Gli hedge fund: caratteristiche, impatto sui mercati e ruolo nelle crisi finanziarie

Gli hedge fund (HF) sono sempre pi`u diffusamente considerati responsabili delle crisi finanziarie che si sono susseguite nel corso degli ultimi decenni. La loro natura di segretezza e la fama di particolare propensione al rischio, unite ad un ampio ricorso alla leva finanziaria, fanno si che questi operatori siano spesso indicati come principale causa dellaumento della volatilit`a ed instabilit`a dei mercati o quantomeno in grado di accentuarne fortemente le turbolenze. Per comprenderne correttamente il ruolo nelle situazioni di stress dei mercati, il lavoro ne analizza dapprima la natura e le caratteristiche distintive: principali strategie di investimento adottate, modalit`a di misurazione delle performance, struttura organizzativa tipica. Si esaminano poi i vantaggi che tipicamente la dottrina e la prassi riconoscono alla loro operativit` a: efficienza dei prezzi, liquidit`a dei mercati, innovazione innanzitutto. Si analizzano inoltre gli aspetti critici connessi allattivit degli HF, soprattutto in relazione alle situazioni di turbolenza dei mercati finanziari. Questa analisi `e essenziale per comprenderne il ruolo nellattuale crisi globale. Lo studio si conclude con alcune riflessioni sul dibattito che divide la comunit finanziaria circa lopportunit`a di introdurre misure specifiche di regolamentazione anche per lindustria degli HF

Analysis of aroma and polyphenolic compounds in Saperavi red wine vinified in Qvevri

The purpose of this study is to analyze and characterize a Georgian red wine from Saperavi grape, obtained in Qvevri (Georgian traditional winemaking method), by using innovative techniques for the determination of the polyphenolic content, aroma, and its correlation to the sensory characteristics. This peculiar red wine, after high‐performance liquid chromatography with diode‐array detection and mass spectrometry (HPLC‐DAD‐MS), headspace solid‐phase microextraction–gas chromatography–mass spectrometry (HS‐SPME‐GC‐MS), and HS‐SPME‐GCxGC‐MS/TOF (two‐dimensional gas chromatography) chemical characterization showed a high polyphenol content (19.6 × 10(2) mg/L, 38.4% anthocyanins) and a wide range of volatile compounds, among which terpenes were associated with the aroma of flowers, lemongrass, and wood. Analyses were also conducted to determine the total polyphenol content correlated to antioxidant activity with the Folin–Ciocalteu spectrophotometric in vitro method (4.650 g GAE/L). In conclusion, for the first time on Saperavi wine, innovative techniques such as HPLC‐DAD‐MS, GC‐MS, and GCxGC‐MS/TOF were simultaneously applied in association with the traditional analytic techniques to perform a complete chemical characterization. These activities are part of a project about circular viticulture in the Georgian territory that will lead the production of traced quality wines and the valorization of the Georgian wine sector

2016 Central Italy Earthquakes: comparison between GPS signals and low-cost distributed MEMS arrays

Abstract. Modern seismic ground-motion sensors have reached an excellent performance quality in terms of dynamic range and bandwidth resolution. The weakest point in the recording of seismic events remains spatial sampling and spatial resolution, due to the limited number of installed sensors. A significant improvement in spatial resolution can be achieved by the use of non-conventional motion sensors, such as low-cost distributed sensors arrays or positioning systems, capable of increasing the density of classical seismic recording networks. In this perspective, we adopted micro-electro mechanical system (MEMS) sensors to integrate the use of standard accelerometers for moderate-to-strong seismic events. In addition, we analyse high-rate distributed positioning system data that also record soil motion. In this paper, we present data from the 2016 Central Italy earthquakes as recorded by a spatially dense prototype MEMS array installed in the proximity of the epicentral area, and we compare the results to the signal of local 1s GPS stations. We discuss advantages and limitations of this joint approach, reaching the conclusion that such low-cost sensors and the use of high rate GPS signal could be an effective choice for integrate the spatial density of stations providing strong-motion parameters

Thymic output generates a new and diverse TCR repertoire after autologous stem cell transplantation in multiple sclerosis patients

Clinical trials have indicated that autologous hematopoietic stem cell transplantation (HSCT) can persistently suppress inflammatory disease activity in a subset of patients with severe multiple sclerosis (MS), but the mechanism has remained unclear. To understand whether the beneficial effects on the course of disease are mediated by lympho-depletive effects alone or are sustained by a regeneration of the immune repertoire, we examined the long-term immune reconstitution in patients with MS who received HSCT. After numeric recovery of leukocytes, at 2-yr follow-up there was on average a doubling of the frequency of naive CD4+ T cells at the expense of memory T cells. Phenotypic and T cell receptor excision circle (TREC) analysis confirmed a recent thymic origin of the expanded naive T cell subset. Analysis of the T cell receptor repertoire showed the reconstitution of an overall broader clonal diversity and an extensive renewal of clonal specificities compared with pretherapy. These data are the first to demonstrate that long-term suppression of inflammatory activity in MS patients who received HSCT does not depend on persisting lymphopenia and is associated with profound qualitative immunological changes that demonstrate a de novo regeneration of the T cell compartment

Patient safety in care circumstances: prevention of adverse events in the hospitalization of children

