74 research outputs found
Overconfidence and market efficiency with heterogeneous agents
We study financial markets in which both rational and overconfident agents coexist and make endogenous information acquisition decisions. We demonstrate the following irrelevance result: when a positive fraction of rational agents (endogeneously) decides to become informed in equilibrium, prices are set as if all investors were rational, and as a consequence the overconfidence bias does not aect informational efficiency, price volatility, rational traders’ expected profits or their welfare. Intuitively, as overconfidence goes up, so does price infornativeness, which makes rational agents cut their information acquisition activities, effectively undoing the standard effect of more aggressive trading by the overconfident.Partially revealing equilibria, overconfidence, rational expectations, information
Overconfidence and Market Efficiency with Heterogeneous Agents
We study financial markets in which both rational and overconfident agents coexist and make endogenous information acquisition decisions. We demonstrate the following irrele- vance result: when a positive fraction of rational agents (endogenously) decides to become informed in equilibrium, prices are set as if all investors were rational, and as a conse- quence the overconfidence bias does not affect informational efficiency, price volatility, ra- tional traders expected profits or their welfare. Intuitively, as overconfidence goes up, so does price informativeness, which makes rational agents cut their information acquisition activities, effectively undoing the standard effect of more aggressive trading by the overcon- fident. The main intuition of the paper, if not the irrelevance result, is shown to be robust to different model specifications.partially revealing equilibria, overconfidence, rational expectations, information acquisition, price informativeness.
A multicenter study on reliability and validity of a new triage system: the Triage Emergency Method version 2
In Italy there are many triage guidelines and methods based on consensus. But, to our knowledge, there are few data on the reliability and predictive validity of triage systems adopted by Italian emergency departments. The Triage Emergency Method version 2 (TEM v2) is a new four-level in-hospital triage system. This paper presentes a before-and-after observational study performed using triage scenarios from June 2008 to September 2009 in 6 Italian emergency departments. Twelve nurses who received a 5-h training on TEM and a panel of experts on TEM assigned priority code to 66 scenarios. To test the inter-rater reliability among participants and the panel of experts (before and after the course), we used the weighted K statistic. We assessed the validity of TEM by calculating sensitivity, specificity and accuracy for predicting the reference standard's triage score. The TEM v2 showed good and very-good agreement among all 6 groups of nurses with a K range=0.61-1. Also, sensitivity, specificity and accuracy of nurses' triage rating for predicting the reference standard's triage code was good (accuracy range=78-90%). In this multicenter study, TEM v2 has a good inter-rater reliability for rating triage acuity among all groups of participating nurses, with a K value similar to the reference standard reliability (K=0.75). Thus, the Triage Emergency Method version 2 seems to be valid and accurate in predicting a reference standard rating
Analysis of drug utilization and health care resource consumption in patients with psoriasis and psoriatic arthritis before and after treatment with biological therapies
To describe the therapeutic pathways of patients with psoriasis (PSO) and psoriatic arthritis (PsA) before and after treatment with biological therapies in a real-world setting and to determine the relative consumption of health care resources
Simulation Study of Multi-wire front Contact Grids for Silicon Solar Cells
Abstract Multi-wire (MW) front-contact schemes represent a promising alternative to standard H-pattern structure with ribbon busbar (BB) in silicon solar cells. In the case of MW schemes, busbar are replaced by copper wires. MW have been demonstrated to enhance the photo-generation with respect to a standard H-pattern structure with ribbon busbar when solar cells are encapsulated and assembled in modules. However, the influence of the geometrical and optical properties of the encapsulation layers as well as of wires on the optical effective shading is not exhaustively treated by the literature. In this work, we have performed electro-optical simulations of MW and BB based solar cells in order to calculate the effective optical shading factor, the enhancement of conversion efficiency and the saving of contact-paste, with respect to the BB design. Specifically, we have studied by means of a ray-tracing simulation tool the significant impact of the front contact grid geometry, of the encapsulation layer thickness and of the optical properties of the cell front interface on the effective optical shading. The calculated values of effective optical shading are used to determine the enhancement of the figures of merit and the paste saving with respect to the reference silver BB scheme. On the basis of our calculations the adoption of optimized MW designs may enhance the conversion efficiency up to 0.5% abs , allowing paste saving up to 50 mg per cell
The natural history of multiple osteochondromas in a large Italian cohort of pediatric patients.
