1,395 research outputs found
The Polychrome Sinopia of Roman Mosaic at Lod (Israel): Pigments Characterization and Microstratigraphic Study
This paper presents the results of the archaeometric study on the pigments and the painting techniques used to produce the polichrome sinopia found under the tesserae of the Roman mosaic at Lod (Israel). The red, yellow, green and black paints, laying on the sovranucleus of the preparation mortar under the mosaic, were studied by polarised light microscopy on disperse pigments (PLM), reflected light microscopy (RLM), scanning electron microscopy (SEM) and X-ray powder diffraction (XRPD). The palette comprises red and yellow ochre, cinnabar, green earth and carbon black. The microstratigraphic analysis shows the presence of a carbonation layer including the pigment particles on the top of the mortars, indicating that the pigments were laid on a fresh mortar, according to a fresco technique.Department of Geosciences, University of Padova, Via Gradenigo 6, 35131 Padova, Italy, Art Conservation Department, Israel Antiquities Authority
Hydrochemical determination of source water contributions to Lake Lungo and Lake Ripasottile (central Italy)
Lake Lungo and Lake Ripasottile are two shallow (4-5 m) lakes located in the Rieti Basin, central Italy, that have been described previously as surface outcroppings of the groundwater table. In this work, the two lakes as well as springs and rivers that represent their potential source waters are characterized physio-chemically and isotopically, using a combination of environmental tracers. Temperature and pH were measured and water samples were analyzed for alkalinity, major ion concentration, and stable isotope (δ2H, δ18O, δ13C of dissolved inorganic carbon, and δ34S and δ18O of sulfate) composition. Chemical data were also investigated in terms of local meteorological data (air temperature, precipitation) to determine the sensitivity of lake parameters to changes in the surrounding environment. Groundwater represented by samples taken from Santa Susanna Spring was shown to be distinct with SO4 2- and Mg2+ content of 270 and 29 mg/L, respectively, and heavy sulfate isotopic composition (δ34S=15.2‰ and δ18O=10‰). Outflow from the Santa Susanna Spring enters Lake Ripasottile via a canal and both spring and lake water exhibits the same chemical distinctions and comparatively low seasonal variability. Major ion concentrations in Lake Lungo are similar to the Vicenna Riara Spring and are interpreted to represent the groundwater locally recharged within the plain. The δ13CDIC exhibit the same groupings as the other chemical parameters, providing supporting evidence of the source relationships. Lake Lungo exhibited exceptional ranges of δ13CDIC (±5‰) and δ2H, δ18O (±5 ‰ and ±7 ‰, respectively), attributed to sensitivity to seasonal changes. The hydrochemistry results, particularly major ion data, highlight how the two lakes, though geographically and morphologically similar, represent distinct hydrochemical facies. These data also show a different response in each lake to temperature and precipitation patterns in the basin that may be attributed to lake water retention time. The sensitivity of each lake to meteorological patterns can be used to understand the potential effects from long-term climate variability
Petrographic & microstratigraphic analysis of mortar-based building materials from the Temple of Venus, Pompeii.
