29 research outputs found

    Asset prices and portfolio choice with learning from experience

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    We study asset prices and portfolio choice with overlapping generations, where the young disregard history to learn from own experience. Disregarding history implies less precise estimates of output growth, which in equilibrium leads the young to increase their investment in risky assets after positive returns, that is, they act as trend chasers. In equilibrium, the risk premium decreases after a positive shock and, therefore, trend chasing young agents lose wealth relative to old agents who behave as contrarians. Consistent with findings from survey data, the average belief about the risk premium in the economy relates negatively to future excess returns and is smoother than the true risk premium

    Improvement of adiponectin in relation to physical performance and body composition in young obese males subjected to twenty-four weeks of training programs

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    Obesity and related metabolic diseases represent a worldwide health problem. The main factor predisposing to obesity is an unhealthy lifestyle including the lack of physical activity. A pivotal role in the etio-pathogenesis of obesity is carried out by adipose tissue, an endocrine organ secreting several adipokines involved in numerous metabolic and inflammatory processes. Among these, of particular importance is adiponectin, an adipokine involved in the regulation of insulin sensibility and in anti-inflammatory processes. The aim of the study was to determine the effects of 24 weeks of two different training programs polarized (POL) and threshold training (THR) on body composition, physical capacities and adiponectin expression. Thirteen male obese subjects (BMI: 32.0 ± 3.0 kg m-2) followed 24 weeks of two different training programs, POL and THR, consisting of walking or running (or a combination of the two methods) in their normal living conditions. Before (T0) and after the end of the program (T1), the assessment of body composition was assessed by bioelectrical impedance and the concentration of salivary and serum adiponectin was analyzed by enzyme-linked immunosorbent assay and western blotting. Although the results obtained did not show significant differences between the two training programs, body mass and body mass index decreased by a mean of −4.46 ± 2.90 kg and 1.43 ± 0.92 kg m−2 (P < 0.05). Fat mass decreased by −4.47 ± 2.78 kg (P < 0.05). Vâ€ČO2max increased by a mean of 0.20 ± 0.26 L min−1 (P < 0.05) Also, we observed an increase in saliva and in serum of adiponectin concentrations at T1 compared to T0 by 4.72 ± 3.52 ÎŒg mL−1 and 5.22 ± 4.74 ng mL−1 (P < 0.05) respectively. Finally, we found significant correlations between Δ serum adiponectin and Δ Hip (R = −0.686, P = 0.001) and between Δ salivary adiponectin and ΔWaist (R = −0.678, P = 0.011). Our results suggest that a 24 weeks training program, independently from intensity and volume, induces an amelioration of body composition and fitness performance. These improvements are associated with an increase in total and HMW adiponectin expression in both saliva and in serum

    The challenge of studying perovskite solar cells stability with machine learning

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    Perovskite solar cells are the most dynamic emerging photovoltaic technology and attracts the attention of thousands of researchers worldwide. Recently, many of them are targeting device stability issues the key challenge for this technology which has resulted in the accumulation of a significant amount of data. The best example is the Perovskite Database Project, which also includes stability related metrics. From this database, we use data on 1,800 perovskite solar cells where device stability is reported and use Random Forest to identify and study the most important factors for cell stability. By applying the concept of learning curves, we find that the potential for improving the models performance by adding more data of the same quality is limited. However, a significant improvement can be made by increasing data quality by reporting more complete information on the performed experiments. Furthermore, we study an in house database with data on more than 1,000 solar cells, where the entire aging curve for each cell is available as opposed to stability metrics based on a single number. We show that the interpretation of aging experiments can strongly depend on the chosen stability metric, unnaturally favoring some cells over others. Therefore, choosing universal stability metrics is a critical question for future databases targeting this promising technolog

    The T.O.S.C.A. Project: Research, Education and Care

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    Despite recent and exponential improvements in diagnostic- therapeutic pathways, an existing “GAP” has been revealed between the “real world care” and the “optimal care” of patients with chronic heart failure (CHF). We present the T.O.S.CA. Project (Trattamento Ormonale dello Scompenso CArdiaco), an Italian multicenter initiative involving different health care professionals and services aiming to explore the CHF “metabolic pathophysiological model” and to improve the quality of care of HF patients through research and continuing medical education

    Uniting statistical and individual-based approaches for animal movement modelling

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    <div><p>The dynamic nature of their internal states and the environment directly shape animals' spatial behaviours and give rise to emergent properties at broader scales in natural systems. However, integrating these dynamic features into habitat selection studies remains challenging, due to practically impossible field work to access internal states and the inability of current statistical models to produce dynamic outputs. To address these issues, we developed a robust method, which combines statistical and individual-based modelling. Using a statistical technique for forward modelling of the IBM has the advantage of being faster for parameterization than a pure inverse modelling technique and allows for robust selection of parameters. Using GPS locations from caribou monitored in Québec, caribou movements were modelled based on generative mechanisms accounting for dynamic variables at a low level of emergence. These variables were accessed by replicating real individuals' movements in parallel sub-models, and movement parameters were then empirically parameterized using Step Selection Functions. The final IBM model was validated using both k-fold cross-validation and emergent patterns validation and was tested for two different scenarios, with varying hardwood encroachment. Our results highlighted a functional response in habitat selection, which suggests that our method was able to capture the complexity of the natural system, and adequately provided projections on future possible states of the system in response to different management plans. This is especially relevant for testing the long-term impact of scenarios corresponding to environmental configurations that have yet to be observed in real systems.</p></div