Abstract Importance Multiple osteochondromas is a rare hereditary skeletal disorder, characterized by bony protrusions arising from growth plates on long bones during skeletal development. The disorder frequently leads to diminished stature, deformities and functional limitations. Understanding of the natural history of multiple osteochondromas and its evolution in children and adolescents is limited. Objective To provide valuable information on the natural history of multiple osteochondromas, to inform recommendations for treatment and prevent impairments caused by osteochondromas. Design This retrospective cohort study in children with multiple osteochondromas includes longitudinal data collected from first to last follow-up visit for patient demographics, and over 36 months for disease evolution. Setting Data were collected from the Registry of Multiple Osteochondromas, which includes data from circa 1200 patients with multiple osteochondromas treated from 2003 to 2017 at IRCCS Istituto Ortopedico Rizzoli in Bologna. Participants Patients ≤18 years with multiple osteochondromas, who provided written informed consent and had data for ≥1 12-month follow-up visit. Main outcome(s) and measurement(s) Demographics, clinical features, incidence of surgeries, and disease evolution (progression or regression) were assessed. Results were summarized using descriptive statistics, annual rates of new clinical features and surgeries, and Kaplan-Meier estimates. Patient height was evaluated following Italian growth charts. Results 158 patients were included in these analyses. Throughout follow-up, 80.4% of patients developed new osteochondromas, 57.6% developed new deformities, 23.4% developed new functional limitation(s). New osteochondroma(s) were developed by 28.5% patients by Month 12, 39.9% at Month 24, 50% at Month 36. Most new osteochondromas were detected in the younger population; patients aged 0–4 years underwent a significantly higher number of lesions within 12, 24 and 36 months of follow-up. The overall incidence of patients with ≥1 new deformity within 12 months was 17.7%, with incidences decreasing with increasing age (p = .023). In addition, the analyses on height highlight that 13 years is a cut off age for slow growth of the stature (p  Conclusions and relevance This natural history study reports the main set of clinically relevant data for patients with multiple osteochondromas during skeletal development, providing insight for patient management and development of therapeutic interventions
Adherence to therapeutic guidelines among patients treated with statins. Results from STAR study
INTRODUCTION: the objective of this study was to analyze adherence to therapeutic guidelines among patients treated with lipid lowering drugs (statins).MATERIAL AND METHODS: a retrospective observational study including 5 Local Health Units (LHUs) was conducted using administrative databases. Patients who received at least one prescription for statins between January 1st, 2007 and June 30th, 2008 were selected and followed for 12 months. Patients were classified according to their level of absolute cardiovascular risk (moderate, high, very high according to Nota 13 AIFA).RESULTS: a total of 71,855 patients were included (14,133 newly treated patients with statins, representing 19.4% of total sample), (age 68.8±10.7, male 51%). Level of absolute cardiovascular risk were: moderate risk (45.4%), high risk (33.4%), very high risk (16.3%), familial hypercholesterolemia (4.9%). Statins assumed by patients in analysis were stratified in two groups (first or second choice), accordingly to their efficacy (level of LDL cholesterol reduction) in relation to the patient’s cardiovascular risk (coherently with new Nota 13 AIFA, 2011). Among patients with a very high cardiovascular risk, only 52.8% used statins indicated by Nota13 as a first choice while 2.9% used a second choice statin and 44.3% used an inadequate statin and/or dosage; among familial hypercholesterolemia patients, those percentages were, respectively: 53.8%, 21.1% and 25.1%. When only patients naïve to statins treatment were analyzed, similar percentages were found. Only few patients in very high risk group used adequate dosages: among patients treated with rosuvastatin and atorvastatin, 11.2% used atorvastatin 