunately, Shoemake...

  18. 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...

  19. 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

  20. 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

  1. 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

  2. Gastrointestinal symptoms resembling ulcerative proctitis caused by larvae of the drone fly Eristalis tenax.

    Science.gov (United States)

    Desoubeaux, Guillaume; Gaillard, Julien; Borée-Moreau, Diane; Bailly, Éric; Andres, Christian R; Chandenier, Jacques

    2014-04-01

    We report a case of facultative intestinal myiasis due to larvae of the drone fly Eristalis tenax, also named the rat-tailed maggots. The development of larvae in the lower bowel was responsible for non-specific gastrointestinal symptoms that resembled ulcerative proctitis. The diagnosis was established upon the observation of four spontaneously excreted mobile larvae. The definite identification of the E. tenax species was made possible by scanning electron microscopy. The clinical outcome was satisfactory.

  3. Corticomedullary mixed tumour resembling a small adrenal gland-involvement of cancer stem cells: case report

    OpenAIRE

    Duan, Lian; Fang, Fang; Fu, Wanlei; Fang, Zhenqiang; Wang, Hui; Yu, Shicang; Tang, Zili; Liu, Zhenqi; Zheng, Hongting

    2017-01-01

    Background Adrenal corticomedullary mixed tumours are very rare. Its mechanism is rarely reported. Here we report the first case of a corticomedullary mixed tumour resembling a ?small adrenal gland? with distinct arrangement of the cortical and medullary layers. We further hypothesize regarding the tumorigenic mechanism of this tumour. Case presentation A 58-year man had been diagnosed with diabetes and hypertension for 3?years. His 24-h urine vanillylmandelic acid (VMA) levels were slightly ...

  4. Which Football Player Bears Most Resemblance to Messi? A Statistical Analysis

    OpenAIRE

    Mazurek, Jiri

    2018-01-01

    Many pundits and fans ask themselves the same question: Which football player bears most resemblance to Lionel Messi? Is it Chelsea's Eden Hazard? Is it Paulo Dybala, the heir to Messi in the national team of Argentina? Or is the most alike player to Messi someone completely else? In general, the research on the evaluation of players' performances originated in the context of baseball in the USA, but, currently, it is of great importance in almost every team sport on the planet. Specifically,...

  5. Facial Resemblance Exaggerates Sex-Specific Jealousy-Based Decisions1

    Directory of Open Access Journals (Sweden)

    Steven M. Platek

    2007-01-01

    Full Text Available Sex differences in reaction to a romantic partner's infidelity are well documented and are hypothesized to be attributable to sex-specific jealousy mechanisms which are utilized to solve adaptive problems associated with risk of extra-pair copulation. Males, because of the risk of cuckoldry become more upset by sexual infidelity, while females, because of loss of resources and biparental investment tend to become more distressed by emotional infidelity. However, the degree to which these sex-specific reactions to jealousy interact with cues to kin are completely unknown. Here we investigated the interaction of facial resemblance with decisions about sex-specific jealousy scenarios. Fifty nine volunteers were asked to imagine that two different people (represented by facial composites informed them about their romantic partner's sexual or emotional infidelity. Consistent with previous research, males ranked sexual infidelity scenarios as most upsetting and females ranked emotional infidelity scenarios most upsetting. However, when information about the infidelity was provided by a face that resembled the subject, sex-specific reactions to jealousy were exaggerated. This finding highlights the use of facial resemblance as a putative self-referent phenotypic matching cue that impacts trusting behavior in sexual contexts.

  6. Virtual Trackballs Revisited

    OpenAIRE

    Henriksen, Knud; Sporring, Jon; Hornbæk, Kasper

    2004-01-01

    Udgivelsesdato: March/April Rotation of three-dimensional objects by a two-dimensional mouse is a typical task in computer-aided design, operation simulations, and desktop virtual reality. The most commonly used rotation technique is a virtual trackball surrounding the object and operated by the mouse pointer. This article reviews and provides a mathematical foundation for virtual trackballs. The first, but still popular, virtual trackball was described by Chen et al. [CHECK END OF SENTENC...

  7. Server virtualization solutions

    OpenAIRE

    Lodziņš, Gunārs Ernests

    2007-01-01

    Currently in the information technology sector that is responsible for a server infrastructure is a huge development in the field of server virtualization on x86 computer architecture. As a prerequisite for such a virtualization development is growth in server productivity and underutilization of available computing power. Several companies in the market are working on two virtualization architectures – hypervizor and hosting. In this paper several of virtualization products that use host...

  8. Virtual reality exposure therapy

    OpenAIRE

    Rothbaum, BO; Hodges, L; Kooper, R

    1997-01-01

    It has been proposed that virtual reality (VR) exposure may be an alternative to standard in vivo exposure. Virtual reality integrates real-time computer graphics, body tracking devices, visual displays, and other sensory input devices to immerse a participant in a computer- generated virtual environment. Virtual reality exposure is potentially an efficient and cost-effective treatment of anxiety disorders. VR exposure therapy reduced the fear of heights in the first control...

  9. Designing Virtual Worlds

    DEFF Research Database (Denmark)

    Gürsimsek, Remzi Ates

    2014-01-01

    mediators in 3D virtual space to collaborate and co-design the digital content. These co-designers are also the residents of these worlds, as they socialize by building inworld friendships. This article presents a social semiotic analysis of the three-dimensional virtual places and artifacts in the virtual...... the audio-visual characteristics of designing in multi-user virtual environments generate experiential, interpersonal and textual meaning potentials....

  10. Can virtual reality exposure therapy gains be generalized to real-life? : A meta-analysis of studies applying behavioral assessments

    NARCIS (Netherlands)

    Morina, Nexhmedin; Ijntema, Hiske; Meyerbröker, Katharina; Emmelkamp, Paul M G

    2015-01-01

    In virtual reality exposure therapy (VRET), patients are exposed to virtual environments that resemble feared real-life situations. The aim of the current study was to assess the extent to which VRET gains can be observed in real-life situations. We conducted a meta-analysis of clinical trials

  11. 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.)

  12. 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.

  13. 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

  14. Comparison between virtual museums

    Directory of Open Access Journals (Sweden)

    Simona Caraceni

    2014-04-01

    Full Text Available Drawing a taxonomy of virtual museum, that can fit to represent all the known cases of virtual museum in the last years, I tried to try my meta-model of classification in two very different examples of virtual museums, to prove the validity of my taxonomical meta-model.

  15. High availability using virtualization

    Science.gov (United States)

    Calzolari, Federico

    2009-10-01

    High availability has always been one of the main problems for a data center. Till now high availability was achieved by host per host redundancy, a highly expensive method in terms of hardware and human costs. A new approach to the problem can be offered by virtualization. Using virtualization, it is possible to achieve a redundancy system for all the services running on a data center. This new approach to high availability allows to share the running virtual machines over the servers up and running, by exploiting the features of the virtualization layer: start, stop and move virtual machines between physical hosts. The system (3RC) is based on a finite state machine with hysteresis, providing the possibility to restart each virtual machine over any physical host, or reinstall it from scratch. A complete infrastructure has been developed to install operating system and middleware in a few minutes. To virtualize the main servers of a data center, a new procedure has been developed to migrate physical to virtual hosts. The whole Grid data center SNS-PISA is running at the moment in virtual environment under the high availability system. As extension of the 3RC architecture, several storage solutions have been tested to store and centralize all the virtual disks, from NAS to SAN, to grant data safety and access from everywhere. Exploiting virtualization and ability to automatically reinstall a host, we provide a sort of host on-demand, where the action on a virtual machine is performed only when a disaster occurs.

  16. A Virtual Class Calculus

    DEFF Research Database (Denmark)

    Ernst, Erik; Ostermann, Klaus; Cook, William Randall

    2006-01-01

    model for virtual classes has been a long-standing open question. This paper presents a virtual class calculus, vc, that captures the essence of virtual classes in these full-fledged programming languages. The key contributions of the paper are a formalization of the dynamic and static semantics of vc...

  17. Gold-catalyzed cyclization reactions of allenol and alkynol derivatives.

    Science.gov (United States)

    Alcaide, Benito; Almendros, Pedro

    2014-03-18

    products) and 1,3-oxazin-2-one derivatives (thermodynamically favored) from easily accessible allenic carbamates. In addition, we discuss the direct gold-catalyzed cycloketalization of alkynyldioxolanes, as well as aminoketalization of alkynyloxazolidines. We performed labeling studies and density functional calculations to gain insight into the mechanisms of the bis-heterocyclization reactions. We also describe the controlled gold-catalyzed reactions of primary and secondary propargylic hydroperoxides with a variety of nucleophiles including alcohols and phenols, allowing the direct synthesis of β-functionalized ketones. Through computations and (18)O-labeling experiments, we discovered various aspects of the controlled reactivity of propargylic hydroperoxides with external nucleophiles under gold catalysis. The mechanism resembles a Meyer-Schuster rearrangement, but notably, the presence and geometry characteristics of the OOH functional group allow a new pathway to happen, which cannot apply to propargylic alcohols.

  18. Transport-related mylonitic ductile deformation and shape change of alluvial gold, southern New Zealand

    Science.gov (United States)

    Kerr, Gemma; Falconer, Donna; Reith, Frank; Craw, Dave

    2017-11-01

    Gold is a malleable metal, and detrital gold particles deform via internal distortion. The shapes of gold particles are commonly used to estimate transport distances from sources, but the mechanisms of internal gold deformation leading to shape changes are poorly understood because of subsequent recrystallisation of the gold in situ in placer deposits, which creates a rim zone around the particles, with undeformed > 10 μm grains. This paper describes samples from southern New Zealand in which grain size reduction (to submicrometer scale) and mylonitic textures have resulted from internal ductile deformation. These textures have been preserved without subsequent recrystallisation after deposition in late Pleistocene-Holocene alluvial fan placers. These mylonitic textures were imposed by transport-related deformation on recrystallised rims that were derived from previous stages of fluvial transportation and deposition. This latest stage of fluvial transport and deformation has produced numerous elongated gold smears that are typically 100 μm long and 10-20 μm wide. These smears are the principal agents for transport-induced changes in particle shape in the studied placers. Focused ion beam (FIB) sectioning through these deformed zones combined with scanning electron microscopic (SEM) imaging show that the interior of the gold particles has undergone grain size reduction (to 500 nm) and extensive folding with development of a ductile deformation fabric that resembles textures typical of mylonites in silicate rocks. Relict pods of the pre-existing recrystallised rim zone are floating in this ductile deformation zone and these pods are irregular in shape and discontinuous in three dimensions. Micrometer scale biologically-mediated deposition from groundwater of overgrowth gold on particle surfaces occurs at all stages of placer formation, and some of this overgrowth gold has been incorporated into deformation zones. These examples provide a rare view into the nature

  19. 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.

  20. METRIC OF VIRTUAL WORLDS

    OpenAIRE

    Trunev A. P.

    2013-01-01

    We investigate the hypothesis of a plurality of parallel and virtual worlds. It is assumed that sentient beings in each virtual world reach a stage of development that can create a virtual world to simulate the history of their own development. In this case, the virtual worlds are nested within each other, which put a severe restriction on the possible geometry of space-time. Discussed the draft geometry virtual worlds consistently displayed from one world to another. It is shown that in this...

  1. Virtualization A Manager's Guide

    CERN Document Server

    Kusnetzky, Dan

    2011-01-01

    What exactly is virtualization? As this concise book explains, virtualization is a smorgasbord of technologies that offer organizations many advantages, whether you're managing extremely large stores of rapidly changing data, scaling out an application, or harnessing huge amounts of computational power. With this guide, you get an overview of the five main types of virtualization technology, along with information on security, management, and modern use cases. Topics include: Access virtualization-Allows access to any application from any deviceApplication virtualization-Enables applications

  2. 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...

  3. 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.

  4. 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.

  5. Resembling a viper: implications of mimicry for conservation of the endangered smooth snake.

    Science.gov (United States)

    Valkonen, Janne K; Mappes, Johanna

    2014-12-01

    The phenomenon of Batesian mimicry, where a palatable animal gains protection against predation by resembling an unpalatable model, has been a core interest of evolutionary biologists for 150 years. An extensive range of studies has focused on revealing mechanistic aspects of mimicry (shared education and generalization of predators) and the evolutionary dynamics of mimicry systems (co-operation vs. conflict) and revealed that protective mimicry is widespread and is important for individual fitness. However, according to our knowledge, there are no case studies where mimicry theories have been applied to conservation of mimetic species. Theoretically, mimicry affects, for example, frequency dependency of predator avoidance learning and human induced mortality. We examined the case of the protected, endangered, nonvenomous smooth snake (Coronella austriaca) that mimics the nonprotected venomous adder (Vipera berus), both of which occur in the Åland archipelago, Finland. To quantify the added predation risk on smooth snakes caused by the rarity of vipers, we calculated risk estimates from experimental data. Resemblance of vipers enhances survival of smooth snakes against bird predation because many predators avoid touching venomous vipers. Mimetic resemblance is however disadvantageous against human predators, who kill venomous vipers and accidentally kill endangered, protected smooth snakes. We found that the effective population size of the adders in Åland is very low relative to its smooth snake mimic (28.93 and 41.35, respectively).Because Batesian mimicry is advantageous for the mimic only if model species exist in sufficiently high numbers, it is likely that the conservation program for smooth snakes will fail if adders continue to be destroyed. Understanding the population consequences of mimetic species may be crucial to the success of endangered species conservation. We suggest that when a Batesian mimic requires protection, conservation planners should

  6. Rupture Resemblance Score (RRS): toward risk stratification of unruptured intracranial aneurysms using hemodynamic-morphological discriminants.

    Science.gov (United States)

    Xiang, Jianping; Yu, Jihnhee; Choi, Hoon; Dolan Fox, Jennifer M; Snyder, Kenneth V; Levy, Elad I; Siddiqui, Adnan H; Meng, Hui

    2015-07-01

    We have previously developed three logistic regression models for discriminating intracranial aneurysm rupture status from 119 aneurysms based on hemodynamic-morphological parameters. In this study we exploit their use as a tool for predicting the risk of rupture of aneurysms with a defined Rupture Resemblance Score (RRS). We collected three-dimensional images of 85 consecutive aneurysms, applied the three regression models and compared model performance at predicting rupture status against anecdotal metrics (aneurysm size and aspect ratio). We then reinterpreted the model-predicted probability as RRS, where the higher the score the closer the resemblance to previously known rupture components, and applied the RRS prospectively to four unruptured aneurysms with borderline treatment decisions. All three models yielded excellent sensitivity (0.78-0.83) and specificity (0.78-0.84) at a cutoff score of 50%, whereas aneurysm size and aspect ratio showed poor sensitivities (0.28 and 0.33, respectively). Lowering the cutoff score to 30% improved sensitivity to 0.90. The RRS identified most of the ruptured aneurysms and also some unruptured ones that closely resembled ruptured aneurysms hemodynamically and/or morphologically. The prospective application of the RRS to unruptured aneurysms shows that it could provide additional insights for treatment decisions. Previous regression models based on hemodynamic-morphological parameters are able to discriminate rupture in a new cohort in the same population. A higher probability of rupture is associated with larger size ratio, lower normalized wall shear stress and higher oscillatory shear index. The RRS could potentially stratify rupture risk and assist in treatment decision-making for unruptured aneurysms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  7. 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.

  8. 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

  9. 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.

  10. A Drosophila gene encoding a protein resembling the human β-amyloid protein precursor

    International Nuclear Information System (INIS)

    Rosen, D.R.; Martin-Morris, L.; Luo, L.; White, K.

    1989-01-01

    The authors have isolated genomic and cDNA clones for a Drosophila gene resembling the human β-amyloid precursor protein (APP). This gene produces a nervous system-enriched 6.5-kilobase transcript. Sequencing of cDNAs derived from the 6.5-kilobase transcript predicts an 886-amino acid polypeptide. This polypeptide contains a putative transmembrane domain and exhibits strong sequence similarity to cytoplasmic and extracellular regions of the human β-amyloid precursor protein. There is a high probability that this Drosophila gene corresponds to the essential Drosophila locus vnd, a gene required for embryonic nervous system development

  11. Charge on luminous bodies resembling natural ball lightning produced via electrical arcs through lump silicon

    Science.gov (United States)

    Porter, Christina L.; Miley, Galen P.; Griffiths, David J.; Sánchez, Erik

    2014-12-01

    A phenomenon resembling natural ball lightning can be produced via electrical arcing through silicon. We use lump silicon instead of silicon wafers to achieve higher production rates and larger, longer-lived luminous balls than previously reported. The luminous balls consist of a silicon core surrounded by a porous network of loosely bound silicon dioxide nanoparticles. We find that the balls carry a small net charge on the order of 10-12 C and propose that the nanoparticles are electrostatically bound to the core due to this charge.

  12. Consolation in the aftermath of robberies resembles post-aggression consolation in chimpanzees

    DEFF Research Database (Denmark)

    Lindegaard, Marie Rosenkrantz; Liebst, Lasse Suonperä; Bernasco, Wim

    2017-01-01

    Post-aggression consolation is assumed to occur in humans as well as in chimpanzees. While consolation following peer aggression has been observed in children, systematic evidence of consolation in human adults is rare. We used surveillance camera footage of the immediate aftermath of nonfatal...... to be consoled. Furthermore, we show that high levels of threat during the robbery increased the likelihood of receiving consolation afterwards. These patterns resemble post-aggression consolation in chimpanzees and suggest that emotions of empathic concern are involved in consolation across humans...... and chimpanzees....

  13. A case of secondary syphilis with HIV, resembling borderline lepromatous leprosy

    Science.gov (United States)

    Mani, Mohan Zachariah; Kanish, Bimal; Kwatra, Kanwardeep; Chaudhary, Paulina R.; Bhatia, Anuradha

    2015-01-01

    We are reporting an unusual case of secondary syphilis, in a homosexual male patient, which resembled borderline lepromatous leprosy, and in whom the diagnosis was considered on clinical grounds. The patient also had concomitant HIV infection, with asymptomatic neurosyphilis. His rapid plasma reagin test was reactive in 1:128 dilution. He improved with three standard, weekly injections of benzathine penicillin, along with 2 g of intravenous ceftriaxone daily for 15 days. This case is being reported to highlight the need for a high index of suspicion in diagnosing unusual cases of secondary syphilis, especially in those with concomitant HIV infection. PMID:26692613

  14. 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)

  15. 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...

  16. 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 ...

  17. Virtual Reality: Principles and Applications

    OpenAIRE

    MÉRIENNE , Frédéric

    2017-01-01

    Virtual reality aims at immersing a user in a virtual environment. Dedicated virtual reality technologies of human–computer interaction enable to make the link between the user and a virtual environment in capturing the user’s motion, acting on his senses as well as computing the virtual experience in real-time. The immersion in virtual environment is evaluated through the user’s perception and reaction. Virtual reality is used in a large variety of application domains which need multisensory...

  18. Towards an improved Global Antioxidant Response method (GAR+): Physiological-resembling in vitro antioxidant capacity methods.

    Science.gov (United States)

    Pérez-Burillo, S; Rufián-Henares, J A; Pastoriza, S

    2018-01-15

    Many methods have been developed to measure the antioxidant capacity of foods under non physiological-relevant conditions. In this study, three methods (TEAC OH , GEAC RED and TEAC AAPH ) are developed to measure antioxidant capacity at physiological pH, using indigo carmine as a redox dye. TEAC OH and TEAC AAPH determine foodstuffs' scavenging capacity against hydroxyl (OH) and AAPH radicals, while the third method measures the global reducing capacity of the sample. The results obtained for commercial teas, commercial beverages containing tea as the main ingredient and different solid foods (spinach, onion, salami, etc.) were compared with well-established protocols. The new methods demonstrated good linearity-reproducibility, providing reliable data about the antioxidant capacity of foods under physiological-resembling conditions. The new methods were also useful for evaluating the antioxidant capacity of human plasma after acute intake of tea. The physiological-resembling conditions of these assays and the use of absorbance readings make them suitable for application by any laboratory. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Familial resemblance of borderline personality disorder features: genetic or cultural transmission?

    Directory of Open Access Journals (Sweden)

    Marijn A Distel

    Full Text Available Borderline personality disorder is a severe personality disorder for which genetic research has been limited to family studies and classical twin studies. These studies indicate that genetic effects explain 35 to 45% of the variance in borderline personality disorder and borderline personality features. However, effects of non-additive (dominance genetic factors, non-random mating and cultural transmission have generally not been explored. In the present study an extended twin-family design was applied to self-report data of twins (N = 5,017 and their siblings (N = 1,266, parents (N = 3,064 and spouses (N = 939 from 4,015 families, to estimate the effects of additive and non-additive genetic and environmental factors, cultural transmission and non-random mating on individual differences in borderline personality features. Results showed that resemblance among biological relatives could completely be attributed to genetic effects. Variation in borderline personality features was explained by additive genetic (21%; 95% CI 17-26% and dominant genetic (24%; 95% CI 17-31% factors. Environmental influences (55%; 95% CI 51-60% explained the remaining variance. Significant resemblance between spouses was observed, which was best explained by phenotypic assortative mating, but it had only a small effect on the genetic variance (1% of the total variance. There was no effect of cultural transmission from parents to offspring.

  20. Virtual reality for engineering

    CERN Document Server

    De Gennaro, Silvano; CERN. Geneva

    1996-01-01

    Virtual Reality for Engineers. Virtual Reality is a very powerful visualization technique for 3D data, which can bring enormous benefits to engineering design. CAD models can be exported to a VR application and used as "Virtual Prototypes". Virtual Prototypes are an ideal replacement for wooden models as they can be generated automatically from most CAD products. They are totally reliable, they can be updated in a matter of minutes, and they allow designers to explore them from inside, on a one-to-one scale and using a 3D-stereo vision. Navigation can be performed using a number of instinctive tools, such as joysticks, spaceballs, VR helmets and 3D mice. The lectures will cover today's Virtual Reality products and methods, and describe how to transform CAD models into Virtual Prototypes. A "hands on" VR experience featuring the LHC detectors models can be organized for people interested.

  1. Transforming Virtual Teams

    DEFF Research Database (Denmark)

    Bjørn, Pernille

    2005-01-01

    Investigating virtual team collaboration in industry using grounded theory this paper presents the in-dept analysis of empirical work conducted in a global organization of 100.000 employees where a global virtual team with participants from Sweden, United Kingdom, Canada, and North America were...... studied. The research question investigated is how collaboration is negotiated within virtual teams? This paper presents findings concerning how collaboration is negotiated within a virtual team and elaborate the difficulties due to invisible articulation work and managing multiple communities...... in transforming the virtual team into a community. It is argued that translucence in communication structures within the virtual team and between team and management is essential for engaging in a positive transformation process of trustworthiness supporting the team becoming a community, managing the immanent...

  2. Learning by doing virtually.

    Science.gov (United States)

    von Sternberg, N; Bartsch, M S; Petersik, A; Wiltfang, J; Sibbersen, W; Grindel, T; Tiede, U; Warnke, P H; Heiland, M; Russo, P A J; Terheyden, H; Pohlenz, P; Springer, I N

    2007-05-01

    Selective reduction of bone without collateral damage (nerves, teeth) is essential in apicectomy. To test whether skills acquired on a virtual apicectomy simulator (VOXEL-MAN system with integrated force-feedback) are transferable from virtual to physical reality, two groups of trainees were compared. Group 1 received computer-based virtual surgical training before performing an apicectomy in a pig cadaver model. The probability of preserving vital neighboring structures was improved significantly, i.e. six-fold, after virtual surgical training (P<0.001). The average volume of the bony defects created by the trainees of Group 2 (mean: 0.47 ml) was significantly (P<0.001) larger than by the trainees of Group 1 (mean: 0.25 ml). Most importantly, the ability to objectively self-assess performance was significantly improved after virtual training. Training with a virtual apicectomy simulator appears to be effective, and the skills acquired are transferable to physical reality.

  3. 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

  4. Virtual Campus Hub technology

    DEFF Research Database (Denmark)

    Vercoulen, Frank; Badger, Merete; Monaco, Lucio

    This deliverable briefly describes which technological components have been delivered for the Virtual Campus Hub and how they can be used. A detailed discussion of the technical details of the components, how they were realized and how they fit the VCH concept can be found in deliverables D5.......4. Virtual Campus Hub Technology Evaluation Report and D6.7 The Virtual Campus Hub Concept....

  5. Trust and virtual worlds

    DEFF Research Database (Denmark)

    Ess, Charles; Thorseth, May

    2011-01-01

    by virtuality, such as virtual child pornography. The introduction further develops a philosophical anthropology, rooted in Kantian ethics, phenomenology, virtue ethics, and feminist perspectives, that grounds a specific approach to ethical issues in virtual environments....... of embodiment in establishing trust in (primarily) disembodied venues; how far artificial agents and other forms of machine intelligence can be trusted in any strong sense; and how diverse ethical frameworks, as developed in embodied contexts and histories, may (not) be applied to ethical issues evoked...

  6. Photon virtual bound state

    International Nuclear Information System (INIS)

    Inoue, J.; Ohtaka, K.

    2004-01-01

    We study virtual bound states in photonics, which are a vectorial extension of electron virtual bound states. The condition for these states is derived. It is found that the Mie resonant state which satisfies the condition that the size parameter is less than the angular momentum should be interpreted as a photon virtual bound state. In order to confirm the validity of the concept, we compare the photonic density of states, the width of which represents the lifetime of the photon virtual bound states, with numerical results

  7. High availability using virtualization

    International Nuclear Information System (INIS)

    Calzolari, Federico; Arezzini, Silvia; Ciampa, Alberto; Mazzoni, Enrico; Domenici, Andrea; Vaglini, Gigliola

    2010-01-01

    High availability has always been one of the main problems for a data center. Till now high availability was achieved by host per host redundancy, a highly expensive method in terms of hardware and human costs. A new approach to the problem can be offered by virtualization. Using virtualization, it is possible to achieve a redundancy system for all the services running on a data center. This new approach to high availability allows the running virtual machines to be distributed over a small number of servers, by exploiting the features of the virtualization layer: start, stop and move virtual machines between physical hosts. The 3RC system is based on a finite state machine, providing the possibility to restart each virtual machine over any physical host, or reinstall it from scratch. A complete infrastructure has been developed to install operating system and middleware in a few minutes. To virtualize the main servers of a data center, a new procedure has been developed to migrate physical to virtual hosts. The whole Grid data center SNS-PISA is running at the moment in virtual environment under the high availability system.

  8. Secure Virtual Enclaves

    National Research Council Canada - National Science Library

    Shands, Deborah

    2002-01-01

    The Secure Virtual Enclaves (SVE) collaboration infrastructure allows multiple organizations to share their distributed application resources, while respecting organizational autonomy over local resources...

  9. Virtual Training Devices Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Virtual Training Devices (VTD) Laboratory at the Life Cycle Software Engineering Center, Picatinny Arsenal, provides a software testing and support environment...

  10. Virtual Environments for Training

    National Research Council Canada - National Science Library

    Stiles, R

    1998-01-01

    .... Progress on productization of the VET Training Studio software includes increased robustness for Vista virtual environment display and interaction services, a new capability to use the STEVE visual...

  11. Virtual Reality Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Performs basic and applied research in interactive 3D computer graphics, including visual analytics, virtual environments, and augmented reality (AR). The...

  12. A standardized set of 3-D objects for virtual reality research and applications.

    Science.gov (United States)

    Peeters, David

    2017-06-23

    The use of immersive virtual reality as a research tool is rapidly increasing in numerous scientific disciplines. By combining ecological validity with strict experimental control, immersive virtual reality provides the potential to develop and test scientific theories in rich environments that closely resemble everyday settings. This article introduces the first standardized database of colored three-dimensional (3-D) objects that can be used in virtual reality and augmented reality research and applications. The 147 objects have been normed for name agreement, image agreement, familiarity, visual complexity, and corresponding lexical characteristics of the modal object names. The availability of standardized 3-D objects for virtual reality research is important, because reaching valid theoretical conclusions hinges critically on the use of well-controlled experimental stimuli. Sharing standardized 3-D objects across different virtual reality labs will allow for science to move forward more quickly.

