69 results
Search Results
2. NATURAL AND ANTROPIC TOURIST POTENTIAL IN TRANSILVANIA.
- Author
-
PLEȘOIANU, Daniela and GRECU, Edith
- Subjects
NATURE reserves ,WINTER resorts ,NATIONAL parks & reserves ,CULTURAL property ,STATISTICS - Abstract
This paper is an analysis of Transylvania regarding the natural and anthropic potential of the Transylvania region. In this paper we used methods such as cartographic description, analytical method and graphics. These methods helped to translate data into charts, tables and charts using the EXCEL program. The paper is based on documentation, analysis of statistical and territorial data research, integration and complex interpretation of information. The integration of all geographic information allowed, through complex interpretation and their transposition into representative maps, the knowledge and understanding of the natural and anthropic tourism potential in Transylvania. The data used were provided by the following institutions: Counties Councils, County Development Strategy 2007 - 2013, National Institute of Statistics, ADR Central analysis "Balnear tourismeconomic domain with potential development in the Center Region". Regarding the natural tourist potential of the area within the region, there are natural and national parks (eg Cheile Bicazului-Hăşmaş National Park), nature reserves (eg Aiud Cheile, Cheile Râmeţului, Cheile Întregalde), winter resorts (eg: Predeal, Păltiniş) and spa resorts. The cultural and historical heritage is also complex and includes ancient vestiges (eg: The remains of the Roman castles Apulum), cities with a complex cultural heritage (eg Brasov, Sibiu), fortified churches and fortresses (eg Prejmer Church, Viscri, Saschiz, Rupea Fortress, Râşnov Fortress), castles and palaces (eg Bran Castle, Brukenthal Palace), monasteries (eg Sâmbăta de Sus). [ABSTRACT FROM AUTHOR]
- Published
- 2018
3. Current Eco-friendly and Sustainable Methods for Heavy Metals Remediation of Contaminated Soil and Water: Special Emphasis on Use of Genetic Engineering and Nanotechnology.
- Author
-
Yadav, Meena and Sharma, Poonam
- Subjects
BIOREMEDIATION ,SOIL remediation ,GENETIC engineering ,NANOTECHNOLOGY ,SUSTAINABLE development ,HEAVY metal content of water - Abstract
Anthropogenic activities have polluted soil and aquatic ecosystems by introducing harmful heavy metals (HMs) such as cadmium, copper, mercury, lead, manganese, nickel, zinc, and others. These HMs lead to serious health conditions in humans like cancer, skin lesions, birth defects, liver and kidney damage, and mental retardation leading to other disabilities. Conventional methods of HM remediation of contaminated soil and water include physical, chemical, biological, and integrated methods. The use of physical and chemical methods, in isolation, has been reduced in practice, owing to their negative impacts, however, work on suitable integrated approaches, and the use of organisms for HM remediation has been in steady progress since past few decades. These approaches have proved to be eco-friendly, cost-effective, and show reduced negative impacts on the environment and biota. However, there is consistent increase in anthropogenic contribution to this problem, so, to keep pace with it, more recently work is in advancement on exploiting the biological system to increase the efficiency of bioremediation, using the latest technologies such as genetic engineering and nanotechnology. This paper provides an overview of the current methods deployed to address this problem; developments made in this field in past few decades, and evokes a research thrust that might lead to novel remediation approaches in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
4. Studies on regional ozone formation sensitivities and transport with higher spatiotemporal resolutions in a stereoscopic dimension: GEMS and vertical observations.
- Author
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Peng, Haochen, Xing, Chengzhi, Li, Yikai, Zhang, Chengxin, Lin, Jinan, Xue, Jingkai, Wang, Xiaohan, Song, Yuhang, Niu, Xinhan, and Liu, Cheng
- Subjects
- *
PROJECT POSSUM , *TROPOSPHERIC ozone , *OZONE , *ENVIRONMENTAL monitoring , *ORBITS (Astronomy) , *SENSITIVITY analysis , *POLLUTANTS - Abstract
Currently, ozone pollution is one of the key environmental concerns, and to provide more effective strategies for ozone control, this paper proposes the use of the Geostationary Environmental Monitoring Spectrometer (GEMS) in conjunction with MAX-DOAS for observations and ozone sensitivity analysis. Compared to traditional polar-orbiting satellites, GEMS, launched by South Korea in 2019, offers superior spatiotemporal resolution. However, there is a lack of ground validation for GEMS data related to ozone and its precursors. In this study, we conducted validation in the Jing-Jin-Ji (Beijing-Tianjin-Hebei) region using two typical MAX-DOAS sites and the China National Environmental Monitoring Center (CNEMC) sites, confirming the accuracy of GEMS data. Analysis of the seasonal horizontal distribution results from GEMS and vertical distribution results from MAX-DOAS in 2022 reveals that the concentrations of NO 2 , HCHO, O 3 , and ozone sensitivity not only display seasonality and regional variations but also exhibit distinct characteristics at different altitudes and times, influenced by local climatic conditions, human activities, and topography. When formulating ozone control policies, it becomes imperative to consider factors such as time, regional characteristics, and seasonality. Comparisons between daily results from TROPOMI and GEMS indicate that polar-orbiting satellites may overlook high-pollution periods within a single day, and their measurements may not provide a comprehensive representation of an entire day's data. Consequently, relying solely on polar-orbiting satellite data for shaping ozone prevention and control policies may inadvertently encourage ozone formation during specific time periods, rendering these policies ineffective. Therefore, leveraging GEMS is essential for the development of comprehensive, around-the-clock ozone control policies. Finally, we used monitoring data from Beijing on October 6, 2022, to illustrate how the combination of GEMS and MAX-DOAS enables three-dimensional monitoring of pollutant transport processes on an hourly scale. [Display omitted] • Validation of the accuracy of ozone and its precursor data from GEMS. • Analysis of hourly ozone sensitivity level distribution using GEMS. • Limitations of polar orbit satellites in O 3 sensitivity analysis compared to GEMS. • Observation of the transport of pollutants combining GEMS and MAX-DOAS. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
5. Les images sérielles sur les sceaux, les intailles et les verres moulés
- Author
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Laura Sageaux
- Subjects
Mould ,Coins ,Gems ,Glass Pastes ,Monetary Type ,Matrix ,Social Sciences - Abstract
The study of Hellenistic and Roman gems and seals in the light of the notion of “series” provides a better understanding of how engraved images were conceived in Greco-Roman antiquity. Two recurring types of iconographic series are presented here: series that display a motif whose model is most likely a monetary type, and series of glass pastes, produced from a mould bearing the impression of a die. A comparative study of gems and coins can help to better situate in time the variations observed within a relatively homogeneous series. This paper is also an opportunity to recall the methodological approach that makes it possible to bring together the glass pastes produced by the same mould – these objects are indeed often scattered in various collections.
- Published
- 2024
- Full Text
- View/download PDF
6. THE IMPACT OF THE PONIATOWSKI GEMS ON LATER GEM ENGRAVING.
- Author
-
Gołyźniak, Paweł
- Subjects
19TH century engraving ,GEMSTONE collecting ,NATIONAL museums ,HAMMERS ,CULTURAL property - Abstract
In the first half of the 19th century, the Prince Stanislas Poniatowski (1754-1833) collection of engraved gems was considered to be one of the most outstanding known assemblages. However, its sale at Christie's in 1839 was a disaster, as the cabinet turned out to include almost only neo-classical specimens and, thus, half of the gems did not go under the hammer. But these intaglios and cameos, and especially the themes they bear, portray in their beauty an effort to re-create a lost neo-classical world as reflected in the texts of Homer, Vergil, and other ancient authors. In contrary to other works on the Poniatowski gems, this paper focuses not on the collection itself, but on its impact on the later gem engraving. It presents two intaglios from the collection of the National Museum in Krakow. The first presents a scene of Hebe pouring out nectar for Jupiter (with an eagle behind him). The second depicts a crowned snake-god with the incorrect Latin inscription: VOT•SOL•CER. They are faithful copies of two Poniatowski gems. In fact, the first gem testifies to the great contribution of the Poniatowski collection to the reception of Classical culture, while the other is a falsification of the original which reflects a later collector's aim to possess a 'Poniatowski gem'. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
