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Is the gender gap still a topic in the academic world and in particular in Science, Technology, Engineering, and Mathematics (STEM)? What difficulties did women who pursue a career in academia have to overcome? What are the differences among countries and what has changed compared to the past? As women and members of a community of young researchers in Operations Research (OR), we have tried to find answers to these questions by interviewing a group of prominent female professors and affirmed researchers in STEM belonging to different generations, with dissimilar careers and experiences. We have discussed with them about awareness, leaky pipelines, mobility, mentoring, society, role of education, and more. Their motivating stories and opinions contained in this article have allowed us to extrapolate a portrait of what barriers women encountered in STEM in the past, but also what challenges and stereotypes are still to be overcome, striving to close the gap.

Sustainability 13(8), 4362 (2021). doi:10.3390/su13084362 special issue: "Special Issue "Sustainability in Synchromodal Logistics and Transportation" / Special Issue Editors : Dr. Daniele Manerba, Guest Editor; Prof. Dr. An Caris, Guest Editor", Published by MDPI, Basel

Interstitial lung disease (ILD) encompasses a wide range of parenchymal lung pathologies with different clinical, histological, radiological, and serological features. Follow-up, treatment, and prognosis are strongly influenced by the underlying pathogenesis. Considering that an ILD may complicate the course of any connective tissue disease (CTD) and that CTD's signs are not always easily identifiable, it could be useful to screen every ILD patient for a possible CTD. The recent definition of interstitial pneumonia with autoimmune features is a further confirmation of the close relationship between CTD and ILD. In this context, the multidisciplinary approach is assuming a growing and accepted role in the correct diagnosis and follow-up, to as early as possible define the best therapeutic strategy. However, despite clinical advantages, until now, the pathways of the multidisciplinary approach in ILD patients are largely heterogeneous across different centers and the best strategy to apply is still to be established and validated. Aims of this article are to describe the organization of our multidisciplinary group for ILD, which is mainly focused on the early identification and management of CTD in patients with ILD and to show our results in a 1 year period of observation. We found that 15% of patients referred for ILD had an underlying CTD, 33% had interstitial pneumonia with autoimmune feature, and 52% had ILD without detectable CTD. Furthermore, we demonstrated that the adoption of a standardized strategy consisting of a screening questionnaire, specific laboratory tests, and nailfold videocapillaroscopy in all incident ILD proved useful in making the right diagnosis.

AIROYoung is the Young Researchers Chapter of AIRO (Italian Association of Operations Research). In this work, we focus on the AIROYoung Workshop, an annual event which has been reuniting young researchers constituting this community from 2017. Describing all the editions of the initiative, we highlight the main guidelines we have been following so far to organize it (e.g., no registration fee, grants for free accommodation, no parallel sessions, and a look to sustainability). We analyze surveys filled by participants to present qualitative and quantitative data about our workshops and to show how interest and attendance have increased through the years. We talk about some innovations we have introduced to improve quality (e.g., the PhD school “from young researchers to young researchers” and the pitch talk session). We then share our personal opinion and, last but not least, we invite young researchers to join in the preparation of the next AIROYoung Workshops.

In system optimal traffic assignment of traffic flows with user constraints the total travel time is minimized on a set of paths with bounded length ensuring a certain level of fairness for users. Minimizing the total travel time may lead to experience large travel times on some arcs. On the other hand, when minimizing the maximum arc travel time, the total travel time cannot be controlled. The increase of arc travel time with respect to arc free-flow travel time is related to the arc congestion that is one of the main issues in road networks. In this paper we propose a new model that is a compromise between minimizing the average arc congestion and the worst arc congestion on the road network. The model is a linear program that minimizes the average arc congestion over a given percentage of the most congested arcs. A heuristic algorithm aimed at reducing the number of paths that are considered for the model is also proposed. A computational study is performed that shows the flexibility of the model and the quality of the heuristic.