  13. Not all that glitters is gold-Electron microscopy study on uptake of gold nanoparticles in Daphnia magna and related artifacts.

    Science.gov (United States)

    Jensen, Louise Helene Søgaard; Skjolding, Lars Michael; Thit, Amalie; Sørensen, Sara Nørgaard; Købler, Carsten; Mølhave, Kristian; Baun, Anders

    2017-06-01

    Increasing use of engineered nanoparticles has led to extensive research into their potential hazards to the environment and human health. Cellular uptake from the gut is sparsely investigated, and microscopy techniques applied for uptake studies can result in misinterpretations. Various microscopy techniques were used to investigate internalization of 10-nm gold nanoparticles in Daphnia magna gut lumen and gut epithelial cells following 24-h exposure and outline potential artifacts (i.e., high-contrast precipitates from sample preparation related to these techniques). Light sheet microscopy confirmed accumulation of gold nanoparticles in the gut lumen. Scanning transmission electron microscopy and elemental analysis revealed gold nanoparticles attached to the microvilli of gut cells. Interestingly, the peritrophic membrane appeared to act as a semipermeable barrier between the lumen and the gut epithelium, permitting only single particles through. Structures resembling nanoparticles were also observed inside gut cells. Elemental analysis could not verify these to be gold, and they were likely artifacts from the preparation, such as osmium and iron. Importantly, gold nanoparticles were found inside holocrine cells with disrupted membranes. Thus, false-positive observations of nanoparticle internalization may result from either preparation artifacts or mistaking disrupted cells for intact cells. These findings emphasize the importance of cell integrity and combining elemental analysis with the localization of internalized nanoparticles using transmission electron microscopy. Environ Toxicol Chem 2017;36:1503-1509. © 2016 SETAC. © 2016 SETAC.

  14. Anastellin, an FN3 Fragment with Fibronectin Polymerization Activity, Resembles Amyloid Fibril Precursors

    Energy Technology Data Exchange (ETDEWEB)

    Briknarova, Klara (The Burnham Institute); Akermann, Maria (The Burnham Institute); Hoyt, David W.(BATTELLE (PACIFIC NW LAB)); Ruoslahti, Erkki (The Burnham Institute); Ely, Kathryn R.(The Burnham Institute)

    2003-08-01

    Anastellin is a carboxy-terminal fragment of the 1st FN3 domain from human fibronectin. It is capable of polymerizing fibronectin in vitro, and it displays anti-tumor, antimetastatic and anti-angiogenic properties in vivo. We have determined the structure of anastellin using nuclear magnetic resonance spectroscopy and identified residues critical for its activity. Anastellin exhibits dynamic fluctuations and conformational exchange in solution. Its overall topology is very similar to the corresponding region of full-length FN3 domains. However, its hydrophobic core becomes solvent accessible and some of its -strands lose their protection against hydrogen bonding to -strands from other molecules. These features seem to be relevant for the fibronectin polymerization activity of anastellin and resemble the characteristics of amyloid fibril precursors. We suggest that this analogy is not random and may reflect similarities between fibronectin and amyloid fibril formation.

  15. A renal adenocarcinoma in a corn snake (Pantherophis guttatus) resembling human collecting duct carcinoma.

    Science.gov (United States)

    Kao, Chi-Fei; Chen, Jiun-Liang; Tsao, Wen-Tien; Lee, An-Hsing; Liu, Chen-Hsuan; Wang, Fun-In

    2016-09-01

    A 5-year-old male captive corn snake (Pantherophis guttatus) with caudal coelomic swelling was admitted for surgical treatment. Laparotomy revealed a 5 × 4 × 2.5 cm, firm, expansile, irregularly shaped mass arising from the middle portion of the right kidney with a mild lobulated pattern and mottled white-to-tan. Microscopically, the mass was composed of numerous bizarre angulated tubules of polygonal neoplastic cells separated by a scirrhous stroma with remarkable heterophilic infiltrates. The neoplastic cells were nonciliated and mucin secreting, with abundant brightly eosinophilic cytoplasm. There were marked cellular and nuclear atypia, frequent cell individualization, and stromal invasion, indicative of malignant behavior, which was confirmed by metastasis to the left kidney 1.5 months postoperatively. Both neoplastic epithelial cells and mesenchymal cells contributing to the scirrhous stroma had variable immunopositivity for pan-cytokeratin. The neoplasm was considered a renal adenocarcinoma resembling human collecting duct carcinoma. © 2016 The Author(s).

  16. Westermarck, Freud, and the incest taboo: does familial resemblance activate sexual attraction?

    Science.gov (United States)

    Fraley, R Chris; Marks, Michael J

    2010-09-01

    Evolutionary psychological theories assume that sexual aversions toward kin are triggered by a nonconscious mechanism that estimates the genetic relatedness between self and other. This article presents an alternative perspective that assumes that incest avoidance arises from consciously acknowledged taboos and that when awareness of the relationship between self and other is bypassed, people find individuals who resemble their kin more sexually appealing. Three experiments demonstrate that people find others more sexually attractive if they have just been subliminally exposed to an image of their opposite-sex parent (Experiment 1) or if the face being rated is a composite image based on the self (Experiment 2). This finding is reversed when people are aware of the implied genetic relationship (Experiment 3). These findings have implications for a century-old debate between E. Westermarck and S. Freud, as well as contemporary research on evolution, mate choice, and sexual imprinting.

  17. A case of Scabies with Lesions Resembling Perforating Folliculitis and Uremic Pruritus

    Directory of Open Access Journals (Sweden)

    Hülya Akgün

    2010-10-01

    Full Text Available Scabies is an infestation caused by Sarcoptes scabiei and characterised by polymorphous lesions that may include burrows, papules, pustules, crusts and excoriations. Several pruritic diseases may be confused with scabies. Herein, we present a case of scabies with lesions resembling perforating folliculitis diagnosed on the basis of both clinical and histopathological view. A 72-year-old man with type 2 diabetes mellitus and receiving hemodialysis for ten years due to end-stage renal disease was admitted to our dermatology department with a 6-month history of severe pruritus. Based on the results of skin biopsy revealing Sarcoptes scabiei in the epidermis, the patient was diagnosed as scabies and was successfully treated with 5% permethrin. This case is presented to emphasize that scabies should be considered in the differential diagnosis in cases of chronic pruritus.

  18. Menstrual blood closely resembles the uterine immune micro-environment and is clearly distinct from peripheral blood

    NARCIS (Netherlands)

    Molen, R.G. van der; Schutten, J.H.; Cranenbroek, B. van; Meer, M. ter; Donckers, J.; Scholten, R.R.; Heijden, O.W.H. van der; Spaanderman, M.E.A.; Joosten, I.

    2014-01-01

    STUDY QUESTION: Is menstrual blood a suitable source of endometrial derived lymphocytes? SUMMARY ANSWER: Mononuclear cells isolated from menstrual samples (menstrual blood mononuclear cells (MMC)) are clearly distinct from peripheral blood mononuclear cells (PBMC) and show a strong resemblance with

  19. 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)

  20. 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.

  1. The virtual GULLIVER project

    NARCIS (Netherlands)

    Trappl, R.; Nijholt, Antinus; Stuk, M.; Zwiers, Jakob

    2002-01-01

    In this paper we discuss our virtual reality project Gulliver. This project is part of a more comprehensive project conceived by two artists, Matjaž Štuk and Alena Hudcovicová, called “Gulliver’s Museum of Living Art��?. Our part of the project involves a virtual reality version of Swift’s Gulliver

  2. 10 Myths of Virtualization

    Science.gov (United States)

    Schaffhauser, Dian

    2012-01-01

    Half of servers in higher ed are virtualized. But that number's not high enough for Link Alander, interim vice chancellor and CIO at the Lone Star College System (Texas). He aspires to see 100 percent of the system's infrastructure requirements delivered as IT services from its own virtualized data centers or other cloud-based operators. Back in…

  3. A Virtual Good Idea

    Science.gov (United States)

    Bolch, Matt

    2009-01-01

    School districts across the country have always had to do more with less. Funding goes only so far, leaving administrators and IT staff to find innovative ways to save money while maintaining a high level of academic quality. Creating virtual servers accomplishes both tasks, district technology personnel say. Virtual environments not only allow…

  4. Virtual Seminar Room

    DEFF Research Database (Denmark)

    Forchhammer, Søren Otto; Fosgerau, Anders; Hansen, Peter Søren Kirk

    1999-01-01

    The initial design considerations and research goals for an ATM network based virtual seminar room with 5 sites are presented.......The initial design considerations and research goals for an ATM network based virtual seminar room with 5 sites are presented....

  5. OVERLAPPING VIRTUAL CADASTRAL DOCUMENTATION

    Directory of Open Access Journals (Sweden)

    Madalina - Cristina Marian

    2013-12-01

    Full Text Available Two cadastrale plans of buildings, can overlap virtual. Overlap is highlighted when digital reception. According to Law no. 7/1996 as amended and supplemented, to solve these problems is by updating the database graphs, the repositioning. This paper addresses the issue of overlapping virtual cadastre in the history of the period 1999-2012.

  6. Virtual Peace Education

    Science.gov (United States)

    Firer, Ruth

    2008-01-01

    This article is based on the convictions that peace education is the basis for any sustainable non-violent relations between parties in a conflict, and that virtual peace education is almost the only feasible way to practise peace education in an open violent conflict as is the current Israeli/Palestinians one. Moreover, virtual peace education…

  7. Designing Virtual Learning Environments

    DEFF Research Database (Denmark)

    Veirum, Niels Einar

    2003-01-01

    The main objective of this working paper is to present a conceptual model for media integrated communication in virtual learning environments. The model for media integrated communication is very simple and identifies the necessary building blocks for virtual place making in a synthesis of methods...

  8. Digging the Virtual Past

    Science.gov (United States)

    Polymeropoulou, Panagiota

    2014-01-01

    In this paper we will investigate the way that the technological progress and the Informatics contributed greatly to the field of Archaeology. There will be analyzed the terms of virtual archaeology and virtual reality in archaeology and there will be an extended reference to the applications and the computer graphics that archaeologists could use…

  9. Virtual Company and Modelbank

    DEFF Research Database (Denmark)

    Thorsteinsson, Uffe

    1996-01-01

    Ansøgning til Socrates programmet vedr. Tematisk netværk inden for området Virtual Company and Modelbank......Ansøgning til Socrates programmet vedr. Tematisk netværk inden for området Virtual Company and Modelbank...

  10. Taxation of virtual currency

    NARCIS (Netherlands)

    Bal, Aleksandra Marta

    2014-01-01

    The Information Age has created a new concept of money – virtual currencies existing solely in the cyberspace in the form of intangible computer code. The most prominent virtual currency scheme, Bitcoin, grabbed the public attention as its value skyrocketed at the beginning of 2012. Whereas Bitcoin

  11. VEM: Virtual Enterprise Methodology

    DEFF Research Database (Denmark)

    Tølle, Martin; Vesterager, Johan

    2003-01-01

    This chapter presents a virtual enterprise methodology (VEM) that outlines activities to consider when setting up and managing virtual enterprises (VEs). As a methodology the VEM helps companies to ask the right questions when preparing for and setting up an enterprise network, which works as a b...

  12. Representing Large Virtual Worlds

    NARCIS (Netherlands)

    Kol, T.R.

    2018-01-01

    The ubiquity of large virtual worlds and their growing complexity in computer graphics require efficient representations. This means that we need smart solutions for the underlying storage of these complex environments, but also for their visualization. How the virtual world is best stored and how

  13. The Erasmus Virtual Campus

    Science.gov (United States)

    Isakeit, D.

    2002-02-01

    The Erasmus Virtual Campus was inaugurated in September 2000 to bring together scientists and engineers interested in using the International Space Station and other facilities for their research. It also provides the foundation for creating Virtual Institutes in selected scientific disciplines. The current capabilities of the Campus are highlighted, along with plans for the future.

  14. Virtual Pediatric Hospital

    Science.gov (United States)

    ... Imaging Encyclopedia of Pediatric Thoracic Disease Virtual Pediatric Hospital is the Apprentice's Assistant™ Last revised on February ... GeneralPediatrics.com | PediatricEducation.org | SearchingPediatrics.com Virtual Pediatric Hospital is curated by Donna M. D'Alessandro, M. ...

  15. The Virtual Dressing Room

    DEFF Research Database (Denmark)

    Holte, Michael Boelstoft; Gao, Yi; Petersson, Eva

    2015-01-01

    This paper presents the design and evaluation of a usability and user experience test of a virtual dressing room. First, we motivate and introduce our recent developed prototype of a virtual dressing room. Next, we present the research and test design grounded in related usability and user experi...

  16. The issue of virtual teams

    OpenAIRE

    Fleiberková, Šárka

    2012-01-01

    The aim of this diploma thesis is the introduction of teamwork and virtual teams. The theoretical part of this work describes the birth of teamwork, its definition, properties, advantages and disadvantages. Next part of diploma thesis is dedicated to the virtual team. It describes the difference among virtual and traditional team, definition and characteristics of virtual team as well as tools that are used in virtual team. The second, practical, unit is focused on virtual teams at universiti...

  17. Organization Virtual or Networked?

    Directory of Open Access Journals (Sweden)

    Rūta Tamošiūnaitė

    2013-08-01

    Full Text Available Purpose—to present distinction between “virtual organization” and “networked organization”; giving their definitions.Design/methodology/approach—review of previous researches, systemic analyses of their findings and synthesis of distinctive characteristics of ”virtual organization” and “networked organization.”Findings—the main result of the research is key diverse features separating ”virtual organization” and ”networked organization.” Definitions of “virtual organization” and “networked organization” are presented.Originality/Value—distinction between “virtual organization” and “networked organization” creates possibilities to use all advantages of those types of organizations and gives foundation for deeper researches in this field.Research type: general review.

  18. 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...

  19. 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.

  20. 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...

  1. The predecessors of bitcoin and their implications for the prospect of virtual currencies.

    Directory of Open Access Journals (Sweden)

    Thomas Kim

    Full Text Available To examine whether the recent price patterns and transaction costs of Bitcoin represent a general characteristic of decentralized virtual currencies, we analyze virtual currencies in online games that have been voluntarily managed by individuals since 1990s. We find that matured game currencies have price stability similar to that of small size equities or gold, and their transaction costs are sometimes lower than real currencies. Assuming that virtual currencies with a longer history can provide an estimate for Bitcoin's prospects, we project that Bitcoin will be less influenced by speculative trades and become a low cost alternative to real currencies.

  2. The predecessors of bitcoin and their implications for the prospect of virtual currencies.

    Science.gov (United States)

    Kim, Thomas

    2014-01-01

    To examine whether the recent price patterns and transaction costs of Bitcoin represent a general characteristic of decentralized virtual currencies, we analyze virtual currencies in online games that have been voluntarily managed by individuals since 1990s. We find that matured game currencies have price stability similar to that of small size equities or gold, and their transaction costs are sometimes lower than real currencies. Assuming that virtual currencies with a longer history can provide an estimate for Bitcoin's prospects, we project that Bitcoin will be less influenced by speculative trades and become a low cost alternative to real currencies.

  3. The Predecessors of Bitcoin and Their Implications for the Prospect of Virtual Currencies

    Science.gov (United States)

    Kim, Thomas

    2015-01-01

    To examine whether the recent price patterns and transaction costs of Bitcoin represent a general characteristic of decentralized virtual currencies, we analyze virtual currencies in online games that have been voluntarily managed by individuals since 1990s. We find that matured game currencies have price stability similar to that of small size equities or gold, and their transaction costs are sometimes lower than real currencies. Assuming that virtual currencies with a longer history can provide an estimate for Bitcoin’s prospects, we project that Bitcoin will be less influenced by speculative trades and become a low cost alternative to real currencies. PMID:25919027

  4. 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...

  5. Virtual microscopy in virtual tumor banking

    NARCIS (Netherlands)

    Isabelle, M.; Teodorovic, I.; Oosterhuis, J. W.; Riegman, P. H. J.; Passioukov, A.; Lejeune, S.; Therasse, P.; Dinjens, W. N. M.; Lam, K. H.; Oomen, M. H. A.; Spatz, A.; Ratcliffe, C.; Knox, K.; Mager, R.; Kerr, D.; Pezzella, F.; van Damme, B.; van de Vijver, M.; van Boven, H.; Morente, M. M.; Alonso, S.; Kerjaschki, D.; Pammer, J.; López-Guerrero, J. A.; Llombart-Bosch, A.; Carbone, A.; Gloghini, A.; van Veen, E. B.

    2006-01-01

    Many systems have already been designed and successfully used for sharing histology images over large distances, without transfer of the original glass slides. Rapid evolution was seen when digital images could be transferred over the Internet. Nowadays, sophisticated virtual microscope systems can

  6. Land Use Change Driven by Gold Mining; Peruvian Amazon

    Science.gov (United States)

    Swenson, J. J.; Carter, C. E.; domec, J.; Delgado, C. I.

    2011-12-01

    Many factors such as poverty, ineffective institutions and environmental regulations may prevent developing countries from managing how natural resources are extracted to meet a strong market demand. Extraction for some resources has reached such proportions that evidence is measurable from space. We present recent evidence of the global demand for a single commodity and the ecosystem destruction resulting from commodity extraction, recorded by satellites for one of the most biodiverse areas of the world. We find that since 2003, recent mining deforestation in Madre de Dios, Peru is increasing nonlinearly alongside a constant annual rate of increase in international gold price (~18%/yr). We detect that the new pattern of mining deforestation (1915 ha/year, 2006-2009) is outpacing that of nearby settlement deforestation. We show that gold price is linked with exponential increases in Peruvian national mercury imports over time (R2 = 0.93, p = 0.04, 2003- 2009). Given the past rates of increase we predict that mercury imports may more than double for 2011 (~500 t/year). Virtually all of Peru's mercury imports are used in artisanal gold mining. Much of the mining increase is unregulated/ artisanal in nature, lacking environmental impact analysis or miner education. As a result, large quantities of mercury are being released into the atmosphere, sediments and waterways. Other developing countries endowed with gold deposits are likely experiencing similar environmental destruction in response to recent record high gold prices. The increasing availability of satellite imagery ought to evoke further studies linking economic variables with land use and cover changes on the ground.

  7. 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 ...

  8. Virtual Machine Logbook - Enabling virtualization for ATLAS

    International Nuclear Information System (INIS)

    Yao Yushu; Calafiura, Paolo; Leggett, Charles; Poffet, Julien; Cavalli, Andrea; Frederic, Bapst

    2010-01-01

    ATLAS software has been developed mostly on CERN linux cluster lxplus or on similar facilities at the experiment Tier 1 centers. The fast rise of virtualization technology has the potential to change this model, turning every laptop or desktop into an ATLAS analysis platform. In the context of the CernVM project we are developing a suite of tools and CernVM plug-in extensions to promote the use of virtualization for ATLAS analysis and software development. The Virtual Machine Logbook (VML), in particular, is an application to organize work of physicists on multiple projects, logging their progress, and speeding up ''context switches'' from one project to another. An important feature of VML is the ability to share with a single 'click' the status of a given project with other colleagues. VML builds upon the save and restore capabilities of mainstream virtualization software like VMware, and provides a technology-independent client interface to them. A lot of emphasis in the design and implementation has gone into optimizing the save and restore process to makepractical to store many VML entries on a typical laptop disk or to share a VML entry over the network. At the same time, taking advantage of CernVM's plugin capabilities, we are extending the CernVM platform to help increase the usability of ATLAS software. For example, we added the ability to start the ATLAS event display on any computer running CernVM simply by clicking a button in a web browser. We want to integrate seamlessly VML with CernVM unique file system design to distribute efficiently ATLAS software on every physicist computer. The CernVM File System (CVMFS) download files on-demand via HTTP, and cache it locally for future use. This reduces by one order of magnitude the download sizes, making practical for a developer to work with multiple software releases on a virtual machine.

  9. Virtual reality exposure therapy for anxiety disorders: the state of the art

    NARCIS (Netherlands)

    Meyerbröker, K.; Emmelkamp, P.M.G.; Brahnam, S.; Jain, L.C.

    2011-01-01

    In the past 10 years virtual reality exposure therapy (VRET) has become a viable alternative for exposure in vivo, the gold standard for the treatment of anxiety disorders. VRET is often regarded as a natural extension of the systematic exposure component of (cognitive) behavior therapy. The

  10. 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...

  11. 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.

  12. 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.

  13. 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...

  14. Effect of facial self-resemblance on the startle response and subjective ratings of erotic stimuli in heterosexual men.

    Science.gov (United States)

    Lass-Hennemann, Johanna; Deuter, Christian E; Kuehl, Linn K; Schulz, Andre; Blumenthal, Terry D; Schachinger, Hartmut

    2011-10-01

    Cues of kinship are predicted to increase prosocial behavior due to the benefits of inclusive fitness, but to decrease approach motivation due to the potential costs of inbreeding. Previous studies have shown that facial resemblance, a putative cue of kinship, increases prosocial behavior. However, the effects of facial resemblance on mating preferences are equivocal, with some studies finding that facial resemblance decreases sexual attractiveness ratings, while other studies show that individuals choose mates partly on the basis of similarity. To further investigate this issue, a psychophysiological measure of affective processing, the startle response, was used in this study, assuming that differences in approach motivation to erotic pictures will modulate startle. Male volunteers (n = 30) viewed 30 pictures of erotic female nudes while startle eyeblink responses were elicited by acoustic noise probes. The female nude pictures were digitally altered so that the face either resembled the male participant or another participant, or were not altered. Non-nude neutral pictures were also included. Importantly, the digital alteration was undetected by the participants. Erotic pictures were rated as being pleasant and clearly reduced startle eyeblink magnitude as compared to neutral pictures. Participants showed greater startle inhibition to self-resembling than to other-resembling or non-manipulated female nude pictures, but subjective pleasure and arousal ratings did not differ among the three erotic picture categories. Our data suggest that visual facial resemblance of opposite-sex nudes increases approach motivation in men, and that this effect was not due to their conscious evaluation of the erotic stimuli.

  15. 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...

  16. Virtualization Security Combining Mandatory Access Control and Virtual Machine Introspection

    OpenAIRE

    Win, Thu Yein; Tianfield, Huaglory; Mair, Quentin

    2014-01-01

    Virtualization has become a target for attacks in cloud computing environments. Existing approaches to protecting the virtualization environment against the attacks are limited in protection scope and are with high overheads. This paper proposes a novel virtualization security solution which aims to provide comprehensive protection of the virtualization environment.

  17. Virtual Law -- Will real and virtual identity converge or diverge?

    OpenAIRE

    Dave Birch

    2003-01-01

    Some of the differences (conflicts, even) between real and virtual identity are thrown into sharp relief in the world of online games, where vast virtual worlds are already inhabited by millions of virtual characters. While they might be ÒonlyÓ games, they may contain some real insights into the future relationship between real and virtual identities.

  18. 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)

  19. Virtual neutron scattering experiments

    DEFF Research Database (Denmark)

    Overgaard, Julie Hougaard; Bruun, Jesper; May, Michael

    2016-01-01

    We describe how virtual experiments can be utilized in a learning design that prepares students for hands-on experiments at large-scale facilities. We illustrate the design by showing how virtual experiments are used at the Niels Bohr Institute in a master level course on neutron scattering....... In the last week of the course, students travel to a large-scale neutron scattering facility to perform real neutron scattering experiments. Through student interviews and survey answers, we argue, that the virtual training prepares the students to engage more fruitfully with experiments by letting them focus...

  20. Virtual neutron scattering experiments

    DEFF Research Database (Denmark)

    Overgaard, Julie Hougaard; Bruun, Jesper; May, Michael

    2017-01-01

    We describe how virtual experiments can be utilized in a learning design that prepares students for hands-on experiments at large-scale facilities. We illustrate the design by showing how virtual experiments are used at the Niels Bohr Institute in a master level course on neutron scattering....... In the last week of the course, students travel to a large-scale neutron scattering facility to perform real neutron scattering experiments. Through student interviews and survey answers, we argue, that the virtual training prepares the students to engage more fruitfully with experiments by letting them focus...

  1. Virtual Balancing for Studying and Training Postural Control

    Directory of Open Access Journals (Sweden)

    Daniela Buettner

    2017-09-01

    Full Text Available Postural control during free stance has been frequently interpreted in terms of balancing an inverted pendulum. This even holds, if subjects do not balance their own, but an external body weight. We introduce here a virtual balancing apparatus, which produces torque in the ankle joint as a function of ankle angle resembling the gravity and inertial effects of free standing. As a first aim of this study, we systematically modified gravity, damping, and inertia to examine its effect on postural control beyond the physical constraints given in the real world. As a second aim, we compared virtual balancing to free stance to test its suitability for balance training in patients who are not able to balance their full body weight due to certain medical conditions. In a feasibility study, we analyzed postural control during free stance and virtual balancing in 15 healthy subjects. Postural control was characterized by spontaneous sway measures and measures of perturbed stance. During free stance, perturbations were induced by pseudorandom anterior-posterior tilts of the body support surface. In the virtual balancing task, we systematically varied the anterior-posterior position of the foot plate where the balancing forces are zero following a similar pseudorandom stimulus profile. We found that subjects' behavior during virtual balancing resembles free stance on a tilting platform. This specifically holds for the profile of body excursions as a function of stimulus frequencies. Moreover, non-linearity between stimulus and response amplitude is similar in free and virtual balancing. The overall larger stimulus induced body excursions together with an altered phase behavior between stimulus and response could be in part explained by the limited use of vestibular and visual feedback in our experimental setting. Varying gravity or damping significantly affected postural behavior. Inertia as an isolated factor had a mild effect on the response functions. We

  2. Prion disease resembling frontotemporal dementia and parkinsonism linked to chromosome 17

    Directory of Open Access Journals (Sweden)

    Nitrini Ricardo

    2001-01-01

    Full Text Available OBJECTIVE: To compare the clinical features of a familial prion disease with those of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17. BACKGROUND: Prion diseases are not usually considered in the differential diagnosis of FTDP-17, since familial Creutzfeldt-Jakob disease (CJD, the most common inherited prion disease, often manifests as a rapidly progressive dementia. Conversely, FTDP-17 usually has an insidious onset in the fifth decade, with abnormal behavior and parkinsonian features. METHOD: We present the clinical features of 12 patients from a family with CJD associated with a point mutation at codon 183 of the prion protein gene. RESULTS: The mean age at onset was 44.0 ± 3.7; the duration of the symptoms until death ranged from two to nine years. Behavioral disturbances were the predominant presenting symptoms. Nine patients were first seen by psychiatrists. Eight patients manifested parkinsonian signs. CONCLUSION: These clinical features bear a considerable resemblance to those described in FTDP-17.

  3. On Learning Natural-Science Categories That Violate the Family-Resemblance Principle.

    Science.gov (United States)

    Nosofsky, Robert M; Sanders, Craig A; Gerdom, Alex; Douglas, Bruce J; McDaniel, Mark A

    2017-01-01

    The general view in psychological science is that natural categories obey a coherent, family-resemblance principle. In this investigation, we documented an example of an important exception to this principle: Results of a multidimensional-scaling study of igneous, metamorphic, and sedimentary rocks (Experiment 1) suggested that the structure of these categories is disorganized and dispersed. This finding motivated us to explore what might be the optimal procedures for teaching dispersed categories, a goal that is likely critical to science education in general. Subjects in Experiment 2 learned to classify pictures of rocks into compact or dispersed high-level categories. One group learned the categories through focused high-level training, whereas a second group was required to simultaneously learn classifications at a subtype level. Although high-level training led to enhanced performance when the categories were compact, subtype training was better when the categories were dispersed. We provide an interpretation of the results in terms of an exemplar-memory model of category learning.