7. A Fast Retrieval of Cloud Parameters Using a Triplet of Wavelengths of Oxygen Dimer Band around 477 nm.
- Author
-
Choi, Haklim, Liu, Xiong, Gonzalez Abad, Gonzalo, Seo, Jongjin, Lee, Kwang-Mog, and Kim, Jhoon
- Subjects
OPTICAL polarization ,TRACE gases ,WAVELENGTHS ,RADIATIVE transfer ,OXYGEN ,RADIANCE ,TROPOSPHERIC aerosols - Abstract
Clouds act as a major reflector that changes the amount of sunlight reflected to space. Change in radiance intensity due to the presence of clouds interrupts the retrieval of trace gas or aerosol properties from satellite data. In this paper, we developed a fast and robust algorithm, named the fast cloud retrieval algorithm, using a triplet of wavelengths (469, 477, and 485 nm) of the O
2 –O2 absorption band around 477 nm (CLDTO4) to derive the cloud information such as cloud top pressure (CTP) and cloud fraction (CF) for the Geostationary Environment Monitoring Spectrometer (GEMS). The novel algorithm is based on the fact that the difference in the optical path through which light passes with regard to the altitude of clouds causes a change in radiance due to the absorption of O2 –O2 at the three selected wavelengths. To reduce the time required for algorithm calculations, the look-up table (LUT) method was applied. The LUT was pre-constructed for various conditions of geometry using Vectorized Linearized Discrete Ordinate Radiative Transfer (VLIDORT) to consider the polarization of the scattered light. The GEMS was launched in February 2020, but the observed data of GEMS have not yet been widely released. To evaluate the performance of the algorithm, the retrieved CTP and CF using observational data from the Global Ozone Monitoring Experiment-2 (GOME-2), which cover the spectral range of GEMS, were compared with the results of the Fast Retrieval Scheme for Clouds from the Oxygen A band (FRESCO) algorithm, which is based on the O2 A-band. There was good agreement between the results, despite small discrepancies for low clouds. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
8. GEO-KOMPSAT-2A/2B AMI/GOCI-II/GEMS Data & Products
- Author
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Sungsik Huh and Kyoung-Wook Jin
- Subjects
ami ,goci-ii ,gems ,geo-kompsat-2a ,geo-kompsat-2b ,geostationary satellite ,Environmental sciences ,GE1-350 ,Geology ,QE1-996.5 - Abstract
Two geostationary satellites developed by the Korea Aerospace Research Institute and currently in operation are the GEO-KOMPSAT-2A (GK-2A) and the GEO-KOMPSAT-2B (GK-2B). The main instruments mounted on these satellites are the Advanced Meteorological Imager (AMI), the Geostationary Ocean Color Imager (GOCI-II) and the Geostationary Environment Monitoring Spectrometer (GEMS). This paper briefly introduced the GK-2A and GK-2B programs including measurement principles and elements of the instruments. Moreover, the data formats, operational products, and applications are summarized.
- Published
- 2022
- Full Text
- View/download PDF
9. Spectral Calibration Algorithm for the Geostationary Environment Monitoring Spectrometer (GEMS).
- Author
-
Kang, Mina, Ahn, Myoung-Hwan, Liu, Xiong, Jeong, Ukkyo, and Kim, Jhoon
- Subjects
ALGORITHMS ,SPECTROMETERS ,SPECTRAL irradiance ,SPECTRAL sensitivity ,CALIBRATION ,ANALYTIC functions ,SOLAR spectra ,PARTIAL least squares regression - Abstract
The Geostationary Environment Monitoring Spectrometer (GEMS) onboard the Geostationary Korean Multi-Purpose Satellite 2B was successfully launched in February 2020. GEMS is a hyperspectral spectrometer measuring solar irradiance and Earth radiance in the wavelength range of 300 to 500 nm. This paper introduces the spectral calibration algorithm for GEMS, which uses a nonlinear least-squares approach. Sensitivity tests for a series of unknown algorithm parameters such as spectral range for fitting, spectral response function (SRF), and reference spectrum were conducted using the synthetic GEMS spectrum prepared with the ground-measured GEMS SRF. The test results show that the required accuracy of 0.002 nm is achievable provided the SRF and the high-resolution reference spectrum are properly prepared. Such a satisfactory performance is possible mainly due to the inclusion of additional fitting parameters of spectral scales (shift, squeeze, and high order shifts) and SRF (width, shape and asymmetry). For the application to the actual GEMS data, in-orbit SRF is to be monitored using an analytic SRF function and the measured GEMS solar irradiance, while a reference spectrum is going to be selected during the instrument in-orbit test. The calibrated GEMS data is expected to be released by the end of 2020. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
10. The New Potential of Deep Convective Clouds as a Calibration Target for a Geostationary UV/VIS Hyperspectral Spectrometer.
- Author
-
Lee, Yeeun, Ahn, Myoung-Hwan, and Kang, Mina
- Subjects
CONVECTIVE clouds ,CIRRUS clouds ,CALIBRATION ,SPECTROMETERS ,GEOSTATIONARY satellites - Abstract
As one of geostationary earth orbit constellation for environmental monitoring over the next decade, the Geostationary Environment Monitoring Spectrometer (GEMS) has been designed to observe the Asia-Pacific region to provide information on atmospheric chemicals, aerosols, and cloud properties. In order to continuously monitor sensor performance after its launch in early 2020, we suggest in this paper deep convective clouds (DCCs) as a possible target for the vicarious calibration of the GEMS, the first ultraviolet and visible hyperspectral sensor onboard a geostationary satellite. The Tropospheric Monitoring Instrument (TROPOMI) and the Ozone Monitoring Instrument (OMI) are used as a proxy for GEMS, and a conventional DCC-detection approach applying a thermal threshold test is used for DCC detection based on collocations with the Advanced Himawari Imager (AHI) onboard the Himawari-8 geostationary satellite. DCCs are frequently detected over the GEMS observation area at an average of over 200 pixels within a single observation scene. Considering the spatial resolution of the GEMS (3.5 × 8 km
2 ), which is similar to the TROPOMI and its temporal resolution (eight times a day), the availability of DCCs is expected to be sufficient for the vicarious calibration of the GEMS. Inspection of the DCC reflectivity spectra estimated from OMI and TROPOMI data also shows promising results. The estimated DCC spectra are in good agreement within a known uncertainty range with comparable spectral features even with different observation geometries and sensor characteristics. When DCC detection is improved further by applying both visible and infrared tests, the variability of DCC reflectivity from TROPOMI data is reduced from 10% to 5%. This is mainly due to the efficient screening out of cold, thin cirrus clouds in the visible test and of bright, warm clouds in the infrared test. Precise DCC detection is also expected to contribute to the accurate characterization of cloud reflectivity, which will be investigated further in future research. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
11. GEMs and amplitude bounds in the colored Boulatov model
- Author
-
Caravelli, Francesco
- Published
- 2013
- Full Text
- View/download PDF
12. Trace gas/aerosol boundary concentrations and their impacts on continental-scale AQMEII modeling domains
- Author
-
Schere, Kenneth, Flemming, Johannes, Vautard, Robert, Chemel, Charles, Colette, Augustin, Hogrefe, Christian, Bessagnet, Bertrand, Meleux, Frederik, Mathur, Rohit, Roselle, Shawn, Hu, Rong-Ming, Sokhi, Ranjeet S., Rao, S. Trivikrama, and Galmarini, Stefano
- Subjects
- *
TRACE gases , *AEROSOLS , *COMPARATIVE studies , *PHOTOCHEMICAL smog , *EMISSIONS (Air pollution) , *AIR quality , *SPATIAL analysis (Statistics) - Abstract
Abstract: Over twenty modeling groups are participating in the Air Quality Model Evaluation International Initiative (AQMEII) in which a variety of mesoscale photochemical and aerosol air quality modeling systems are being applied to continental-scale domains in North America and Europe for 2006 full-year simulations for model inter-comparisons and evaluations. To better understand the reasons for differences in model results among these participating groups, each group was asked to use the same source of emissions and boundary concentration data for their simulations. This paper describes the development and application of the boundary concentration data for this AQMEII modeling exercise. The European project known as GEMS (Global and regional Earth-system Monitoring using Satellite and in-situ data) has produced global-scale re-analyses of air quality for several years, including 2006 (http://gems.ecmwf.int). The GEMS trace gas and aerosol data were made available at 3-hourly intervals on a regular latitude/longitude grid of approximately 1.9° resolution within 2 “cut-outs” from the global model domain. One cut-out was centered over North America and the other over Europe, covering sufficient spatial domain for each modeling group to extract the necessary time- and space-varying (horizontal and vertical) concentrations for their mesoscale model boundaries. Examples of the impact of these boundary concentrations on the AQMEII continental simulations are presented to quantify the sensitivity of the simulations to boundary concentrations. In addition, some participating groups were not able to use the GEMS data and instead relied upon other sources for their boundary concentration specifications. These are noted, and the contrasting impacts of other data sources for boundary data are presented. How one specifies four-dimensional boundary concentrations for mesoscale air quality simulations can have a profound impact on the model results, and hence, this aspect of data preparation must be performed with considerable care. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
13. An Archaeometric Investigation of Gems and Glass Beads Decorating the Double-Arm Reliquary Cross from Liège, Belgium.
- Author
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Bruni, Yannick, Hatert, Frédéric, Demaude, Merry, Delmelle, Nicolas, George, Philippe, and Maquet, Julien
- Subjects
ARCHAEOMETRY ,GLASS beads ,RELIQUARIES ,X-ray fluorescence ,DATA acquisition systems - Abstract
In 1914, a magnificent reliquary cross dating from the early XIIIth century was discovered in a safe from the Liège Cathedral. This double-arm cross shows a wooden structure, covered by gold-coated copper on the front, and by carved silver plates on the back. Its total length is 34 cm, and it is covered by filigrees, gems, glass beads, and pearls on its front. The reliquary cross was analysed by Raman spectrometry and X-ray fluorescence spectrometry (pXRF) to determine the mineralogical and chemical compositions of gems, glass beads, and metals that have been used to decorate it. The results confirm the identification of twenty-five turquoises from Egypt, one garnet from Sri Lanka, as well as six quartz and one opal whose origin is difficult to certify. Twelve glass beads, showing green, blue, or amber tints, were also identified. Their compositions either correspond to soda lime glasses with natron or to potash–lead glasses similar to those of Central Europe. Moreover, a small polished red cross and a green stone appear to be constituted by nice doublets, composed of coloured glass covered by quartz. The filigrees contain Au and Cu, while carved plates covering the edges and the back of the cross are made of silver. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
14. Increased glucosylceramide production leads to decreased cell energy metabolism and lowered tumor marker expression in non-cancerous liver cells
- Author
-
Wegner, Marthe-Susanna, Schömel, Nina, Olzomer, Ellen M., Trautmann, Sandra, Olesch, Catherine, Byrne, Frances L., Brüne, Bernhard, Gurke, Robert, Ferreirós, Nerea, Weigert, Andreas, Geisslinger, Gerd, and Hoehn, Kyle L.