The benefits in reducing traffic congestion of system optimum with respect to user equilibrium traffic assignments are well-known. Recently a linear programming based approach was proposed that aims at achieving a compromise between the system perspective, namely eliminating congestion, and the user perspective, that is minimizing individual travel times. The approach, called proactive route guidance, assigns to users paths that increase the travel times by at most a given percentage, called Maximum allowed travel inconvenience. The approach requires the enumeration of all feasible paths that may be memory and time consuming, especially when large networks and/or high values of the Maximum allowed travel inconvenience are considered. In this paper a heuristic is presented to generate a subset of all feasible paths that is based on the iterative search of improving paths. Computational experiments show that the number of paths generated by the heuristic is smaller with respect to the complete set by one or two orders of magnitude on small instances and by higher orders of magnitude when the size of the instances increases. On instances with 150 nodes, where the complete enumeration takes an acceptable computational time, the results show that the quality of the heuristic solutions is very close to that of the optimal ones.

We report on the optical and photo-physical properties of a fluorinated poly(p-phenylenevinylene) derivative, namely poly(2-methoxy-5-[(2-ethylhexyl)oxy]-1,4-phenylenedifluorovinylene) (MEH-PPDFV) and we compare them with those of the well-known non fluorinated reference system, poly(2-methoxy-5-[(2-ethylhexyl)oxy]-1,4-phenylenevinylene) (MEH-PPV) synthesized with the same procedure. Remarkable blue-shifts of absorption and emission spectra of MEH-PPDFV with respect to MEH-PPV are observed, due to the larger distortion from planarity of the fluorinated species. In addition, the blue-shift for optical transitions in absorption spectra is more pronounced than in emission ones, since the molecule conformation in the excited states is more planar than in the ground one. Microsecond photo-induced absorption spectra of MEH-PPDFV reveal three bands possessing spectral properties and/or kinetics different from those observed for MEH-PPV. The assignment of these transitions is provided in terms of free and trapped polarons as well of triplet excitons. Free-polarons have an intrinsic decay constant of 3 μs, while the trapping dynamics has a longer kinetics of 40 μs. The triplet exciton, instead, shows a monoexponetial decay behavior of constant about 10 μs.

We propose a proactive route guidance approach that integrates a system perspective: minimizing congestion, and a user perspective: minimizing travel inconvenience. The approach assigns paths to users so as to minimize congestion while not increasing their travel inconvenience too much. A maximum level of travel inconvenience is ensured and a certain level of fairness is maintained by limiting the set of considered paths for each Origin-Destination pair to those whose relative difference with respect to the shortest (least-duration) path, called travel inconvenience, is below a given threshold. The approach hierarchically minimizes the maximum arc utilization and the weighted average experienced travel inconvenience. Minimizing the maximum arc utilization in the network, i.e., the ratio of the number of vehicles entering an arc per time unit and the maximum number of vehicles per time unit at which vehicles can enter the arc and experience no slowdown due to congestion effects, is a system-oriented objective, while minimizing the weighted average experienced travel inconvenience, i.e., the average travel inconvenience over all eligible paths weighted by the number of vehicles per time unit that traverse the path, is a user-oriented objective. By design, to ensure computational efficiency, the approach only solves linear programming models. In a computational study using benchmark instances reflecting a road infrastructure encountered in many cities, we analyze, for different levels of maximum travel inconvenience and, the minimum maximum arc utilization and the weighted average experienced travel inconvenience. We find that accepting relatively small levels of maximum travel inconvenience can result in a significant reduction, or avoiding, of congestion.