40 mg, and 0.2% used atorvastatin 80 mg (this population was not analyzed for events because of low numerosity) while 4.1% used rosuvastatin 20 mg and 0.2% used rosuvastatin 40 mg; overall, 84.3% of patients in this group used inadequate dosages. Cardiovascular events at one year of follow up were 1.6% for patients treated with rosuvastatin 20 mg, 1.6% for rosuvastatin 40 mg and 6.1% for atorvastatin 40 mg; death rates (any cause) were 0.9%, 0.0%, 2.6% respectively. The analysis of the sub-population of patients treated with rosuvastatin 20 mg with previous CV event showed a percentage of patients with a CV event during the observational period of 3.4%, a percentage of patients with cerebrovascular event of 0.9% and a mortality percentage of 0.9%.Conclusions: in real practice setting, the percentage of patients prescribed for recommended statins and dosages is low
Epidemiology, patient profile, and health care resource use for hepatitis C in Italy
The objectives of this study were to estimate the prevalence of Hepatitis C among six Italian Local Health Units (LHUs), to describe patient and antiviral drug characteristics, and to estimate the health care consumption rates and related costs for the management of patients affected by hepatitis C virus (HCV) infection by using data from routine clinical practice
A Comparative Study of MWT Architectures by Means of Numerical Simulations
AbstractIn order to improve the efficiency of c-Si and mc-Si solar cells, Metal Wrap Though (MWT) architecture is investigated. In this paper we implement TCAD numerical simulations to analyze the performance of MWT cells with a point busbar or a continuous busbar at the back side. The two topologies of MWT cells are compared in both illuminated and dark conditions, aiming at understanding and comparing the resistive and recombination losses. The impact of the separation region is also studied, highlighting the degradation effect on the Fill Factor (FF) and on the efficiency in the two structures. We observe that the separation region dimension leads to a higher degradation of efficiency in case of continuous busbar
Healthcare Resources Use in Patients with Human Immunodeficiency Virus (HIV). Real-World Evidence From Six Italian Local Health Units
AIM: The aim of the study was to evaluate healthcare resource use and related costs for the management of people living with Human Immunodeficiency Virus (PLWHIV) with and without comorbidities, and to compare the burden of comorbidities in PLWHIV to the general population.METHODS: An observational retrospective analysis, based on administrative and laboratory databases from 6 Italian Local Health Units (LHUs) was performed. Individuals receiving either an HIV treatment [Antiretroviral therapy (ART) – ATC code: J05A)], or with an HIV positive laboratory test result between January 1st, 2014 and December 31st, 2014 were included. The date of first ART prescription or positive test of HIV was used as the Index Date (ID). Patients enrolled were followed-up for all time available from the ID (follow-up period) and their clinical characteristics were investigated from one year prior to the ID (characterization period). Comorbidities were measured by using the Charlson Comorbidity Index; findings were compared with those of a sample of the general population with the same age and sex distribution (OsMed 2015). Healthcare resource use and related cost was evaluated during the follow-up period.RESULTS: 1,214 patients were included, 837 were PLWHIV without any comorbidities and 377 were PLWHIV with at least one comorbidity. Mean prevalence of prescriptions for treatment of comorbidities was higher in the HIV-infected population than in the Italian general population. The annual healthcare cost of managing HIV patients with comorbidities, was significantly higher than that for patients without comorbidities (€ 10,615 vs. € 8,665, p < 0.001).CONCLUSIONS: Study results showed that 30% of PLWHIV had at least one comorbidity. The cost of managing PLWHIV who have comorbidities was significantly higher than that of managing PLWHIV without comorbidities. Our data confirm that care and treatment services should be adapted to address the specific needs of people living with both HIV and comorbidities
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