- Published
- 2021
- Full Text
- View/download PDF
15. Medical Applications of the GEMPix.
- Author
-
Leidner, Johannes, Murtas, Fabrizio, and Silari, Marco
- Subjects
PHOTOMULTIPLIERS ,ELECTRON gas ,PHOTON emission ,GAS flow ,PHOTON beams ,GAS mixtures ,ION beams - Abstract
The GEMPix is a small gaseous detector with a highly pixelated readout, consisting of a drift region, three Gas Electron Multipliers (GEMs) for signal amplification, and four Timepix ASICs with 55 µm pixel pitch and a total of 262,144 pixels. A continuous flow of a gas mixture such as Ar:CO
2 :CF4 , Ar:CO2 or propane-based tissue equivalent gas is supplied externally at a rate of 5 L/h. This article reviews the medical applications of the GEMPix. These include relative dose measurements in conventional photon radiation therapy and in carbon ion beams, by which on-line 2D dose images provided a similar or better performance compared to gafchromic films. Depth scans in a water phantom with12 C ions allowed measuring the 3D energy deposition and reconstructing the Bragg curve of a pencil beam. Microdosimetric measurements performed in neutron and photon fields allowed comparing dose spectra with those from Tissue Equivalent Proportional Counters and, additionally, to obtain particle track images. Some preliminary measurements performed to check the capabilities as the detector in proton tomography are also illustrated. The most important on-going developments are: (1) a new, larger area readout to cover the typical maximum field size in radiation therapy of 20 × 20 cm2 ; (2) a sealed and low-pressure version to facilitate measurements and to increase the equivalent spatial resolution for microdosimetry; (3) 3D particle track reconstruction when operating the GEMPix as a Time Projection Chamber. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
16. One-pot synthesis of 3,5-diaryl substituted-1,2,4-oxadiazoles using gem-dibromomethylarenes
- Author
-
Vinaya, Kambappa, Chandrashekara, Ganganahalli K., and Shivaramu, Prasanna D.
- Subjects
Gems ,Organic acids ,Benzoic acid ,Precious stones ,Chemistry - Abstract
1,2,4-Oxadiazole is one of the most promising heterocyclic ring systems in medicinal chemistry. In the present paper, we report the method for an efficient one-pot synthesis of 3,5-diaryl substituted 1,2,4-oxadiazoles using a two-component reaction of gem-dibromomethylarenes with amidoximes in good yields. In this method, gem-dibromomethylarenes are used as benzoic acid equivalents for the efficient synthesis of aryl-substituted 1,2,4-oxadiazoles. It is anticipated that this methodology will have versatile applications in the practical syntheses of various molecules of both medicinal and material chemistry importance. Key words: gem-dibromomethylarene, oxadiazole, amidoxime. Le 1,2,4-oxadiazole est l'un des systemes heterocycliques les plus prometteurs en chimie medicinale. Dans le cadre du present article, nous presentons une methode efficace pour la synthese de 1,2,4-oxadiazoles 3,5-diaryliques avec de bons rendements, par reaction a deux composants en recipient unique entre des gem-dibromomethylarenes et des amidoximes. Dans cette methode, les gem-dibromomethylarenes sont employes comme equivalents de l'acide benzoïque pour realiser efficacement la synthese de 1,2,4-oxadiazoles portant des substituants aryles. Il est a prevoir que cette methode trouvera des applications polyvalentes pour la synthese pratique de molecules diverses qui revêtent une importance dans les domaines de chimie medicinale et de la chimie des materiaux. [Traduit par la Redaction] Mots-cles : gem-dibromomethylarene, oxadiazole, amidoxime., Introduction 1,2,4-Oxadiazoles are being considered as one of the most important structural motifs in the research area of drug discovery. They are often considered as ester and amide bioisosteres and [...]
- Published
- 2019
- Full Text
- View/download PDF
17. Dubious Actions Coming to Light: The Role of ‘Talking’ Gems as Indicators of Virtuousness
- Author
-
Florian Nieser
- Subjects
materiality ,inscription ,gems ,gregorius ,willehalm ,wilhelm von österreich ,middle ages ,History (General) ,D1-2009 ,Medieval history ,D111-203 - Abstract
This paper is dedicated to the speaking capabilities of gemstones, their mobility and their function of reminding us of elements hidden or repressed in the text. It will be shown that inscriptions made of gemstones shaped as words do not necessarily depend on the ‚arbitrariness‘ of their recipients. At the center is the wax tablet of Gregorius in Hartmann von Aue’s narrative, whose special material composition of partly perishable and partly durable materials is reassessed in comparative analysis of the epitaphs of fallen kings in Willehalm by Wolfram von Eschenbach and the Cupido-helmet from Wilhelm von Österreich by John of Wuerzburg. The focus in the contemplation of Gregorius‘ wax tablet changes from the weathered inscription on the tablet, which is no longer able to tell of the sinful past, to the weatherproof and gem-studded framing of this inscription, which materially stages the protagonist’s iridescent character biography. | Dieser Beitrag widmet sich der ‚Sprachfähigkeit‘ von Edelsteinen, ihrer Mobilität und ihrer erinnernden Funktion an im Text verheimlichte oder zurückgedrängte Elemente. Es soll gezeigt werden, dass Inschriften, die mittels zu Wörtern geformten Edelsteinen angefertigt wurden, nicht zwingend von der ‚Willkür‘ ihrer Rezipienten abhängen. Im Zentrum steht die Wachstafel des Gregorius in der Erzählung Hartmanns von Aue, deren besondere materielle Beschaffenheit aus teils vergänglichen und teils beständigen Materialien in vergleichender Analyse der Epitaphe gefallener Könige im Willehalm Wolframs von Eschenbach und dem Cupido-Helm aus dem Wilhelm von Österreich Johanns von Würzburg neu betrachtet wird. Der Fokus in der Betrachtung der Wachstafel des Gregorius wechselt von der verwitterten Inschrift auf der Tafel, die nicht mehr von der sündhaften Vergangenheit berichten kann, zur witterungsbeständigen und edelsteinbesetzten Rahmung dieser Inschrift, die die schillernde Figurenbiographie des Protagonisten materiell in Szene setzt.
- Published
- 2020
- Full Text
- View/download PDF
18. Genome-Scale Metabolic Modeling of Glioblastoma Reveals Promising Targets for Drug Development.
- Author
-
Larsson, Ida, Uhlén, Mathias, Zhang, Cheng, and Mardinoglu, Adil
- Subjects
GLIOBLASTOMA multiforme ,METABOLIC models ,DRUG development ,BRAIN tumors ,TARGETED drug delivery ,BIOLOGICAL invasions ,SYSTEMS biology - Abstract
Glioblastoma (GBM) is an aggressive type of brain cancer with a poor prognosis for affected patients. The current line of treatment only gives the patients a survival time of on average 15 months. In this work, we use genome-scale metabolic models (GEMs) together with other systems biology tools to examine the global transcriptomics-data of GBM-patients obtained from The Cancer Genome Atlas (TCGA). We reveal the molecular mechanisms underlying GBM and identify potential therapeutic targets for effective treatment of patients. The work presented consists of two main parts. The first part stratifies the patients into two groups, high and low survival, and compares their gene expression. The second part uses GBM and healthy brain tissue GEMs to simulate gene knockout in a GBM cell model to find potential therapeutic targets and predict their side effect in healthy brain tissue. We (1) find that genes upregulated in the patients with low survival are linked to various stages of the glioma invasion process, and (2) identify five essential genes for GBM, whose inhibition is non-toxic to healthy brain tissue, therefore promising to investigate further as therapeutic targets. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
19. Helicopter emergency medical service for time critical interfacility transfers of patients with cardiovascular emergencies
- Author
-
Meuli, Lorenz, Zimmermann, Alexander, Menges, Anna-Leonie, Tissi, Mario, Becker, Stefan, Albrecht, Roland, and Pietsch, Urs
- Published
- 2021
- Full Text
- View/download PDF
20. A Fast Retrieval of Cloud Parameters Using a Triplet of Wavelengths of Oxygen Dimer Band around 477 nm
- Author
-
Haklim Choi, Xiong Liu, Gonzalo Gonzalez Abad, Jongjin Seo, Kwang-Mog Lee, and Jhoon Kim
- Subjects
fast retrieval ,cloud top pressure ,cloud fraction ,oxygen dimer ,GEMS ,FRESCO ,Science - Abstract
Clouds act as a major reflector that changes the amount of sunlight reflected to space. Change in radiance intensity due to the presence of clouds interrupts the retrieval of trace gas or aerosol properties from satellite data. In this paper, we developed a fast and robust algorithm, named the fast cloud retrieval algorithm, using a triplet of wavelengths (469, 477, and 485 nm) of the O2–O2 absorption band around 477 nm (CLDTO4) to derive the cloud information such as cloud top pressure (CTP) and cloud fraction (CF) for the Geostationary Environment Monitoring Spectrometer (GEMS). The novel algorithm is based on the fact that the difference in the optical path through which light passes with regard to the altitude of clouds causes a change in radiance due to the absorption of O2–O2 at the three selected wavelengths. To reduce the time required for algorithm calculations, the look-up table (LUT) method was applied. The LUT was pre-constructed for various conditions of geometry using Vectorized Linearized Discrete Ordinate Radiative Transfer (VLIDORT) to consider the polarization of the scattered light. The GEMS was launched in February 2020, but the observed data of GEMS have not yet been widely released. To evaluate the performance of the algorithm, the retrieved CTP and CF using observational data from the Global Ozone Monitoring Experiment-2 (GOME-2), which cover the spectral range of GEMS, were compared with the results of the Fast Retrieval Scheme for Clouds from the Oxygen A band (FRESCO) algorithm, which is based on the O2 A-band. There was good agreement between the results, despite small discrepancies for low clouds.