Ring the changes: Experimental Raman spectra of fluorinated and non-fluorinated polyphenylenevinylenes are assigned according to quantum chemical calculations for oligomer model systems [picture: see text]. Characteristic differences in the spectra can be traced back to strong inter-ring distortion of the fluorinated compounds.The Raman spectrum of poly{2-methoxy-5-[(2-ethylhexyl)oxy]-1,4-phenylenedifluorovinylene} (MEH-PPDFV) is reported and compared with that of a well-known non-fluorinated reference polymer, namely poly{2-methoxy-5-[(2-ethylhexyl)oxy]-1,4-phenylenevinylene} (MEH-PPV). The Raman spectra of both polymers are assigned on the basis of density functional theory calculations of the corresponding oligomers. The main differences between vinylene fluorinated and non-fluorinated structures deal with the intensity, frequency shift and broadening of C--C vinylene stretching. Additional differences concern the relative intensities of C-C phenylene and vinylene stretching as well as the deformation modes in the range 1250-1350 cm(-1). It is shown that these effects are due to the larger distortion from planarity of the fluorinated polymer, compared with the non-fluorinated counterpart, induced by repulsive interactions between the fluorine atoms on the vinylene units and the oxygen atoms of the alkoxy groups on the aromatic rings.

This article presents analysis of air service levels and competition dynamics in the transatlantic market before and after the EU-US Open Skies Agreement (OSA) signed in 2008. By comparing direct and connecting flights in a typical off-peak week, we investigate whether the EU-US OSA has led to more choices for transatlantic travelers. We examine the impact of the EU-US OSA on competition between carriers, alliances, and hub airports. The results show that the number of direct transatlantic connections and served airport pairs decreased and only indirect competition increased.

Mariasole Banno and Valentina Morandi analyse the Interactions between innovation and internationalisation policy at a regional level, and suggest that policymakers need to be more co-ordinated.

Polystyrene artificial opals having both different microsphere diameters and gold nanoparticles (AuNP) doping levels have been prepared and their spectroscopic characterization has been performed. Reflectance spectra of doped opals show a red shift of the photonic band gap and a reduction of its width and intensity upon increasing AuNP doping level, but they do not show any direct evidence of AuNP plasmon resonance. Transmittance spectra of the same samples recorded on the same spot area show, instead, a doping level dependent line shape. For the highest doping level a complicated sigmoidal line shape due to the overlap of broad AuNP absorption and photonic crystal stop band is observed. This unusual effect is accounted for by considering the localization of standing electromagnetic waves within both the microspheres and the interstices where the AuNP are embedded.

Polystyrene artificial opals with few gold nanoparticles (AuNp) embedded in the interstices (doping) are grown by using the meniscus technique starting from a mixed suspension of microspheres and AuNp. Samples having different sphere diameters and nanoparticle loads have been prepared. Their reflectance spectra clearly show a dramatic bathochromic shift of the photonic stop band (up to 1400 cm–1) and a reduction of its full width half maximum, due to an increase of the effective refractive index of about 8 % with respect to bare opals, which is accounted for by analytical theoretical models. Reflectance spectra do not show any direct evidence of AuNp absorption even at the higher AuNp doping level. Nanosecond transient absorption measurements on these systems indicate that a variation of transmission (optical switching) of about 150 % is observed for AuNp doped opals upon photoexcitation with 9 ns laser pulses at 532 nm. No switching is instead observed for bare opals.

Polystyrene artificial opals are directly grown with embedded gold nanoparticles (NpAu) in their interstices. Reflectance spectra of samples having different sphere diameters and nanoparticles load clearly show a red shift of the photonic band gap as well as a reduction of its width without showing direct evidence of NpAu absorption. The case of transmission spectra is instead more complicated: here, overlapped to a broad NpAu absorption, a structure having unusual lineshape is detected. The infiltration of opal with NpAu removes the polarization dependence of the photonic band structure observed in bare opals. The lineshape of the absorption spectra suggest a spatial localization of the electromagnetic field in the volume where NpAu are confined thus enhancing its local intensity. This effect seems to be effective to stimulate optical nonlinearities of NpAu. Nanosecond transient absorption measurements on NpAu infiltrated opals indicate that a variation of transmission of about 10% is observed. Since this effect takes place within the pump pulse and since NpAu photoluminescence has been subtracted to the signal, we attribute it to an optical switching process.