275 research outputs found

    The Cost of Social Agents

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    In this paper we follow the BOID (Belief, Obligation, Intention, Desire) architecture to describe agents and agent types in Defeasible Logic. We argue that the introduction of obligations can provide a new reading of the concepts of intention and intentionality. Then we examine the notion of social agent (i.e., an agent where obligations prevail over intentions) and discuss some computational and philosophical issues related to it. We show that the notion of social agent either requires more complex computations or has some philosophical drawbacks

    Solunto archaeological park in Sicily: life under mosaic tesserae

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    Biodeterioration is a complex process induced by the growing and metabolic activity of a wide range of macro and microorganisms, becoming a revelling problem also for the mosaic tesserae of “Casa di Leda” in the Greco - Roman site of Solunto in Sicily. In this case-study, a thick biofilm inducing a deep alteration of mortar and consequently the mosaic tesserae detachment has been highlighted during the restoration plan. The biofilm microbial consortium has been investigated by an integrate approach based on Microscopy analysis (O.M., C.L.S.M.), in vitro culture (Nutrien and Saboraud media) and molecular biology investigation (DNA target sequence amplification, sequencing, sequence analysis). A microbial diversity has been revealed belonging to bacteria (Bacillus) and fungi (Alternaria, Aspergillus), besides cyanobacteria (Chroococcus) and green algae (Chlorella). In order to control the biofilm colonization two essential oils (EO), Thymus vulgaris and Origanum vulgare, have been utilized and their antimicrobial activity, preliminarily in vitro (agar disc diffusion methods) and after ex situ and in situ evaluated. This experimentation is aimed at identifying and implementing green biocides for the control of microbial colonization, a promising technology with a reduced impact on human health and environment, able to replace traditional biocide action

    Cervico-mediastinal schwannoma of the vagus nerve: resection with intraoperative nerve monitoring.

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    Schwannomas are usually benign, single, encapsulated, slow-growing tumours originating from cranial or spinal nerve sheaths. The vagus nerve involvement at the mediastinal inlet is very uncommon. For anatomical reasons, the resection of cervical and mediastinal schwannoma of the vagus nerve has a high risk of vocal fold paralysis. We describe the case of a 67-year-old female with a cervico-mediastinal schwannoma of the vagus nerve that we removed using the intraoperative neuromonitoring technique. The patient presented with mild hoarseness and complained of discomfort behind the jugular notch. Neck and chest computerized tomography described a 35 9 30 mm solid lesion behind the left clavi-sternal junction; preoperative fine needle aspiration cytology revealed schwannoma. Resection of the mass was performed with a cervical approach and the vagus nerve tumour was completely removed under continuous neuromonitoring (NIM-3 System), preserving the vagus and the recurrent laryngeal nerve function. Pathology on the resected mass documented A-type schwannoma with \u2018\u2018ancient schwannoma\u2019\u2019 areas. The intraoperative neurostimulation and neuromonitoring approach for the resection of vagus schwannoma are recommended because it may reduce the risk of injury to the vagus and to the recurrent laryngeal nerve

    Prevalence of heavy smokers in the year 2000 in the province of Varese, Italy.