- Published
- 2021
- Full Text
- View/download PDF
21. Spectral Calibration Algorithm for the Geostationary Environment Monitoring Spectrometer (GEMS)
- Author
-
Mina Kang, Myoung-Hwan Ahn, Xiong Liu, Ukkyo Jeong, and Jhoon Kim
- Subjects
GEMS ,spectral calibration ,hyperspectral instrument ,Science - Abstract
The Geostationary Environment Monitoring Spectrometer (GEMS) onboard the Geostationary Korean Multi-Purpose Satellite 2B was successfully launched in February 2020. GEMS is a hyperspectral spectrometer measuring solar irradiance and Earth radiance in the wavelength range of 300 to 500 nm. This paper introduces the spectral calibration algorithm for GEMS, which uses a nonlinear least-squares approach. Sensitivity tests for a series of unknown algorithm parameters such as spectral range for fitting, spectral response function (SRF), and reference spectrum were conducted using the synthetic GEMS spectrum prepared with the ground-measured GEMS SRF. The test results show that the required accuracy of 0.002 nm is achievable provided the SRF and the high-resolution reference spectrum are properly prepared. Such a satisfactory performance is possible mainly due to the inclusion of additional fitting parameters of spectral scales (shift, squeeze, and high order shifts) and SRF (width, shape and asymmetry). For the application to the actual GEMS data, in-orbit SRF is to be monitored using an analytic SRF function and the measured GEMS solar irradiance, while a reference spectrum is going to be selected during the instrument in-orbit test. The calibrated GEMS data is expected to be released by the end of 2020.
- Published
- 2020
- Full Text
- View/download PDF
22. The New Potential of Deep Convective Clouds as a Calibration Target for a Geostationary UV/VIS Hyperspectral Spectrometer
- Author
-
Yeeun Lee, Myoung-Hwan Ahn, and Mina Kang
- Subjects
gems ,uv ,vis ,hyperspectral data ,deep convective cloud ,vicarious calibration ,omi ,tropomi ,Science - Abstract
As one of geostationary earth orbit constellation for environmental monitoring over the next decade, the Geostationary Environment Monitoring Spectrometer (GEMS) has been designed to observe the Asia-Pacific region to provide information on atmospheric chemicals, aerosols, and cloud properties. In order to continuously monitor sensor performance after its launch in early 2020, we suggest in this paper deep convective clouds (DCCs) as a possible target for the vicarious calibration of the GEMS, the first ultraviolet and visible hyperspectral sensor onboard a geostationary satellite. The Tropospheric Monitoring Instrument (TROPOMI) and the Ozone Monitoring Instrument (OMI) are used as a proxy for GEMS, and a conventional DCC-detection approach applying a thermal threshold test is used for DCC detection based on collocations with the Advanced Himawari Imager (AHI) onboard the Himawari-8 geostationary satellite. DCCs are frequently detected over the GEMS observation area at an average of over 200 pixels within a single observation scene. Considering the spatial resolution of the GEMS (3.5 × 8 km2), which is similar to the TROPOMI and its temporal resolution (eight times a day), the availability of DCCs is expected to be sufficient for the vicarious calibration of the GEMS. Inspection of the DCC reflectivity spectra estimated from OMI and TROPOMI data also shows promising results. The estimated DCC spectra are in good agreement within a known uncertainty range with comparable spectral features even with different observation geometries and sensor characteristics. When DCC detection is improved further by applying both visible and infrared tests, the variability of DCC reflectivity from TROPOMI data is reduced from 10% to 5%. This is mainly due to the efficient screening out of cold, thin cirrus clouds in the visible test and of bright, warm clouds in the infrared test. Precise DCC detection is also expected to contribute to the accurate characterization of cloud reflectivity, which will be investigated further in future research.
- Published
- 2020
- Full Text
- View/download PDF
23. Henry Snowden Ward (1865-1911) Biography with special reference to X-rays in 1896.
- Author
-
Mould, Richard F.
- Subjects
RADIOGRAPHY ,SCANNING electron microscopy ,X-rays ,IONIZING radiation - Abstract
Henry Snowden Ward was a professional photographer, Editor of The Photogram magazine, itinerant lecturer in England in 1896 on X-rays, and the author of the world's first textbook on X-rays, Practical Radiography, which was first published in May 1896 and went into three editions with the later editions, 1898 and 1901, expanded and co- -authored with Adolph Isenthal (d~1910), a manufacturer in London of electrical apparatus and X-ray apparatus. Ward was a Fellow of the Royal Photographic Society and a founding member of the Röntgen Society. As with most early demonstrators of X-rays imaging, Snowden Ward left the field once qualified physicians, surgeons, physicists and engineers became more involved and took over as the prime leaders in X-ray diagnosis and therapy. Snowden Ward went on to publish and lecture on Charles Dickens, Geoffrey Chaucer's Canterbury Tales and William Shakespeare. He died suddenly in December 1911 in New York whilst on a Dickens & Shakespeare lecture tour of the USA. Some of the illustrations from the three editions of Practical Radiography are included. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
24. The Impact of the Poniatowski Gems on Later Gem Engraving
- Author
-
Paweł Gołyźniak
- Subjects
gems ,intaglios ,neo-classical ,Poniatowski ,reception ,Ancient history ,D51-90 ,History of the arts ,NX440-632 - Abstract
In the first half of the 19th century, the Prince Stanislas Poniatowski (1754–1833) collection of engraved gems was considered to be one of the most outstanding known assemblages. However, its sale at Christie’s in 1839 was a disaster, as the cabinet turned out to include almost only neo-classical specimens and, thus, half of the gems did not go under the hammer. But these intaglios and cameos, and especially the themes they bear, portray in their beauty an effort to re-create a lost neo-classical world as reflected in the texts of Homer, Vergil, and other ancient authors. In contrary to other works on the Poniatowski gems, this paper focuses not on the collection itself, but on its impact on the later gem engraving. It presents two intaglios from the collection of the National Museum in Krakow. The first presents a scene of Hebe pouring out nectar for Jupiter (with an eagle behind him). The second depicts a crowned snake-god with the incorrect Latin inscription: VOT•SOL•CER. They are faithful copies of two Poniatowski gems. In fact, the first gem testifies to the great contribution of the Poniatowski collection to the reception of Classical culture, while the other is a falsification of the original which reflects a later collector’s aim to possess a ‘Poniatowski gem’.
- Published
- 2016
- Full Text
- View/download PDF
25. Monsters, Chimeras, Masks or Gods?
- Author
-
Paweł Gołyźniak
- Subjects
Bes ,Constantine Schmidt-Ciążyński ,Dionysos ,double-headed device ,gems ,intaglios ,Ancient history ,D51-90 ,History of the arts ,NX440-632 - Abstract
The National Museum in Krakow contains an outstanding set of gems collected by Constantine Schmidt-Ciążyński (1818-1889). Within this extensive group of objects, two very rare intaglios bearing a particular intriguing motif, the double-headed device, stand out from the rest. Since the very beginning, scholars have interpreted this kind of depiction differently and many different hypotheses have been drawn. This paper aims to explain the meaning of this strange iconography and from whence it originated.
