Positive Solutions For a Schr\"odinger-Bopp-Podolsky system in R3\mathbb R^{3}

We consider the following Schr\"odinger-Bopp-Podolsky system in $\mathbb R^{3}$ $$\left\{ \begin{array}{c} -\varepsilon^{2} \Delta u + V(x)u + \phi u = f(u)\\ -\varepsilon^{2} \Delta \phi + \varepsilon^{4} \Delta^{2}\phi = 4\pi u^{2}\\ \end{array} \right.$$ where $\varepsilon > 0$ with $V:\mathbb{R}^{3} \rightarrow \mathbb{R}, f:\mathbb{R} \rightarrow \mathbb{R}$ satisfy suitable assumptions. By using variational methods, we prove that the number of positive solutions is estimated below by the Ljusternick-Schnirelmann category of $M$, the set of minima of the potential $V$

WHAT IS THE FATE OF TRADE UNIONS IN ITALY? RESULTS OF A TRAINING COURSE ADDRESSED TO THE EXECUTIVE BOARD

With the rising of technology, occupations will have to face growth, reduction or redesign: therefore, changes in organizations, human capital and processes involving people will occur. We focus on the main Trade Union operating in Italy. At first, we present an analysis of this organization. Then, we describe a training course addressed to a sample of Trade Union Executive Board. Finally, we provide suggestions about some possible development scenarios. As a result, we may underline three critical issues: a) People minimize the potential effects of automation on jobs and on their own career and they are not prepared to this change; 2) The organization is losing its bargaining power and risks to disappear, leaving a gap in the intermediary function between the employer and the employees; 3) The Executive Board fails in making forecasts and strategic planning, to effectively negotiate with the employer. The main output of the course is a Project Work which contains a description of a strategic intervention which could be implemented in the organization to effectively deal with the future changes

Evaluating the spatial heterogeneity of innovation drivers: a comparison between GWR and GWPR

In studies focusing on innovation activities, the potential spatial heterogeneity in the relationships between innovation and its triggering factors is an unexplored topic. On this ground, this paper aims to a twofold contribution. First, we verify the existence of spatial variability in the relationships. We evaluate the estimation gains due to local regressions, such as geographically weighted regression (GWR) and geographically weighted panel regression (GWPR), with respect to the classical global methods (e.g., OLS, Fixed Effects panel regression). Second, we compare the GWPR with GWR and global models to evaluate if the joint consideration of time and space dimensions allows for the rise of new insights. We resort to official data on 287 NUTS-2 European regions in 2014–2021. The results confirm that GWPR estimations significantly differ from GWR and global models, potentially producing new patterns and findings

Guiding light via geometric phases

Known methods for transverse confinement and guidance of light can be grouped into a few basic mechanisms, the most common being metallic reflection, total internal reflection and photonic-bandgap (or Bragg) reflection. All of them essentially rely on changes of the refractive index, that is on scalar properties of light. Recently, processes based on "geometric Berry phases", such as manipulation of polarization states or deflection of spinning-light rays, have attracted considerable interest in the contexts of singular optics and structured light. Here, we disclose a new approach to light waveguiding, using geometric Berry phases and exploiting polarization states and their handling. This can be realized in structured three-dimensional anisotropic media, in which the optic axis lies orthogonal to the propagation direction and is modulated along it and across the transverse plane, so that the refractive index remains constant but a phase distortion can be imposed on a beam. In addition to a complete theoretical analysis with numerical simulations, we present a proof-of-principle experimental demonstration of this effect in a discrete element implementation of a geometric phase waveguide. The mechanism we introduce shows that spin-orbit optical interactions can play an important role in integrated optics and paves the way to an entire new class of photonic systems that exploit the vectorial nature of light.Comment: Publication supported by European Union (EU) within Horizon 2020 - ERC-Advanced Grant PHOSPhOR, grant no. 694683. This is the final peer-reviewed manuscript as accepted for publication (including methods and supplementary information

Chronic HBV infection in pregnant immigrants: a multicenter study of the Italian Society of Infectious and Tropical Diseases

The aims of the study were to estimate the clinical impact of HBV infection in pregnant immigrants and their family members and to identify a useful approach to managing the healthcare of HBsAg-positive immigrants. Included in this study were 143 HBsAg-positive pregnant immigrants of the 1,970 from countries with intermediate/high HBV endemicity who delivered in 8 Italian hospitals in 2012-2013. In addition, 172 family members of 96 HBsAg-positive pregnant immigrants were tested for serum HBsAg. The median age of the 143 HBsAg-positive pregnant immigrants was 31.0±12.1 years and the length of stay in Italy 5.0±4.1 years; 56.5% were unaware of their HBsAg positivity. HBV DNA was detected in 74.5% of the pregnant immigrants, i.e., 94.3% from Eastern Europe, 72.2% from East Asia and 58.1% from Sub-Saharan Africa. HBV DNA ≥2000 IU/mL was detected in 47.8% of pregnant immigrants, associated with ALT ≥1.5 times the upper normal value in 15% of cases. Anti-HDV was detected in 10% of cases. HBsAg was detected in 31.3% of the 172 family members. All HBsAg-positive immigrants received counseling on HBV infection and its prevention, and underwent a complete clinical evaluation. The findings validate the approach used for the healthcare management of the HBsAg-positive immigrant population

Length–weight relationships for some plecoptera and ephemeroptera from a carbonate stream in central Apennine (Italy)

The relationship between dry weight and body length for larvae of Plecoptera (Leuctra spp., Isoperla grammatica, Nemoura cinerea) and Ephemeroptera (Baetis spp., Habrophlebia fusca, Paraleptophlebia submarginata, Ecdyonurus helveticus, Rhithrogena semicolorata), collected from a carbonate stream in the Apennine (central Italy), is reported. The power equation f(x) = Ax B has been applied to fit the curves of dry weight vs. body size (length) in the ranges 0.03–13.00 mg and 2–14 mm, respectively; a total of 674 larvae were examined. The power model was in very good agreement with experimental data. Moreover, the error between measured and estimated weight was in the 4–20% range. The data on Isoperla grammatica, Leuctra spp., Rhithrogena semicolorata and Baetis spp. were compared to those in a previous study in a different geographical setting (south-western Germany's Black Forest) obtaining similar results but with lower errors. We used and compared two methods: the weighted least-square method (WLS) and an analysis of covariance (ANCOVA). The values of the A and B coefficients obtained with the two methods were very similar (<6% discrepancy for either A or B). We found the best fits for all the examined Plecoptera (species, genus, and order level), while the results for Ephemeroptera were varied, with loose fits at the order level and also for Leptophlebiidae collectively considered

A General Framework for Hierarchical Redundancy Resolution Under Arbitrary Constraints

The increasing interest in autonomous robots with a high number of degrees of freedom for industrial applications and service robotics demands control algorithms to handle multiple tasks as well as hard constraints efficiently. This paper presents a general framework in which both kinematic (velocity- or acceleration-based) and dynamic (torque-based) control of redundant robots are handled in a unified fashion. The framework allows for the specification of redundancy resolution problems featuring a hierarchy of arbitrary (equality and inequality) constraints, arbitrary weighting of the control effort in the cost function and an additional input used to optimize possibly remaining redundancy. To solve such problems, a generalization of the Saturation in the Null Space (SNS) algorithm is introduced, which extends the original method according to the features required by our general control framework. Variants of the developed algorithm are presented, which ensure both efficient computation and optimality of the solution. Experiments on a KUKA LBRiiwa robotic arm, as well as simulations with a highly redundant mobile manipulator are reported.Comment: 19 pages, 19 figures, submitted to the IEE

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