  4. Pulmonary Extramedullary Hematopoiesis in a Patient with Chronic Asthma Resembling Lung Cancer: A Case Report

    Directory of Open Access Journals (Sweden)

    Massood Hosseinzadeh

    2012-01-01

    Full Text Available Background. Extramedullary hematopoiesis is most often seen in reticuloendothelial organs specially spleen, liver, or lymph nodes, and it is rarely seen in lung parenchyma. Almost all reported cases of pulmonary extramedullary hematopoiesis occurred following myeloproliferative disorders specially myelofibrosis. Other less common underlying causes are thalassemia syndromes and other hemoglobinopathies. There was not any reported case of pulmonary extramedullary hematopoiesis in asthmatic patients in the medical literature. Case. Here we reported a 65-year-old lady who was a known case of bronchial asthma with recent developed right lower lobe lung mass. Chest X-ray and CT studies showed an infiltrating mass resembling malignancy. Fine needle aspiration cytology of mass revealed pulmonary extramedullary hematopoiesis. The patient followed for 10 months with serial physical examination and laboratory evaluations which were unremarkable. Conclusion. Extramedullary hematopoiesis of lung parenchyma can be mistaken for lung cancer radiologically. Although previous reported cases occurred with myelofibrosis or hemoglobinopathies, we are reporting the first case of asthma-associated extramedullary hematopoiesis.

  5. Nuclear security culture in comparison with nuclear safety culture. Resemblances and differences

    International Nuclear Information System (INIS)

    Kawata, Norio

    2015-01-01

    Since the terrorist attacks on the U.S. on September 11th, 2001, Nuclear Security has been focused on and treated as a global issue in the international community and it has also been discussed as a real and serious threat to nuclear power plants in the world since 'The Great East Japan Earthquake' in March, 2011. The International Atomic Energy Agency (IAEA) issued a document including Nuclear Security Recommendations (INFCIRC/225/Rev.5) (NSS 13) in the Nuclear Security Series and emphasized the necessity of fostering Nuclear Security Culture. Nuclear Security Culture has been frequently discussed at various kinds of seminars and events. Since the officials in charge of Nuclear Security are familiar with the area of Nuclear Safety, the relationships between Nuclear Safety Culture and Nuclear Security Culture have been the point in controversy. This paper clarifies relevance between Nuclear Safety and Security, considers resemblances and differences of their concepts and lessons learned for each culture from nuclear power plant accidents, and promotes deeper understanding of Nuclear Safety and Nuclear Security Culture. (author)

  6. Granular cell ameloblastoma: case report of a particular ameloblastoma histologically resembling oncocytoma.

    Science.gov (United States)

    Matsushita, Yuki; Fujita, Shuichi; Kawasaki, Goro; Hirota, Yoshinosuke; Rokutanda, Satoshi; Yamashita, Kentaro; Yanamoto, Souichi; Ikeda, Tohru; Umeda, Masahiro

    2015-01-01

    Granular cell ameloblastoma is classified as a histological subtype of solid/multicystic ameloblastoma. Usual granular cell ameloblastoma is histologically characterized by granular changes of stellate-like cells located in the inner portion of the epithelial follicles. Here we report a case of another type of granular cell ameloblastoma, showing predominant anastomosing double-stranded trabeculae of granular cells. This type of granular cell ameloblastoma is extremely rare, and the World Health Organization classification does not contain the entity. We tentatively termed it 'anastomosing granular cell ameloblastoma' in this report. The present case suggests the importance of differential diagnosis because the histology of 'anastomosing granular cell ameloblastoma' resembles that of salivary gland oncocytoma rather than that of usual granular cell ameloblastoma. The trabeculae observed in our case continued to the peripheral cells of a small amount of epithelial sheets of plexiform ameloblastoma, and the tumor cells were positive for CK19, which is regarded as an immunohistochemical marker of odontogenic epithelium. Similar to usual granular cell ameloblastoma, the tumor cells had CD68-positive granules. For precise diagnosis of this condition, immunohistochemistry using CK19 and CD68, as well as detailed histological observation, are recommended. © 2014 Japanese Society of Pathology and Wiley Publishing Asia Pty Ltd.

  7. Manganese Oxides Resembling Microbial Fabrics and Their Implications for Recognizing Inorganically Preserved Microfossils.

    Science.gov (United States)

    Muscente, A D; Czaja, Andrew D; Tuggle, James; Winkler, Christopher; Xiao, Shuhai

    2018-03-01

    In the search for microfossils of early life on Earth, the demonstration of biogenicity is paramount. Traditionally, only syngenetic structures with cellular elaboration, hollow sheaths/cell walls, and indigenous kerogen have been considered bona fide fossils. Recent reports of inorganically preserved microfossils represent a shift from this practice. Such a shift, if accompanied by a robust set of biogenicity criteria, could have profound implications for the identification of biosignatures on early Earth and extraterrestrial bodies. Here, we reaffirm the conventional criteria by examining aggregates of inorganic filaments from the Pilbara region of Western Australia. These aggregates are preserved in bedded chert, and the filaments measure up to 1 μm in diameter and 100 μm in length. The aggregates superficially resemble kerogenous microbial fabrics and mycelial organisms. However, the filaments consist of manganese oxide, lack cellular elaboration, and show no evidence for hollow sheaths or cell walls. We conclude that the filaments are fibrous minerals of abiotic origin. The similarities between these pseudofossils and some filamentous fossils highlight the need for strict application of the conventional criteria for recognizing microfossils. In the absence of kerogen, morphologically simple structures should, at least, show evidence of cellular features to be considered bona fide fossils. Key Words: Fossil-Manganese oxide-Pilbara-Precambrian-Pseudofossil. Astrobiology 18, 249-258.

  8. Ad-hoc KEEN-type Waves and their Occasional Resemblance to KdV Waveforms

    Science.gov (United States)

    Tyshetskiy, Yuriy; Afeyan, Bedros

    2005-10-01

    Nonlinear kinetic waves of the KEEN type [1] but constructed with two BGK recipes are tested with 1D Vlasov-Poisson simulation (1DVPS). One is that of Allis [2] as modified by Johnston (unpublished), the other is that of Eliasson and Shukla [3]. Strong kinetic waves survive well, but not weaker ones. The potential wave trains resemble those from the Korteweg-deVries equation. This proves to be natural when charge density variation with electrostatic potential is like a quadratic polynomial. For expositions on the physics of ponderomotively driven KEEN waves, consult presentations by Afeyan and Savchenko, this conference. (Part of this work was performed under the auspices of the U.S. Department of Energy under grant number DE-FG03-NA00059.) [1] B. Afeyan et al., ``Kinetic Electrostatic Electron Nonlinear (KEEN) Waves and their interactions driven by the ponderomotive force of crossing laser beams'', Proc. IFSA (Inertial Fusion Sciences and Applications 2003, Monterey, CA), 213, B. Hammel, D. Meyerhofer, J. Meyer-ter-Vehn and H. Azechi, editors, American Nuclear Society, 2004. [2] W.P. Allis, paper 3 (pp.21-42), in ``In Honor of Philip M. Morse'', ed. H. Feshbach and K. Ingard, MIT Press (1969). [3] B. Eliasson and P.K. Shukla, Phys. Rev. E 71, 046402 (2005)

  9. An unusual clinical presentation resembling superior vena cava syndrome post heart surgery

    Directory of Open Access Journals (Sweden)

    Pellegrini Ronald

    2005-10-01

    Full Text Available Abstract Background An unusual sequence of post operative events heralded by hemodynamic deterioration followed by dyspnea and rapidly progressive dilatation of superficial neck and facial veins, resembling a superior vena cava syndrome, two days post surgical resection of filamentous aortic valve masses, closure of a patent foramen ovale, and performance of a modified Maze procedure for atrial fibrillation in a patient that presented with transient neurologic findings is presented. Case Presentation Although both clinical findings and hemodynamic derangements completely resolved following tricuspid valve repair aimed to correct the new onset severe tricuspid regurgitation noted post operatively; a clear mechanism was not readily obvious and diagnostic testing data somewhat conflictive. We present a careful retrospective examination of all clinical data and review possible clinical entities that could have been implicated in this particular case and recognize that transesophageal echocardiographic findings were most useful in identifying the best course of action. Conclusion After reviewing all clinical data and despite the inconclusive nature of test results; the retrospective examination of transesophageal echocardiographic findings proved to be most useful in identifying the best course of action. We postulate that in our case, resolution of the suspected pulmonary embolism with anticoagulation and reestablishment of a normal right ventricular geometry with tricuspid valve repair worked in unison in restoring normal hemodynamics and resolving both dyspnea and venous dilatation.

  10. Phenotype-genotype discordance in congenital malformations with communication disorders resembling trisomy 18 (Edwards syndrome)

    Science.gov (United States)

    Pruszewicz, Antoni; Wiskirska-Woźnica, Bożena; Wojnowski, Waldemar; Czerniejewska, Hanna; Jackowska, Joanna; Jarmuż, Małgorzata; Szyfter, Krzysztof; Leszczyńska, Małgorzata

    2014-01-01

    Patient: Female, 6 Final Diagnosis: Phenotype-genotype discordance in congenital malformations with communication disorders resembling trisomy 18 (Edwards syndrome) Symptoms: — Medication: — Clinical Procedure: — Specialty: Otolaryngology Objective: Congenital defects Background: Communication process disorders are very frequent in rare cases of chromosomal aberrations (deletions, insertions, and trisomies) such as Down syndrome (trisomy 21), Turner syndrome, Edwards syndrome (trisomy 18), or Patau syndrome (trisomy 13). Sometimes phenotype may delusively correspond to the characteristic features of a given syndrome, but genotype tests do not confirm its presence. Case Report: We present the case of a 6-year-old girl admitted to the Clinic of Phoniatrics and Audiology for the assessment of communication in the course of congenital malformations with phenotype characteristic for trisomy 18 (Edwards syndrome). Immediately upon birth, dysmorphic changes suggesting trisomy 18 (Edwards syndrome) were observed, but trisomy 18 was excluded after karyotype test results were normal (46, XX). Conclusions: Disturbed articulation was diagnosed: deformed linguo-dental and palatal sounds, interdental realization with flat tongue of the /s/, /z/, /c/, /dz/, /ś/, /ź/, /ć/, /dz/ sounds (sigmatismus interdentalis). Hearing loss was confirmed. PMID:24478819

  11. Phenotype-genotype discordance in congenital malformations with communication disorders resembling trisomy 18 (Edwards syndrome).

    Science.gov (United States)

    Pruszewicz, Antoni; Wiskirska-Woźnica, Bożena; Wojnowski, Waldemar; Czerniejewska, Hanna; Jackowska, Joanna; Jarmuż, Małgorzata; Szyfter, Krzysztof; Leszczyńska, Małgorzata

    2014-01-01

    Female, 6 FINAL DIAGNOSIS: Phenotype-genotype discordance in congenital malformations with communication disorders resembling trisomy 18 (Edwards syndrome) Symptoms: - - Clinical Procedure: - Specialty: Otolaryngology. Congenital defects. Communication process disorders are very frequent in rare cases of chromosomal aberrations (deletions, insertions, and trisomies) such as Down syndrome (trisomy 21), Turner syndrome, Edwards syndrome (trisomy 18), or Patau syndrome (trisomy 13). Sometimes phenotype may delusively correspond to the characteristic features of a given syndrome, but genotype tests do not confirm its presence. We present the case of a 6-year-old girl admitted to the Clinic of Phoniatrics and Audiology for the assessment of communication in the course of congenital malformations with phenotype characteristic for trisomy 18 (Edwards syndrome). Immediately upon birth, dysmorphic changes suggesting trisomy 18 (Edwards syndrome) were observed, but trisomy 18 was excluded after karyotype test results were normal (46, XX). DISTURBED ARTICULATION WAS DIAGNOSED: deformed linguo-dental and palatal sounds, interdental realization with flat tongue of the /s/, /z/, /c/, /dz/, /ś/, /ź/, /ć/, /dz/ sounds (sigmatismus interdentalis). Hearing loss was confirmed.

  12. Virtual Museums as Educational Tool

    DEFF Research Database (Denmark)

    2007-01-01

    Virtual Museums as Educational Tool On this web site you will find a collection of resources on virtual museums. The web site is meant to be a knowledge base for people with interest in museums, virtuality and education, and how virtual museums may contribute to adult education and lifelong...

  13. Virtual Organizations: An Overview

    Science.gov (United States)

    Nami, Mohammad Reza

    The need to remain competitive in the open market forces companies to concentrate on their core competencies while searching for alliances when additional skills or resources are needed to fulfill business opportunities. The changing business situation of companies and customer needs have motivated researchers to introduce Virtual Organization (VO) idea. A Virtual Organization is always a form of partnership and managing partners and handling partnerships are crucial. Virtual organizations are defined as a temporary collection of enterprises that cooperate and share resources, knowledge, and competencies to better respond to business opportunities. This paper presents base concepts of virtual organizations including properties, management concepts, operational concepts, and main issues in collaboration such as security and authentication.

  14. Virtual Factory Testbed

    Data.gov (United States)

    Federal Laboratory Consortium — The Virtual Factory Testbed (VFT) is comprised of three physical facilities linked by a standalone network (VFNet). The three facilities are the Smart and Wireless...

  15. Layered Augmented Virtuality

    National Research Council Canada - National Science Library

    Ahuja, G; Pacis, E. B; Sights, B; Fellars, D; Everett, H. R

    2007-01-01

    ... a virtual-world representation with information from onboard sensors and human input. Standard techniques for displaying information, such as embedding information icons from sensor payloads and external systems (e.g. other robots...

  16. Virtual Telescope Alignment System

    Data.gov (United States)

    National Aeronautics and Space Administration — Next-generation space telescopes require two spacecraft to fly in a coordinated fashion in space forming a virtual telescope. Achieving and maintaining this precise...

  17. Virtual Project Teams

    DEFF Research Database (Denmark)

    Bjørn, Pernille

    changes in both the technology structures and the collaborative practice; and 2) that establishing the social context within virtual project teams comprises negotiations of shared meaning bridging discontinuities typically associated with geographical distribution such as culture, work practices...... in virtual project teams whose members are spread across various geographical locations. The aim is to understand the specific factors, conditions and challenges underpinning such situations. This thesis describes, analyses and discusses three in-depth empirical studies on the practices and use of groupware...... technology in six real-life virtual teams, two in industry and four in education, applying interpretative research and action research methods. Two main lines of investigation are pursued: the first involves an examination of the organisational issues related to groupware adaptation in virtual project teams...

  18. Investigating Culture-related Aspects of Behavior for Virtual Characters

    DEFF Research Database (Denmark)

    Endrass, Birgit; André, Elisabeth; Rehm, Matthias

    2013-01-01

    In this paper, culture-related behaviors are investigated on several channels of communication for virtual characters. Prototypical behaviors were formalized in computational models based on a literature review as well as a corpus analysis, exemplifying the German and Japanese cultures. Therefore......, aspects of verbal behavior, communication management and nonverbal behavior were taken into account. In evaluation studies conducted in the targeted cultures, each aspect's impact on human observers was tested. With it, we investigated for which of the aspects, observers prefer agent behavior...... that was designed to resemble their own cultural background....

  19. Virtual Reality Lab Assistant

    Science.gov (United States)

    Saha, Hrishikesh; Palmer, Timothy A.

    1996-01-01

    Virtual Reality Lab Assistant (VRLA) demonstration model is aligned for engineering and material science experiments to be performed by undergraduate and graduate students in the course as a pre-lab simulation experience. This will help students to get a preview of how to use the lab equipment and run experiments without using the lab hardware/software equipment. The quality of the time available for laboratory experiments can be significantly improved through the use of virtual reality technology.

  20. Virtual reality musical instruments

    DEFF Research Database (Denmark)

    Serafin, Stefania; Erkut, Cumhur; Kojs, Juraj

    2016-01-01

    The rapid development and availability of low cost technologies has created a wide interest in virtual reality (VR), but how to design and evaluate multisensory interactions in VR remains as a challenge. In this paper, we focus on virtual reality musical instruments, present an overview of our...... design and evaluation guidelines, and examine historical case studies. Our main contribution is to inform the design and evaluation of the future VRMIs and consider the challenges....

  1. 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.

  2. Dosimetric perturbation due to scattered rays released by a gold marker used for tumor tracking in external radiotherapy

    International Nuclear Information System (INIS)

    Habara, Kosaku; Furukawa, Takashi; Shimozato, Tomohiro; Obata, Yasunori; Aoyama, Yuichi; Kawanami, Ryota; Hayashi, Naoki; Yasui, Keisuke; Matsuura, Kanji

    2011-01-01

    Image-guided radiation therapy using a gold marker-based tumor tracking technique provides precise patient setup and monitoring. However, the marker consists of high-Z material, and the resulting scattered rays tend to have adverse effects on the dose distribution of radiotherapy. The purpose of this study was to evaluate the dosimetric perturbation due to the use of a gold marker for radiotherapy in the lungs. The relative dose distributions were compared with film measurement, Monte Carlo simulation, and XiO calculation with the multi grid superposition algorithm using two types of virtual lung phantoms, which were composed of tough water phantoms, tough lung phantoms, cork boards, and a 2.0-mm-diameter gold ball. No dose increase and decrease in the vicinity of the gold ball was seen in the XiO calculations, although it was seen in the film measurements and the Monte Carlo simulation. The dose perturbation due to a gold marker cannot be evaluated using XiO calculation with the superposition algorithm when the tumor is near a gold marker (especially within 0.5 cm). To rule out the presence of such dose perturbations due to a gold marker, the distance between the gold marker and the tumor must therefore be greater than 0.5 cm. (author)

  3. Household and familial resemblance in risk factors for type 2 diabetes and related cardiometabolic diseases in rural Uganda sample

    DEFF Research Database (Denmark)

    Nielsen, Jannie; Bahendeka, Silver K.; Whyte, Susan R.

    2017-01-01

    (ICC=0.24), HbA1c (ICC=0.18) and systolic blood pressure (ICC=0.11). Regarding dyadic resemblance, the highest standardised regression coefficient was seen in fitness status for spouses (0.54, 95% CI 0.32 to 0.76), parent–offspring (0.41, 95% CI 0.28 0.54) and siblings (0.41, 95% CI 0.25 to 0.......57). Overall, parent–offspring and sibling pairs were the dyads with strongest resemblance, followed by spouses. Conclusions The marked degree of resemblance in T2D risk factors at household level and between spouses, parent–offspring and sibling dyads suggest that shared behavioural and environmental factors...

  4. Virtual Prototyping at CERN

    Science.gov (United States)

    Gennaro, Silvano De

    The VENUS (Virtual Environment Navigation in the Underground Sites) project is probably the largest Virtual Reality application to Engineering design in the world. VENUS is just over one year old and offers a fully immersive and stereoscopic "flythru" of the LHC pits for the proposed experiments, including the experimental area equipment and the surface models that are being prepared for a territorial impact study. VENUS' Virtual Prototypes are an ideal replacement for the wooden models traditionally build for the past CERN machines, as they are generated directly from the EUCLID CAD files, therefore they are totally reliable, they can be updated in a matter of minutes, and they allow designers to explore them from inside, in a one-to-one scale. Navigation can be performed on the computer screen, on a stereoscopic large projection screen, or in immersive conditions, with an helmet and 3D mouse. By using specialised collision detection software, the computer can find optimal paths to lower each detector part into the pits and position it to destination, letting us visualize the whole assembly probess. During construction, these paths can be fed to a robot controller, which can operate the bridge cranes and build LHC almost without human intervention. VENUS is currently developing a multiplatform VR browser that will let the whole HEP community access LHC's Virtual Protoypes over the web. Many interesting things took place during the conference on Virtual Reality. For more information please refer to the Virtual Reality section.

  5. Virtualization Technologies for the Business

    OpenAIRE

    Sabina POPESCU

    2011-01-01

    There is a new trend of change in today's IT industry. It's called virtualization. In datacenter virtualization can occur on several levels, but the type of virtualization has created this trend change is the operating system offered or server virtualization. OS virtualization technologies come in two forms. First, there is a software component that is used to simulate a natural machine that has total control of an operating system operating on the host equipment. The second is a hypervisor, ...

  6. Sobre objetos y experiencias virtuales

    OpenAIRE

    Pacho, Julián

    2009-01-01

    This paper analyses basic onto-epistemological properties of the virtual reality and suggests these theses. First, the virtual reality establishes a new nature; its essential feature is to be an organic world of emancipated techno-theories. Second, the virtual reality doesn’t substitutes the traditional book; it substitutes the world. Third, the experience of the world in the virtual reality excludes the natural world experience. Fourth, the ontology of virtual reality is build without an act...

  7. Virtual Machine in Automation Projects

    OpenAIRE

    Xing, Xiaoyuan

    2010-01-01

    Virtual machine, as an engineering tool, has recently been introduced into automation projects in Tetra Pak Processing System AB. The goal of this paper is to examine how to better utilize virtual machine for the automation projects. This paper designs different project scenarios using virtual machine. It analyzes installability, performance and stability of virtual machine from the test results. Technical solutions concerning virtual machine are discussed such as the conversion with physical...

  8. 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.)

  9. 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.

  10. Parent–offspring resemblance in colony-specific adult survival of cliff swallows

    Science.gov (United States)

    Brown, Charles R.; Roche, Erin A.; Brown, Mary Bomberger

    2015-01-01

    Survival is a key component of fitness. Species that occupy discrete breeding colonies with different characteristics are often exposed to varying costs and benefits associated with group size or environmental conditions, and survival is an integrative net measure of these effects. We investigated the extent to which survival probability of adult (≥1-year old) cliff swallows (Petrochelidon pyrrhonota) occupying different colonies resembled that of their parental cohort and thus whether the natal colony had long-term effects on individuals. Individuals were cross-fostered between colonies soon after hatching and their presence as breeders monitored at colonies in the western Nebraska study area for the subsequent decade. Colony-specific adult survival probabilities of offspring born and reared in the same colony, and those cross-fostered away from their natal colony soon after birth, were positively and significantly related to subsequent adult survival of the parental cohort from the natal colony. This result held when controlling for the effect of natal colony size and the age composition of the parental cohort. In contrast, colony-specific adult survival of offspring cross-fostered to a site was unrelated to that of their foster parent cohort or to the cohort of non-fostered offspring with whom they were reared. Adult survival at a colony varied inversely with fecundity, as measured by mean brood size, providing evidence for a survival–fecundity trade-off in this species. The results suggest some heritable variation in adult survival, likely maintained by negative correlations between fitness components. The study provides additional evidence that colonies represent non-random collections of individuals.

  11. Image and Global Resemblance in the Light of Hadith “Who So Imitates other People Becomes One of Them”

    Directory of Open Access Journals (Sweden)

    SERDAR DEMİREL

    2016-06-01

    Full Text Available In today’s world, people from different countries, cities and institutions unprecedentedly resemble each other in every aspect of life. Likewise, the deeds and imagery aspirations of Oriental and Occidental people also resemble. In such an atmosphere, the local cultures rooted in history become accessories and lose their historical significance and metaphysical aspects in the edifice of the society. This study aims to analyze Prophet Muhammad’s (s.a.w. warning, “Who so imitates other people becomes one of them”, its layers of meaning and its relationship with “image and global resemblence”.

  12. 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.

  13. 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.

  14. 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.

  15. 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)

  16. Virtual Data in CMS Production

    CERN Document Server

    Arbree, A; Bourilkov, D; Cavanaugh, R J; Graham, G; Katageri, S; Rodríguez, J; Voeckler, J; Wilde, M

    2003-01-01

    Initial applications of the GriPhyN Chimera Virtual Data System have been performed within the context of CMS Production of Monte Carlo Simulated Data. The GriPhyN Chimera system consists of four primary components: 1) a Virtual Data Language, which is used to describe virtual data products, 2) a Virtual Data Catalog, which is used to store virtual data entries, 3) an Abstract Planner, which resolves all dependencies of a particular virtual data product and forms a location and existence independent plan, 4) a Concrete Planner, which maps an abstract, logical plan onto concrete, physical grid resources accounting for staging in/out files and publishing results to a replica location service. A CMS Workflow Planner, MCRunJob, is used to generate virtual data products using the Virtual Data Language. Subsequently, a prototype workflow manager, known as WorkRunner, is used to schedule the instantiation of virtual data products across a grid.

  17. Virtual data in CMS production

    International Nuclear Information System (INIS)

    Arbree, A. et al.

    2004-01-01

    Initial applications of the GriPhyN Chimera Virtual Data System have been performed within the context of CMS Production of Monte Carlo Simulated Data. The GriPhyN Chimera system consists of four primary components: (1) a Virtual Data Language, which is used to describe virtual data products, (2) a Virtual Data Catalog, which is used to store virtual data entries, (3) an Abstract Planner, which resolves all dependencies of a particular virtual data product and forms a location and existence independent plan, (4) a Concrete Planner, which maps an abstract, logical plan onto concrete, physical grid resources accounting for staging in/out files and publishing results to a replica location service. A CMS Workflow Planner, MCRunJob, is used to generate virtual data products using the Virtual Data Language. Subsequently, a prototype workflow manager, known as WorkRunner, is used to schedule the instantiation of virtual data products across a grid

  18. Familial Resemblance in Dietary Intakes of Children, Adolescents, and Parents: Does Dietary Quality Play a Role?

    Science.gov (United States)

    Bogl, Leonie H; Silventoinen, Karri; Hebestreit, Antje; Intemann, Timm; Williams, Garrath; Michels, Nathalie; Molnár, Dénes; Page, Angie S; Pala, Valeria; Papoutsou, Stalo; Pigeot, Iris; Reisch, Lucia A; Russo, Paola; Veidebaum, Toomas; Moreno, Luis A; Lissner, Lauren; Kaprio, Jaakko

    2017-08-17

    Information on familial resemblance is important for the design of effective family-based interventions. We aimed to quantify familial correlations and estimate the proportion of variation attributable to genetic and shared environmental effects (i.e., familiality) for dietary intake variables and determine whether they vary by generation, sex, dietary quality, or by the age of the children. The study sample consisted of 1435 families (1007 mothers, 438 fathers, 1035 daughters, and 1080 sons) from the multi-center I.Family study. Dietary intake was assessed in parents and their 2-19 years old children using repeated 24-h dietary recalls, from which the usual energy and food intakes were estimated with the U.S. National Cancer Institute Method. Food items were categorized as healthy or unhealthy based on their sugar, fat, and fiber content. Interclass and intraclass correlations were calculated for relative pairs. Familiality was estimated using variance component methods. Parent-offspring ( r = 0.11-0.33), sibling ( r = 0.21-0.43), and spouse ( r = 0.15-0.33) correlations were modest. Parent-offspring correlations were stronger for the intake of healthy ( r = 0.33) than unhealthy ( r = 0.10) foods. Familiality estimates were 61% (95% CI: 54-68%) for the intake of fruit and vegetables and the sum of healthy foods and only 30% (95% CI: 23-38%) for the sum of unhealthy foods. Familial factors explained a larger proportion of the variance in healthy food intake (71%; 95% CI: 62-81%) in younger children below the age of 11 than in older children equal or above the age of 11 (48%; 95% CI: 38-58%). Factors shared by family members such as genetics and/or the shared home environment play a stronger role in shaping children's intake of healthy foods than unhealthy foods. This suggests that family-based interventions are likely to have greater effects when targeting healthy food choices and families with younger children, and that other sorts of intervention are needed to

  19. NALCN ion channels have alternative selectivity filters resembling calcium channels or sodium channels.

    Directory of Open Access Journals (Sweden)

    Adriano Senatore

    Full Text Available NALCN is a member of the family of ion channels with four homologous, repeat domains that include voltage-gated calcium and sodium channels. NALCN is a highly conserved gene from simple, extant multicellular organisms without nervous systems such as sponges and placozoans and mostly remains a single gene compared to the calcium and sodium channels which diversified into twenty genes in humans. The single NALCN gene has alternatively-spliced exons at exons 15 or exon 31 that splices in novel selectivity filter residues that resemble calcium channels (EEEE or sodium channels (EKEE or EEKE. NALCN channels with alternative calcium, (EEEE and sodium, (EKEE or EEKE -selective pores are conserved in simple bilaterally symmetrical animals like flatworms to non-chordate deuterostomes. The single NALCN gene is limited as a sodium channel with a lysine (K-containing pore in vertebrates, but originally NALCN was a calcium-like channel, and evolved to operate as both a calcium channel and sodium channel for different roles in many invertebrates. Expression patterns of NALCN-EKEE in pond snail, Lymnaea stagnalis suggest roles for NALCN in secretion, with an abundant expression in brain, and an up-regulation in secretory organs of sexually-mature adults such as albumen gland and prostate. NALCN-EEEE is equally abundant as NALCN-EKEE in snails, but is greater expressed in heart and other muscle tissue, and 50% less expressed in the brain than NALCN-EKEE. Transfected snail NALCN-EEEE and NALCN-EKEE channel isoforms express in HEK-293T cells. We were not able to distinguish potential NALCN currents from background, non-selective leak conductances in HEK293T cells. Native leak currents without expressing NALCN genes in HEK-293T cells are NMDG(+ impermeant and blockable with 10 µM Gd(3+ ions and are indistinguishable from the hallmark currents ascribed to mammalian NALCN currents expressed in vitro by Lu et al. in Cell. 2007 Apr 20;129(2:371-83.