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    ABSTRACT: Prevalence of heavy smokers in the year 2000 in the Province of Varese, Italy. A. Imperatori, N. Rotolo, V. Conti, D. Di Natale, V. Tropeano, W. Mantovani. Background. Knowing the prevalence of heavy smokers (HS) by gender and age is a pre-requisite for bringing into effect public health measures against smoking-related diseases. Smoking prevalence data is available for the Italian Regions, however it is generally unknown for the Italian Provinces. Methods. In the year 2000 a survey of smoking prevalence was conducted by 47 general practitioners (GPs), by personal interview, in a large sample of the Varese Province population 45-74 years of age (28,034 subjects; 13,528 men, 14,506 women). Each surveyed subject was categorised either as ever HS (current/former smoker of at least 10 pack-years) or as non HS. The information on smoking habit collected by the GPs was anonymously pooled for analysis. Prevalence figures of smoking were tabulated by gender and by 5-year age-strata. Results. In the population 45-74 years of age the percentage of ever HS overall was 22.3% (34.4% of men; 11.0% of women). The prevalence of ever HS in both sexes combined progressively decreased with advancing age, from 23.6% (45-49 year stratum) to 19.5% (70-74 year stratum). Current HS were 24.5% of men and 9.5% of women. Conclusions. The year 2000 survey on smoking habit, showing 22.3% prevalence of ever HS in age range 45-74 years, is the first conducted in the Varese Province using a large population sample. The data on heavy cigarette smoking presented in this paper, stratified by gender and age, may be used to monitor changes in the smoking habit and in the incidence of smoking-related illnesses at the provincial level

    First measurements of the Fe oxidation state of spinel inclusions inolivine single crystals from Vulture (Italy) with the in situ synchrotronmicro-Mossbauer technique

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    The redox state of the Earth's upper mantle (i.e., oxygen fugacity, f(O2)) is a key variable that influences numerous processes occurring at depth like the mobility of volatile species, partial melting, and metasomatism. It is linked to the oxidation state of peridotite rocks, which is normally determined through the available oxythermobarometers after measuring the chemical composition of equilibrated rock-forming minerals and the Fe3+ in redox-sensitive minerals like spinel or garnet. To date, accurate measurements of Fe3+ / Sigma Fe in peridotites have been limited to those peridotites (e.g., harzburgites and lherzolites) for which an oxythermobarometer exists and where spinel (or garnet) crystals can be easily separated and measured by conventional Fe-57 Mossbauer spectroscopy. Wehrlitic rocks have been generally formed by the interaction of a lherzolite with carbonatitic melts and, therefore, have recorded the passage of (metasomatic) fluids at mantle conditions. However, no oxythermobarometer exists to determine their equilibrium f(O2).The aim of this study was to retrieve the f(O2) of the mantle beneath Mt. Vulture volcano (Italy) through the study of a wehrlitic lapillus emitted during the last eruption (similar to 140 kyr ago) that contain olivines with multiple tiny spinel inclusions with sizes < 40 mu m. To our knowledge, the Fe oxidation state of these inclusions has been never determined with the Mossbauer technique due to their small sizes.Here, we present measurements of the Fe3+ / Sigma Fe using in situ synchrotron Mossbauer spectroscopy coupled with chemical and spectroscopic analysis of both host olivine and spinel inclusions.The results show Fe3+ / Sigma Fe ratios of 0.03-0.05 for olivine and 0.40-0.45 for the included spinels, the latter of which appear higher than those reported in literature for mantle spinel harzburgites and lherzolites. Given the evidence of the mantle origin of the trapped spinels, we propose that the high f(O2) (between 0.81 and 1.00 log above the fayalite-magnetite-quartz buffer; FMQ) likely results from the interaction between the pristine spinel lherzolite and a CO2-rich metasomatic agent prior to the spinel entrapment in olivines at mantle depths

    First measurements of the Fe oxidation state of spinel inclusions in olivine single crystals from Vulture (Italy) with the in situ synchrotron micro-Mössbauer technique