- Published
- 2013
- Full Text
- View/download PDF
26. The splicing factor U1-70K interacts with the SMN complex and is required for nuclear gem integrity.
- Author
-
Stejskalovâ, Eva and Stanëk, supDavid
- Subjects
NUCLEOPROTEINS ,SPLICEOSOMES ,COILED bodies (Cytology) ,N-terminal residues ,SMALL interfering RNA ,AMYOTROPHIC lateral sclerosis - Abstract
The nuclear SMN complex localizes to specific structures called nuclear gems. The loss of gems is a cellular marker for several neurodegenerative diseases. Here, we identify that the U1-snRNP-specific protein U1-70K localizes to nuclear gems, and we show that U1-70K is necessary for gem integrity. Furthermore, we show that the interaction between U1-70K and the SMN complex is RNA independent, and we map the SMN complex binding site to the unstructured N-terminal tail of U1-70K. Consistent with these results, the expression of the U1-70K N-terminal tail rescues gem formation. These findings show that U1-70K is an SMN-complex-associating protein, and they suggest a new function for U1-70K in the formation of nuclear gems. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
27. Nekoliko kameja iz Arheološkog muzeja u Splitu
- Author
-
Kaić, Iva
- Subjects
geme ,kameje ,gliptička zbirka ,Arheološki muzej u Splitu ,rimsko razdoblje ,novovjekovno razdoblje ,gems ,cameos ,glyptic collection ,Archaeological Museum in Split ,Roman era ,Early Modern era - Abstract
U Arheološkom muzeju u Splitu čuva se najbrojnija zbirka antičkih intalja i kameja u Hrvatskoj. U rukopisnom inventaru muzejskih gema, poznatom kao “Katalog I”, don Frane Bulić upisao je ukupno 2559 gema, od kojih je bilo 35 kameja. Do danas se sačuvalo 17 kameja, koje su jednim dijelom već objavljene ili je njihova objava u tisku. U ovom radu obrađuju se preostale četiri kameje i jedan gipsani odljev kameje iz tog inventarnog popisa. Za dva primjerka iz te skupine zabilježeno je mjesto njihova nalaza (Split i Konjsko), dok za preostala tri nije sačuvan taj podatak. Rimskom razdoblju pripada kameja s glavom dječaka/ Erosa i kameja s natpisom ΤΥΧΗ / ΚΑΛΗ, kao i gipsani odljev kameje s erotičnim motivom satira i menade. Novovjekovnom razdoblju pripadaju kameja s poprsjem mladog Afrikanca i kameja s ovjenčanom glavom muškarca., The Archaeological Museum in Split holds the largest collection of Roman-era intaglios and cameos in Croatia. In the Museum’s hand-written gem inventory, known as “Catalogue I”, Fr. Frane Bulić registered a total of 2,559 gems, of which 35 are cameos. Up to the present, 17 cameos have been preserved and they have been partially published or their publication is pending. The remaining four cameos and one plaster cast from that inventory list are covered in this paper. The find-spots of two examples from this group have been recorded (Split and Konjsko), while this information has not been preserved for the other three. The cameo bearing the head of a boy/Eros and the inscription ΤΥΧΗ/ΚΑΛΗ dates to the Roman era, as does the plaster cameo featuring an erotic motif of a satyr and maenad. The cameo with a bust of a young African man and the cameo featuring a laureate man’s head date to the Early Modern period.
- Published
- 2020
28. Applications of Raman spectroscopy to gemology.
- Author
-
Bersani, Danilo and Lottici, Pier Paolo
- Subjects
RAMAN spectroscopy ,GEMS & precious stones ,JADE ,PEARLS ,GEMOLOGY - Abstract
Being nondestructive and requiring short measurement times, a low amount of material, and no sample preparation, Raman spectroscopy is used for routine investigation in the study of gemstone inclusions and treatments and for the characterization of mounted gems. In this work, a review of the use of laboratory Raman and micro-Raman spectrometers and of portable Raman systems in the gemology field is given, focusing on gem identification and on the evaluation of the composition, provenance, and genesis of gems. Many examples are shown of the use of Raman spectroscopy as a tool for the identification of imitations, synthetic gems, and enhancement treatments in natural gemstones. Some recent developments are described, with particular attention being given to the semiprecious stone jade and to two important organic materials used in jewelry, i.e., pearls and corals. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
29. A Fast Retrieval of Cloud Parameters Using a Triplet of Wavelengths of Oxygen Dimer Band around 477 nm
- Author
-
Kwang-Mog Lee, Haklim Choi, Xiong Liu, Jhoon Kim, Jongjin Seo, and G. Gonzalez Abad
- Subjects
cloud fraction ,Physics ,FRESCO ,oxygen dimer ,010504 meteorology & atmospheric sciences ,Spectrometer ,Science ,Cloud top ,Cloud fraction ,fast retrieval ,cloud top pressure ,GEMS ,VLIDORT ,01 natural sciences ,Computational physics ,Wavelength ,Optical path ,0103 physical sciences ,Radiance ,Radiative transfer ,General Earth and Planetary Sciences ,Absorption (electromagnetic radiation) ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences - Abstract
Clouds act as a major reflector that changes the amount of sunlight reflected to space. Change in radiance intensity due to the presence of clouds interrupts the retrieval of trace gas or aerosol properties from satellite data. In this paper, we developed a fast and robust algorithm, named the fast cloud retrieval algorithm, using a triplet of wavelengths (469, 477, and 485 nm) of the O2–O2 absorption band around 477 nm (CLDTO4) to derive the cloud information such as cloud top pressure (CTP) and cloud fraction (CF) for the Geostationary Environment Monitoring Spectrometer (GEMS). The novel algorithm is based on the fact that the difference in the optical path through which light passes with regard to the altitude of clouds causes a change in radiance due to the absorption of O2–O2 at the three selected wavelengths. To reduce the time required for algorithm calculations, the look-up table (LUT) method was applied. The LUT was pre-constructed for various conditions of geometry using Vectorized Linearized Discrete Ordinate Radiative Transfer (VLIDORT) to consider the polarization of the scattered light. The GEMS was launched in February 2020, but the observed data of GEMS have not yet been widely released. To evaluate the performance of the algorithm, the retrieved CTP and CF using observational data from the Global Ozone Monitoring Experiment-2 (GOME-2), which cover the spectral range of GEMS, were compared with the results of the Fast Retrieval Scheme for Clouds from the Oxygen A band (FRESCO) algorithm, which is based on the O2 A-band. There was good agreement between the results, despite small discrepancies for low clouds.
- Published
- 2021
30. Molecular Characterisation of Cryptosporidium spp. in Mozambican Children Younger than 5 Years Enrolled in a Matched Case-Control Study on the Aetiology of Diarrhoeal Disease.
- Author
-
Messa Jr., Augusto, Köster, Pamela C., Garrine, Marcelino, Nhampossa, Tacilta, Massora, Sérgio, Cossa, Anélsio, Bassat, Quique, Kotloff, Karen, Levine, Myron M., Alonso, Pedro L., Carmena, David, and Mandomando, Inácio
- Subjects
ETIOLOGY of diseases ,CRYPTOSPORIDIUM ,CRYPTOSPORIDIOSIS ,COGNITION disorders ,ANIMAL species ,MOLECULAR epidemiology - Abstract
Cryptosporidium is a leading cause of childhood diarrhoea and associated physical and cognitive impairment in low-resource settings. Cryptosporidium-positive faecal samples (n = 190) from children aged ≤ 5 years enrolled in the Global Enteric Multicenter Study (GEMS) in Mozambique detected by ELISA (11.5%, 430/3754) were successfully PCR-amplified and sequenced at the gp60 or ssu rRNA loci for species determination and genotyping. Three Cryptosporidium species including C. hominis (72.6%, 138/190), C. parvum (22.6%, 43/190), and C. meleagridis (4.2%, 8/190) were detected. Children ≤ 23 months were more exposed to Cryptosporidium spp. infections than older children. Both C. hominis and C. parvum were more prevalent among children with diarrhoeal disease compared to those children without it (47.6% vs. 33.3%, p = 0.007 and 23.7% vs. 11.8%, p = 0.014, respectively). A high intra-species genetic variability was observed within C. hominis (subtype families Ia, Ib, Id, Ie, and If) and C. parvum (subtype families IIb, IIc, IIe, and IIi) but not within C. meleagridis (subtype family IIIb). No association between Cryptosporidium species/genotypes and child's age was demonstrated. The predominance of C. hominis and C. parvum IIc suggests that most of the Cryptosporidium infections were anthroponotically transmitted, although zoonotic transmission events also occurred at an unknown rate. The role of livestock, poultry, and other domestic animal species as sources of environmental contamination and human cryptosporidiosis should be investigated in further molecular epidemiological studies in Mozambique. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
31. The New Potential of Deep Convective Clouds as a Calibration Target for a Geostationary UV/VIS Hyperspectral Spectrometer
- Author
-
Mina Kang, Myoung Hwan Ahn, and Yeeun Lee
- Subjects
010504 meteorology & atmospheric sciences ,Physics::Instrumentation and Detectors ,Science ,0211 other engineering and technologies ,TROPOMI ,02 engineering and technology ,01 natural sciences ,deep convective cloud ,vicarious calibration ,Calibration ,Image resolution ,Physics::Atmospheric and Oceanic Physics ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Remote sensing ,Ozone Monitoring Instrument ,Spectrometer ,hyperspectral data ,OMI ,Hyperspectral imaging ,UV ,VIS ,Temporal resolution ,Geostationary orbit ,General Earth and Planetary Sciences ,Environmental science ,Cirrus ,GEMS - Abstract
As one of geostationary earth orbit constellation for environmental monitoring over the next decade, the Geostationary Environment Monitoring Spectrometer (GEMS) has been designed to observe the Asia-Pacific region to provide information on atmospheric chemicals, aerosols, and cloud properties. In order to continuously monitor sensor performance after its launch in early 2020, we suggest in this paper deep convective clouds (DCCs) as a possible target for the vicarious calibration of the GEMS, the first ultraviolet and visible hyperspectral sensor onboard a geostationary satellite. The Tropospheric Monitoring Instrument (TROPOMI) and the Ozone Monitoring Instrument (OMI) are used as a proxy for GEMS, and a conventional DCC-detection approach applying a thermal threshold test is used for DCC detection based on collocations with the Advanced Himawari Imager (AHI) onboard the Himawari-8 geostationary satellite. DCCs are frequently detected over the GEMS observation area at an average of over 200 pixels within a single observation scene. Considering the spatial resolution of the GEMS (3.5 × 8 km2), which is similar to the TROPOMI and its temporal resolution (eight times a day), the availability of DCCs is expected to be sufficient for the vicarious calibration of the GEMS. Inspection of the DCC reflectivity spectra estimated from OMI and TROPOMI data also shows promising results. The estimated DCC spectra are in good agreement within a known uncertainty range with comparable spectral features even with different observation geometries and sensor characteristics. When DCC detection is improved further by applying both visible and infrared tests, the variability of DCC reflectivity from TROPOMI data is reduced from 10% to 5%. This is mainly due to the efficient screening out of cold, thin cirrus clouds in the visible test and of bright, warm clouds in the infrared test. Precise DCC detection is also expected to contribute to the accurate characterization of cloud reflectivity, which will be investigated further in future research.