  20. Imaging manifestations of acquired elastopathy resembling pseudoxanthoma elasticum in patients with beta thalassaemia major and sickle cell disease

    International Nuclear Information System (INIS)

    Narayana, Harish; Cheng, Ken; Lau, Ken; Harish, Radhika; Bowden, Donald K.

    2016-01-01

    Development of an acquired systemic elastopathy resembling pseudoxanthoma elasticum in patients with chronic haemoglobinopathies such as beta thalassaemia major and sickle cell disease is well documented. There is paucity of any comprehensive literature on the radiological manifestations of this entity. This pictorial review aims to describe and illustrate the multi system and multi modality imaging findings of this condition.

  1. What's in a child's face? : effects of facial resemblance, love withdrawal, empathy and context on behavioral and neural responses

    NARCIS (Netherlands)

    Heckendorf, E.

    2018-01-01

    The aim of this thesis is to increase our knowledge of individual differences in the neural processing and appraisal of children’s faces that differ in their degree of resemblance with the participant’s face. Chapter 2 focuses on participants’ neural responses to child faces that differ in

  2. Varieties of virtualization

    Science.gov (United States)

    Ellis, Stephen R.

    1991-01-01

    Natural environments have a content, i.e., the objects in them; a geometry, i.e., a pattern of rules for positioning and displacing the objects; and a dynamics, i.e., a system of rules describing the effects of forces acting on the objects. Human interaction with most common natural environments has been optimized by centuries of evolution. Virtual environments created through the human-computer interface similarly have a content, geometry, and dynamics, but the arbitrary character of the computer simulation creating them does not insure that human interaction with these virtual environments will be natural. The interaction, indeed, could be supernatural but it also could be impossible. An important determinant of the comprehensibility of a virtual environment is the correspondence between the environmental frames of reference and those associated with the control of environmental objects. The effects of rotation and displacement of control frames of reference with respect to corresponding environmental references differ depending upon whether perceptual judgement or manual tracking performance is measured. The perceptual effects of frame of reference displacement may be analyzed in terms of distortions in the process of virtualizing the synthetic environment space. The effects of frame of reference displacement and rotation have been studied by asking subjects to estimate exocentric direction in a virtual space.

  3. Virtual Library: An essential component of virtual education

    Directory of Open Access Journals (Sweden)

    M zarghani

    2015-06-01

    Full Text Available Abstract Introduction: Library is one of the essential elements of universities which provide some important educational needs of students. Virtual education can not be exempted and virtual libraries are important support for virtual training programs. The purpose of this study is to evaluate the viewpoint of administrators and students in virtual education centers about the virtual library, its role and resources. Methods: This study was a descriptive survey. The research instrument was a researcher made questionnaire that its validity and reliability was confirmed. The study population consisted of 19 virtual training centers in Tehran city. Out of 19 centers, simple randomized sampling was done in five Centers. The sample size was 360 students. Data collection was conducted online and descriptive statistics using SPSS 18 and Excel software were used. Results: The results showed that viewpoints of administrators and students about the mission and services of virtual libraries in some cases were similar and in some cases were different. One of the administrators’ reasons for setting up a virtual learning system was lifelong learning, and lack of knowledge about virtual libraries was the reason for inadequate use of virtual libraries. The best format of virtual library from the administrators’ and students’ viewpoint, was portal document format (PDF. Conclusion: One of the most important function of a virtual library, is lifelong learning and empowering users to provide information and educational needs. The main reason for not setting up a virtual library is t lack of knowledge about it.

  4. 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

  5. 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...

  6. Utilization of surface active sites on gold in preparation of highly reactive interfaces for alcohols electrooxidation in alkaline media

    International Nuclear Information System (INIS)

    Cherevko, Serhiy; Kulyk, Nadiia; Chung, Chan-Hwa

    2012-01-01

    Graphical abstract: - Abstract: Pt/Au and Pd/Au surface interfaces show very high activity in electrocatalytic oxidation of alcohols in alkaline media. In this work, we present a method for preparation of such structures, which is based on galvanic displacement of the more noble gold with the less noble elements, and investigate their electrocatalytic properties. We propose that active states atoms on the surface of gold may be replaced with Pt and Pd. The generation of active sites on gold is achieved by cathodization in acidic solution. We show that depending on the cathodization time (active sites amount) gold surface electrochemistry changes from that resembling Au to the one typical for pure Pt. The Pt/Au structures prepared with a trace amount of platinum show extremely high electrocatalytic activity. The peak current of methanol oxidation on the Pt/Au electrode is more than an order of magnitude higher than that of the platinum film electrode and more than two orders of magnitude higher than that on the gold unactivated electrode. The difference in the peak current of ethanol oxidation between the Pt/Au and Pt electrodes is ca. 25 times. Moreover, similar deposition of Pt and Pd on active sites on high surface area gold prepared by hydrogen evolution assisted deposition and improved electrocatalytic properties of such structures toward alcohols oxidation is shown.

  7. 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

  8. Age and Gender Differences in Facial Attractiveness, but Not Emotion Resemblance, Contribute to Age and Gender Stereotypes

    Directory of Open Access Journals (Sweden)

    Rocco Palumbo

    2017-09-01

    Full Text Available Considerable research has shown effects of facial appearance on trait impressions and group stereotypes. We extended those findings in two studies that investigated the contribution of resemblance to emotion expressions and attractiveness to younger adults (YA and older adults (OA age and gender stereotypes on the dimensions of warmth and competence. Using connectionist modeling of facial metrics of 240 neutral younger and older faces, Study 1 found that, neutral expression older faces or female faces showed greater structural resemblance to happy expressions and less resemblance to angry expressions than did younger or male faces, respectively. In addition, neutral female faces showed greater resemblance to surprise expressions. In Study 2, YA and OA rated the faces of Study 1 for attractiveness and for 4 traits that we aggregated on the dimensions of competence (competent, healthy and warmth (trustworthy, not shrewd. We found that YA, but not OA, age stereotypes replicated previous research showing higher perceived warmth and lower perceived competence in older adults. In addition, previously documented gender stereotypes were moderated by face age for both YA and OA. The greater attractiveness of younger than older faces and female than male faces influenced age and gender stereotypes, including these deviations from prior research findings using category labels rather than faces. On the other hand, face age and face sex differences in emotion resemblance did not influence age or gender stereotypes, contrary to prediction. Our results provide a caveat to conclusions about age and gender stereotypes derived from responses to category labels, and they reveal the importance of assessing stereotypes with a methodology that is sensitive to influences of group differences in appearance that can exacerbate or mitigate stereotypes in more ecologically valid contexts. Although the gender differences in attractiveness in the present study may not have

  9. Age and Gender Differences in Facial Attractiveness, but Not Emotion Resemblance, Contribute to Age and Gender Stereotypes.

    Science.gov (United States)

    Palumbo, Rocco; Adams, Reginald B; Hess, Ursula; Kleck, Robert E; Zebrowitz, Leslie

    2017-01-01

    Considerable research has shown effects of facial appearance on trait impressions and group stereotypes. We extended those findings in two studies that investigated the contribution of resemblance to emotion expressions and attractiveness to younger adults (YA) and older adults (OA) age and gender stereotypes on the dimensions of warmth and competence. Using connectionist modeling of facial metrics of 240 neutral younger and older faces, Study 1 found that, neutral expression older faces or female faces showed greater structural resemblance to happy expressions and less resemblance to angry expressions than did younger or male faces, respectively. In addition, neutral female faces showed greater resemblance to surprise expressions. In Study 2, YA and OA rated the faces of Study 1 for attractiveness and for 4 traits that we aggregated on the dimensions of competence (competent, healthy) and warmth (trustworthy, not shrewd). We found that YA, but not OA, age stereotypes replicated previous research showing higher perceived warmth and lower perceived competence in older adults. In addition, previously documented gender stereotypes were moderated by face age for both YA and OA. The greater attractiveness of younger than older faces and female than male faces influenced age and gender stereotypes, including these deviations from prior research findings using category labels rather than faces. On the other hand, face age and face sex differences in emotion resemblance did not influence age or gender stereotypes, contrary to prediction. Our results provide a caveat to conclusions about age and gender stereotypes derived from responses to category labels, and they reveal the importance of assessing stereotypes with a methodology that is sensitive to influences of group differences in appearance that can exacerbate or mitigate stereotypes in more ecologically valid contexts. Although the gender differences in attractiveness in the present study may not have generalizability

  10. Hydrolytic Metallo-Nanozymes: From Micelles and Vesicles to Gold Nanoparticles

    Directory of Open Access Journals (Sweden)

    Fabrizio Mancin

    2016-08-01

    Full Text Available Although the term nanozymes was coined by us in 2004 to highlight the enzyme-like properties of gold nanoparticles passivated with a monolayer of Zn(II-complexes in the cleavage of phosphate diesters, systems resembling those metallo-nanoparticles, like micelles and vesicles, have been the subject of investigation since the mid-eighties of the last century. This paper reviews what has been done in the field and compares the different nanosystems highlighting the source of catalysis and frequent misconceptions found in the literature.

  11. Virtual-World Naturalism

    Directory of Open Access Journals (Sweden)

    Daniel Reynolds

    2010-07-01

    Full Text Available Sometimes a player will stray from the path described by a game, moving into new spaces, developing new possible modes of interaction, and often discovering the rougher edges of the game world, where physics models break down, textures become incongruous, and the pieces don’t quite fit together. Gameplay that seeks out these spaces and these phenomena, that searches for such clues to the underlying construction of the virtual environment, is a kind of virtual-world naturalism, at once a return to an investigative urge that has been subsumed to the exhaustive mapping and description of the real world and a form of resistance to the very idea of pre-defined paths of action, of externally imposed limits, in virtual worlds as well as in our own.

  12. Virtual Reality Musical Instruments

    DEFF Research Database (Denmark)

    Serafin, Stefania; Erkut, Cumhur; Kojs, Juraj

    2016-01-01

    The rapid development and availability of low-cost technologies have created a wide interest in virtual reality. In the field of computer music, the term “virtual musical instruments” has been used for a long time to describe software simulations, extensions of existing musical instruments......, and ways to control them with new interfaces for musical expression. Virtual reality musical instruments (VRMIs) that include a simulated visual component delivered via a head-mounted display or other forms of immersive visualization have not yet received much attention. In this article, we present a field...... overview of VRMIs from the viewpoint of the performer. We propose nine design guidelines, describe evaluation methods, analyze case studies, and consider future challenges....

  13. First Indico Virtual Event

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    The first Indico virtual event will take place on February 4th 15:00 and will focus on two main topics The release of Indico v1.2 The migration of the OO Indico backend database (ZODB) to a more standard DBMS It will be fully virtual using the CERN Vidyo service and will foster discussions between developers and administrators of Indico servers worldwide. Connections to the virtual room will be open, but attendees are encouraged to register to the event, in order to be informed of any changes in the organisation if any. If you would like to add a topic of discussion or propose yourself a contribution, please let us know at indico-team@cern.ch. Connection to Vidyo Vidyo connection details are available here CERN Vidyo service documentation can be found here First-time users are encouraged to try the service before connecting to the real event

  14. The assessment of Attention Deficit Hyperactivity Disorder in children using continous performance tasks in virtual environments

    OpenAIRE

    Gutiérrez Maldonado, José; Letosa Porta, A.; Rus Calafell, M.; Peñaloza Salazar, C.

    2009-01-01

    The assessment of Attention-Deficit/Hyperactivity Disorder (ADHD) involves the use of different instruments, and one of the most frequently used is the Continuous Performance Test (CPT). Virtual reality allows for the achieving of the presentation of stimuli with high levels of control. In addition, it facilitates the presentation of distracters with a high level of resemblance to elements which in fact can be found in the real world by placing them in a similar context. Thus, it is possible ...

  15. Effects of Virtual Reality Immersion and Audiovisual Distraction Techniques for Patients with Pruritus

    Directory of Open Access Journals (Sweden)

    Vera Leibovici

    2009-01-01

    Full Text Available BACKGROUND: Virtual reality immersion (VRI, an advanced computer-generated technique, decreased subjective reports of pain in experimental and procedural medical therapies. Furthermore, VRI significantly reduced pain-related brain activity as measured by functional magnetic resonance imaging. Resemblance between anatomical and neuroendocrine pathways of pain and pruritus may prove VRI to be a suitable adjunct for basic and clinical studies of the complex aspects of pruritus.

  16. 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 ...

  17. 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

  18. Virtual or Virtually U: Educational Institutions in Second Life

    OpenAIRE

    Nancy Jennings; Chris Collins

    2007-01-01

    Educational institutions are increasingly exploring the affordances of 3D virtual worlds for instruction and research, but few studies have been done to document current practices and uses of this emerging technology. This observational survey examines the virtual presences of 170 accredited educational institutions found in one such 3D virtual world called Second Life®, created by San- Francisco based Linden Lab®. The study focuses on what educational institutions look like in this virtual e...

  19. Cytochrome C Dynamics at Gold and Glassy Carbon Surfaces Monitored by in Situ Scanning Tunnel Microscopy

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov; Møller, Per; Pedersen, Marianne Vind

    1995-01-01

    We have investigated the absorption of cytochrome c on gold and glassy carbon substrates by in situ scanning tunnel microscopy under potentiostatic control of both substrate and tip. Low ionic strength and potential ranges where no Faradaic current flows were used. Cyt c aggregates into flat...... composite structures of about 50 nm lateral extension at gold surfaces. The aggregates evolve in time, and structures resembling individual cyt c molecules can be distinguished in the space between the 50 nm structures. Cyt c aggregates also form at glassy carbon but have a different, unbroken character...... where cyt c both sticks well to the surface and exhibits notable mobility. The observations suggest that characteristic surface specific, internally mobile protein aggregates are formed at both surfaces and that in situ molecular resolution of the STM pictures may have been achieved....

  20. The virtual knife

    DEFF Research Database (Denmark)

    Hansen, Mads Fogtmann

    and order books. The Danish Meat Research Institute (DMRI) is currently constructing a representative database of virtual representations of pigs using X-ray Computed Tomography (CT). The database will serve as the foundation for the diversity modeling of pigs and for extracting predictors of quality...... and optimal use. This thesis integrates well-known techniques from the medical image analysis into the development of tools for automated analysis of the morphology of pigs. E.g. elastic image matching has been applied to establish spatial correspondence between the virtual representations of pigs...

  1. Coded Network Function Virtualization

    DEFF Research Database (Denmark)

    Al-Shuwaili, A.; Simone, O.; Kliewer, J.

    2016-01-01

    Network function virtualization (NFV) prescribes the instantiation of network functions on general-purpose network devices, such as servers and switches. While yielding a more flexible and cost-effective network architecture, NFV is potentially limited by the fact that commercial off-the-shelf ha......Network function virtualization (NFV) prescribes the instantiation of network functions on general-purpose network devices, such as servers and switches. While yielding a more flexible and cost-effective network architecture, NFV is potentially limited by the fact that commercial off...

  2. Virtual realities and education

    Directory of Open Access Journals (Sweden)

    Curcio Igor D.D.

    2016-12-01

    Full Text Available The purpose of this article is to highlight the state of the art of virtual reality, augmented reality, mixed reality technologies and their applications in formal education. We also present a selected list of case studies that prove the utility of these technologies in the context of formal education. Furthermore, as byproduct, the mentioned case studies show also that, although the industry is able to develop very advanced virtual environment technologies, their pedagogical implications are strongly related to a well-designed theoretical framework.

  3. Laboratorios virtuales colaborativos

    OpenAIRE

    Jara, Carlos A.; Candelas-Herías, Francisco A.; Torres, Fernando; Dormido Bencomo, Sebastián; Esquembre Martínez, Francisco

    2008-01-01

    Comunicación presentada en las XXIX Jornadas de Automática, Tarragona, 3-5 Septiembre 2008. El uso del laboratorio virtual (LV) como herramienta para el aprendizaje y experimentación práctica a distancia, cada vez es mayor en el entorno de educación superior. Este objeto de enseñanza virtual representa actualmente una revolución dentro del ámbito educativo, ya que permite adquirir al alumno habilidades prácticas desde cualquier lugar y en cualquier momento. Por otro lado, el desarrollo ...

  4. Virtual reality haptic dissection.

    Science.gov (United States)

    Erolin, Caroline; Wilkinson, Caroline; Soames, Roger

    2011-12-01

    This project aims to create a three-dimensional digital model of the human hand and wrist which can be virtually 'dissected' through a haptic interface. Tissue properties will be added to the various anatomical structures to replicate a realistic look and feel. The project will explore the role of the medical artist, and investigate cross-discipline collaborations in the field of virtual anatomy. The software will be used to train anatomy students in dissection skills, before experience on a real cadaver. The effectiveness of the software will be evaluated and assessed both quantitatively as well as qualitatively.

  5. Designing Virtual Learning Centers

    OpenAIRE

    Paquette, Gilbert

    2002-01-01

    - This paper is a pre-print version of the article whose definitive version can be found on http://www.springer.com/east/home/generic/search/results?SGWID=5-40109-22-2122620-0. Please cite the full reference when referring to the article. - This article is an extended version of a key-note presentation at the Ed-Media 2000 conference.; Virtual universities and work-place virtual institutes are seen, more and more, as a solution to the huge education demand of the knowledge society. I will lim...

  6. Virtual power plant auctions

    International Nuclear Information System (INIS)

    Ausubel, Lawrence M.; Cramton, Peter

    2010-01-01

    Since their advent in 2001, virtual power plant (VPP) auctions have been implemented widely. In this paper, we describe the simultaneous ascending-clock auction format that has been used for virtually all VPP auctions to date, elaborating on other design choices that most VPP auctions have had in common as well as discussing a few aspects that have varied significantly among VPP auctions. We then evaluate the various objectives of regulators in requiring VPP auctions, concluding that the auctions have been effective devices for facilitating new entry into electricity markets and for developing wholesale power markets. (author)

  7. Virtual power plant auctions

    Energy Technology Data Exchange (ETDEWEB)

    Ausubel, Lawrence M.; Cramton, Peter [Department of Economics, University of Maryland, College Park, MD 20742 (United States)

    2010-12-15

    Since their advent in 2001, virtual power plant (VPP) auctions have been implemented widely. In this paper, we describe the simultaneous ascending-clock auction format that has been used for virtually all VPP auctions to date, elaborating on other design choices that most VPP auctions have had in common as well as discussing a few aspects that have varied significantly among VPP auctions. We then evaluate the various objectives of regulators in requiring VPP auctions, concluding that the auctions have been effective devices for facilitating new entry into electricity markets and for developing wholesale power markets. (author)

  8. A duet (virtually)

    OpenAIRE

    Waeckerlé, Emmanuelle

    2008-01-01

    My practice-based research explores language and related issues of place and identity, such as personal cultural borders and digital-human relationships on the edges of language. With A duo and A duet (virtually) I attempt to push further the interplay between the virtual and the real, and between the visual and sonic representations of my voice. In 2002 I created a unique vocal and visual instrument that I call VINST3, which responds not only to touch but to mood and sensibility. It cons...

  9. Applied virtual reality

    International Nuclear Information System (INIS)

    Yule, I.Y.; Lee, D.J.

    1996-01-01

    To reduce plant down time during irradiated fuel cell dismantling at Torness Power Station, a new visualisation technique has been used for the manipulator. Complex computer graphics packages were used to provide a ''Virtual Reality'' environment which allowed the Irradiated Fuel Dismantling Cell to be simulated. Significant cost savings have been achieved due to reductions in lost output. The virtual reality environment is at present being extended to the design and deployment of a new manipulator for in-vessel inspection of the boiler. (UK)

  10. 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 ...

  11. 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 ...

  12. 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.

  13. 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.

  14. 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...

  15. Universidades virtuales: ¿aprendizaje real?

    OpenAIRE

    Valenzuela González, Jaime R.

    2015-01-01

    1. Introducción; 2. Modalidades educativas; 3. Concepto y características de las universidades virtuales; 4. Un modelo de universidad virtual; 5. Universidades virtuales ¿aprendizaje real?; 6. Tensiones de las universidades virtuales; 7. Referencias

  16. Corporate Training in Virtual Worlds

    OpenAIRE

    Charles Nebolsky; Nicholas K. Yee; Valery A. Petrushin; Anatole V. Gershman

    2004-01-01

    This paper presents virtual training worlds that are relatively low-cost distributed collaborative learning environments suitable for corporate training. A virtual training world allows a facilitator, experts and trainees communicating and acting in the virtual environment for practicing skills during collaborative problem solving. Using these environments is beneficial to both trainees and corporations. Two system prototypes – the sales training and the leadership training virtual worl...

  17. Corporate Training in Virtual Worlds

    Directory of Open Access Journals (Sweden)

    Charles Nebolsky

    2004-12-01

    Full Text Available This paper presents virtual training worlds that are relatively low-cost distributed collaborative learning environments suitable for corporate training. A virtual training world allows a facilitator, experts and trainees communicating and acting in the virtual environment for practicing skills during collaborative problem solving. Using these environments is beneficial to both trainees and corporations. Two system prototypes – the sales training and the leadership training virtual worlds – are described. The leadership training course design is discussed in details.

  18. Virtual Museum Learning

    Science.gov (United States)

    Prosser, Dominic; Eddisford, Susan

    2004-01-01

    This paper examines children's and adults' attitudes to virtual representations of museum objects. Drawing on empirical research data gained from two web-based digital learning environments. The paper explores the characteristics of on-line learning activities that move children from a sense of wonder into meaningful engagement with objects and…

  19. Laboratorio virtual visual

    OpenAIRE

    Torres Medina, Fernando

    2010-01-01

    Presentación del Laboratorio Virtual Visual destinado a la simulación de algoritmos de visión artificial y procesamiento de imágenes desarrollado en el Grupo de Automática, Robótica y Visión Artificial de la Universidad de Alicante.

  20. A virtual nuclear world?

    International Nuclear Information System (INIS)

    Salve, R.

    1998-01-01

    The way in which virtual reality technology has so dramatically developed over the last few years has opened up the possibility of its application to various industrial processes. This article describes the possible uses of such a technique in nuclear power plants in various phases such as design, construction, operation or dismantling. (Author)

  1. Virtual Libraries: Service Realities.

    Science.gov (United States)

    Novak, Jan

    This paper discusses client service issues to be considered when transitioning to a virtual library situation. Themes related to the transitional nature of society in the knowledge era are presented, including: paradox and a contradictory nature; blurring of boundaries; networks, systems, and holistic thinking; process/not product, becoming/not…

  2. Virtual Libraries: Service Realities.

    Science.gov (United States)

    Novak, Jan

    2002-01-01

    Discussion of changes in society that have resulted from information and communication technologies focuses on changes in libraries and a new market for library services with new styles of clients. Highlights client service issues to be considered when transitioning to a virtual library situation. (Author/LRW)

  3. CMS Virtual Tour Greece

    CERN Document Server

    CERN. Geneva

    2014-01-01

    More than 500 high-school students from 7 locations in Greece visit virtually the CMS experiment. Read more about this record-breaking event here: http://home.web.cern.ch/students-educators/updates/2014/02/students-visit-heart-cms-detector

  4. Adaptivenes in Virtual Teams

    NARCIS (Netherlands)

    S. Qureshi (Sadja); D. Vogel

    2000-01-01

    textabstractComputer supported teams are capturing the attention of academics and practitioners as organisations increasingly put them into practice as virtual teams. The practical relevance of current research into computer supported teams could be increased if greater attention is paid to

  5. Virtual Interactive Space (VIS)

    DEFF Research Database (Denmark)

    Brooks, Anthony Lewis

    2015-01-01

    This paper shares code that enables the making of a Virtual Interactive Space (VIS) where the skin of the invisible active sensor area is dynamically responsive to the velocity of a limb e.g. hand. Used in proprioception training of movement the patch is at the core of the author’s Reafferentation...

  6. Virtual machine performance benchmarking.

    Science.gov (United States)

    Langer, Steve G; French, Todd

    2011-10-01

    The attractions of virtual computing are many: reduced costs, reduced resources and simplified maintenance. Any one of these would be compelling for a medical imaging professional attempting to support a complex practice on limited resources in an era of ever tightened reimbursement. In particular, the ability to run multiple operating systems optimized for different tasks (computational image processing on Linux versus office tasks on Microsoft operating systems) on a single physical machine is compelling. However, there are also potential drawbacks. High performance requirements need to be carefully considered if they are to be executed in an environment where the running software has to execute through multiple layers of device drivers before reaching the real disk or network interface. Our lab has attempted to gain insight into the impact of virtualization on performance by benchmarking the following metrics on both physical and virtual platforms: local memory and disk bandwidth, network bandwidth, and integer and floating point performance. The virtual performance metrics are compared to baseline performance on "bare metal." The results are complex, and indeed somewhat surprising.

  7. Alice - The Virtual Secretary

    DEFF Research Database (Denmark)

    Hansen, Thomas K.

    2009-01-01

    of the primary ideas behind using animated agents is, quoting Wik and Granström (2007), to transform the well-known desktop metaphor of the PC, into a more human metaphor, thereby increasing the authenticity of our interaction with technology. At Knowledge Lab we have combined three different technologies...... in order to create Alice – The virtual secretary....

  8. Adapting Virtual Camera Behaviour

    DEFF Research Database (Denmark)

    Burelli, Paolo

    2013-01-01

    In a three-dimensional virtual environment aspects such as narrative and interaction completely depend on the camera since the camera defines the player’s point of view. Most research works in automatic camera control aim to take the control of this aspect from the player to automatically gen...

  9. Definition of Virtual Levels.

    Science.gov (United States)

    Shore, Bruce W.

    1979-01-01

    Presents an examination of graphical displays of solutions to time-dependent Schrodinger equation modeling a laser-excited three-level atom. It suggests that an energy level may be regarded as virtual when it is detuned from resonance by more than two Rabi frequencies. (Author/HM)

  10. Virtual Reality and Education.

    Science.gov (United States)

    Helsel, Sandra

    1992-01-01

    Intended to provide a basic understanding of virtual reality (VR) from an educational perspective, this article describes the debate between conceptual and technological orientations to VR; the conceptual orientation to VR; technological definitions of VR, artificial reality, and cyberspace; dimensions of VR; and VR's impact on education. (11…

  11. Virtual Bridge Design Challenge

    Science.gov (United States)

    Mitts, Charles R.