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    The redox state of the Earth's upper mantle (i.e., oxygen fugacity, fO2) is a key variable that influences numerous processes occurring at depth like the mobility of volatile species, partial melting, and metasomatism. It is linked to the oxidation state of peridotite rocks, which is normally determined through the available oxythermobarometers after measuring the chemical composition of equilibrated rock-forming minerals and the Fe3+ in redox-sensitive minerals like spinel or garnet. To date, accurate measurements of Fe3+ / ∑Fe in peridotites have been limited to those peridotites (e.g., harzburgites and lherzolites) for which an oxythermobarometer exists and where spinel (or garnet) crystals can be easily separated and measured by conventional 57Fe Mössbauer spectroscopy. Wehrlitic rocks have been generally formed by the interaction of a lherzolite with carbonatitic melts and, therefore, have recorded the passage of (metasomatic) fluids at mantle conditions. However, no oxythermobarometer exists to determine their equilibrium fO2. The aim of this study was to retrieve the fO2 of the mantle beneath Mt. Vulture volcano (Italy) through the study of a wehrlitic lapillus emitted during the last eruption (∌ 140 kyr ago) that contain olivines with multiple tiny spinel inclusions with sizes &lt; 40 ”m. To our knowledge, the Fe oxidation state of these inclusions has been never determined with the Mössbauer technique due to their small sizes. Here, we present measurements of the Fe3+ / ∑Fe using in situ synchrotron Mössbauer spectroscopy coupled with chemical and spectroscopic analysis of both host olivine and spinel inclusions. The results show Fe3+ / ∑Fe ratios of 0.03–0.05 for olivine and 0.40–0.45 for the included spinels, the latter of which appear higher than those reported in literature for mantle spinel harzburgites and lherzolites. Given the evidence of the mantle origin of the trapped spinels, we propose that the high fO2 (between 0.81 and 1.00 log above the fayalite–magnetite–quartz buffer; FMQ) likely results from the interaction between the pristine spinel lherzolite and a CO2-rich metasomatic agent prior to the spinel entrapment in olivines at mantle depths.</p

    A two-component mantle source feeding Mt. Etna magmatism; insights from the geochemistry of primitive magmas.

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    The major elements, trace elements and Sr and Nd isotopes of selected Etnean primitive rocks (b15 ky BP) were studied in order to characterize their mantle source. The noble-gas geochemistry of fluid inclusions in minerals fromthe same lavaswas also investigated. Themajor element compositions ofwhole rocks and minerals showed that these products are among the most primitive atMt. Etna, comprising 6.3–17.5 wt.% MgO. The variable LREE (Light Rare Earth Elements) enrichment relative to MORB (Mid-Ocean Ridge Basalt) (Lan/Ybn = 11–26), togetherwith the patterns of certain trace-element ratios (i.e., Ce/Yb versus Zr/Nb and Th/Y versus La/Yb), can be attributed to varying degrees of melting of a common mantle source. Numerical simulations performed with the MELTS program allowed the melting percentages associated with each product to be estimated. This led us to recalculate the hypothetical parental trace-element content of the Etneanmantle source, whichwas common to all of the investigated rocks. The characteristics of the Sr, Nd and He isotopes confirmed the primitive nature of the rocks,with themost-depleted and primitive lava being that ofMt. Spagnolo (SPA; 143Nd/144Nd = 0.512908 87Sr/ 86Sr = 0.703317–0.703325 and 3He/4He = 7.6 Ra), and highlighted the similarity of the mantle sources feeding the volcanic activity of Mt. Etna and the Hyblean Plateau (a region to the south of Mt. Etna and characterized by oldermagmatismthan Mt. Etna). The coupling of noble gases and trace elements suggests an origin for the investigated Etnean lavas from melting of a Hyblean-like mantle, consisting of a two-component source where a peridotitic matrix is veined by 10% pyroxenite. A variable degree of mantle contamination by crustal-like fluids, probably related to subduction, is proposed to explain the higher Sr-isotope and lowerNd-isotope values in some rocks (143Nd/144Nd up to 0.512865 and 87Sr/86Sr up to 0.703707). This process probably occurred in the source prior tomagma generation, refertilizing some portions of themantle. Accordingly, the estimated degree of melting responsible for each magma appears to be related to its 87Sr/86Sr enrichment. In contrast, the decoupling between 3He/4He and 87Sr/86Sr ratios requires the occurrence in the crustal reservoirs of further processes capable of shifting the He isotope ratio towards slightly more radiogenic values, such as magma aging or a contribution of shallow fluid. Therefore, different residence times in the Etnean reservoir and/or various rates of magma ascent could be key parameters for preserving the original He isotope marker of the Etnean mantle source. © 2013 Published by Elsevier

    Self-selection effects in smokers attending lung cancer screening: a 9.5-year population-based cohort study in Varese, Italy.