- Published
- 2020
32. Nikolo intaglio kao primjer značenja i važnosti dragoga kamena i njegove imitacije u staklu u antičkom periodu
- Author
-
Ivanka Ribarević-Nikolić
- Subjects
History ,Archeology ,gemologija ,arheologija ,nikolo ,dragi kamen ,stakleni intaglio ,gemmology ,archaeology ,nicolo ,gems ,glass intaglio - Abstract
Interdisciplinarnim istraživanjem, prvenstveno gemologije i arheologije na primjeru nikolo intaglija, ukazujemo na važnost dragoga kamena u antičkom periodu. Ujedno pratimo pojavnost imitacije u staklu nikolo intaglija i ukazujemo na moguće simboličko značenje imitacije., An interdisciplinary approach to the research of gemmology and archaeology has discovered a variety of information which simultaneously enrich the achievements of both disciplines. This paper highlights the importance of gems, especially in the Ancient World. From the gemmological aspect, a gem is natural if all of its natural features are preserved. Also, we describe gems with some of their original characteristics modified in certain treatments, most frequently the change of natural gem colour. Furthermore, we show how the imitations of gems are created with the use of natural or artificial materials. Nicolo is taken as an example. It is onyx, of specific bluish white upper layer and very dark brown or black lower layer. It is assumed that nicolo can be identified with the antique stone that Pliny the Elder called aegyptilla. Nicolo became popular stone for intaglio carving at the time of the Empire, especially since the Augustan era, and was continuously used until the late antiquity. At the same time, imitations of nicolo intaglio in glass were produced which, with the colour (light blue and black combined) and the shape, followed the changes of the cutting techniques of the original intaglio. The main changes of shape were shown in a variety of nicolo cutting methods, with one or both colours of the stone being visible on the surface. When the edges are cut at right angles, only the upper blue layer of stone is visible on the surface of the intaglio. Nicolo intaglio with the edges cut at acute angles can contrast the colours of both layers of the stone. As a result, the blue colour in the centre, always containing a picture, is surrounded by darker colours of the lower layer of the stone. Glass imitations of nicolo intaglio were found in the combinations of light blue and dark blue. Dark blue colour is not typical for natural nicolo or natural onyx in general. With the "sugar-acid" treatment, the onyx of grey and white colours was changed to resemble nicolo onyx, and probably this atypical colour combination of different blue shades was imitated in glass. It is believed that precious stone has a supernatural protective power manifested in its specific substance and its invisible energy. The long continuity of making and using nicolo intaglio and their imitations points to the importance of this precious stone as well as its imitation. We would like to point out that an imitation, same as natural precious stone, possesses the equal supernatural power. A philosophical concept of sympatheia was taken as an example, according to which "likeness produces similarity", meaning that the objects which were once in contact continue to impact each other at a distance, even though physical contact was interrupted. Thus, according to the philosophical concept of sympatheia, the glass imitation shows resemblance, i.e. a glass intaglio that imitates nicolo, is similar to nicolo stone. The picture message which is always present in intaglio, was obtained by imprint of an original precious stone. Thus, the original precious stone, together with the picture, was in contact with a medium used to produce glass intaglio, and therefore, even at distance and indirectly, conveys the acting power of the original substance. Consequently, the imitation possesses all the invisible energy features as the original. Certainly, this assumption requires further research, primarily based on the gemmological analysis of stylistic and chronological typology of the museum artefacts and the identification of precious stone imitations, with equally important information from written sources as well as philosophical and anthropological studies.
- Published
- 2018
33. Use of the EDXRF technique in the analysis of semiprecious Brazilian Gems
- Author
-
Rezier, Ayxa Nara de Souza, Assis, Joaquim Teixeira de, Carvalho, Gil de, Brunetti, Antônio, Oliveira, Carlos Ivan Ribeiro de, and Geraldes, Mauro Cesar
- Subjects
Gemas (Mineralogia) ,Pedras preciosas ,Characterization ,XRF ,ENGENHARIAS::ENGENHARIA NUCLEAR::APLICACOES DE RADIOISOTOPOS [CNPQ] ,X-Ray ,Caracterização ,Fluorescência ,Fluorescence ,Gems ,Raios X - Abstract
Submitted by Boris Flegr (boris@uerj.br) on 2021-01-05T18:31:13Z No. of bitstreams: 1 Dissertacao_AyxaNaraDeSouzaRezier.pdf: 2854218 bytes, checksum: 3fc24ffc0121d416e9ddf687c54c0661 (MD5) Made available in DSpace on 2021-01-05T18:31:13Z (GMT). No. of bitstreams: 1 Dissertacao_AyxaNaraDeSouzaRezier.pdf: 2854218 bytes, checksum: 3fc24ffc0121d416e9ddf687c54c0661 (MD5) Previous issue date: 2017-10-16 Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro Brazil is one of the largest and most important producers of gemstones on the planet, besides being distinguished by the quality and gemological variety. It has a wide and diversified production scenario covering mainly the foreign market, with the main consumer sectors being jewelery and the stoning industry, as well as a wide range of use in the electronics, steel, electrical, optics, instrumentation, handicrafts and agriculture industries. With the technological advance, mineralogical studies and research are extremely important for the understanding of physicochemical properties, identification and chemical and structural characterization of gemstones, since the use of gemstones in industry is a function of their elemental composition. In the developed project, elemental characterizations were performed in samples of some Brazilian gems using the Energy Dispersion X-Ray Fluorescence technique (EDXRF). The qualitative determination of elements had as main objective to analyze and verify possible presence of elements and impurities that are not part of the elemental composition belonging to the class of silicates and carbonates. The analyzes were performed on two different portable devices, the Amptek mini mini-XRF and the Bruker AR ARTAX 200, with data acquisition and analysis programs from these manufacturers. The minerals analyzed were: Amethyst, Orange Calcite, Onyx, Jade, Citrine, Colorless Quartz, Milky Quartz, Blue Quartz, Green Quartz and Pink Quartz. The presence of metallic ions, in particular transition metals such as Ti, Cr, Mn, Fe, Co, Ni and Cu were verified. The possible reasons for the existence of these ions are discussed in the paper. The data of elemental analyzes by EDXRF indicate coherence in the elemental compositions obtained with the two portable systems of XRF and it is observed that both present efficiency in relation to the elements analyzed, indicating that the technique can be used to assist in the development of mineralogical studies. O Brasil é um dos maiores e mais importantes produtores de gemas do planeta, além de destacar-se pela qualidade e variedade gemológica. Possui um amplo e diversificado cenário produtivo abrangendo principalmente o mercado externo, tendo como principais setores de consumo a joalheria e a indústria de lapidação, além de uma ampla gama de utilização nas indústrias eletrônica, siderúrgica, elétrica, óptica, instrumentação, artesanato e agricultura. Com o avanço tecnológico, os estudos e pesquisas mineralógicos são de extrema importância para o entendimento das propriedades físico-químicas, a identificação e a caracterização química e estrutural das gemas, pois o emprego das gemas na indústria é função da sua composição elementar. No projeto desenvolvido, foram realizadas caracterizações elementares em amostras de algumas gemas brasileiras mediante a utilização da técnica de Fluorescência de Raios X por Dispersão em Energia (EDXRF). A determinação qualitativa de elementos teve como objetivo principal de analisar e verificar possíveis presenças de elementos e impurezas que não fazem parte da composição elementar pertencente à classe dos silicatos e carbonatos. As análises foram realizadas em dois equipamentos portáteis diferentes, o mini-XRF da Amptek® e o ARTAX 200 da Bruker®, com programas de aquisição e análise dos dados desses fabricantes. Os minerais analisados foram: Ametista, Calcita laranja, Ônix, Jade, Citrino, Quartzo incolor, Quartzo leitoso, Quartzo azul, Quartzo verde e Quartzo rosa. Verificou-se a existência de íons metálicos, em especial metais de transição como Ti, Cr, Mn, Fe, Co, Ni e Cu. As possíveis razões para a existência destes íons são discutidas no trabalho. Os dados das análises elementares por EDXRF indicam coerência nas composições elementares obtidos com os dois sistemas portáteis de XRF e observa-se que ambos apresentam eficiência em relação aos elementos analisados, indicando que a técnica pode ser utilizada para auxiliar no desenvolvimento de estudos mineralógicos.
- Published
- 2017
34. Coilin levels and modifications influence artificial reporter splicing
- Author
-
Whittom, A. A., Xu, H., and Hebert, M. D.
- Published
- 2008
- Full Text
- View/download PDF
35. Association between Non-Typhoidal Salmonella Infection and Growth in Children under 5 Years of Age: Analyzing Data from the Global Enteric Multicenter Study.