    2013-01-01

    This design/problem-solving activity challenges students to design a replacement bridge for one that has been designated as either structurally deficient or functionally obsolete. The Aycock MS Technology/STEM Magnet Program Virtual Bridge Design Challenge is an authentic introduction to the engineering design process. It is a socially relevant…

  12. Virtual Environments 2005

    DEFF Research Database (Denmark)

    This book contains the proceedings of the joint 9th International Immersive Projection Technologies Workshop and the 11th EUROGRAPHICS Virtual Environments Workshop (IPTEGVE). The event was held in Aalborg, Denmark the 6. and 7. October 2005. It was organized at the VR Media Lab, Aalborg Universi...

  13. A realidade do virtual

    Directory of Open Access Journals (Sweden)

    Eduardo Simonini Lopes

    2005-06-01

    Full Text Available O presente trabalho propõe discutir o conceito de virtual, tendocomo apoio as obras de Pierre Lévy, Jean Baudrillard e Gilles Deleuze.Entendemos que diferentes propostas de realidade do virtualsurgem baseando-se na abordagem de cada um desses autores. E cadauma dessas propostas abre novas perspectivas para o pensamentode enxergar e manipular o conceito de virtual. Partimos, então,neste trabalho, do entendimento do virtual conquanto entidadedesterritorializada (Lévy, 1998, seguindo até sua compreensãoenquanto espaço de potência (Deleuze, 1996. Cada uma dessasabordagens produz um modo de pensar, e, enquanto Lévy situa ovirtual como o espaço de representação da consciência humana,Deleuze já o trabalha como dimensão de intensidades não representacionais, promotora de contínua diferença. Construímos, assim, uma reflexão sobre o modo como alguns pensadores têm trabalhadoo conceito de virtual: utilizando-o como recognição e ignorandoseu entendimento como potência.

  14. Building interactive virtual environments for simulated training in medicine using VRML and Java/JavaScript.

    Science.gov (United States)

    Korocsec, D; Holobar, A; Divjak, M; Zazula, D

    2005-12-01

    Medicine is a difficult thing to learn. Experimenting with real patients should not be the only option; simulation deserves a special attention here. Virtual Reality Modelling Language (VRML) as a tool for building virtual objects and scenes has a good record of educational applications in medicine, especially for static and animated visualisations of body parts and organs. However, to create computer simulations resembling situations in real environments the required level of interactivity and dynamics is difficult to achieve. In the present paper we describe some approaches and techniques which we used to push the limits of the current VRML technology further toward dynamic 3D representation of virtual environments (VEs). Our demonstration is based on the implementation of a virtual baby model, whose vital signs can be controlled from an external Java application. The main contributions of this work are: (a) outline and evaluation of the three-level VRML/Java implementation of the dynamic virtual environment, (b) proposal for a modified VRML Timesensor node, which greatly improves the overall control of system performance, and (c) architecture of the prototype distributed virtual environment for training in neonatal resuscitation comprising the interactive virtual newborn, active bedside monitor for vital signs and full 3D representation of the surgery room.

  15. A Virtual History of Mauritius

    African Journals Online (AJOL)

    admpather

    while offering numerous advantages over real reconstructions: Virtual Reconstructions. Historical reconstruction of the Aapravasi Ghat and the Grand Port Naval Battle will be considered and finally some preliminary work that has already been carried out will be presented. Keywords: Virtual Heritage, Virtual Reality, ...

  16. Team Development of Virtual Teams

    Science.gov (United States)

    Kim, Sooyoung

    2004-01-01

    Advanced technologies, globalization, the competitiveness of business, flexible working practices, and other rapid changes in the nature of work have all led to the booming of "virtual teams." This paper will provide an overview of virtual teams, including a description of their emergence, a definition and typology of the term "virtual team," an…

  17. Interacting with a Virtual Conductor

    NARCIS (Netherlands)

    Bos, P.; Reidsma, Dennis; Ruttkay, Z.M.; Nijholt, Antinus; Harper, R.; Rauterberg, M; Combetto, M.

    This paper presents a virtual embodied agent that can conduct musicians in a live performance. The virtual conductor conducts music specified by a MIDI file and uses input from a microphone to react to the tempo of the musicians. The current implementation of the virtual conductor can interact with

  18. [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.

  19. 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.

  20. 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)

  1. Virtual Sensor Test Instrumentation

    Science.gov (United States)

    Wang, Roy

    2011-01-01

    Virtual Sensor Test Instrumentation is based on the concept of smart sensor technology for testing with intelligence needed to perform sell-diagnosis of health, and to participate in a hierarchy of health determination at sensor, process, and system levels. A virtual sensor test instrumentation consists of five elements: (1) a common sensor interface, (2) microprocessor, (3) wireless interface, (4) signal conditioning and ADC/DAC (analog-to-digital conversion/ digital-to-analog conversion), and (5) onboard EEPROM (electrically erasable programmable read-only memory) for metadata storage and executable software to create powerful, scalable, reconfigurable, and reliable embedded and distributed test instruments. In order to maximize the efficient data conversion through the smart sensor node, plug-and-play functionality is required to interface with traditional sensors to enhance their identity and capabilities for data processing and communications. Virtual sensor test instrumentation can be accessible wirelessly via a Network Capable Application Processor (NCAP) or a Smart Transducer Interlace Module (STIM) that may be managed under real-time rule engines for mission-critical applications. The transducer senses the physical quantity being measured and converts it into an electrical signal. The signal is fed to an A/D converter, and is ready for use by the processor to execute functional transformation based on the sensor characteristics stored in a Transducer Electronic Data Sheet (TEDS). Virtual sensor test instrumentation is built upon an open-system architecture with standardized protocol modules/stacks to interface with industry standards and commonly used software. One major benefit for deploying the virtual sensor test instrumentation is the ability, through a plug-and-play common interface, to convert raw sensor data in either analog or digital form, to an IEEE 1451 standard-based smart sensor, which has instructions to program sensors for a wide variety of

  2. 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

  3. 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.

  4. Cognitive restraint, uncontrolled eating and emotional eating: correlations between parent and adolescent. : Familial resemblance in eating behavior

    OpenAIRE

    De Lauzon-Guillain , Blandine; Romon , Monique; Musher-Eizenman , Dara; Heude , Barbara; Basdevant , Arnaud; Charles , Marie-Aline

    2009-01-01

    International audience; The purpose of this study was to examine, in a general population, the resemblance in eating behaviour between adolescents and their parents. This study was based on the first examination of a community-based epidemiological study in Northern France. Subjects were offspring aged 14-22 years (135 boys and 125 girls) and their parents (174 fathers and 205 mothers). The Three-Factor Eating Questionnaire Revised 18-item version (TFEQ-R18) identified three aspects of eating...

  5. Age and Gender Differences in Facial Attractiveness, but Not Emotion Resemblance, Contribute to Age and Gender Stereotypes

    OpenAIRE

    Palumbo, Rocco; Adams, Reginald B.; Hess, Ursula; Kleck, Robert E.; Zebrowitz, Leslie

    2017-01-01

    Considerable research has shown effects of facial appearance on trait impressions and group stereotypes. We extended those findings in two studies that investigated the contribution of resemblance to emotion expressions and attractiveness to younger adults (YA) and older adults (OA) age and gender stereotypes on the dimensions of warmth and competence. Using connectionist modeling of facial metrics of 240 neutral younger and older faces, Study 1 found that, neutral expression older faces or f...

  6. Phanerozoic continental growth and gold metallogeny of Asia

    Science.gov (United States)

    Goldfarb, Richard J.; Taylor, Ryan D.; Collins, Gregory S.; Goryachev, Nicolay A.; Orlandini, Omero Felipe

    2014-01-01

    associated with ca. 150–125 Ma formation of important auriferous epithermal (Balei), skarn (Bystray), and porphyry (Kultuminskoe) deposits. In northeastern Russia, Early Cretaceous Pacific margin subduction and Late Cretaceous extension were associated with epithermal gold-deposit formation in the Uda–Murgal (Julietta) and Okhotsk–Chukotka (Dukat, Kupol) volcanic belts, respectively. In southeastern Russia, latest Cretaceous to Oligocene extension correlates with other low-sulfidation epithermal ores that formed in the East Sikhote–Alin volcanic belt. Other extensional events, likely related to changing plate dynamics along the Pacific margin of Asia, relate to epithermal–skarn–porphyry districts that formed at ca. 125–85 Ma in northeastmost China and ca. 105–90 Ma in the Coast Volcanic belt of SE China. The onset of strike slip along a part of the southeastern Pacific margin appears to correlate with the giant 148–135 Ma gold-rich porphyry–skarn province of the lower and middle Yangtze River. It is still controversial as to whether true Carlin-like gold deposits exist in Asia. Those deposits that most closely resemble the Nevada (USA) ores are those in the Permo-Triassic Youjiang basin of SW China and NE Vietnam, and are probably Late Triassic in age, although this is not certain. Other Carlin-like deposits have been suggested to exist in the Sepon basin of Laos and in the Mongol–Okhotsk region (Kuranakh) of Transbaikal.

  7. The dilemma of the Jiaodong gold deposits: Are they unique?

    Science.gov (United States)

    Goldfarb, Richard J.; Santosh, M.

    2013-01-01

    The ca. 126–120 Ma Au deposits of the Jiaodong Peninsula, eastern China, define the country's largest gold province with an overall endowment estimated as >3000 t Au. The vein and disseminated ores are hosted by NE- to NNE-trending brittle normal faults that parallel the margins of ca. 165–150 Ma, deeply emplaced, lower crustal melt granites. The deposits are sited along the faults for many tens of kilometers and the larger orebodies are associated with dilatational jogs. Country rocks to the granites are Precambrian high-grade metamorphic rocks located on both sides of a Triassic suture between the North and South China blocks. During early Mesozoic convergent deformation, the ore-hosting structures developed as ductile thrust faults that were subsequently reactivated during Early Cretaceous “Yanshanian” intracontinental extensional deformation and associated gold formation.Classification of the gold deposits remains problematic. Many features resemble those typical of orogenic Au including the linear structural distribution of the deposits, mineralization style, ore and alteration assemblages, and ore fluid chemistry. However, Phanerozoic orogenic Au deposits are formed by prograde metamorphism of accreted oceanic rocks in Cordilleran-style orogens. The Jiaodong deposits, in contrast, formed within two Precambrian blocks approximately 2 billion years after devolatilization of the country rocks, and thus require a model that involves alternative fluid and metal sources for the ores. A widespread suite of ca. 130–123 Ma granodiorites overlaps temporally with the ores, but shows a poor spatial association with the deposits. Furthermore, the deposit distribution and mineralization style is atypical of ores formed from nearby magmas. The ore concentration requires fluid focusing during some type of sub-crustal thermal event, which could be broadly related to a combination of coeval lithospheric thinning, asthenospheric upwelling, paleo-Pacific plate

  8. Art in virtual reality 2010

    Science.gov (United States)

    Chang, Ben

    2010-01-01

    For decades, virtual reality artwork has existed in a small but highly influential niche in the world of electronic and new media art. Since the early 1990's, virtual reality installations have come to define an extreme boundary point of both aesthetic experience and technological sophistication. Classic virtual reality artworks have an almost mythological stature - powerful, exotic, and often rarely exhibited. Today, art in virtual environments continues to evolve and mature, encompassing everything from fully immersive CAVE experiences to performance art in Second Life to the use of augmented and mixed reality in public space. Art in Virtual Reality 2010 is a public exhibition of new artwork that showcases the diverse ways that contemporary artists use virtual environments to explore new aesthetic ground and investigate the continually evolving relationship between our selves and our virtual worlds.

  9. 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...

  10. 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

  11. 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.

  12. 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 ...

  13. 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...

  14. 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

  15. 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.

  16. 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.

  17. Virtual Class Support at the Virtual Machine Level

    DEFF Research Database (Denmark)

    Nielsen, Anders Bach; Ernst, Erik

    2009-01-01

    This paper describes how virtual classes can be supported in a virtual machine.  Main-stream virtual machines such as the Java Virtual Machine and the .NET platform dominate the world today, and many languages are being executed on these virtual machines even though their embodied design choices...... conflict with the design choices of the virtual machine.  For instance, there is a non-trivial mismatch between the main-stream virtual machines mentioned above and dynamically typed languages.  One language concept that creates an even greater mismatch is virtual classes, in particular because fully...... general support for virtual classes requires generation of new classes at run-time by mixin composition.  Languages like CaesarJ and ObjectTeams can express virtual classes restricted to the subset that does not require run-time generation of classes, because of the restrictions imposed by the Java...

  18. Innovative application of virtual display technique in virtual museum

    Science.gov (United States)

    Zhang, Jiankang

    2017-09-01

    Virtual museum refers to display and simulate the functions of real museum on the Internet in the form of 3 Dimensions virtual reality by applying interactive programs. Based on Virtual Reality Modeling Language, virtual museum building and its effective interaction with the offline museum lie in making full use of 3 Dimensions panorama technique, virtual reality technique and augmented reality technique, and innovatively taking advantages of dynamic environment modeling technique, real-time 3 Dimensions graphics generating technique, system integration technique and other key virtual reality techniques to make sure the overall design of virtual museum.3 Dimensions panorama technique, also known as panoramic photography or virtual reality, is a technique based on static images of the reality. Virtual reality technique is a kind of computer simulation system which can create and experience the interactive 3 Dimensions dynamic visual world. Augmented reality, also known as mixed reality, is a technique which simulates and mixes the information (visual, sound, taste, touch, etc.) that is difficult for human to experience in reality. These technologies make virtual museum come true. It will not only bring better experience and convenience to the public, but also be conducive to improve the influence and cultural functions of the real museum.

  19. 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

  20. The Herbert Virtual Museum

    Directory of Open Access Journals (Sweden)

    Panagiotis Petridis

    2013-01-01

    Full Text Available In recent years, virtual reality and augmented reality have emerged as areas of extreme interest as unique methods for visualising and interacting with digital museum artefacts in a different context, for example, as a virtual museum or exhibition, particularly over the Internet. Modern cultural heritage exhibitions have evolved from static to dynamic exhibitions and challenging explorations. This paper presents two different applications developed for the Herbert Museum and Art Gallery that make the user’s experience more immersive, engaging, and interactive. The first application utilizes mobile phone devices in order to enrich the visitors experience in the museum, and the second application is a serious game for cultural heritage and in particular for museum environments focusing on the younger visitors.

  1. Virtual reality systems

    Science.gov (United States)

    Johnson, David W.

    1992-01-01

    Virtual realities are a type of human-computer interface (HCI) and as such may be understood from a historical perspective. In the earliest era, the computer was a very simple, straightforward machine. Interaction was human manipulation of an inanimate object, little more than the provision of an explicit instruction set to be carried out without deviation. In short, control resided with the user. In the second era of HCI, some level of intelligence and control was imparted to the system to enable a dialogue with the user. Simple context sensitive help systems are early examples, while more sophisticated expert system designs typify this era. Control was shared more equally. In this, the third era of the HCI, the constructed system emulates a particular environment, constructed with rules and knowledge about 'reality'. Control is, in part, outside the realm of the human-computer dialogue. Virtual reality systems are discussed.

  2. Interactive Virtual Cinematography

    DEFF Research Database (Denmark)

    Burelli, Paolo

    , if the content of the game is procedurally generated, the designer might not have the necessary information to dene a priori the camera positions and movements. Automatic camera control aims to dene an abstraction layer that permits to control the camera using high-level and environment-independent rules...... is the process of visualising the content of a virtual environment by positioning and animating the virtual camera in the context of interactive applications such as a computer game. Camera placement and animation in games are usually directly controlled by the player or statically predened by designers. Direct...... control of the camera by the player increases the complexity of the interaction and reduces the designer's control on game storytelling. A completely designer-driven camera releases the player from the burden of controlling the point of view, but might generate undesired camera behaviours. Furthermore...

  3. Material and Virtuality

    DEFF Research Database (Denmark)

    Kruse Aagaard, Anders

    2015-01-01

    world and a physical world can interchange. The paper suggest an approach where an overlapping of virtuality and the tangible material output from digital fabrication machines create a method of using materialisation tools as instruments to connect the reality of materials and to an exploring process....... In this paper investigations in sheet steel form a substance of concrete experiments. The experiments set up shuttling processes in between different domains. Through those processes connections and intermingling between information from digital drawing and materiality is created. The dialogues established...... through these experiments is both tangible and directly connected to real actions in digital drawing or material processing but also the base for theoretical contemplations of the relation between virtual and actual and control and uncertainty....

  4. Virtual vitreoretinal surgery

    DEFF Research Database (Denmark)

    Vergmann, Anna Stage; Vestergaard, Anders Højslet; Grauslund, Jakob

    2017-01-01

    PURPOSE: To test the validity of the eyesi surgical simulator as an assessment tool in a virtual reality vitreoretinal training programme. METHODS: In collaboration with an experienced vitreoretinal surgeon, a virtual vitreoretinal training programme was composed on the eyesi surgical simulator......, software version 2.9.2 (VRmagic GmbH, Manheim, Germany). It was completed twice by three groups: 20 medical students, ten residents of ophthalmology and five trained vitreoretinal surgeons. The programme contained six training modules: navigation level 2 (Nav2), forceps training level 5 (ForT5), bimanual...... training level 3 (BimT3), laser coagulation level 3 (LasC3), posterior hyaloid level 3 (PostH3) and internal limiting membrane peeling level 3 (ILMP3). The scores in each module were assessed from two to five different factors (tissue treatment, efficiency, target achievement, instrument handling...

  5. Virtual reality at work

    Science.gov (United States)

    Brooks, Frederick P., Jr.

    1991-01-01

    The utility of virtual reality computer graphics in telepresence applications is not hard to grasp and promises to be great. When the virtual world is entirely synthetic, as opposed to real but remote, the utility is harder to establish. Vehicle simulators for aircraft, vessels, and motor vehicles are proving their worth every day. Entertainment applications such as Disney World's StarTours are technologically elegant, good fun, and economically viable. Nevertheless, some of us have no real desire to spend our lifework serving the entertainment craze of our sick culture; we want to see this exciting technology put to work in medicine and science. The topics covered include the following: testing a force display for scientific visualization -- molecular docking; and testing a head-mounted display for scientific and medical visualization.

  6. Applied virtual reality

    International Nuclear Information System (INIS)

    Yule, I.Y.; Lee, D.J.

    1996-01-01

    An early experience in deploying a manipulator to the Irradiated Fuel Dismantling Cell at Torness Power Station, quickly highlighted that special visualisation techniques were required to achieve a successful deployment and reduce plant system down time. This visualisation was later realised through the IGRIP software pakcage operating on a Silicon Graphics computing engine, which provides a 'Non-Immersive' Virtual Reality environment. Within this environment, models of the Irradiated Fuel Dismantling cell were generated along with a model of the manipulator, allowing manipulator deployment to the Irradiated Fuel Dismantling Cell be modelled. It is estimated that the first use of this new environment provided a significant saving to Scottish Nuclear in potential lost output. The use of this virtual reality environment is currently being extended into the design and deployment of a new manipulator for Torness in vessel inspection, the Boiler Inspection Manipulator. (author)

  7. Virtual team collaboration

    DEFF Research Database (Denmark)

    Bjørn, Pernille; Ngwenyama, Ojelanki

    2009-01-01

    as the foundation for building shared meaning at three levels. Also we investigate communication breakdowns that can be attributed to differences in lifeworld structures, organizational structures, and work process structures within a virtual team. We find that all communication breakdowns are manifested...... and experienced by the participants at the work process level; however, resolving breakdowns may require critical reflection at other levels. Where previous research argues that face-to-face interaction is an important variable for virtual team performance, our empirical observations reveal that communication......Managing international teams with geographically distributed participants is a complex task. The risk of communication breakdowns increases due to cultural and organizational differences grounded in the geographical distribution of the participants. Such breakdowns indicate general...

  8. Virtual personal assistant

    OpenAIRE

    Imrie, Peter; Bednar, Peter

    2013-01-01

    Abstract This report discusses ways in which new technology could be harnessed to create an intelligent Virtual Personal Assistant (VPA) with a focus on user-based information. It will look at examples of intelligent programs with natural language processing that are currently available, with different categories of support, and examine the potential usefulness of one specific piece of software as a VPA. This engages the ability to communicate socially through natural language processing, hol...

  9. Droni e turismo virtuale

    Directory of Open Access Journals (Sweden)

    Valeria Minucciani

    2015-08-01

    Full Text Available Virtual tourism has been through at least three generations.The first is a special form of e-commerce, and no doubt it has much changed the way you plan your travel. Second generation of virtual tourism has exploited georeference: the user can know the services offered nearby and, with appropriate apps and augmented reality, receive information about places.An important contribution has been made in this field by social media (see Flickr, as well as Tripadvisor. The third generation of virtual tourism even replaces the travel experience: first proposing visits in virtual worlds, then in the real world. That allows tourism to social classes that are excluded.The goal is to send in the real place an "avatar", that can perform what tourist wants. Some experiments have been recently performed with robots, here a visit by drones is proposed. In particular, indoor visits are difficult because it is necessary to re-create a microgeodetic reference system in a closed and confined environment, to allow remote control and to ensure the protection of the cultural property. It has also to be considered the issue of the size of the drone, its autonomy and shooting video (which must be 360 degrees and high definition.The real experience is irreplaceable, but this form of tourism can find many interesting applications and strengthen real tourism.In conclusion, we believe that not only this performances are now within the reach of our technical capabilities, but  they also represent an effective response to certain social and cultural issues. 

  10. Virtual nuclear weapons

    Energy Technology Data Exchange (ETDEWEB)

    Pilat, J.F.

    1997-08-01

    The term virtual nuclear weapons proliferation and arsenals, as opposed to actual weapons and arsenals, has entered in recent years the American lexicon of nuclear strategy, arms control, and nonproliferation. While the term seems to have an intuitive appeal, largely due to its cyberspace imagery, its current use is still vague and loose. The author believes, however, that if the term is clearly delineated, it might offer a promising approach to conceptualizing certain current problems of proliferation. The first use is in a reference to an old problem that has resurfaced recently: the problem of growing availability of weapon-usable nuclear materials in civilian nuclear programs along with materials made `excess` to defense needs by current arms reduction and dismantlement. It is argued that the availability of these vast materials, either by declared nuclear-weapon states or by technologically advanced nonweapon states, makes it possible for those states to rapidly assemble and deploy nuclear weapons. The second use has quite a different set of connotations. It is derived conceptually from the imagery of computer-generated reality. In this use, one thinks of virtual proliferation and arsenals not in terms of the physical hardware required to make the bomb but rather in terms of the knowledge/experience required to design, assemble, and deploy the arsenal. Virtual weapons are a physics reality and cannot be ignored in a world where knowledge, experience, materials, and other requirements to make nuclear weapons are widespread, and where dramatic army reductions and, in some cases, disarmament are realities. These concepts are useful in defining a continuum of virtual capabilities, ranging from those at the low end that derive from general technology diffusion and the existence of nuclear energy programs to those at the high end that involve conscious decisions to develop or maintain militarily significant nuclear-weapon capabilities.

  11. Virtual Reality Spectating

    OpenAIRE

    Hemb, Jan Greger

    2017-01-01

    The goal of this master was to assess and evaluate Virtual Reality (VR) spectating. VR spectating refers to spectating someone playing a game in VR. A series of spectating modes (mirroring, 3D and VR) was assessed in a series of experiments, and user testing sessions to determine the preferred mode for spectating VR content. A range of related topics were discussed as well, including spectator placement models, streamers core success values, and the projected success of VR as a platform. ...

  12. Virtual Environments Overview

    Science.gov (United States)

    2009-04-01

    digital form. McQuail , D (2000) McQuail’s Mass Communication Theory (4th edition), Sage, London, pp. 16-34. 5 2. AFFORDANCES OF VIRTUAL... S . (1991). “Grounding in Communication .” In Resnick, L.B., Levine, J., Teasley, S . (Eds.). Perspectives on Socially Shared Cognition. Washington DC...www.cia.gov/library/center-for-the-study-of-intelligence/csi-publications/books-and- monographs/analytic-culture-in-the-u- s -intelligence- community

  13. The virtual oil company

    International Nuclear Information System (INIS)

    Garibaldi, C.A.; Haney, R.M.; Ross, C.E.

    1995-01-01

    In anticipation of continuing declines in upstream activity levels over the next 15 years, the virtual oil company model articulates a vision of fewer, leaner, but financially stronger firms that concentrate only on their core competencies and outsource the rest through well-structured partnering arrangements. Freed from the ''clutter,'' these leading companies will be in better position to focus on those opportunities that offer the potential for renewed reserve and revenue growth

  14. Virtual private network (VPN)

    International Nuclear Information System (INIS)

    Caskey, Susan

    2006-01-01

    A virtual private network (VPN) is the essential security feature that allows remote monitoring systems to take advantage of the low communications cost of the internet. This paper introduces the VPN concept and summarizes the networking and security principles. The mechanics of security, for example, types of encryption and protocols for exchange of keys between partners, are explained. Important issues for partners in different countries include the interoperability and mutual accreditations of systems. (author)

  15. Droni e turismo virtuale

    Directory of Open Access Journals (Sweden)

    Valeria Minucciani

    2015-08-01

    Full Text Available Virtual tourism has been through at least three generations. The first is a special form of e-commerce, and no doubt it has much changed the way you plan your travel. Second generation of virtual tourism has exploited georeference: the user can know the services offered nearby and, with appropriate apps and augmented reality, receive information about places. An important contribution has been made in this field by social media (see Flickr, as well as Tripadvisor. The third generation of virtual tourism even replaces the travel experience: first proposing visits in virtual worlds, then in the real world. That allows tourism to social classes that are excluded. The goal is to send in the real place an "avatar", that can perform what tourist wants. Some experiments have been recently performed with robots, here a visit by drones is proposed. In particular, indoor visits are difficult because it is necessary to re-create a microgeodetic reference system in a closed and confined environment, to allow remote control and to ensure the protection of the cultural property. It has also to be considered the issue of the size of the drone, its autonomy and shooting video (which must be 360 degrees and high definition. The real experience is irreplaceable, but this form of tourism can find many interesting applications and strengthen real tourism. In conclusion, we believe that not only this performances are now within the reach of our technical capabilities, but  they also represent an effective response to certain social and cultural issues.

  16. Virtual Reality in Neurorehabilitation

    OpenAIRE

    Stasieńko Agnieszka; Sarzyńska-Długosz Iwona

    2016-01-01

    This article includes current information on the use of modern IT solutions and virtual-reality (VR)-based technologies in medical rehabilitation. A review of current literature on VR-based interventions and their indications, benefits and limitations in patients with nervous system diseases was conducted. The popularity of VR-based training as a tool used for rehabilitation of patients with acute and chronic deficits in both sensory-motor and cognitive disorders is increasing. Still, there i...

  17. Tele Hyper Virtuality

    Science.gov (United States)

    Terashima, Nobuyoshi

    1994-01-01

    In the future, remote images sent over communication lines will be reproduced in virtual reality (VR). This form of virtual telecommunications, which will allow observers to engage in an activity as though it were real, is the focus of considerable attention. Taken a step further, real and unreal objects will be placed in a single space to create an extremely realistic environment. Here, imaginary and other life forms as well as people and animals in remote locations will gather via telecommunication lines that create a common environment where life forms can work and interact together. Words, gestures, diagrams and other forms of communication will be used freely in performing work. Actual construction of a system based on this new concept will not only provide people with experiences that would have been impossible in the past, but will also inspire new applications in which people will function in environments where it would have been difficult if not impossible for them to function until now. This paper describes Tele Hyper Virtuality concept, its definition, applications, the key technologies to accomplish it and future prospects.