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    BACKGROUND:: We hypothesize that mortality risk profile of participants and nonparticipants in nonrandomized lung cancer (LC) screening of smokers may be different. METHODS:: In 1997, a population-based cohort of 5815 smokers of Varese Province was invited to nonrandomized LC screening by annual chest x-ray examination for 4 years. LC risk factors and screening participation rate were recorded. Except for screening, the whole cohort received usual care. After 9.5-year observation, we compared mortality of participants versus nonparticipants by assessing age-standardized all-cause mortality rate ratio (MRR) and disease group-specific MRR with 95% confidence intervals (95% CI). RESULTS:: Self-selected screening participants were 21% of cohort. Participants were younger (p < 0.001), were more frequently current smokers (p = 0.019), had more pack-years of smoking (p < 0.0001), and had higher rate of LC family history (p < 0.0001) and of occupational LC risk (p < 0.0001) relative to nonparticipants. In logistic regression analysis familial LC, occupational risk and pack-years smoked were significant predictors of participation in screening and of developing LC. Participants displayed a healthy effect, as shown by all-cause MRR = 0.67 (95% CI, 0.53-0.84), all cancers except LC MRR = 0.61 (95% CI, 0.41-0.91), cardiovascular diseases MRR = 0.38 (95% CI, 0.22-0.63), and noncancer disease other than cardiovascular or respiratory MRR = 0.57 (95% CI, 0.34-0.92). The LC mortality (MRR = 1.40; 95% CI, 1.03-1.91) was higher in participants relative to nonparticipants (p = 0.031). CONCLUSION:: The selection effect in LC screening participants was dual: healthy effect and higher LC mortality. In assessing the overall effectiveness of LC screening on a population level, a higher LC mortality risk in participants should be considered

    Prognostic role of aldosterone in patients with acute coronary syndrome: short and medium term follow-up.

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    AIMS: Different studies have shown a correlation between aldosterone, atherosclerosis and ischemia in the past decade. Evidence exists for the relationship between high levels of aldosterone and augmented risk of cardiovascular diseases, such as hypertension, cardiac failure, coronary artery disease and stroke. The objective of this study was to determine the prognostic role of aldosterone in patients with myocardial infarction. METHODS:The study population included 96 consecutive patients admitted to our department for ST-elevated and non-ST-elevated myocardial infarction from June 2009 to March 2012. Plasma aldosterone levels were measured at admission to hospital in all patients. A 2-year prospective follow-up was performed, and fatal events and non-fatal events, such as reinfarction, congestive heart failure and arrhythmias, were recorded. RESULTS:Aldosterone levels at admission were associated with incidence of congestive heart failure (P\u200a=\u200a0.02), ventricular arrhythmias (P\u200a=\u200a0.01) and all complications (P\u200a=\u200a0.003) after 1-month follow-up. Moreover, high aldosterone levels gave important information in the medium term (24\u200a\ub1\u200a6 months). Specifically, aldosterone was a predictive variable of reinfarction (P\u200a<\u200a0.0001), congestive heart failure (P\u200a<\u200a0.0001) and adverse events (P\u200a=\u200a0.0002). The logistic regression analysis confirmed these results and showed that aldosterone may be predictive of adverse events at medium-term follow-up (odds ratio 1.1, 95% confidence interval 1.03-1.15, P\u200a=\u200a0.02). CONCLUSION:These data show a strong and significant correlation between plasma aldosterone levels at admission for myocardial infarction and fatal and nonfatal adverse events. Aldosterone appears to be a main marker of adverse clinical outcome, in accordance with the literature. These data suggest the need to identify whether antialdosteronic drug treatment, applied acutely in patients with aldosterone elevation, can influence favorably the prognosis of patients with myocardial infarction
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