Forecasting output growth tail risk using quantile regression framework

This thesis examines which financial indicator is the most accurate to model and predict the tail risk of output growth in the euro area. The CISS is more informative than other indicators that only focus on specific segment of the financial market. To capture the tail distribution information, the thesis implements quantile regression, capturing determined quantile of the output growth distribution. The forecast produced with the quantile regression for the 10th and the 5th quantile outperformed the standard OLS model in terms of forecasting evaluation metrics in predicting the 2008 output growth downfall, concluding that the quantile specification, combined with the CISS as financial indicator, improves the modeling and forecasting accuracy of tail risk output growth in the euro area

The Athlete's Heart in Adolescent Africans An Electrocardiographic and Echocardiographic Study

ObjectivesThe goal of this study was to define electrocardiographic (ECG) and echocardiographic characteristics of adolescent African athletes.BackgroundRecent observations in African athletes reported large prevalence of left ventricular (LV) hypertrophy and ECG abnormalities. No data, so far, exist for adolescent Africans, which comprise a growing proportion of competitive/professional athletes.MethodsThe study included 154 soccer players participating at the 8th African Under-17 Championship of 2009, representing Algeria, Burkina Faso, Cameroon, Gambia, Guinea, Malawi, Nigeria, and Zimbabwe. For comparison, 62 Italian players with similar ages, sport achievements, and training schedules were included.ResultsAfrican athletes showed higher R5/S1-wave voltages than Caucasian athletes (48.6 ± 12.1 mm vs. 34.1 ± 8.9 mm; p < 0.01), larger prevalence of ECG LV hypertrophy (89% vs. 42%; p < 0.001), ST-segment elevation (91% vs. 56%; p < 0.001), and deeply inverted, or diffusely flat/biphasic, T waves (14% vs. 3% [p < 0.05] and 25% vs. 8% [p < 0.008], respectively). LV wall thicknesses were increased in Africans by 5% compared with Caucasians, and exceeded normal limits (≥13 mm) in 4 Africans but in no Caucasians. No athlete showed evidence of cardiomyopathies (i.e., hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy). On individual analysis, Algerians showed lower R/S-wave voltages compared with other African athletes. Increased wall thickness (≥13 mm) was observed only in sub-Saharian athletes (from Burkina Faso, Cameroon, and Niger).ConclusionsAfrican athletes displayed large proportion of ECG abnormalities, including a striking increase in R/S-wave voltage, ST-segment elevation, and deeply inverted or diffusely flat T waves by adolescence. LV remodeling in African athletes was characterized by a disproportionate wall thickening than in Caucasians but similar cavity size. Finally, distinctive peculiarities existed in African athletes according to the country (and ethnic) origin

Long-Term Clinical Consequences of Intense, Uninterrupted Endurance Training in Olympic Athletes

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DDIT4/REDD1/RTP801 is a novel negative regulator of schwann cell myelination

Signals that promote myelination must be tightly modulated to adjust myelin thickness to the axonal diameter. In the peripheral nervous system, axonal neuregulin 1 type III promotes myelination by activating erbB2/B3 receptors and the PI3K/AKT/mTOR pathway in Schwann cells. Conversely, PTEN (phosphatase and tensin homolog on chromosome 10) dephosphorylates PtdIns(3,4,5)P3and negatively regulates the AKT pathway and myelination. Recently, the DLG1/SAP97 scaffolding protein was described to interact with PTEN to enhance PIP3dephosphorylation. Here we now report that nerves from mice with conditional inactivation of Dlg1 in Schwann cells display only a transient increase in myelin thickness during development, suggesting that DLG1 is a transient negative regulator of myelination. Instead, we identified DDIT4/RTP801/REDD1 as a sustained negative modulator of myelination. We show that DDIT4 is expressed in Schwann cells and its maximum expression level precedes the peak of AKT activation and of DLG1 activity in peripheral nerves. Moreover, loss of DDIT4 expression both in vitro and in vivo in Ddit4-null mice provokes sustained hypermyelination and enhanced mTORC1 activation, thus suggesting that this molecule is a novel negative regulator of PNS myelination

Neuronal models of TDP-43 proteinopathy display reduced axonal translation, increased oxidative stress, and defective exocytosis