    Red Sea palaeoclimate: stable isotope and element-ratio analysis of marine mollusc shells

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    The southern Red Sea coast is the location of more than 4,200 archaeological shell midden sites. These shell middens preserve archaeological and climatic archives of unprecedented resolution and scale. By using shells from these contexts, it is possible to link past environmental information with episodes of human occupation and resource processing. This chapter summarises current knowledge about the marine gastropod Conomurex fasciatus (Born 1778) and discusses its use in environmental and climatic reconstruction using stable isotope and elemental ratio analysis. It offers a review of the most recent studies of shell midden sites on the Farasan Islands, their regional importance during the mid-Holocene, theories about seasonal use of the coastal landscape, and preliminary results from new methods to acquire large climatic datasets from C. fasciatus shells

    Distribution of bog and heath in a Newfoundland blanket bog complex: topographic limits on the hydrological processes governing blanket bog development

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    This research quantified the role of topography and hydrological processes within and, hence, the development of, blanket bogs. Topographic characteristics were derived from digital elevation models (DEMs) developed for the surface and underlying substrate at three blanket bog sites on the southeastern lobe of the Avalon Peninsula, Newfoundland. A multinomial logit (MNL) model of the probability of bog occurrence was constructed in terms of relevant topographic characteristics. The resulting model was then used to investigate the probabilistic boundary conditions of bog occurrence within the landscape. Under average curvatures for the sites studied, substrate slopes up to 0.065 favoured blanket bog development. However, steeper slopes could, theoretically, be occupied by blanked bog where water is concentrated by convergent curvatures or large contributing areas. Near community boundaries, bog and heath communities both occupied similar topographic conditions. Since these boundary locations are capable of supporting the hydrological conditions necessary for bog development, the heath is likely to be encroached upon by bog

    designing [in] greenfield WORKSHOP_LABORATORIO DI PROGETTAZIONE INTENSIVA INTENSIVE DESIGN WORKSHOP The case study of an area in northern Napoli

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    designing [in] greenfield a cura di Marino Borrelli e Agrippino Graniero WORKSHOP_LABORATORIO DI PROGETTAZIONE INTENSIVA INTENSIVE DESIGN WORKSHOP INTENSIVE DESIGN WORKSHOP I lavori presentati sono il risultato del secondo Workshop/Laboratorio di progettazione intensiva “designing [in] greenfield” svolto nel Dipartimento di Architettura e Disegno Industriale della Seconda Università degli Studi di Napoli nel corso di Laurea in Architettura a ciclo unico. The presented works are the result of the second intensive design Workshop "designing [in] greenfield" carried out in the Dipartimento di Architettura e Disegno Industriale of Seconda Università degli Studi di Napoli in the Degree course in Architettura. La diffusione dei risultati della sperimentazione progettuale nell’ambito dell’attività didattica e della ricerca progettuale e la sua divulgazione gratuita in ambiti scientifici ed accademici garantita da un marchio libero come AOS sembra allo stato un meccanismo vincente, così come dimostra l’alto numero di download delle pubblicazioni prodotte e dell’ibook del primo Workshop della facoltà di Architettura della seconda Università di Napoli e la buona qualità del lavoro di questo secondo anch’esso prodotto nel formato ibook della apple, dotato di un comitato scientifico internazionale e distribuito gratuitamente in italiano e in inglese in 51 paesi.The presented works are the result of the second intensive design Workshop "designing [in] greenfield" carried out in the Dipartimento di Architettura e Disegno Industriale of Seconda Università degli Studi di Napoli in the Degree course in Architettura

    Distribution of bog and heath in a Newfoundland blanket bog complex: topographic limits on the hydrological processes governing blanket bog development

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    International audienceThis research quantified the role of topography and hydrological processes within and, hence, the development of, blanket bogs. Topographic characteristics were derived from digital elevation models (DEMs) developed for the surface and underlying substrate at three blanket bog sites on the southeastern lobe of the Avalon Peninsula, Newfoundland. A multinomial logit (MNL) model of the probability of bog occurrence was constructed in terms of relevant topographic characteristics. The resulting model was then used to investigate the probabilistic boundary conditions of bog occurrence within the landscape. Under average curvatures for the sites studied, substrate slopes up to 0.065 favoured blanket bog development. However, steeper slopes could, theoretically, be occupied by blanked bog where water is concentrated by convergent curvatures or large contributing areas. Near community boundaries, bog and heath communities both occupied similar topographic conditions. Since these boundary locations are capable of supporting the hydrological conditions necessary for bog development, the heath is likely to be encroached upon by bog
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