Turbulence underneath the big calm? The micro-evidence behind Italian productivity dynamics

Italy ranked last in terms of manufacturing productivity growth according to OECD estimates over the last decade, with a flat, if not declining, trend. In this work we investigate the underlying firm-level dynamics of enterprises on the basis of a database developed by the Italian Statistical Office (ISTAT) covering the period 1989–2004 and containing information on more than 100,000 firms. Over this period not only have the indicators of the central tendency of the distribution of labor productivity not significantly changed, but also the whole sectoral distributions have remained relatively stable over time, with their support at least not shrinking, or even possibly widening, over time. This is even more surprising if one takes into consideration the “Euro” shock that occurred during the period investigated. On the contrary, we observe that inter-decile differences in productivity have been increasing. Further, heterogeneous firms’ characteristics (i.e. export activity and innovation) seem to have contributed to boosting such intra-industry differences. Given such wide heterogeneities we resort to quantile regressions to identify the impact of a set of regressors at different levels of the conditional distribution of labor productivity. One phenomenon that we observe is what we call a tendency toward “neo-dualism” involving the co-existence of a small group of dynamic firms with a bigger ensemble of much less technologically progressive ones

An innovative approach for migraine prevention in young age: a preliminary study

Headache is one of the commonest conditions to affect children and adolescents in industrialized countries. Effective pharmacological treatments without side effects are still lacking. Ginkgolide B, an herbal constituent extract from ginkgo biloba tree leaves, is a natural antiplatelet activating factor (PAF). PAF is a potent proinflammatory and nociceptive agent released during the inflammation process. Therefore, Ginkgolide B can be considered a promising non-pharmacological tool for treatment of migraine with and without aura. We propose to determine the efficacy of Ginkgolide B as preventive treatment in a group of young patients suffering from migraine without aura. A small sample of 24 young patients suffering from migraine without aura entered the open-label prospective trial. Migraine without aura was diagnosed according to International Headache Society criteria. The treatment was well tolerated and the compliance was good. These preliminary data show that Ginkgolide B seems to be effective as preventive treatment in reducing migraine attack frequency and in attenuating the use of symptomatic medication in our small series of children with primary headache

Exercise Intervention to Improve Functional Capacity in Older Adults After Acute Coronary Syndrome