  18. Medical Virtual Public Services

    Directory of Open Access Journals (Sweden)

    Iulia SURUGIU

    2008-01-01

    Full Text Available The healthcare enterprises are very disconnected. This paper intends to propose a solution that will provide citizens, businesses and medical enterprises with improved access to medical virtual public services. Referred medical services are based on existing national medical Web services and which support medically required services provided by physicians and supplementary health care practitioners, laboratory services and diagnostic procedures, clinics and hospitals’ services. Requirements and specific rules of these medical services are considered, and personalization of user preferences will to be supported. The architecture is based on adaptable process management technologies, allowing for virtual services which are dynamically combined from existing national medical services. In this way, a comprehensive workflow process is set up, allowing for service-level agreements, an audit trail and explanation of the process to the end user. The process engine operates on top of a virtual repository, providing a high-level semantic view of information retrieved from heterogeneous information sources, such as national sources of medical services. The system relies on a security framework to ensure all high-level security requirements are met. System’s architecture is business oriented: it focuses on Service Oriented Architecture - SOA concepts, asynchronously combining Web services, Business Process Management – BPM rules and BPEL standards.

  19. The virtual articulator.

    Science.gov (United States)

    Bisler, A; Bockholt, U; Kordass, B; Suchan, M; Voss, G

    2002-01-01

    The virtual articulator (VA) is intended for use as a tool for the analysis fo the complex static and dynamic occlusal relations. Its chief application is in individual diagnosis and the simulation of the mechanical articulator. As entry data, the VA requires digital, 3-dimensional representations of the jaws and patient-specific data on jaw movement. It then simulates jaw movement and provides a dynamic visualization of the occlusal contacts. If no patient-specific data are available, the modus operandi of the mechanical articulator can be simulated. Virtual reality (VR) techniques applied in computer-aided diagnosis are revolutionizing medical routine in many disciplines. Particularly in the field of dental engineering, VR combined with CAD/CAM technology has great potential in implant planning and design in terms of greater precision and shorter treatment duration. The geometry of teeth can be digitized, the implant models can be designed with specialized CAD systems, and the final implants can be manufactured with a CNC machine. In this context, the virtual articulator completes the digital manufacturing process.

  20. Virtual blood bank

    Directory of Open Access Journals (Sweden)

    Kit Fai Wong

    2011-01-01

    Full Text Available Virtual blood bank is the computer-controlled, electronically linked information management system that allows online ordering and real-time, remote delivery of blood for transfusion. It connects the site of testing to the point of care at a remote site in a real-time fashion with networked computers thus maintaining the integrity of immunohematology test results. It has taken the advantages of information and communication technologies to ensure the accuracy of patient, specimen and blood component identification and to enhance personnel traceability and system security. The built-in logics and process constraints in the design of the virtual blood bank can guide the selection of appropriate blood and minimize transfusion risk. The quality of blood inventory is ascertained and monitored, and an audit trail for critical procedures in the transfusion process is provided by the paperless system. Thus, the virtual blood bank can help ensure that the right patient receives the right amount of the right blood component at the right time.

  1. Virtual blood bank

    Science.gov (United States)

    Wong, Kit Fai

    2011-01-01

    Virtual blood bank is the computer-controlled, electronically linked information management system that allows online ordering and real-time, remote delivery of blood for transfusion. It connects the site of testing to the point of care at a remote site in a real-time fashion with networked computers thus maintaining the integrity of immunohematology test results. It has taken the advantages of information and communication technologies to ensure the accuracy of patient, specimen and blood component identification and to enhance personnel traceability and system security. The built-in logics and process constraints in the design of the virtual blood bank can guide the selection of appropriate blood and minimize transfusion risk. The quality of blood inventory is ascertained and monitored, and an audit trail for critical procedures in the transfusion process is provided by the paperless system. Thus, the virtual blood bank can help ensure that the right patient receives the right amount of the right blood component at the right time. PMID:21383930

  2. 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.

  3. 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.

  4. Framework for Virtual Cognitive Experiment in Virtual Geographic Environments

    OpenAIRE

    Fan Zhang; Mingyuan Hu; Weitao Che; Hui Lin; Chaoyang Fang

    2018-01-01

    Virtual Geographic Environment Cognition is the attempt to understand the human cognition of surface features, geographic processes, and human behaviour, as well as their relationships in the real world. From the perspective of human cognition behaviour analysis and simulation, previous work in Virtual Geographic Environments (VGEs) has focused mostly on representing and simulating the real world to create an ‘interpretive’ virtual world and improve an individual’s active cognition. In terms ...

  5. 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.

  6. 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

  7. 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)

  8. 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

  9. 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...

  10. 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.

  11. Using a Virtual Store As a Research Tool to Investigate Consumer In-store Behavior.

    Science.gov (United States)

    Ploydanai, Kunalai; van den Puttelaar, Jos; van Herpen, Erica; van Trijp, Hans

    2017-07-24

    People's responses to products and/or choice environments are crucial to understanding in-store consumer behaviors. Currently, there are various approaches (e.g., surveys or laboratory settings) to study in-store behaviors, but the external validity of these is limited by their poor capability to resemble realistic choice environments. In addition, building a real store to meet experimental conditions while controlling for undesirable effects is costly and highly difficult. A virtual store developed by virtual reality techniques potentially transcends these limitations by offering the simulation of a 3D virtual store environment in a realistic, flexible, and cost-efficient way. In particular, a virtual store interactively allows consumers (participants) to experience and interact with objects in a tightly controlled yet realistic setting. This paper presents the key elements of using a desktop virtual store to study in-store consumer behavior. Descriptions of the protocol steps to: 1) build the experimental store, 2) prepare the data management program, 3) run the virtual store experiment, and 4) organize and export data from the data management program are presented. The virtual store enables participants to navigate through the store, choose a product from alternatives, and select or return products. Moreover, consumer-related shopping behaviors (e.g., shopping time, walking speed, and number and type of products examined and bought) can also be collected. The protocol is illustrated with an example of a store layout experiment showing that shelf length and shelf orientation influence shopping- and movement-related behaviors. This demonstrates that the use of a virtual store facilitates the study of consumer responses. The virtual store can be especially helpful when examining factors that are costly or difficult to change in real life (e.g., overall store layout), products that are not presently available in the market, and routinized behaviors in familiar

  12. Framework for Virtual Cognitive Experiment in Virtual Geographic Environments

    Directory of Open Access Journals (Sweden)

    Fan Zhang

    2018-01-01

    Full Text Available Virtual Geographic Environment Cognition is the attempt to understand the human cognition of surface features, geographic processes, and human behaviour, as well as their relationships in the real world. From the perspective of human cognition behaviour analysis and simulation, previous work in Virtual Geographic Environments (VGEs has focused mostly on representing and simulating the real world to create an ‘interpretive’ virtual world and improve an individual’s active cognition. In terms of reactive cognition, building a user ‘evaluative’ environment in a complex virtual experiment is a necessary yet challenging task. This paper discusses the outlook of VGEs and proposes a framework for virtual cognitive experiments. The framework not only employs immersive virtual environment technology to create a realistic virtual world but also involves a responsive mechanism to record the user’s cognitive activities during the experiment. Based on the framework, this paper presents two potential implementation methods: first, training a deep learning model with several hundred thousand street view images scored by online volunteers, with further analysis of which visual factors produce a sense of safety for the individual, and second, creating an immersive virtual environment and Electroencephalogram (EEG-based experimental paradigm to both record and analyse the brain activity of a user and explore what type of virtual environment is more suitable and comfortable. Finally, we present some preliminary findings based on the first method.

  13. Socioeconomic and Demographic Factors for Spousal Resemblance in Obesity Status and Habitual Physical Activity in the United States

    Directory of Open Access Journals (Sweden)

    Hsin-Jen Chen

    2014-01-01

    Full Text Available Studies suggested that the married population has an increased risk of obesity and assimilation between spouses’ body weight. We examined what factors may affect married spouses’ resemblance in weight status and habitual physical activity (HPA and the association of obesity/HPA with spouses’ sociodemoeconomic characteristics and lifestyles. Medical Expenditure Panel Survey data of 11,403 adult married couples in the US during years 2006–2008 were used. Absolute-scale difference and relative-scale resemblance indices (correlation and kappa coefficients in body mass index (BMI and HPA were estimated by couples’ socioeconomic and demographic characteristics. We found that spousal difference in BMI was smaller for couples with a lower household income, for who were both unemployed, and for older spouses. Correlation coefficient between spouses’ BMI was 0.24, differing by race/ethnicity and family size. Kappa coefficient for weight status (obesity: BMI ≥ 30, overweight: 30 > BMI ≥ 25 was 0.11 and 0.35 for HPA. Never-working women’s husbands had lower odds of obesity than employed women’s husbands (OR = 0.69 (95% CI = 0.53–0.89. Men’s unemployment status was associated with wives’ greater odds of obesity (OR = 1.31 (95% CI = 1.01–1.71. HPA was associated with men’s employment status and income level, but not with women’s. The population representative survey showed that spousal resemblance in weight status and HPA varied with socioeconomic and demographic factors.

  14. 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 ...

  15. 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.

  16. 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...

  17. 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.

  18. 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

  19. Virtual reality technology and applications

    CERN Document Server

    Mihelj, Matjaž; Beguš, Samo

    2014-01-01

    As virtual reality expands from the imaginary worlds of science fiction and pervades every corner of everyday life, it is becoming increasingly important for students and professionals alike to understand the diverse aspects of this technology. This book aims to provide a comprehensive guide to the theoretical and practical elements of virtual reality, from the mathematical and technological foundations of virtual worlds to the human factors and the applications that enrich our lives: in the fields of medicine, entertainment, education and others. After providing a brief introduction to the topic, the book describes the kinematic and dynamic mathematical models of virtual worlds. It explores the many ways a computer can track and interpret human movement, then progresses through the modalities that make up a virtual world: visual, acoustic and haptic. It explores the interaction between the actual and virtual environments, as well as design principles of the latter. The book closes with an examination of diff...

  20. The ethnography of virtual reality

    Directory of Open Access Journals (Sweden)

    Gavrilović Ljiljana 1

    2004-01-01

    Full Text Available This paper discusses possible application of ethnographic research in the realm of virtual reality, especially in the relationship between cultures in virtual communities. This represents an entirely new area of ethnographic research and therefore many adjustments in the research design are needed for example, a development of a specific method of data gathering and tools for their verification. A virtual, cyber space is a version of social space more or less synchronous with it, but without the, "real", that is, physical presence of the people who create it. This virtual reality, defined and bounded by virtual space, is in fact real - and though we are not able to observe real, physical parameters of its existence, we can perceive its consequences. In sum, an innovative ethnographic research method is fully applicable for exploring the realm of virtual reality; in order to do so we need to expand, in addition to the new research design and methods, the field of science itself.

  1. Surgery applications of virtual reality

    Science.gov (United States)

    Rosen, Joseph

    1994-01-01

    Virtual reality is a computer-generated technology which allows information to be displayed in a simulated, bus lifelike, environment. In this simulated 'world', users can move and interact as if they were actually a part of that world. This new technology will be useful in many different fields, including the field of surgery. Virtual reality systems can be used to teach surgical anatomy, diagnose surgical problems, plan operations, simulate and perform surgical procedures (telesurgery), and predict the outcomes of surgery. The authors of this paper describe the basic components of a virtual reality surgical system. These components include: the virtual world, the virtual tools, the anatomical model, the software platform, the host computer, the interface, and the head-coupled display. In the chapter they also review the progress towards using virtual reality for surgical training, planning, telesurgery, and predicting outcomes. Finally, the authors present a training system being developed for the practice of new procedures in abdominal surgery.

  2. A Virtual Commissioning Learning Platform

    DEFF Research Database (Denmark)

    Mortensen, Steffen; Madsen, Ole

    2018-01-01

    Production Lab integrates a number of Industry 4.0 technologies for learning and research purposes. One of the many techniques is virtual commissioning. Virtual commissioning uses a virtual plant model and real controllers (PLCs) enabling a full emulation of the manufacturing system for verification. Virtual......The introduction of reconfigurable manufacturing systems (RMS), Industry 4.0 and the associated technologies requires the establishment of new competencies. Towards that goal, Aalborg University (AAU) has developed an Industry 4.0 learning factory, the AAU Smart Production Lab. The AAU Smart...... commissioning can lower the commissioning time up to 63%, allowing faster time to market. However, virtual commission is still missing industrial impact one of the reasons being lack of competencies and integration experiences. The paper presents the setup of the virtual commissioning learning platform...

  3. Virtual Reality for Anxiety Disorders

    Directory of Open Access Journals (Sweden)

    Elif Uzumcu

    2018-03-01

    Full Text Available Virtual reality is a relatively new exposure tool that uses three-dimensional computer-graphics-based technologies which allow the individual to feel as if they are physically inside the virtual environment by misleading their senses. As virtual reality studies have become popular in the field of clinical psychology in recent years, it has been observed that virtual-reality-based therapies have a wide range of application areas, especially on anxiety disorders. Studies indicate that virtual reality can be more realistic than mental imagery and can create a stronger feeling of ԰resenceԻ that it is a safer starting point compared to in vivo exposure; and that it can be applied in a more practical and controlled manner. The aim of this review is to investigate exposure studies based on virtual reality in anxiety disorders (specific phobias, panic disorder and agoraphobias, generalized anxiety disorder, social phobia, posttraumatic stress disorder and obsessive compulsive disorder.

  4. 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.

  5. 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...

  6. 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.

  7. 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...

  8. 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...

  9. 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....

  10. Virtual Vertical Aircraft Signal Training

    National Research Council Canada - National Science Library

    Norling, William

    1998-01-01

    .... Advances in virtual environments may provide a cost effective solution to the current live helicopter operations method of training, provided technical issues associated with hand and wand signal...

  11. Playful mediation and virtual sociality

    Directory of Open Access Journals (Sweden)

    Sihem NAJJAR

    2010-01-01

    Full Text Available As a space of sociability, virtual games, especially online role playing games, allow us to capture the interest of the playfulness in social life, but they are means by which users are able to experiment their relationship to others. The virtual games as a mediation device, constitute a "pretext" to forge friendships, develop love relationships, improve language skills, discover other cultures, etc. Based on a sociological survey of Tunisian Internet users (both sexes fans of virtual games we try to show how playful mediation is producing a multifaceted virtual sociality inherent in our contemporary societies.

  12. Virtual microscopy in pathology education.

    Science.gov (United States)

    Dee, Fred R

    2009-08-01

    Technology for acquisition of virtual slides was developed in 1985; however, it was not until the late 1990s that desktop computers had enough processing speed to commercialize virtual microscopy and apply the technology to education. By 2000, the progressive decrease in use of traditional microscopy in medical student education had set the stage for the entry of virtual microscopy into medical schools. Since that time, it has been successfully implemented into many pathology courses in the United States and around the world, with surveys indicating that about 50% of pathology courses already have or expect to implement virtual microscopy. Over the last decade, in addition to an increasing ability to emulate traditional microscopy, virtual microscopy has allowed educators to take advantage of the accessibility, efficiency, and pedagogic versatility of the computer and the Internet. The cost of virtual microscopy in education is now quite reasonable after taking into account replacement cost for microscopes, maintenance of glass slides, and the fact that 1-dimensional microscope space can be converted to multiuse computer laboratories or research. Although the current technology for implementation of virtual microscopy in histopathology education is very good, it could be further improved upon by better low-power screen resolution and depth of field. Nevertheless, virtual microscopy is beginning to play an increasing role in continuing education, house staff education, and evaluation of competency in histopathology. As Z-axis viewing (focusing) becomes more efficient, virtual microscopy will also become integrated into education in cytology, hematology, microbiology, and urinalysis.

  13. Virtual corporations, enterprise and organisation

    Directory of Open Access Journals (Sweden)

    Carmen RÃDUT

    2009-06-01

    Full Text Available Virtual organisation is a strategic paradigm that is centred on the use of information and ICT to create value. Virtual organisation is presented as a metamanagement strategy that has application in all value oriented organisations. Within the concept of Virtual organisation, the business model is an ICT based construct that bridges and integrates enterprise strategic and operational concerns. Firms try to ameliorate the impacts of risk and product complexity by forming alliances and partnerships with others to spread the risk of new products and new ventures and to increase organisational competence. The result is a networked virtual organization.

  14. 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).

  15. The Virtual Dressing Room

    DEFF Research Database (Denmark)

    Holte, Michael Boelstoft

    2013-01-01

    kinds: (1) virtual real-time 2D image/video techniques, where the consumer gets to superimpose the clothes on their real-time video to visualize themselves wearing the clothes. (2) 2D and 3D mannequins, where a web-application uses the body measurements provided by the customer, to superimpose...... the standard sizes to fit a customized 2D or 3D mannequin before buying. (3) 3D camera and laser technologies which acquire 3D information of the costumer, enabling estimation of the body shape and measurements. Additionally, we conduct user studies to investigate the user behavior when buying clothes...

  16. Analizar las interacciones virtuales

    Directory of Open Access Journals (Sweden)

    Luis Gómez Encinas

    2003-11-01

    Full Text Available El propósito de este artículo es abordar una serie de cuestiones relacionadas con las interacciones virtuales. En concreto, nos centraremos en el IRC, los comúnmente llamados chats, para a partir de una crítica a ciertos posicionamientos analíticos, expresar la necesidad de indagar en esa faceta del ciberespacio desde el punto de vista de las relaciones sociales. Nuevas relaciones sociales, que acontecen en un espacio nuevo, y que por tanto se desarrollan bajo reglas y motivaciones que desbordan los viejos esquemas de observación.

  17. Grids, Clouds and Virtualization

    CERN Document Server

    Cafaro, Massimo

    2011-01-01

    Research into grid computing has been driven by the need to solve large-scale, increasingly complex problems for scientific applications. Yet the applications of grid computing for business and casual users did not begin to emerge until the development of the concept of cloud computing, fueled by advances in virtualization techniques, coupled with the increased availability of ever-greater Internet bandwidth. The appeal of this new paradigm is mainly based on its simplicity, and the affordable price for seamless access to both computational and storage resources. This timely text/reference int

  18. Interactive virtual optical laboratories

    Science.gov (United States)

    Liu, Xuan; Yang, Yi

    2017-08-01

    Laboratory experiences are essential for optics education. However, college students have limited access to advanced optical equipment that is generally expensive and complicated. Hence there is a need for innovative solutions to expose students to advanced optics laboratories. Here we describe a novel approach, interactive virtual optical laboratory (IVOL) that allows unlimited number of students to participate the lab session remotely through internet, to improve laboratory education in photonics. Although students are not physically conducting the experiment, IVOL is designed to engage students, by actively involving students in the decision making process throughout the experiment.

  19. Mobile Virtual Private Networking

    Science.gov (United States)

    Pulkkis, Göran; Grahn, Kaj; Mårtens, Mathias; Mattsson, Jonny

    Mobile Virtual Private Networking (VPN) solutions based on the Internet Security Protocol (IPSec), Transport Layer Security/Secure Socket Layer (SSL/TLS), Secure Shell (SSH), 3G/GPRS cellular networks, Mobile IP, and the presently experimental Host Identity Protocol (HIP) are described, compared and evaluated. Mobile VPN solutions based on HIP are recommended for future networking because of superior processing efficiency and network capacity demand features. Mobile VPN implementation issues associated with the IP protocol versions IPv4 and IPv6 are also evaluated. Mobile VPN implementation experiences are presented and discussed.

  20. The Virtual Monte Carlo

    CERN Document Server

    Hrivnacova, I; Berejnov, V V; Brun, R; Carminati, F; Fassò, A; Futo, E; Gheata, A; Caballero, I G; Morsch, Andreas

    2003-01-01

    The concept of Virtual Monte Carlo (VMC) has been developed by the ALICE Software Project to allow different Monte Carlo simulation programs to run without changing the user code, such as the geometry definition, the detector response simulation or input and output formats. Recently, the VMC classes have been integrated into the ROOT framework, and the other relevant packages have been separated from the AliRoot framework and can be used individually by any other HEP project. The general concept of the VMC and its set of base classes provided in ROOT will be presented. Existing implementations for Geant3, Geant4 and FLUKA and simple examples of usage will be described.

  1. Curso virtual de epilepsia

    OpenAIRE

    García Orjuela, Jemmy Xiomara

    2011-01-01

    El curso virtual de epilepsia es una herramienta informática dirigida a los estudiantes de pregrado de medicina de la Universidad Nacional de Colombia de sexto y séptimo semestre, resultado de la experiencia de la Liga Central Contra la Epilepsia y el esfuerzo mancomunado de los docentes del Departamento de Medicina Interna con la Unidad de Neurología, sus residentes e internos, y su finalidad es facilitar el autoaprendizaje y complementar los conceptos en el área en mención. Siendo de acces...

  2. Virtual Black Holes

    OpenAIRE

    Hawking, Stephen W.

    1995-01-01

    One would expect spacetime to have a foam-like structure on the Planck scale with a very high topology. If spacetime is simply connected (which is assumed in this paper), the non-trivial homology occurs in dimension two, and spacetime can be regarded as being essentially the topological sum of $S^2\\times S^2$ and $K3$ bubbles. Comparison with the instantons for pair creation of black holes shows that the $S^2\\times S^2$ bubbles can be interpreted as closed loops of virtual black holes. It is ...

  3. Virtual Paint for Android

    OpenAIRE

    Miloeski, Aleksandar

    2017-01-01

    The aim of this thesis is to create a functional application for the Android environment that allows the user to do simple virtual drawings without the use of the touch screen, but rather through hand motions caught by the camera. There is a variety of approaches to this end, which vary by complexity and performance. This piece of work attempts to find a middle ground among the existing algorithms, as well as to build on and improve them specifically for this particular task. The idea is ...

  4. Virtual Reality in Neurorehabilitation

    Directory of Open Access Journals (Sweden)

    Stasieńko Agnieszka

    2016-12-01

    Full Text Available This article includes current information on the use of modern IT solutions and virtual-reality (VR-based technologies in medical rehabilitation. A review of current literature on VR-based interventions and their indications, benefits and limitations in patients with nervous system diseases was conducted. The popularity of VR-based training as a tool used for rehabilitation of patients with acute and chronic deficits in both sensory-motor and cognitive disorders is increasing. Still, there is a need for large randomized trials to evaluate the efficacy and safety of VR-based rehabilitation techniques in different disease entities. .

  5. Acute paretic syndrome in juvenile White Leghorn chickens resembles late stages of acute inflammatory demyelinating polyneuropathies in humans

    Directory of Open Access Journals (Sweden)

    Preisinger Rudolf

    2010-01-01

    Full Text Available Abstract Background Sudden limb paresis is a common problem in White Leghorn flocks, affecting about 1% of the chicken population before achievement of sexual maturity. Previously, a similar clinical syndrome has been reported as being caused by inflammatory demyelination of peripheral nerve fibres. Here, we investigated in detail the immunopathology of this paretic syndrome and its possible resemblance to human neuropathies. Methods Neurologically affected chickens and control animals from one single flock underwent clinical and neuropathological examination. Peripheral nervous system (PNS alterations were characterised using standard morphological techniques, including nerve fibre teasing and transmission electron microscopy. Infiltrating cells were phenotyped immunohistologically and quantified by flow cytometry. The cytokine expression pattern was assessed by quantitative real-time PCR (qRT-PCR. These investigations were accomplished by MHC genotyping and a PCR screen for Marek's disease virus (MDV. Results Spontaneous paresis of White Leghorns is caused by cell-mediated, inflammatory demyelination affecting multiple cranial and spinal nerves and nerve roots with a proximodistal tapering. Clinical manifestation coincides with the employment of humoral immune mechanisms, enrolling plasma cell recruitment, deposition of myelin-bound IgG and antibody-dependent macrophageal myelin-stripping. Disease development was significantly linked to a 539 bp microsatellite in MHC locus LEI0258. An aetiological role for MDV was excluded. Conclusions The paretic phase of avian inflammatory demyelinating polyradiculoneuritis immunobiologically resembles the late-acute disease stages of human acute inflammatory demyelinating polyneuropathy, and is characterised by a Th1-to-Th2 shift.

  6. 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

  7. On virtual displacement and virtual work in Lagrangian dynamics

    International Nuclear Information System (INIS)

    Ray, Subhankar; Shamanna, J

    2006-01-01

    The confusion and ambiguity encountered by students in understanding virtual displacement and virtual work is discussed in this paper. A definition of virtual displacement is presented that allows one to express them explicitly for holonomic (velocity independent), non-holonomic (velocity dependent), scleronomous (time independent) and rheonomous (time dependent) constraints. It is observed that for holonomic, scleronomous constraints, the virtual displacements are the displacements allowed by the constraints. However, this is not so for a general class of constraints. For simple physical systems, it is shown that the work done by the constraint forces on virtual displacements is zero. This motivates Lagrange's extension of d'Alembert's principle to a system of particles in constrained motion. However, a similar zero work principle does not hold for the allowed displacements. It is also demonstrated that d'Alembert's principle of zero virtual work is necessary for the solvability of a constrained mechanical problem. We identify this special class of constraints, physically realized and solvable, as the ideal constraints. The concept of virtual displacement and the principle of zero virtual work by constraint forces are central to both Lagrange's method of undetermined multipliers and Lagrange's equations in generalized coordinates

  8. THE USE OF VIRTUAL ETHNOGRAPHY THE USE OF VIRTUAL ETHNOGRAPHY

    Directory of Open Access Journals (Sweden)

    Kadriye UZUN

    2012-04-01

    Full Text Available 3D virtual worlds can and have been used as a meeting place for distance education courses. Virtual worlds allow for group learning of the kind enjoyed by students gathered in a virtual classroom, where they know they are in a communal space, they are aware of the social process of learning and are affected by the presence and behaviour of their fellow students and tutor.Traditional ethnography has been adjusted to virtual environments and much research on this issue has been carried out under the umbrella of virtual ethnography. The increase in diverse Internet applications can be pointed out as the cause of this inclination and increase.In this study, the authors explain the method of virtual ethnography in detail, inform about data gathering instruments such as participatory virtual observation, online and offline (face to face interviews touch upon ethical questions related to field studies and highlight the elements that call for attention in the use of virtual ethnography in distance education studies.

  9. 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

  10. 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

  11. Durable PROX catalyst based on gold nanoparticles and hydrophobic silica

    KAUST Repository

    Laveille, Paco

    2016-01-20

    3 nm gold nanoparticles (Au NP) obtained by direct chemical reduction of AuPPh3Cl in the presence of methyl-terminated silica exhibit superior durability for low temperature CO oxidation in the presence of hydrogen (PROX). The activity of hydrophobic Au/SiO2-R972 indeed appears much more stable with time-on-stream than those of the OH-terminated, hydrophilic Au/TiO2 and Au/Al2O3 catalysts, with similar Au NP size. This enhanced stability is attributed to the peculiar catalyst surface of Au/SiO2-R972. Not only may the support hydrophobicity concentrate and facilitate reactant adsorption and product desorption over Au NP, but methyl-terminated SiO2-R972 likely also inhibits carbonatation of the Au/support interface. Hence, at a temperature at which H2/H2O “cleaning” of the carbonate-contaminated Au/Al2O3 and Au/TiO2 surface is inefficient (< 100°C), passivated Au/SiO2-R972 displays much more stable PROX activity. Besides, the virtual absence of surface hydroxyl groups, which provide sites for water formation in H2/O2 atmospheres, can also account for the improved PROX selectivity (>85%) observed over Au/SiO2-R972. This new example, of CO oxidation activity of gold nanoparticles dispersed over a hydrophobic, “inert” support, clearly emphasizes the role of hydrogen as a promoter for the gold-catalyzed oxidation of CO at low temperature. Unlike support-mediated oxygen activation, hydrogen-only mediated oxygen activation takes full advantage of the hydrophobic surface, which is much more resistant against CO2 and thus remains free of poisonous carbonate species, as compared with hydroxyl-terminated catalysts. Hence, although the absence of surface hydroxyl groups prevents the hydrophobic Au/SiO2-R972 catalyst to reach the state-of-the-art activities initially displayed by Au/TiO2 and Au/Al2O3, it brings long-term stability with time-on-stream and superior selectivity, which opens up promising perspectives in the development of viable PROX catalysts based on gold.

