45,016 research outputs found
Magnetic properties and 57Fe Mössbauer spectroscopy of Mediterranean prehistoric obsidians for provenance studies
No full textSamples from the Mediterranean source-islands: Gyali, Lipari, Melos, Palmarola, Pantelleria and Sardinia (Monte Arci) had their 57Fe M€ossbauer spectra and magnetizations measured. The saturation magnetization (Ms) depends on the island of provenance and it reaches a maximum 0.3 emu/g for Palmarola obsidians, indicating a larger magnetic phase content. The coercive forces (Hc) range from 46 to 372 Oe for respectively samples from Pantelleria and
Palmarola islands. Our analyses show that in a Mr=Ms vs. Hc=Hm plot the data points accumulate in areas that depend on obsidian provenance (Mr, remanent magnetization; Hm, maximum applied field). The M€ossbauer spectra are mainly
composed of broad asymmetric doublets, which were fitted assuming two Fe2þ and one Fe3þ sites. In addition, the
obsidians of Melos and Palmarola present a magnetic component attributed to magnetite and/or hematite. Binary diagrams comparing different Mossbauer hyperfine parameters for the Fe3þ and Fe2þ species gave indications of similarities and differences between obsidians of different origins. Since this kind of plot does not give an unambiguous characterization of samples from each island, a detailed analysis of the M€ossbauer results is in progress using statistical method of clustering analysis as has been shown by Scorzelli et al. [Comptes Rendus Acad. Sci., Serie II, 332 (2001) 769] and Poupeau et al. [IAOS Bull. 28 (2001) 2] in previous studies
SEEA and Ecosystem Services Accounting: A Promising Framework for Territorial Governance Innovation
No full textES rapidly was adopted by quantitative geographers and urban planners as an effective tool to deliver reliable spatial analysis on natural capital and its interaction with citizens and economic ecosystem. Although several relevant applications of ES in planning have been realised, it is still difficult to find a common agreement on how to adopt ES as a standard planning support system. Through a literature review this research aims to highlight how monetizing ecosystem services could be effectively integrated in territorial management practices. The System of Environmental-Economic Accounting (SEEA) framework was identified as a promising tool for this purpose according to its analytical structure based on the integration of national budget, spatial analytics based on ES, and social information characterizing the groups of beneficiaries. It represents an international accounting tools for natural capital appraisal aimed at supporting a holistic decision-making process adopted by UN. In particular, SEEA aims to provide accounting over time to measure the health of the environment, the environment’s contribution to the economy, and the impacts of economic activities on the environment. The research aims to highlight the challenges and opportunities that arise from implementing SEEA in urban planning, providing a critical analysis of the value of ecosystem services with the goal of promoting sustainable practices and nature conservation
Spatial Multi-criteria Analysis for Identifying Suitable Locations for Green Hydrogen Infrastructure
No full textThe paper proposes a Spatial Multi-Criteria Analysis for identifying suitable locations for green hydrogen infrastructure. The production and use of hydrogen as a renewable energy carrier can play a critical role in reducing carbon footprint and increasing energy security in cities worldwide. The approach considers multiple criteria, such as demand, accessibility, environmental impact, and cost, to identify optimal locations for hydrogen production, storage, and distribution facilities. The GIS component enables spatial analysis, allowing visualization and analysis of spatial relationships between potential locations and other relevant factors. The research claims that green hydrogen can significantly improve energy resilience and transform energy systems. The method is applied to a case study, an energy-intensive industry in the city of Potenza (Italy). The result is the map identifying suitable areas where hydrogen production facilities can be located. The approach suggests that urban planners, decision-makers, and stakeholders develop and use green hydrogen as a sustainable energy source
Letter from Arno B. Cammerer to J. R. Eakin
No full textLetter from Arno B. Cammerer to J. R. Eakin describing the procedure for purchasing Bright Angel Trail
Real time elastosonography in the diagnosis of prostate cancer
No full textTo assess the diagnostic gain of transrectal real time elastography(RTE) compared to transrectal B mode ultrasonography (US) in the detection of tumors in patients suspected of having prostate cancer. Eighty four patients suspected of having prostate cancer on the basis of clinical and biochemical evaluation underwent transrectal US, RRTE and transperineal prostate biopsiy.
RTE is a valid addition to B mode US, and RTE reached a higher accuracy than B mode US in the evaluation of the peripheral zone of the prostate gland and in the selection of appropriate biopsy site
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Iron-nickel superstructure in metal particles of Alfianello meteorite
No full textWe report on Mössbauer spectroscopy in metal particles of the Alfianello meteorite. The FeNi 50-50 ordered phase (tetrataenite) was detected in coexistence with a high proportion of the corresponding disordered phase. The order-disorder process is discussed in terms of shock events. © 1994 J.C. Baltzer AG, Science Publishers
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