More than one-half of patients admitted for acute coronary syndrome (ACS) are age $70 years. Mobility limitations and sedentary behavior are common in older ACS patients and contribute to high risk of recurrence and mortality (1). Although older ACS patients may benefit the most from participation in exercise-based cardiac rehabilitation/secondary prevention programs (CR/SP), they are less likely to participate in such programs (2). Whether an early, individualized, and low-cost physical activity (PA) intervention including a few supervised sessions and a home-based program might be feasible and effective for improving functional capacity in this high-risk and undertreated population is unknown. The HULK (Physical Activity Intervention for Patients With Reduced Physical Performance After Acute Coronary Syndrome; NCT03021044) trial is a multicenter, randomized clinical trial. A detailed study outline and statistical plan have been previously published (3). Inclusion criteria were age$70 years, hospitalization for ACS, and Short Physical Performance Battery (SPPB) score between 4 and 9 at the inclusion visit (30 5 days after hospital discharge). The SPPB is a scale that combines gait speed, chair stand, and balance tests. It ranges from 0 (worst) to 12 (best) and has predictive validity for mortality (4). Participants were randomized to usual care and health education (control group) or usual care and PA intervention (intervention group). The control group received a 20-min session and a detailed brochure stressing the importance of PA in cardiovascular health. The PA intervention consisted of four supervised sessions (1, 2, 3, and 4 months after hospital discharge), combined with an individualized home-based PA program. Centerbased sessions included a moderate standardized treadmill-walk, strength, and balance exercises (3). After the practice sessions, patients received a tailored PA home program (3). Weekly energy expenditure from PA was determined by a selfreported 7-day physical activity recall (kcal/week), and objectively measured by wearing an accelerometer (min/week). The primary endpoint was the 6- month SPPB. Secondary endpoints were 1-year SPPB and time engaged in PA. From January 2017 to April 2018, 235 patients were randomized (n ¼ 117, control group; n ¼ 118, intervention group). The median age was 76 (interquartile range [IQR]: 73 to 81) years, and 23% were female. Before the hospitalization, light and moderateintensive PA was performed by 66% and 14% of patients, respectively. Baseline characteristics, as well as baseline SPPB value (Figure 1), did not differ between groups. The adherence rates of the PA intervention group to the 1-, 2-, 3-, and 4-month scheduled supervised sessions were 100%, 89%, 85%, and 72%, respectively. The time engaged in PA progressively and significantly increased in the intervention group (Figure 1). At 6 months, the SPPB score was significantly higher in the intervention group (median: 9 [IQR: 8 to 11] vs. 7 [IQR: 5 to 8]; p < 0.001) (Figure 1). This improvement was supported by a significant increase in SPPB components of walking and chair rise (balance remained unchanged). The number of patients showing an increase of at least 1 point in SPPB score was 86 (74%) in the intervention group versus 46 (40%) in the control group (p < 0.001). The SPPB increase was maintained at the 1-year visit (Figure 1) and independent of sex and educational status. Typical CR/SP includes 3 weekly supervised exercise and educational sessions for 12 weeks. Despite the health benefits associated with these interventions, few eligible patients are referred or complete such programs (1). Our novel PA intervention was designed to address this issue. The attendance rate was high (72% [95% confidence interval: 64% to 80%]). The average weekly energy expenditure from PA in the intervention group increased 3.4 times, and SPPB score showed a mean increment of 2.0 points. This finding is notable given that an SPPB improvement of 1.0 point is generally considered a substantial clinically meaningful change (2). In addition, despite the absence of supervised sessions after the sixth month, the achievements were maintained until 1-year visit. If confirmed in future studies, our PA intervention model might help to mitigate the challenges related to limited health care resources and might increase the number of older adults receiving CR/SP

A moderate 500-m treadmill walk for estimating peak oxygen uptake in men with NYHA class I-II heart failure and reduced left ventricular ejection fraction

Background: Maximal cardiopulmonary exercise testing (CPX) is the gold-standard for cardiorespiratory fitness assessment in chronic heart failure (CHF) patients. However, high costs, required medical supervision, and safety concerns make maximal exercise testing impractical for evaluating mobility-impaired adults. Thus, several submaximal walking protocols have been developed and currently used to estimate peak oxygen consumption (VO(2)peak)in CHF patients. However, these tests have to be performed at close to maximum exercise intensity. The aim of this study was to examine the validity of a 500-m treadmill-walking test carried out at moderate intensity for estimating VO(2)peak in community-dwelling adult and elderly patients with CHF and reduced left ventricular ejection fraction (HFrEF).Methods: Forty-three clinically stable men with HFrEF (age 67.7 +/- 9.2 years, and left ventricular ejection fraction, LVEF 38% +/- 6%) underwent exercise testing during an outpatient cardiac rehabilitation/secondary prevention program. Each patients completed a CPX, and a moderate and self-paced (11-13/20 on the Borg scale) 500-m treadmill-walking test. Age, weight, height, walk time, and heart rate during the 500-m test were entered into prediction equations previously validated for VO(2)peak estimation from a 1000-m walking test in patients with cardiovascular disease and preserved LVEF.Results: Directly measured and estimated VO(2)peak values were not different (21.6 +/- 4.9 vs 21.7 +/- 4.6 mL/kg/min). The comparison between measured and estimated VO(2)peak values yielded a correlation of R = 0.97 (SEE = 0.7 mL/kg/min, P < 0.0001). The slope and the intercept coincided with the line of identity (Passing and Bablock analysis, P = 0.50). Residuals were normally distributed, and the examination of the Bland-Altman analysis do not show systematic or proportional error.Conclusions: A moderate and self-regulated 500-m treadmill-walking test is a valid tool for VO(2)peak estimation in patients with HFrEF. These findings may have practical implications in the context of transitioning from clinically based programs to fitness facilities or self-guided exercise programs in adults and elderly men with HFrEF