Amyotrophic lateral sclerosis (ALS) is a progressive, lethal neurodegenerative disease mostly affecting people around 50–60 years of age. TDP-43, an RNA-binding protein involved in pre-mRNA splicing and controlling mRNA stability and translation, forms neuronal cytoplasmic inclusions in an overwhelming majority of ALS patients, a phenomenon referred to as TDP-43 proteinopathy. These cytoplasmic aggregates disrupt mRNA transport and localization. The axon, like dendrites, is a site of mRNA translation, permitting the local synthesis of selected proteins. This is especially relevant in upper and lower motor neurons, whose axon spans long distances, likely accentuating their susceptibility to ALS-related noxae. In this work we have generated and characterized two cellular models, consisting of virtually pure populations of primary mouse cortical neurons expressing a human TDP-43 fusion protein, wt or carrying an ALS mutation. Both forms facilitate cytoplasmic aggregate formation, unlike the corresponding native proteins, giving rise to bona fide primary culture models of TDP-43 proteinopathy. Neurons expressing TDP-43 fusion proteins exhibit a global impairment in axonal protein synthesis, an increase in oxidative stress, and defects in presynaptic function and electrical activity. These changes correlate with deregulation of axonal levels of polysome-engaged mRNAs playing relevant roles in the same processes. Our data support the emerging notion that deregulation of mRNA metabolism and of axonal mRNA transport may trigger the dying-back neuropathy that initiates motor neuron degeneration in ALS

Energy balance and dietary habits in America's Cup sailors.

This research, which was conducted with crew members of an America's Cup team, had the following objectives: (a) to assess energy expenditure and intake during training; (b) to evaluate the sailors' diet, and (c) to identify any dietary flaws to determine the appropriate intake of nutrients, correct possible dietary mistakes, and improve their food habits. Energy expenditure was estimated on 15 sailors using direct measurements (oxygen consumption) and a 3-day activity questionnaire. Oxygen consumption was measured on sailors during both on-water America's Cup sailing training and dry-land fitness training. Composition of the diet was estimated using a 3-day food record. Average daily energy expenditure of the sailors ranged from 14.95 to 24.4 MJ, depending on body mass and boat role, with the highest values found in grinders and mastmen. Daily energy intake ranged from 15.7 to 23.3 MJ (from +6% to - 18% of energy expenditure). The contributions of carbohydrate, protein, and fat to total energy intake were 43%, 18%, and 39% respectively, values that are not in accord with the recommended guidelines for athletes. Our results show the importance of assessing energy balance and food habits for America's Cup sailors performing different roles. The practical outcome of this study was that the sailors were given dietary advice and prescribed a Mediterranean diet, explained in specific nutrition lectures

Physiological Characteristics of America’s Cup Sailors.

The aim of this study was to assess the physiological profile of America's Cup grinders and mastmen, by measuring energy expenditure during sailing and assessing their aerobic and anaerobic fitness. The study focused on estimating the energy used during grinding activity, by measuring oxygen uptake (VO2) during sail setting in real sailing conditions. In the laboratory, using an arm-cranking ergometer, we measured VO2peak during an incremental maximal exercise test and total energy expended during the effort and recovery phases of an all-out test that simulated grinding activity, in six grinders and mastmen and ten sailors of the same crew. Total energy used during grinding corresponded to 45% (s = 9) and 51% (s = 5) of that used in the all-out test (234 kJ, s = 21.7) for tacks and gybes, respectively. In both grinding activity and the all-out test, VO2 increased during and after the effort. The "VO2 top value" was 53% (s = 8.6), 68% (s = 5.5), and 78% (s = 3. 1) of VO2peak (4.7 1 center dot min(-1), s = 0.43) in tacks, gybes, and the all-out test, respectively. Puring fast sequences of grinding activity, the "VO2 top value" reached 65% (s = 7. 1) VO2peak in tacks and 91% (s = 3.3) VO2peak in gybes. Our results suggest that grinders and mastmen are characterized by a high anaerobic capacity but their performance can be improved by powering aerobic fitness, to increase this energy contribution to all-out efforts and to guarantee fast recovery when grinding activity is repeated with short rest intervals