Recipes for mortar-based building materials may change over time and differ in
various construction and restoration phases. They normally reflect craftsmen’s
knowledge, availability of raw materials, and also the importance of the building in
which they are found. The present research focuses on mortar-based materials from
several construction and renovation phases of the Temple of Venus, at Pompeii, Italy,
in order to identify any changes over time in production recipes
The relationship between pain induced autonomic arousal and perceived duration
Emotional distortions of the perceived duration of events are often explained in terms of increases and decreases in arousal. Whilst this explanation is theoretically plausible, there is a lack of evidence for a direct relationship between physiological arousal and perceived duration. The aim of the current study was to investigate whether physiological arousal, defined by autonomic nervous system (ANS) activity is directly related to perceived duration. In two experiments we measured skin conductance level (SCL) and high frequency heart rate variability (HF HRV) during verbal estimation tasks. In Experiment 1, participants estimated the duration of electro-cutaneous stimuli previously rated as inducing no pain, low pain and high pain. High intensity stimuli were perceived as lasting for longer than low intensity stimuli, and these changes in duration estimation were associated with changes in ANS activity. In Experiment 2, participants estimated the duration of a neutral visual stimulus whilst experiencing different intensities of background thermal pain (no pain, low pain, and high pain), to determine whether task-irrelevant arousal also affects time perception. Duration estimations for the neutral stimulus did not increase with pain intensity despite significant increases in SCL. Furthermore, there was no association between ANS activity and time estimation in Experiment 2. These findings suggest that the relationship between physiological arousal and time perception is more complex than previously described. Whilst physiological arousal can influence the perceived duration of events, it appears to have a greater capacity to do so when the to-be-timed stimulus is itself the source of arousal. ©American Psychological Association, 201
Mapping of stones and their deterioration forms : the Clock Tower, Venice (Italy)
The HYPERION EU project aims to develop a Decision Support System to improve resilience and sustainable reconstruction of historic areas faced with climate change and extreme events. In this context, Venice presents an outstanding example of urban and architectural complexity and richness. The mapping of the ornamental stones of the facade of the Venice Clock Tower (Torre dell'Orologio) and their deterioration patterns acts as a milestone on which to build the knowledge-acquisition process of the system as regards stone artefacts and their decay products. The Clock Tower is an early Renaissance building (1499) in Lombardesque style and stands over the entrance to the Mercerie on the northern side of St. Mark's Square. Detailed surveys and mapping of both building materials (mainly stones) and deterioration patterns were carried out, the latter following the glossary of weathering forms, coupled with an easy-to-use scale of evaluation of their intensity. The data output consists of several monothematic maps which can be handled separately, each one focusing on precise lithological or specific deterioration aspects. This study also proposes a simple approach to summarizing the total state of deterioration of the building in the form of a Total Deterioration Rank (TDR) and its representation. The stones used in the facade are regional (Ammonitico Rosso and Scaglia Rossa) and extra-regional limestones (Istrian Stone), as well as Mediterranean white and coloured marbles and stones already used in antiquity (i.e., Fior di Pesco or marmor chalcidicum, lapis porphyrites, a volcanic rock from the Egyptian Eastern Desert, Proconnesian marble from the Island of Marmara, Pavonazzetto toscano and white Carrara marble from the Italian Apuan Alps). The most frequent forms of deterioration detected are black crusts, patinas, discoloration and patterns linked to erosion processes. The interrelation of different mappings led to a number of useful considerations concerning differences in the effectiveness of maintenance procedures between public and private management of the monument
SUS-BAR: a database of pig proteins with statistically validated structural and functional annotation
Given the relevance of the pig proteome in different studies, including human complex maladies, a statistical validation of the annotation is required for a better understanding of the role of specific genes and proteins in the complex networks underlying biological processes in the animal. Presently, approximately 80% of the pig proteome is still poorly annotated, and the existence of protein sequences is routinely inferred automatically by sequence alignment towards preexisting sequences. In this article, we introduce SUS-BAR, a database that derives information mainly from UniProt Knowledgebase and that includes 26 206 pig protein sequences. In SUS-BAR, 16 675 of the pig protein sequences are endowed with statistically validated functional and structural annotation. Our statistical validation is determined by adopting a cluster-centric annotation procedure that allows transfer of different types of annotation, including structure and function. Each sequence in the database can be associated with a set of statistically validated Gene Ontologies (GOs) of the three main sub-ontologies (Molecular Function, Biological Process and Cellular Component), with Pfam functional domains, and when possible, with a cluster Hidden Markov Model that allows modelling the 3D structure of the protein. A database search allows some statistics demonstrating the enrichment in both GO and Pfam annotations of the pig proteins as compared with UniProt Knowledgebase annotation. Searching in SUS-BAR allows retrieval of the pig protein annotation for further analysis. The search is also possible on the basis of specific GO terms and this allows retrieval of all the pig sequences participating into a given biological process, after annotation with our system. Alternatively, the search is possible on the basis of structural information, allowing retrieval of all the pig sequences with the same structural characteristics