  12. Realidad Virtual: Potencial Educativo

    Directory of Open Access Journals (Sweden)

    Luz Santamaría Granados

    2013-08-01

    Full Text Available El grupo GIBRANT centró sus esfuerzos en la investigación de realidad virtual, al experimentar en el uso de herramientas del consorcio Web3D (VRML y X3D, para el diseño y modelamiento de mundos virtuales en 3D, así pudo evidenciar el trabajo de estudiantes y docentes en el proyecto USTA en 3D; como tambien en algunas prácticas de formación en colegios de educación media, que involucran el uso de TIC, en el desarrollo de competencias de ubicación espacial, trigonométrica y rotación de objetos; y la construcción de escenaios que afianzan el proceso de enseñanza - aprendizaje en cuanquier área del saber. Este articulo quiere hacer ver la facilidad y la potencialidad de las MTIC e invita a la comunidad de educacion básica y media a apropiarse de estas tecnologías para su propio beneficio.

  13. Grids, Clouds, and Virtualization

    Science.gov (United States)

    Cafaro, Massimo; Aloisio, Giovanni

    This chapter introduces and puts in context Grids, Clouds, and Virtualization. Grids promised to deliver computing power on demand. However, despite a decade of active research, no viable commercial grid computing provider has emerged. On the other hand, it is widely believed - especially in the Business World - that HPC will eventually become a commodity. Just as some commercial consumers of electricity have mission requirements that necessitate they generate their own power, some consumers of computational resources will continue to need to provision their own supercomputers. Clouds are a recent business-oriented development with the potential to render this eventually as rare as organizations that generate their own electricity today, even among institutions who currently consider themselves the unassailable elite of the HPC business. Finally, Virtualization is one of the key technologies enabling many different Clouds. We begin with a brief history in order to put them in context, and recall the basic principles and concepts underlying and clearly differentiating them. A thorough overview and survey of existing technologies provides the basis to delve into details as the reader progresses through the book.

  14. Virtual reality via photogrammetry

    Science.gov (United States)

    Zahrt, John D.; Papcun, George; Childers, Randy A.; Rubin, Naama

    1996-03-01

    We wish to walk into a photograph just as Alice walked into the looking glass. From a mathematical perspective, this problem is exceedingly ill-posed (e.g. Is that a large, distant object or a small, nearby object?). A human expert can supply a large amount of a priori information that can function as mathematical constraints. The constrained problem can then be attacked with photogrammetry to obtain a great deal of quantitative information which is otherwise only qualitatively apparent. The user determines whether the object to be analyzed contains two or three vanishing points, then selects an appropriate number of points from the photon to enable the code to compute the locations of the vanishing points. Using this information and the standard photogrammetric geometric algorithms, the location of the camera, relative to the structure, is determined. The user must also enter information regarding an absolute sense of scale. As the vectors from the camera to the various points chosen from the photograph are determined, the vector components (coordinates) are handed to a virtual reality software package. Once the objects are entered, the appropriate surfaces of the 3D object are `wallpapered' with the surface from the photograph. The user is then able to move through the virtual scene. A video will demonstrate our work.

  15. 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...

  16. 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 ...

  17. 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....

  18. 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

  19. 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.

  20. 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.

  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. 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

  3. 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...

  4. 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.

  5. Virtual Realities and the Future of Text.

    Science.gov (United States)

    Marcus, Stephen

    1992-01-01

    Discusses issues surrounding virtual reality and "virtual books." Suggests that those who are exploring the territory of virtual realities are already helping to expand and enrich expectations and visions for integrating technology into reading and writing. (RS)

  6. Training Spatial Knowledge Acquisition Using Virtual Environments

    National Research Council Canada - National Science Library

    Koh, Glenn

    1997-01-01

    .... Subjects were trained to recognize key features of a venue using one of: an immersive virtual environment, a nonimmersive virtual environment, an exocentric virtual model of the venue, and a walkthrough of the actual venue...

  7. Virtual Stationary Automata for Mobile Networks

    National Research Council Canada - National Science Library

    Dolev, Shlomi; Gilbert, Seth; Lahiani, Limor; Lynch, Nancy; Nolte, Tina

    2005-01-01

    We define a programming abstraction for mobile networks called the Virtual Stationary Automata programming layer, consisting of real mobile clients, virtual timed I/O automata called virtual stationary automata (VSAs...

  8. 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

  9. The metaphors of virtual worlds

    DEFF Research Database (Denmark)

    Reinhard, CarrieLynn D.

    The analysis of recollections of experiencing two types of virtual worlds where the recollections were in the form of metaphors.......The analysis of recollections of experiencing two types of virtual worlds where the recollections were in the form of metaphors....

  10. Realistic Visualization of Virtual Views

    DEFF Research Database (Denmark)

    Livatino, Salvatore

    2005-01-01

    phenomena captured in the reference photographs, (i.e. the transfer of photographic-realism). An overview of most prominent approaches in realistic virtual view synthesis will be presented and briefly discussed. Applications of proposed methods to visual survey, virtual cinematography, as well as mobile...

  11. Virtual Enterprise: Transforming Entrepreneurship Education

    Science.gov (United States)

    Borgese, Anthony

    2011-01-01

    Entrepreneurship education is ripe for utilizing experiential learning methods. Experiential methods are best learned when there is constant immersion into the subject matter. One such transformative learning methodology is Virtual Enterprise (VE). Virtual Enterprise is a multi-faceted, experiential learning methodology disseminated by the City…

  12. Virtuality and Reality in Science

    International Nuclear Information System (INIS)

    Cohen-Tannoudji, G.

    1995-01-01

    This book compiles eight contributions devoted to the topical question about the relation between virtuality and reality. In the theoretical frame of quantum and relativistic particle physics, the concept of virtuality is used according to its strict and precise meaning. In this context, particles are generally invented before their discovery. Some famous historical experiments which led to the postulation and then the discovery of new particles are mentioned. These examples are used to illustrate and to discuss the concept of virtuality as well as the physical reality of virtual processes. But, how can the concept of virtuality in other scientific fields be applied ? In order to answer this question, the concepts of virtuality and reality are discussed in other branches of physics as well as in other fields such as geophysics, cosmology and biology. Philosophical and sociological implications of virtual realities are also considered. Moreover, in relation to virtuality and reality, the connections between modeling, simulation and experimentation, their respective roles, the advantages and risks of their use are discussed (in relation to nuclear sciences and geophysical problems) (N.T.)

  13. Virtual Reality and Special Needs

    Science.gov (United States)

    Jeffs, Tara L.

    2009-01-01

    The use of virtual environments for special needs is as diverse as the field of Special Education itself and the individuals it serves. Individuals with special needs often face challenges with attention, language, spatial abilities, memory, higher reasoning and knowledge acquisition. Research in the use of Virtual Learning Environments (VLE)…

  14. Virtual Reality, Combat, and Communication.

    Science.gov (United States)

    Thrush, Emily Austin; Bodary, Michael

    2000-01-01

    Presents a brief examination of the evolution of virtual reality devices that illustrates how the development of this new medium is influenced by emerging technologies and by marketing pressures. Notes that understanding these influences may help prepare for the role of technical communicators in building virtual reality applications for education…

  15. Learning Experience with Virtual Worlds

    Science.gov (United States)

    Wagner, Christian

    2008-01-01

    Virtual worlds create a new opportunity to enrich the educational experience through media-rich immersive learning. Virtual worlds have gained notoriety in games such as World of Warcraft (WoW), which has become the most successful online game ever, and in "general purpose" worlds, such as Second Life (SL), whose participation levels (more than 10…

  16. Developing Trust in Virtual Teams

    Science.gov (United States)

    Germain, Marie-Line

    2011-01-01

    Rapid globalization, advances in technology, flatter organizational structures, synergistic cooperation among firms, and a shift to knowledge work environments have led to the increasing use of virtual teams in organizations. Selecting, training, and socializing employees in virtual teamwork has therefore become an important human resource…

  17. Virtual visualization of La Quintilla

    Directory of Open Access Journals (Sweden)

    Mariano Flores Gutiérrez

    2013-11-01

    Full Text Available In this article we give an overview of the production process of the virtual reconstrucción virtual archeology. While Referring to the Roman town of Lorca Limerick show the proper steps virtualizatión purchase.

  18. Virtual Technologies Trends in Education

    Science.gov (United States)

    Martín-Gutiérrez, Jorge; Mora, Carlos Efrén; Añorbe-Díaz, Beatriz; González-Marrero, Antonio

    2017-01-01

    Virtual reality captures people's attention. This technology has been applied in many sectors such as medicine, industry, education, video games, or tourism. Perhaps its biggest area of interest has been leisure and entertainment. Regardless the sector, the introduction of virtual or augmented reality had several constraints: it was expensive, it…

  19. 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.

  20. 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....

  1. 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.

  2. 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

  3. 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.

  4. Medical Procedural Training in Virtual Reality

    OpenAIRE

    Gåsbakk, Tarald; Snarby, Håvard

    2017-01-01

    Virtual reality tools have seen a large increase in interest over the last few years. Educators have been early adopters of such tools, and research have shown that students enjoy training in a virtual world using virtual reality devices. New tools for interacting with the virtual world, like the controllers offered by virtual reality products like HTC Vive and Oculus Rift opens for more immersive applications. In addition, the usage of real world medical imaging in virtual applications is a ...

  5. Designing and Embedding Reliable Virtual Infrastructures

    OpenAIRE

    Yeow, Wai-Leong; Westphal, Cédric; Kozat, Ulaş C.

    2010-01-01

    In a virtualized infrastructure where physical resources are shared, a single physical server failure will terminate several virtual servers and crippling the virtual infrastructures which contained those virtual servers. In the worst case, more failures may cascade from overloading the remaining servers. To guarantee some level of reliability, each virtual infrastructure, at instantiation, should be augmented with backup virtual nodes and links that have sufficient capacities. This ensures t...

  6. Guinea-pig interpubic joint (symphysis pubica relaxation at parturition: Underlying cellular processes that resemble an inflammatory response

    Directory of Open Access Journals (Sweden)

    Muñoz-de-Toro Mónica

    2003-11-01

    Full Text Available Abstract Background At term, cervical ripening in coordination with uterine contractions becomes a prerequisite for a normal vaginal delivery. Currently, cervical ripening is considered to occur independently from uterine contractions. Many evidences suggest that cervical ripening resembles an inflammatory process. Comparatively little attention has been paid to the increased flexibility of the pelvic symphysis that occurs in many species to enable safe delivery. The aim of this study was to investigate whether the guinea-pig interpubic joint relaxation process observed during late pregnancy and parturition resembles an inflammatory process. Methods Samples of pubic symphysis were taken from pregnant guinea-pigs sacrificed along gestation, parturition and postpartum. Serial sections of paraffin-embedded tissues were used to measure the interpubic distance on digitalized images, stained with Giemsa to quantify leukocyte infiltration and to describe the vascular area changes, or studied by the picrosirius-polarization method to evaluate collagen remodeling. P4 and E2 serum levels were measured by a sequential immunometric assay. Results Data showed that the pubic relaxation is associated with an increase in collagen remodeling. In addition, a positive correlation between E2 serum levels and the increase in the interpubic distance was found. On the other hand, a leukocyte infiltration in the interpubic tissue around parturition was described, with the presence of almost all inflammatory cells types. At the same time, histological images show an increase in vascular area (angiogenesis. Eosinophils reached their highest level immediately before parturition; whereas for the neutrophilic and mononuclear infiltration higher values were recorded one day after parturition. Correlation analysis showed that eosinophils and mononuclear cells were positively correlated with E2 levels, but only eosinophilic infiltration was associated with collagen remodeling

  7. Virtual detector theory for strong-field atomic ionization

    Science.gov (United States)

    Wang, Xu; Tian, Justin; Eberly, J. H.

    2018-04-01

    A virtual detector (VD) is an imaginary device located at a fixed position in space that extracts information from the wave packet passing through it. By recording the particle momentum and the corresponding probability current at each time, the VDs can accumulate and build the differential momentum distribution of the particle, in a way that resembles real experiments. A mathematical proof is given for the equivalence of the differential momentum distribution obtained by the VD method and by Fourier transforming the wave function. In addition to being a tool for reducing the computational load, VDs have also been found useful in interpreting the ultrafast strong-field ionization process, especially the controversial quantum tunneling process.

  8. Visual Realism and Presence in a Virtual Reality Game

    DEFF Research Database (Denmark)

    Hvass, Jonatan Salling; Larsen, Oliver Stevns; Vendelbo, Kasper Bøgelund

    2017-01-01

    Virtual Reality (VR) has finally entered the homes of consumers, and a large number of the available applications are games. This paper presents a between-subjects study (n=50) exploring if vi-sual realism (polygon count and texture resolution) affects pres-ence during a scenario involving gameplay......, graphics, and controls that, contrary to much existing research, resemble commercially available VR games. The results suggest that participants exposed to a higher degree of visual realism experienced a stronger sensa-tion of presence, as assessed by means of self-reports, and phys-iological measures...... revealed that higher visual realism also was accompanied by stronger fear responses which may be indicative of stronger presence....

  9. From alginate impressions to digital virtual models: accuracy and reproducibility.

    Science.gov (United States)

    Dalstra, Michel; Melsen, Birte

    2009-03-01

    To compare the accuracy and reproducibility of measurements performed on digital virtual models with those taken on plaster casts from models poured immediately after the impression was taken, the 'gold standard', and from plaster models poured following a 3-5 day shipping procedure of the alginate impression. Direct comparison of two measuring techniques. The study was conducted at the Department of Orthodontics, School of Dentistry, University of Aarhus, Denmark in 2006/2007. Twelve randomly selected orthodontic graduate students with informed consent. Three sets of alginate impressions were taken from the participants within 1 hour. Plaster models were poured immediately from two of the sets, while the third set was kept in transit in the mail for 3-5 days. Upon return a plaster model was poured as well. Finally digital models were made from the plaster models. A number of measurements were performed on the plaster casts with a digital calliper and on the corresponding digital models using the virtual measuring tool of the accompanying software. Afterwards these measurements were compared statistically. No statistical differences were found between the three sets of plaster models. The intra- and inter-observer variability are smaller for the measurements performed on the digital models. Sending alginate impressions by mail does not affect the quality and accuracy of plaster casts poured from them afterwards. Virtual measurements performed on digital models display less variability than the corresponding measurements performed with a calliper on the actual models.

  10. Diagnostic accuracy in virtual dermatopathology

    DEFF Research Database (Denmark)

    Mooney, E.; Kempf, W.; Jemec, G.B.E.

    2012-01-01

    Background Virtual microscopy is used for teaching medical students and residents and for in-training and certification examinations in the United States. However, no existing studies compare diagnostic accuracy using virtual slides and photomicrographs. The objective of this study was to compare...... diagnostic accuracy of dermatopathologists and pathologists using photomicrographs vs. digitized images, through a self-assessment examination, and to elucidate assessment of virtual dermatopathology. Methods Forty-five dermatopathologists and pathologists received a randomized combination of 15 virtual...... slides and photomicrographs with corresponding clinical photographs and information in a self-assessment examination format. Descriptive data analysis and comparison of groups were performed using a chi-square test. Results Diagnostic accuracy in dermatopathology using virtual dermatopathology...

  11. Modelling Virtual Environments for Geovisualization

    DEFF Research Database (Denmark)

    Bodum, Lars

    2005-01-01

    and use of virtual environments has developed form being a rather sophisticated type of visualization that demanded extreme computer resources to become an integral part of the software on every desktop computer. This chapter addresses both philosophical and technical issues regarding the modelling......The use of virtual environments in geovisualization has become a major topic within the last few years. The main reason for this interest in the growing use of 3D models and visual realizations in a wide range of applications concerned with the geographic element of information. The implementation...... of virtual environments. It specifically focuses on different representational aspects to be taken into consideration when a virtual environment is created. These aspects are data modelling, 3D modelling and level-of-detail. A range of different approaches can be taken to visualize a virtual environment...

  12. Marshall Engineers Use Virtual Reality

    Science.gov (United States)

    1993-01-01

    Virtual Reality (VR) can provide cost effective methods to design and evaluate components and systems for maintenance and refurbishment operations. Marshall Spce Flight Center (MSFC) is begirning to utilize VR for design analysis in the X-34 experimental reusable space vehicle. Analysts at MSFC's Computer Applications and Virtual Environments (CAVE) used Head Mounted Displays (HMD) (pictured), spatial trackers and gesture inputs as a means to animate or inhabit a properly sized virtual human model. These models are used in a VR scenario as a way to determine functionality of space and maintenance requirements for the virtual X-34. The primary functions of the virtual X-34 mockup is to support operations development and design analysis for engine removal, the engine compartment and the aft fuselage. This capability provides general visualization support to engineers and designers at MSFC and to the System Design Freeze Review at Orbital Sciences Corporation (OSC).

  13. Formal modeling of virtual machines

    Science.gov (United States)

    Cremers, A. B.; Hibbard, T. N.

    1978-01-01

    Systematic software design can be based on the development of a 'hierarchy of virtual machines', each representing a 'level of abstraction' of the design process. The reported investigation presents the concept of 'data space' as a formal model for virtual machines. The presented model of a data space combines the notions of data type and mathematical machine to express the close interaction between data and control structures which takes place in a virtual machine. One of the main objectives of the investigation is to show that control-independent data type implementation is only of limited usefulness as an isolated tool of program development, and that the representation of data is generally dictated by the control context of a virtual machine. As a second objective, a better understanding is to be developed of virtual machine state structures than was heretofore provided by the view of the state space as a Cartesian product.

  14. Virtual reality in surgical training.

    Science.gov (United States)

    Lange, T; Indelicato, D J; Rosen, J M

    2000-01-01

    Virtual reality in surgery and, more specifically, in surgical training, faces a number of challenges in the future. These challenges are building realistic models of the human body, creating interface tools to view, hear, touch, feel, and manipulate these human body models, and integrating virtual reality systems into medical education and treatment. A final system would encompass simulators specifically for surgery, performance machines, telemedicine, and telesurgery. Each of these areas will need significant improvement for virtual reality to impact medicine successfully in the next century. This article gives an overview of, and the challenges faced by, current systems in the fast-changing field of virtual reality technology, and provides a set of specific milestones for a truly realistic virtual human body.

  15. Family Resemblances: Human Reproductive Cloning as an Example for Reconsidering the Mutual Relationships between Bioethics and Science Fiction.

    Science.gov (United States)

    Hansen, Solveig L

    2018-03-08

    In the traditions of narrative ethics and casuistry, stories have a well-established role. Specifically, illness narratives provide insight into patients' perspectives and histories. However, because they tend to see fiction as an aesthetic endeavour, practitioners in these traditions often do not realize that fictional stories are valuable moral sources of their own. In this paper I employ two arguments to show the mutual relationship between bioethics and fiction, specifically, science fiction. First, both discourses use imagination to set a scene and determine a perspective. Second, bioethics and science fiction share the family resemblance of expressing moral beliefs. I then consider how understanding bioethics and science fiction as interrelated discourses can be the basis of a methodology for inquiry into relational autonomy in the context of biotechnologies and medicine. As an example of this methodology, I analyse Fay Weldon's novel The Cloning of Joanna May (1989).

  16. 'Hair-on-end' skull changes resembling thalassemia caused by marrow expansion in uncorrected complex cyanotic heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Walor, David M.; Berdon, Walter E. [Columbia University Medical Center, Department of Radiology Children' s Hospital of New York, New York, NY (United States); Westra, Sjirk J. [Massachusetts General Hospital, Department of Radiology, Boston, MA (United States)

    2005-07-01

    ''Hair-on-end'' skull changes resembling thalassemia were rarely described in the 1950s and 1960s in children with cyanotic congenital heart diseases; these changes were described almost entirely in patients with tetralogy of Fallot or D-transposition of the great arteries. As these lesions have become correctable, the osseous changes, never common, seem now only to exist in a small number of patients with uncorrectable complex cyanotic congenital heart disease who survive in a chronic hypoxic state. We present two cases: a case of marked marrow expansion in the skull of a 5-year-old boy with uncorrectable cyanotic heart disease studied by CT, and a second case of an 8-year-old with tetralogy of Fallot and pulmonary atresia studied by plain skull radiographs. The true incidence of these findings is unknown. (orig.)

  17. 'Hair-on-end' skull changes resembling thalassemia caused by marrow expansion in uncorrected complex cyanotic heart disease

    International Nuclear Information System (INIS)

    Walor, David M.; Berdon, Walter E.; Westra, Sjirk J.

    2005-01-01

    ''Hair-on-end'' skull changes resembling thalassemia were rarely described in the 1950s and 1960s in children with cyanotic congenital heart diseases; these changes were described almost entirely in patients with tetralogy of Fallot or D-transposition of the great arteries. As these lesions have become correctable, the osseous changes, never common, seem now only to exist in a small number of patients with uncorrectable complex cyanotic congenital heart disease who survive in a chronic hypoxic state. We present two cases: a case of marked marrow expansion in the skull of a 5-year-old boy with uncorrectable cyanotic heart disease studied by CT, and a second case of an 8-year-old with tetralogy of Fallot and pulmonary atresia studied by plain skull radiographs. The true incidence of these findings is unknown. (orig.)

  18. An analysis on equal width quantization and linearly separable subcode encoding-based discretization and its performance resemblances

    Directory of Open Access Journals (Sweden)

    Lim Meng-Hui

    2011-01-01

    Full Text Available Abstract Biometric discretization extracts a binary string from a set of real-valued features per user. This representative string can be used as a cryptographic key in many security applications upon error correction. Discretization performance should not degrade from the actual continuous features-based classification performance significantly. However, numerous discretization approaches based on ineffective encoding schemes have been put forward. Therefore, the correlation between such discretization and classification has never been made clear. In this article, we aim to bridge the gap between continuous and Hamming domains, and provide a revelation upon how discretization based on equal-width quantization and linearly separable subcode encoding could affect the classification performance in the Hamming domain. We further illustrate how such discretization can be applied in order to obtain a highly resembled classification performance under the general Lp distance and the inner product metrics. Finally, empirical studies conducted on two benchmark face datasets vindicate our analysis results.

  19. Lynch Syndrome Associated Colon Adenocarcinoma Resembling Lymphoma on Fluoro-Deoxyglucose-Positron Emission Tomography/Computed Tomography

    International Nuclear Information System (INIS)

    Aparici, Carina Mari; Win, Aung Zaw

    2015-01-01

    The patient was a 46-year-old Asian male diagnosed with lynch syndrome associated colon adenocarcinoma in the right ascending colon. A presurgical staging 18-fluoro-deoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) found increased metabolic activity in the cervical, axillary, mediastinal, supraclavicular, para-aortic and mesenteric lymph nodes. This pattern of metastasis was very unusual for lynch syndrome associated colon adenocarcinoma and the involvement of those lymph nodes resembles the pattern of spread of lymphoma. He underwent right hemicolectomy and he was subsequently treated with 12 cycles of folinic acid (leucovorin), fluorouracil (5-FU), irinotecan. A restaging FDG-PET/CT at the end of the chemotherapy showed interval decrease in size and metabolic activity in the affected lymph nodes. FDG-PET/CT is a useful imaging modality in following-up the treatment response in colon adenocarcinoma

  20. 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

  1. APLIKASI VIRTUAL TOUR 3D PABRIK PT. X

    Directory of Open Access Journals (Sweden)

    Willy Nugraha Utomo

    2014-01-01

    Full Text Available Company X is a reputable company that has more than 1000 people employees. One of the routines that performed by company X is orientation for new employees, and there is an event that invites them to visit the factory. The location of the main office and the factory is far, so this activity lacks time efficiency. This application aims to facilitate company X in conducting new employee orientation so that the location can be seen in the virtual world. The first thing in the process of making the application is visiting the factory to determine the shape and position of the object, so that the expected results are shown to resemble its original condition. 3d object and its texture are created using Blender application that can be imported into the made application. Collision feature aims to prevent users from penetrating the objects.The position, shape and location of objects contained in the application already resemble the original plant site. The main obstacle in making this application is the creation time, so the detailed map of the plant cannot be completed. The main building, the production building and the warehouse have been made, only small objects contained in the main building have not been contained.

  2. Meningiomas with conventional MRI findings resembling intraaxial tumors: can perfusion-weighted MRI be helpful in differentiation?

    Energy Technology Data Exchange (ETDEWEB)

    Hakyemez, Bahattin [Uludag University Medical School, Department of Radiology, Bursa (Turkey); Bursa State Hospital, Department of Radiology, Bursa (Turkey); Yildirim, Nalan; Erdogan, Cueneyt; Parlak, Mufit [Uludag University Medical School, Department of Radiology, Bursa (Turkey); Kocaeli, Hasan; Korfali, Ender [Uludag University Medical School, Department of Neurosurgery, Bursa (Turkey)

    2006-10-15

    To investigate the contribution of perfusion-weighted MRI to the differentiation of meningiomas with atypical conventional MRI findings from intraaxial tumors. We retrospectively analyzed 54 meningiomas, 12 glioblastomas and 13 solitary metastases. We detected 6 meningiomas with atypical features on conventional MRI resembling intraaxial tumors. The regional cerebral blood flow (rCBV) ratios of all tumors were calculated via perfusion-weighted MRI. The signal intensity-time curves were plotted and three different curve patterns were observed. The type 1 curve resembled normal brain parenchyma or the postenhancement part was minimally below the baseline, the type 2 curve was similar to the type 1 curve but with the postenhancement part above the baseline, and the type 3 curve had the postenhancement part below the baseline accompanied by widening of the curve. Student's t-test was used for statistical analysis. On CBV images meningiomas were hypervascular and the mean rCBV ratio was 10.58{+-}2.00. For glioblastomas and metastatic lesions, the rCBV ratios were 5.02{+-}1.40 and 4.68{+-}1.54, respectively. There was a statistically significant difference in rCBV ratios between meningiomas and glioblastomas and metastases (P<0.001). Only one of the meningiomas displayed a type 2 curve while five showed a type 3 curve. Glioblastomas and metastases displayed either a type 1 or a type 2 curve. None of the meningiomas showed a type 1 curve and none of the glioblastomas or metastases showed a type 3 curve. (orig.)

  3. Pathogenesis of Candida albicans infections in the alternative chorio-allantoic membrane chicken embryo model resembles systemic murine infections.