This case study with a qualitative approach presents an analysis of the perceptions of family caregivers/companions and health workers concerning adverse events in care contexts. A total of 15 companions and 23 health workers from pediatric hospitalization units of a university hospital in Porto Alegre, Brazil participated in this study from August to December 2010. Data were collected through semi-structured interviews and analyzed through thematic content analysis using QSR's Nvivo version 7.0. Seven thematic categories emerged from the analysis. The results highlight reviewing and checking workers' interventions and implementing effective communication among workers, caregivers and children. The main recommendations concern changing the organizational culture of health facilities, emphasizing safe care and a systemic view of the evaluation of adverse events.Se trata de una investigación estudio de caso cualitativo, cuyo objetivo fue analizar cómo las acompañantes/cuidadoras y profesionales de salud reconocen los eventos adversos en las circunstancias de cuidado. Fue realizada con 15 acompañantes/cuidadores y 23 profesionales de salud de las unidades de internación de pediatría de un hospital-escuela de Porto Alegre, Brasil entre agosto y diciembre de 2010. Entrevista semi-estructurada fue utilizada para la recolección de las informaciones, siendo sometidas a análisis temático con apoyo del software QSR Nvivo 7.0. El análisis de las informaciones dejó en evidencia siete categorías. Los resultados sugieren la revisión y control permanente en cualquier intervención del profesional y el proceso de comunicación efectivo profesional-acompañante-niño. El estudio trae como recomendaciones los cambios en la cultura organizacional de las instituciones de salud para una cultura de seguridad, con énfasis en el cuidado seguro y visión sintética en la evaluación de la ocurrencia de eventos adversos.Trata-se de pesquisa de abordagem qualitativa do tipo estudo de caso, cujo objetivo foi analisar como as acompanhantes/cuidadoras e profissionais da saúde reconhecem os eventos adversos nas circunstâncias de cuidado. Foi realizada com 15 acompanhantes/cuidadores e 23 profissionais da saúde das unidades de internação pediátrica de um hospital-escola de Porto Alegre, RS, Brasil, no período entre agosto e dezembro de 2010. A entrevista semiestruturada foi utilizada na coleta das informações, sendo submetida à técnica da análise temática com apoio do software QSR Nvivo, versão 7.0. A análise das informações evidenciou sete categorias temáticas. Nos resultados, destacam-se a revisão e conferência permanentes em qualquer intervenção do profissional e o processo de comunicação efetivo profissional/acompanhante/criança. O estudo traz como principais recomendações as mudanças na cultura organizacional das instituições de saúde para uma cultura de segurança, com ênfase no cuidado seguro em saúde e visão sistêmica na avaliação da ocorrência de eventos adversos

Transplantation of Specific Human Astrocytes Promotes Functional Recovery after Spinal Cord Injury

Repairing trauma to the central nervous system by replacement of glial support cells is an increasingly attractive therapeutic strategy. We have focused on the less-studied replacement of astrocytes, the major support cell in the central nervous system, by generating astrocytes from embryonic human glial precursor cells using two different astrocyte differentiation inducing factors. The resulting astrocytes differed in expression of multiple proteins thought to either promote or inhibit central nervous system homeostasis and regeneration. When transplanted into acute transection injuries of the adult rat spinal cord, astrocytes generated by exposing human glial precursor cells to bone morphogenetic protein promoted significant recovery of volitional foot placement, axonal growth and notably robust increases in neuronal survival in multiple spinal cord laminae. In marked contrast, human glial precursor cells and astrocytes generated from these cells by exposure to ciliary neurotrophic factor both failed to promote significant behavioral recovery or similarly robust neuronal survival and support of axon growth at sites of injury. Our studies thus demonstrate functional differences between human astrocyte populations and suggest that pre-differentiation of precursor cells into a specific astrocyte subtype is required to optimize astrocyte replacement therapies. To our knowledge, this study is the first to show functional differences in ability to promote repair of the injured adult central nervous system between two distinct subtypes of human astrocytes derived from a common fetal glial precursor population. These findings are consistent with our previous studies of transplanting specific subtypes of rodent glial precursor derived astrocytes into sites of spinal cord injury, and indicate a remarkable conservation from rat to human of functional differences between astrocyte subtypes. In addition, our studies provide a specific population of human astrocytes that appears to be particularly suitable for further development towards clinical application in treating the traumatically injured or diseased human central nervous system

Epstein-Barr Virus Stimulates Torque Teno Virus Replication: A Possible Relationship to Multiple Sclerosis

Viral infections have been implicated in the pathogenesis of multiple sclerosis. Epstein-Barr virus (EBV) has frequently been investigated as a possible candidate and torque teno virus (TTV) has also been discussed in this context. Nevertheless, mechanistic aspects remain unresolved. We report viral replication, as measured by genome amplification, as well as quantitative PCR of two TTV-HD14 isolates isolated from multiple sclerosis brain in a series of EBV-positive and -negative lymphoblastoid and Burkitt's lymphoma cell lines. Our results demonstrate the replication of both transfected TTV genomes up to day 21 post transfection in all the evaluated cell lines. Quantitative amplification indicates statistically significant enhanced TTV replication in the EBV-positive cell lines, including the EBV-converted BJAB line, in comparison to the EBV-negative Burkitt's lymphoma cell line BJAB. This suggests a helper effect of EBV infections in the replication of TTV. The present study provides information on a possible interaction of EBV and TTV in the etiology and progression of multiple sclerosis