- Author
-
Das, Rina, Haque, Md. Ahshanul, Chisti, Mohammod Jobayer, Faruque, Abu Sayed Golam, Ahmed, Tahmeed, and Alaedini, Armin
- Abstract
Non-typhoidal Salmonella (NTS) is one of the less focused on infections and is often associated with faulty child nutrition in the developing world. This study aimed to evaluate the association of NTS infection with growth faltering among children under the age of five. We analyzed data from 378 fecal NTS positive children with both moderate-to-severe diarrhea (MSD) and asymptomatic infection from the seven countries of South Asia and sub-Saharan Africa during enrolment and on day 60 follow up in the Global Enteric Multicenter Study (GEMS) for the period of December 2007 to March 2011. Children not associated with fecal NTS (n = 1134) were randomly selected from the same dataset (1:3 ratio) as a comparison group. The association between an explanatory variable and the outcome variable was longitudinally tested using generalized estimating equations (GEE), where the dependent variables were height-for-age (HAZ), weight-for-age (WAZ), and weight-for-height (WHZ) z-score, and the independent variable was the presence of fecal NTS. The GEE multivariable model identified a negative association between fecal NTS and WAZ (coefficient: −0.19; 95% CI (confidence interval): −0.33, −0.04, and p value = 0.010), WHZ (coef: −0.19; 95% CI: −0.34, −0.05, and p value = 0.007), and HAZ (coef: −0.13; 95% CI: −0.27, −0.01, and p value = 0.073) after adjusting for age, gender, diarrhea, breastfeeding status, mothers' education, number of children under the age of five, household size by the number of people regularly sleep at the home, handwashing practice, source of drinking water, wealth index, presence of co-pathogens, comorbidity, and study sites. In the GEMS, where children were followed during 50–90 days of enrolment, the presence of fecal NTS harmed the child's anthropometric outcomes. Minimizing potential exposure to NTS is needed to curb worsening child undernutrition. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
36. Investing in Diamonds
- Author
-
Luc Renneboog, Department of Finance, and Research Group: Finance
- Subjects
Diamonds ,Hedonic regressions ,jel:Z11 ,Auctions ,Financial economics ,Bond ,Sharpe ratio ,Alternative investments ,Diversification (finance) ,Geology ,Real estate ,jel:G12 ,jel:Q3 ,Geotechnical Engineering and Engineering Geology ,jel:G11 ,Hardware and Architecture ,Economics ,Luxury goods ,Portfolio ,Alternative investment ,Hedonic regression ,Auctions, Diamonds, Gems, Hedonic regressions, Luxury goods, Alternative investments ,Stock (geology) ,Gems - Abstract
This paper examines the risk-return characteristics of investment grade gems (white diamonds, colored diamonds and other types of gems including sapphires, rubies, and emeralds). The transactions are coming from gem auctions and span the period 1999-2012. Over our time frame, the annual nominal USD returns for white and colored diamonds amount to 8.1% and 7.4%, respectively, or 5.5% and 4.8% in real terms. For a Euro investor, the returns on white and colored diamonds are about 1.3% lower than for a USD investors but the Euro returns still beat inflation by 3.5% annually. The returns for Other Gem types (rubies, emeralds and sapphires) are more volatile and somewhat lower (4.5% annual nominal returns and 2.1% in annual real terms). Applying the hedonic regression method to the data set of auction transactions of investment grade diamonds, we are able to explain more than 95% of their price variation in white diamonds. Although the diamond returns since 1999 have been below those on gold, both white and colored diamonds have significantly outperformed the US and European stock markets, US and European real estate, US government bonds, as well as European government and corporate bonds. The reward-to-risk (Sharpe ratio) of white diamonds is very close to that of US corporate government bonds. The highest Sharpe ratio (by far) over the past 14 years was the one on gold. Still, in times of crisis investments in diamonds have shown an attractive risk-return tradeoff. In spite of a small positive correlation between the diamond and the equity markets, adding diamonds to an equity portfolio still have some diversification advantages.
- Published
- 2015
37. Spatio-Temporal Variability of Aerosol Optical Depth, Total Ozone and NO2 Over East Asia: Strategy for the Validation to the GEMS Scientific Products.
- Author
-
Park, Sang Seo, Kim, Sang-Woo, Song, Chang-Keun, Park, Jong-Uk, and Bae, Kang-Ho
- Subjects
OPTICAL depth (Astrophysics) ,OZONE ,AEROSOLS ,SPATIO-temporal variation ,POLLUTANTS ,TROPOSPHERIC ozone ,OZONE layer - Abstract
In this study, the spatio-temporal variability of aerosol optical depth (AOD), total column ozone (TCO), and total column NO
2 (TCN) was identified over East Asia using long-term datasets from ground-based and satellite observations. Based on the statistical results, optimized spatio-temporal ranges for the validation study were determined with respect to the target materials. To determine both spatial and temporal ranges for the validation study, we confirmed that the observed datasets can be statistically considered as the same quantity within the ranges. Based on the thresholds of R2 >0.95 (temporal) and R>0.95 (spatial), the basic ranges for spatial and temporal scales for AOD validation was within 30 km and 30 min, respectively. Furthermore, the spatial scales for AOD validation showed seasonal variation, which expanded the range to 40 km in summer and autumn. Because of the seasonal change of latitudinal gradient of the TCO, the seasonal variation of the north-south range is a considerable point. For the TCO validation, the north-south range is varied from 0.87° in spring to 1.05° in summer. The spatio-temporal range for TCN validation was 20 min (temporal) and 20–50 km (spatial). However, the nearest value of satellite data was used in the validation because the spatio-temporal variation of TCN is large in summer and autumn. Estimation of the spatio-temporal variability for respective pollutants may contribute to improving the validation of satellite products. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
38. Global Embeddings of BTZ and Schwarzschild-ADS Type Black Holes in a Flat Space.
- Author
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Sheykin, Anton, Solovyev, Dmitry, and Paston, Sergey
- Subjects
BLACK holes ,EMBEDDINGS (Mathematics) ,COSMOLOGICAL constant ,SPACE - Abstract
We study the problem of construction of global isometric embedding for spherically symmetric black holes with negative cosmological constant in various dimensions. Firstly, we show that there is no such embedding for 4D RN-AdS black hole in 6D flat ambient space, completing the classification which we started earlier. Then we construct an explicit embedding of non-spinning BTZ black hole in 6D flat ambient space. Using this embedding as an anzats, we then construct a global explicit embedding of d-dimensional Schwarzschild-AdS black hole in a flat (d + 3) -dimensional ambient space. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
39. Household Costs of Diarrhea by Etiology in 7 Countries, The Global Enterics Mulitcenter Study (GEMS).
- Author
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Zimmermann, Marita, Kotloff, Karen, Nasrin, Dilruba, Roose, Anna, Levine, Myron M, Rheingans, Richard, Farag, Tamar, Walker, Damian, and Pecenka, Clint
- Subjects
ETIOLOGY of diseases ,DIARRHEA ,HOUSEHOLDS ,COST ,CAMPYLOBACTER jejuni - Published
- 2019
- Full Text
- View/download PDF
40. The Returns on Investment Grade Diamonds
- Author
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Renneboog, L.D.R., Research Group: Finance, and Department of Finance
- Subjects
alternative investments ,diamonds ,auctions ,luxury goods ,hedonic regressions ,gems - Abstract
This paper examines the risk-return characteristics of investment grade gems (white diamonds, colored diamonds and other types of gems including sapphires, rubies, and emeralds). The transactions are coming from gem auctions and span the period 1999-2012. Over our time frame, the annual nominal USD returns for white and colored diamonds amount to 8.1% and 7.4%, respectively, or 5.5% and 4.8% in real terms. For a Euro investor, the returns on white and colored diamonds are about 1.3% lower than for a USD investors but the Euro returns still beat inflation by 3.5% annually. The returns for Other Gem types (rubies, emeralds and sapphires) are more volatile and somewhat lower (4.5% annual nominal returns and 2.1% in annual real terms). Applying the hedonic regression method to the data set of auction transactions of investment grade diamonds, we are able to explain more than 95% of their price variation in white diamonds. Although the diamond returns since 1999 have been below those on gold, both white and colored diamonds have significantly outperformed the US and European stock markets, US and European real estate, US government bonds, as well as European government and corporate bonds. The reward-to-risk (Sharpe ratio) of white diamonds is very close to that of US corporate government bonds. The highest Sharpe ratio (by far) over the past 14 years was the one on gold. Still, in times of crisis investments in diamonds have shown an attractive risk-return tradeoff. In spite of a small positive correlation between the diamond and the equity markets, adding diamonds to an equity portfolio still have some diversification advantages.
- Published
- 2013
41. The Returns on Investment Grade Diamonds
- Subjects
alternative investments ,diamonds ,auctions ,luxury goods ,hedonic regressions ,gems - Abstract
This paper examines the risk-return characteristics of investment grade gems (white diamonds, colored diamonds and other types of gems including sapphires, rubies, and emeralds). The transactions are coming from gem auctions and span the period 1999-2012. Over our time frame, the annual nominal USD returns for white and colored diamonds amount to 8.1% and 7.4%, respectively, or 5.5% and 4.8% in real terms. For a Euro investor, the returns on white and colored diamonds are about 1.3% lower than for a USD investors but the Euro returns still beat inflation by 3.5% annually. The returns for Other Gem types (rubies, emeralds and sapphires) are more volatile and somewhat lower (4.5% annual nominal returns and 2.1% in annual real terms). Applying the hedonic regression method to the data set of auction transactions of investment grade diamonds, we are able to explain more than 95% of their price variation in white diamonds. Although the diamond returns since 1999 have been below those on gold, both white and colored diamonds have significantly outperformed the US and European stock markets, US and European real estate, US government bonds, as well as European government and corporate bonds. The reward-to-risk (Sharpe ratio) of white diamonds is very close to that of US corporate government bonds. The highest Sharpe ratio (by far) over the past 14 years was the one on gold. Still, in times of crisis investments in diamonds have shown an attractive risk-return tradeoff. In spite of a small positive correlation between the diamond and the equity markets, adding diamonds to an equity portfolio still have some diversification advantages.