    Directory of Open Access Journals (Sweden)

    Ilse D Jacobsen

    Full Text Available Alternative models of microbial infections are increasingly used to screen virulence determinants of pathogens. In this study, we investigated the pathogenesis of Candida albicans and C. glabrata infections in chicken embryos infected via the chorio-allantoic membrane (CAM and analyzed the virulence of deletion mutants. The developing immune system of the host significantly influenced susceptibility: With increasing age, embryos became more resistant and mounted a more balanced immune response, characterized by lower induction of proinflammatory cytokines and increased transcription of regulatory cytokines, suggesting that immunopathology contributes to pathogenesis. While many aspects of the chicken embryo response resembled murine infections, we also observed significant differences: In contrast to systemic infections in mice, IL-10 had a beneficial effect in chicken embryos. IL-22 and IL-17A were only upregulated after the peak mortality in the chicken embryo model occurred; thus, the role of the Th17 response in this model remains unclear. Abscess formation occurs frequently in murine models, whereas the avian response was dominated by granuloma formation. Pathogenicity of the majority of 15 tested C. albicans deletion strains was comparable to the virulence in mouse models and reduced virulence was associated with significantly lower transcription of proinflammatory cytokines. However, fungal burden did not correlate with virulence and for few mutants like bcr1Δ and tec1Δ different outcomes in survival compared to murine infections were observed. C. albicans strains locked in the yeast stage disseminated significantly more often from the CAM into the embryo, supporting the hypothesis that the yeast morphology is responsible for dissemination in systemic infections. These data suggest that the pathogenesis of C. albicans infections in the chicken embryo model resembles systemic murine infections but also differs in some aspects. Despite

  4. Virtual reality cerebral aneurysm clipping simulation with real-time haptic feedback.

    Science.gov (United States)

    Alaraj, Ali; Luciano, Cristian J; Bailey, Daniel P; Elsenousi, Abdussalam; Roitberg, Ben Z; Bernardo, Antonio; Banerjee, P Pat; Charbel, Fady T

    2015-03-01

    With the decrease in the number of cerebral aneurysms treated surgically and the increase of complexity of those treated surgically, there is a need for simulation-based tools to teach future neurosurgeons the operative techniques of aneurysm clipping. To develop and evaluate the usefulness of a new haptic-based virtual reality simulator in the training of neurosurgical residents. A real-time sensory haptic feedback virtual reality aneurysm clipping simulator was developed using the ImmersiveTouch platform. A prototype middle cerebral artery aneurysm simulation was created from a computed tomographic angiogram. Aneurysm and vessel volume deformation and haptic feedback are provided in a 3-dimensional immersive virtual reality environment. Intraoperative aneurysm rupture was also simulated. Seventeen neurosurgery residents from 3 residency programs tested the simulator and provided feedback on its usefulness and resemblance to real aneurysm clipping surgery. Residents thought that the simulation would be useful in preparing for real-life surgery. About two-thirds of the residents thought that the 3-dimensional immersive anatomic details provided a close resemblance to real operative anatomy and accurate guidance for deciding surgical approaches. They thought the simulation was useful for preoperative surgical rehearsal and neurosurgical training. A third of the residents thought that the technology in its current form provided realistic haptic feedback for aneurysm surgery. Neurosurgical residents thought that the novel immersive VR simulator is helpful in their training, especially because they do not get a chance to perform aneurysm clippings until late in their residency programs.

  5. Augmented Virtual Reality Laboratory

    Science.gov (United States)

    Tully-Hanson, Benjamin

    2015-01-01

    Real time motion tracking hardware has for the most part been cost prohibitive for research to regularly take place until recently. With the release of the Microsoft Kinect in November 2010, researchers now have access to a device that for a few hundred dollars is capable of providing redgreenblue (RGB), depth, and skeleton data. It is also capable of tracking multiple people in real time. For its original intended purposes, i.e. gaming, being used with the Xbox 360 and eventually Xbox One, it performs quite well. However, researchers soon found that although the sensor is versatile, it has limitations in real world applications. I was brought aboard this summer by William Little in the Augmented Virtual Reality (AVR) Lab at Kennedy Space Center to find solutions to these limitations.

  6. VIRTUAL REALITY HYPNOSIS.

    Science.gov (United States)

    Askay, Shelley Wiechman; Patterson, David R; Sharar, Sam R

    2009-03-01

    Scientific evidence for the viability of hypnosis as a treatment for pain has flourished over the past two decades (Rainville, Duncan, Price, Carrier and Bushnell, 1997; Montgomery, DuHamel and Redd, 2000; Lang and Rosen, 2002; Patterson and Jensen, 2003). However its widespread use has been limited by factors such as the advanced expertise, time and effort required by clinicians to provide hypnosis, and the cognitive effort required by patients to engage in hypnosis.The theory in developing virtual reality hypnosis was to apply three-dimensional, immersive, virtual reality technology to guide the patient through the same steps used when hypnosis is induced through an interpersonal process. Virtual reality replaces many of the stimuli that the patients have to struggle to imagine via verbal cueing from the therapist. The purpose of this paper is to explore how virtual reality may be useful in delivering hypnosis, and to summarize the scientific literature to date. We will also explore various theoretical and methodological issues that can guide future research.In spite of the encouraging scientific and clinical findings, hypnosis for analgesia is not universally used in medical centres. One reason for the slow acceptance is the extensive provider training required in order for hypnosis to be an effective pain management modality. Training in hypnosis is not commonly offered in medical schools or even psychology graduate curricula. Another reason is that hypnosis requires far more time and effort to administer than an analgesic pill or injection. Hypnosis requires training, skill and patience to deliver in medical centres that are often fast-paced and highly demanding of clinician time. Finally, the attention and cognitive effort required for hypnosis may be more than patients in an acute care setting, who may be under the influence of opiates and benzodiazepines, are able to impart. It is a challenge to make hypnosis a standard part of care in this environment

  7. Virtual Meteorological Center

    Directory of Open Access Journals (Sweden)

    Marius Brinzila

    2007-10-01

    Full Text Available A virtual meteorological center, computer based with Internet possibility transmission of the information is presented. Circumstance data is collected with logging field meteorological station. The station collects and automatically save data about the temperature in the air, relative humidity, pressure, wind speed and wind direction, rain gauge, solar radiation and air quality. Also can perform sensors test, analyze historical data and evaluate statistical information. The novelty of the system is that it can publish data over the Internet using LabVIEW Web Server capabilities and deliver a video signal to the School TV network. Also the system performs redundant measurement of temperature and humidity and was improved using new sensors and an original signal conditioning module.

  8. 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)

  9. 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.

  10. STUDY ON VIRTUAL COLONOSCOPY

    Directory of Open Access Journals (Sweden)

    Aithagani Rama Chandraiah

    2016-10-01

    Full Text Available BACKGROUND Current options available in the investigations of colorectal carcinoma include screening using digital rectal examination, sigmoidoscopy, barium enema and fiberoptic colonoscopy, virtual colonoscopy. The aim of the study was to prospectively evaluate patient acceptance of virtual colonoscopy compared with that of conventional colonoscopy when performed in patients with or suspected of having colorectal disease. MATERIALS AND METHODS The study had been conducted on patients attending Department of Radiology for a period of 1 year. Patients with primary or secondary complaints of pain abdomen, lump in abdomen, bleeding per rectum, loose motions/constipation, altered bowel habits, loss of appetite and weight and anaemia, so total number of cases were 51. RESULTS In our study, the patients were in age groups of 21-70 years. Both sexes were represented in our study. Male preponderance was noted in 51 patients. Cases of adenoma were more commonly found 37 (72.78%. The sensitivity of the CT colonography for the polyps more than 10 mm is 100%, polyps 6-9 mm is 90%, less than 6 mm is 80%. Our study consists of 51 patients; among them, 30 patients showed acceptance for CT colonography, 10 patients for optical colonoscopy. Our study consists of 51 patients, the polyps (more than 10 mm detected in 2D viewing were 24, 2D and 3D viewing of 24, the polyps (less than 10 mm detected in 2D viewing were 15, 2D and 3D viewing were 17. 3D viewing resulted in increased sensitivity for identification of patients with larger polyps more than 1 cm, (70-85% sensitivity and patients with smaller polyps less than 1 cm (increased sensitivity 75-88%. CONCLUSIONS Multislice CT (64 colonography is a good alternative to other colorectal screening tests because it has high sensitivity for polyps 10 mm or more in diameter is relatively safe, clinical effective, minimally invasive, cost effective and filter for therapeutic optical colonoscopy.

  11. Virtual reality and anthropology

    International Nuclear Information System (INIS)

    Recheis, Wolfgang; Weber, Gerhard W.; Schaefer, Katrin; Knapp, Rudolf; Seidler, Horst; Zur Nedden, Dieter

    1999-01-01

    Since the discovery of the Tyrolean Iceman in 1991 advanced imaging and post processing techniques were successfully applied in anthropology. Specific techniques include spiral computed tomography and 3-dimensional reconstructions including stereolithographic and fused deposition modeling of volume data sets. The Iceman's skull was the first to be reproduced using stereolithography, before this method was successfully applied in preoperative planning. With the advent of high-end graphics workstations and biomedical image processing software packages, 3-dimensional reconstructions were established as a routine tool for analyzing volume data sets. These techniques opened totally new insights in the field of physical anthropology. Computed tomography became the ideal research tool to access the internal structures of various precious fossils without damaging or even touching them. Many of the most precious specimens from the species Autralopithecus (1.8-3.5 Myears), Homo heidelbergensis (200-600 kyears) or Homo neanderthalensis (40-100 kyears) were scanned during the last 5 years. Often the fossils are filled with a stone matrix or other materials. During the postprocessing routines highly advanced algorithms were used to remove virtually these incrustations. Thus it was possible to visualize the morphological structures that lie beneath the matrix. Some specimens were partially destroyed, so the missing parts were reconstructed on computer screen in order to get estimations of the brain volume and endocranial morphology, both major fields of interest in physical anthropology. Moreover the computerized form of the data allows new descriptions of morphologic structures by the means of 'geometric morphometrics'. Some of the results may change aspects and interpretations in human evolution. The introduction of new imaging and post processing techniques created a new field of research: Virtual Anthropology

  12. Geomatics and virtual tourism

    Directory of Open Access Journals (Sweden)

    Valeria Minucciani

    2013-09-01

    Full Text Available The most recent technological revolution, concerning web and “ICT”, not only changed individual and collective behaviors, but also allowed experiences no possible before: a real time communication, regardless of the distances; an extended access to disjointed data and sources; the shift in different realities – missing or entirely imaginary. Nowadays, we can think about a new concept of museum, much more inclusive than “objects container”: now the museum involves entire countries, entire ecosystems, entire regions. We can speak of “museum outside of the museum”, to extend museum “storytelling” to a regional scale, beyond the walls of the traditional museum. On a regional scale experiments entirely convincing have not yet been carried out, but from this point of view cultural lands can be visited as great open air museums, to find objects, artworks or signs: the whole land is a “collection” to be preserved, to be presented and to be interpreted. Thus the visit allows to elicit outstanding objects, to read into landscapes with different filters. Both the physical and virtual visit seem to be a “tour” (Minucciani and Garnero, 2013. To create a virtual tourism prototypal station, we need several and unconventional geometrical data (shared geographic databases, DTMs, digital orthoimages and angle shots, modeling with spherical cameras, ..., thematic data (related to cultural content and no conventional input units to move and to observe how and where the observer prefers. Authors report here their experience to carry out a prototypal station, able to relate geomatics references to cultural content and to offer a whole experience, involving users also from the sensory point of view. That’s nowadays a specific purpose of new technologies applied to cultural heritage.

  13. Tracking Virtual Trajectories

    Science.gov (United States)

    Stone, Leland S.; Beutter, Brent R.; Lorenceau, Jean D.; Null, Cynthia H. (Technical Monitor)

    1996-01-01

    Current models of smooth pursuit eye movements assume that it is largely driven by retinal image motion. We tested this hypothesis by measuring pursuit of elliptical motion (3.2s, 0.9 Hz, 1.4 deg x 1.6 deg, 4 randomly interleaved phases) of either a small spot ("real" motion) or of a line-figure diamond viewed through apertures such that only the motion of four isolated oblique line segments was visible ("virtual" motion). Each segment moved sinusoidally along a linear trajectory yet subjects perceived a diamond moving along an elliptical path behind the aperture. We found, as expected, that real motion produced accurate tracking (N = 2) with mean gain (over horizontal and vertical) of 0.9, mean phase of -6 deg (lag), mean relative phase (H vs V) of 90 +/- 8 deg (RMS error). Virtual motion behind an X-shaped aperture (N= 4 with one naive) yielded a mean gain of 0.7, mean phase of -11 deg, mean relative phase of 87 +/- 15 deg. We also measured pursuit with the X-shaped aperture using a higher segment luminance which prevents the segments from being grouped into a coherently moving diamond while keeping the motion otherwise identical. In this incoherent case, the same four subjects no longer showed consistent elliptical tracking (RMS error in relative phase rose to 60 deg) suggesting that perceptual coherence is critical. Furthermore, to rule out tracking of the centroid, we also used vertical apertures so that all segment motion was vertical (N = 3). This stimulus still produced elliptical tracking (mean relative phase of 84 +/- 19 deg), albeit with a lower gain (0.6). These data show that humans can track moving objects reasonably accurately even when the trajectory can only be derived by spatial integration of motion signals. Models that merely seek to minimize retinal or local stimulus motion cannot explain these results.

  14. The Virtual Tablet: Virtual Reality as a Control System

    Science.gov (United States)

    Chronister, Andrew

    2016-01-01

    In the field of human-computer interaction, Augmented Reality (AR) and Virtual Reality (VR) have been rapidly growing areas of interest and concerted development effort thanks to both private and public research. At NASA, a number of groups have explored the possibilities afforded by AR and VR technology, among which is the IT Advanced Concepts Lab (ITACL). Within ITACL, the AVR (Augmented/Virtual Reality) Lab focuses on VR technology specifically for its use in command and control. Previous work in the AVR lab includes the Natural User Interface (NUI) project and the Virtual Control Panel (VCP) project, which created virtual three-dimensional interfaces that users could interact with while wearing a VR headset thanks to body- and hand-tracking technology. The Virtual Tablet (VT) project attempts to improve on these previous efforts by incorporating a physical surrogate which is mirrored in the virtual environment, mitigating issues with difficulty of visually determining the interface location and lack of tactile feedback discovered in the development of previous efforts. The physical surrogate takes the form of a handheld sheet of acrylic glass with several infrared-range reflective markers and a sensor package attached. Using the sensor package to track orientation and a motion-capture system to track the marker positions, a model of the surrogate is placed in the virtual environment at a position which corresponds with the real-world location relative to the user's VR Head Mounted Display (HMD). A set of control mechanisms is then projected onto the surface of the surrogate such that to the user, immersed in VR, the control interface appears to be attached to the object they are holding. The VT project was taken from an early stage where the sensor package, motion-capture system, and physical surrogate had been constructed or tested individually but not yet combined or incorporated into the virtual environment. My contribution was to combine the pieces of

  15. 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.

  16. A Framework for Virtual Hand Haptic Interaction

    Science.gov (United States)

    Han, Xiaoxia; Wan, Huagen

    Virtual hand interactions play key roles in virtual environments. The recent addition of force feedback to virtual reality simulations has enhanced their realism, especially when dexterous manipulation of virtual objects is concerned. However, though there exist many works on virtual hand modeling regarding computer animation and interaction applications, much less attention is paid on haptic modeling of virtual hand. In this paper, we propose a framework for virtual hand haptic interaction. The modeling of a sophisticated virtual hand for haptic interactions is investigated with special attention paid on issues of visual realism, motion realism as well as force sensation. Specifically, our virtual hand model simulates natural anatomy in its appearance, motion and deformation, and reflects the feature of force feedback datagloves. Besides, virtual hand interactions based on the constructed virtual hand model are discussed. The proposed framework has been tested on a PC with a force feedback dataglove.

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. NUCLEATION STUDIES OF GOLD ON CARBON ELECTRODES

    Directory of Open Access Journals (Sweden)

    S. SOBRI

    2008-04-01

    Full Text Available Interest has grown in developing non-toxic electrolytes for gold electrodeposition to replace the conventional cyanide-based bath for long term sustainability of gold electroplating. A solution containing thiosulphate and sulphite has been developed specially for microelectronics applications. However, at the end of the electrodeposition process, the spent electrolyte can contain a significant amount of gold in solution. This study has been initiated to investigate the feasibility of gold recovery from a spent thiosulphate-sulphite electrolyte. We have used flat-plate glassy carbon and graphite electrodes to study the mechanism of nucleation and crystal growth of gold deposition from the spent electrolyte. It was found that at the early stages of reduction process, the deposition of gold on glassy carbon exhibits an instantaneous nucleation of non-overlapping particles. At longer times, the particles begin to overlap and the deposition follows a classic progressive nucleation phenomenon. On the other hand, deposition of gold on graphite does not follow the classical nucleation phenomena.

  5. Urban artisanal gold shops and mercury emissions

    Energy Technology Data Exchange (ETDEWEB)

    Cordy, P.; Veiga, M.; Carrasco, V.H.G. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Mining and Mineral Process Engineering

    2008-07-01

    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.

  6. Software for virtual accelerator designing

    International Nuclear Information System (INIS)

    Kulabukhova, N.; Ivanov, A.; Korkhov, V.; Lazarev, A.

    2012-01-01

    The article discusses appropriate technologies for software implementation of the Virtual Accelerator. The Virtual Accelerator is considered as a set of services and tools enabling transparent execution of computational software for modeling beam dynamics in accelerators on distributed computing resources. Distributed storage and information processing facilities utilized by the Virtual Accelerator make use of the Service-Oriented Architecture (SOA) according to a cloud computing paradigm. Control system tool-kits (such as EPICS, TANGO), computing modules (including high-performance computing), realization of the GUI with existing frameworks and visualization of the data are discussed in the paper. The presented research consists of software analysis for realization of interaction between all levels of the Virtual Accelerator and some samples of middle-ware implementation. A set of the servers and clusters at St.-Petersburg State University form the infrastructure of the computing environment for Virtual Accelerator design. Usage of component-oriented technology for realization of Virtual Accelerator levels interaction is proposed. The article concludes with an overview and substantiation of a choice of technologies that will be used for design and implementation of the Virtual Accelerator. (authors)

  7. ABSTRACT MODELS FOR SYSTEM VIRTUALIZATION

    Directory of Open Access Journals (Sweden)

    M. G. Koveshnikov

    2015-05-01

    Full Text Available The paper is dedicated to issues of system objects securing (system files and user system or application configuration files against unauthorized access including denial of service attacks. We have suggested the method and developed abstract system virtualization models, which are used toresearch attack scenarios for different virtualization modes. Estimation for system tools virtualization technology effectiveness is given. Suggested technology is based on redirection of access requests to system objects shared among access subjects. Whole and partial system virtualization modes have been modeled. The difference between them is the following: in the whole virtualization mode all copies of access system objects are created whereon subjects’ requests are redirected including corresponding application objects;in the partial virtualization mode corresponding copies are created only for part of a system, for example, only system objects for applications. Alternative solutions effectiveness is valued relating to different attack scenarios. We consider proprietary and approved technical solution which implements system virtualization method for Microsoft Windows OS family. Administrative simplicity and capabilities of correspondingly designed system objects security tools are illustrated on this example. Practical significance of the suggested security method has been confirmed.

  8. Phytomining for Artisanal Gold Mine Tailings Management

    Directory of Open Access Journals (Sweden)

    Baiq Dewi Krisnayanti

    2016-08-01

    Full Text Available Mine tailings are generally disposed of by artisanal and small scale gold miners in poorly constructed containment areas and this leads to environmental risk. Gold phytomining could be a possible option for tailings management at artisanal and small-scale gold mining (ASGM locations where plants accumulate residual gold in their above ground biomass. The value of metal recovered from plants could offset some of the costs of environmental management. Getting gold into plants has been repeatedly demonstrated by many research groups; however, a simple working technology to get gold out of plants is less well described. A field experiment to assess the relevance of the technology to artisanal miners was conducted in Central Lombok, Indonesia between April and June 2015. Tobacco was planted in cyanidation tailings (1 mg/kg gold and grown for 2.5 months before the entire plot area was irrigated with NaCN to induce metal uptake. Biomass was then harvested (100 kg, air dried, and ashed by miners in equipment currently used to ash activated carbon at the end of a cyanide leach circuit. Borax and silver as a collector metal were added to the tobacco ash and smelted at high temperature to extract metals from the ash. The mass of the final bullion (39 g was greater than the mass of silver used as a collector (31 g, indicating recovery of metals from the biomass through the smelt process. The gold yield of this trial was low (1.2 mg/kg dry weight biomass concentration, indicating that considerable work must still be done to optimise valuable metal recovery by plants at the field scale. However, the described method to process the biomass was technically feasible, and represents a valid technique that artisanal and small-scale gold miners are willing to adopt if the economic case is good.

  9. Virtual agents in a simulated virtual training environment

    Science.gov (United States)

    Achorn, Brett; Badler, Norman L.

    1993-01-01

    A drawback to live-action training simulations is the need to gather a large group of participants in order to train a few individuals. One solution to this difficulty is the use of computer-controlled agents in a virtual training environment. This allows a human participant to be replaced by a virtual, or simulated, agent when only limited responses are needed. Each agent possesses a specified set of behaviors and is capable of limited autonomous action in response to its environment or the direction of a human trainee. The paper describes these agents in the context of a simulated hostage rescue training session, involving two human rescuers assisted by three virtual (computer-controlled) agents and opposed by three other virtual agents.

  10. Shader Lamps Virtual Patients: the physical manifestation of virtual patients.

    Science.gov (United States)

    Rivera-Gutierrez, Diego; Welch, Greg; Lincoln, Peter; Whitton, Mary; Cendan, Juan; Chesnutt, David A; Fuchs, Henry; Lok, Benjamin

    2012-01-01

    We introduce the notion of Shader Lamps Virtual Patients (SLVP) - the combination of projector-based Shader Lamps Avatars and interactive virtual humans. This paradigm uses Shader Lamps Avatars technology to give a 3D physical presence to conversational virtual humans, improving their social interactivity and enabling them to share the physical space with the user. The paradigm scales naturally to multiple viewers, allowing for scenarios where an instructor and multiple students are involved in the training. We have developed a physical-virtual patient for medical students to conduct ophthalmic exams, in an interactive training experience. In this experience, the trainee practices multiple skills simultaneously, including using a surrogate optical instrument in front of a physical head, conversing with the patient about his fears, observing realistic head motion, and practicing patient safety. Here we present a prototype system and results from a preliminary formative evaluation of the system.

  11. Modeling Virtual Organization Architecture with the Virtual Organization Breeding Methodology

    Science.gov (United States)

    Paszkiewicz, Zbigniew; Picard, Willy

    While Enterprise Architecture Modeling (EAM) methodologies become more and more popular, an EAM methodology tailored to the needs of virtual organizations (VO) is still to be developed. Among the most popular EAM methodologies, TOGAF has been chosen as the basis for a new EAM methodology taking into account characteristics of VOs presented in this paper. In this new methodology, referred as Virtual Organization Breeding Methodology (VOBM), concepts developed within the ECOLEAD project, e.g. the concept of Virtual Breeding Environment (VBE) or the VO creation schema, serve as fundamental elements for development of VOBM. VOBM is a generic methodology that should be adapted to a given VBE. VOBM defines the structure of VBE and VO architectures in a service-oriented environment, as well as an architecture development method for virtual organizations (ADM4VO). Finally, a preliminary set of tools and methods for VOBM is given in this paper.

  12. A Review on Virtual Reality

    OpenAIRE

    Pallavi Halarnkar; Sahil Shah; Harsh Shah; Hardik Shah; Anuj Shah

    2012-01-01

    Virtual Reality is a major asset and aspect of our future. It is the key to experiencing, feeling and touching the past, present and the future. It is the medium of creating our own world, our own customized reality. It could range from creating a video game to having a virtual stroll around the universe, from walking through our own dream house to experiencing a walk on an alien planet. With virtual reality, we can experience the most intimidating and gruelling situations by playing safe and...

  13. ACE Strategy with Virtual Channels

    Directory of Open Access Journals (Sweden)

    T. Tichy

    2008-12-01

    Full Text Available Cochlear implant is an electronic device, which can mediate hearing sensations to profoundly deaf people. Contemporary cochlear implants are sophisticated electronic devices; however, their performance could still be improved. This paper describes an experiment we made in that direction: additional 21 virtual channels were implemented by sequential stimulation of adjacent intracochlear electrodes, and the ACE strategy with virtual channels (ACEv, Advanced Combination Encoder strategy with virtual channels for the Nucleus® 24 Cochlear Implant System was created and verified in a clinical test with four patients.

  14. Virtual reality for spherical images

    Science.gov (United States)

    Pilarczyk, Rafal; Skarbek, Władysław

    2017-08-01

    Paper presents virtual reality application framework and application concept for mobile devices. Framework uses Google Cardboard library for Android operating system. Framework allows to create virtual reality 360 video player using standard OpenGL ES rendering methods. Framework provides network methods in order to connect to web server as application resource provider. Resources are delivered using JSON response as result of HTTP requests. Web server also uses Socket.IO library for synchronous communication between application and server. Framework implements methods to create event driven process of rendering additional content based on video timestamp and virtual reality head point of view.

  15. Reconciling Virtual Classes with Genericity

    DEFF Research Database (Denmark)

    Ernst, Erik

    2006-01-01

    is functional abstraction, yielding more precise knowledge about the outcome; the prime ex- ample is type parameterized classes. This paper argues that they should be clearly separated to work optimally. We have applied this design philosophy to a lan- guage based on an extension mechanism, namely virtual...... classes. As a result, a kind of type parameters have been introduced, but they are simple and only used where they excel. Conversely, final definitions of virtual classes have been re- moved from the language, thus making virtual classes more flexible. The result- ing language presents a clearer and more...

  16. VIRTUAL AND PHYSICAL ARCHITECTURAL ATMOSPHERE

    DEFF Research Database (Denmark)

    Hermund, Anders; Klint, Lars

    2016-01-01

    Models in Virtual Reality. 60 test persons experienced a specific test space as either a physical or a virtual environment, while data from their experiences was collected through a quantitative/qualitative questionnaire. The overall conclusion, from this phase of the study, is that even a simple BIM......This study, of the similarities between the perception of architectural space experienced in physical space conditions and in Virtual Reality, intents to clarify to what extend subjective and objective attributes of architectural space can be conveyed through a direct use of Building Information...

  17. The giant Kalgoorlie Gold Field revisited

    Directory of Open Access Journals (Sweden)

    Noreen Mary Vielreicher

    2016-05-01

    Direct timing constraints on gold mineralization indicate that Fimiston- and Mt Charlotte-style mineralization formed within a relative short period of time around 2.64 Ga, and, as such, support a model of progressive deformation of a rheologically heterogeneous rock package late in the structural history. Fluid characteristics, combined with the structural, metamorphic and absolute timing, support description of gold mineralization at the Golden Mile as orogenic and mesozonal, and this allows direct correlation with orogenic gold deposits worldwide, which classically formed during accretion along convergent margins throughout Earth history.

  18. Integer conductance quantization of gold atomic sheets

    Science.gov (United States)

    Kurui, Yoshihiko; Oshima, Yoshifumi; Okamoto, Masakuni; Takayanagi, Kunio

    2008-04-01

    Using a transmission electron microscope combined with a scanning tunneling microscope, we find that a gold (111) or (001) atomic sheet is formed between two gold electrodes. Simultaneous conductance measurements indicate a value in the vicinity of G0 ( =2e2/h : conductance quantum), 2G0 , 3G0 , and 4G0 . Each quantum number is equal to the number of atomic strands. First-principle calculations suggest that the atomic sheet should be deformed to explain this rule. It is likely that the gold atomic sheet is stabilized by an increment of the nonlocal bond because of the deformation.

  19. Synthesis of gold nanoparticles with graphene oxide.

    Science.gov (United States)

    Wang, Wenshuo; He, Dawei; Zhang, Xiqing; Duan, Jiahua; Wu, Hongpeng; Xu, Haiteng; Wang, Yongsheng

    2014-05-01

    Single sheets of functionalized graphene oxide are derived through chemical exfoliation of natural flake graphite. We present an effective synthetic method of graphene-gold nanoparticles hybrid nanocomposites. AFM (Atomic Force Microscope) was used to measure the thickness of the individual GO nanosheet. FTIR (Fourier transform infrared) spectroscopy was used to verify the attachment of oxygen functionalities on the surface of graphene oxide. TEM (Transmission Electron Microscope) data revealed the average diameters of the gold colloids and characterized the composite particles situation. Absorption spectroscopy showed that before and after synthesis the gold particle size did not change. Our studies indicate that the hybrid is potential substrates for catalysts and biosensors.

  20. Gold nanoparticles extraction from dielectric scattering background

    Science.gov (United States)

    Hong, Xin; Wang, Jingxin

    2014-11-01

    The unique advantages such as brightness, non-photobleaching, good bio-compatibility make gold nanoparticles desirable labels and play important roles in biotech and related research and applications. Distinguishing gold nanoparticles from other dielectric scattering particles is of more importance, especially in bio-tracing and imaging. The enhancement image results from the localized surface plasmon resonance associated with gold nanopartilces makes themselves distinguishable from other dielectric particles, based on which, we propose a dual-wavelength detection method by employing a high sensitive cross-polarization microscopy.