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Children Develop a Veil of Fairness
Previous research suggests that children develop an increasing concern with fairness over the course of development. Research with adults suggests that the concern with fairness has at least two distinct components: a desire to be fair but also a desire to signal to others that they are fair. We explore whether children’s developing concern with behaving fairly towards others may in part reflect a developing concern with appearing fair to others. In Experiments 1-2, most 6- to 8-year-old children behaved fairly towards others when an experimenter was aware of their choices; fewer children opted to behave fairly, however, when they could be unfair to others yet appear fair to the experimenter. In Experiment 3, we explored the development of this concern with appearing fair by using a wider age range (6- to 11-year-olds) and a different method. In this experiment, children chose how to assign a good or bad prize to themselves and another participant by either unilaterally deciding who would get each prize or by using a fair procedure – flipping a coin in private. Older children were much more likely to flip the coin than younger children, yet were just as likely as younger children to assign themselves the good prize by reporting winning the coin flip more than chance would dictate. Overall, the results of these experiments suggest that as children grow older they become increasingly concerned with appearing fair to others, which may explain some of their increased tendency to behave fairly
Children develop a veil of fairness.
Previous research suggests that children develop an increasing concern with fairness over the course of development. Research with adults suggests that the concern with fairness has at least 2 distinct components: a desire to be fair and a desire to signal to others that they are fair. We explore whether children's developing concern with behaving fairly toward others may in part reflect a developing concern with appearing fair to others. In Experiments 1 and 2, most 6- to 8-year-old children behaved fairly toward others when an experimenter was aware of their choices; fewer children opted to behave fairly, however, when they could be unfair to others yet appear fair to the experimenter. In Experiment 3, we explored the development of this concern with appearing fair by using a wider age range (6- to 11-year-olds) and a different method. In this experiment, children chose how to assign a good or bad prize to themselves and another participant by either unilaterally deciding who would get each prize or using a fair procedure-flipping a coin in private. Older children were much more likely to flip the coin than younger children, yet were just as likely as younger children to assign themselves the good prize by reporting winning the coin flip more than chance would dictate. Overall, the results of these experiments suggest that as children grow older they become increasingly concerned with appearing fair to others, which may explain some of their increased tendency to behave fairly.© 2013 American Psychological Association
Electromagnetic filaments and edge modifications induced by electrode biasing in the RFX-mod tokamak
BAR-PLUS: the Bologna Annotation Resource Plus for functional and structural annotation of protein sequences
We introduce BAR-PLUS (BAR+), a web server for functional and structural annotation of protein sequences. BAR+ is based on a large-scale genome cross comparison and a non-hierarchical clustering procedure characterized by a metric that ensures a reliable transfer of features within clusters. In this version, the method takes advantage of a large-scale pairwise sequence comparison of 13 495 736 protein chains also including 988 complete proteomes. Available sequence annotation is derived from UniProtKB, GO, Pfam and PDB. When PDB templates are present within a cluster (with or without their SCOP classification), profile Hidden Markov Models (HMMs) are computed on the basis of sequence to structure alignment and are cluster-associated (Cluster-HMM). Therefrom, a library of 10 858 HMMs is made available for aligning even distantly related sequences for structural modelling. The server also provides pairwise query sequence–structural target alignments computed from the correspondent Cluster-HMM. BAR+ in its present version allows three main categories of annotation: PDB [with or without SCOP (*)] and GO and/or Pfam; PDB (*) without GO and/or Pfam; GO and/or Pfam without PDB (*) and no annotation. Each category can further comprise clusters where GO and Pfam functional annotations are or are not statistically significant. BAR+ is available at http://bar.biocomp.unibo.it/bar2.0
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