- Published
- 2013
42. Trace gas/aerosol boundary concentrations and their impacts on continental-scale AQMEII modeling domains
- Author
-
Shawn J. Roselle, Johannes Flemming, Kenneth L. Schere, Bertrand Bessagnet, Charles Chemel, Stefano Galmarini, Ranjeet S. Sokhi, Rong-Ming Hu, S. Trivikrama Rao, Robert Vautard, Augustin Colette, Frédérik Meleux, Christian Hogrefe, Rohit Mathur, ORD, National Exposure Research Laboratory, Atmospheric Modeling and Analysis Division, US Environmental Protection Agency (EPA), European Centre for Medium-Range Weather Forecasts (ECMWF), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Extrèmes : Statistiques, Impacts et Régionalisation (ESTIMR), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre for Atmospheric and Instrumentation Research [Hatfield] (CAIR), University of Hertfordshire [Hatfield] (UH), Institut National de l'Environnement Industriel et des Risques (INERIS), Bureau of Air Quality Analysis and Research, New York State Department of Environmental Conservation (NY DEC), JRC Institute for Environment and Sustainability (IES), European Commission - Joint Research Centre [Ispra] (JRC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Atmospheric Science ,010504 meteorology & atmospheric sciences ,Meteorology ,Mesoscale meteorology ,Boundary (topology) ,AQMEII ,010501 environmental sciences ,01 natural sciences ,Trace gas ,Aerosol ,Latitude ,MODEL EVALUATION ,13. Climate action ,[SDE]Environmental Sciences ,Environmental science ,Satellite ,AIR QUALITY MODELING ,Longitude ,BOUNDARY CONCENTRATIONS ,Air quality index ,GEMS ,0105 earth and related environmental sciences ,General Environmental Science - Abstract
International audience; Over twenty modeling groups are participating in the Air Quality Model Evaluation International Initiative (AQMEII) in which a variety of mesoscale photochemical and aerosol air quality modeling systems are being applied to continental-scale domains in North America and Europe for 2006 full-year simulations for model inter-comparisons and evaluations. To better understand the reasons for differences in model results among these participating groups, each group was asked to use the same source of emissions and boundary concentration data for their simulations. This paper describes the development and application of the boundary concentration data for this AQMEII modeling exercise. The European project known as GEMS (Global and regional Earth-system Monitoring using Satellite and in-situ data) has produced global-scale re-analyses of air quality for several years, including 2006 (http://gems.ecmwf.int). The GEMS trace gas and aerosol data were made available at 3-hourly intervals on a regular latitude/longitude grid of approximately 1.9° resolution within 2 'cut-outs' from the global model domain. One cut-out was centered over North America and the other over Europe, covering sufficient spatial domain for each modeling group to extract the necessary time- and space-varying (horizontal and vertical) concentrations for their mesoscale model boundaries. Examples of the impact of these boundary concentrations on the AQMEII continental simulations are presented to quantify the sensitivity of the simulations to boundary concentrations. In addition, some participating groups were not able to use the GEMS data and instead relied upon other sources for their boundary concentration specifications. These are noted, and the contrasting impacts of other data sources for boundary data are presented. How one specifies four-dimensional boundary concentrations for mesoscale air quality simulations can have a profound impact on the model results, and hence, this aspect of data preparation must be performed with considerable care.
- Published
- 2012
43. Hard Assets: The Returns on Rare Diamonds and Gems
- Author
-
Renneboog, L.D.R., Spaenjers, C., Research Group: Finance, and Department of Finance
- Subjects
Diamonds ,Hedonic regressions ,Auctions ,Alternative investments ,Gems - Abstract
This paper examines the investment performance of diamonds and other gems (sapphires, rubies, and emeralds) over the period 1999-2010, using a novel data set of auction transactions. Between 1999 and 2010, the annualized real USD returns for white and colored diamonds equaled 6.4% and 2.9%, respectively. Since 2003, the returns were 10.0%, 5.5%, and 6.8% for white diamonds, colored diamonds, and other gems, respectively. Both white and colored diamonds outperformed the stock market over our time frame. Nevertheless, gem returns are positively correlated with stock market returns, suggesting the existence of stock market wealth effects.
- Published
- 2011
44. Hard Assets
- Subjects
Diamonds ,Hedonic regressions ,Auctions ,Alternative investments ,Gems - Abstract
This paper examines the investment performance of diamonds and other gems (sapphires, rubies, and emeralds) over the period 1999-2010, using a novel data set of auction transactions. Between 1999 and 2010, the annualized real USD returns for white and colored diamonds equaled 6.4% and 2.9%, respectively. Since 2003, the returns were 10.0%, 5.5%, and 6.8% for white diamonds, colored diamonds, and other gems, respectively. Both white and colored diamonds outperformed the stock market over our time frame. Nevertheless, gem returns are positively correlated with stock market returns, suggesting the existence of stock market wealth effects.
- Published
- 2011
45. Inverse adverse selection: the market for gems
- Author
-
Dari-Mattiacci, Giuseppe, Onderstal, Sander, Parisi, Francesco, Amsterdam Center for Law and Economics (FdR, FEB), Markets & Organizations (ASE, FEB), Experimental and Political Economics / CREED (ASE, FEB), ACLE (FdR), and ABS Other Research (FEB)
- Subjects
Lemons ,Adverse selection ,Asymmetric information ,Adverse Selektion ,K12 ,Auction ,D82 ,Asymmetrische Information ,ddc:330 ,Auktionstheorie ,ComputingMilieux_COMPUTERSANDSOCIETY ,D86 ,Gems ,D44 - Abstract
This paper studies markets plagued with asymmetric information on the quality of traded goods. In Akerlof's setting, sellers are better informed than buyers. In contrast, we examine cases where buyers are better informed than sellers. This creates an inverse adverse selection problem: The market tends to disappear from the bottom rather than from the top. In contrast to the traditional model, it is the high-value goods (gems) that are traded on the market, rather than the low-value goods (lemons). We investigate the consequences of this inverse adverse selection and its potential solutions. The uninformed buyer in a traditional market for lemons experiences the quality of the good he purchased; instead, the uninformed seller may never know the quality of the good that he sold. This renders the conventional legal and contractual solutions to the lemons problem often ineffective in the gems case. We further explore the theoretical and practical appeal of m arket, contractual, and legal solutions. Our results show that auctions (competition among many informed buyers) provide a solution to the inverse adverse selection problem.
- Published
- 2011
46. Reviving Historical Trade Routes: A Case Study of the Silk Route - Gateway to China.
- Author
-
Wizarat, Talat A.
- Subjects
SILK Road ,TRADE routes ,POVERTY reduction ,CASE studies ,ECONOMIC development - Abstract
Ancient trade routes played an important role in promotion of economic ties and cultural linkages. Some of these routes cannot be revived due to technological and political changes. However, Pakistan and Peoples Republic of China (PRC) have made bold efforts to revive the Silk Route. The revival will reduce the distance between PRC and its markets in Europe, Middle East and Africa. Pakistan also stands to prosper from this scheme. [ABSTRACT FROM AUTHOR]
- Published
- 2015
47. Mineral Shop Offers a Mine of Curious Fun
- Author
-
Libov, Charlotte
- Subjects
Gems ,Precious stones - Abstract
LEAD: WITH plastic miner's helmets atop their heads, 7-year-old Robby Brown and his brother, Danny, , age 6, sorted through their little paper sacks, seeking out glittering bits of amethyst […]
- Published
- 1989
48. Le serpent léontocéphale Chnoubis et la magie de l'époque romaine impériale
- Author
-
Dasen, Véronique and Nagy, Árpád M.
- Published
- 2012
- Full Text
- View/download PDF
49. Kushi-Ya, Nottingham: 'A blissfully good place' -- restaurant review; Tucked away up in the rafters, this hidden gem in Nottingham reaches dizzying heights with its joyous Japanese food
- Subjects
Restaurants -- Restaurant reviews ,Gems ,Precious stones ,General interest ,News, opinion and commentary - Abstract
Byline: Jay Rayner Kushi-Ya, 1A Cannon Court, Long Row W, Nottingham NG1 6JE. No lunchtime bookings. Snacks £3.50, plates and skewers £5.50-£14, desserts £5-£7, wines from £24 It would be [...]
- Published
- 2022
50. Diamond thief must pay back £244 after record £4.2m heist; Lulu Lakatos stole from Mayfair jeweller by replacing gems with pebbles in UK's most expensive theft of its kind
- Subjects
Theft ,Jewelers ,Jewelry industry ,Gems ,Precious stones ,Conspiracy ,News, opinion and commentary - Abstract
Byline: Tobi Thomas A woman who stole £4.2m worth of diamonds by swapping them for pebbles has been ordered to pay back less than £250. Lulu Lakatos, 60, is serving [...]
- Published
- 2022
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