No efficacy of transcranial direct current stimulation on chronic migraine with medication overuse : a double blind, randomised clinical trial

Background: Transcranial direct current stimulation was suggested to provide beneficial effects in chronic migraine, a condition often associated with medication overuse for which no long-term therapy is available. Methods: We conducted a randomised controlled trial to assess long-term efficacy of transcranial direct current stimulation. Adults diagnosed with chronic migraine and medication overuse were assigned to receive in a 1:1:1 ratio anodal, cathodal, or sham transcranial direct current stimulation daily for five consecutive days, along with standardised drug withdrawal protocol. Primary outcome was 50% reduction of days of headache per month at 12 months. Co-secondary outcomes were 50% reduction of days of headache per month at 6 months, reduction of analgesic intake per month, and change in disability and quality of life, catastrophising, depression, state and trait anxiety, dependence attitude and allodynia intensity. Patients were not allowed to take any migraine prophylaxis drug for the entire study period. Results: We randomly allocated 135 patients to anodal (44), cathodal (45), and sham (46) transcranial direct current stimulation. At 6 and 12 months, the percentage of reduction of days of headache and number of analgesics per month ranged between 48.5% and 64.7%, without differences between transcranial direct current stimulation (cathodal, anodal, or the results obtained from the two arms of treatment, anodal plus cathodal) and sham. Catastrophising attitude significantly reduced at 12 months in all groups. There was no difference for the other secondary outcomes. Conclusions: Transcranial direct current stimulation did not influence the short and long-term course of chronic migraine with medication overuse after acute drug withdrawal. Behavioral and educational measures and support for patients' pain management could provide long-term improvement and low relapse rate. Trial registration number NCT04228809

Learning-to-Learn Stochastic Gradient Descent with Biased Regularization

We study the problem of learning-to-learn: inferring a learning algorithm that works well on tasks sampled from an unknown distribution. As class of algorithms we consider Stochastic Gradient Descent on the true risk regularized by the square euclidean distance to a bias vector. We present an average excess risk bound for such a learning algorithm. This result quantifies the potential benefit of using a bias vector with respect to the unbiased case. We then address the problem of estimating the bias from a sequence of tasks. We propose a meta-algorithm which incrementally updates the bias, as new tasks are observed. The low space and time complexity of this approach makes it appealing in practice. We provide guarantees on the learning ability of the meta-algorithm. A key feature of our results is that, when the number of tasks grows and their variance is relatively small, our learning-to-learn approach has a significant advantage over learning each task in isolation by Stochastic Gradient Descent without a bias term. We report on numerical experiments which demonstrate the effectiveness of our approach

Neutron Tomography at INES: First experimental results

A neutron tomography apparatus has been designed and installed at the Italian neutron experimental station (INES) at ISIS (UK). The instrument has a double aim: an additional opportunity for the INES users and a “bench test” for an instrument component that will be proposed for installation on some of the new neutron scattering instruments of Target Station 2 (TS2) of ISIS. Here, we present the first experimental results achieved with this apparatus

“Simultaneous and integrated neutron-based techniques for material analysis of a metallic ancient flute“

A metallic 19th century flute was studied by means of integrated and simultaneous neutron-based techniques: neutron diffraction, neutron radiative capture analysis and neutron radiography. This experiment follows benchmark measurements devoted to assessing the effectiveness of a multitask beamline concept for neutron-based investigation on materials. The aim of this study is to show the potential application of the approach using multiple and integrated neutron-based techniques for musical instruments. Such samples, in the broad scenario of cultural heritage, represent an exciting research field. They may represent an interesting link between different disciplines such as nuclear physics, metallurgy and acoustics