58 research outputs found

    Hierarchical Time-Varying Estimation of Asset Pricing Models

    Get PDF
    This paper presents a new hierarchical methodology for estimating multi factor dynamic asset pricing models. The approach is loosely based on the sequential Fama–MacBeth approach and developed in a kernel regression framework. However, the methodology uses a very flexible bandwidth selection method which is able to emphasize recent data and information to derive the most appropriate estimates of risk premia and factor loadings at each point in time. The choice of bandwidths and weighting schemes are achieved by a cross-validation procedure; this leads to consistent estimators of the risk premia and factor loadings. Additionally, an out-of-sample forecasting exercise indicates that the hierarchical method leads to a statistically significant improvement in forecast loss function measures, independently of the type of factor considered

    Planning and optimisation of the stratospheric gondola project: search for a standard

    Get PDF

    Application Of Safety And Security Principles To Flood Event Management In Highly Populated Urban Areas

    Get PDF
    This paper refers to non-structural actions which are to be carried out on the Arno river basin (Italy). In particular the town of Florence is considered where 56 catastrophic flood events have been recorded in the last 1000 years, the latter in 1966 with damages estimated at 10,000 billion euros. A huge system of structural works is presently being carried out planned to the 200-year return period event in the next ten years. To manage the present and future residual risk, specific safety plans have been provided at the scale of single buildings in order to give residents an effective instrument to prevent and protect them from the major flooding risk. This paper illustrates how safety and security principles can be applied to the management of a flood event at the scale of several thousands of square kilometres. A specific Security Plan and, if needed, a Recovery Plan is linked to each building which is potentially subject to flooding. Based on analytical hazard assessment and mapping, techniques to improve or increase the safety-level as well as appropriated information are described. These local scale plans are interfaced with civil protection and disaster management plans at the regional scale by suitable procedures. Keywords: risk assessment, flood event, security plan, recovery plan, signs, procedures, building. 1 Introduction A study for a plan in order to provide the residents of the area of the Arno River basin (and in future perspective all the residents) with one useful instrument t

    Stepping through versatile attitude control system design for stratospheric platforms

    Get PDF

    13q Deletion Syndrome Involving RB1: Characterization of a New Minimal Critical Region for Psychomotor Delay.

    Get PDF
    Retinoblastoma (RB) is an ocular tumor of the pediatric age caused by biallelic inactivation of the RB1 gene (13q14). About 10% of cases are due to gross-sized molecular deletions. The deletions can involve the surrounding genes delineating a contiguous gene syndrome characterized by RB, developmental anomalies, and peculiar facial dysmorphisms. Overlapping deletions previously found by traditional and/or molecular cytogenetic analysis allowed to define some critical regions for intellectual disability (ID) and multiple congenital anomalies, with key candidate genes. In the present study, using array-CGH, we characterized seven new patients with interstitial 13q deletion involving RB1. Among these cases, three patients with medium or large 13q deletions did not present psychomotor delay. This allowed defining a minimal critical region for ID that excludes the previously suggested candidate genes (HTR2A, NUFIP1, PCDH8, and PCDH17). The region contains 36 genes including NBEA, which emerged as the candidate gene associated with developmental delay. In addition, MAB21L1, DCLK1, EXOSC8, and SPART haploinsufficiency might contribute to the observed impaired neurodevelopmental phenotype. In conclusion, this study adds important novelties to the 13q deletion syndrome, although further studies are needed to better characterize the contribution of different genes and to understand how the haploinsufficiency of this region can determine ID. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

    Strategies for preventing group B streptococcal infections in newborns: A nation-wide survey of Italian policies

    Get PDF

    Ancoraggio lastre in vetro

    No full text
    Domanda di Brevetto FI2005A000066 depositata il 11.4.2005 alla Camera di Commercio di Firenze, primo assegnatario Università degli Studi di Firenze, acquistato da Logli Massimo srl

    A randomized controlled study comparing harmonic versus electrosurgery in laparoscopic myomectomy.

    Get PDF
    Abstract OBJECTIVE: To compare the effectiveness and safety of harmonic scalpel versus electrosurgery to reduce blood loss during laparoscopic myomectomy. DESIGN: Prospective randomized controlled study. SETTING: Tertiary referral centers for gynecological care. PATIENT(S): One hundred sixty consecutive premenopausal women with symptomatic uterine leiomyomata who were assigned to one of the two treatment groups (a total of 80 patients in each group): treatment with electrosurgery devices with a vasoconstrictive solution (50 mL of saline solution and 0.5 mL of epinephrine [1/2 vial of 1 mg/mL]; group A) or harmonic scalpel (group B). INTERVENTION(S): Laparoscopic myomectomy. MAIN OUTCOMES MEASURE(S): The global operative time, the time spent for myoma enucleation and for suturing uterine wall defects, and intraoperative blood loss as well as the surgical difficulty degree and postoperative pain at 24 and 48 hours after the laparoscopic procedure. RESULT(S): No relevant intra- or postoperative complications were observed in either group. The degree of pain 24 hours after surgery was significantly lower in patients in whom the harmonic scalpel was used. The degree of surgical difficulty did not differ between groups, but the global operative time was significantly shorter in the harmonic scalpel group. CONCLUSION(S): The use of the harmonic scalpel for laparoscopic myomectomy is associated with low total operative time, low intraoperative blood loss, and low postoperative pain, with no increase in surgical difficulty
    • …
    corecore